Reclaimed brick masonry makes up a noteworthy portion of construction and demolition waste (CDW), totaling approximately 31%, even exceeding concrete waste. This study proposes using reclaimed brick masonry to enhance the micro- and macro-properties of clayey soil. Extensive laboratory testing was conducted to evaluate the performance of reclaimed brick powder (BP) along with 5% cement content. The cement was used to generate chemical bonds with BP and soil grains. Micro-testing like XRF, XRD, EDAX, and SEM analyses confirmed the formation of CSH and CAH compounds which strengthened soil structure and enhanced its brittleness. However, after 10% BP, the addition of coarser grains converted the soil structure from dense to porous. Macro-properties assessment confirmed that 10% BP with 5% cement content is an optimum combination for selected soil. The addition of BP reduces the required amount of cement for soil stabilization, making it an eco-friendlier solution. The addition of the optimum combination decreased the wL, IP, FSI, wopt, and Cc and increased the gamma dmax, qu, CBR value, and sigma y significantly. It is also confirmed by the specimen's failure morphology analysis that BP with cement in clayey soil curtailed cement generated brittleness and enhanced ductility.

Micaceous residual soil (MRS), a marginal geomaterial commonly found in tropical regions, is often used in lowgrade construction projects due to budget constraints. However, little is currently known about its geotechnical properties, especially its long-term environmental response and microstructural variations. Investigated here is how mica content and climate-induced wetting-drying (WD) cycles affect the physical and mechanical properties of MRS. Reconstituted MRS samples with varying mica contents were prepared by mixing muscovite powder with plain residual soil, from which the original mica was removed. These samples were subjected to WD cycles to simulate tropical climate conditions. Geotechnical properties and microstructural changes were analyzed through systematic experimental tests and microscopic observations. The degradation observed during the WD cycles included crack propagation, volumetric swelling, reduced strength, and increased disintegration, all of which were positively correlated with mica content. Notably, for MRS with high mica content, the WD cycles ameliorated the soil brittleness, altering previous perceptions of uniformly low performance for MRS. The effect of mica on MRS under long-term environmental changes is attributed to both the inherent properties of mica and the particle packing structure in the soil. This study enhances the understanding of MRS behavior in tropical climate and provides technical recommendations for further improvement and effective application of this marginal geomaterial.