【摘要】 针对腹板宽厚比较大的H形截面钢框架梁塑性耗能区延性较差的问题,提出在其腹板设置纵向加劲肋以改善抗震性能的方法,并进行试验验证。通过4个梁腹板设置纵向加劲肋和1个未设置纵向加劲肋的梁柱刚接节点试件的反复加载试验,对框架梁端塑性耗能区腹板设置纵向加劲肋前后的抗震性能进行对比研究。试验以梁腹板采用弹性设计截面的试件为基准,考察在腹板设置一道、两道纵向加劲肋后塑性耗能区抗震性能的改善程度;并与塑性设计截面腹板梁的试件、部分塑化截面腹板设一道纵向加劲肋的试件进行抗震性能的比对。试验结果表明:设置纵向加劲肋可显著提高H形截面框架梁塑性耗能区的抗震性能;梁端塑性耗能区翼缘宽厚比满足塑性设计截面的要求,腹板采用弹性设计截面的宽厚比,当设置一道或两道纵向加劲肋时,可达到不低于塑性设计截面或GB 50011—2010《建筑抗震设计规范》二级抗震框架梁端耗能区的抗震性能要求;弹性设计截面腹板纵向加劲肋分隔的区格板件宽厚比与实腹梁腹板宽厚比相当时,抗震性能基本等价。更多还原

【Abstract】 To satisfy the seismic design requirement for the plastic energy dissipation region of H-section steel moment frame beam with relatively large width-to-thickness ratio of the web and consequently unacceptable ductility,a longitudinally stiffening method for the beam web was proposed to enhance the seismic performance of the beam,and experiments were performed for qualification. Seismic performance of the plastic energy dissipation regions of steel moment frame beams with and without web stiffening was compared and investigated by cyclic loading experiments on four rigid beam-column connection sub-assemblage specimens with longitudinally stiffened web and one specimen without stiffening. The experiment adopted a specimen with elastic design section for the beam web as a benchmark to investigate the performance upgrading of the plastic energy dissipation region with one and two longitudinal stiffeners for the beam web. Furthermore,seismic performance of the specimens was compared with the plastic design section specimen and the partial plastification section specimen with one longitudinal stiffener. The experiment result shows that longitudinally stiffening can considerably upgrade the seismic performance of the plastic energy dissipation region of H-section frame beam,the plastic energy dissipation region of beam with plastic design section for the flange and elastic design section for the web may achieve better seismic performance than that of the plastic design section or class2 frame beam required by GB 20011—2010 ‘Code for seismic design of buildings’ when using one or two longitudinal stiffeners,and an elastic design section beam with longitudinally stiffened web shows almost equivalent seismic performance to that of an unstiffened beam when its width-to-thickness ratio of the web sub-panel is equal to that of the latter.更多还原