强约束大尺寸钢筋混凝土柱轴心受压试验研究  

Experimental study on axial compressive behavior of full-scale reinforced concrete columns with close confinement

作　　者：张微敬[1] 张兵[1] 蒋孝鹏[1] 李振宝[1] 

机构地区：[1]北京工业大学建筑工程学院,北京100124

出　　处：《地震工程与工程振动》2013年第1期106-114,共9页Earthquake Engineering and Engineering Dynamics

基　　金："十一五"国家科技支撑计划课题项目(2009BAJ28B01)

摘　　要：为研究箍筋强约束钢筋混凝土柱的轴心受压性能,完成了7根配箍特征值0.22-0.47、截面尺寸600mm×600mm的大尺寸钢筋混凝土柱试件的轴心受压试验研究。结果表明,试件的破坏形态均是纵筋受压屈曲,中部箍筋外凸,部分箍筋拉断,混凝土保护层剥落;除个别试件外,大部分试件核心区混凝土未压碎;强约束能有效提高钢筋混凝土柱的轴心受压承载力和竖向变形能力;达到峰值竖向应力时,纵向钢筋受压屈服,提供竖向承载力,箍筋受拉屈服,对核心混凝土起到约束作用。以小尺寸试件试验建立的约束混凝土应力-应变关系,可以较好地预测本文试件峰值前的应力-应变关系和峰值应力,但有可能高估混凝土的峰值应变及峰值后的变形能力。To investigate the axial compressive behavior of reinforced concrete columns with close confinement, a total of seven full-scale reinforced concrete columns with stirrup characteristic values in the range 0.22 - 0.47 andsection dimension 600 mm× 600 mm were tested under concentric compression loading. The test results indicated that all specimens failed in a similar way. The longitudinal bars were buckled in compression; the peripheral stirrups were bowed out and several stirrups were fractured. The cover concrete in the mid-height section of specimens were spalled seriously. However, the core concrete of specimens was not crushed. The axial compressive bearingcapacity and deformation ability of reinforced concrete columns could be improved by close confinement. When specimens reached the ultimate bearing capacity, the longitudinal reinforcement was yielded and provided axialbearing capacity for specimens. The transverse reinforcement reached tensile yield strength and provided effective confinement for the core concrete. The stress-strain relationship before peak stress and the peak stress were wellpredicted by existing stress-strain model based on small size specimens, but the peak strain and the deformation ability after peak stress may be overvalued.

关 键 词：箍筋强约束 大尺寸 钢筋混凝土柱 轴心受压试验 

分 类 号：TU375.3[建筑科学—结构工程] P315.92[天文地球—地震学]