Ashcrete mixes were prepared by replacing coarse aggregate with bottom ash and a portion of cement with fly ash. Replacement of conventional raw materials is performed in high volumes to reduce the carbon footprint of the mix. Microencapsulated Phase Change Materials (MPCMs) were added to the mixes to enhance their heat-retaining capacity. The mixes contained Cement (C), Fly ash (FA), Bottom ash (BA), Sand (S), and Microencapsulated phase change materials: MPCM37D (P) and MPCM43D (Q).

The tests shown in the flow chart were performed to achieve optimal packing density of the mixes. Subsequently, the performance evaluation of the mixes is performed.

An in-house designed experimental setup was developed for testing the concrete slab specimens for their heat-retaining efficiency. An oven equipped with air blower was used as the heat source and its temperature was manually controlled using a temperature regulator. The slab to be tested was sealed from all lateral directions to prevent any heat exchange between the slab and the surroundings through the lateral sides. Thermocouples were used to measure the slab temperature on the oven side and an infrared thermometer was used to measure the temperature on the exposed side. A schematic diagram and a photograph of the experimental setup are shown below.