World Cannot form / sustain without water – Devine Poet Thiruvalluvar more than 2000 years back Concrete Construction Concrete Construction One of the important factors for concrete structure to be sustainable is ……………..Durability Concrete Construction Prof.Basheer Self Compacting Concrete (SCC) 6 Self Compacting Concrete (SCC) SCC can be defined as.. • A concrete that is able to flow under its own weight and completely fill the formwork, even in the presence of dense reinforcement, without the need of any vibration, whilst maintaining homogeneity. Self Compacting Concrete (SCC) URCC – NDDB – Odisha – Feb 2015 Self Compacting Concrete (SCC) Historical Background: The concept of SCC was first time proposed by Prof.Okamura and Prof.Ozawa in 1986 in Japan Self Compacting Concrete (SCC) The Concept was To achieve durability in concrete construction with the reduction in manual intervention Experience Fast paced construction lead to issues, mainly due to poor compaction in construction. Self Compacting Concrete (SCC) The first prototype was built in Japan in 1988 The World followed the foot steps of Japan in adopting SCC to aid concrete construction Ensuring durability of the structure was the main Objective Self Compacting Concrete (SCC) We too need to adopt this “Product-cum-Solution” AKA Filling Solution Self Compacting Concrete (SCC) SCC a unique product – ATTRIBUTES Fresh condition - Self-compacting by virtue of its flow and with optimal viscosity Early age – to remain uniform and free from initial defects such as segregation Hardened state – Form Durable structural mass to exceed performance requirements Self Compacting Concrete (SCC) SCC – Requirements in Fresh State Flowing Ability Passing Ability Segregation Resistance Viscosity Self Compacting Concrete (SCC) SCC – Test Methods SCC – Test Methods Slump-Flow Class Class Slump – Flow in mm SF 1 550 to 650 SF 2 660 to 750 SF 3 760 to 850 SCC – Test Methods Passing Ability class – L box Class Passing Ability PA 1 > 0.8 with 2 bars PA 1 > 0.8 with 3 bars SCC – Test Methods Passing Ability class – J-Ring – ASTM Class Passing Ability ASTM C-1621 Slump Flow difference Not more than 50mm SCC – Test Methods Viscosity class Class V-Funnel Time in seconds Conformity criteria VF 1 <8 +/- 3 VF 2 9 to 25 +/- 3 SCC in Critical Structures – A filling Solution Structures with congested reinforcement Structures have limited access Structures have unique shape Structures require good amount of resources for assurance Application & Case Studies Resource Optimization SCC – A filling Solution Pre cast Girders Southern Railways, Chennai - 2008 SCC – A filling Solution Pre cast Girders Southern Railways Gantry Girders for Fly -overs, Chennai Details CVC SCC Total Duration of Pour 4 Hours 2.0 Hours Volume of Pour 40 cum 40 cum 10 cum / hour 20 cum / hour Average Pour Rate Equipment requirement Man Power requirement 5 Needle & 7 Surface 15 Needle vibrator & Surface vibrator operators, Masons and helpers Nil 1 Mason for finishing Southern Railways, Chennai - 2008 SCC – A filling Solution Pre cast Girders 27.09.08 M55 81.5 59.01 59.77 59.53 59.44 67.77 68.25 68.48 68.17 15.11.08 M55 80.5 60.66 59.94 60.30 60.30 69.94 68.65 69.54 69.38 10.12.08 M55 81 60.44 58.88 59.64 59.65 68.13 66.89 65.69 66.90 02.01.08 M55 81 60.85 61.02 59.64 60.50 70.62 71.10 73.77 71.83 17.02.09 M55 81.5 59.42 60.40 63.28 61.03 69.95 71.50 72.04 71.17 07.03.09 M55 81 58.57 61.64 59.28 59.83 71.02 70.58 72.13 71.24 Mean Strength 69.78 Mean Strength 60.13 Southern Railways, Chennai - 2008 SCC – A filling Solution R.C.C Structural wall - Mivan TVH, Chennai SCC – A filling Solution R.C.C Structural wall - Mivan Flat Area 1200 Sft Details Volume of concrete 50 cum / flat Wall 27 cum + Slab 23 cum CVC SCC 50.00 cum Volume of Pour 50.0 cum 11 hours Total Duration of Pour Average Pour Rate 4.54 cum/hr Man Power 3 masons + 3 Vibrator operator + 9 Others Equipment Needle Vibrator 3 4.5 hours Requires high level of supervision TVH, Chennai 11.00 cum/hr cum 2 Masons + 4 others Checking fresh concrete properties @ ground is enough SCC – A