轨道交通振动作用引起的土单元应力路径特征及其在室内试验中的模拟  

The characteristics and laboratory test simulation of stress path induced by traffic loading

作　　者：陈国兴[1] 潘华[1] 

机构地区：[1]南京工业大学岩土工程研究所,江苏南京210009

出　　处：《土木工程学报》2010年第S2期340-345,共6页China Civil Engineering Journal

基　　金：江苏省自然科学基金(BK2008368);中国地震局地震工程与工程振动开放实验室基金(2007A02);江苏省研究生科研创新计划项目(CX10B_170Z)

摘　　要：为了实现在室内试验中模拟轨道交通振动作用下土单元应力路径特征的加载方法,以均布移动荷载和单轮移动荷载为例,分析路基中土单元的应力状态。发现两种简化的轨道交通振动作用下路基土单元呈现出相似的应力状态:在荷载从左到右的移动过程中,主应力方向角发生了180°的变化,主应力差连续变化;路基中土体单元的应力状态,由最初的单剪模式变化到三轴剪切模式,最终又回到单剪模式;在应力坐标体系中的应力路径为"苹果状"。利用动态空心圆柱仪可以自定义加载函数的特点,在室内试验中比较理想地实现了轨道交通振动作用下路基土单元"苹果状"应力路径的模拟过程。In order to put forward a laboratory technique for simulating the stress path under traffic loading,one uniform moving load and one single wheel load are taken as examples to analyze the characteristics of stress states.Similar stress states that induced by the two simplified traffic loadings were observed,the principal stress axes rotate 180°,the differences of principal stresses change continuously,the stress state changes from the pure shear to triaxial shear and back to pure shear,the stress paths are 'apple-shaped' curves in the coordinate system.On the base of the properties including custom loading function of hollow cylinder apparatus,a successful method was proposed to simulate the stress path that induced by traffic loading.

关 键 词：轨道交通振动作用 应力路径 动态空心圆柱仪 

分 类 号：TU435[建筑科学—岩土工程]