i INVESTIGATIONS OF FACTORS AFFECTING PENDULUM TEST VALUE ON ASPHALTIC CONCRETE SURFACES SUDESH NAIR A/L BASKARA A project report submitted in partial fulfillment of the requirements for the award of the degree of Master ofCivil Engineering (Transportation and Highway) Faculty of Civil Engineering Universiti Teknologi Malaysia JUNE 2009 iii Dedicated To Highway Engineering Relevant Parties… iv ACKNOWLEDGEMENT Firstly, I am thankful to God for completing this report successfully. I would also like to thank my supervisors, Dr Haryati Yaacob and Associate Professor Dr Mohd Rosli Hainin for their guidance, advice and continuous support throughout the course of this research. Their kindness and encouragement made me always active and confident. I would also like to thank highway technicians En Suhaimi, En Rahman, En Azman and En Ahmad for their guidance on handling and operating the laboratory equipments. Thank to my colleague, Dorina Anak Astana for her assistance in helping me on my laboratory works. I also would like to express my gratitude to my parents for their encouragement and support. Their views and tips are useful indeed. Finally, I hope that this report will be beneficial in the future. v ABSTRACT Skidding is one of the major contributions to road accidents during wet weather condition. Therefore, a study is conducted to investigate the factors affecting Pendulum Test Value on Asphaltic Concrete surfaces. The main objective of this study is to determine the mix type and the crossfall percentage that best resist skid during wet weather condition. Three different types of dense graded mixes were used in this study which are AC10, AC14 and AC20. Those three mixes are tested using Sand Patch Test (SPT) and are then subjected to various rainfall conditions and crossfall percentages using Rainfall Simulator. The rainfall conditions are categorized as low rainfall, medium rainfall and high rainfall while the crossfalls were increased 2% from 0% to 10% crossfalls. During the event of rainfall on each mix surfaces, a Portable Skid Resistance Tester is used on the mix to obtain the Pendulum Test Value (PTV) at different crossfalls. Results are analyzed using analysis of variance (ANOVA) to justify the objectives. Results from PTV shows that 4% to 10% crossfall and AC20 is the best crossfall and surface type in resisting skid. vi ABSTRAK Gelinciran merupakan salah satu penyumbang utama kepada kemalangan jalan raya terutamanya ketika hujan. Oleh itu, kajian ini dijalankan untuk menyelidik faktorfaktor yang mempengaruhi rintangan gelinciran di atas permukaan konkrit berasfal. Objektif utama kajian ini ialah untuk menentukan jenis campuran dan peratus sendengan jalan yang terbaik untuk menghalang dari berlakunya gelinciran ketika keadaaan hujan. Tiga jenis campuran konkrit berasfal digunakan dalam kajian ini iaitu AC10, AC14 dan AC20. Ketiga-tiga campuran tersebut diuji menggunakan ujian tampalan pasir dan kemudiannya dikenakan keadaan hujan dan peratus sendengan jalan yang berlainan dengan menggunakan alat simulasi hujan. Keadaan hujan yang dikenakan adalah hujan renyai, hujan sederhana dan hujan lebat manakala sendengan jalan ialah dari 0% hingga 10% dengan kenaikan 2%. Ketika hujan dikenakan ke atas permukaan campuran konkrit berasfal. Alat rintangan gelinciran diletakkan di atas campuran konkrit berasfal untuk mendapatkan bacaan rintangan gelinciran pada sendengan jalan berlainan. Keputusan akan dianalisa menggunakan Analysis of Variance (ANOVA) untuk mengesahkan objektif tersebut. Keputusan nilai rintangan gelinciran menunjukkan bahawa sendengan jalan 4% hingga 10% dan AC20 ialah sendengan jalan dan jenis permukaan yang terbaik untuk menghalang gelinciran. vii TABLE OF CONTENTS CHAPTER 1 2 TITLE PAGE DECLARATION ii DEDICATION iii ACKNOWLEDGEMENTS iv ABSTRACT v ABSTRAK vi TABLE OF CONTENTS vii LIST OF TABLES xi LIST OF FIGURES xiii LIST OF SYMBOLS AND ABBREVIATIONS xv LIST OF APPENDICES xvi INTRODUCTION 1 1.1 General 1 1.2 Problem Statement 2 1.3 Objective of Study 4 1.4 Scope of Study 4 1.5 Importance of study 5 LITERATURE REVIEW 6 2.1 6 Introduction viii 2.2 Rainfall Intensity 6 2.3 Surface Runoff 8 2.4 Hot Mix Asphalt Types 9 2.4.1 Dense-Graded Mixes 10 2.4.2 Asphalt Characteristics 11 Aggregate 11 2.5.1 Aggregate Physical Properties 12 2.5.2 Maximum Aggregate Size 13 2.5.3 Gradation 13 2.5.3.1 Gradation Design for Dense Graded Mix 15 2.5.4 Other Properties 16 2.6 Crossfall 16 2.7 Skidding 18 2.8 Pavement Surface Characteristics 20 2.9 The Skidding Factors 22 2.9.1 The Texture of The Road Surface 22 2.9.2 The Aggregate at the Road Surface 24 2.9.3 Condition of the road surface 24 2.9.4 Weather condition 25 2.10 Water Film Thickness 26 2.11 Rainfall Simulator 30 2.12 Portable Skid Tester 31 2.5 3 METHODOLOGY 32 3.1 Introduction 32 3.2 Determination of Rainfall Intensity and Flowrate 35 3.3 Material Selection 36 3.4 Sieve Analysis 36 3.4.1 Dry Sieve 37 3.5 Grade Selection 38 3.6 Blending of Stockpile Specimen 38 ix 4 3.7 Optimum Bitumen Content 39 3.8 Mixing of Specimen 39 3.9 Compaction 40 3.10 Pavement Mix 41 3.11 Rainfall Simulator Test 41 3.12 Sand Patch Method 42 3.13 Pendulum Test Value 44 3.14 Runoff Flowrate and Water Film Thickness 46 3.15 Core Specific Gravity and Degree of Compaction 46 3.16 Analysis of Variance (ANOVA) 48 DATA AND ANALYSIS 49 4.1 Introduction 49 4.2 Sieve Analysis 50 4.3 Wash Sieve 52 4.4 Penetration and Softening Point Test 52 4.5 Optimum Bitumen Content 52 4.6 Determination of Mass for Rainfall Simulator Mould 53 4.7 Determination of Rainfall Using MASMA 53 4.8 Determination of Pavement Crossfall 54 4.9 Polished Stone Value 54 4.10 Sand Patch Test 55 4.11 Pendulum Test Value 57 4.11.1 The Effect of Rainfall Intensity on PTV 59 4.11.2 The Effect of Crossfall on PTV 63 4.11.3 The Effect of Surface Texture on PTV 65 4.12 Runoff and Water Film Thickness Data 70 4.13 Degree of Compaction and Specific Gravity 71 4.14 Analysis of Variance (ANOVA) Results 73 x 5 CONCLUSION AND RECOMMENDATIONS 77 5.1 Conclusion 77 5.2 Recommendation 78 REFERENCES 80 APPENDICES 84 xi LIST OF TABLES NO TITLE PAGE 2.1 Annual Recurrence Interval For Type Of Development 7 2.2 Coefficient of Runoff (ASCE, 1960) 9 2.3 Gradation Limit For Asphaltic Concrete (JKR/SPJ/rev2005) 15 2.4 Normal Pavement Cross Slopes (AASHTO, 1990) 18 2.5 Suggested Minimum Values Of Skid Resistance Numbers 20 2.6 Correlation of Macrotexture and British Pendulum Number 22 2.7 Influence of Texture on Variables 23 3.1 Gradation Limit For Asphaltic Concrete (JKR, 2005) 38 4.1 OBC, Gmb and TMD for 100 gyrations at 4% air void 53 4.2 Polishing Stone Value Results 55 4.3 Sand Patch Test Results for AC10 56 4.4 Sand Patch Test Results for AC14 56 4.5 Sand Patch Test Results for AC20 57 4.6 Pendulum Test Value for AC10, AC14 and AC20 58 4.7 Water Film Thickness and The Runoff of AC10, AC14 and AC20 71 4.8 The Specific Gravity and the Degree of Compaction of AC10, AC14,AC20 72 4.9 Permeability Test Result of AC20 73 4.10 ANOVA of Rainfall Intensity on Crossfall 74 xii 4.11 ANOVA of Rainfall Intensity on Surface Type 74 4.12 ANOVA of Crossfall on Rainfall Intensity 75 4.13 ANOVA of Crossfall on Surface Type 75 4.14 ANOVA of Surface Type on Rainfall Intensity 76 4.15 ANOVA of Surface Type on Crossfall 76 xiii LIST OF FIGURES FIGURE TITLE PAGE 1.1 Statistics Road Accidents in Malaysia Year 1974 to Year 2005 3 2.1 Dense Grade Mix 10 2.2 Asphaltic Concrete Surface Texture (Rebecca, 2004) 10 2.3 Separation of aggregates into different sizes 12 2.4 Typical two-lane highway with linear cross slopes 17 2.5 Microtexture and Macrotexture 21 2.6 Schematic of a Rolling Tyre on a Wet Road Surface 25 2.7 Water Film Thickness, Mean Texture Depth, and Total Flow 26 2.8 Water Film Depth vs Surface Texture Depth 27 2.9 Water Film Depth vs Slope 28 2.10 Water Film Depth vs Rainfall Intensity 28 2.11 Microtexture vs Film Thickness 29 2.12. Macrotexture vs Film Thickness 30 2.13 Rainfall Simulator 31 2.14 Portable Skid Resistance Tester 31 3.1 Flow of Laboratory Testing 33 3.2 MASMA IDF Curve for Kuala Lumpur (MASMA) 35 3.3 Hot Mixing of Aggregate and Bitumen 40 3.4 Steel Roller Compactor 40 xiv 3.5: Pavement Mix 41 3.6 Sand Patch Test on Pavement Mixes 44 3.7 Cored Samples for Different Mixes 47 4.1 Gradation for AC10 (Elizabeth, 2006) 50 4.2 Gradation for AC14 (Elizabeth, 2006) 51 4.3 Gradation for AC20 (Elizabeth, 2006) 51 4.4 Pendulum Test Value vs Intensity at 0% crossfall 60 4.5 Pendulum Test Value vs Intensity at 2% crossfall 60 4.6 Pendulum Test Value vs Intensity at 4% crossfall 61 4.7 Pendulum Test Value vs Intensity at 6% crossfall 61 4.8 Pendulum Test Value vs Intensity at 8% crossfall 62 4.9 Pendulum Test Value vs Intensity at 10% crossfall 62 4.10 Pendulum Test Value vs Crossfall for AC10 64 4.11 Pendulum Test Value vs Crossfall for AC14 64 4.12 Pendulum Test Value vs Crossfall for AC20 65 4.13 Pendulum Test Value vs Texture Depth at 0% Crossfall 67 4.14 Pendulum Test Value vs Texture Depth at 2% Crossfall 67 4.15 Pendulum Test Value vs Texture Depth at 4% Crossfall 68 4.16 Pendulum Test Value vs Texture Depth at 6% Crossfall 68 4.17 Pendulum Test Value vs Texture Depth at 8% Crossfall 69 4.18 Pendulum Test Value vs Texture Depth at 10% Crossfall 69 xv LIST OF SYMBOLS AND ABBREVIATIONS AC Asphaltic Concrete NAPA National Asphalt Pavement Association JKR Jabatan Kerja Raya ATJ Arahan Teknik Jalan ASTM American Society for Testing and Materials AASTHO American Association of State Highway and Transportation Officials UTM Universiti Teknologi Malaysia OBC Optimum Bitumen Content MRP Malaysia Rock Product SPT Sand Patch Test BPT British Pendulum Tester BPN British Pendulum Number PTV Pendulum Test Value SRV Skid Resistance Value WFT Water Film Thickness ANOVA Analysis of Variance xvi LIST OF APPENDICES APPENDIX TITLE PAGE 1 Sieve Analysis Gradation 84 2 Wash Sieve 85 3 Penetration and Softening Test 86 4 Mass for Rainfall Simulator Mould 87 5 Rainfall Design and Rational Method 91 6 Pavement Crossfall 94 7 Sand Density and Volume Calculation 95 8 Pendulum Test Value 96 9 Analysis Of Variance 103 10 Pictures of Laboratory Testing 127 1 CHAPTER I INTRODUCTION 1.2 General Skidding is one of the most common contributors to accidents. Skidding is more effective to happen during wet pavement condition. Apart from that, skidding also can happen due to the insufficient of pavement crossfall and pavement surface characteristics. Skidding can be avoided if there is a good friction between tyre and pavement. Pavement surface characteristics are important for both the safety and comfort of drivers. Pavement surfaces should provide adequate friction and maintain a good level of ride quality and to ensure the satisfaction of the driving. Both the macrotexture and microtexture plays an important role in the friction characteristics of pavement surfaces. 2 The frequency of rainfall based on rainfall intensity also contributes in pavement friction. The frequency of rainfall develops water film on pavement which exists between the tyre-pavement contact. This could eventually creates hydroplaning thus contributes to skidding. Crossfall is another important element in providing good friction between tyre and pavement. Crossfall is essential in highway construction since it functions to reduce water on pavement during rainy weather. 1.2 Problem Statement Malaysia is currently having one of the best road systems in Asia. Eventhough Malaysia has the best road system; the accident rate is Malaysia increased at an average rate 9.7% yearly (Royal Malaysian Police, 2005). Figure 1.1 below shows that road accidents had increased from 24,581 cases in 1974 to 328,264 cases in 2005. 3 Figure 1.1: Statistics Road Accidents in Malaysia Year 1974 to Year 2005 (Royal Malaysian Police, 2005). Accidents is high in Malaysia due to many factors such as the driver carelessness, vehicle speed, braking distance, insufficient head distance and skidding especially on wet condition. One major factor contributes to road accident is skidding as there is connection between vehicle tyre and pavement. The worst skidding ever happen is during wet pavement condition during rainy day. Besides that, a research shows that skidding contributes to 25% of wet road accidents in United Kingdom (Kennedy et al., 1990). As Malaysia utilizes more Asphaltic Concrete pavements and Malaysia is located in Khatulistiwa climate region, the skidding rate on wet pavement condition has to be determined. Therefore a lab test will be carried out to investigate the factors affecting the Pendulum Test Value of Asphaltic Concrete surfaces. 4 1.3 Objective of Study The objectives of this study are: · to investigate the effect Pendulum Test Value on various rainfall intensities, various crossfalls and on different Asphaltic Concrete surfaces during rainfall. · to recommend the crossfall and pavement type that best resist skid during wet pavement condition. 