Effects of coal-bearing metakaolin on the compressive strength and permeability of cemented silty soil and mechanisms

The effects of coal-bearing metakaolin (CMK) on mechanisms, unconfined compressive strength (UCS) and impermeability of cemented silty soil were experimentally investigated in this study. The hydration, pore structure and microstructure of cemented silty soil were improved by incorporating moderate amounts of CMK, according to X-ray diffraction, mercury intrusion porosimetry, and scanning electron microscopy. The UCS and impermeability of cemented silty soil were significantly improved, which is consistent with the microstructural results. However, cemented silty soil with excessive amounts of CMK exhibited inferior properties. The optimum mass ratio of CMK to cement was between 1:6.5 and 1:4.