【摘要】 地基和基础的柔性对上部结构的变形或总体线刚度有一定影响,在车桥耦合振动等结构静、动力分析中合理模拟基础刚度是必要的。针对当前常用基础刚度模拟方法的局限性,提出一种基础刚度有限元模拟的正交三梁模型,其原理是采用具有1个公共节点的3个正交的梁单元,通过联合求解确定3个梁单元各自的刚度特性,从而使3个正交单元公共节点处的刚度和承台中心的基础刚度等效。通过实例验证,该正交三梁模型可准确模拟基础刚度矩阵的各主元素和交叉项,简单实用,便于结构有限元建模,具有推广价值。更多还原

【Abstract】 The flexibility of ground base and foundation has certain influence on the deformation or global linear stiffness of superstructure.It is hence necessary to reasonably simulate foundation stiffness in the static and dynamic analysis of the structure especially under the vehicle and bridge coupling vibration.In view of the limitations of several current commonly-used simulation methods for the foundation stiffness,a three-orthogonal-beam model for the finite element simulation of the foundation stiffness is proposed.The principle of the model is to determine the respective stiffness characteristic of each of the three beam elements and to make the stiffness at the common node of the three beam elements to be equivalent to that of the foundation under the center of pier base by using the three beam elements having a common node and through the union solution.The verification of practical examples demonstrates that the model can correctly simulate various principal and cross terms in the foundation stiffness matrices,is simple and practical,easy to create finite element models for the structure and is of value of wide application.更多还原