1. Nanjing Hydraulic Research Institute, Nanjing 210029, China; 2. College of Water Conservancy and Hydropower, Hohai University, Nanjing 210024, China
Abstract：The relatively low early strength and significant cracks are the common issues for the cementitious materials-stabilized soil (cemented soil). To remedy its defects, novel ionic soil stabilizers (ISS) with dosages from 1/300 to 1/50 of water content volume of the cemented soil are applied. Through the tests on unconfined compressive strength and volume chemical shrinkage, the modification feasibility of ISS application is verified. Through the characterization and analyses of the surface adsorption behaviors, phase evolution and micro-structure, the modification mechanisms of ISS on cemented soil are systematically studied. The results indicate that the ISS molecules adsorb on the compositions of cemented soil selectively. After the ISS addition, the system dispersion is enhanced, the water combination capacity of soil minerals is reduced, thus accelerating the formation of hydration products, benefiting the pore distribution and increasing the volume chemical shrinkage. The optimum dosage of this study is 1/150, and the excessive addition will retard the modification effects but reduce the chemical shrinkage. The results can be used as a reference for the modification of cemented soil with ISS.
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