近爆作用下钢筋混凝土柱数值分析加载方法对比

Comparison of Numerical Analysis Loading Methods of RC Columns Under Near-field Explosion

为了研究近爆作用下不同数值分析加载方法对钢筋混凝土柱动力响应及破坏形式影响,运用AUTODYN对钢筋混凝土柱在近距离爆炸下的超压荷载进行模拟并提出一种荷载简化计算方法.基于LS-DYNA建立近爆作用下钢筋混凝土柱动态响应及其损伤破坏的三维有限元模型,近爆荷载分别采用简化后的荷载、Load blast命令和“炸药-空气-混凝土柱”流固耦合3种加载方法加载,将模拟结果与爆炸破坏试验结果对比,分析不同加载方法在误差、计算效率、所占内存等方面的特点.研究结果表明,简化荷载加载方式位移误差较小且所占内存较小,但需要掌握2种软件多次建模;blast-load计算模型加载方式建模简单、计算时间较短、所占内存较小、模型稳定但残余位移误差较大;“炸药-空气-混凝土柱”流固耦合加载方式建模较为复杂、计算时间较长、所占内存较大,但误差较小.

To study the influence of different loading methods for numerical analysis of reinforced concrete columns dynamic response and failure modes under near-field explosion,numerical simulations were conducted for the analysis on the overpressure of RC columns under near-field explosion by using AUTODYN,and a simplified method was proposed.Based on LS-DYNA,a 3D FE model was developed to analyze dynamic response and failure mechanism of the RC columns under near-field explosion.The near-field explosive loads were loaded by three loading methods including methods the simplified load,the load blast command,and the fluid-solid coupling of“explosives-air-concrete columns”.The simulation results were compared with the explosion destruction test results.The effects of different loading methods on error,computational efficiency,and memory occupied were investigated.Results indicate that the simplified load method has smaller displacement error and less memory,however,it is necessary to master two kinds of software modeling repeatedly.The load blast command loading model is simple,the calculation time is short,and the memory is small.The model is stable but the residual displacement error is large.The modeling of the fluid-structure coupled loading of the“explosive-air-concrete column” is complicated,the calculation time is long,and the memory is large,but the error is small.