交通荷载下层状路基动附加应力的弹性计算模型  

ELASTIC CALCULATION MODEL FOR DYNAMIC ADDITIONAL STRESSES IN LAYERED SUBGRADE UNDER TRAFFIC LOAD

作　　者：汤连生[1] 林沛元[1] 吴科[1] 徐通[1] 颜波[1] 

机构地区：[1]中山大学地球科学系,广东广州510275

出　　处：《岩石力学与工程学报》2009年第11期2208-2214,共7页Chinese Journal of Rock Mechanics and Engineering

基　　金：国家自然科学基金资助项目(40872205);广东省自然科学基金资助项目(07003738);广东省科技计划资助项目(2008B030303009)

摘　　要：针对路基路面系统成层性的特点,应用弹性层状体系理论对车辆循环动载下路基动附加应力的计算模型进行探讨。首先假设路基路面各层为弹性层状体,将弹性动力学控制方程中的应力和位移变换为模态坐标下的状态矢量,分离并消去动附加应力表达式中的时间变量;然后借助Laplace变换将偏微分动力学方程转化为含积分变量的线性方程组,再用矩阵方法求得层状路基在变换域中的传递矩阵,结合路面车辆动载边界条件,建立层状道路系统动附加应力量化模型;最后采用Matlab编程语言对模型进行数值计算。算例表明,所建议的模型在路面结构层中产生的误差较小,不超过12%,而在路基层中产生的误差较大,将近35%,但总体上,本模型能较好模拟交通荷载下,路基路面层中动附加应力的分布规律,具有实际工程应用的价值。In light of the stratification of the subgrade and pavement system, evaluation of calculation model for dynamic additional stresses under cyclic dynamic loads is concerned by the theory of elastic layered system. On the assumption that layers of the subgrade and pavement system are elastic, stresses and displacements in the control equations of elastic dynamics are transformed to state vector under modal coordinate, and time factor is separated and eliminated. Then linear equations set with variable of integration are derived from dynamics partial differential equations through Laplace transform, and the transfer matrix for layered subgrade system in the transform domain is achieved by using matrix method. Boundary conditions of dynamic loads imposed on pavement are considered to establish the dynamic additional stresses quantification model for layered road system. Numerical analysis is applied by using Matlab program. Results indicate that errors generated by the suggested model, compared with measured value, are less than 12% in the pavement layers and 35%in the subgrade layers. However, the suggested model reveals that the distribution characteristics of dynamic additional stresses reasonably in the subgrade-pavement system and is significant to practice.

关 键 词：土力学 交通荷载 层状路基 动附加应力 传递矩阵 

分 类 号：TU43[建筑科学—岩土工程]