李天华¹，  赵均海¹，  魏雪英¹，  董晓明²，  孔  巍³
   （1 长安大学建筑工程学院，西安 710061；2 长安大学公路学院，西安 710064；3 中国建筑股份有限公司，北京 100037）

[摘要] 在爆炸荷载下钢筋混凝土板的破坏可能引起人身安全甚至导致结构框架的连续倒塌。利用显式动力分析程序ANSYS/LS-DYNA( 13.0版本)建立钢筋混凝土单向板1/4数值模型，模拟其在爆炸荷载下的动力响应和破坏形态。混凝土采用脆性损伤模型，钢筋采用弹塑性模型，考虑了应变率效应和材料的失效。进行了不同折合距离下爆炸破坏模式分析以及结构动力响应参数分析，包括爆炸荷载强度、材料的强度、板的厚度、跨高比以及边界条件等对其爆炸荷载下挠度的影响。数值模拟的结果表明：在近距离小折合距离爆炸下，构件发生剪切破坏，远距离大折合距离爆炸下，构件发生弯曲破坏。混凝土的强度、板的厚度、跨高比、板边的约束情况均能明显影响板的动力响应和抗爆能力，钢筋强度影响甚小。
[关键词] 钢筋混凝土板；爆炸荷载；数值模拟；应变率效应
中图分类号：TU375.2    文献标识码：A  文章编号：1002-848X( 2012) Sl-0786-05

Dynamic response and parametric analysis on reinforced concrete slabs under blast loadings
Li Tianhua¹,  Zhao Junhai¹,  Wei Xueying¹,  Dong Xiaoming²,  Kong Wei³
(1 School of Civil Engineering,  Chang' an University,  Xi' an 710061,  China; 2 Highway School,  Chang' an University,  Xi' an 710064,  China; 3 China State Construction Eng.  Corp.  Ltd., Beijing 100037, China)

Abstract: The failure of reinforced concrete( RC) slabs under blast loadings may present a significant safety hazard to building occupants and even cause progressive collapse in frame structures in some cases. The numerical simulation of a 1/4 symmetry slab model using the finite element explicit code ANSYS/LS-DYNA version 13.0 was used to estimate the dynamic response and failure mode of RC one-way plates. Concrete was modeled using a brittle damage material model, and the reinforcement was modeled using a Von-Mises elasto-plastic material type with kinematic hardening.The erosion and the strain rate effects were included in the numerical model. A parametric investigation was conducted, including the effects of magnitude of the blast, material strength, thickness of slabs, span-depth ratio and boundary conditions on maximum deflections of RC slabs. The numerical simulation results showed that concrete strength, slab thickness, span-depth ratio and boundary conditions all have a sigruficant effect on deflection of RC slabs and their performance under blast loadings. The strength of steels has little effect on deflection of RC slabs and their performance under blast loadings.
Keywords: reinforced concrete (RC) slabs; blast loading; numerical simulation, strain rate effect