Experimental study on disintegration of loess improved by cement

Loess has porous metastable structure and water sensitivity, and is prone to collapse when it encounters water. The disintegration of loess is one of the main factors that promote soil erosion, collapse, landslide and other geological disasters in the Loess Plateau. As a low cost and convenient material, cement improved loess (CIL) is widely used in loess foundation and slope engineering, but there are few researches on its anti-disintegration. The disintegration behavior of loess before and after the improvement was analyzed through the laboratory disintegration test and scanning electron microsope (SEM) test under the condition of CIL and different content, and the improvement effect and mechanism of cement on loess disintegration were explored. The results show that cement can greatly improve the anti-disintegration ability of loess. At low content, CIL still has a complete disintegration process, but cement can fill the intergranular pores and hinder water transport. Meanwhile, cement hydration and its interaction with loess particles can enhance intergranular cementation, thus delaying the disintegration process of loess. With the increase of cement content, the anti-disintegration effect is more obvious, and the cumulative disintegration component is almost 0. The minimum cement content of soil sample without disintegration is 3%. The results are of great significance to the study of erosion resistance of loess and the design of disaster prevention engineering.