汽车制动力对不同结构体系斜拉桥的受力响应研究

Study on Stress Response of Automobile Braking Force to Cable-stayed Bridges with Different Structural Systems

摘要:

为探究汽车制动力对斜拉桥受力性能的影响，基于有限元，建立参数相同的3种不同结构体系斜拉桥主桥模型，分析了3种不同结构体系斜拉桥的受力性能受汽车制动力的影响情况。结果表明：刚构体系斜拉桥的受力性能受汽车制动力的影响最小，相较于漂浮体系和半漂浮体系斜拉桥，其主梁梁端纵向位移分别减小了96.49%和96.46%；3种结构体系斜拉桥的主梁内力响应受汽车制动力的影响均较小；刚构体系斜拉桥的主塔塔底弯矩受汽车制动力的影响较小，相较于漂浮体系和半漂浮体系斜拉桥，其主塔塔底弯矩分别减小了79.5%和79.6%；制动力对3种结构体系斜拉桥主塔的轴力和剪力影响很小。通过综合对比以及对实际建设情况的分析，选择了刚构体系作为斜拉桥的最终结构体系。

Abstract:

To explore the impact of vehicle braking forces on the mechanical performance of cable-stayed bridges, based on finite element, three main bridge models of cable-stayed bridges with the same parameters but different structural systems are established to analyze the influence of the braking force of automobiles on the mechanical performance of cable-stayed bridges with three different structural systems. The results show that the mechanical performance of the rigid-frame system cable-stayed bridge is least affected by the braking force of the vehicle. Compared with the floating system and semi-floating system cable-stayed bridges, the longitudinal displacements at the ends of its girder have decreased by 96.49% and 96.46% respectively. The internal force responses of the girders of the three structural systems of cable-stayed bridges are all less affected by the braking force of automobiles. The bending moment at the bottom of the main pylon of a rigid-frame cable-stayed bridge is less affected by the braking force of the vehicle. Compared with the floating system and semi-floating system cable-stayed bridges, the bending moments at the bottom of its main pylon have been reduced by 79.5% and 79.6% respectively. The braking force has little influence on the axial force and shear force of the pylons of the three structural systems of cable-stayed bridges. Through the comprehensive comparison and analysis of the actual construction situation, the rigid-frame system is selected as the final structural system of the cable-stayed bridge.