箍筋约束混凝土单轴受压损伤特性试验研究  

Experimental Research on Damage Characteristics of Stirrup-Confined Concrete Under Uniaxial Compression

作　　者：张油军 曾家俊 蒋振 廖日 李红豫 张璐 范懿文 ZHANG Youjun;ZENG Jiajun;JIANG Zhen;LIAO Ri;LI Hongyu;ZHANG Lu;FAN Yiwen(Ruiyu Construction Company Technology Co.,Ltd.,Nanning 530225,China;School of Civil Engineering,Guilin University of Technology,Guilin 541004,China;The First Construction Engineering Group Co.Ltd.of Guangxi Construction,Nanning 530001,China)

机构地区：[1]广西瑞宇建筑科技有限公司,南宁530225 [2]桂林理工大学土木工程学院,广西桂林541004 [3]广西建工第一建筑工程集团有限公司,南宁530001

出　　处：《工业建筑》2024年第9期100-107,共8页Industrial Construction

基　　金：国家自然科学基金项目(52168068,52068015)。

摘　　要：针对箍筋约束混凝土的损伤特性,设计了多组试验,通过单轴受压试验,对比分析了加载速率、混凝土强度、箍筋直径、体积配箍率等因素对约束混凝土试块力学性能和损伤特性的影响。通过试验结果表明:1)随着加载速率的增加,混凝土试块弹性变形阶段缩短,整个损伤过程塑性减弱,脆性增强。低加载速率下,混凝土试块主要是局部破坏和剪切破坏,当加载速率较快时,主要发生纵向劈裂;2)提高箍筋的屈服强度相当于增加混凝土损伤过程中的侧面围压,对约束混凝土试块的损伤起到一定的抑制作用;3)随着体积配箍率的增加,箍筋对混凝土试块损伤过程的约束作用越明显,有效抑制了试块的损伤演化过程。4)较高强度的混凝土试块在轴压过程中表现出更强的脆性,裂缝开展更快,适当增大混凝土强度有利于与箍筋相互配合抑制损伤演变。The experiments were designed for the characterizing the damage progress in the stirrup confined concrete.Through the uniaxial compression test,the parametric study was conducted to investigate the effects of loading rate,concrete strength,stirrup diameter,volume stirrup ratio on the mechanical properties and damage behaviors of the confined concrete.The experimental results were analyzed and demonstrated that:1)with the increase of loading rate,the elastic deformation stage of concrete is shortened;and the plasticity of the whole damage process is weakened;moreover,the damage shows more brittle patterns.At low loading rate,the local failure and shear failure were mainly observed.When the loading rate is reaching at a high level,the longitudinally splitting mainly occurs.2)Increasing the yield strength of stirrups is equivalent to the enhancement of the lateral confining pressure during the damage process of concrete,which plays an essential role in restraining the damage of the sample;3)With the increase of stirrup ratio,the confinement effect of stirrups on the damage process is becoming more obvious,which effectively constrains the damage evolution process.4)The samples with higher strength concrete show more brittle behavior and faster crack development during axial compression.Appropriate increase of concrete strength is beneficial to cooperative work with stirrups to restrain the evolution of damage.

关 键 词：混凝土 强度 箍筋约束 体积配箍率 损伤演变 

分 类 号：TU37[建筑科学—结构工程]