钢筋砼桁梁桥侧倾稳定性分析的超级单元法

针对钢筋砼箱形截面桁梁桥的侧倾稳定性分析 ,提出一种基于薄壁杆件理论的新型超级单元 .通过采用结构矩阵分析中的逆步变换原理和静态凝聚方法 ,得到了超级单元刚度矩阵 ,并利用文中提供的算法编制了FORTRAN语言计算程序LSAP .由于超级单元具有较少的自由度 ,所以本文算法降低了对计算机内存和计算机时的需求 ,利用微机即可有效地分析工程问题 .文中对一桁梁桥设计方案进行了实际计算 ,并与桁梁桥挠曲扭转理论计算结果进行了对比

Lateral Stability Analysis of Truss Beam Bridgewith Box Section by Super Element Method

In this paper, a new type of super_element based on the thin_walled bars theory is presented for the lateral stability analysis of the reinforced concrete truss_beam bridge with a box_section. By the principle of contragradient transformation and the static condensation in structural matrix analysis, the super_element stiffness matrices are formed, and a microcomputer program LSAP in FORTRAN language is programmed by the presented method. Because of less degree of freedom in the super_element, the less computer interior memory and cost are needed, so the lateral stability of the bridge can be analyzed efficiently by the microcomputer. As a practical application, a designed truss_beam bridge is analyzed by the program LSAP, and the result comparison with an analytical method is given in the paper.