高强度钢材箱形柱滞回性能试验研究

Experimental study on hysteretic behavior of high strength steel box-section columns

为研究Q460高强度钢材箱形柱的抗震性能,对5个足尺试件进行了水平往复加载试验研究,分析了板件宽厚比、轴压比等因素对试件的承载力、破坏模式、耗能能力、变形能力和延性的影响。试验结果表明,Q460高强度钢材箱形柱具有很好的耗能能力和抗震性能,适用于抗震钢框架;除试件HB-1外其他试件本身及其柱脚节点均未发生焊缝开裂,证明设计合理、质量合格的Q460高强度钢材焊缝连接具有足够的承载力和良好的抗震性能;板件宽厚比越大,试件局部屈曲出现得越早,最大荷载对应的位移级越小,达到破坏时的位移级也越小;试件发生局部屈曲的范围及屈曲中心位置相对于试件截面高度的比值依次减小,所有试件最大屈曲位置距固定端0.25B～0.50B(B为等边箱型截面外边长),塑性区范围距离固定端0.72B～1.06B。根据试验结果,建议在轴压比不大于0.2时,Q460钢材箱形截面压弯构件板件宽厚比限值不应大于30;同时,钢框架柱在进行抗震设计时,其板件宽厚比限值应与轴压比相联系,轴压比越大,板件宽厚比限值应越小。

In order to study the seismic behavior of Q460 high strength steel box-section columns, 5 full-scale specimens were tested under cyclic loading. The influences of the width-to-thickness ratio and axial-load ratio on the load carring capacity, failure modes, energy dissipation capacity, deformation capacity and ductility were analyzed. The test results indicate that Q460 high strength steel box-section columns have excellent energy dissipation capacity and seismic behavior and are applicable for seismic steel frames. No welds of the specimens or the column bases exceptspecimen HB-1 crack, which proves that Q460 high strength steel welds by reasonable design and qualified quality have enough load carrying capacity and seismic behavior. With higher plate width-to-thickness ratio, local buckling occurs earlier, the displacements corresponding to the maximum load carrying capacity and ultimate failure are both smaller, and the ratios of the range and the center of the local buckling to the specimen section height decrease. The distance between the maximum local buckling position and the fixed end for all the specimens is 0. 25B - 0.50B. The plastic range is 0. 72 B - 1.06 B. Based on the test results, it is suggested that, the plate slenderness limiting value for Q460 high strength box-section columns is 30 when the axial-load ratio is not greater than 0. 2. The width-to- thickness ratio limiting values for steel columns should be related to the axial-load ratio.