汽车冲击荷载作用下桥墩动力响应分析

Dynamic Response Analysis of Bridge Pier under Vehicle Collision

为了研究钢筋混凝土桥墩的抗冲击性能,在已有试验的基础上,建立了与试验结果吻合良好的数值模型,验证了钢筋混凝土模型的合理性,并且建立了三维多跨钢筋混凝土桥梁与汽车的撞击模型。通过对不同混凝土强度的桥墩进行撞击分析,研究了冲击力时程曲线、桥墩变形、弯矩响应、剪力响应、轴力响应和桥墩振动周期与阻尼比。结果表明:提高混凝土强度不能显著提高桥墩的抗冲击能力,但可以降低桥墩的损伤;提高混凝土强度能够降低桥墩的峰值位移;提高混凝土强度能够降低桥墩的震动周期。

In order to study the impact resistance of reinforced concrete piers,on the basis of existing tests,a numerical model was established.The results of numerical model were in good agreement with that of the experimental,and the rationality of the reinforced concrete model was verified.The impact model of three-dimensional multispan reinforced concrete bridges and vehicle was established.The impact analysis of piers with different concrete strength was carried out.The impact time history curve,pier deformation,moment response,shear response,axial response,pier vibration period and damping ratio were studied.The results show that improving the concrete strength can not significantly improve the impact resistance of the pier,but can reduce the damage of the pier;increasing the concrete strength can reduce the peak displacement of the pier;improving the concrete strength can reduce the vibration period of the pier.