承插式预制桥墩在车辆碰撞下的动力响应模型试验研究

Model experimental analysis on the dynamic response of a socket prefabricated pier under vehicle collision

为获得承插式装配桥墩的抗车撞性能,针对一种预制墩柱与预制基础连接界面不做粗糙处理的承插式连接构造,进行了4个不同嵌入深度的承插式桥墩试件与1个整体式现浇桥墩试件在车辆碰撞作用下的模型试验,分析了承插式连接形式及嵌入深度对桥墩受车撞响应的影响。结果表明:车速和承插深度是影响该类桥墩车撞动力响应的重要因素,桥墩的加速度有随车速提高而增大的趋势,其损伤程度随墩柱嵌入深度的增加逐渐减小;1.0倍墩柱直径嵌入深度的承插式桥墩的最终破坏形态与整体式的基本相同,且在钢筋应变极值增减趋势及幅值方面与整体式桥墩基本相同。建议工程应用中在连接界面不做粗糙处理的情况下,承插式连接的最小嵌入深度取为1.0倍墩柱直径。

In order to obtain the anti-collision performance of a socket assembled bridge pier,a socket connection structure without rough treatment on the connection interface between the precast pier column and the precast foundation was proposed.Through the model test of four socket bridge pier specimens with different embedment depths and one cast-in-place specimen under vehicle collision,the influences of the socket connection form and embedment depth on the dynamic response of bridge piers under vehicle collision were studied.The results show that the vehicle speed and embedment depth are important factors that affect the dynamic response of the socket bridge pier subjected to vehicle collision.The acceleration of bridge piers tends to increase with the increase of vehicle speed,and the damage degree of bridge piers gradually decreases with the increase of pier column embedment depth.The final failure form of the socket pier with an embedment depth of 1.0 times the pier column diameter is basically the same as that of the cast-in-place one,and the socket pile is basically the same as the cast-in-place pier in terms of the distribution and magnitude of maximum reinforcement strain.It is thus suggested that the minimum embedment depth for socket connection can be 1.0 times the pier column diameter without rough treatment on the interface between the precast pier column and the precast foundation in bridge engineering application.