CONSTRUCTION
MATERIALS AND
TESTING LABORATORY
MANUAL
CIVIL ENGINEERING DEPARTMENT
CARLOS HILADO MEMORIAL STATE COLLEGE- TALISAY
TABLE OF CONTENTS
Preface
General Laboratory Instructions
General Instruction for Laboratory Report
Experiment No.1
Reducing Field Sample of Aggregate .
Experiment No. 2
Sieve Analysis of Coarse and Fine Aggregates .
Experiment No. 3
Determination of Specific Gravity and Water Absorption of Aggregates . 14
Experiment No. 4
Determination of Density of Aggregates .
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Experiment No. 5
Determination of Moisture Content of Aggregates .
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Experiment No. 6
Making and Curing of Concrete Test Specimens
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25
Experiment No. 7
Determination of Compressive Strength of Cylindrical
Concrete Specimen .
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Experiment No. 8
Determination of Setting Time of Hydraulic Cement
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Experiment No. 9
Determination of Penetration of Bituminous Materials .
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Experiment No. 10 Determination of Modulus of Rupture of Concrete Beam .
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Experiment No. 11 Determination of Tensile Strength of Concrete Cylinder .
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Experiment No. 12 Determination of Static Bending of Wood .
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Experiment No. 13 Determination of Compressive Strength of Wood Parallel to Grain . . 45
Experiment No. 14 Determination of Shear Stress of Wood Parallel to Grain .
Experiment No. 15 Determination of Moisture Content of Wood .
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Experiment No. 16 Determination of Compressive Strength of Concrete Hollow
Blocks .
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Experiment No. 17 Los Angeles Abrasion Test . .
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Experiment No. 18 Marshall Test of Asphalt .
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Experiment No. 19 Tensile Test of Steel Bars .
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GENERAL LABORATORY INSTRUCTIONS
LABORATORY MANUALS
This manual has been prepared to present the standardized test procedures for checking
materials in conformance with the American Society for Testing and Materials. This manual
describes the test procedures that are currently in use in the Construction Materials and Testing
Laboratory. Please read the appropriate materials in the laboratory manuals carefully before
attending the laboratory. Data sheets are in the appendix of this document or will be provided
during laboratory class.
OBJECTIVE
The objective of this manual is to acquaint the student with some physical and
mechanical properties of selected construction materials and standard methods to be used to
evaluate these properties. A secondary objective is to develop the student’s proficiency in
preparing an engineering report. The report is to resemble professional engineering reports as
much as possible. Grammar, efficient communication and result will weigh heavily in the final
grade.
FIELD TRIPS
Field trips are considered as an inspection visit. The observations of the field trip will be
included in the appendix of the report. They should observe the general operation, quality
control, and other factors that may affect the facility’s ability to meet the requirements of the
construction contract.
THE REPORT
All reports are to be written in the third person; for example, “the test was conducted,”
not “we conducted the test.” Each student is expected to come up with fictitious company name
and logo. Reports are to apply to the hypothetical project scenario given in this manual. Report
must be typed (excluding raw data sheets), and all figures and tables must be computer
generated unless otherwise stated. Bind the material neatly. NO BULKY NOTEBOOKS! Points will
be deducted for multiple and sloppy stapling. You are encouraged to work together in preparing
the reports. However, the report must be your individual effort. If the grader discover identical
charts, tables, and discussion between reports he/she can only assume someone did not do their
own work. Reproducing reports from past electronic files is prohibited. In other words, zeros will
be assigned to reports that give any indication of being duplicated or copied from previous lab
reports or another team’s report.
LABORATORY TEST
3|Page
The Construction Materials and Testing course provides credit for three hours of lecture
and three hours of laboratory work per week. The laboratory testing has been arranged so that
each test may be performed well within the three-hour period.
Each laboratory will consist of three parts. These are:
I. A short briefing on the test which is to be performed.
II. The actual laboratory testing. This will be done in groups of three or four students. In some
cases, this may be a demonstration by the instructor.
III. The reduction of rough data. Once the testing is complete each group has secured its own
data, the data will be reduced and all necessary computations will be made. Each student will
secure a copy of all data and calculations before leaving the laboratory room.
In general, the laboratory report will be submitted one week after each laboratory is
performed. General notes on the laboratory reports are given on the following page. Specific
instruction will be given for each test.
Most of the experiments require some preparation that must be done before coming to
class. Completing this reading and/or calculation will prevent needless delay, mistakes, and
wasted effort during laboratory period.
During the laboratory period reasonable care should be exercised to prevent damage to
equipment and personnel. The equipment in the laboratory is for your use and most of it is quite
rugged and not easily damaged; however, if in doubt concerning the operation of the
equipment, ask the instructor.
An essential element of good laboratory practice is maintaining a clean and orderly
laboratory. It will be the responsibility of each group to clean its own equipment and area where
their laboratory work is performed. All equipment will be returned to its proper place. One
group will be responsible each week for the over-all clean up. The clean-up group will see to it
that all equipment is in its proper place. This group will check out with instructor each week.
Some of the test will require that someone will check on the test on the day following the
laboratory period. The group may delegate one person to do this. However, each group will be
responsible for securing any data obtained.
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GENERAL INSTRUCTION FOR LABORATORY REPORT
The report is to be written in the style of a professional engineering report such as to be
submitted by a material-testing laboratory to a construction company or an engineering firm.
The report should look like an engineering documents. It is recommended that they ne neatly
typed.
The instructor and this manual will provide specific instructions for laboratory reports for
each test. The following are the components of formal report:
1. The Title Page/Cover Page: The first page of the report is the title page or a cover page. This
page identifies the test to be performed. It shows course number
and the laboratory section number, name of person submitting
the report, party number, name of persons in your party, and date
of submission (date actually submitted, not the date due).
2. Table of Contents:
The table of contents is used to facilitate the grading of the
reports, and will be used to record the points awarded for each
category. The table of contents should include page numbers and
the report pages should include computer generated page
numbers. Chart and table titles and numbers should also show in
the table of contents.
3. Introduction:
Brief statement as to what you are attempting to accomplish by
performing the test. State significance (usefulness) of the test.
4. Procedure:
This section identify materials, specimen, testing apparatus, and
testing procedure.
5. Test Results:
This section will contain those facts or answer that you obtained in
your experiment, either direct measurements or calculations
based on measurements. The section should also include some
text referring to tables and charts. This section may also include a
brief statement of the method and materials used to obtain the
results. The appropriate standard or test method should be cited
on this section. Each table or graph should be self-explanatory – to
include suitable title, use a legend or data points and curves.
6. Discussion of Results:
In this section the writer provides the foundation upon which his/
her conclusion will rest. This acceptance or rejection of the
conclusion by the reader will depend largely on discussion of
results. Under this heading the writer will comment upon the
validity of the results and make comparison with typical values for
the measurement parameters. Remember “the acceptance and
5|Page
rejection of the conclusions drawn in the report is directly related
to the skill of the reporter in providing an accurate and convincing
discussion of the reasoning upon which the conclusions are
based.” Give reasons for discrepancies if serious difference
appears to exist. Mention limitation of test.
7. Conclusion and Recommendations: Brief statement presenting a personal analysis of the
results. Conclusions must be reported by, but do not include, the
actual results. Statement about the reasonableness of results
should be included. Apply conclusions and recommendations to
the fictitious objective given at the beginning of each experiment
or to a project scenario created by the student.
8. Appendices:
This section includes laboratory data, calculation and data sheets.
Raw Data and Additional Information
Inspection: This section should describe the findings of the inspection visit and the comment on
the company’s quality control and ability to meet the specifications and
requirements of the contract.
Data Form: Include the raw data recorded on the forms during the laboratory test. Your
laboratory data usually be taken on the forms provided. Do not erase errors. Line
them out. It is neither necessary nor desirable to copy data on to clean data sheets
for the sake of neatness, since the important results have been provided in the test
result section. Also include computer spreadsheets of other information that should
not be in the body of the report.
References: Include a list of all references used, including any software (excluding word
processing or spreadsheets). Include consolation with the Laboratory Consultants,
Instructor, or Professor. Make sure each reference is complete. The reference
section of this document should be used as a guide. If the reference to a page
numbers, include this information. If you referred to a laboratory report prepared in
previous term by another student, this should be the referenced as well. Reference
to a previous laboratory report is acceptable. However, plagiarism and other
inappropriate uses of these old report will be considered a violation of the Honor
of Conduct.
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Experiment No. 1: Reducing Field Sample of Aggregate
Discussion:
These methods cover the reduction of field samples to testing size employing techniques
that are intended to minimize variation in measured characteristics between the test samples
selected and the field sample.
Specifications for aggregate require sampling portion of the material for testing. Other
factors being equal, larger samples will tend to be more representative of the total supply.
These methods provide for reducing the large sample obtained in the field to a
convenient size. This is for the purpose of conducting a number of tests to describe the material
and measure its quality in manner that the smaller portion is most likely to be a representation
of the field sample, and thus the total supply. The individual test methods provide for minimum
weights of material to be tested.
Objective: To learn and understand the correct method of obtaining sample aggregate for
mechanical analysis.
Referenced Documents: ASTM (C 702-98, C 33, D 75, C 330 -89)
AASHTO T 248
Selection of Method:
1. Fine Aggregate – Filed sample of fine aggregate that are drier than the saturated-surface-dry
condition shall be reduced in size by a mechanical splitter according to Method A. Field sample
having free moisture on the particle surface may be reduced in sizes by quartering method
according to Method B.
1.1 If the use of Method B is desired, and the field sample does not have free moisture on
the particle surfaces, the sample may be moistened to achieve this condition, thoroughly
mixed, and then the sample reduction performed.
1.2 If the use of Method A is desired and the field sample has free moisture on the
particle surfaces, the entire field sample may be dried to at least surface-dry condition
using the temperature that do not exceed those specified for any of the test
contemplate, and then the sample reduction performed.
2. Coarse Aggregates and Mixture of Coarse and Fine Aggregates – Reduce the sample using a
mechanical splitter in accordance with Method A (preferred method) or by a quartering method
in accordance with Method B.