1.4 Scope of Study This study is carried out at Makmal Jalanraya, Universiti Teknologi Malaysia (UTM). Rainfall Simulator is used to simulate various type of rainfall on pavement. Three asphaltic concrete pavement type being used in this study which are AC10, AC14 and AC20. Crushed aggregates from a quarry in Ulu Choh and bitumen of 80/100 Pen is used for the design mix. Sand Patch Test is carried out on every mix samples. Besides that, the Pendulum Test Value is determined by using Portable Skid Tester. Data from Manual Saliran Mesra Alam (MASMA, 2000) is used to calculate rainfall intensities and Jabatan Kerja Raya (JKR, 2005) specification is used in the mix design for this study. 5 1.5 Importance of study The importance of this study is mainly to propose the best crossfall and the best asphaltic concrete mix type to resist skid by rainfall simulation before constructing road on a particular area. Other than that, by conducting this study, the relationship of crossfall, rainfall intensity and pavement texture can be observed and determined. Besides that, this study can be highlighted as a proposal to JKR and local authorities. Overall, this study is aimed to give a new idea and concept towards the road development in Malaysia. 6 CHAPTER II LITERATURE REVIEW 2.2 Introduction There are four major aspect need to be taken into consideration before conducting the study. The four main aspects are the rainfall intensity, the crossfall, the surface type and the water film thickness. Those four aspects are interrelated between each other in evaluating skidding by PTV during rainy weather. In order to obtain a basic understanding on all those aspects, reviews on literature is essential. 2.2 Rainfall Intensity The design rainfall intensity is based on the Average Recurrence Interval (ARI) and the time of concentration. According to Manual Saliran Mesra Alam (MASMA) 7 guideline, the polynomial expression as shown in Equation 2.1 is used to calculate rainfall intensity of less than 30min while the Intensity Duration Frequency (IDF) curve is used to calculate tainfall intensity of more than 30min. Based on MASMA (2000), the annual Recurrence Interval for type of development is shown in Table 2.1. ln(It) = a + b (ln t) + c (ln t)2 + d (ln t)3 (Equation 2.1) Table 2.1: Annual Recurrence Interval For Type Of Development (MASMA, 2000) Average Recurrence Interval Type of Development Open Spaces, Parks and Agriculture Land in urban areas Quantity Minor System Major System 1 Up to 100 Quality Residential · Low Density 2 Up to 100 · Medium Density 5 Up to 100 · High Density 10 Up to 100 5 Up to 100 10 Up to 100 Commercial, Business and Industrial – other than CBD Commercial, Business, Industrial in Central Business District (CBD) areas of Large Cities 3 month ARI 8 2.3 Surface Runoff Surface Runoff is determined through the amount of excessive precipitation. This includes variety of ways by which water moves across the land. The surface runoff on pavements usually removes all water that present on pavement to drainage system. According to MASMA, the Rational Method is the common method used to calculate peak runoff from rainfall intensity. This method is essential to estimate the peak flowrate at an area of less than 80 hectares. The surface runoff is calculated based on Rational Method formula in Equation 2.2. The coefficient of runoff obtained from American Society of Civil Engineering (ASCE, 1960) is shown in Table 2.2. Q= CIA (Equation 2.2) 360 Where Q = peak flow (m3/s) C = coefficient of runoff I = average rainfall intensity(mm/hr) A = drainage area (ha) 9 Table 2.2: Coefficient of Runoff (ASCE, 1960) Type of Drainage Area Runoff Coefficient Railroad yard areas 0.20 – 0.40 Unimproved areas 0.10 – 0.30 Lawns · Sandy soil, flat, 2% 0.05 – 0.10 · Sandy soil, average, 2-7% 0.10 – 0.15 · Sandy soil, steep, 7% 0.15 – 0.20 · Heavy soil, flat, 2% 0.13 – 0.17 · Heavy sil, average, 2-7% 0.18 – 0.22 · Heavy soil, steep, 7% 0.25 – 0.35 · Asphaltic 0.70 – 0.95 · Concrete 0.80 – 0.95 · Bricks 0.70 – 0.85 Streets Drives and walks 0.75 – 0.85 Roofs 0.75 – 0.95 2.4 Hot Mix Asphalt Types Hot Mix Asphalt (HMA) is the most common flexible pavement and it is distinguished by its design and production methods which include dense-graded mixes as well as stone matrix asphalt (SMA) and open-graded mixes. HMA is known as hot mix, asphalt concrete (AC), asphalt or bitumen. HMA can be produced through various types and grades. It can be determine from the total relative of: i. coarse aggregate (retained sieve 2.36mm) ii. fine aggregate (passed sieve 2.36mm) iii. filler (passed sieve 75 µm) 10 2.4.1 Dense-Graded Mixes A dense-graded mix is a well-graded HMA and it is relatively impermeable. They can be classified as fine-graded or coarse-graded. Fine-graded mixes have more fine and sand sized particles compared to coarse-graded mixes. This mix can suit all pavement layers and all traffic conditions. Dense graded mix involves a combination of well graded aggregate and asphalt binder. Figure 2.1 and Figure 2.2 shows the mix structure and the texture respectively. Figure 2.1: Dense Grade Mix Figure 2.2: Asphaltic Concrete Surface Texture (Rebecca, 2004) 11 2.4.2 Asphalt Characteristics Asphalt is a strong cementations material, sticking agent, long lasting, and high in water repellent. Besides that, it becomes plastic when mixed with aggregate. Asphalt has colloidal feature which is solid at normal temperature and becomes liquid on higher temperature level. 2.5 Aggregate Aggregate is a collective term for mineral materials such as sand, gravel and crushed stone which is used with a binding medium such as water, bitumen, Portland cement and lime to form compound materials such as asphalt concrete and Portland cement concrete. (Roberts et.al., 1996) The constituent of aggregate in HMA generally covers up to 92 to 96 percent. Aggregates can be natural or manufactured. Natural aggregates are extracted from larger rock formations through quarry. Manufactured aggregate is obtained from the byproduct of manufacturing industries such as slag (byproduct of the metallurgical processing – typically produced from processing steel, tin and copper) (Roberts et.al.,1996) 12 2.5.1 Aggregate Physical Properties The pavement industry typically relies on physical properties for performance characterization. (Roberts et.al.,1996) Commonly measured physical aggregate properties are: · Gradation and size · Toughness and abrasion resistance · Durability and soundness · Particle shape and surface texture · Specific gravity Figure 2.3: Separation of aggregates into different sizes 13 2.5.2 Maximum Aggregate Size Maximum aggregate size can affect HMA and base courses in several ways. Excessive small maximum sizes may form instability in HMA mix while excessive large maximum sizes contribute to poor workability and segregation. (Roberts et.al.,1996) Definition of the maximum aggregate size in one of two ways: · Maximum size. The smallest sieve through which 100 percent of the aggregate sample particles pass · Nominal maximum size. The largest sieve that retains some of the aggregate particles but generally not more than 10 percent by weight It is important to specify whether "maximum size" or "nominal maximum size" is being referenced. 2.5.3 Gradation Gradation in HMA helps to determine important property including stiffness, stability, durability, permeability, workability, fatigue resistance, frictional resistance and resistance to moisture damage. Therefore, gradation must be a primary concern in HMA mix design. Gradation is usually measured using a sieve analysis to determine the 14 type of gradation such as dense graded, gap graded, open graded and uniformly graded. (Roberts et.al.,1996) · Fine aggregate Defined by AASHTO M 147 as natural or crushed sand passing the No. 10 sieve and mineral particles passing the No. 200 sieve. · Coarse aggregate. Defined by AASHTO M 147 as hard, durable particles or fragments of stone, gravel or slag retained on the No. 10 sieve. Usually coarse aggregate has a toughness and abrasion resistance requirement. · Mineral filler. Defined by the Asphalt Institute as a finely divided mineral product at least 65 percent of which will pass through a No. 200 sieve. Pulverized limestone is the most commonly manufactured mineral filler, although other stone dust, silica, hydrated lime, Portland cement and certain natural deposits of finely divided mineral matter are also used. 15 2.5.3.1 Gradation Design for Dense Graded Mix (Asphaltic Concrete) The gradation of asphaltic concrete mixes is shown in Table 2.3. Table 2.3: Gradation Limit For Asphaltic Concrete (JKR/SPJ/rev2005) Mix Type Wearing Course Wearing Course Wearing Course Mix Designation AC 10 AC 14 AC 20 BS Sieve Size, mm Percentage Passing ( by weight) 100 28.0 20.0 100 76-100 14.0 100 90-100 64-89 10.0 90-100 76-86 56-81 5.0 58-72 50-62 46-71 3.35 48-64 40-54 32-58 1.18 22-40 18-34 20-42 0.425 12-26 12-24 12-28 0.150 6-14 6-14 6-16 0.075 4-8 4-8 4-8 Note: AC20 Gradation obtained from (JKR/SPJ/1988) 16 2.5.4 Other Properties According to Roberts et.al.(1996), other important aggregate physical properties are: i. Toughness and abrasion resistance. Aggregates should be hard and tough enough to resist crushing, degradation and disintegration from activities such as manufacturing, stockpiling, placing and compaction. ii. Durability and soundness. Aggregates must be resistant to breakdown and disintegration from weathering (wetting/drying) or else they may break apart and cause premature pavement distress. iii. Particle shape and surface texture. Particle shape and surface texture are important for proper compaction, load resistance and workability. Generally, cubic angular-shaped particles with a rough surface texture are best. iv. Specific gravity. Aggregate specific gravity is useful in making weight-volume conversions and in calculating the void content in compacted HMA 2.6 Crossfall The American Association of State Highway and Transportation Officials (AASHTO, 1990) recommends a cross slope of 1.5% to 2% for high type pavement, 1.5% to 3% for intermediate type pavement and 2% - 6% for low type pavements. However, crossfalls recommended by Arahan Teknik Jalan (8/86) are 2.5% for high type pavement, 2.5% – 3.5% for intermediate type pavement, 2.5% - 6.0% for low type 17 pavements. The cross slopes depends generally on the type of pavement used and the rainfall intensity at the area. AASHTO states that the high type pavement is classified as the wearing surface that can withstand high-volume, heavy vehicles and high speed for a long period of time. The intermediate type pavement is similar to the high type pavement except they are constructed with less strict standard and rules. The low type pavement utilizes low cost roads such as surface treated earth and stabilized material. Figure 2.4 illustrates the typical two lane highway with linear cross slopes. (Garrabrant. R, 2004). Figure 2.4: Typical two-lane highway with linear cross slopes. (Garrabrant. R, 2004) Table 2.4 indicates an acceptable range of cross slopes. The cross slopes ranges from steep cross slopes for drainage and relatively flat cross slopes for driver comfort and safety. Cross slopes of 2 percent have little effect on driver effort in steering but in areas of high rainfall intensity, a steeper cross slope can be used to facilitate drainage. (AASHTO, 1990) 18 Table 2.4: Normal Pavement Cross Slopes (AASHTO, 1990) Surface Type Range in Rate Surface Slope High-type surface · 2 lanes 0.015 – 0.020 · 3 or more lanes, each direction 0.015 – 0.040 Intermediate surface 0.015 – 0.03 Low-type surface 0.020 – 0.060 Shoulders · Bituminous or concrete · With curbs 0.020 – 0.060 > 0.040 Equation 2.3 shows that the slope formula which is the percentage of differences in height to differences in horizontal. (Brouwer et.al., 1985). Slope in % = Height differences . (Equation 2.3) Horizontal differences 2.7 Skidding Skid occurs when the available friction between the pavement surface and the tire is insufficient to respond to the maneuver a driver is attempting to make. This happens when the vehicle is maneuvered by the exerted forces at that stationary area where the friction between the tire and the road surface opposes to the maneuvering force. A dry road surface condition produces high road and tyre friction for normal 19 driving maneuvers while the wet road surfaces decreases the friction effect significantly causing skidding accidents. (Kokkalis et.al. 2002) Skid resistance is the force developed when a tire that is prevented from rotating slides along the pavement surface. Skid resistance controls contact between the tire rubber and the pavement surface. Skid resistance is an important pavement evaluation parameter because inadequate skid resistance will leads to higher skid related accidents besides road user often rely on safe pavement. Skid resistance changes over time. Skid resistance is also typically lower in wet condition and higher in dry condition. Skid resistance is generally quantified using friction factor, skid number or British Pendulum Number. (Nor Zolhanita, 2007). Table 2.5 shows the minimum Skid Resistance Value measured with British Pendulum Tester. (British Pendulum Manual, 2000) 20 Table 2.5: Suggested Min Skid Resistance Value (British Pendulum Manual, 2000) Minimum Category Type of site SRV (Surface wet) A