Investigation of properties of cement mortar incorporating pond ash – An environmental sustainable material

Abstract

Abstract This study focused on the use of coal-based pond ash from Bhusawal thermal power plant (India) as a fine aggregate and cement replacement in cement mortar at a replacement percentage from 0% to 100%. Two series of cement mortar mixes were prepared. Experimental analysis based on properties of mortar such as compressive strength, flexural strength, workability, setting time, bulk densities by addition of pond ash in a mortar. Investigation on the physical properties of mortar incorporating pond ash through X-ray diffraction (XRD), X-ray Fluorescence (XRF), and scanning electron microscope (SEM) with an energy dispersive X-ray analysis system (SEM-EDX) was also done to study microstructure analysis and to correlate these physical properties with mechanical properties of cement mortar. The presence of pond ash in series-I affects the strength positively with inclusion up to 40% replaced with sand in mortar series-I. With the increased content of pond ash replacement beyond 10% with cement, the strength of mortar seems to be reduced. The SEM results showed growth of dense crystalline plate-like structure and give evidence of portlandite leads to solidification of mortar mass when pond ash was replaced with sand in the mortar. The presence of portlandite through SEM represents the solidification and densification of mortar mass. The addition of pond ash leads to an increase in the amount of CSH gel in the mortar. This may be the reason for the improved performance of mortar up to certain level of replacements.