Experimental Investigation on the Strength and Microscopic Properties of Cement-Stabilized Aeolian Sand

Abstract

Aeolian sand widely exists in the desert of western China. The reinforcement of aeolian sand is of considerable significance to the construction of transmission lines in the desert. In order to study the impact of different cement contents and moisture content on the performance of the cement-stabilized aeolian sand, 18 types of samples of aeolian sand with different water and cement contents were prepared. The confined and unconfined compression tests of the aeolian sand samples were conducted on the TSZ series automatic triaxial instrument. The microscopic observation methods and macroscopic strength tests were adopted to understand the cement-stabilized mechanism. The results of the triaxial test manifest that both the moisture content and the cement content affect the stress-strain behavior of the cement-stabilized aeolian sand. The cement-stabilized effect on aeolian sand can be estimated by the degree of hydration reaction. Microscopic test results show that as the cement content increases, the pores in the microstructure decrease, and some crystalline substances appear. The content of calcium silicate hydrate (C-S-H), which is one of the hydration products, is measured by the X-ray diffraction method. The results indicate that the solidification effect of cement is related to the C-S-H percentage. For 3% water content, the percentage of C-S-H goes up first with the increase of cement content and then gradually decreases at the cement content of 6%. When the water content goes up to 5% and 7%, it is found that the production of C-S-H gel increases with cement content.