Optimization of Calcined Termite-Mound Material (CTM) Mortar and Concrete using Response Surfaces Methodology

Abstract

This study is aimed at the optimization of calcined termite mound material incorporated in mortar and concrete using Response Surfaces Methodology (RSM). The calcined termite mound material substituting cement in mortar and concrete varied from 5 to 15% at interval of 5% in mortar and concrete. Sikament NN was added from 1.0 to 3.0 at interval of 1.0. Test conducted on mortar were: consistency and setting times. For concrete, specimens were cast and tested to failure for all the mixes for curing periods of 3, 7, 28, 60 and 90 days. Modelling and optimization were carried out using Design-Expert software version 11.0 with CTM (5%, 10% and 15%) and Sikament NN (1.0%, 2.0% and 3.0%) levels taking as the input variables. The output responses for mortar were consistency, setting times, on concrete compressive strength test after 3, 7, 28, 60 and 90days curing. Comparison was made to the performance of CTM blended mortar and concrete with controls mortar and concrete in terms of consistency, setting times and in concrete compressive strengths. Results from analysis of variance (ANOVA) indicate that both CTM and Sikament are influential variable in the developed models and all the RSM models are statistically significant in all the factor levels. The optimum mix for mortar was obtained by addition of 2.09 % Sikament NN and 5% CTM replacement with 0.871 desirability. In concrete, 2.05 % Sikament NN and 5% CTM replacement with desirability 0.871 was the optimum.