K8型单层球面网壳基于AUTODYN的外爆响应分析

RESPONSES OF SINGLE-LAYER RETICULATED DOMES SUBJECTED TO EXTERNAL BLAST LOADING USING AUTODYN

该文采用显式动力有限元软件AUTODYN对K8型单层球面网壳在外爆荷载下的动态响应进行了研究。数值模拟中采用流固耦合方法施加荷载,钢材采用多段线性模型,首先验证了AUTODYN进行近场爆炸分析和远场爆炸分析的准确性;考察了跨度为20 m的网壳结构在外爆荷载下的荷载传播规律、最大节点位移变化规律以及塑性杆件发展规律,考察了跨度为40 m网壳结构在TNT质量、炸点距离以及炸点高度参数变化下的结构响应规律。数值分析的结果表明:AUTODYN具备准确进行近场爆炸和远场爆炸分析的能力;单层球面网壳在外爆荷载下主要经历两次冲击波荷载,最大节点位移出现在第一次冲击荷载作用时,结构杆件的塑性发展在0.05 s后基本结束;网壳结构的响应随TNT质量增加和炸点高度增加而加大,随炸点距离增大而减小。

The dynamic responses of single-layer reticulated domes are analyzed through the explicit dynamic finite element software AUTODYN. The load is applied using the FSI method, and the material is adopted using a multi-segment linear model for steel. First, the accuracy is verified by analyzing near-field and far-field explosions. Then the responses of a 20 m span reticulated dome are obtained under external blast loading, including the loading spread, change in maximum nodal displacement, and development of plastic members. The laws governing structural response are researched, accounting for the mass of TNT, explosion distance, and explosion height. The results of numerical simulations indicate that AUTODYN can be used to analyze near-field and far-field explosions; the reticulated dome experiences two main shock wave loadings under external blast loading and the maximum nodal displacement occurs at the first shock wave loading; the plasticity development of structural members ends at 0.05 seconds; the structural responses strengthen with the increase of TNT mass and the explosion height, but weaken with the increase of explosion distance.