单层单跨变截面轻型门式刚架结构振动台试验研究  

Shaking table test on single-story single-bay light-weight portal frames with tapered members

作　　者：苏明周[1] 王振山[1] 王乾 申林 

机构地区：[1]西安建筑科技大学结构工程与抗震教育部重点实验室,陕西西安710055 [2]北京国冶锐诚工程技术有限公司,北京100096 [3]中国建筑标准设计研究院,北京100048

出　　处：《土木工程学报》2012年第10期98-108,共11页China Civil Engineering Journal

基　　金：科技部科研院所专项基金(NCSTE-2007-JKZX-258);国家自然科学基金(51178382)

摘　　要：为研究轻型变截面门式刚架的抗震性能,进行了两个由四榀刚架组成的1/3缩尺模型试件的振动台试验,得到在不同地震工况下试件的动力反应,包括动力特性、加速度反应、位移以及应变反应等,并得到试件的破坏形式。试验分析结果表明:试件破坏形式为柱脚螺栓松动和刚架梁局部屈曲破坏;罕遇地震作用下,结构刚度退化明显、变形较大,塑性发展潜力不大;试件的阻尼比约为0.03。基于变形破坏准则的抗震分析表明:小震作用下,试件基本完好;中等地震作用下,试件发生轻微破坏;罕遇地震作用下,试件发生中度破坏,但远未到倒塌程度。抗震承载力验算表明:底部剪力法算得的地震力大于实际地震反应,表明底部剪力法可以安全地用于门式刚架结构地震力的计算。综上,门式刚架结构具有良好的抗震性能,完全能够满足"三水准"抗震设防准则。Shaking table tests on two 1/3 scaled models of steel portal frame structure have been carried out to study their seismic behaviors,with each model consisting of four single-story single-bay frames with tapered beams and columns.Based on the test results,the dynamic responses of two specimens are obtained under different seismic intensities,including structural dynamic characteristics,the acceleration response,displacement and strain variation,together with the failure mode of specimens.Test results reveal that the failure modes include bolts loosening of the column feet and local buckling of the taper beams.In rare seismic actions,the structural stiffness degenerates greatly,the deformation is obvious,but the ability of plastic deformation is insignificant,with the damping ratio being about 0.03.According to the deformation failure criterion of seismic analysis,the specimens are almost intact under frequent seismic actions,and slightly damaged under moderate seismic actions,while moderately damaged without risk of collapse under rare seismic actions.Comparison of total seismic base shear force evaluated using base shear method with that from test indicates that base shear method can be employed to calculate the seismic forces of portal frames.The portal frame structures perform well in seismic actions and can fully satisfy the ＂three level＂ seismic fortification requirements.

关 键 词：门式刚架 振动台试验 破坏形式 动力特性 抗震性能 

分 类 号：TU392.5[建筑科学—结构工程]