Apparatus and Materials:
1. Representative sample of aggregate
2. Spade
3. Container
4. Sample Splitter
7|Page
Method A – Mechanical Splitter
Procedure:
1. Check moisture content of aggregate. If the sample has free moisture on the particle
surface the entire sample must be dried to at least the SSD condition prior to reduction
by splitter.
2. Check sample splitter chute opening. (Their number and width relative to maximum size
of aggregate).
3. Place the sample in the hopper or pan and uniformly distribute it from edge to edge, so
that when it is introduced into the chutes, approximate and equal amounts will flow
through each chutes.
4. The rate at which the sample is introduced shall be of such as to allow free flowing
through the chutes into the receptacle below.
5. Reintroduce the portion of the sample in one of the receptacles as many times as
necessary to reduce to specified size for the intended test.
6. The portion of the material collected in the other receptacle may be reserved for
reduction size in size for other test.
Method B – Quartering
1. Place the sample on a hard, clean, level surface where there will neither loss of material
nor the accidental addition of foreign material.
2. Mix the material thoroughly by turning the entire sample over three times. With the last
turning, shovel the entire sample into a conical pile by depositing each shovel on top of
the preceding one.
3. Carefully flatten the conical pile to a uniform thickness and diameter, by pressing down
the apex with a shovel or other device so that each quarter sector of the resulting pile
will contain the material originally in it. The diameter should be approximately four to
eight times the thickness.
4. Divide the flattened mass approximately into four equal part quarters with a shovel,
trowel or other suitable device and remove to diagonally oppose quarters, including all
fine materials, and brush the cleared spaces clean.
5. Successively mix and quarter the remaining material until the sample is reduced to the
desired size.
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Experiment No. 2: Sieve Analysis of Coarse and Fine Aggregate
Discussion:
The sieve analysis is used to determine the particle size distribution of gradation of an
aggregate. A suitable gradation of an aggregate in a concrete mix is desirable in order to secure
workability of concrete mix and economy in the use of cement. For asphalt concrete, suitable
gradation will not only affect the workability of the mixture and economy in the use of asphalt,
but will affect significantly the strength and other important properties.
The sieve analysis of an aggregate is performed by “sifting” the aggregate through a
series of sieves nested in order, with smallest opening at the bottom. These sieves have square
openings and are usually constructed with wire mesh. In the testing of concrete aggregates,
there is generally employed a series of sieves in which any sieve in the series has twice the clear
opening of the next smaller size in the series. The U.S. Standard Sieve Series and the clear
opening of the sieve are given below.
U.S. Standard Sieve Size
No. 100
No. 50
No. 30
No. 16
No. 8
No. 4
3/8 “
½” (half size)
¾”
1 in. ( half size)
1 ½ in.
Clear Opening (in.)
0.0059
0.0117
0.0232
0.0469
0.0937
0.187
0.375
0.500
0.750
1.000
1.500
Sometimes closer sizing than is given by the standard series is desired, in which case
“half” size or “odd” sizes are employed; the ½ in and 1 in. shown are half sizes.
Coarse aggregate is usually considered to be larger and fine aggregates smaller
than #4 sieve. Thus all sieves need not to be used physically in the nest but are still considered in
the analysis. For example, sieve larger than 3/8 in is not used for the sand and sieve smaller than
No. 8 are seldom used for gravel.
The fineness modulus is an index number, which is roughly proportional to the average
size of the particles in a given aggregate. It is computed by adding the cumulative percentage
coarser than each of certain sieves and dividing by 100. (Note: Even though some material may
be retained on the pan, it is not considered a sieve and does not enter into computations for
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fineness modulus. In addition, if sieves other than those standard sieves listed above are used,
they are not used directly in the computations and any material retained on such sieves should
be considered as being retained on the next smaller sieve of the series used in the computations,
e.g. any material retained on a 1 in sieve would be added to the ¾ in. sieve for purposes of
fineness modulus computation. However, the amount and percentage of the 1 in. material
would appear in the tabular listing in the sieve analysis).
The following illustrate the calculations of the fineness modulus:
Sieve No.
Weight Retained
4
8
10
16
30
50
80
100
Pan
30
40
30
30
35
45
40
50
10
Fineness Modulus of Sand =
Cumulative Weight
Retained
30
70
100
130
165
210
250
300
310
% Cumulative
Retained
9.7
22.6
-42.0
53.3
67.8
-96.8
100
9.7 + 22.6 + 42.0 + 53.3 + 67.8 +96.8 = 2.92
100
“Odd “sieves not used directly in fineness modulus calculations.
An interpretation of the fineness modulus might be that it represents the (weighted) average of
the group upon which the material is retained, No. 100 being the first, No. 50 second, etc. Thus
for the sand with FM of 3.00, sieve No. 30 (the third sieve) would be the average sieve size upon
which the aggregate is retained.
Objective: To determine the particle size distribution of fine and coarse aggregate by sieving.
Referenced Documents: ASTM (136-96a, C 702, E 11, D 75)
AASHTO (T 27-91, T 11-65)
Apparatus:
Balance, accurate to 0.1 g
Set of sieves with pan and cover
Mechanical sieve shaker (optional)
Brush
Oven
10 | P a g e
Procedure:
1) Obtain a representative sample by quartering or by the use of sample splitter. The sample to
be tested should be the approximate weight desired when dry. For this experiment about
500 grams of fine aggregate and about 10 to 12 kilograms of coarse aggregate.
2) Dry the samples to constant temperature in the oven at a temperature 110 ± 5°C (230 ±
41°F).
3) Assemble the sieves in order of decreasing size of opening from top to bottom and place
sample on top of the sieve and cover it with the lid.
(a) for coarse aggregate: 1”, ¾ “, ½”, 3/8”, #4 , #8, pan
(b) for fine aggregate: 3/8”, #4 , #8, #30, #50, #100, pan
4) Agitate the sieve by hand or by mechanical shaker for five minutes or for a sufficient
period.
5) Limit the quantity of material on a given sieve so that all the particles have opportunity to
reach sieve openings a number of times during the sieving operations. For the sieve with
openings smaller than No. 4 (4.75mm), the weight retained on any sieve at the completion of
the sieving operations shall not exceed 6 kg/m2 of sieving surface. For the sieve with
openings No. 4 (4.75mm) and larger, the weight in kg/m2 of the sieving surface shall not
exceed the product of 2.5 x (sieve opening in mm). In no case shall the weight be so great as
to cause a permanent deformation of the sieve cloth.
6) Continue sieving for sufficient period in such a manner that, after completion, not more that
0.5 percent by weight of the total sample passes any sieve during one (1) minute of
continuous hand sieving.
7) Weigh the material that is retained on each sieves, including the weight retained in the pan
and record in the data sheet. The total weight of the material after sieving should check
closely with original sample placed on the sieve. If the sum of these weights is not within 1
percent (0.3 for ASTM requirement) of the original sample, the procedure should be
repeated.
8) Compute the cumulative percent retained on and the percent passing each sieve.
9) Plot the gradation curves for the coarse and the fine aggregate from the experiment on the
graph provided. Plot the specific gradation curves for coarse and fine aggregates (to be
specified by the laboratory instructor). Plot the combine-grading curve using the 40%
aggregate and 60% fine aggregate.
10) Compute the Fineness Modulus for fine and coarse aggregates.
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CONSTRUCTION MATERIALS AND TESTING LABORATORY
CIVIL ENGINEERING DEPARTMENT
CARLOS HILADO MEMORIAL STATE COLLEGE-TALISAY
SIEVE ANALYSIS DATA SHEET
Name:
Group No.:
COARSE AGGREGATE
Initial Weight:
Sieve
No.
Weight
Retained (kg)
Cum. Weight
Retained (kg)
Cum. Percent
Retained (%)
Percent
Passing (%)
Cum. Percent
Retained (%)
Percent
Passing (%)
FINE AGGREGATE
Initial Weight:
Sieve
No.
Weight
Retained (kg)
Cum. Weight
Retained (kg)
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CONSTRUCTION MATERIALS AND TESTING LABORATORY
CIVIL ENGINEERING DEPARTMENT
CARLOS HILADO MEMORIAL STATE COLLEGE-TALISAY
SIEVE ANALYSIS
Name:
Date:
Group No.:
Section:
100
P
E
R
C
E
N
T
90
80
70
60
P 50
A
S 40
S
I 30
N
G 20
10
220
210
100
50
30
10
8
4
3/8”
¾”
SIEVE SIZE
13 | P a g e
1”
Experiment 3: Determination of Specific Gravity and Water Absorption of
Aggregates
Discussion:
Basically, specific gravity is the ratio of the weight of a given volume of material to the
weight of an equal volume of water. However, there are several variations on this definition
depending upon the material and purposes for which the value of specific gravity are to be used.
In concrete work, the term specific gravity customarily refers to the density of the individual
particles, not to the aggregated mass as a whole. The most commons definition of the specific
gravity in concrete aggregate in saturated surface-dry condition (SSD). The bulk (oven-dry)
specific gravity are used to a lesser degree. Solid unit weight in pounds per cubic foot (pcf) of an
aggregate is customarily defined as the specific gravity times 62.4 pcf.
The absorption capacity is determined by finding the weight of an aggregate under SSD
condition and oven-dry condition. The difference in weights expressed as a percentage of the
oven-dry sample weight is the absorption capacity. Coarse aggregate are considered to be
saturated surface-dry when they have wiped free of visible moisture films with a cloth after the
aggregates have been soaked in a water for a long period of time (over 24 hours). The saturateddry condition of fine aggregate is usually taken as that at which a previously wet sample just
become free flowing.
Objective: The test method covers the determination of the specific gravity and absorption of
coarse and fine aggregate.
