爆炸冲击作用下预制节段拼装桥墩的动态响应与损伤分析

为研究爆炸冲击作用下预制节段拼装桥墩的动态响应与损伤,采用ANSYS/LS-DYNA建立圆形截面预制节段拼装桥墩受爆的三维实体分离式模型。通过与已有实验结果的对比分析,验证了该模拟方法的可靠性。基于该模型,研究了爆炸冲击作用下节段长细比、初始预应力水平及桥墩体系对圆形截面预制拼装桥墩动态响应与损伤的影响规律。结果表明:减小节段长细比使墩身由剪切破坏逐渐变为节段间相对位移,并减小墩身的整体侧向位移;提高初始预应力水平可以在一定程度上提高桥墩的抗爆性能;爆炸冲击作用下混合体系桥墩兼具完全节段和整体现浇桥墩的破坏特征。

Dynamic response and damage analysis of precast segmental piers under blast impact

In order to study the dynamic response and damage of the precast segmental pier under the impact of explosion, the three-dimensional separate models of the circular-section precast segmental bridge piers under explosion are established based on ANSYS/LS-DYNA. The reliability of the simulation method is verified by comparing with the previous experimental results. The influence of slender ratio of segments, initial post-tensioning level and pier system type on the dynamic response and damage of the circular-section precast segmental pier under blast are investigated based on the verified model. The results show that the decrease of segment slender ratio makes the precast piers gradually change from shear damage to inter-segment displacement and it can reduce the lateral displacement of the pier; the increase of the initial post-tensioning can improve the anti-blast performance of the piers to some extent; the piers with the hybrid system under blast have both the failure characteristics of the segmental and monolithic piers.