曲线箱梁桥的空间传递矩阵

The spatial transfer matrix of curved box-girder bridge

为了分析曲线箱梁桥的受力情况,将传递矩阵法用于曲线箱梁桥的受力分析,以变化固定端的悬臂梁作为单元基本计算体系,利用平衡方程、卡式定理及虚功原理推导了弹性曲线箱梁的显式空间传递矩阵,并考虑了截面剪切中心与形心不重合的影响。为验证公式的正确性,分别采用传递矩阵法与有限元法对某一单跨曲线箱梁桥进行空间受力分析,结果显示2种方法计算结果基本吻合,而传递矩阵法划分较少单元却可达到很高的精度,计算效率大大提高。表明该公式正确,推导方法可行,可推广应用于其他结构在不同荷载情况下传递矩阵的推导。

To study the stress state of the curved box-girder bridge,the transfer matrix method was used to analyze the curved box-girder bridge. Based on the basic computing system of a cantilever beam with the fixed end changed by the calculation model,the explicit spatial transfer matrix of an elastic curved box-girder was deduced by balance equations,Castigliano＇s theorem and the principle of virtual work. The shear center not coinciding with the centroid of the cross section was also considered in the matrixes. To verify the validity of the formulas,a single span curved box-girder bridge under spatial loads was calculated by the finite element method（ FEM） and the transfer matrix method. It showed that the results calculated by the two methods are basically consistent,while the transfer matrix method has fewer units but a higher accuracy,so it can greatly improve the computational efficiency. The formula is valid and the derivation method is feasible. It appears that it can be applied to deriving the transfer matrix of other structures under different load cases.