傅山路云中河大桥力学性能分析

Mechanical Property Analysis for Fushan-Road Bridge over Yunzhong River

采用MIDAS/Civil有限元软件建立傅山路云中河大桥——5跨下承式复式钢箱系杆拱梁组合桥的空间有限元计算模型,分2种工况计算该桥在永久作用效应和永久作用效应+可变作用效应下的桥梁力学性能,计算结果表明:该下承式复式钢箱系杆拱梁组合桥的主梁最大压应力值为-14MPa,拱肋最大压应力值为-148MPa,均小于材料的设计抗压强度;吊杆安全系数最小值为3.1,满足桥梁规范关于吊杆最小安全系数不得小于2.5的规定,具有较大的安全储备;该桥梁在汽车荷载作用下位移满足桥梁设计规范关于正常使用极限状态下的变形要求;并采用Lanczos法对该桥进行动力特性分析。计算结果已为该拱桥的设计复核提供了参考。

Finite software MIDAS/Civil is used to establish a model of Fushan bridge over Yunzhong River ,which is one three-dimensional finite calculating model of Five-span through type bow-string arch bridge of compound-term steel box. Two working conditions are considered to calculate mechanical properties of the bridge on permanent load or permanent and variable load ~ Calculating results indicates that maximal compression stress in main beam is --14 MPa and maximal compression stress in arch rib is --148 MPa of the through type bow-string arch bridge of compound-term steel box. So, the two compression stress are all below design compression strength. Minimal safety factor of suspenders is 3.1, and it meets the bridge specify that minimal safety factor of suspenders should not below 2.5 and has a enough safety stock. Displacement of the bridge under vehicle load can meet limit deformation requirements in design specification for normal use, and Lanczos method is used to study Dynamic Characteristics of the bridge. Calculating results in this text have offered reference for design review of the arch bridge.