Referenced Documents: ASTM (C 127, C 136, C 70, C 702)
Apparatus:
For Coarse Aggregate
1)
2)
3)
4)
5)
Balance, sensitive to 0.01lb or gram
Wire mesh basket
Drying Oven
3/8” Sieve
Water tank
For Fine Aggregate
1)
2)
3)
4)
Balance, sensitive to 0.01lb or gram
500 ml Chapman Flask
Dryer
Drying Oven
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Preparation of Sample (for Coarse Aggregate)
1) Thoroughly mixed the sample aggregate and reduce it to the approximate quantity needed
using quartering or mechanical shaker method.
2) Reject all materials passing 4.75 mm (No. 4) sieve sieving and thoroughly washing to remove
dust or other coatings from the surface.
3) The minimum weight of test sample to be used is given below:
Nominal Maximum Size, mm (in.)
12.5 (1/2) or less
19.0 (3/4)
25.0(1)
37.5(1 ½)
50 (2)
63(2 ½)
75(3)
90 (3 ½)
100 (4)
112(4 ½)
125 (5)
150 (6)
Maximum Weight of Test Sample kg, (lb.)
2(4.4)
3(6.6)
4(8.8)
5(11)
8(18)
12(26)
18(40)
25(55)
40(22)
50(110)
75(165)
125(276)
Procedure:
For Coarse Aggregate
1) Dry the test sample to constant weight at a temperature of 110±5°C (230±9°F).
2) Cool in air at room temperature 1 to 3 hours, or until the aggregate has cooled to a
temperature that is comfortable to handle (approximately 50°C) and weigh.
3) Soak aggregate under water for 24 ± 4hours.
4) Obtain approximately 5kg of saturated coarse aggregate (retained on 3/8” sieve preferably).
5) Towel the aggregate to a saturated surface-dry condition (SSD). A moving steam may be used
to assist drying operation. Take care to avoid evaporation of water from aggregate pores
during the surface-drying operation.
6) Measure SSD weight (B) of aggregate in air to the nearest 1 gm. Do this quickly to prevent
evaporation.
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7) Place the sample in the wire mesh basket, and determine its weight in water (C) at 23 ± 1.7°C
(73.4 ± 3°F). Take care to remove all entrapped air before weighing by shaking the container
while immersed. Be sure to subtract the submerged weight of the basket from the total.
8) Place the wet aggregate in oven, and dry to constant weight at a temperature of 110 ± 5°C
(230 ± 9°F) (leave the aggregate in oven overnight). Cool the aggregate in air at room
temperature 1 to 3 hours, or until the aggregate has cooled to a temperature that is
comfortable to handle (approximately 50°C) and weigh (A).
9) From the above data (i.e., A, B, and C) calculate the three types of specific gravity and
absorption as defined below:
A
BC
B
(2) Bulk Specific Gravity (SSD) =
B C
A
(3) Apparent Specific Gravity =
AC
BA
(4) Absorption =
 100
A
(1) Bulk Specific Gravity (Dry) =
A = weight of oven-dry test sample, gm
B = weight of saturated surface-dry sample in air, gm
C = weight of test sample in water, gm
Procedure for Fine Aggregate:
1) Obtain approximately 4 kg air-dry fine aggregate (all groups working together).
2) Bring fine aggregate to SSD condition as explained by the instructor.
3) Each group takes approximately 500 gm of the SSD aggregate. Record exact weight of SSD
sample (D).
4) Fill Chapman Flask to 450 ml mark and record weight of water and flask in grams (B). The
water temperature should be about 23 ± 1.5°C (73 ± 3°F).
5) Empty the water in flask to about 200 ml marks and adds SSD aggregate to flask. Fill flask to
almost 450 ml mark with additional water.
6) “Roll” flask on flat surface to eliminate air bubbles. Then fill the flask with water up to 450
ml. Record total weight (in gm) of flask plus the water plus aggregate (C).
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7) Pour entire contents of flask into pan and place in an oven. Additional tap water may be used
as necessary to wash all aggregate out of the flask. Return after 24 hours or as long as it
takes for the aggregate to dry and record weight of oven-dry aggregates (A).
8) From the data above, calculate specific gravities and absorption defined below:
A
B  AC
A
 Bulk Specific Gravity =
B  D C
D
 Bulk Specific Gravity (SSD) =
B  D C
D A
100%
 Absorption =
A

Apparent Specific Gravity =
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CONSTRUCTION MATERIALS AND TESTING LABORATORY
CIVIL ENGINEERING DEPARTMENT
CARLOS HILADO MEMORIAL STATE COLLEGE-TALISAY
SPECIFIC GRAVITY AND WATER ABSORPTION
DATA SHEET
Name: _________________________
Date: __________________________
Group No. ___________
FINE AGGREGATE
ITEM
SSD Weight in Air (D)
Weight of Pyc. + Water (B)
Weight of Pyc. + Water + Sample (C_
Oven Dry Weight (A)
WEIGHT
COARSE AGGREGATE
ITEM
SSD Weight in Air (B)
Weight in Water (C)
Oven Dry Weight (A)
WEIGHT
RESULTS
ITEM
Apparent Specific Gravity
Bulk Specific Gravity (Dry)
Bulk Specific Gravity (SSD)
Absorption
COARSE
FINE
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Experiment 4: Determination of Density of Aggregates
Discussion:
This test covers the determination of bulk density (unit weight) of aggregate in a
compacted or loose condition, calculated voids between particles in fine coarse, or mixed
aggregates based on the same determination.
Unit weight or bulk density is the weight of a given volume of material. Basically, unit
weight is measured by filling a container of known volume with a material and weighing it. The
degree of moisture and compaction will affect the unit weight. Therefore, the ASTM has set
standard oven-dry moisture content and rodding method or compaction. The maximum unit
weight of a blend of two aggregates is about 40% fine aggregate by weight. Therefore, this is the
most economical concrete aggregate since it will require the least amount of cement.
The bulk density of aggregate is a mass of a unit volume of bulk aggregate material, in
which the volume includes the volume of the individual particle and the volume of voids
between the particles and is expressed in lb. /ft3 (kg/m3). Unit weight, is a weight (mass) per unit
volume.
Objectives: To determine the unit weight (bulk density) values that is necessary for use for
several methods of selecting proportions for concrete mixtures.
Referenced Documents: ASTM (C29, C 29M-97, C 127, C 136, C 702)
AASHTO T 11
Apparatus:
1) Balance, sensitive to 0.1lb or 0.05 kg.
2) Tamping rod, 5/8” (16.0 mm dia.), and 18” (600 mm) long.
3) Volume measure
Procedures:
1) Obtain a representative sample of air-dry thoroughly mixed coarse aggregate and reduce the
sample by quartering method.
2) Fill the measure one-third full and level the surface with fingers.
3) Rod or tamp the layer 25 strokes of the tamping rod evenly distributed over the surface.
4) Fill the measure to two-thirds full and rod 25 times without penetrating the previous layer.
5) Fill the measure to overflowing and 25 times. Level the surface with fingers or the rod such
that any slight projections of larger pieces of aggregate approximately balance the larger
voids in the surface below the top of the measure. Do not compress the aggregate.
19 | P a g e
6) Determine the weight (or mass) to the nearest 0.1 lb. (0.05kg.).
7) Calculate the unit weight.
20 | P a g e
CONSTRUCTION MATERIALS AND TESTING LABORATORY
CIVIL ENGINEERING DEPARTMENT
CARLOS HILADO MEMORIAL STATE COLLEGE-TALISAY
DENSITY OF AGGREGATES
DATA SHEET
Name: _________________________
Date: __________________________
Group No. ___________
Aggregate Size:
Maximum Size:
Nominal Grad:
Source:
ITEM
Total Weight, lb (kg.)
Measured Weight, lb. (kg.)
Weight of Aggregate, lb. (kg.)
Measure Volume, ft3(m3)
Unit Weight, lb/ft3 (kg/m3)
%Difference from Average
Trail 2
Trail 2
Trail 2
Trail 2
Calculation:
UW 
Wt  Wm
V
UW = Unit Weight (Bulk Density), lb.ft3 (kg/m3)
Wt = Weight of aggregate plus measure
Wm = Weight of calibrated measure
V = Volume
21 | P a g e
TABLE 1
DIMENSIONS OF MEASURE (U.S. CUSTOMARY SYSTEM)
Capacity
(ft3)
1/10
1/3
½
1
Inside
Diameter
(in.)
6.0 ± 0.1
8.0 ± 0.1
10.0 ± 0.1
14.0 ± 0.1
Inside Height
(in.)
6.1 ±0.1
11.5 ± 0.1
11.0 ± 0.1
11.2 ± 0.1
Minimum Thickness of Metal
(in.)
Bottom
0.20
0.20
0.20
0.20
Wall
0.10
0.10
0.12
0.12
Nominal Size
of Aggregate
(in.)
½
1
1½
½
TABLE 2
DIMENSIONS OF MEASURE (METRIC SYSTEM)
Capacity
(m3)
Inside
Diameter
(mm.)
Inside Height
(mm.)
3
10
15
30
155 ± 2
205 ± 2
255 ± 2
355 ± 2
160 ±2
205 ±2
295 ± 2
305± 2
Minimum Thickness of Metal
(in.)
Bottom
5.0
5.0
5.0
5.0
Wall
2.5
2.5
3.0
3.0
Nominal Size
of Aggregate
(mm.)
12.5
25.0
37.5
100.0
TABLE 3
UNIT WEIGHT OF WATER
Temperature
°F
60
65
70
(73.4)
75
80
85
°C
15.6
18.3
21.1
(23.0)
23.9
26.7
29.4
lb./ft3
kg/m3
62.366
62.366
62.301
(62.274)
62.261
62.216
62.166
999.01
998.53
997.97
(997.53)
997.32
996.60
995.80
a
The indicated size of container may be used to test aggregate of a maximum nominal size and
equal to or smaller that listed
b Based on sieves with square openings
22 | P a g e
Experiment 5: Determination of Moisture Content of Aggregates
Discussion:
This method describes a rapid procedure in the field for determining the percentage of
surface moisture in both fine and coarse aggregate by displacement in water or by oven dry
method. Surface moisture is defined as moisture in excess of that contained by the aggregate
when in a standard surface dried condition. This is the value desired in correcting the batch
masses for the Portland cement concrete. The accuracy of the methods depends upon the
accurate information on the bulk specific gravity of the material in a saturated surface dry
condition.
