采用界面单元协调子结构方法研究

A METHOD TO COORDINATE SUBSTRUCTURES BY USE OF INTERFACE ELEMENTS

子结构混合试验在研究复杂工程时,需要针对不同物理的物理性质划分子结构,比如土和结构,这些子结构的单元类型和网格划分通常不同,为了使混合试验更灵活地划分子结构,该文提出利用界面单元方法,基于广义变分原理,将两子域凝聚在边界上的刚度矩阵与界面单元刚度矩阵组装成耦合结构的整体刚度矩阵,进而求解新的平衡方程即可得到各个耦合子域的位移。同时,将传递函数的概念引入界面单元方法中,通过二维自由度和三维自由度之间的传递函数,解决了具有不同自由度单元的子结构之间的耦合问题。最后,利用板梁受竖向地震动作用的案例验证了界面单元和传递函数结合的方法的可行性和精确性。

In order to coordinate substructures with distinct physics in a hybrid test framework, this paper utilizes the interface element method to build up the overall stiffness matrix based on the general variational principle, where the statically condensed boundary stiffness matrices of substructures and the stiffness of interface elements are combined. This strategy makes the hybrid test more flexible particularly facing the substructures with different element types and meshes. Meanwhile, a transfer function was introduced to the method to correlate the subdomains with different numbers of degrees of freedom. Finally, the nonlinear time history analysis was conducted on the shell-beam model, which fully demonstrates the feasibility and the accuracy of the interface element method.