大跨拱与刚构组合桥梁的系杆调整作用

为了解决大跨系杆拱与刚构组合桥梁采用分段系杆调节内力与线形时，其刚构系杆与中跨系杆的作用相互影响的问题，针对1座该类型桥梁的设计方案，采用SAP2000软件建立了三维有限元模型；考虑施工过程的影响，通过分析确定合理的张拉力，使几个关键部位的应力与变形同时满足要求．结果表明，中跨系杆张拉力主要由刚构承担．最后指出，计算恒载内力时，可以不考虑几何非线性的影响．

Adjustment Function of Tie Bars of Long-Span Arch and Rigid Frame Combination Bridge

A three-dimensional FE (finite element) model was established for a long-span arch and rigid frame combination bridge using software SAP2000 in order to solve the problem of interaction induced by tensioning the tie bars of rigid frame and main span and adjust its internal forces and geometry. To meet the requirements for stresses and deformations in the key locations of the combination bridge, reasonable tensioning forces were determined on the basis of construction processes. The result shows that the tensioning force of main span is mainly undertaken by rigid frame. Finally, it was pointed out that the influence of geometrical nonlinearity on internal forces may be ignored under the condition of dead load.