Objective: To determine the percentage of surface moisture in both fine and coarse aggregate.
Referenced Documents: ASTM (C 566-96, C 127, C 128, C 125)
Apparatus:
Balance, sensitive to 0.01 gm
Sample container
Stirrer or spoon or spatula
Flask or Pycnometer
Small rubber syringe or medicine dropper
Procedure:
Method A – Pycnometer or Flask Method
1. Obtain a representative sample or specimen of fine and coarse aggregate.
2. Fill the Pycnometer with water at temperature of between 18°C - 29°C (65°F -85°F) to
mark taking care not to trap air bubbles. The final increments of water shall be added
using a syringe or medicine dropper.
3. Thoroughly wipe any excess water from the outside of the container and determine the
weight (mass) to the nearest 0.1 gm.
4. Empty the container and partially fill enough water to cover the specimen when
introduced.
5. Introduce the weighted specimen into the container and remove the entrapped air by
using a vacuum or by stirring and carefully rolling or shaking the container unit no
significant air bubbles rise to the surface.
6. Completely fill the container with water to the original mark, wipe off any excess water
and determine the weight (mass) to the nearest 0.1 gm.
23 | P a g e
Calculation:
% SURFACE MOISTURE 
V D
 100%
W C
Where:
C = weight (mass) of Pycnometer filled with water
W = weight (mass) of Pycnometer, specimen and water
V = weight (mass) of displaced water = C+S-W
S = weight (mass) of specimen
D = weight (mass) of specimen divided by the bulk specific gravity of Aggregate in saturated
surface dry condition = S/G
G= bulk specific gravity of aggregate in saturated dry condition
Method B – Oven Dry
1. Obtain a representative sample of aggregate. For fine aggregate, obtain a specimen with
a weight (mass) of approximately 500 gm. For coarse aggregate, obtain a specimen of
approximately 100 gm.
2. Identify and weigh sample container.
3. Put the sample aggregate into a container.
4. Weigh the container with sample aggregate to the nearest 0.1 gm.
5. Dry the sample to a constant weight (mass) at 110°C ± 5°C (230°F ± 9°F).
6. When dry, weigh to the nearest 0.1 gm. And record as oven dry.
Calculation:
1. The percentage of moisture in an oven dry basis:
% Moisture Oven Dry Basis =
𝑊𝑒𝑡.𝑊𝑡.−𝐷𝑟𝑦 𝑊𝑡.
𝐷𝑟𝑦 𝑊𝑡.
𝑥100%
Wet Wt. = original weight (mass) of aggregate
Dry Wt. = oven dry weight (mass) of aggregate
2. Calculate the percent surface (free) moisture:
% Surface Moisture = (% Moisture, Oven Dry Basis) (% Absorption, from Mix Design)
24 | P a g e
Experiment 6: Making and Curing of Test Specimens
Discussion:
This practice covers procedure for making and curing concrete test specimens of the
concrete in the laboratory under accurate control of materials and test conditions using concrete
that can be consolidated by rodding or vibration. The values stated in either in pounds units or SI
units shall be regarded separately as standards. The SI units are shown in brackets. The values
stated in each system are not exact equivalent; therefore, each system shall be used
independently of each other. Combining values from two systems may result in non –
conformance.
This practice provides standardized requirements for preparation of materials, mixing
concrete, and making and curing concrete test specimens under laboratory conditions. If the
specimen preparation is controlled, the specimen may be used to develop information for the
following purposes:
1.
2.
3.
4.
Mixture proportioning for concrete project
Evaluation of different mixtures and materials
Correlation with nondestructive tests.
Providing specimens for research purposes.
The number of specimens and the number of test batches are dependent on the established
practice and the nature of test program. Usually three or more specimens should be prepared
for each test age and test conditions unless otherwise specified.
Objective: To produce and cure concrete test specimens in the laboratory under accurate
control and test conditions using concrete that can be consolidated by rodding or vibration.
Referenced Documents: ASTM (C 192, C192M-95, c 31/31M-95, C 470-94, C 617-94)
AASHTO (T 126-70, T119-74)
Apparatus:
1.
2.
3.
4.
5.
6.
7.
8.
9.
Cylindrical molds
Tamping rod, 5/8” (16mm) inch diameter and 3/8” (10mm) inch diameter
Trowel or shovel
Slump Cone device
Sampling and mixing pans
Balance
Air content Device (optional)
Vibrator (optional)
Mixer (optional)
25 | P a g e
Mixing Concrete
1. Mix concrete in a suitable mixer or by hand in batches as to leave about 10% excess after
molding the test specimens. Hand Mixing procedures are not applicable to air entrained
concrete or concrete with no measurable slump. Hand mixing should be limited to
batches of 1/4 ft3 (0.007 m3) volume or less.
2. In the case of mixing, add the cored aggregate, some of the, mixing water, and the
solution of admixture (if required), to the mixer before starting its rotation. Start the
mixer, and then add the fine aggregate, cement, and water with the mixer running if it is
impractical for a particular test to add the fine aggregate, cement, and water while the
mixer is running, these components may added to the stooped mixer permitting it to turn
a few revolutions following charging with a coarse aggregate and some of the water. Mix
the concrete, after all the ingredients are in the mixer for 3 minutes followed by 3 minute
to rest, followed by a 2 minute final mixing. To eliminate segregation, deposit machine
mixed concrete in the clean, damp mixing pan and remix by shovel or trowel until it
appears to be uniform.
3. In the case of hand mixing, mix batch in a watertight, clean, damp, metal pan or bowl
with a bricklayer’s blunted towel.
4. Mix the cement, powdered in soluble admixture (if required) and fine aggregate without
the addition of water until they are thoroughly blended.
5. Add the coarse aggregate and mix the entire batch without addition of water until the
coarse aggregate is uniformly distributed throughout the batch.
6. Add water, and admixture solution if use, and mix the mass until the concrete is
homogeneous in appearance and has desired consistency.
7. Select portions of the batch of mixed concrete to be used in the tests for molding
specimens so as to be representative of the actual proportions and conditions of the
concrete. When the concrete is not being remixed or sampled cover it to prevent
evaporation.
8. Measure the slump of each batch immediately after mixing.
9. Mold the specimen as near as practicable to the place where they are to be stored during
the first 24 hours. If it is not practicable to mold the specimens where they will be stored,
move them to the place of storage immediately after being struck off. Place molds on a
rigid surface free from vibration and other disturbances. Avoid harsh striking, tilting, or
scarring of the surface of the specimens when moving to the storage place.
10. Place the concrete in the molds using a scoop, blunted trowel, or shovel. It may be
necessary to remix the concrete in the mixing pan with a shovel to prevent segregation
26 | P a g e
during molding of specimens. Distribute the concrete by the use of tamping rod prior to
the start of the consolidation. In placing the final layer, the operator shall attempt to add
an amount of concrete that will exactly fill the after compaction. Do not add nonrepresentative samples of concrete to an under-filled mold.
11. Place the concrete in the mold, in the required number of layers of approximately equal
volume. Rod each layer with rounded end of the rod using the number of strokes and size
of the rod specified. Rod the bottom layer throughout its depth. Distribute the strokes
uniformly across the cross section of the mold and for each upper layer allowing the rod
penetrate about ½ inch (12 mm) into the underlying layer when the depth of layer is less
than 4 inches (100 mm) and about 1 inch (25 mm) when the depth is 4 inches (100 mm).
After each layer is rodded, tap the outside of the mold lightly 10 to 15 times with mallet
to close any holes left by rodding and to release any large bubbles that may have been
trapped.
Curing
12. To prevent the evaporation of the water from the unhardened concrete cover the
specimens immediately after finishing with non-absorptive, nonreactive plate or sheet of
tough, durable, impervious plastic.
13. Remove the specimens from the molds 24 ± 8 hours after casting.
14. Unless otherwise specified, all specimens shall be moist cured at 23°C ± 2°C (73°F ± 3°F)
from the time of molding until the moment of test. Test specimens shall have free water
maintained on the entire surface area at all times.
27 | P a g e
Experiment 7: Determination of Compressive Strength of Cylindrical
Concrete Specimen
Discussion:
Concrete mixture can be designed to provide a wide range of mechanical and durability
properties to meet the design requirements of the structure. The compressive strength of
concrete is the most common performance measure used by the engineers in designing
buildings and other structures. The compressive strength is measured by breaking the cylindrical
concrete specimens in a compression testing machine. The compressive strength is calculated
from the failure load divided by the cross-sectional area resisting the load and reported in units
of pound-force per square inch (psi) in English system or MegaPascals (MPa) in SI units. Concrete
compressive strength can vary from 2500 psi (17 Mpa) for residential concrete to 400 psi (28
MPa) and higher in commercial structures. Higher strength up to and exceeding 10,000 psi
(70MPa) are specified for certain applications.
Compressive strength test results are primarily used to determine that the concrete
mixtures are delivered meets the requirements of the specified strength, f’c in the job
specifications.
Design engineers use the specified strength f’c to design structural elements. Their
specified strength is incorporated in the job contract documents. The concrete mixture is
designed to produce an average strength of f’c higher than the specified strength such that the
risk not complying with the strength specifications is minimized. To comply with the strength
requirements of a job specification both the following criteria shall apply:
The average of three consecutive tests should equal or exceed the specified strength, f’c
No single strength test should fall below f’c by more than 500 psi (3.45 MPa) or by more than
0.10f’c when f’c is more than 5,000 psi (345 MPa).
It is important to understand that an individual test falling below f’c does not necessarily
constitute a failure to meet specifications requirement. When the average of strength test on a
job are to be required, f’c the probability that an individual strength tests will be less than the
specified strength which is about 10% and this is accounted for the acceptance criteria.
When the strength test results indicate that the concrete delivered fails to meet the
requirements of the specifications, it is important to recognize that the failure may be in testing
not the concrete.
Objective: To determine the compressive strength of cylindrical concrete specimens such as
molded concrete cylinder.
