低周反复荷载作用下十字形截面钢异形柱抗震性能试验研究

Experimental research on steel specially shaped columns with cruciform section under cyclic loading

通过对8个1∶2缩尺的十字形截面钢异形柱在低周反复荷载作用下的试验,研究了试件的受力变形形态、破坏模态,得到了试件的滞回曲线、骨架曲线、承载能力、延性性能、耗能能力等,分析了翼缘宽厚比、腹板高厚比和轴压比等参数对抗震性能的影响。考虑试件的初始缺陷、材料非线性和几何非线性进行了有限元分析。有限元计算和试验结果表明,在轴压比和翼缘宽厚比、腹板高厚比满足限值的条件下,十字形截面钢异形柱在罕遇地震作用下,其破坏模态为局部屈曲的塑性破坏,变形以塑性为主且发展充分,具有较高的承载能力,较好的延性和耗能能力,能够在强震区使用。本研究为工程应用和钢异形柱结构技术规程的编制提供参考。

The pseudo-static test on 8 one-half scale steel column models with cruciform section under cyclic loading is introduced in this paper. The deformation properties and the failure mode are discussed along with the hysteretic loops, skeleton curves, hearing capacity, ductility and energy-dissipation capacities. The effect of flange widththickness ratio, web depth-thickness ratio and axial compression ratio are reviewed. Finiteelement analysis is carried out based on initial geometric imperfection and geometric nonlinearity. The experimental results are close to the finite-element analysis results, which shows that the specially shaped steel column with cruciform section has excellent bearing capacity, good ductility and energy dissipation if certain flange width-thickness ratio, web depth-thickness ratio and axial compression ratio conditions are appropriate. The failure mode was local buckling instability failure with sufficient plastic deformation. The study evidenced that specially shaped steel columns with cruciform section can be used in seismic region. This study can provide background for practical engineering applications and design specification for steel structures with specially shaped columns.