Self-comapcting concrete final year project
- 1. EXPERIMENTAL INVESTIGATION OF EFFECT OF STEEL FIBERS IN SELF COMPACTING CONCRETE Prepared by:- Sankpal Mihir Sunil Joshi Omkar Umesh Mozar Varsha Chandrakant Guided by:- Prof.P.S.Matkar Department of Civil Engineering, Yashoda Technical Campus
- 2. 1 Introduction What is SCC…………? Compacts by its self weight. Has ability to fill the formwork with dense reinforcement. Relatively high powder content than ordinary concrete. Reduces noise pollution. Usefulness in specially earthquake resistant structure. To achieve durable concrete structure. High compressive strength, stiffness, low thermal and electrical conductivity.
- 3. 1.1 What brings the necessity of steel fibers in SCC………? Less ductility(brittle). Weak in tension. Less post crack resistance. Less resistance to shrinkage and creep strain. To improve first crack load, energy absorption capacity. To improve toughness, flexural strength,impact strength.
- 4. 1.2 Objectives To evaluate the effect of steel fibers on the workability of SCC. To assess the impact of steel fibers on the compressive strength of SCC. To determine the influence of steel fibers on the flexural strength and toughness of SCC. To analyze the durability characteristics of SCC containing steel fibers.
- 5. 2.Literature Survey Okamura et al. Self compacting concrete (SCC) is a highly flowable and can spread in place under its own weight and achieve good consolidation in the absence of vibration without having the defects due to segregation and bleeding. Grunewald et al. investigated the effect of type and content of fibers on the characteristics of self-compacting concrete in order to optimize the mixture composition. Fibers are able to bridge cracks and to improve the ductility of otherwise brittle cementitious materials.
- 6. Eduardo et al. suggested that the behavior of SCC as a structural material can be improved if adequate steel fiber reinforcement is added to SCC mix composition. In fact, the fiber-reinforcement mechanisms can convert the brittle behavior of this cement-based material into a pseudo ductile behavior up to a crack width that is acceptable under the structural design point of view. Joaquim Barros et al. shown when the benefits of self- compacting concrete (SCC) are added to those resulting from the addition of discrete steel fibers to cement based materials, a high performance material, designated as steel fiber-reinforced self-compacting concrete (SFRSCC), is obtained.
- 7. 3.Methodology 1.Filling ability - Slump flow by Abrams cone - V-funnel 2.Passing ability - L-Box
- 8. 3.2 Slump cone test Apparatus required for slump flow test
- 9. Slump cone test Experimental setup Slump cone test – Filling ability T50cm slump flow – 2 to 5sec
- 10. 3.3 V-Funnel test apparatus V-funnel T – Filling ability - 8 to 12sec. V-funnel at T5min – Segregation resistance - 0 to 3sec.
- 11. 3.4 L-Box apparatus L-box - Passing ability - H2/H1 – 0.8 to 1
- 12. L-Box apparatus used in lab
- 13. 4.Final mix proportion Cementitious material = 398 kg/m3 Fly Ash = 10% (39.8 kg/m3 ) Cement = 358.2 kg/m3 C.A.20 mm = 497.75 kg/m3 C.A.10 mm = 407.25 kg/m3 F.A = 900 kg/m3 Water = 191 kg/m3 Superplasticiser = 1% (3.98 kg/m3 ) Steel fiber = 1%(3.98 kg/m3 ) = 2%(7.96 kg/m3 ) = 3%(11.94 kg/m3 ) Viscosity Modifying Agent = 0.5%(1.99 kg/m3 ) Slump flow = 640 mm
- 14. 5.1 Fresh mix properties Concrete type Slump flow (mm) T500(Sec) L-Box V-Funnel (Sec) Blocking Ratio (H2/H1) SCC 638 2.89 0.94 7.67 SFCC1 620 3.76 0.91 8.01 SFSCC2 597 4.9 0.88 10.12 SFSCC3 589 5.3 0.84 12.34 5.Results
- 15. 5.2 Hardened concrete properties Concrete type Compressive strength (Mpa) Splitting tensile strength (Mpa) Flexural strength (Mpa) NC 16.45 2.39 1.8 SCC 17.94 2.41 2.21 SFSCC1 17.35 2.48 3.31 SFSCC2 16.26 2.52 6.36 SFSCC3 16.10 2.62 9.94 Hardened properties at concrete age of 7 days
- 16. Slump flow achieved for final mix
- 17. Specimens of beams, cubes & cylinders
- 18. 4.Conclusion The slump flow for plain SCC was 640 mm and as fiber content is increased, slump flow i.e. workability decreased and the time increased for mix proportion flow ability. The mix proportion satisfies the filling ability test in V-funnel but failed in segregation resistance test. Steel fibers significantly enhanced the flexural strength of SCC, with a progressive increase from SFSCC1 to SFSCC3, demonstrating improved toughness.
- 19. 4.3 Application Construction of runway slabs, highway paving and industrial floors. Repairs and new construction on major dams and other hydraulic structures to provide resistance to cavitation and severe erosion. Repairs and rehabilitation of marine structures. Tunnel lining.
- 20. 5 References 1) A. Orbe,J. Cuadrado ,R. Losada,E. Rojí “Framework for the design and analysis of steel fiber reinforced self-compacting concrete structures”, Construction and Building Materials 35, 2012, pp. 676–686. 2) Anant Patel, Prashant Bhuva, Elizabeth George, Darshana Bhatt “Compressive Strength and Modulus of Elasticity of Self-Compacting Concrete”,National Conference on Recent Trends in Engineering & Technology, May 2011, pp.1-4. 3) B H V Pai, Sujith Kumar C.P “Experimental study on steel fiber reinforced self-compacting concrete with silica fume as filler material”, 34th Conference on our world in concrete & structures, August 2009, pp.16-18. 4) Buquan Miao, Jenn-Chuan Chern and Chen-An Yang “Influences of Fiber Content on Properties of Self-Compacting Steel Fiber Reinforced Concrete”, Journal of the Chinese Institute of Engineers, Vol. 26, No. 4, 2003, pp. 523-530. 5) E.B. Pereira, J.A.O. Barros, V.M.C.F. Cunha and S.P.F. Santos “Compression and bending behavior of steel fiber reinforced self-compacting concrete” University of Minho, Portugal, April 2008.
- 21. 6) Eduardo N.B., Pereira, Joaquim A.O., Barros and Aires Cameos, “Steel Fiber Reinforced Self Compacting Concrete; Experimental Research and Numerical Simulation, Journal of Structural Engineering”, ASCE, Auguest-2008, pp.1310-1315. 7) EFNARC, “The European Guidelines for Self Compacting Concrete Specification, Production and Use”, May 2002. 8) Hajime Okamura and Masahiro Ouchi, “Self Compacting Concrete”, Journal of Advanced Concrete Technology Vol. 1, No. 1, April 2003, pp. 5-15. 9) Hamid R. Salehian and J. A. O. Barros “Steel fiber reinforced self-compacting cementitious composite– tensile and flexural response” Department of Civil Engineering, University of Minho,2010 10) I.S.12269 - 1987, “Specification for 53 Grade Ordinary Portland Cement”, Bureau of Indian Standard, New Delhi, 1988.