Difficult sites such as: i. Roundabouts ii. Bends with radius less than 150m or unrestricted 65 iii. Gradients, 1 in 20 or steepr of length greater than 100m iv. Approaches to traffic lights on unrestricted roads B Motorways, trunk and class 1 roads and heavily trafficked roads in urban area C 2.8 All other sites 55 45 Pavement Surface Characteristics Pavement surface characteristics are important for both safety and comfort of drivers. Pavement surfaces should provide adequate friction and maintain a good level of ride quality. The combination of good friction and low levels of roughness are important in the design of a pavement wearing surface. (Flintsch et. al., 2001) The surface texture of a pavement wearing surface is one of the primary contributors to tire-pavement friction. The surface texture can be divided into two which are macrotexture and microtexture as shown in Figure 2.5. Pavement texture can generates energy losses in the tyre when it is skidding. In this process, some of the energy used to deform the tyre tread during sliding on the texture is absorbed back by the tyre to returns to its original shape. In wet conditions, as vehicle speeds increase, the 21 possibility of skidding is high. The extent to which this occurs depends upon the texture depth. (Flintsch et. al., 2001) Good macrotexture pavement allows for the rapid drainage of water from the pavement that improves the contact between the tire and the pavement surface. The macrotexture of a pavement surface results from the large aggregate particles in the mixture. Common macrotexture measurement methods include the sand patch method, the outflow meter, and the circular texture meter. (Flintsch et. al., 2001) Microtexture provides direct tire pavement contact and contributes to tyre pavement friction and it is the major contributing factor to skidding resistance at low speeds. Microtexture is gradually polished away by heavy traffic and gradually decreases the skidding resistance. (Flintsch et. al., 2001) Figure 2.5: Microtexture and Macrotexture (Flintsch et. al., 2001) 22 2.9 The Skidding Factors 2.9.1 The Texture of The Road Surface There are two texture type of road surface influencing skidding which are macrotexture and microtexture. Macrotexture is required to the eliminate water from the contact area between the tyre and the road surface especially at higher vehicle speeds. The macro texture is determined by the size of the aggregate particles at the road surface. (Molenaar et al, 2004) The micro texture is determined by the roughness and angularity of the surface of the aggregate particles. The micro texture ensures high contact pressures between the aggregate and the tyre. (Molenaar et al, 2004) A study by Peter Cairney et.al. (2006) on four sites along Princes Highway West proves that a bigger macrotexture depth creates a bigger British Pendulum Number (BPN) while a smaller mactotexture depth generates smaller British Pendulum Number. The surface characteristics of the study shown in Table 2.6. Table 2.6: Correlation of Macrotexture and BPN (Peter Cairney et al, 2006) Site Macrotexture British Pendulum Number Site 1 > 0.7mm 68 Site 2 < 0.4mm 64 Site 3 < 0.4mm 50 Site 4 > 0.7mm 74 23 Table 2.7 shows a study by Sandberg (1997) indicating the influence of macrotexture and microtexture on different variables. The influence of microtexture on friction is high and the influence of marotexture on water runoff is high. Table 2.7: Influence of Texture on Variables (Sandberg, 1997) Effect on Vehicle, Driver or Road Surface Characteristics Environment of Importance Friction Macrotexture High Megatexture Moderate Microtexture Very High Rolling Resistance/Fuel Macrotexture High Consumption/Air Pollution Megatexture Very High Uneveness High Macrotexture Moderate Microtexture Very High Macrotexture Very High Megatexture Very High Water Runoff Macrotexture High Splash and Spray Macrotexture High Light Reflector Macrotexture High Microtexture Little Macrotexture High Megatexture Very High Uneveness High Tire Wear Exterior Noise Interior Noise Magnitude of the Influence 24 2.9.2 The Aggregate at the Road Surface The aggregate at the road surfaces are relevant with respect to the skidding resistance: · the shape and the size · the resistance against polishing · the resistance against crushing · the bond with the binding agent (bitumen or cement). In general crushed aggregates have sharp and rough surfaces that favor the texture and the skidding resistance. However, polishing of the aggregates occurs under the repeated traffic loadings. The rate of polishing is dependent on the type of aggregate and the traffic intensity. The skidding resistance is also negatively influenced by crushing and loss of aggregate at the road surface. (Molenaar et al, 2004) 2.9.3 Condition of the road surface The condition of wet road surfaces is interrupted by the contact between the tyre and the road surface and that leads to a decrease of the friction coefficient. Therefore, the rainwater has to be removed fast from the road surface so that the friction coefficient can be maintained at acceptable level. The applied percentage of crossfall of 2.5% is essential to remove rainwater on pavement. Dust and water acts as a lubricant on pavement is another factor of causing skid. Continuous rainfall can causes cleaning of the road surface and the friction coefficient is increased. (Molenaar et al, 2004) 25 2.9.4 Weather condition The influence of rainfall on pavement decreases the skidding resistance thus increases the risk for hydroplaning. Hydroplaning is a phenomenon where vehicle tyre looses contact with the road surface. Figure 2.6 schematically shows how a rubber tyre rolls or slides over a wet road surface. Three zones are distinguished: zone 1 (no contact), zone 2 (local contact) and zone 3 (dry contact). When zone 1 enlarges the friction coefficient decreases, finally resulting in aquaplaning. This effect is intensified if a standing wheel is brought to rotation very quickly; this occurs at a landing aircraft where the phenomenon of hydroplaning was observed first. (Molenaar et al, 2004) Figure 2.6: Schematic Representation of a Rolling Tyre on a Wet Road Surface (Molenaar et al, 2004) 26 2.10 Water Film Thickness The mitigation of hydroplaning and skidding depend solely on water film thickness on the pavement. The water film thickness depends on tendency water to drain effectively. According to David A. Noyce et.al. (2005), the water film thickness thickness is the thickness of the water film present on top of the pavement surface as illustrated in Figure 2.7. The flow path of the water on pavement is determined by the pavement surface slope. Measures to reduce water film thickness on pavement surface are alteration of surface geometry such as crossfall, use of permeable or porous asphalt paving mixtures, grooving in Portland cement concrete, and enhancement of surface texture through mixture selection and design. Figure 2.7: Water Film Thickness, Mean Texture Depth, and Total Flow 27 A research by Chesterton et.al, (2006) on aquaplaning and water film thickness towards slope, surface texture and rainfall intensity is done. This research proves that the water film thickness decreases when the surface texture depth increase shown in Figure 2.8. The water film thickness too decreases when the slope increase as shown in Figure 2.9. Besides that, Figure 2.10 shows when the rainfall intensity increase, the water film thickness increase too. However, this study suggested that the Gallaway (1979) method is better than the Road Research Laboratory in determining the water film thickness. Gallaway (1979) recommended that a maximum WFD of 4mm should be achieved. Figure 2.8: Water Film Depth vs Surface Texture Depth (Chesterton et.al, 2006) 28 Figure 2.9: Water Film Depth vs Slope (Chesterton et.al, 2006) Figure 2.10: Water Film Depth vs Rainfall Intensity (Chesterton et.al, 2006) 29 Another research by Stacy (2008) proves that the microtexture depth was negative trend which means that the increase in British Pendulum Number creates a lower water film thickness as shown in Figure 2.11 A lower water film thickness increase the microtexture of the mix. The same trend is seen for macrotexture. An increase in texture depth generates lower water film thickness. The relationship of macrotexture and water film thickness is depicted in Figure 2.12. Figure 2.11: Microtexture vs Film Thickness (Stacy, 2008) 30 Figure 2.12.: Macrotexture vs Film Thickness (Stacy, 2008) 2.11 Rainfall Simulator Precipitation is hard to obtain since the study is to be carried out in laboratory. Therefore, a Rainfall Simulator is developed to simulate the rain on pavement. Rainfall Simulator is a laboratory apparatus consists of three main components which are rain flowmeter to simulate rain, pavement mould to place pavement and adjustable gear to provide gradient or slope for the pavement. The purpose of Rainfall Simulator is to simulate rain on pavements. Rainfall simulator is as shown Figure 2.13 below. 31 Figure 2.13: Rainfall Simulator 2.12 Portable Skid Tester Portable Skid Tester is also known as British Pendulum Tester is used to measure the skidding characteristics on pavements. Guide on using the Portable Skid Tester is given in BS EN 13036-4. The Portable Skid Tester is as shown in Figure 2.14 below. Figure 2.14: Portable Skid Resistance Tester 32 CHAPTER III METHODOLOGY 3.1 Introduction This chapter focuses on the method and process to be carried out in order to achieve the objective of this study. Procedures discussed in this chapter are according to ASTM and AASHTO standard. All tests will be carried out in laboratory. There are six major parts of laboratory test to be conducted: 1) Design of Asphaltic Concrete mix 2) Sand Patch Test 3) Skidding test using Portable Skid Tester and Rainfall Simulator 4) Measurement of Water Film Thickness 5) Collection of runoff 6) Degree of Compaction 33 Determination of Low Rainfall, Medium Rainfall and High Rainfall Sieve Analysis Test (AC10, AC14, AC20) 2 years , 20 years and 100 years ARI Obtain Optimum Bitumen Content MASMA Rainfall Calculation & IDF Curve Design Asphaltic Concrete Mix (AC10,AC14 & AC20) Designed Rainfall Intensity (mm/hr) Construct Pavement Mixes (AC10, AC14, AC20) Designed Rainfall Flow Rate (ℓ/min) Sand Patch Test Continue Continue 34 Continued Continued Designed Flow Rate (ℓ/min) Constructed Pavement Mixes (AC10, AC14, AC20) Rainfall Simulator Adjustment of Crossfall Runoff Collector Basin Pavement Portable Skid Tester Obtain Q Runoff Obtain Water Film Thickness Obtain Pendulum Test Values Data Analysis Conclusion and Recommendation Figure 3.1: Flow of Laboratory Testing 35 3.2 Determination of Rainfall Intensity and Flowrate The rainfall intensities in Malaysia needs to be justify before conducting this study. Since the rainfall intensities varies from one year to another, the rainfall intensity could not be determined. Therefore, Manual Saliran Mesra Alam (MASMA) is used as guide to determine the low, medium and high rainfall intensity. The MASMA IDF curve is used to determine low intensity rainfall while the polynomial expression method is used for the medium and high rainfall intensities. The MASMA IDF Curve is shown as in Figure 3.2 below. Average Recurrence Interval (ARI) of two years is taken for low rainfall intensity while ARI of 20 years and 100 years is taken for medium and high rainfall intensity. Figure 3.2: MASMA IDF Curve for Kuala Lumpur (MASMA, 2000) A simple rainfall calculation and Rational Method calculation is done to obtain low rainfall intensity, medium rainfall intensity and high rainfall intensity values. The designed rainfall intensities is then converted to rainfall flowrates. The rainfall flowrates is then used as input in conducting the Rainfall Simulator. 36 3.3 Material Selection Aggregates, bitumen and filler are used in this study where aggregates of various sizes are obtained from a quarry in Ulu Choh, bituminous material of 80/100 PEN and Ordinary Portland Cement (OPC) used as filler. The aggregates need to fulfill the Polished Stone Value Test requirement in order to achieve a good resistance level of aggregate towards polishing while the bituminous material has to be tested with Penetration and Softening Point Test to fulfill the requirement so that an optimum mix can be acquired. 3.4 Sieve Analysis Sieve analysis test is used to determine the aggregate sizes from a sample taken from quarry. Through this sieve test, the proportion of coarse aggregates, fine aggregate and filler can be determined. The limit of the gradation used varies according to the function and purpose of the aggregate. The best aggregates sample sizes is the sample which best suits the ‘envelope’ through analysis. From this sieve analysis, the gradation obtained reflects the quality and the cost of the pavement. Standard procedures for sieve analysis are given in ASTM C 136 and AASHTO T 27. 