Gravimetric weight loss of steel in self-compacting concrete blended with wood ash and silica fume.

Abstract

The present research work deals with the development of self-compacting concrete (SCC) containing wood ash (WA), silica fume (SF) and their combination (1:1 ratio). Several research studies have reported on the performance of WA and SF-blended SCC. However, very limited information is available on the effects of silica dioxide (SiO2) and subsequent formation of calcium-silicate-hydrate (C-S-H) gel and its benefit on the strength and durability enhancement of self-compacting concrete. In this work, wood ash (WA) and silica fume (SF) were used as cement replacement materials, and studies were carried out on the chemical composition and its contribution in the strength development of SCC. Compressive strength, ultrasonic pulse velocity and dynamic modulus of elasticity have been increased when the cement is replaced with WA, SF and WA + SF content up to 10%, 6% and 30 + 8% respectively than normal SCC. From the EDAX analysis, Ca content in the mixes, NSCC mix has higher Ca content (52.04%) whereas 10% WA SCC, 6% SF and 30% WA + 6% SF SCC has 41.78%, 33.64% and 28.77% respectively. Similarly, SiO2 content 6% SF-blended SCC has higher value (38.03%) than other mixes. As 6% SF-blended SCC has a higher value of SiO2, it gives the higher compressive strength and UPV values because of high reactivity and subsequent formation of C-S-H gel.