参数变化对PRC弯梁桥动力性能影响仿真分析

Effect of Parameters on Dynamic Performance of PRC Curved Box-section Girder Bridge

为分析参数变化对PRC弯梁桥动力性能的影响,推导了考虑预应力效应的弯梁桥单元刚度矩阵,并建立了考虑预应力效应的PRC连续箱形弯梁桥模型。采用数值仿真方法,研究了预应力、曲率半径、弯扭刚度比、约束情况、截面翘曲及车速等对PRC箱形弯梁桥自振特性的影响,研究了预应力和曲率半径对PRC箱形弯梁桥动力响应的影响。结果表明:各种参数的变化对PRC弯梁桥的动力性能均有影响,且具有一定的规律性,给出了各设计参数的合理取值范围,对PRC弯梁桥的设计具有一定的参考价值。

The purpose of this paper is to analyze the effect of the design parameters on the dynamic performance for PRC curved box girder bridge. Element stiffness matrix is deduced, taking pre-stressing effects into consideration. The PRC continuous curved box girder bridge model is established, including the influence of prestressing effects. In the numerical simulation, the effect of design parameters, such as pre-stress, curvature radius, bending-twisting stiffness ratio, constraint formalism, and cross-sectional warp, etc, on the free vibration characteristics are analyzed. The effects of the pre-stress and curvature radius on the dynamic responses are also analyzed in the simulation. The results reveal that dynamic performance of PRC curved girder bridge is affected by the changes of various parameters and some rules may be found. The rational value domains of designing parameters are obtained. The conclusions can be used in the optimizing design of PRC curved box-section girder bridge.