37 3.4.1 Dry Sieve The apparatus that will be used for dry sieve analysis are: i. Sieve with various sizes; ii. Mechanical Sieve Shaker; and iii. Balance with the accuracy of 0.5g. The procedures for dry sieve analysis are as below: i. The sieve container is arranged in order of larger size to smaller size of opening. ii. Aggregate is placed on the top sieve and shaker is turned on to start the sieving. iii. Aggregate that has been sieved will be separated according to the size. iv. Total aggregate from different sizes as designed will be weigh for mixing. 38 3.5 Grade Selection Table 3.1: Gradation Limit For Asphaltic Concrete (JKR, 2005) Mix Type Wearing Course Wearing Course Wearing Course Mix Designation AC 10 AC 14 AC 20 BS Sieve Size, mm Percentage Passing ( by weight) 100 28.0 20.0 3.6 100 76-100 14.0 100 90-100 64-89 10.0 90-100 76-86 56-81 5.0 58-72 50-62 46-71 3.35 48-64 40-54 32-58 1.18 22-40 18-34 20-42 0.425 12-26 12-24 12-28 0.150 6-14 6-14 6-16 0.075 4-8 4-8 4-8 Blending of Stockpile Specimen The blending of stockpile specimen involves a combination of blending two or more aggregate stockpile together. This method is done by proportioning the aggregate in order to obtain the desired aggregate that suits the gradation limits. The gradation limits for three mix types are specified in Table 3.1. The mixes to be prepared includes aggregates, bitumen and OPC. The stockpiles used for this study are from 20mm, 10mm and quarry dust. The aggregate from respective stockpile is sieved and its passing weight is calculated to obtain the percentage of passing. Once stockpiles aggregate passing weight obtained, the proportion are made until it enters the gradation limits. 39 3.7 Optimum Bitumen Content The Optimum Bitumen Content of AC10, AC14 and AC20 were obtained from the Elizabeth (2006). OBC usually ranges from 4% to 7% The procedures for obtaining the Optimum Bitumen Content for 100 superpave gyrations shall comply to procedures based on Elizabeth (2006). 3.8 Mixing of Specimen Firstly, the total aggregate weight to be used is determined. Then, the aggregates samples are divided in four trays for every mix design and are place into the oven one day before the mixing process. This is to ensure that the aggregate is completely dry before the mixing process can take place. The temperature of the oven should be adjusted to 110º. Four hour before the sample mixing, the bitumen has to be heated in the oven for melting process. The temperature must be around 130 ºC - 145ºC. Once the mixing process take place, the aggregates from each tray is mixed with bitumen on a wok. Figure 3.3 shows the hot mixing process. When the mix is ready, it is filled into the rainfall simulator mould (118cm x 61cm x 6cm). The mixing process has to be carried out gradually between the four aggregate trays in order to maintain the heat of mix at 170 ºC while mixing and at 150 ºC for compaction besides providing a four layer mix into the rainfall simulator mould. The mixing process stated above is carried out for AC10, AC14 and AC20. 40 Figure 3.3: Hot Mixing of Aggregate and Bitumen 3.9 Compaction The compaction is carried out on each layer of mix placed into the rainfall simulator mould at 200 times compaction using a steel roller. A total of 800 times compaction effort is done on the mix to ensure that the 4% of air void could be achieved. The compaction is carried out at 150 º C. Figure 3.4 shows the compaction process using steel roller. Figure 3.4: Steel Roller Compactor 41 3.10 Pavement Mix Three different pavement mixes were constructed which are AC10, AC14 ad AC20 mixtures. Each mixes is placed on a 118cm x 61cm x 5cm mould. The mixes are left to cool in mould for one day as shown in Figure 3.5 and are ready to be placed into the Rainfall Simulator. Figure 3.5: Pavement Mix 3.11 Rainfall Simulator Test The sand patch test is carried out first before the rainfall simulation could take place. Five sand patch tests is carried out for each mix. Sand Patch Method is used to determine the texture depth of the constructed pavement mix. Once completed, the pavement is placed into the rainfall simulator apparatus and the Portable Skid Tester is placed on pavement to measure the Pendulum Test Value. The PTV is measured at normal conditions first where the procedures of measuring PTV follow the BS standard (BS13036, 2003) and no rainfall intensity is present. Next, Then, the PTV is measured according to the low rainfall intensity, medium 42 rainfall and high intensity using adjustable valve and flowmeter. The Portable Skid Tester is placed longitudinally with wheel path and against with the water runoff. The procedures of conducting the rainfall simulator are as follows: 1. Adjust the crossfall of the pavement ranging from 0% to 10% with the increase of 2% at a time. 2. Adjust the flowrate at the flowmeter using the valves according to the rainfall intensity. 3. Collect and measure the rainfall runoff collected. 4. Measure the water film thickness. 5. Calibrate the British Pendulum Tester 6. Obtain the Pendulum Test Value at 5 swings 7. Repeat Step 3 to Step 6 for different rainfall flowrate and at different crossfall. 3.12 Sand Patch Method Sand Patch test is used to determine texture depth of the road which is based on BS EN 13036-1:2002. The test procedure involves spreading a known volume of sand on a clean and dry pavement surface, measuring the area covered, and calculating the average depth between the bottom of the pavement surface voids and the tops of surface aggregate particles. Firstly, make sure the pavement surface to be measured and select a dry, homogeneous area that contains no unique, localized features such as cracks and joints. Then, the surface is cleaned using the stiff wire brush first and subsequently using the soft bristle brush to remove any residue, debris or loosely bonded aggregate particles from the surface. Locate the portable windshield around the test area if necessary. 43 Fill the cylinder of known volume with sand and gently tap the base of the cylinder several times on a rigid surface. Add more sand to fill the cylinder to the top, and level with a straightedge. Pour the measured volume or mass of sand on to the surface. The material is spread carefully into a circular patch, with the disc tool, rubber-covered side down, filling the surface voids flush with the aggregate particle tips. Use a slight pressure on the hand, just enough to ensure that the disc will spread out the sand so that the disc touches the surface aggregate particle tips. The diameter of the circular area covered by the sand is measured and recorded at a minimum of four equally spaced locations around the sample circumference. The average of four diameters data is calculated and recorded. This test procedure is repeated five times at the nearer location. The average of the individual values shall be considered to be the average surface texture (macrotexture) depth of the tested pavement surface. Figure 3.6 shows the sand patch test carried out on pavement mixes. The calculations involve for this test are calculation of the internal volume of the sample cylinder and calculation of the mean texture depth. Calculation of the internal volume of the sample cylinder: V = πd2h / 4 Where: V= internal cylinder volume, (mm3) d = internal cylinder diameter, (mm) h = cylinder height, (mm) 44 Calculation of the mean texture depth, MTD: MTD = 4V /πD2 Where: V = sample volume (internal cylinder volume), (mm3) D = average diameter of the area covered by the material, (mm) Figure 3.6: Sand Patch Test on Pavement Mixes 3.13 Pendulum Test Value The Portable Pendulum Tester is a dynamic pendulum impact type tester which is based on the energy loss occurring when a rubber slider edge is propelled across a test surface. The values measured are referred to as British Pendulum Numbers (BPN) for flat surfaces. 45 Firstly, the Portable Pendulum Tester is placed on a firm surface with the pendulum swinging in the direction of traffic. Then, the leveling screw is adjusted to make the pendulum support column in vertical. Then raise the axis of suspension of the pendulum for the arm swings freely. Adjust the friction in the pointer mechanism until the pointer arrive zero position on the test scale. Adjust the height of the pendulum arm so that in traversing the surface the rubber slider is in contact with it over the whole width of the slider and over the length below. A pointer fixed to the foot of the slider assembly and a pre-marked gauge shall be used. It must be careful not to disturb the slider from its set position. The pointer and the pendulum are released from horizontal position by holding the button. Catch the pendulum arm on the early portion of the return swing and record the position of the pointer on the scale to the nearest whole number. The pendulum and pointer returned to the release position by raising the slider using the lifting handle. This procedure performs for five times and re-wetting the surface again just before releasing the pendulum. Finally, the reading is recorded. The PTV value as the mean of five swings is calculated using the formula: PTV = ∑ ( v1 + v2 + v3 + v4 + v5 ) / 5 Where: v1, v2,v3,v4,v5 = individual values for each swing 46 3.14 Runoff Flowrate and Water Film Thickness The runoff flowrate and the water film thickness were obtained during the rainfall event on the rainfall simulator. The water film thickness is measured on the pavement where the water depth on the surface is measured using a ruler. The water runoff from the pavement is recorded for 1 minute. The water runoff value should be almost or closer to the flowrate of the rainfall since the air void of the asphaltic concrete is 4% only. Water runoff from the pavement is collected into the runoff collector basin and the volume is measured. The volume per minute is converted into liter per minute as a comparison with the flowrate of rainfall. 3.15 Core Specific Gravity and Degree of Compaction The specific gravity test is useful to determine the unit weight of compacted mixes. After completion of rainfall test on the three sample mixtures, the samples are then taken for coring. A total of five coring is done on each sample. The coring samples are let to dry for a day before the specific gravity test could be carried out. Bulk specific gravity is determined using the water displacement method. The specimens were weighed in three different conditions that is in air, in water, and saturated surface dry. The test is done to obtain the specific gravity of cored samples. Degree of Compaction of the mixes is acquired by obtaining the percentage of specific gravity of cored sample to the specific gravity of Superpave sample. The method to conduct the specific gravity is in accordance with ASTM D 2726. The cored samples for different mix is shown in Figure 3.7. 47 Below are the procedures for determining bulk specific gravity: i. Mass of specimen is immersed in water for 3 to 5 min and weigh. The weight mass in immersion is recorded as C. ii. Mass of saturated surface dry specimen in air – surface dry is recorded as B. The weight is taken after wiping the specimen surface that has been immersed in water previously. iii. Mass of oven-dry specimen – compacted specimens is the sample that is just left at room temperature. The mass is recorded as A. The bulk specific gravity for the specimens is calculated using the following equation: Bulk Specific Gravity = A/ (B-C) Where: A = Weight of dry specimen in air B = Weight of saturated surface dry specimen in air C = Weight of saturated specimen in water Figure 3.7: Cored Samples for Different Mixes 48 3.16 Analysis of Variance (ANOVA) Analysis of variance approach shows that the value of two or more unknown population means are likely to be different. In the case of analysis of variance, the following assumptions must be true: 1. The populations under the study have normal distributions. 2. The samples are drawn randomly and each sample is independent of the other samples. 3. The populations from which the sample values are obtained all have the same unknown population variance (б2). That is б12 = б22 = б32…… бn2 The procedures of conducting the ANOVA test are: 1. State the null and alternative hypotheses 2. Select the Level of Significance 3. Determine the test distribution to use 4. Define the rejection or critical region 5. State the decision rule 6. Compute the test statistics 7. Make the statistical decision 49 CHAPTER IV DATA AND ANALYSIS 4.1 Introduction Data is obtained from various guidelines before the results can be obtained. Results of this study are obtained through the various tests method stated in methodology. The results obtained are discussed in this chapter. Once the results are obtained, the analysis is done to describe the results obtained. Analysis of this study is focused on the relationship of three different factors affecting skidding. The relationship of rainfall intensity, surface texture and crossfall are obtained to evaluate the effect of those three factors on PTV. Besides that, analysis of variance (ANOVA) is carried out to determine the best pavement type and the best crossfall percentage to resist skid. 50 4.2 Sieve Analysis The sieve analysis results were obtained from the Elizabeth (2006). Sieve analysis results that are used in this study include the AC10, AC14 and AC20 gradation. The sieve analysis results are attached as in Appendix 1 and its gradation charts are shown in Figure 4.1 to Figure 4.3. Figure 4.1: Gradation for AC10 (Elizabeth, 2006) 51 Figure 4.2: Gradation for AC14 (Elizabeth, 2006) Figure 4.3: Gradation for AC20 (Elizabeth, 2006) 52 4.3 Wash Sieve The wash sieve is carried out to determine the amount of dust washed out from the aggregates. The wash sieve results were obtained from Elizabeth (2006). Wash sieve results of AC10, AC14 and AC20 were used in this study. The percentage of dust is 4.5% for AC10, 3.8% for AC 14 and 3.5% for AC20. The wash sieve results are attached in Appendix 2. 