Abstract:
This study investigates the potential of Waste Marble Dust (WMD) and fine Cinder
Gravel (CG) to enhance the engineering properties of expansive soils, which are prone
to volume changes due to moisture fluctuations. The research aimed to stabilize
expansive soils, classified as A-7-6(37) in the AASHTO system and CH in the USCS
system, for use as sub-grade materials in road construction. Mechanical stabilization
technique was used in this study. Soil material is dried in air and mixed with 8%, 12%,
16%, and 24% of CG and MD. The key findings include; Plasticity Index reduced from
34.09% to 10.28%, Free Swell Index decreased from 81.8% to 36.4%, Optimum
Moisture Content decreased from 24.02% to 14.00%, Maximum Dry Density increased
from 14.22 kN/m³ to 16.19 kN/m³, California Bearing Ratio (CBR) increased from
1.00% to 22.69% and Unconfined Compressive Strength (UCS) increased from 112.9
kPa to 311.7 kPa. Optimal stabilization was achieved at a 16% replacement of both
WMD and CG, improving the soil's strength significantly. This study concludes that
WMD and CG are effective stabilizers for expansive soils, meeting the requirements
for sub-grade material in road construction and offering improved durability and
performance.