filling Solution TVH, Chennai SCC – A filling Solution UltraTech Concrete, Bengaluru - 2009 SCC – A filling Solution KGISL, Coimbatore, 2009 Rebar Congestion & Accessibility SCC – A filling Solution TN PWD, Chennai – 2020-21 SCC – A filling Solution TN PWD, Chennai – 2020-21 SCC – A filling Solution URC, Ramanujan IT Park, Chennai SCC – A filling Solution SPCL - Fun City Mall, Coimbatore SCC – A filling Solution Project American Hotels Mysore Name of Customer BL Kashyap Consultant Synergy Concrete M35 – 358 cum SCC – A filling Solution Project Kandaya bhavan, Bangalore Name of Customer Devi Prasad construction Consultant Narayana Swamy and associates, Dr Viswanath of Torsteel & Srinivas and Khan (Architect) Concrete M35–190 cum–41m X 1.1m X 4.5m 38 MT of Main Reinforcement Steel Critical Shape SCC – A filling Solution Project DLF IT Park, Hyderabad Name of Customer DLF Concrete M50–120 cum + 5 X 2 Y- columns for Atrium Total height 26 M SCC for top 17 to 20 M Self Compacting Concrete BIAL – URCC, 2020-21 Do it right first time, all the time M75 Cube results Stress (Mpa) Average (Mpa) 77.2 76.2 77.9 90.9 102.2 94.6 99.3 95.9 97.6 82.6 79.4 77.7 95.0 90.6 96.0 95.1 106.8 106.8 ROB Pile Cap cast with M75 – BIAL - URC Age 77.1 7 Days 95.9 21 Days (100 mm) 97.6 28 Days (100mm) 79.9 7Days 93.9 14 Days (100mm) 102.9 40 Days (100mm) Do it right first time, all the time Precast Segment (SCC) – Curvilinear BIAL – URCC, 2020-21 Do it right first time, all the time Precast Segment (SCC) – Curvilinear SCC with High Early Strength BIAL – URCC, 2020-21 Self Compacting Concrete Shape, Access, Placing & Compaction constraints TN PWD, Chennai – 2020-21 SCC – A filling Solution Shell Structure TN PWD, Chennai – 2020-21 Self Compacting Concrete Shape, Access, Placing & Compaction constraints TN PWD, Chennai – 2020-21 Execution/Construction Effectiveness SCC – A filling Solution G K Shetty, Chennai- 2008 SCC – A filling Solution Landmark 81, HCMC SRDC, VIetnam 460m + SCC – A filling Solution Wall @ 400m + SRDC, VIetnam SCC – A filling Solution Slab @ 350m + SRDC, VIetnam SCC – A filling Solution M80 Transfer Slab Estancia IT Park, Zoho, Chennai Non-Critical Structures?? SCC – A filling Solution IIT Madras SCC – A filling Solution SCC – A filling Solution GK Shetty, Chennai – Aloft Hotel SCC – A filling Solution IIT Madras Can SCC be every day concrete? SCC – A filling Solution Challenges Need to be choosy in raw materials RMC has to keep other supply aside Purchase personnel Focused supply and execution Dedicated and Committed Team – Always overburdened Form work Noteworthy SCC – A filling Solution Coarse Aggregates tend to remain in the surface all along SCC – A filling Solution Coarse Aggregates tend to remain in the surface all along SCC – A filling Solution Coarse Aggregates tend to remain in the surface all along SCC – Form Work Pressure Even when SCC falls from height (accidently in this case) it does not segregate Mix Design Approach for SCC Achieving Strength is not an issue Achieving the Fresh Concrete Properties will be the objective (Easier to Say than get done) Mix Design Approach for SCC Higher binder content – OPC + Fly Ash – More than 450kg/cum Coarse Aggregate to Fine Aggregate ratio – 50:50 Fine Aggregates grading (Zone-II) and shape is the key PCE based Admixture to impart flow Viscosity Modifying Agent (VMA) to control segregation Mix Design Approach for SCC VMA Effect Mix Design Approach for SCC VMA Effect Advantages of SCC Placing of concrete with ease Achieving higher degree of compaction Faster construction rate Increased life of formworks Resource optimization Lesser pollution Enhancement in Quality of concrete ensuring durability of the structure FAQs Indian Standards? - Not available - Euro Guidelines & ASTM All Grades? - M40 and Above Type of Structures? - All type of Structures including Piles, Pile Caps, Diaphragm walls, Columns, Piers, Bridge Decks, etc Cost Increase? - Not in overall Cost , in Mix Cost - Mix cost increase is 2% < 10% Form Works? - Leak proof and to withstand Hydro-Static pressure on vertical sides
