【摘要】 采用中型三轴仪对饱和砂砾料试样在循环荷载作用下液化后再进行静力加载试验,系统地研究相对密度、初始有效固结压力、液化安全率和抗液化应力比等主要因素对液化后砂砾料试样静力再加载变形与强度特性的影响。提出确定液化后静载试验条件下应力-应变曲线特征物理量的确定方法,避免了模型参数确定的随意性。基于试验结果建立了能综合考虑相对密度、初始固结压力、液化安全率和抗液化应力比的饱和砂砾料液化后静力再加载应力-应变发展过程的模型,并通过试验对模型进行了验证。更多还原

【Abstract】 Using a intermediate-scale dynamic triaxial apparatus(specimen size 200×510) ,laboratory tests on the post-liquefaction sand-gravel composites were performed to investigate the effects of the relative density,initial consolidation pressure,liquefaction safety and cyclic stress ratio. The results show that the reloading behavior of the liquefied sand-gravel specimens is distinctly different from those without dynamic loading. The reloading stress-strain curve is approximately composed of three parts,the stiffness-recovering part,the stiffness-stabilizing part and the plastic flow part. A method is given to determine the characteristic parameter values,which avoids the uncertainty of the method by Yasuda and assures the accuracy of the parameter analysis. A tri-linear static stress-strain model of liquefied sand-gravel composites is established,in which the initial consolidation pressure,liquefaction safety and cyclic stress ratio can be considered synthetically.更多还原