Referenced Documents: ASTM (C 39-94), C39/C 39-01, C 31, C 617, C 873
28 | P a g e
Apparatus:
1.
2.
3.
4.
Universal testing machine
Measuring Device
Balance, sensitive to 0.1 gm
Capping device
Procedure:
1. Compression tests on specimens shall be made as soon as practicable after removal from
the moist storage. A 28-day test shall be performed within ±20 hours of 28th day. Test
specimens shall be kept moist by any convenient method during the period between
removals from moist storage and testing. They shall be tested in moist condition.
2. The test specimens for a given test age shall be broken with in permissible time tolerance
prescribed below.
Test Age
24 hours
3 days
7 days
28 days
90 days
Permissible Tolerance
± 0.5 hours or 2.1%
2 hours or 2.8%
6 hours or 3.6%
20 hours or 3.0%
2 days or 2.2%
3. With a clean rag or brush clean the bearing faces of the bearing blocks, test the
specimens and extrusion controller (elastomeric caps).
4. Rest the specimen on the lower extrusion controller, place the top extrusion controller
on the specimen, and check the spacing between the sides of the specimen and the
extrusion controllers to ensure no contact between the cylinder and the steel. Slide the
specimen and extrusion controller configuration into the center of the concentric circles
of the lower bearing block. Check the alignment with the upper bearing face after
lowering it into position.
5. Apply the load to the specimen. During the first half of the anticipated loading phase a
higher loading rate shall be 20 to 50 psi/second. For 4 inch (100 mm) diameter specimen,
the loading rate shall be 250 t0 260 lbs/second.
6. Apply the load until the specimen fails, and record the maximum load supported by the
specimen during the test rounded to the nearest 500 lb.
29 | P a g e
Calculation:
CS 
Q
R 2
Where:
CS = compressive strength (psi)
Q = load at failure (lb-force)
R = radius of specimen (in)
For 6 inch (150 mm) diameter specimen = Q/28.274
For 4 inch (100 mm) diameter specimen = Q/12.566
30 | P a g e
Experiment 8: Determination of Setting Time of Hydraulic Cement
Discussion:
Cement paste setting time is affected by a number of items including: cement fineness,
water-cement ratio, chemical content (especially gypsum content) and admixtures. Setting time
test are used to characterize how a particular cement paste sets. For construction purposes, the
initial set must not be too soon and the final set must not be too late. Additionally setting times
can give some indication whether or not cement is undergoing normal hydration. (PCA, 1988).
To ensure sufficient time to take place concrete while it remain plastic, a minimum limit
is imposed on the time of “initial” set, which may be taken as a condition of the ,ass when it
begins to stiffen appreciably. ASTM specification requires that the initial set should not take
place within one hour. Depending on the test used to determine it, the initial usually takes place
within two hours to four hours. To ensure that cement will harden for use, a maximum limit is
imposed on the time of “final” set. ASTM specification requires that the final set occur within 10
hours. With much commercial cement final set occurs within five to eight hours. The condition of
initial and final set is determined by penetration of standard needles or rods into a neat”)
(straight cement) paste of specified consistency.
Both common setting time test, the Vicat needle and the Gillmore needle, define the
initial set and final set based on the time at which a needle of particular size and weight either
penetrates a cement paste sample to a given depth or fails to penetrate a cement past sample.
Time of setting by Vicat needle – initial setting occurs when a 1-mm needle penetrates 25 mm
into cement paste. Final set occurs when there is no visible penetration.
Time of setting by Gillmore needle – initial set occurs when a 113.4 grams Gillmore needle (2.12
mm in diameter) nails to penetrate. Final set occurs when a 453.6 grams Gillmore needle (1.06
mm in diameter) fails to penetrate.
The Vicat needle test is more common and tends to give shorter times than Gillmore
needle test.
ASTM C 150 SPECIFIED SET TIMES BY TEST METHOD
Test Method
Vicat
Gillmore
Set Type
Initial
Final
Initial
Final
Time Specification
≥45 minutes
≤375 minutes
≥60 minutes
≤600 minutes
31 | P a g e
Objective: To determine the time setting of hydraulic cement by the use Vicat needle.
Referenced Documents: ASTM (C 191-82, C 191-04, C 403/C403M-99, C 266)
AASHTO (T 131, T 154)
Apparatus:
1.
2.
3.
4.
5.
Balance, sensitive to 0.1 gm.
Vicat needle apparatus
Graduated Cylinder, 200 or 250 ml capacity
Trowel or Spatula
Mixing container
Procedure:
1. Mix 650 gm of cement with the percentage of mixing water required for normal
consistency.
2. Quickly form the cement paste into a ball with gloved hands and tossed six times from
one hand to another maintaining the hands about 6 inches (152 mm) apart.
3. Press the ball, resting in the palm of hand, into a larger end of the conical ring held on the
other hand completely filling the ring with paste.
4. Remove the excess of the larger end by a single movement of the palm of the hand.
5. Place the large end on a glass plate and slice off the excess paste at the smaller end at the
top of the ring by a single oblique stroke of a sharp edged trowel or spatula held at a
slight angle with the top ring.
6. Smooth the top of the specimen, if necessary, with one or two light touches of the
pointed end of the trowel.
7. During the operation of cutting and smoothing, take care not to compress the paste.
8. Place the test specimen in the most closet or moist room immediately after molding and
allow it to remain there except when determination of times setting are being made. The
specimen shall remain in the conical mold throughout the test period.
9. Allow the time of setting specimen to remain in the moist cabinet for 30 minutes after
molding without being disturbed.
32 | P a g e
10. Determine the penetration of the 1 mm needle at this time and every 1.5 minutes
thereafter until the penetration of 25 mm or less is obtained.
11. For penetration test, lower the needle of the rod until it rests on the surface of the
cement paste. Tighten the setscrew and set indicator at the upper end of the scale. Take
an initial reading. Release the rod quickly by releasing the setscrew and allow the needle
to settle for 30 seconds and take the reading to determine the penetration. No
penetration tests shall be made closer than ¼ in. (6.4 mm) from any previous penetration
and no penetration shall be made closer than 3/8 in (9.5 mm) from the inside of the
mold.
12. Record the results all penetration tests and by interpolation determine the time when a
penetration of 25 mm is obtained. This is the initial setting time. The final setting time is
when the needle does not sink visibly into the paste.
33 | P a g e
EXPERIMENT NO. 8: WORKSHEET REPORT
TIME OF SETTING OF HYDRAULIC CEMENT
NAME: _______________________
TESTED BY: ________________________
DATE: _______________________
Specimen No.
Time (second)
Penetration (mm)
34 | P a g e
Experiment 9: Determination of Penetration of Bituminous Materials
Discussion:
The penetration test is used as a measure of consistency. Higher values of penetration
indicate softer consistency.
Apparatus:
1. Penetration Apparatus – any apparatus that permits the needle holder (spindle) to move
vertically without measurable friction and is capable of indicating the depth of
penetration to the nearest 0.1 mm, will be accepted. The weight of the spindle shall be
47.5 ± 0.05 g. the total weight of the needle and spindle assembly shall be 50.0 ± 0.05g.
Weights of 50 ± 0.05 g and 100 ± 0.05 g shall be provided for total loads of 100 g and 200
g, as required for some conditions of the test. The surface on which the sample container
rests shall be flat and the axis of the plunger shall be approximately 90C to this surface.
The spindle shall be easily detached for checking its mass.
2. Penetration Needle – the needle shall be made from fully hardened and tempered
stainless steel, Grade 440C or equal, HRC 54 to 60. It shall be approximately 50 mm (2
min.) in length and 1.02 mm (0.0394 to 0.0402 in.) in diameter. It shall be symmetrically
tapered at one end by grinding to a cone having an angle between 8.7 and 9.7° over the
entire cone length and whose axis within 0.0127 mm (0.005 in.) maximum run out (total
indicator reading). After tapering, the point shall be ground off to truncated cone, the
smaller base of which shall be from 0.14 to 0.16 mm (0.0055 to 0.0063 in.) in diameter.
The truncation shall be square with the needle axis within 2 degrees and the edge shall
be sharp and free from burrs.
3. Sample container – a metal or glass cylinder, flat-bottom container of essentially the
following dimensions shall be used:
For penetrations below 200:
a. Diameter, mm
b. Internal depth, mm
55
35
For penetrations between 200 and 500:
c. Diameter, mm
d. Internal depth, mm
70
45
4. Water Bath – a bath having a capacity of at least 10 liters and capable of maintaining a
temperature of 25°C or any other temperature of test within 0.1°C.
5. Transfer Dish – when used, the transfer dish for the container shall be cylinder with a flat
bottom made of glass, metal, or plastic. It shall be provided with some means which will
35 | P a g e
ensure a firm bearing and prevent rocking of container. It shall have minimum inside
diameter of 90 mm (3.4 in.) and a minimum depth above the bottom bearing of 55 mm
(2.17 in.).
6. Timing Device – for hand-operated penetrometers any convenient timing device such as
an electric timer, a stop watch, or other spring operated device may be used provided it
is graduated in 0.1 s or less and is accurate to within ± 0.1 s for a 60-s interval.
7. Thermometer – calibrated liquid- in-glass thermometer of suitable range with
subdivisions and maximum scale error 0f 0.1°C (0.2°F) or any other thermometric device
of equal accuracy, precision and sensitivity shall be used.
Preparation of Sample
1. Heat the sample with care to prevent local overheating until it has become fluid. Then
with constant stirring, raise the temperature of the asphalt sample not more than 100C
or 180F above its expected softening point or tar-pitch sample not more than 56C. Avoid
the inclusion of air bubbles. Then pour it into the sample container to a depth such that,
when cooled to the temperature of test, the depth of the sample is at least 10 mm
greater than the depth to which the needle is expected to penetrate. Pour separate
samples for each variation in test conditions.
