齿板滑移对轻型木桁架挠度的影响

Effects of metal plates' slippage on deflection of light wood trusses

以齿板连接轻型木桁架为研究对象,研究了齿板滑移对木桁架各结点位移的影响。采用有限元分析方法,运用弹簧的串联原理将两个虚拟变刚度单元及一根实体杆单元整合为等效刚度杆件单元,建立单元刚度矩阵和整体刚度矩阵,再运用普通桁架的计算理论来计算引入变刚度单元模拟齿板连接的受力情况及位移情况。根据以上原理用Fortran90编制了齿板连接木桁架MPT Design设计程序,并根据木结构试验规范要求通过木屋架试验验证该程序的正确性。

The performance of light wood trusses connected by metal plates was investigated in this paper. A methodology and program was developed to compute the displacements of each joint of light wood trusses caused by slippage of metal plates. Based on the principles of the finite element method, the spring＇ s series connections was employed to combine two virtual viable stiffness bars and one entity bar into an equivalent equal stiffness bar, thus the unit stiffness matrix and integrated stiffness matrix were established. Computation theory of normal truss structure was then adopted to compute the forces and displacements of the virtual equal stiffness bars after variable stiffness light wood truss connected by metal plates was introduced. MPT Design, which was based on the above theory and Fortran90, was developed to execute the computation. This methodology was proved to be viable by comparing the computed result with the experimental specifications of wooden structure.