STUDY ON INTERACTION MECHANISM BETWEEN CLAY MINERALS AND ALKALI ACTIVATED GEOPOLYMERS

Abstract

As the most active component of particles, clay minerals play an important role in the physical and mechanical properties of soil, such as liquid plasticity, strength and expansibility. One of the core problems of soil solidification is the use of suitable curing agents to solidify the clay minerals. This paper carries out scanning electron microscopy(SEM), Fourier infrared spectroscopy(FTIR), X-ray diffraction(XRD), and X-ray photoelectron spectroscopy(XPS), studies the microstructure, material composition and physicochemical reaction process of clay minerals solidified by alkali-activated geopolymers with different alkali dosages, and discussed the interaction mechanism of alkali-activated geopolymers and clay minerals. The results show that Alkali activated geopolymers can solidify clay minerals well. The clay minerals are transformed from loose particles to bulky dense structure after solidified by alkali-activated geopolymers. With the alkali dosage of geopolymers increases, the electronic binding energy of Si, Al, and Ca elements decreases. The diffraction peak of montmorillonite shifts to the right(001) at a diffraction angle of about 5°, and the interlayer distance is decreased. The absorbed water content and hydrophilic capacity of montmorillonite are decreased, and the mineral activity is limited.