2. Loosely cover each container and its content as a protection against dust, and allow to
cool in an atmosphere at a temperature not higher than 30C or 865F and no lower than
20C or 680F for not less than 1-1/2 h nor more than 2 h when the sample is in a 175 ml (6
oz.) container and not less than 1 h nor more than 1 ½ h when the sample is in 90 ml (3
oz.) container. Then place the sample in the water bath maintained at the prescribed
temperature of test, along with the transfer dish if used, and allow it to remain for not
less than 1 ½ h nor more than 2h when the sample is in the 1754 ml (6 oz.) container, and
for not less than 1 nor more than 1 ½ h when the sample is in 90 ml (3 oz.) container.
Test Condition
1. Where the conditions of test are not specifically mentioned, the temperature, load, and
time are understood to be 25°C (°F), 100 g and 5 sec, respectively. Other conditions of
temperature, load, and time may be used for special testing, such as:
Temperature
0°C (32°F)
4°C (39.2°F)
46.1°C (115°F)
Load, g
200
200
50
Time
60
60
5
In such cases, the specific conditions of test shall be reported.
36 | P a g e
Procedure:
1. Examine the needle holder and guide to establish the absence of water and other
extraneous matter. Clean the penetration needle with toluene or other suitable solvent,
dry with a clean cloth and insert the needle in the penetrometer. Unless otherwise
specified, place the 50-g weight above the needle, making the total moving load 100 ±
0.01g. If test are made with the penetrometer in the bath, place the sample container
directly submerged stand of the penetrometer. Keep the sample container completely
covered with the water bath. If tests are made with penetrometer outside the bath, place
the sample container in the transfer dish, cover the container completely with water
from the constant temperature bath and place the transfer dish on the stand of the
penetrometer. In either case, position the needle by slowly lowering it until its tip just
make contact with the surface of the sample. This is accomplished by bringing the actual
needle tip into the contact with its image reflected by the surface of the sample from a
properly source of light. Either note the reading of the penetrometer dial or bring the
pointer to zero. Quickly release the needle holder for the specified period of time and
adjust the instrument to measure the distance penetrated in tenths of a millimeter. If the
container moves, ignore the result.
2. Make at least three determinations at points on the surface of the sample not less than
10 mm from the side of the container and not less than 10 mm apart. If the transfer dish
is used, return the sample and transfer dish to the constant temperature bath between
determinations. Use a clean needle for each determination. If the penetration is greater
than 200, use at least three needles leaving them in the sample until the three
determinations have been completed.
Note 1 – For referee tests, penetrations at temperatures other than 77°C (25°F) should be
made without removing the sample from the bath.
3. The needles, container, and other conditions described in this method provide for
determinations of penetrations up to 350. However, the method may be used for direct
determinations up to 500 provided special container and needles are used. The container
shall be at least 60 ml in depth. The over-all volume of material in the container should
not exceed 125 ml to permit proper temperature adjustment of the sample.
37 | P a g e
Calculation and Reporting:
1. Report to the nearest whole unit the average of at least three penetrations whose values
do not differ by more than the amount shown below:
Penetration
0
50
150 250
to
to
to
to
49
149 249 over
----------------------------------------Maximum difference
Between the highest and
Lowest determinations
2
4
6
8
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Experiment 10: Determination of Modulus of Rupture of Concrete
Beam
Discussion:
Flexural strength is a measure of tensile strength of concrete. It a measure of
unreinforced concrete beam or slab to resist failure in bending. It is measured by 6 x 6 inches
(150 mm x 150 mm) concrete beam with a span length of at least three times the depth. The
flexural strength is expressed as Modulus of Rupture (MR) in psi (MPa) and is determined by
standard test ASTM C 78 (Third-point loading) and ASTM C 293 (center point loading).
Flexural (MR) is about 10 to 20 percent of the compressive strength depending on the
type, size and volume of coarse aggregate used. However, the best correlation for specific
materials is obtained by laboratory test for given materials and mix. The MR is determined by
third-point loading is lower that the MR determined by center-point loading by as much as 15%.
Designer of pavement use a theory based on flexural strength. Therefore, laboratory mix
design based on flexural strength test may be required or a cementitous material content may
be selected from past experience to obtain the needed design MR. Some also use MR for field
control and acceptance of pavements. Very few use flexural testing for structural concrete.
Agencies not using flexural strength for field control generally find the use of compressive
strength convenient and reliable to judge the quality of the concrete delivered.
Flexural strength are extremely sensitive to specimen preparation, Handling, Curing
procedure. Beam specimens are very heavy, allowing a beam to dry will yield lower strength.
Beam must be cured in a standard manner and tested while wet. A short period of drying can
produce a sharp drop in flexural strength.
May state highway agencies have use flexural strength but are now changing to
compressive strength for job control of concrete paving. Cylinder strengths are also used for
concrete structures.
The concrete industry and inspection agencies are much familiar with traditional cylinder
and compression test for control and acceptance of concrete. Flexure can be used for design
purposes, but the corresponding compressive strength should be used to order and accept of the
concrete. Any time trial batches are made, both flexural and compressive test should be made so
that correlation can be developed for filed control.
Objective: To determine the flexural strength of concrete specimens by the use of simple beam
with center point loading.
Referenced Documents: ASTM (C 293-94, C 78-94, C 31, C 192, C 293-02)
AASHTO (T 198-74, 23)
ACI (325, 330)
39 | P a g e
Apparatus:
Universal Testing Machine
Loading apparatus
Procedure:
1. Measure the dimensions of the specimen and record them in the data sheet.
2. Turn the specimen on its side with respect to its position as molded and center in on the
support blocks.
3. Center the loading system in relation to the applied force.
4. Bring the load applying – block in contact with the surface of the specimen at the center
and apply a load between 3 and 6% of the estimated load.
5. Grind cap, or use leather shims on the specimen contact surface to eliminate any gap in
excess of 0.004 in. (0.10 mm). Gaps in excess of 0.15 in. (0.38 mm) shall be eliminated by
capping or grinding.
6. Apply the load on the specimen continuously and without shock. The load shall be
applied at a constant rate to the breaking. Apply the load at such rate that constantly
increases the extreme fiber stresses between 125 and 175 psi/min. (0.86 and 121
MPa/min) when calculated in accordance with 7.1 until rupture occurs.
7. Take three measurements across each dimensions (one at each edge and at the center)
to the nearest 0.05 in. (1mm) to determine the average width and depth of the specimen
at the point of fracture. If the fracture occurs at a capped section include the cap
thickness in measurement.
Calculation:
MR =
3PL
2bd2
Where:
MR = modulus of rupture, in psi (MPa)
P = maximum load applied as indicated by testing machine in lb (N)
L = span length, in inches (mm)
b = average width of specimen in inches (mm)
d = average depth of specimen at the fracture in inches (mm)
Note: The weight of the beam is not included in the above calculation.
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Experiment 11: Determination of Tensile Strength of Concrete Cylinder
Discussion:
Concrete has very low in tensile strength due to in homogeneous nature of the material.
When loaded in tension it typically fails along the interface between the aggregate and cement.
Measuring tensile strength of concrete directly is very difficult (i.e., grasping the ends of along
specimen and pulling); therefore, indirect method is used. The procedure involves loading a right
cylinder on its side, until splits down the center.
Objective: To measure the splitting tensile strength of concrete by the application of a diametric
compressive force on a cylindrical concrete specimen placed with its axis horizontal between the
platens of testing machine.
Referenced Documents: ASTM (C 496-96, C 498-71, C 496)
AASHTO (T 198-74, T 23, T 126)
ACI 318-63
Apparatus:
1.
2.
3.
4.
Testing Machine capable of 10,000 lb.
Concrete test cylinder
Bearing strips
Supplementary bearing bar or plate
Test Specimen:
1. Moist cured specimens during the period between their removal from the curing
environmental and testing, shall be kept moist by a wet burlap or blanket covering, and
shall be tested in a moist condition as practicable.
2. Specimen tested at 28 days shall be in an air-dry condition after 7 days moist curing
followed by 21 days at 23°C ± 1.7°C (73°F ± 3°F) and 50 ± 5% relative humidity.
Procedure:
1. Measure the dimension of the cylinder. Determine the diameter of the specimen to the
nearest 0.01 in (0.25 mm) by averaging three diameters measured near ends and the
middle of the specimen and lying in the plane containing lines mark on two ends.
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2. Determine the length of the specimen to the nearest 0.1 inch (2.5 mm) by averaging at
least two length measurements taken in the plane containing the lines marked on the
two ends.
3. Center one of the plywood strips along the center of the lower bearing block of the
testing machine. Place the cylinder on the plywood strip and align so that the lines
marked on the ends of the specimen are vertical and centered over the plywood strip.
4. Place the second plywood strips lengthwise on the cylinder and place a 2”x2”x14” steel
bar over the plywood strip.
5. Lower the upper loading head until the assembly is secured in the machine.
6. Apply the compressive load slowly and continuously until failure. The rate at which the
specimen should be loaded is 100 to 200 psi (690 to 1380 Kpa) per minute.
7. Record the maximum load applied, the type of failure and appearance of the concrete
specimen.
CALCULATION:
𝑇=
2Pmax
πLD
Where:
T= splitting tensile strength, psi (kPa)
Pmax = maximum applied load, lb.-force (KN)
L = length, in (mm)
D = diameter, in (mm)
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Experiment 12: Determination of Static Bending of Wood
Discussion:
Most structures and machine have primary function is to resist loads that cause bending.
Examples mare beams, hooks, plates slabs, and columns under eccentric loadings. The design of
such structural members may be based on tensile compressive, and shearing properties
accounted by various bending formulas. In many instances, however bending formula give
results that only approximate the real conditions. The bending test may serve then as a direct
means of evaluating behavior under bending loads, particularly for determining limits of
structural stability of beams of various shapes and sizes.
Flexural test on beams are usually made to determine the strength and stiffness in
bending; occasionally they are made to obtain a fairly complete picture of stress distribution in a
flexural member. Beam test also offer a means of determining the resilience and toughness of
material in bending.
