This study aims to verify the proposed method for improving the consolidation coefficient (cv), reducing settlement and swelling, and investigating the influence of added waste ceramic powder (WCP) on clay soil. The experimental work involved conducting consolidation tests on clay soil using three samples. The soil was treated by adding three percentages of WCP (10%, 20% and 30%). The results showed that an increase in the ratio of WCP addition improved the soil, with the coefficient of volume change (av) showing a 59.5% improvement. Using 10% WCP improved soil settlement by 26.21%, and the consolidation coefficient (cv) was reduced by 21.01%. Additionally, using 10% WCP reduced swelling by 46.9280%. These improvements indicate that WCP can be used as a stabilisation material to mitigate volume changes and improve the consolidation processes of subgrade soils when used in weak soils as foundation materials.