Effect of Silica Fume in High-performance Selfcompacting Concrete with Conplast SP430

Abstract

Concrete is a construction material used worldwide since ages. Self-compacting concrete is that type of concrete which is firstly being developed in Japan in early 1990s and is capable to flow under its own weight and completely fill the formwork, without vibration effect, and cohesive enough to be handled without segregation and bleeding. Self-compacting concrete is known to be new class of high-performance concrete which is used to facilitate and accelerate concrete placement without mitigating in-situ properties and durability. The present investigation aims to develop highperformance self-compacting concrete of grade M40 as per IS 10262:2019. To prepare SCC mix Conplast SP430 as a chemical admixtures and silica fume as a mineral admixture were used. As per IS 10262:2019 tests which should be performed on fresh self-compacting concrete are filling ability, passing ability, segregation resistance, and viscosity. Total 10th trials being prepared out of 10th trials 8th trials got failed but in 9th trial our all-fresh self-compacting concrete tests got passed. Then in 9th trial, we casted 3 cubes for compressive strength test but due to late demoulding of cubes we did not get required strength then in 10th trial all other things kept same but 1% by mass of cementitious material calcium chloride has been added for early demoulding of cubes. Then to check hardened properties of SCC 12 cubes, beams and cylinder specimens were being casted and 6 cubes for durability were also being casted out of which 3 cubes were kept in normal water and other 3 cubes were kept in 3.5% NaCl solution in water tank for 60 days.

Keywords: High-performance, self-compacting concrete, segregation resistance, viscosity.