摘要
采用试验和数值的方法对梁腹板开圆孔的钢框架抗震性能进行了研究。试验结果表明:在设计水准下腹板开圆孔的钢框架仍能够满足现有规范的相关要求,结构性能并没有因为梁腹板开孔削弱而降低;在强震作用下,梁腹板削弱处率先形成空腹梁机制,结构通过梁的局部变形来耗散地震能量,形成所谓的"强柱弱梁,强节点弱构件"延性框架。该文以一栋在Northridge地震中梁柱节点遭受严重破坏的17层钢框架结构为算例,对腹板开圆孔的钢框架抗震性能进行了数值分析。分析结果表明:在原框架的梁腹板开设一定大小的圆孔后,并没有降低结构的刚度;在强震作用下,腹板开圆孔的钢框架形成了"强柱弱梁、强节点弱构件"的延性框架,最大塑性区移至梁腹板削弱处,最大限度的减小了梁柱连接处的转角,能有效的避免梁柱连接焊缝的脆性断裂,提高了钢框架结构的抗震性能。
Experimental study and numerical analysis on the aseismic behaviors of steel MRF including opening in beam web are carried out. Experimental results show that steel MRF including opening in beam web closed to connection can satisfy the design requirement. In the action of serve earthquake, Vierendeel-girder mechanism is formed in the weakened area, and the seismic energy is dissipated by local deformation of beam. The failure mode of steel MRF including opening in beam web is in conformity with the requirements of a ductile frame, i.e., ＂strong column-weak beam, strong connection-weak component＂. A 17-story steel MRF building damaged during the Northridge earthquake is taken as an example to investigate the aseismic behaviors of steel MRF including opening in beam web. Analysis results show that with appearance of opening in beam web, the rigid of steel MRF is not weakened, and the failure mode of a ductile frame is formed. The maximum plastic zone moves to the weakened areas. Rotations around beam-to-column connection decrease and brittle weld fracture can be avoided. Aseismic behaviors of steel MRF is improved due to opening in beam web.
出处
《工程力学》
EI
CSCD
北大核心
2009年第1期64-73,共10页
Engineering Mechanics
基金
国家自然科学基金项目(50278001)
北京交通大学科技基金项目(2007XM029)
关键词
梁腹板开圆孔
钢框架
抗震性能
试验研究
数值分析
延性
opening in beam web
steel moment resisting frame
aseismic behaviors
experimental study
numerical analysis
ductility
