地震作用下H型钢框架柱局部稳定性能

Local Stability of H-shaped Steel Columns Under Earthquake

为研究热轧H型钢柱在不同轴压比和截面宽厚比下的抗震局部稳定性能,设计制作了5个热轧H型钢柱试件,采用试验和有限元分析软件对试件进行低周往复加载,分析各试件的滞回性能、强度退化、轴向缩短、截面变形程度、塑性铰长度等性能。结果表明:轴压比和截面宽厚比对试件的局部稳定性能影响较大,增大轴压比或翼缘宽厚比和腹板高厚比,试件的滞回曲线退化更明显、更早出现局部屈曲,强度退化速率更快,轴向缩短量、塑性铰截面变形程度以及塑性铰长度增大;轴压比对截面塑性发展的影响较小,翼缘宽厚比和腹板高厚比较小的试件,截面塑性发展更加充分。

To study the local seismic stability of hot-rolled H-shaped steel columns under different axial pressure ratios and section width-thickness ratios,a series of dynamic cyclic tests and finite element analysis were conducted on five designed specimens,the hysteretic behavior,strength degradation,axial shortening,section deformation,plastic hinge lengths and other mechanical performances of each specimen were investigated.The results showed that the local seismic stability of specimens were influenced with these two factors.Specimens with higher ratios showed more obvious degradation of hysteretic curve,earlier local buckling,faster strength degradation,larger axial shortening,greater deformation degree of plastic hinge section and longer plastic hinge length.Besides,with the diminution of flange width-thickness ratio and web height-thickness ratio,the plastic behavior was fully developed,and the axial pressure ratio has less influence on plastic strength development.