砂质泥岩风化土的动力特性试验研究

摘要

Based on the actual situation of engineering,the weathered sandy mudstone soil beneath a construction site is studied.Through dynamic triaxial test,dynamic characteristics of the wethered soil under 4 selected confining stresses are studied;the impacts of confining stresses on it are con-cluded.In the range of analyzed confining stress,the dynamic stress-strain backbone curve and dy-namic modulus curve increase as long as confining stress increase;Power correlations between its two parameters containing the maximum dynamic modulus and the confining stress are obtained, the maximum dynamic modulus of the weathered soil increases as long as the confining stress in-crease by exponential form;The damping ratio reduced with confining pressure increases,and the magnitude reduced is increses in first and then decreases.The dynamic shear modulus ratio curves are normalized well under diferent confining stress conditions.%以某工程场地下伏砂质泥岩风化土为研究对象，结合工程实际情况，通过循环振动三轴试验，对风化土在选定的4组固结围压状态下表现出来的动力特性进行了研究，得出了固结围压的变化对其产生的影响。在研究的固结围压范围内：固结围压对动应力-应变骨干曲线及动弹模量曲线的影响较大，骨干曲线与动弹模量曲线均随固结围压的增大而提高；最大动弹模量与固结围压间具有良好地幂函数关系，并且幂指数随着固结围压的增大呈现增长；固结围压的增大阻尼比随着减小，且减小的幅度先增大后减小；动剪模量比曲线在不同的固结围压状态下表现出了良好地归一化特性。