4.4 Penetration and Softening Point Test Bitumen obtained from a quarry in Sedenak was tested for penetration and softening point as soon as it arrives to the laboratory. Bitumen 80/100 PEN were tested for penetration test to determine the level of sample hardness while softening point test is done to obtain the temperature when the bitumen melts. The average penetration of the samples is 82.8 PEN while the average softening point temperature of the samples is 46.7 ºC. The penetration results met the JKR /SPJ/rev2005 requirement. Therefore, the bitumen can be used for mix. The results of both these tests are attached in Appendix 3. 4.5 Optimum Bitumen Content The Optimum Bitumen Content (OBC) was taken from Elizabeth (2006). The OBC of 6.3% for AC10, 5.8% for AC14 and 4.2% for AC20 were obtained through the 100 number of Superpave gyration which is compacted to 4% air void according to NAPA method. The Obtimum Bitumen Data is shows below in Table 4.1 53 Table 4.1: OBC, Gmb and TMD for 100 gyrations at 4% air void (Elizabeth, 2006) No of Gyration 100 4.6 Mix Type OBC (%) Gmb TMD AC10 6.3 2.278 2.391 AC14 5.8 2.297 2.400 AC20 4.2 2.352 2.443 Determination of Mass for Rainfall Simulator Mould Three samples have to be prepared for the rainfall simulator apparatus which are AC10, AC14 and AC20 respectively. The mass required for the mould rely on TMD and Air Void content. A simple calculation is done and resulted to the preparation of mass of 99.5kg for AC10, 100kg for AC14 and 101.5kg for AC20. The mass calculation is attached in Appendix 4. 4.7 Determination of Rainfall Using MASMA Three rainfall conditions were established for this study which are high rainfall intensity, medium rainfall intensity and low rainfall intensity. The high rainfall intensity of 432.40mm/hr at 100 years ARI, medium rainfall intensity of 220.50mm/hr at 20 years ARI and low rainfall intensity of 30mm/hr at 2 years ARI were obtained through calculation as attached in Appendix 5. All those three rainfall intensity in mm/hr are then converted into l/min so that to be used in rainfall simulator apparatus. The conversion of mm/hr to ℓ/min is done using the Rational Method of Q = C I A. The C value is 0.95 and the A value is 7.198 x 10-7 km2. Therefore, the high flowrate is 4.93 ℓ/min while the medium is 2.52 ℓ/min and the 54 low flowrate is 0.34 ℓ/min. Apart from that, a normal condition represents as the control where no rainfall intensity is present. 4.8 Determination of Pavement Crossfall The pavement crossfall for this study is subjected from 0% crossfall to 10% crossfall with the increment of 2% crossfall of every interval. The pavement crossfall can be determined by adjusting the lever gear installed at the back of the rainfall simulator apparatus. Pavement crossfall height and slope calculation is attached as in Appendix 6. 4.9 Polished Stone Value (PSV) The polished stone value test is conducted in order to determine the average value when aggregates are in polished condition. The results of aggregates from Ulu Choh quarry will provide the base value for this study which means that the value of a new constructed pavement must be higher than the polished stone value. The polishing stone value results are shown in Table 4.2. 55 Table 4.2: Polishing Stone Value Results Average last Average of four 3 readings consecutive specimen Specimen Measured Value 1 52,51,50,50,50 50 2 51,50,50,50,49 50 3 53,52,50,49,48 49 4 50,50,49,49,48 49 5 52,51,50,50,49 50 6 53,52,50,49,49 49 7 51,51,50,50,49 50 8 52,51,51,50,50 50 9 52,51,50,50,50 50 10 52,51,51,50,50 50 11 50,49,49,49,49 49 12 52,51,50,50,49 50 13 (Control) 53,52,51,51,50 51 Control Value 14 (Control) 53,52,51,50,50 50 50.5 The PSV for the sample 4.10 PSV 50 50 50 50 50 50 50 Sand Patch Test A total of five Sand Patch Tests is done for every sample. The average sand patch test for AC10 is 0.68mm, for AC14 is 0.96mm and for AC20 is 1.26mm.The sand patch test shows that bigger aggregate sizes has a bigger texture depth and the smaller aggregate sizes has a smaller texture depth. This proves that the macrotexture for AC20 is bigger and rougher than the macrotexture of AC14 followed by macrotexture of AC10. The results for the sand patch test are shown in Table 4.3, Table 4.4 and Table 4.5. The sand density and volume calculation is given in Appendix 7. 56 Table 4.3: Sand Patch Test Results for AC10 DIAMETER (mm) NO TEXTURE DEPTH 1 2 3 4 5 AVERAGE 1 200 220 200 200 210 206 0.73 2 230 220 210 220 215 219 0.64 3 200 200 200 210 225 207 0.72 4 210 220 225 215 225 219 0.64 5 220 210 225 210 225 218 0.65 AVERAGE 0.68 (mm) Table 4.4: Sand Patch Test Results for AC14 DIAMETER (mm) NO TEXTURE DEPTH 1 2 3 4 5 AVERAGE 1 160 165 165 155 165 162 1.17 2 170 170 170 170 170 170 1.07 3 185 195 205 190 200 195 0.81 4 180 200 195 180 200 191 0.84 5 170 185 190 180 190 191 0.92 AVERAGE 0.96 (mm) 57 Table 4.5: Sand Patch Test Results for AC20 DIAMETER (mm) NO 4.11 TEXTURE DEPTH 1 2 3 4 5 AVERAGE 1 160 165 150 160 160 159 1.22 2 155 150 150 150 150 151 1.35 3 150 150 155 155 150 152 1.33 4 160 165 160 170 155 162 1.17 5 165 150 150 165 165 159 1.22 AVERAGE 1.26 (mm) Pendulum Test Value The Pendulum Test Value is determined by three different independent variables from the rainfall simulator. The variables are the Rainfall Intensity, the Crossfall and the Surface Type. The Pendulum Test Value is obtained through three different type of rainfall intensity which are the low rainfall intensity (30mmh/r), medium rainfall intensity (220.5mm/hr) and high rainfall intensity (432.4mm/hr) and the normal condition where no rainfall intensity is present and the procedures of measuring PTV follow the BS standard (BS13036, 2003). Besides that, the crossfall ranging from 0% to 10% with 2% increase plays an important role in determining the Pendulum Test Value. Three types of surface type of AC10, AC14 and AC20 were used in this study to determine the differences surface texture and texture depth that could contribute to the variability of Pendulum Test Value. Therefore, the effect of rainfall intensity, crossfall and surface type on Pendulum Test Value is determined. A summary of the Pendulum Test Value is shown as in Table 4.6. The highest Pendulum Test Value of 58 99 is recorded for AC20 at the 30mm/hr rainfall intensity with 10% crossfall while the lowest Pendulum Test Value of 82 is recorded for AC10 at 432.4 mm/hr rainfall intensity with 0% crossfall. The PTV is high ranged at 82 to 99 because the constructed pavement is fresh and new where it provides high friction effect if compared to polished value which is only 50. The full results of Pendulum Test Value are attached in Appendix 8. Table 4.6: Pendulum Test Value for AC10, AC14 and AC20 Intensity Normal 30mm/hr 202.5mm/hr 432.4mm/hr Crossfall % 0 2 4 6 8 10 0 2 4 6 8 10 0 2 4 6 8 10 0 2 4 6 8 10 AC10 87 88 89 91 92 93 85 86 87 88 90 92 84 85 86 87 88 91 82 84 85 85 88 89 Pendulum Test Value AC14 87 89 90 92 93 94 86 87 89 91 93 94 84 85 87 90 92 93 82 84 87 89 91 92 AC20 89 91 92 95 98 99 87 88 91 95 98 99 85 86 89 92 95 97 84 85 88 92 94 96 59 4.11.1 The Effect of Rainfall Intensity on Pendulum Test Value Figure 4.4 to Figure 4.9 shows that the Pendulum Test Value decreases as the rainfall intensity increase for AC10, AC14 and AC20. The Pendulum Test Value decreases due to the excessive water on pavement surface during high rainfall intensity compared to the low rainfall intensity where only small water film thickness present on the pavement surface. This statement can be supported with research by Chesterton.J et.al. (2006) indicating that increase in intensity increases the water film thickness as shown in Figure 2.10. When there is a water film thickness on pavement, the energy produced by the rubber slider dissipates resulting to a smaller Pendulum Test Value. As the crossfall increases, the Pendulum Test Value increases for all three rainfall intensities. At 0% crossfall, the trendline for each surface type is close to each other. However, the trendline tends to move away within the three surface type. However, the trendline tends to move away within the three surface types when the crossfall increase. The effect of intensity is prominent at higher crossfall because small water film thickness is present on the surface because the macrotexture effectively drains off the water increasing microtexture thus resulting to a higher PTV value. 60 PTV vs Rainfall Intensity (0% Crossfall) y = -0.0075x + 85.372 R 2 = 0.9748 y = -0.0099x + 86.261 R 2 = 0.9991 y = -0.0074x + 87.019 R 2 = 0.952 88 87 PTV 86 AC10 85 AC14 84 AC20 83 82 81 0 100 200 300 400 500 Intensity (mm/hr) Figure 4.4: Pendulum Test Value vs Intensity at 0% Crossfall PTV vs Rainfall Intensity (2% Crossfall) 89 y = -0.005x + 86.13 R 2 = 0.9991 y = -0.0074x + 87.019 R 2 = 0.952 y = -0.0074x + 88.019 R 2 = 0.952 PTV 88 87 AC10 86 AC14 85 AC20 84 83 0 100 200 300 400 Intensity (mm/hr) Figure 4.5: Pendulum Test Value vs Intensity at 2% Crossfall 500 61 PTV PTV vs Rainfall Intensity (4% Crossfall) 92 91 90 89 88 87 86 85 84 y = -0.005x + 87.13 R 2 = 0.9991 y = -0.0049x + 88.777 R2 = 0.723 y = -0.0074x + 91.019 R 2 = 0.952 AC10 AC14 AC20 0 100 200 300 400 500 Intensity (mm/hr) Figure 4.6: Pendulum Test Value vs Intensity at 4% Crossfall PTV vs Rainfall Intensity (6% Crossfall) y = -0.0075x + 88.372 R 2 = 0.9748 y = -0.005x + 91.13 R2 = 0.9991 y = -0.0073x + 94.665 R2 = 0.723 96 PTV 94 92 AC10 90 AC14 88 AC20 86 84 0 100 200 300 400 Intensity (mm/hr) Figure 4.7: Pendulum Test Value vs Intensity at 6% Crossfall 500 62 PTV vs Rainfall Intensity (8% Crossfall) 100 y = -0.0049x + 89.777 R 2 = 0.723 y = -0.005x + 93.13 R 2 = 0.9991 y = -0.0098x + 97.907 R 2 = 0.9059 98 PTV 96 AC10 94 AC14 92 AC20 90 88 86 0 100 200 300 400 500 Intensity (mm/hr) Figure 4.8: Pendulum Test Value vs Intensity at 8% Crossfall PTV vs Rainfall Intensity (10% Crossfall) y = -0.0075x + 92.372 R 2 = 0.9748 y = -0.005x + 94.13 R2 = 0.9991 y = -0.0074x + 99.019 R 2 = 0.952 100 PTV 98 96 AC10 94 AC14 92 AC20 90 88 0 100 200 300 400 Intensity (mm/hr) Figure 4.9: Pendulum Test Value vs Intensity at 10% Crossfall 500 63 4.11.2 The Effect of Crossfall on Pendulum Test Value Figure 4.10 to Figure 4.12 shows that the Pendulum Test Value increase as the crossfall increases. The 10% crossfall shows a higher Pendulum Test Value compared to 0% crossfall. The 10% crossfall produces higher Pendulum Test Value because it is good in runoff and water drainage. Besides that, at 10% crossfall, the water film thickness is minimal between 0.5mm to 2.0mm compared to water film thickness of 2.0mm up to 7.0mm at 0% crossfall where waterponding occurs on the pavement surface. This statement can be justified by research carried out by Chesterton.J et.al. (2006) which shows that higher percentage of flow path slope generates smaller water film thickness as depicted in Figure 2.9. The 10% crossfall is good in water drainage even at high rainfall intensity. At 10% crossfall, the Pendulum Test Value is getting closer to the normal condition for different type of rainfall intensities for AC14 and AC20 indicating that the water film thickness is approaching to zero value and the runoff is efficient. However, for the 0% crossfall, the Pendulum Test Value does not get closer to the normal condition and has a big difference between low intensity, medium intensity and high intensity. At high rainfall intensity at 0% crossfall, the Pendulum Test Value is small because the water film thickness is big at 6mm to 7mm and the runoff of water from the pavement is not efficient. This creates a big gap of Pendulum Test Value against normal condition where there is no high water film present on pavement during normal condition. 