Feasibility study of utilisation of ferrochrome slag as fine aggregate and rice husk ash as cement replacement for developing sustainable concrete

Utilisation of ferrochrome slag as partial substitution of the fine aggregates and incorporation of rice husk ash (RHA) in place of cement has been carried out in this study to generate a sustainable concrete. For this, workability, compressive strength (CS), split tensile strength (STS), flexural strength (FS), rebound number (RN), ultrasonic pulse velocity (UPV), water absorption (WA), density and volume of voids (VV) of 12 numbers of concrete mixes made with 0%, 10%, and 20% ferrochrome slag fine aggregates (FSA) and 0%, 10%, 15% and 20% RHA have been investigated. The outcomes of this investigation depicts that all the mixes designed in this study incorporating (FSFA) and RHA has satisfied the workability requirements of concrete to be used for normal construction work. Furthermore, a substantial reduction in CS has been noted in the early days of the mixes made with higher quantity of RHA and FSFA; however, improvement in strength parameters has been seen in later days. The results of STS, FS, RN and UPV of mixes follow a similar trend to the CS for all mixes examined in the current investigation. Overall, the outcomes of this study conclude that the concrete characteristics considered for of this work are not significantly influenced with the inclusion of FSFA in place of natural sand. However, the reduction in concrete behaviour has been detected with the use of higher RHA (%). Further, the present study recommends for the utilisation of 10%–15% RHA and 10% FSFA in concrete for various applications.