Papers by Author: Xiu Mei Zhong

Abstract: Environment pollution and exhaustion of mineral resources aroused strongly research and development of fly ash utilization. As a kind of foundation treatment method, improved by fly ash is more and more used in highway, railway roadbed construction. With the increase of speed of vehicles and vehicle load, the influence of dynamic load on the subgrade has caused people's concern. In this paper, based on fly ash modified loess, dynamic property of modified fly ash loess is discussed through the dynamic triaxial test of the unsaturation disturbed loess. The effect of the dynamic elastic modulus and the damping ratio with different amount of fly ash loess is studied. The results show that the difference of dynamic properties in dynamic load and static load is large. It mainly presents the hysteresis quality and nonlinear relationship between dynamic stress and dynamic strain. And the dynamic elasticity modulus increases with fly ash mixed amount.

Abstract: The structural property is an important influence factor in loess liquefaction, which contains the interaction between the soil granules. According to study by Gao, the loess could be divided into three types as weak cemented loess, half cemented loess and cemented loess based on the grain composition, the consolidation and the weather conditions of the loess when it formed. In this paper, based on microstructure test and dynamic triaxial test of the loess from the Loess Plateau region, liquefaction properties of structural loess was analyzed. The results show that: (1) the structural strength of loess of weak cementing type, half cementing type and cementing type increases in order, and so does the liquefaction strength, (2) the change mechanism of different structural loess’s dynamic strain during liquefying is different, (3) the change of saturation loess’s pore water pressure during liquefying is related to the type of pore and the structural strength.