Mechanical Properties of Clays Stabilized with Glass Powder and Silica Fume

Abstract

The main purpose of improving the natural soils is to provide them with the capability to carry loads from buildings, foundations, and earth structures, and to make them resilient against disasters caused by excessive and abnormal loading, emerging climates, and natural hazards such as earthquakes and landslides. Clay soils in particular are soils that are susceptible to subsidence, so the engineering properties of these soils need to be improved. Universally common binders for improving the engineering properties of clay soils cement, lime, calcium-based stabilizers, fibers, and upcycled plastic wastes. Glass powder (GP) has recently gained interest as an alternative stabilizer for clay soils. In this study, the strength and microstructural properties of clayey soil mixed with GP and silica fume (SF) are examined. To this end, clays are mixed with 10, 15, and 20 wt.% glass powder and 10 wt.% silica fume and cured up to 7 and 28 days. Samples are compacted at optimum water contents to maximum density and are subjected to compression and direct shear tests alongside microstructural analysis. Findings suggest that a combination of 15% GP and 10% SF provides the optimum test results. Overall mechanical behavior of testing samples improved with increasing GP content up to the testing 15% threshold. In the optimum design mixture, a 390% increase in compressive strength and a 322% increase in direct shear strength were obtained compared to the control samples. SEM analysis also supports results that show improved pore structure.