64 y = 0.6286x + 86.857 R2 = 0.9878 PTV vs Crossfall (AC10) y = 0.6857x + 84.571 R2 = 0.9681 94 y = 0.6429x + 83.619 R2 = 0.9382 y = 0.6714x + 82.143 R2 = 0.942 92 PTV Value 90 Normal 30mm/hr 220.5mm/hr 88 86 432.4mm/hr 84 82 80 0 2 4 6 8 10 12 Crossfall (% ) Figure 4.10: Pendulum Test Value vs Crossfall for AC10 y = 0.7x + 87.333 R2 = 0.9847 PTV vs Crossfall (AC14) y = 0.8571x + 85.714 R2 = 0.989 96 y = 0.9857x + 83.571 R2 = 0.9786 94 y = 1.0429x + 82.286 R2 = 0.9823 PTV Value 92 Normal 30mm/hr 220.5mm/hr 432.4mm/hr 90 88 86 84 82 80 0 2 4 6 8 10 12 Crossfall (%) Figure 4.11: Pendulum Test Value vs Crossfall for AC14 65 y = 1.0571x + 88.714 R2 = 0.9779 PTV vs Crossfall (AC20) y = 1.3429x + 86.286 R2 = 0.971 105 y = 1.2857x + 84.238 R2 = 0.9862 y = 1.3x + 83.333 R2 = 0.979 PTV Value 100 Normal 30mm/hr 220.5mm/hr 432.4mm/hr 95 90 85 80 0 2 4 6 8 10 12 Crossfall (%) Figure 4.12: Pendulum Test Value vs Crossfall for AC20 4.11.3 The Effect of Surface Texture on Pendulum Test Value Figure 4.13 to Figure 4.18 shows that increase in the texture depth resulted to increase in the Pendulum Test Value. This is due to the influence of macrotexture effect and microtexture effect on the aggregate surface. When the texture depth of the pavement increases, the macrotexture plays an important role in draining off the water. High in texture depth which is also high in macrotexture provides better drainage which reduces the water film thickness on pavement creating higher microtexture which increases the PTV. Study by Chesterton et.al. (2006) as in Figure 2.8 also proves that bigger macrotexture creates smaller water film thickness. Another study by Stacy G. Williams (2008) on macrotexture and microtexture effect on water film thickness as depicted in Figure 2.11 and Figure 2.12 also proves that high in British Pendulum 66 Number and macrotexture creates a smaller water film thickness. AC20 represents bigger texture depth while the AC10 represents a smaller texture depth. On 0% crossfall, the Pendulum Test Value is the least compared to the Pendulum Test Value for 10% crossfall which is the highest. At 0% crossfall, water tends to fill up the macrotexture affecting the texture depth. Therefore, the macrotexture of the smallest texture depth of AC10 is filled with water faster than the AC20 because its texture depth is smaller. Apart from that, the AC10 does not have a good macrotexture as the AC20 which is important in draining water and keeping the aggregates in contact with tyre. At 10% crossfall, water is drained out faster and more efficiently producing a bigger Pendulum Test Value. In conjunction to that, the trendline slope of 10% crossfall is much steeper than the 0% crossfall. This proves that the Pendulum Test Value shows big differences at 10% crossfall for AC10, AC14 and AC20. However, at 0% crossfall, the trendline is not very steep and the difference of Pendulum Test Value for AC10, AC14 and AC20 is not that significant. At 0% crossfall, since the runoff is slow and the water film is present, the AC10, AC14 and AC20 do not show a big difference in Pendulum Test Value. However, at 10% crossfall when the water runoff is fast and the water film thickness is small, the AC20 tends to produce better Pendulum Test Value since the bigger macrotexture or bigger texture depth is capable of draining the water efficiently. Therefore, the PTV was found to be the best at the condition of 10% crossfall with high texture depth type of surface. 67 Figure 4.13: Pendulum Test Value vs Texture Depth at 0% Crossfall Figure 4.14: Pendulum Test Value vs Texture Depth at 2% Crossfall 68 Figure 4.15: Pendulum Test Value vs Texture Depth at 4% Crossfall Figure 4.16: Pendulum Test Value vs Texture Depth at 6% Crossfall 69 Figure 4.17: Pendulum Test Value vs Texture Depth at 8% Crossfall Figure 4.18: Pendulum Test Value vs Texture Depth at 10% Crossfall 70 4.12 Runoff and Water Film Thickness Data Table 4.6 shows the water film thickness and the runoff flowrate of various surface type and at various crossfall. The water film thickness is significant from 0% crossfall to 10% crossfall. The highest water film thickness exist at 0% crossfall because there is waterponding exist compared to 10% crossfall where water drainange is good. However, the water film thickness only differs a little from AC10, AC14 to AC20. This is because the water film thickness is so small ranging from 0mm to 7mm only throughout the rainfall test. Therefore, the difference between each surface type is small. Apart from that, the water film thickness is measured using a ruler which is not that accurate in readings. The water runoff varies from 0% crossfall to 10%. The higher runoff was noticed to be at 10% crossfall since it drains the water faster and more efficient. However, the 0% crossfall has the least water runoff value due to water accumulating on the surface and ponding. The high rainfall intensity produces high water film thickness and high runoff. Table 4.7 shows the water film thickness and the water runoff results. 71 Table 4.7: The Water Film Thickness and The Runoff of AC10, AC14 and AC20 Rainfall Crossfall Intensity (%) AC10 AC14 AC20 Water Film Q Water Film Q Water Film Q Thickness(mm) runoff Thickness(mm) runoff Thickness(mm) runoff (ℓ/min) (ℓ/min) (ℓ/min) 0 2.0 0.26 2.0 0.26 2.0 0.26 2 1.5 0.26 1.5 0.26 1.5 0.26 30 4 1.5 0.26 1.5 0.26 1.5 0.26 mm/hr 6 1.0 0.52 1.0 0.52 1.0 0.52 8 1.0 0.52 1.0 0.52 1.0 0.52 10 0.5 0.52 0.5 0.52 0.5 0.52 0 4.0 2.10 3.0 2.10 3.0 2.10 2 3.0 2.10 2.5 2.10 2.5 2.10 202.5 4 2.5 2.10 2.5 2.10 2.5 2.10 mm/hr 6 2.0 2.36 2.0 2.36 2.0 2.36 8 1.5 2.36 1.5 2.36 1.5 2.36 10 1.0 2.62 1.0 2.62 1.0 2.62 0 7.0 4.72 6.0 4.72 6.0 4.72 2 6.0 4.72 5.0 4.72 5.0 4.72 432.4 4 5.0 4.98 5.0 4.98 4.0 4.98 mm/hr 6 4.0 4.98 4.0 4.98 3.0 4.98 8 3.0 5.24 3.0 5.24 3.0 5.24 10 2.0 5.24 2.0 5.24 2.0 5.24 4.13 Degree of Compaction and Specific Gravity The degree of compaction is carried to assure that the 4% air void is maintained. The compaction of the samples is done at 800 roll using the compaction roller. Degree of compaction is obtained through the specific gravity of cored sample 72 and specific gravity superpave. Table 4.8 shows the average degree of compaction of each mix type.The degree of compaction for AC10 meets the specification of 98%100% degree of compaction for wearing course. However, the degree of compaction for AC20 did not meet the specification. Therefore, permeability test is done on AC20 cored samples to investigate the possibility of water infiltrating through the samples which could decrease the degree of compaction value. The permeability test results are shown in Table 4.9.Based on permeability result from Table 4.9, the average k value of AC20 mix which is 433 x 10-5 cm/s is bigger than 125 x 10-5 cm/s which proves that the AC20 is permeable. The AC20 samples is permeable due to insufficient compaction effort creating bigger air voids which eventually led to the smaller percentage in degree of compaction. Table 4.8:The Specific Gravity and the Degree of Compaction of AC10, AC14,AC20 Mix Type AC10 AC14 AC20 Air (g) SSD (g) Water (g) SG Core SG Superpave 1007.9 1008.8 560.1 2.246 99 1107.7 1108.4 614.4 2.242 98 1100.1 1101.1 610.0 2.240 1078.7 1079.9 595.9 2.229 98 1074.0 1074.8 598.0 2.253 99 1079.1 1083.6 597.5 2.220 97 942.2 949.0 525.0 2.222 97 1131.4 1135.5 630.3 2.240 994.1 997.1 556.5 2.256 98 1129.4 1133.5 630.0 2.243 98 1029.7 1037.9 580.8 2.253 96 1116.6 1118.7 625.3 2.263 96 1158.7 1162.7 655.7 2.285 1135.1 1141.9 636.6 2.246 96 1081.4 1086.6 606.0 2.250 96 2.278 2.297 2.352 DOC(%) Average 98 97 97 98.4 97.4 96.2 73 Table 4.9: Permeability Test Result of AC20 A (cm2) L (cm) A (cm2) T (s) h1 (cm) h2 (cm) K (cm/s) 7.070 6.400 78.550 11.000 67.000 62.000 0.00406 7.070 6.800 78.550 11.000 67.000 62.000 0.00432 7.070 7.000 78.550 12.000 67.000 62.000 0.00407 7.070 7.000 78.550 10.000 67.000 62.000 0.00489 7.070 6.800 78.550 11.000 67.000 62.000 0.00432 Average 0.00433 4.14 Analysis of Variance (ANOVA) Results ANOVA is carried out to determine the factors affecting PTV differs or otherwise according to the variables. The summary of ANOVA results on each factor is shown in Table 4.10 to Table 4.15 below. The complete analysis of ANOVA is attached in Appendix 9. The table 4.10 shows that at 0% and 2% crossfall, there is a significant difference between the three types of intensities condition. This proves that at 0% crossfall and at 2% crossfall, the differences in intensities affect the Pendulum Test Value. However, at 4%, 6%, 8% and 10% crossfall, there is no significant differences can be noticed between the three rainfall intensities. This means that the Pendulum Test Values does not vary much between the three rainfall intensities at 4% to 10% crossfall. Besides that, insignificant PTV value between low rainfall intensity to high rainfall intensity proves that the water even at high rainfall intensity could be drained efficiently reducing the water film thickness on the pavement. 74 Based on the ANOVA analysis, the range from 4% to 10% crossfall have proven to be efficient in draining water. However, the 10% crossfall could not be implemented on roads construction because it affects the driver’s comfort and the driving maneuver. Therefore, the 4% crossfall can be suggested to be implemented for future road construction since it also has a good drainage effect to resist skid. Table 4.10: ANOVA of Rainfall Intensity on Crossfall Variables Pvalue Pcrit Condition Significant Remarks 0% crossfall 0.014247 0.05 P < Pcrit Yes Reject Ho, Accept H1 2% crossfall 0.012875 0.05 P < Pcrit Yes Reject Ho, Accept H1 4% crossfall 0.296296 0.05 P > Pcrit No Accept Ho, Reject H1 6% crossfall 0.615448 0.05 P > Pcrit No Accept Ho, Reject H1 8% crossfall 0.651732 0.05 P > Pcrit No Accept Ho, Reject H1 10% crossfall 0.650963 0.05 P > Pcrit No Accept Ho, Reject H1 Table 4.11 shows no significant differences were noticed on PTV between rainfall intensities for AC10, AC14 and AC20. However, AC20 has the highest Pvalue towards rainfall intensities which proves that the AC20 is the least significant towards the three rainfall intensities because the water film thickness of AC20 is lesser due to the high texture depth it has to drain water efficiently. Table 4.11: ANOVA of Rainfall Intensity on Surface Type Variables Pvalue Pcrit Condition Significant Remarks AC10 0.269631 0.05 P > Pcrit No Accept Ho, Reject H1 AC14 0.504632 0.05 P > Pcrit No Accept Ho, Reject H1 AC20 0.531881 0.05 P > Pcrit No Accept Ho, Reject H1 Table 4.12 shows PTV of 30mm/hr, 202.5mm/hr and 432.4mm/hr rainfall intensities has significant difference between crossfall. 30mm/hr recorded the least 75 significant since 30mm/hr produces small water film thickness on pavement giving the almost similar PTV readings. Table 4.12: ANOVA of Crossfall on Rainfall Intensity Variables Pvalue Pcrit Condition Significant Remarks 30mm/hr 0.010865 0.05 P < Pcrit Yes Reject Ho, Accept H1 202.5mm/hr 0.001834 0.05 P < Pcrit Yes Reject Ho, Accept H1 432.4mm/hr 0.003194 0.05 P < Pcrit Yes Reject Ho, Accept H1 Table 4.13 shows that the Pendulum Test Value of all three AC10, AC14 and AC20 has significant difference towards increase percentage of the crossfall. This proves that as the crossfall increases, there is increase on the Pendulum Test Value indicating good skidding resistance. This means that the AC10, AC14 and AC20 is good in resisting skid when the crossfall gets bigger. However, AC20 is the best surface type to drain water due to the higher macrotexture it has. AC20 proves to be the best surface type since the Pvalue of AC20 recorded the least value proving that AC20 is the significantly high towards crossfall from the ANOVA analysis. Table 4.13: ANOVA of Crossfall on Surface Type Variables Pvalue Pcrit Condition Significant Remarks AC10 0.001384 0.05 P < Pcrit Yes Reject Ho, Accept H1 AC14 2.36E-06 0.05 P < Pcrit Yes Reject Ho, Accept H1 AC20 5.24E-07 0.05 P < Pcrit Yes Reject Ho, Accept H1 Table 4.14 shows PTV of 30mm/hr, 202mm/hr and 432.4 mm/hr rainfall intensities has no significant between surface type. However, the 30mm/hr rainfall intensity shows a slightly higher differences between AC10, AC14 and AC20 because it produce only a small water film thickness and the surface texture plays a 76 more important role. However, with the largest rainfall intensity, coarser surface texture covered by water. Table 4.14: ANOVA of Surface Type on Rainfall Intensity Variables Pvalue Pcrit Condition Significant Remarks 30mm/hr 0.104239 0.05 P > Pcrit No Accept Ho, Reject H1 202.5mm/hr 0.248989 0.05 P > Pcrit No Accept Ho, Reject H1 432.4mm/hr 0.19509 0.05 P > Pcrit No Accept Ho, Reject H1 Table 4.15 shows that 0% and 2% crossfall has no significant differences on PTV between surface type. This proves that 4% to 10% crossfall drains water efficiently providing different PTV according to the surface type where the surface texture plays an important role in determining PTV. Table 4.15: ANOVA of Surface Type on Crossfall Variables Pvalue Pcrit Condition Significant Remarks 0% crossfall 0.489078 0.05 P > Pcrit No Accept Ho, Reject H1 2% crossfall 0.506023 0.05 P > Pcrit No Accept Ho, Reject H1 4% crossfall 0.046258 0.05 P < Pcrit Yes Reject Ho, Accept H1 6% crossfall 0.005248 0.05 P < Pcrit Yes Reject Ho, Accept H1 8% crossfall 0.003613 0.05 P < Pcrit Yes Reject Ho, Accept H1 10% crossfall 0.002843 0.05 P < Pcrit Yes Reject Ho, Accept H1 77 CHAPTER V CONCLUSION AND RECOMMENDATIONS 5.1 Conclusion Based on the results above, the following conclusions can be made: The Pendulum Test Value on 432.4mm/hr intensity is smaller than the Pendulum Test Value of 220.5mm/hr and 30mm/hr. The 30mm/hr Pendulum Test Value has the highest Pendulum Test Value because of the existence of small water film thickness on the pavement. The Pendulum Test Value for 0% crossfall is smaller than the 10% crossfall. The 10% crossfall has a greater Pendulum Test Value because it is efficient in water drainage creating smaller water film thickness thus resulting to a bigger PTV. However, the 10% crossfall could not be implemented since it affects the driver’s comfort. Therefore, this study recommend 4% crossfall since the ANOVA results proved that crossfall ranging from 4% to 10% is efficient in water drainage from the pavement. 