爆炸荷载作用下钢柱的动力响应与影响因素分析

Dynamic Response and Influence Factor Analysis of Steel Columns under Blast Loading

采用有限元软件ANSYS/LS-DYNA,建立钢柱有限元模型,模拟爆炸荷载作用下钢柱的动力响应,并对影响钢柱动力响应的主要因素进行数值分析。考虑了不同爆炸荷载、材料失效应变、单元网格密度、柱高、柱截面尺寸和柱承担的轴向压力等参数的影响。通过对钢柱动力响应时程曲线进行分析,研究爆炸荷载作用下钢柱响应特性及其破坏机理;通过分析,得到各参数对其动力响应的影响规律。分析结果表明:增大柱的截面尺寸,能够降低柱跨中水平位移;增大柱截面高度,能有效地提高钢框架柱的抗爆承载力;在钢柱抗爆设计中,应控制其所承受的轴向压力大小,轴压比值不宜超过0.3。

The finite element models of steel column were built by using finite element software ANSYS/LS-DYNA, and the dynamic responses of the steel column and its main influence factors were numerically analyzed. The influences of the different blast load, material failure strain, ele- ment mesh density, height and section size of steel column, and axial pressure of the steel columne were considered. The dynamic response time history curves of steel column were ana- lyzed and response characteristics and damage mechanism of steel colum under blast loading were studied. Through analysis the law of each parameterrs influence on the response of the column was obtained. The results show that the horizontal displacement of the mid-span at the steel col- umn can be reduce with the increase of the section size of column, and the blast resistance capaci- ty of steel column can be effectively improved especially with increase of height of column sec- tion. In the design of anti-explosion of steel column, axial pressure of steel column should be controlled as the axial compression ratio should not be more than 0.3.