If a beam specimen is to be tested for flexural failure, as in the case when modulus of
rupture of a material is to be determined, it must be proportional that it does not fail by lateral
buckling or in shear before the ultimate flexural strength is reached. In order to avoid shear
failure, the span must not be too short with respect to the depth. For wood, small clear pieces of
wood, 50 x 50 x 750 mm (2x2x30 in.) in size, are tested under center loading, but large timber
beam having a length of 5 m are often tested under third point loading.
Objective: To determine the mechanical properties of wood subjected to bending and to study
failure of the material.
Referenced Documents: ASTM (D 143-83, D 198-84)
Apparatus:
1. Universal Testing Machine
2. Beam support
3. Deflection gage
43 | P a g e
Procedure:
1. Mark the center and end points of the specimen for a 30-in. span.
2. Place the beam in the machine with ends placed on the supports and place the loading
block at the center of the beam. The whole assembly shall properly centered in such that
the loading block is at the center of the machine’s loading head.
3. Lower the loading until a small compressive load is applied to the beam. Place the
deflection gage at the midspan in such a way that it can measure the midspan deflection
of the beam.
4. Apply the load continuously at the rate of approximately 1000 pound per minute. Take
simultaneous load and deflection readings for increment of every 200 pounds until the
maximum load has been reached. Remove the load gage prior to the failure of the beam.
5. Sketch the appearance of the failure.
6. Plot a load deflection curve and compute all the properties called using the formula
shown below.
Calculation:
MR 
E
3Pmax L
2bh 2
PL3
 4bh 3
Where:
Pmax and L = maximum load and span of the beam
b and h = width and height of the cross section
 = slope of the load deflection curve
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Experiment 13: Determination of Compressive Strength of Wood
Parallel to Grain
Discussion:
Compression test is merely the opposite of the tension test with respect to the direction
or sense of the applied forces. Compression parallel to the grain shortens the fibers in the wood
lengthwise. An example would be chair or table legs, which are primarily subjected to
downward, rather than lateral pressure. Wood is very strong in compression parallel to grain and
this is seldom a limiting factor in design. Specimen for compression test of small, clear pieces of
wood parallel to the grains must be 50 x 50 x 150 mm (2 x x2 x 6 in.) or 50 x 50 x200 mm.
Objective: To determine the compressive strength of wood parallel to the grain.
Referenced Documents: ASTM D 143-83
Apparatus:
1.
2.
3.
4.
Compression Machine
Compressometer
Load indicator
Bearing Block
Procedure:
1. Measure the cross section and length of the specimen to the nearest 0.01 inches. Record
the dimensions and indicate the species of wood.
2. Place the specimen in the machine. Adjust dials or compressometer. Have an instructor
check before starting the test.
3. Apply the loads continuously throughout at the rate 0f 0.003 in/in of the specimen length
per minute.
4. Record the maximum load to a point beyond the proportional limit. After failure, draw
sketches and identify the type of failure. In case two or more kinds of failure develop all
shall be described in the order of their occurrence.
5. Compute compressive strength in psi.
Calculation:
S
MaximumLoad
AreaofBearing
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Experiment 14: Determination of Shear Stress of Wood Parallel to
Grain
Discussion:
Shear stress involves the application of stress from two opposite direction causing
portions of an object to move parallel but opposite directions. Wood is very resistant to shearing
perpendicular to the grain and this property is not measured via a standard test. Wood shears is
much easier in a direction parallel to grain – consider a crew running perpendicular to the grain;
it will shear out to the nearest end grain if a sufficiently large force is applied to the board
parallel to the grain. Shear stress is measured in psi.
A shear strength parallel to the grain ranges from 3 to 15 MPa at 12% moisture content.
Because wood is highly orthotropic, it is very difficult to get fail in shear perpendicular to the
grain usually result in failure in another failure mode, such as compression perpendicular to
grain. A very limited amount of data suggests that shear strength perpendicular to the grain may
be 2.5 – 3 times that of shear parallel to the grain.
Objective: To test the shearing stress parallel to the grain of wood.
Referenced Documents: ASTM D 143-18
Apparatus:
1. Testing machine
2. Caliper
3. Shear tool apparatus
Procedure:
1. Measure and record actual dimensions of the shearing surface.
2. Place the specimen in shear test assembly.
3. Place the assembly in the testing machine. Provide 1/8 inch offset along which failure
occurs.
4. Set dials to monitor rate of load application.
5. Applied continuously throughout at the rate of 0.0004 in/sec until failure.
6. Sketch the failure pattern and compute the shearing stress.
Calculation:
ShearingSt ress 
MaximumLoadApplied
ShearingArea
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Experiment 15: Determination of Moisture Content of Wood
Discussion:
As the moisture content in wood changes, wood expands or contracts and this is in turns
causes a variety of problem. The moisture content of wood is measured as a ratio of the water in
the wood and the weight of the wood itself. This ratio is expressed in percentage.
Freshly forest – cut “green” wood may have moisture content 30% to more than 200%.
Depending on the species. Before using the wood, it needs to be dried to reduce moisture
content. The “ideal” moisture content depends upon the use of wood and its relative humidity at
the place where the wood is to be used. It is critical that the wood you work will be dried down
to within 2 percentage points of the equilibrium moisture content (EMC) of the in use location.
The EMC of air is the numerical MC that will eventually be attained by any piece of wood then
stored indefinitely at a particular humidity. Temperature has a great effect on MC and EMC.
The relative humidity (RH) in most homes and offices in the U.S. (except in coastal areas
and exceptionally dry areas) averages 40 to 40% RH> therefore intended for interior use should
be dried to ^ to 7% MC and should be kept at this MC prior to and during manufacturing.
Relative Humidity and MC/EMC
In use Relative Humidity
EMC
Corresponding MC
19-25
5%
5%
26-32
6%
6%
33-39
7%
7%
40-46
8%
8%
47-52
9%
9%
Two Special Notes:
1. Softwood machine better a little higher MC shrink and swell less than hard word when
MC changes. The target MC for softwood is 78% MC.
2. The term “kiln dried” has no special indication for MC for furniture, cabinet or millwork
manufactures; don’t specify lumber without also adding the actual MC that you want.
47 | P a g e
Wood is cellulosic material, so that is constantly losing or gaining water to or from the
environment. Therefore, it is important to remember that even after the wood has been dried to
the proper MC, MC can change during storage, manufacturing or use.
Objective: To determine the amount of moisture content contained in wood by oven-drying
method.
Referenced Documents: ASTM D 2016
Apparatus:
1. Oven
2. Balance, accuracy ±0.2 percent
3. Measuring Device
Procedure:
1. Weigh the specimen (2”x2”x2”) after cutting from the sample representing the lot or else
protects it from a moisture change until weighed. Weigh the specimen to an accuracy of
± 0.2 percent for example, if the specimen weighs 250 gm, obtain the weight to the
nearest 0.5 gm.
2. After they have been weighed, place the specimens in an oven when convenient and heat
at 103°C ± 2°C (217°F ± 3.6°F) until they reach at constant weight. To test for constant
weight, weigh the heaviest specimens at intervals of 2 hours or more until they show no
further weight loss within the accuracy of weighing required. Avoid drying for period
longer than necessary to achieve constant weight.
3. Weigh each specimen immediately after it is removed from the oven upon attaining
constant weight or store in a desiccator while waiting for weighing. Record the weight.
4. Calculate the moisture content.
Calculation:
Moisture Content (%) =
Original weight of specimen−Oven−dry weight of specimen
Oven−dry weight of specimen
𝑥100
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Experiment 16: Determination of Compressive Strength of Concrete
Hollow Blocks
Discussion:
Hollow masonry units of Portland cement and sand, gravel. Or other suitable aggregate
are termed concrete blocks. Concrete blocks are used for interior and exterior bearing and
nonbearing walls, partitions and backing.
The weight, color, and texture of concrete block depend largely on the type of aggregate
used in its manufacture. Blocks made with sand and gravel or crushed rock weighs 40 to 50 lb
(18.1 kg to 20.4 kg) per 8”x 8”x 16” (203 x 203 x 406 mm) unit. These blocks are produced as
non-load bearing units, for use as backup walls, or as load-bearing units, for use as the finished
surface of both interior and exterior walls.
Standard concrete hollow blocks have typical light-gray color of concrete. Colored blocks
may be made with naturally colored aggregates or by including inert pigments in the concrete
mix.
Lightweight concrete block is used where a lightweight material with good strength and
high insulating or acoustical qualities desired. Its use also simplifies the attachment of finish
materials or accessories to structural wall, in that common nail can be driven into the block.
Objective: To determine the compressive strength of concrete hollow block.
Apparatus: Compression machine
Procedure:
1. Place the bottom of the concrete hollow block on compression block made of 1 inch thick
plywood. Place another 1 inch thick plywood on top of the concrete hollow block.
2. Apply the compression load slowly until failure is attained and record the reading. Take
note of the appearance of the concrete hollow block as well as the type of failure that
will occur.
3. Test a total of three hollow blocks for each batch.
Calculation:
Compressive Strength (CS) =
Where:
P
A
CS = compressive strength of the specimen, psi (kN/m2)
P = maximum load, lb. (KN)
A = cross sectional area of the specimen (m2)
49 | P a g e
Experiment 17: Los Angeles Abrasion Test
Significance:
The Los Angeles test is a measure of degradation of mineral aggregates of standard grading
resulting from a combination of actions including abrasion or attrition, impact, and grinding in a
rotating steel drum containing a specified number of steel spheres. The Los Angeles (L.A.) abrasion
test is a common test method used to indicate aggregate toughness and abrasion characteristics.
Aggregate abrasion characteristics are important because the constituent aggregate in HMA must
resist crushing, degradation and disintegration in order to produce a high quality HMA.
Apparatus:
1. Steel Spherical Balls
2. Machine (The machine is equipped with a counter. The machine shall consist of hollow
steel cylinder closed at both ends. An opening in cylinder shall be provided for
introducing the sample
3. Sieves
4. Aggregate used in highway pavement should be hard and must resist wear due to the
loading from compaction equipment, the polishing effect of traffic and the internal
abrasion effect.