78 The Pendulum Test Value for AC20 is bigger than the AC14 and AC10. This is because the AC20 surface texture is rough and good in water drainage since it has a high macrotexture depth. 5.2 Recommendation It is recommended that this study is continued with a broader scope since this study can provide a good knowledge on skidding. The recommendations to further this regarding the factors affecting Pendulum Test Value are as follows: 1. Stone Mastic Asphalt mixes and Porous Asphalt mixes are recommended to further investigate the factors affecting Pendulum Test Value since this study is only limited to Asphaltic Concrete mixes only. Besides that, it is suggested to expand the scope of this study by introducing the rigid pavement mixes and surface dressing mixes. These will provide a good comparison of different types of mixes besides obtaining the best mix type that resist skidding. 2. This study only uses three different rainfall conditions which are low rainfall intensity, medium rainfall intensity and high rainfall intensity. It is recommended that the intensities could be varied to at least five rainfall conditions to provide a good relationship against Pendulum Test Value. 3. Dynamic load or tyre is suggested to be located into the rainfall simulator in order to obtain speed that could cause hydroplaning and skidding since speed is one of the major contributors to skidding during rainy climate. 79 4. A better measurement tool is suggested to replace the use of ruler to measure the water film thickness and the runoff depth to produce an accurate reading during the event of rainfall. REFERENCES American Association of State Highway and Transportation Officials, “A Policy on Geometric Design of Highways and Streets” 1990 ASCE, Design Manual for Storm Drainage, American Society of Civil Engineers, New York, 1960. British Pendulum Manual, Operation manual of the British Pendulum SKID resistance tester. United Kingdom:Wessex Engineering Ltd. 2000. British Standards Institution. BS EN 13036-4. Method for measurement of slip/skid resistance of a surface – The Pendulum Test. London: British Standards Institution. 2003 Brouwer et.al (1985), Introduction to Irrigation, Food And Agriculture Organization Of The United Nations (FAO), Rome, Italy Chesterton.J et.al. (2006). The Use of the Gallaway Formula for Aquaplaning Evaluation in New Zealand, Transportation and the Pursuit of Excellence, NZIHT & Transit NZ 8th Annual Conference. 81 David A. Noyce et.al. (2005), Incorporating Road Safety Into Pavement Management: Maximizing Asphalt Pavement Surface Friction For Road Safety Improvements, Midwest Regional University Transportation Center, Traffic Operations and Safety (TOPS) Laboratory. Elizabeth Chong Eu Mee (2006). The Effects Of Nominal Maximum Aggregate Size On The Properties of HMA Using Gyrotory Compactor. Universiti Teknologi Malaysia.Master Project Report. Flintsch G.W et al. Effect of HMA Properties on Pavement Surface Characteristics. Department of Civil and Environmental Engineering, Virginia Polytechnic Institute and State University. Gallaway, B. M., et. al., (1979). Pavement and Geometric Design Criteria for Minimizing Hydroplaning, Federal Highway Administration, Report No. FHWA-RD-79-31. Garrabrant.R, (2004), Highway Engineering, Standard Handbook for Civil Engineering, McGraw Hill. Jabatan Kerja Raya (JKR), A Guide on Geometric Design of Roads, Arahan Teknik Jalan (8/86), Public Works Department Malaysia. 1986 Jabatan Kerja Raya. Standard Specification for Road Works. Kuala Lumpur. JKR/SPJ. 1998-rev 2005 82 Kennedy, C.K., Young, A.E., Butler, I. C. (1990). Measurement of Skidding Resistance and Surface Texture and the Use of Results in the United Kingdom. ASTM STP 1031, Philadelphia, U.S.A. Kenneth Young et al. (2004), Hydraulic Design of Drainage for Highways, Hydraulic Design Handbook, McGraw Hill. Kokkalis. A.G. Tsohos. G.L, Panagoul.O.K, (2002), Consideration of Fractals Potential in Pavement Skid Resistance Evaluation. Journal of Transportation Engineering. Manual Saliran Mesra Alam, Design Rainfall, Urban Stromwater Management Manual, Kuala Lumpur, Malaysia: JPS Malaysia Chapter 13.Pg 13-4. 2000 Molenaar et.al, (2004). Geometric and structural design of roads and railways: Structural design of roads. CT3041. United Kingdom Nor Zolhanita Binti Ahmad Tarmidi (2007). Penilaian Terhadap Campuran Halus Gred Terbuka. Universiti Teknologi Malaysia.Degree Project Report. Peter Cairney et.al. (2006), A pilot study of the effects of macrotexture on stopping distance, Atsb Transport Safety REPORT CR 226, Australian Transport Safety Bureau, Australia. 83 Rebecca S. Mc Daniel. (2004). Field Evaluation of Porous Asphalt Pavement. United States. North Central Superpave Center Roberts,F.L., P.S., Brown, E.R., Lee, Y.D.,Kennedy, T.W, (1996), ‘Hot-Mix Asphalt Materials, Mixture Design and Construction’, Napa Research and Education Foundation. Royal Malaysia Police, Road Accident Statistical Report, Road Traffic Branch, Bukit Aman. 2005. Sandberg U. (1997). Influence on Road Surface Texture on Traffic Characteristics Related to Environment, Economy, and Safety. A State-of-the-art Study Regarding Measures and Measuring Methods. Swedish National Road and Transport Research Institute. Stacy G. Williams (2008). Surface Friction Measurements of Fine-Graded Asphalt Mixtures, Mack-Blackwell Transportation Center 2066, Arkansas. Final Report 84 APPENDIX 1 SIEVE ANALYSIS GRADATION Percentage Passing (by weight) Mix Design AC10 AC14 AC20 BS Sieve ^0.45 LL Gradation UL LL Gradation UL LL Gradation UL 28 4.479 - - - - - - 100 100 100 20 3.85 - - - 100 100 100 76 94 100 14 3.279 100 100 100 90 93 100 64 80 89 10 2.818 90 95 100 76 79 86 56 72 81 5 2.063 58 65 72 50 56 62 46 58 71 3.35 1.723 48 56 64 40 47 54 32 49 58 1.18 1.077 22 27 40 18 23 34 20 33 42 0.425 0.68 12 15 26 12 14 24 12 22 28 0.15 0.426 6 10 14 6 10 14 6 12 16 0.075 0.312 4 6 8 4 6 8 4 6 8 LL – Lower Limit UL – Upper Limit 85 APPENDIX 2 WASH SIEVE Mix AC10 Sample AC14 AC20 I II I II I II Mass Before Washing g 1128.0 1128.0 1128.0 1128.0 1128.0 1128.0 Mass After Washing g 1079.3 1076.0 1084.3 1086.1 1087.5 1090.0 Mass of Dust g 48.7 52.0 43.7 41.9 40.5 38.0 Average g 50.4 42.8 39.3 Percentage % 4.5 3.8 3.5 205.3 174.5 160.1 Weight of Dust for 4600g g 86 APPENDIX 3 PENETRATION AND SOFTENING TEST Penetration Test 1 2 3 4 5 Average Sample 1 82 83 82 84 83 82.8 Sample 2 84 82 83 83 83 83.0 Sample 3 82 84 82 82 83 82.6 Average Penetration 82.8 PEN Softening Point Test Ball A Ball B Average Temperature Sample 1 47.0 47.5 47.3 Sample 2 46.0 46.0 46.0 Average Temperature 46.7 ºC 87 APPENDIX 4 MASS FOR RAINFALL SIMULATOR MOULD Mass/Volume = (100 – Air void)/100 x TMD Volume = 118cm x 61cm x 6cm = 43188cm3 ACW 14 Mass/43188 = (100 – 4)/100 x 2.400 = 100.0kg ACW 20 Mass/43188 = (100 – 4)/100 x 2.443 = 101.5kg 88 ACW 10 Mass/43188 = (100 – 4)/100 x 2.391 = 99.5kg ACW 10 Aggregate Bitumen (Total Mix Mass = 99.5kg) 93.700 x 99.5 = 93.232 kg 6.300 x 99.5 = 6.269 kg Mass Sieve % Size Passing % Retained 14.000 100.000 - 10.000 95.000 5.000 4.662 kg 5.000 65.000 30.000 27.969 kg 3.350 56.000 9.000 8.391 kg 1.180 27.000 29.000 27.037 kg 0.425 15.000 12.000 11.188 kg 0.150 10.000 5.000 4.662 kg 0.075 6.000 4.000 3.729 kg Pan - 6.000 5.594 kg 100.000 93.232 kg Total Required - kg 89 ACW 14 Aggregate Bitumen (Total Mix Mass = 100.0kg) 94.200 x 100 = 94.200 kg 5.800 x 100 = 5.800 kg Sieve % Size Passing % Retained 20.000 100.000 - 14.000 93.000 7.000 6.594 kg 10.000 79.000 14.000 13.188 kg 5.000 56.000 23.000 21.666 kg 3.350 47.000 9.000 8.478 kg 1.180 23.000 24.000 22.608 kg 0.425 14.000 9.000 8.478 kg 0.150 10.000 4.000 3.768 kg 0.075 6.000 4.000 3.768 kg Pan - 6.000 5.652 kg 100.000 94.200 kg Total Mass Required - kg 90 ACW 20 Aggregate Bitumen (Total Mix Mass = 101.5kg) 95.800 x 101.5 = 97.237 kg 4.200 x 101.5 = 4.263 kg Sieve % Size Passing % Retained 28.000 100.000 - 20.000 94.000 6.000 5.834 kg 14.000 80.000 14.000 13.613 kg 10.000 72.000 8.000 7.779 kg 5.000 58.000 14.000 13.613 kg 3.350 49.000 9.000 8.751 kg 1.180 33.000 16.000 15.558 kg 0.425 22.000 11.000 10.696 kg 0.150 12.000 10.000 9.724 kg 0.075 6.000 6.000 5.834 kg Pan - 6.000 5.834 kg 100.000 97.237 kg Total Mass Required - kg 91 APPENDIX 5 RAINFALL DESIGN AND RATIONAL METHOD Rainfall Design using MASMA Design values are taken for Kuala Lumpur at duration time of 5 minutes. For ARI =100 Years Design Storm ln(It) = a + b (ln t) + c (ln t)2 + d (ln t)3 a = 5.0064 b = 0.8709 c = -0.3070 d = 0.0186 ln I30 = 5.1490 I30 = 172.24 mm/hr P30 = 86.12 mm ln I60 = 4.702 I60 = 110.20 mm/hr P60 = 110.20 mm FD = 2.08 (Table 13.3) PD = P30 – FD (P60 – P30) 100 P5 = 86.12 – 2.08 (110.20 – 86.12) = 36.03 mm 100 I5 = 36.03 / (1/12) = 432.40 mm/hr 92 Design values are taken for Kuala Lumpur at duration time of 15 minutes. For ARI = 20 Years Design Storm ln(It) = a + b (ln t) + c (ln t)2 + d (ln t)3 a = 4.9781 b = 0.7533 c = -0.2796 d = 0.0166 ln I30 = 4.959 I30 = 142.4 mm/hr P30 = 71.2 mm ln I60 = 4.515 I60 = 91.3 mm/hr P60 = 91.3 mm FD = 0.8 (Table 13.3) PD = P30 – FD (P60 – P30) 20 P15 = 71.20 – 0.8 (91.30 – 71.20) = 55.12 mm 20 I15 = 55.12 / (1/4) = 220.48 mm/hr Data taken from IDF Curve (MASMA) for duration 30 min and above. For ARI = 2 Years Design Storm Intensity100 = 30 mm/hr Rational Method Calculation Q = 0.278 C I A C = 0.95 93 High Intensity100 Medium Intensity20 = 432.40 mm/hr = 220.48 mm/hr Low Intensity2 Area = 30 mm/hr = 1.18m x 0.61m = 0.00118km x 0.00061km =7.2 x 10-7 km2 High Intensity Flowrate 100 Q5 = 0.278 x 0.95 x 432.40 x (7.2 x 10-7) = 8.222 x 10-5 m3/s = 0.082 ℓ /s = 4.93 ℓ/min Medium Intensity Flowrate 20 Q5 = 0.278 x 0.95 x 220.48 x (7.2 x 10-7) = 4.192 x 10-5 m3/s = 0.042 ℓ /s = 2.52 ℓ/min Low Intensity Flowrate 2 Q100 = 0.278 x 0.95 x 30 x (7.2 x 10-7) = 5.704 x 10-6 m3/s = 5.704 x 10-3 ℓ /s = 0.34 ℓ/min Therefore; The acceptable range for design rainfall flow rate = 0.3ℓ/min to 5ℓ/min 94 APPENDIX 6 PAVEMENT CROSSFALL 2% Crossfall 2 / 100 = X / 0.61 X = 0.0122m = 1.22cm X 0.61 4% Crossfall 8% Crossfall 4 / 100 = X / 0.61 8 / 100 = X / 0.61 X = 0.0244m = 2.44cm X = 0.0488m = 4.88cm 6% Crossfall 10% Crossfall 6 / 100 = X / 0.61 10 / 100 = X / 0.61 X = 0.0366m = 3.66cm X = 0.061m = 6.10cm 95 APPENDIX 7 SAND DENSITY AND VOLUME CALCULATION The procedure of calculating sand volume and density are as follows: Mass of Mould = 35.2g Mass of Mould + Sand = 65.5g Mass of Sand = 30.3g Mass of Mould + Water = 59.4g Mass of Water = 24.2g Assumption: Volume of water = Volume of sand Volume of water = Mass of water / Density of water = 24.2 g / 1000 kg/m3 = 0.0000242 m3 Volume of sand = Volume of water = 0.0000242 m3 Density of sand = Mass of sand / Volume of sand = 30.3 g / 0.0000242 m3 = 1252kg/ m3 APPENDIX 8 PENDULUM TEST VALUE Normal Condition (AC10) Crossfall (%) PTV Temperature Correction Corrected 1 2 3 4 5 Average ºC Factor PTV 0 86 86 85 85 84 85 33 +2 87 2 87 87 86 86 86 86 33 +2 88 4 88 88 87 87 87 87 33 +2 89 6 89 89 89 88 88 89 33 +2 91 8 91 91 90 90 90 90 33 +2 92 10 91 91 91 91 91 91 33 +2 93 97 30mm/hr Rainfall Intensity Condition (AC10) Crossfall (%) PTV Temperature Correction Corrected 1 2 3 4 5 Average ºC Factor PTV 0 83 83 83 83 83 83 32 +2 85 2 84 84 84 83 83 84 32 +2 86 4 85 85 85 85 84 85 32 +2 87 6 87 86 86 86 86 86 32 +2 88 8 88 88 88 88 88 88 32 +2 90 10 90 90 90 89 89 90 32 +2 92 220.5mm/hr Rainfall Intensity Condition (AC10) Crossfall (%) PTV Temperature Correction Corrected 1 2 3 4 5 Average ºC Factor PTV 0 82 82 82 82 81 82 32 +2 84 2 84 84 83 83 83 83 32 +2 85 4 85 85 85 84 83 84 32 +2 86 6 86 85 85 85 85 85 32 +2 87 8 87 87 86 86 86 86 32 +2 88 10 89 89 89 88 88 89 32 +2 91 98 432.4mm/hr Rainfall Intensity Condition (AC10) Crossfall (%) PTV Temperature Correction Corrected 1 2 3 4 5 Average ºC Factor PTV 0 81 80 80 80 80 80 31 +2 82 2 83 82 81 81 81 82 31 +2 84 4 83 83 83 82 82 83 31 +2 85 6 84 83 83 83 83 83 31 +2 85 8 87 86 85 85 85 86 31 +2 88 10 88 88 88 87 86 87 31 +2 89 Normal Condition (AC14) Crossfall (%) PTV 1 Temperature Correction Corrected 2 3 4 5 Average ºC Factor PTV 0 85 85 85 85 85 85 29 +2 87 2 87 87 87 86 86 87 29 +2 89 4 88 88 88 88 87 88 29 +2 90 6 90 90 90 89 89 90 29 +2 92 8 92 92 91 91 91 91 29 +2 93 10 93 93 92 92 92 92 29 +2 94 99 30mm/hr Rainfall Intensity Condition (AC14) Crossfall (%) PTV 1 Temperature Correction Corrected 2 3 4 5 Average ºC Factor PTV 0 84 84 84 83 83 84 29 +2 86 2 85 85 85 85 85 85 29 +2 87 4 87 87 87 86 86 87 29 +2 89 6 90 90 89 89 89 89 29 +2 91 8 92 92 91 91 90 91 29 +2 93 10 93 93 92 92 92 92 29 +2 94 220.5mm/hr Rainfall Intensity Condition (AC14) Crossfall (%) PTV 1 Temperature Correction Corrected 2 3 4 5 Average ºC Factor PTV 0 82 82 82 82 82 82 29 +2 84 2 84 84 83 83 83 83 29 +2 85 4 86 86 85 85 85 85 29 +2 87 