受冲击格构式钢拱弹塑性失稳数值模拟与试验研究毕业论文

学位论文受冲击格构式钢拱弹塑性失稳数值模拟与试验讨论Study on Elastic-plastic Bucking of Steel Lattice ArchAffected by Impact: Simulationand Experiment本文首先使用 ABAQUS/Explicit 模拟了刚体横向冲击弹塑性格构式钢拱的过程，讨论了各种因素对冲击响应的影响,得出：随着冲击速度的增加，刚体块嵌入格构拱拱顶钢管深度逐渐增大，冲击荷载最大峰值和冲击接触时间亦显著增大；随着质量比的增加，刚体块嵌入深度和冲击荷载最大峰值逐渐减小，接触时间增大；随着矢跨比的增大，冲击荷载最大峰值和接触时间逐渐减小，刚体块嵌入深度增大；随着格构拱跨度的增大，冲击荷载最大峰值、接触时间和刚体块嵌入深度都逐渐增大；随着格构拱壁厚的增大，冲击荷载最大峰值逐渐增大，刚体块嵌入深度和接触时间逐渐减小。本文通过分析刚体冲击弹塑性格构式钢拱过程，提出了基于整体变形和能推断弹塑性格构拱动力屈曲的判别准则。根据判别准则得出：随着冲击速度和刚体质量的增大，屈曲时间减小；随着刚体块的质量增大，临界冲击速度减小，当刚体块质量较大时，临界屈曲速度变化较小。采纳应变电测技术对格构式钢拱在冲击作用下的动力响应进行试验讨论，发现格构式钢 拱在落锤的冲击作用下结构破坏形式有两种情况，分别为：（1）支座处破坏；（2）弹塑性大变形破坏。在两种破坏形式下结构均发生整体失稳，且为平面外失稳。关键词：格构式钢拱，冲击荷载，接触时间，动力屈曲，试验讨论AbstractThis paper firstly used ABAQUS/Explicit to simulate the process of elastic-plastic steel lattice arch transversely impacted byrigid body ,and the impact response effected by various factors was studied.The main conclusions are as follows: when the velocity of rigid body is increasing, the depth embedded by rigid body in steel tube of the lattice arch vault changes larger, the impact load peak value changes greater, the contact time presents an significant increase; with the increase of mass ratio, namely the quality of the rigid block is smaller, the depth embedded by rigid body in steel tube of the lattice arch vault and the impact load peak valuechange smaller, the cont...