爆炸与火荷载联合作用下钢柱变形与破坏的数值分析

为了探讨爆炸和火荷载对钢柱的联合作用效果，以有限元软件ABAQUS为基础，建立了爆炸和火荷载对钢柱联合作用的三维有限元数值分析方法，包括显式准静态分析、显式动力学分析、显式热传导及热应力耦合分析3个步骤，计算过程中考虑了应变速率和高温软化效应对材料本构关系的影响。通过典型的钢柱抗火试验数据验证了分析模型和方法的可行性，并利用该方法定量分析了先爆炸后火荷载联合作用下钢柱的变形与破坏特点。结果表明，爆炸荷载降低了钢柱的耐火极限。

Numerical simulation of deformation and failure of steel columns subjected to blast and fire

To investigate the effects of steel columns subjected to combined actions of explosion and fire, a three dimensional numerical approach was developed based on the finite element software ABAQUS. The numerical approach consisted of three analytical steps including explicit quasi static analysis, explicit dynamic analysis and explicit fully coupled thermal stress analysis. Rate sensitivity and softening effect of temperature on the mechanical properties of steel were considered simultaneously. The analytical model and approach were validated by a typical fire resistance test of steel columns, and the responses of the steel columns subjected to the combined actions of explosion and fire were analyzed by the proposed approach quantificationally. The analytical result shows that the fire resistance of the steel columns is reduced by blast loads.