爆炸荷载作用下型钢混凝土柱的失效时间研究

Study on failure time of steel reinforced concrete column under explosion load

为了研究爆炸荷载作用下型钢混凝土柱的失效时间,以某建筑工程项目中采用的型钢混凝土柱为背景,利用软件LS-DYNA建立复杂炸药-空气-型钢混凝土柱三维有限元模型。然后通过数值仿真结果与试验数据对比验证有限元模型及其分析方法的合理性和正确性。最后研究了不同轴压比不同爆炸比距离下型钢混凝土柱的失效过程、失效模式和失效时间。通过对典型算例的分析表明,在临近爆炸场内,型钢混凝土柱绝大部分发生严重损伤和彻底失效;只有当爆炸比距离较大和轴压比较低时,才会发生中等损伤;未出现轻微损伤。轴压比对型钢混凝土柱的失效模式和抗爆性能有很大影响,在轴压比从0.40到0.60范围内有利于提高型钢混凝土柱的抗爆性能。型钢混凝土柱的失效时间从18~118 ms,该型钢混凝土柱失效时间的计算公式可以很好地预测型钢混凝土柱的失效时间。

To investigate the failure time of the steel reinforced concrete column under explosion load,the steel reinforced concrete column used in a structural engineering project is taken as the background.First,a complicated 3D numerical simulation model of TNT-air-column is developed using the software LS-DYNA.Thereafter,the rationality and correctness of the finite element model and its and its analysis method are validated by comparing the numerical simulation results with the experimental data.And finally,the failure process,failure mode and failure time of the steel reinforced concrete columns with different axial compression ratios and different explosion scaled distances are studied.Based on typical case analyses,the research findings indicate that the high damage and complete failure occur mostly on the steel reinforced concrete column in an adjacent physical field of explosion;the medium damage occurs only when the explosion scaled distance is higher and the axial compression ratio is lower;and the low damage does not occur at all.The axial compression ratio has a great influence on the failure mode and the explosion resistance of the steel reinforced concrete column,and the axial compression ratio within the range from 0.40 to 0.60 is conducive to improve the explosion resistance of the steel reinforced concrete column.The failure time of the steel reinforced concrete column can range from 18 to 118 ms.The calculation formula used in the proposed method can provide a good prediction of the failure time of the reinforced concrete column.