Value added utilization of industrial by-products in producing high performance concrete

Abstract

The objective of this study is to evaluate the effect of various industrial by-products on the fresh and hardened properties of high-performance concrete with micro structural analysis on mechanical characteristics and durability characteristics. High performance concrete (HPC) is developed gradually over the last 15 years with respect to production of concrete with higher and higher strength. It is defined as the concrete with improved constructability, improved durability and improved mechanical properties. The experimental investigation on the effective use of silica fume, bottom ash & steel slag aggregate as a replacement of cement, fine aggregate & coarse aggregate on the properties of high-performance concrete. An effort has been made to concentrate on the mineral admixture of silica fume towards their pozzolanic reaction and industrial by-product of bottom ash and steel slag towards their hydration reaction can be contributed towards their strength and durability properties. The durability studies such as acid resistance, salt resistance and RCPT were conducted. There was a total of 15 mixes created with different material contents. Out of 14 were HPC mixes and 1 were conventional concrete mixes by many trial mixes. Finally, strength has enhanced with the mix of silica fume can replaced by cement with 5% and bottom ash and steel slag can be replaced by fine and coarse aggregate with 10% can be achieved higher strength when compared with other percentage of mixes. The combination mixes can be classified as binary and ternary mixes. Binary mixes involved combinations of silica fume and bottom ash (SF+BA), silica fume and steel slag aggregate (SF+SSA), bottom ash and steel slag aggregate (BA+SSA) and Ternary mixes involved combination of three materials such as silica fume, bottom ash and steel slag aggregate (SF+BA+SSA) in High performance concrete. The investigation revealed that the combined use of silica fume, bottom ash and steel slag aggregate improved the mechanical properties of HPC and thus there 3 materials may use as a partial replacement material in making HPC. In addition, scanning electron microscope and EDAX were studied. Microstructure constitutes the nature of the solid portion and nonsolid portion. Some factors of micro structural features are physical and chemical nature of the cement, type and amount of admixture etc. From the experimental investigation, it was observed that mineral admixture of silica fume and industrial by-products of bottom ash & steel slag aggregate plays a vital role in improving the strength and durability parameter itself.