Strength prediction of sustainable concrete incorporating rice husk ash by using regression technique

Abstract

In the present scenario, agricultural wastes are used as good replacement material in the construction industry. Rice husk ash (RHa) is used as partial replacement material in the concrete mix and act as pozzolanic materials (PM) for the growth of blended cement. Concrete was prepared by replacing cement with RHa in varying proportions 5%, 10%, 15%, 20%, and 25% by weight of cement) in dry condition. Towards this objective, experiments were carried out in two phases. In the first phase, the strength property of the RHa blended concrete mix was determined separately to get the optimum replacement level and the test includes compressive strength (CS) was performed, and results are presented. Test results reveal that the cement replaced by 10 % RHa enhance the strength of the concrete mix. In the second phase, after performing the experimental tests, mathematical equations were developed using regression analysis to determine the predicted CS. For validation, the correlation between the experimental and predicted CS with time is observed. Results show the 10RHa sample was the best fit model with the highest correlation coefficient of correlation R2 (99.3%). To perform the studies using SEM and EDS along with elemental maps of concrete prepared at optimum conditions to observe the variations in micro structure. Therefore, it can be concluded that RHa in concrete are responsible for enhancing the performance of concrete strength.