Effect of Fineness and Ash Replacement Rate on Mortar Physical Properties: An Experimental Investigation

The construction industry is a large consumer of cement which is used in concrete and mortar manufacture. Cement substitution would reduce its economic and environmental cost. This work is part of the local materials development such as cement and residual ash from thermal power plants. Our objective is to study the effect of ash fineness and replacement rate on the thermomechanical characteristics of mortar. For this reason, the ash was ground into two different fineness values of 4500 cm2/g and 6500 cm2/g and used as replacement rate ranging from 10 up to 50% by weight of cement. In a first step, the thermal properties of ash mortars have been experimentally determined in terms of thermal conductivity and diffusivity using the box method, subsequently, thermomechanical characterizations were performed using the H10KL bench to estimate the ash mortars mechanical parameters. Test results show that the use of ash in the mortar resulted in a significant improvement in thermomechanical properties and a substantial decrease in water absorption. This subsequently contributes to the reduction of building energy consumption, CO2 emissions in the atmosphere and annual quantities of ash produced by thermal power stations.