不同含水量下原状黄土动强度和震陷的试验研究

DYNAMIC SHEAR STRENGTH AND SEISMIC SUBSIDENCE OF INTACT LOESS WITH DIFFERENT WATER CONTENTS FROM DYNAMIC TRIAXIAL TESTING

对原状黄土进行动三轴试验,探讨了黄土的动强度和震陷随含水量的变化规律。试验结果表明,塑限含水量可作为黄土动强度和震陷的界限含水量,小于塑限的含水量变化对震陷临界动应力和动粘聚力的影响非常显著,大于塑限的含水量变化对其影响微弱,而动摩擦角不受含水量的影响。通过对震陷曲线的定量分析,说明有必要对黄土的震陷性进行分类。

Dynamic properties of intact loess are studied through laboratory dynamic triaxial tests; and variations with water contents are discussed of its dynamic shear strength and seismic subsidence. Test results show that water content has a major influence on the dynamic properties of intact loess. When taking plastic limit as a bound, variation of water content smaller than plastic limit has major influence on dynamic cohesion and seismic subsidence critical stress; while variation of water content greater than plastic limit has very minor influence on them. Little influence has variation of water content on dynamic friction angle. Through regression analysis of seismic subsidence curves, it is showed that seismic subsidence needs to be considered into loess classification.