6 89 89 88 88 88 88 29 +2 90 8 90 90 90 89 89 90 29 +2 92 10 91 91 91 90 90 91 29 +2 93 100 432.4mm/hr Rainfall Intensity Condition (AC14) Crossfall (%) PTV 1 Temperature Correction Corrected 2 3 4 5 Average ºC Factor PTV 0 81 80 80 80 80 80 29 +2 82 2 82 82 82 81 81 82 29 +2 84 4 86 86 86 85 84 85 29 +2 87 6 88 88 87 87 87 87 29 +2 89 8 90 90 89 89 89 89 29 +2 91 10 91 91 90 90 90 90 29 +2 92 Normal Condition (AC 20) Crossfall (%) PTV Temperature Correction Corrected 1 2 3 4 5 Average ºC Factor PTV 0 88 87 87 87 87 87 30 +2 89 2 90 90 90 89 88 89 30 +2 91 4 90 90 90 90 90 90 30 +2 92 6 93 93 93 93 93 93 30 +2 95 8 96 96 96 96 95 96 30 +2 98 10 97 97 97 97 97 97 30 +2 99 101 30mm/hr Rainfall Intensity Condition (AC 20) Crossfall (%) PTV Temperature Correction Corrected 1 2 3 4 5 Average ºC Factor PTV 0 85 85 85 85 85 85 30 +2 87 2 86 86 86 86 85 86 30 +2 88 4 90 89 89 89 89 89 30 +2 91 6 93 93 93 93 93 93 30 +2 95 8 97 96 96 96 95 96 30 +2 98 10 97 97 97 96 96 97 30 +2 99 220.5mm/hr Rainfall Intensity Condition (AC 20) Crossfall (%) PTV Temperature Correction Corrected 1 2 3 4 5 Average ºC Factor PTV 0 83 83 83 83 83 83 29 +2 85 2 85 85 84 84 84 84 29 +2 86 4 87 87 87 87 86 87 29 +2 89 6 90 90 90 90 90 90 29 +2 92 8 93 93 93 92 92 93 29 +2 95 10 96 96 96 95 94 95 29 +2 97 102 432.4mm/hr Rainfall Intensity Condition (AC 20) Crossfall (%) PTV Temperature Correction Corrected 1 2 3 4 5 Average ºC Factor PTV 0 82 82 82 82 81 82 29 +2 84 2 84 83 83 83 83 83 29 +2 85 4 86 86 86 86 86 86 29 +2 88 6 90 90 90 89 89 90 29 +2 92 8 93 92 92 92 91 92 29 +2 94 10 95 94 94 93 93 94 29 +2 96 103 APPENDIX 9 ANALYSIS OF VARIANCE Effect of Rainfall Intensity on Crossfall ANOVA of Rainfall Intensity on 0% Crossfall 30 mm/hr 85 86 87 202.5mm/hr 84 84 85 432.4 mm/hr 82 82 84 SUMMARY Groups Column 1 Column 2 Column 3 Count 3 3 3 Sum 258 253 248 Average 86 84.33333333 82.66666667 Variance 1 0.333333 1.333333 ANOVA Source of Variation Between Groups Within Groups SS 16.66666667 5.333333333 df 2 6 MS 8.333333333 0.888888889 F 9.375 Total 22 8 AC10 AC14 AC20 Anova: Single Factor P-value F crit 0.014247 5.143253 104 ANOVA of Rainfall Intensity on 2% crossfall 30 mm/hr 86 87 88 202.5mm/hr 85 85 86 432.4 mm/hr 84 84 85 SUMMARY Groups Column 1 Column 2 Column 3 Count 3 3 3 Sum 261 256 253 Average 87 85.33333333 84.33333333 Variance 1 0.333333 0.333333 ANOVA Source of Variation Between Groups Within Groups SS 10.88888889 3.333333333 df 2 6 MS 5.444444444 0.555555556 F 9.8 Total 14.22222222 8 AC10 AC14 AC20 Anova: Single Factor P-value F crit 0.012875 5.143253 105 ANOVA of Rainfall Intensity on 4% crossfall AC10 AC14 AC20 30 mm/hr 87 89 91 202.5mm/hr 86 87 89 432.4 mm/hr 85 87 88 Sum Average Anova: Single Factor SUMMARY Groups Column 1 Column 2 Column 3 ANOVA Source of Variation Between Groups Within Groups Total Count 3 3 3 SS 8.666666667 17.33333333 26 267 262 260 df 2 6 8 Variance 89 4 87.33333333 2.333333 86.66666667 2.333333 MS 4.333333333 2.888888889 F P-value F crit 1.5 0.296296 5.143253 106 ANOVA of Rainfall Intensity on 6% crossfall 30 mm/hr 88 91 95 202.5mm/hr 87 90 92 432.4 mm/hr 85 89 92 SUMMARY Groups Column 1 Column 2 Column 3 Count 3 3 3 Sum 274 269 266 Average 91.33333333 89.66666667 88.66666667 Variance 12.33333 6.333333 12.33333 ANOVA Source of Variation Between Groups Within Groups SS 10.88888889 62 df 2 6 MS 5.444444444 10.33333333 F P-value F crit 0.526882 0.615448 5.143253 Total 72.88888889 8 AC10 AC14 AC20 Anova: Single Factor 107 ANOVA of Rainfall Intensity on 8% crossfall 30 mm/hr 90 93 98 202.5mm/hr 88 92 95 432.4 mm/hr 88 91 94 SUMMARY Groups Column 1 Column 2 Column 3 Count 3 3 3 Sum 281 275 273 Average 93.66666667 91.66666667 91 Variance 16.33333 12.33333 9 ANOVA Source of Variation Between Groups Within Groups SS 11.55555556 75.33333333 df 2 6 MS 5.777777778 12.55555556 F P-value F crit 0.460177 0.651732 5.143253 Total 86.88888889 8 AC10 AC14 AC20 Anova: Single Factor 108 ANOVA of Rainfall Intensity on 10% crossfall 30 mm/hr 92 94 99 202.5mm/hr 91 93 97 432.4 mm/hr 89 92 96 SUMMARY Groups Column 1 Column 2 Column 3 Count 3 3 3 Sum 285 281 277 Average 95 93.66666667 92.33333333 Variance 13 9.333333 12.33333 ANOVA Source of Variation Between Groups Within Groups SS 10.66666667 69.33333333 df 2 6 MS 5.333333333 11.55555556 F P-value F crit 0.461538 0.650963 5.143253 Total 80 8 AC10 AC14 AC20 Anova: Single Factor 109 Effect of Rainfall Intensity on Surface Type ANOVA of Rainfall Intensity on AC10 30mm/hr 202.5mm/hr 0% 85 84 2% 86 85 4% 87 86 6% 88 87 8% 90 88 10% 92 91 432.4mm/hr 82 84 85 85 88 89 Anova: Single Factor SUMMARY Groups Column 1 Column 2 Column 3 Count Sum 6 6 6 ANOVA Source of Variation Between Groups Within Groups SS 18.77777778 98.33333333 Total 117.1111111 df Average Variance 528 88 6.8 521 86.83333333 6.166667 513 85.5 6.7 MS F P-value F crit 2 9.388888889 1.432203 0.269631 3.68232 15 6.555555556 17 110 ANOVA of Rainfall Intensity on AC14 30mm/hr 202.5mm/hr 0% 86 84 2% 87 85 4% 89 87 6% 91 90 8% 93 92 10% 94 93 432.4mm/hr 82 84 87 89 91 92 Anova: Single Factor SUMMARY Groups Column 1 Column 2 Column 3 ANOVA Source of Variation Between Groups Within Groups Total Count Sum 6 6 6 SS 540 531 525 df Average Variance 90 10.4 88.5 13.9 87.5 15.5 19 199 MS 2 9.5 15 13.26666667 218 17 F P-value F crit 0.71608 0.504632 3.68232 111 ANOVA of Rainfall Intensity on AC20 30mm/hr 202.5mm/hr 0% 87 85 2% 88 86 4% 91 89 6% 95 92 8% 98 95 10% 99 97 432.4mm/hr 84 85 88 92 94 96 Anova: Single Factor SUMMARY Groups Column 1 Column 2 Column 3 ANOVA Source of Variation Between Groups Within Groups Total Count Sum 6 6 6 SS 32.33333333 368.1666667 400.5 df Average Variance 558 93 26 544 90.66666667 23.46667 539 89.83333333 24.16667 MS F P-value F crit 2 16.16666667 0.658669 0.531881 3.68232 15 24.54444444 17 112 The Effect of Crossfall on Rainfall Intensity ANOVA of Crossfall on 30mm/hr Intensity 0% 2% 4% AC10 85 86 87 AC14 86 87 89 AC20 87 88 91 6% 88 91 95 8% 90 93 98 10% 92 94 99 Anova: Single Factor SUMMARY Groups Column 1 Column 2 Column 3 Column 4 Column 5 Column 6 ANOVA Source of Variation Between Groups Within Groups Total Count 3 3 3 3 3 3 SS 196.6667 95.33333 292 Sum Average Variance 258 86 1 261 87 1 267 89 4 274 91.33333 12.33333 281 93.66667 16.33333 285 95 13 df MS F P-value F crit 5 39.33333 4.951049 0.010865 3.105875 12 7.944444 17 113 ANOVA of Crossfall on 202.5mm/hr Intensity 0% 2% AC10 84 85 AC14 84 85 AC20 85 86 4% 86 87 89 6% 87 90 92 Average 84.33333 85.33333 87.33333 89.66667 91.66667 93.66667 Variance 0.333333 0.333333 2.333333 6.333333 12.33333 9.333333 8% 88 92 95 10% 91 93 97 Anova: Single Factor SUMMARY Groups Column 1 Column 2 Column 3 Column 4 Column 5 Column 6 ANOVA Source of Variation Between Groups Within Groups Total Count 3 3 3 3 3 3 SS 200 62 262 Sum 253 256 262 269 275 281 df MS F P-value F crit 5 40 7.741935 0.001834 3.105875 12 5.166667 17 114 ANOVA of Crossfall on 432.4mm/hr Intensity 0% 2% AC10 82 84 AC14 82 84 AC20 84 85 4% 85 87 88 6% 85 89 92 Average 82.66667 84.33333 86.66667 88.66667 91 92.33333 Variance 1.333333 0.333333 2.333333 12.33333 9 12.33333 8% 88 91 94 10% 89 92 96 Anova: Single Factor SUMMARY Groups Column 1 Column 2 Column 3 Column 4 Column 5 Column 6 Count 3 3 3 3 3 3 ANOVA Source of Variation Between Groups Within Groups SS 212.9444 75.33333 Total 288.2778 Sum 248 253 260 266 273 277 df MS F P-value F crit 5 42.58889 6.784071 0.003194 3.105875 12 6.277778 17 115 The Effect of Crossfall on Surface Type ANOVA of Crossfall on AC10 0% None 87 30mm/hr 85 202.5mm/hr 84 432.4mm/hr 82 2% 88 86 85 84 4% 89 87 86 85 6% 91 88 87 85 Sum 338 343 347 351 358 365 Average 84.5 85.75 86.75 87.75 89.5 91.25 Variance 4.333333 2.916667 2.916667 6.25 3.666667 2.916667 8% 92 90 88 88 10% 93 92 91 89 Anova: Single Factor SUMMARY Groups Column 1 Column 2 Column 3 Column 4 Column 5 Column 6 Count 4 4 4 4 4 4 ANOVA Source of Variation Between Groups Within Groups SS 122.8333 69 df MS F P-value F crit 5 24.56667 6.408696 0.001384 2.772853 18 3.833333 Total 191.8333 23 116 ANOVA of Crossfall on AC14 None 30mm/hr 202.5mm/hr 432.4mm/hr 0% 87 86 84 82 2% 89 87 85 84 4% 90 89 87 87 6% 92 91 90 89 Sum 339 345 353 362 369 373 Average 84.75 86.25 88.25 90.5 92.25 93.25 Variance 4.916667 4.916667 2.25 1.666667 0.916667 0.916667 8% 93 93 92 91 10% 94 94 93 92 Anova: Single Factor SUMMARY Groups Column 1 Column 2 Column 3 Column 4 Column 5 Column 6 Count 4 4 4 4 4 4 ANOVA Source of Variation Between Groups Within Groups SS 227.2083 46.75 df MS F P-value F crit 5 45.44167 17.49626 2.36E-06 2.772853 18 2.597222 Total 273.9583 23 117 ANOVA of Crossfall on AC20 0% None 89 30mm/hr 87 202.5mm/hr 85 432.4mm/hr 84 2% 91 88 86 85 4% 92 91 89 88 6% 95 95 92 92 8% 98 98 95 94 10% 99 99 97 96 Anova: Single Factor SUMMARY Groups Column 1 Column 2 Column 3 Column 4 Column 5 Column 6 Count 4 4 4 4 4 4 Sum 345 350 360 374 385 391 ANOVA Source of Variation Between Groups Within Groups SS 442.375 74.25 df 5 18 Total 516.625 23 Average Variance 86.25 4.916667 87.5 7 90 3.333333 93.5 3 96.25 4.25 97.75 2.25 MS F P-value F crit 88.475 21.44848 5.24E-07 2.772853 4.125 118 The effect of Surface Type on Rainfall Intensity ANOVA of Surface Type on 30mm/hr Intensity AC10 AC14 AC20 0% 85 86 87 2% 86 87 88 4% 87 89 91 6% 88 91 95 8% 90 93 98 10% 92 94 99 Anova: Single Factor SUMMARY Groups Column 1 Column 2 Column 3 ANOVA Source of Variation Between Groups Within Groups Total Count 6 6 6 SS Sum 528 540 558 df Average Variance 88 6.8 90 10.4 93 26 MS 76 216 2 15 292 17 F P-value F crit 38 2.638889 0.104239 3.68232 14.4 119 ANOVA of Surface Type on 202.5mm/hr Intensity AC10 AC14 AC20 0% 84 84 85 2% 85 85 86 4% 86 87 89 6% 87 90 92 8% 88 92 95 10% 91 93 97 Anova: Single Factor SUMMARY Groups Column 1 Column 2 Column 3 ANOVA Source of Variation Between Groups Within Groups Total Count 6 6 6 SS 44.33333333 217.6666667 262 Sum Average Variance 521 86.83333333 6.166667 531 88.5 13.9 544 90.66666667 23.46667 df MS F P-value F crit 2 22.16666667 1.527565 0.248989 3.68232 15 14.51111111 17 120 ANOVA of Surface Type on 432.4mm/hr Intensity AC10 AC14 AC20 0% 82 82 84 2% 84 84 85 4% 85 87 88 6% 85 89 92 8% 88 91 94 10% 89 92 96 Anova: Single Factor SUMMARY Groups Column 1 Column 2 Column 3 Count 6 6 6 ANOVA Source of Variation Between Groups Within Groups SS 56.44444444 231.8333333 Total 288.2777778 Sum Average Variance 513 85.5 6.7 525 87.5 15.5 539 89.83333333 24.16667 df MS F 2 28.22222222 1.826024 15 15.45555556 17 P-value F crit 0.19509 3.68232 121 Effect of Surface Type on Crossfall ANOVA of Surface Type on 0% Crossfall 30mm/hr 202.5mm/hr 432.4mm/hr AC10 85 84 82 AC14 86 84 82 AC20 87 85 84 Anova: Single Factor SUMMARY Groups Column 1 Column 2 Column 3 Count 3 3 3 Sum 251 252 256 ANOVA Source of Variation Between Groups Within Groups SS 4.666667 17.33333 df 2 6 Total 22 8 Average Variance 83.66667 2.333333 84 4 85.33333 2.333333 MS F P-value F crit 2.333333 0.807692 0.489078 5.143253 2.888889 122 ANOVA of Surface Type on 2% Crossfall AC10 86 85 84 30mm/hr 202.5mm/hr 432.4mm/hr AC14 87 85 84 AC20 88 86 85 Anova: Single Factor SUMMARY Groups Column 1 Column 2 Column 3 Count 3 3 3 ANOVA Source of Variation Between Groups Within Groups SS 2.888889 11.33333 Total 14.22222 Sum Average Variance 255 85 1 256 85.33333 2.333333 259 86.33333 2.333333 df MS F P-value F crit 2 1.444444 0.764706 0.506023 5.143253 6 1.888889 8 123 ANOVA of Surface Type on 4% Crossfall AC10 87 86 85 30mm/hr 202.5mm/hr 432.4mm/hr AC14 89 87 87 AC20 91 89 88 Anova: Single Factor SUMMARY Groups Column 1 Column 2 Column 3 ANOVA Source of Variation Between Groups Within Groups Total Count 3 3 3 SS 16.66667 9.333333 26 Sum Average Variance 258 86 1 263 87.66667 1.333333 268 89.33333 2.333333 df MS F P-value F crit 2 8.333333 5.357143 0.046258 5.143253 6 1.555556 8 124 ANOVA of Surface Type on 6% Crossfall 30mm/hr 202.5mm/hr 432.4mm/hr AC10 88 87 85 AC14 91 90 89 AC20 95 92 92 Anova: Single Factor SUMMARY Groups Column 1 Column 2 Column 3 Count 3 3 3 Sum 260 270 279 ANOVA Source of Variation Between Groups Within Groups SS 60.22222 12.66667 df 2 6 Total 72.88889 8 Average Variance 86.66667 2.333333 90 1 93 3 MS F P-value F crit 30.11111 14.26316 0.005248 5.143253 2.111111 125 ANOVA of Surface Type on 8% Crossfall 30mm/hr 202.5mm/hr 432.4mm/hr AC10 90 88 88 AC14 93 92 91 AC20 98 95 94 Anova: Single Factor SUMMARY Groups Column 1 Column 2 Column 3 Count 3 3 3 Sum 266 276 287 ANOVA Source of Variation Between Groups Within Groups SS 73.55556 13.33333 df 2 6 Total 86.88889 8 Average Variance 88.66667 1.333333 92 1 95.66667 4.333333 MS 36.77778 2.222222 F 16.55 P-value F crit 0.003613 5.143253 126 ANOVA of Surface Type on 10% Crossfall 30mm/hr 202.5mm/hr 432.4mm/hr AC10 92 91 89 AC14 94 93 92 AC20 99 97 96 Anova: Single Factor SUMMARY Groups Column 1 Column 2 Column 3 Count 3 3 3 Sum 272 279 292 ANOVA Source of Variation Between Groups Within Groups SS 68.66667 11.33333 df 2 6 Total 80 8 Average Variance 90.66667 2.333333 93 1 97.33333 2.333333 MS F P-value F crit 34.33333 18.17647 0.002843 5.143253 1.888889 127 APPENDIX 10 Penetration Test Sand Patch Test Pendulum Calibration Polished Stone Value Test Rainfall Simulator Sample Coring