5. The road aggregate should be hard enough to resist the abrasion of aggregate. Resistance
to abrasion is determined in laboratory by loss angles abrasion test.
Procedure:
1. Prepared sample is placed in the abrasion-testing machine.
2. A specified number of steel spheres are then placed in the machine and the drum is
rotated for 500 revolutions at a speed of 30 - 33 revolutions per minute (RPM).
3. The material is then separated into material passing the 1.70 mm (No. 12) sieve and
material retained on the 1.70 mm (No. 12) sieve.
4. Dry the sample in an oven.
5. Calculate %age loss due to Abrasion by calculating the difference between the retained
material (larger particles) compared to the original sample weight. The difference in
weight is reported as a percent of the original weight and called the "percent loss".
50 | P a g e
Principle of Test
To produce the abrasive action by use of standard steel balls which when mixed with the
aggregate and rotated in a drum for specific number of revolution cause impact on aggregate.
The %age wear due to rubbing with steel balls is determined and is known as abrasion value.
Prepare the sample by the portion of an aggregate sample retained on the 1.70 mm (No. 12)
sieve and place in a large rotating drum that contains a shelf plate attached to the outer wall.
Test Adequacy / Suitability:
The L.A. Abrasion test is an empirical test; it is not directly related to field performance of
aggregates. Field observations generally do not show a good relationship between L.A. abrasion
values and field performance. L.A. abrasion loss is unable to predict field performance.
Specifically, the test may not be satisfactory for some types of aggregates. Some aggregates,
such as slag and some limestones, tend to have high L.A. abrasion loss but perform adequately in
the field. L.A. abrasion loss seems to be reasonable well correlated with dust formation during
handling and HMA production in that aggregates with higher L.A. abrasion loss values typically
generate more of dust.
Uses & Significance of LA Abrasion Test:
For an aggregate to perform satisfactory in pavement, it must be sufficiently hard to
resist the abrasive effect of traffic over long period of time. The soft aggregates will be quickly
ground to dust, whilst the hard aggregates are quite resistant to crushing effect.
The test also will determine the quality of the aggregate.
The L.A. Abrasion test is widely used as an indicator of the relative quality or competence of
mineral aggregates.
Standard Test Methods are:


AASHTO T 96 and ASTM C 131: Resistance to Degradation of Small-Size Coarse Aggregate
by Abrasion and Impact in the Los Angeles Machine
ASTM C 535: Resistance to Degradation of Large-Size Coarse Aggregate by Abrasion and
Impact in the Los Angeles Machine
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Experiment 18: Marshall Test of Asphalt
Discussion:
This test method provides a procedure for determining the relative stability (Stabilometer
Value) of an asphalt mix by measuring the transmitted horizontal pressure developed in a
compacted test specimen under a given vertical pressure. This value indicates the ability of the
pavement to resist plastic deformation under the action of traffic.
Apparatus:
1. Stabilometer - The stabilometer is a triaxial device consisting essentially of a rubber
sleeve within a metal cylinder containing a liquid which registers the horizontal pressure
developed by a compacted test specimen as a vertical load is applied.
2. Testing Machine - The Central Lab uses the California Bearing Ratio (C.B.R.) machine to
perform the stabilometer test on Marshall compacted specimens. This machine has a
loading capacity of 60,000 lbs compression which loads from the bottom.
3. Oven - An oven capable of maintaining a temperature of 60° + 30° C.
4. Calibration Cylinder - A hollow metal cylinder 102 + 0.013 mm in outside diameter by 140
mm high (for calibration purposes).
5. Rubber Bulb - For introducing air into the stabilometer.
6. Measuring Device - A device for measuring the height of the specimen to the nearest 0.3
mm (0.01 inches).
7. Follower - One solid wall metal follower 101.2 mm in diameter by 140 mm high.
8. Miscellaneous Apparatus - Balance of 5 kg capacity and sensitive to 1.0 g, metal pans of
various sizes, thermometers, trowels, spatulas, scoops, gloves and beakers.
52 | P a g e
Procedure:
A. Equipment Preparation
Adjust the bronze nut on the stabilometer stage base (if base is of the adjustment
type) so that the top of the stage is 3 1/2 inches below the bottom of the upper tapered
ring. Perform all tests at this stage setting.
Adjust the testing machine so that the platen or head moves at a rate of 0.05
inches per minute when no load is being applied. This adjustment is performed with the
stabilometer and stage base on the platen if the testing machine applies the load from
the lower platen. Hydraulic testing machines must be run several minutes before the oil
warms up sufficiently to maintain a constant speed.
Place the standard metal specimen (preheated to 60 + 3o C) in place in the
stabilometer. Seat it firmly on the stage and by holding it in place with either the hand or
a confining load of 100 pounds in the testing machine, turn the pump to a pressure of
exactly 5 psi. Adjust the turn’s indicator dial to zero. Turn the pump handle at an
approximate rate of two turns per second until the stabilometer dial reads 100 psi. The
turn’s indicator dial shall read 2.00 + .05 turns. If it does not, the air in the cell must be
adjusted. Remove or add air by means of the valve and the rubber bulb and repeat the
displacement measurement after each air change until the proper number of turns is
obtained. Release the horizontal pressure and remove the standard metal specimen.
B. Sample Preparation
Test specimens at 60 + 3o C. If desirable to test with moisture present in the
mixture, however, test at room temperature.
C. Test Procedure
Transfer the test specimen from oven to the stabilometer. Make sure that the
specimen goes into the stabilometer straight and is firmly seated level on the base.
Place the follower on top of the specimen and adjust the pump to give a
horizontal pressure of 5 psi (the 5 psi pressure should be exact as a deviation of as little
as 1 psi has considerable effect on the final value).
Start movement of testing machine platen or head at a speed of 0.05 inches per
minute and record the horizontal pressures (stabilometer gauge readings) when the
vertical loads are 3000, 5000 (400 psi) and 6000 lbs.
Stop the vertical loading exactly at 6000 lbs and immediately reduce the load to
1000 + 100 lbs. Turn the displacement pump so that the horizontal pressure is reduced to
53 | P a g e
exactly 5 psi. This will result in a further reduction in the vertical load which is normal and
for which no compensation is necessary. Set the turn’s displacement indicator dial to
zero. Turn the pump handle at approximately two turns per second until the stabilometer
gauge reads 100 psi. During this operation the vertical load registered on the testing
machine will increase and in some cases exceed the initial 1000 lb. load. As before, these
changes in testing machine loading are characteristic and no adjustment or
compensation is required.
Results and Calculation:
1. Collection of Test Results
Record the number of turns indicated on the dial as the displacement of a specimen. The turns
indicator dial reads in 0.001 in., and each 0.1 in. is equal to one turn. Thus, a reading of 0.250 in.
indicates that 2.50 turns were made with the displacement pump. This measurement is known
as turns displacement of the specimen.
2. Calculations
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Experiment 19: Tensile Test of Steel Bars
Discussion:
Most commercial specification for metals has requirements for physical properties as
determined by the tensile-strength test. The properties include ultimate strength, yield strength
or yield point, elongation, character of fracture, and reduction of area. In order to obtain
complete information concerning tensile properties of a metal, a stress-strain curve should be
determined experimentally. Strain corresponding to definite stresses imposed upon the
specimen is measured by means of extensometer.
For metal having no well-defined yield point, the yield strength is ordinarily determined,
as explained previously. Ductile carbon steel has well defined yield point.
The tension test of steel is quite illustrative for some mechanical properties. If force
determination diagram are drawn, it is very easy to have an idea about the ductility or
brittleness of the material. A ductile material is one which large deformation is produced before
the specimen fractures. Whereas a brittle material is one in which comparatively small
deformations occurs before fracture.
Besides, if the gage length and the original cross section area are known, strain and
stresses can be calculated from the force-deformation diagrams. The yield stresses at which
large plastic deformation begin with small increase in stress, is an important characteristic of
concrete reinforcing steel. Another important stress is the ultimate stress, i.e., the maximum
stress that can be carried by the material without failure.
While plain bars have circular cross sections, so a nominal diameter is defined. Nominal
diameter of a deformed bar is the diameter of the plain bar which has the same weight per unit
length as the deformed bar.
In tension test, percent elongation and percent reduction of area may be considered as
the quantitative measures of ductility. Temperature, rate and type of loading affect the result of
tension test.
Laboratory test show that the increase in yield strength is accompanied by an increase in
tensile strength and hardness, too. However, the increase in tensile strength is not much. On
other hand, strain hardening reduces ductility.
55 | P a g e
Objective: To obtain the force-deformation diagram (stress-strain diagrams) of a plain bar and a
deformed bar of concrete reinforcing steel and compare some of their mechanical properties in
tension.
Referenced Documents: ASTM (A6/A6M, A36/A36M, E8-69)
AASHTO (T 68-74)
Apparatus:
1. Universal Testing Machine
2. Extensometer
3. Vernier caliper
Procedure:
1. Measured the total length L and weight W of the deformed bar specimen. Mark gage
length.
2. Attach the specimen to the universal testing machine (100 ton-capacity).
3. Apply a tensile load satisfying all the requirements of the related standard.
4. Obtain the force-deformation diagram (stress-strain diagram) as graphs from the
mechanical recorder of the machine. Reload the ultimate load PU. Continue until load
fracture of the specimen.
5. Measure the age length after fracture (Lr) by connecting the two pieces.
6. Measure the final diameter dfd by Vernier. Make about three mutual measurements.
7. Make calculation:
(a) Determine the nominal diameter dn (mm) of the deformed bar using dn = 12.8G0.5
G = weight/unit length (kg/m) which can be calculated using L and W
(b) Calculate the yield strength of the bar as σy
(c) Calculate the ultimate strength of the bar as σu using the ultimate load Pu and Ao
Ao = original cross-sectional area
Pu = read from graph
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(d) Calculate the modulus of elasticity E for the bar using:
σy - σy (P2/ An) - (P1/ An)
(e) Calculate the percent reduction in area using:
Ao - An
(f) Calculate percent elongation using:
Lf - Li
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REFERENCES
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