HPB300级箍筋混凝土梁扭曲裂缝宽度试验研究  

Experimental study on torsional crack width of reinforced concrete beams with HPB300 stirrups

作　　者：乐风江[1,2] 顾兴华 云凤玲 赵文[1,2] 崔立平 YUE Fengjiang;GU Xinghua;YUN Fengling;ZHAO Wen;CUI Liping(School of Architecture and Engineering,Xinjiang University,Urumqi 830017,Xinjiang,China;Xinjiang Key Laboratory of Building Structure and Earthquake Resistance,Xinjiang University,Urumqi 830017,Xinjiang,China;Shandong Jianye Engineering Technology Co,Ltd.,Linyi 276005,Shandong,China)

机构地区：[1]新疆大学建筑工程学院,新疆乌鲁木齐830017 [2]新疆大学建筑结构与抗震重点实验室,新疆乌鲁木齐830017 [3]山东建业工程科技有限公司,山东临沂276005

出　　处：《建筑科学与工程学报》2023年第6期101-110,共10页Journal of Architecture and Civil Engineering

基　　金：新疆维吾尔自治区研究生创新项目(XJ2021G073);新疆建筑结构与抗震重点实验室开放课题(20200305)。

摘　　要：对11根混凝土梁(10根HPB300级钢筋配箍的混凝土梁和1根HRB400级钢筋配箍的混凝土梁)进行了扭曲裂缝宽度试验研究,探讨了纯扭作用下箍筋与纵筋的应变对混凝土梁裂缝分布和裂缝宽度的影响规律,分析了纵筋配筋率、箍筋配筋率与箍筋间距等因素与矩形截面混凝土纯扭构件裂缝宽度的相关性。结果表明:矩形截面混凝土纯扭构件的裂缝宽度与箍筋应变呈线性正比例增长,与箍筋间距、纵筋间距、截面高宽比直接相关,通过改变箍筋间距、纵筋间距改变配箍率、配筋率对扭曲裂缝宽度有较大影响;箍筋或纵筋的直径变化对矩形截面混凝土纯扭构件裂缝宽度的影响不大,在混凝土强度和截面高宽比相同的条件下,扭曲裂缝间距与总配筋率有关,总配筋率越大,裂缝间距越小;在适筋的配筋范围内,纯扭作用下裂缝倾角与配筋强度比没有明显关系;采用规范承载力公式设计的HPB300钢筋配箍的混凝土纯扭梁不能自然满足正常使用阶段最大裂缝宽度的限值要求。The torsional crack width test was carried out on 11 concrete beams(including 10 concrete beams with HPB300 steel stirrups and 1 concrete beam with HRB400 steel stirrups).The influence of the strain of stirrups and longitudinal reinforcement on the crack distribution and crack width of concrete beams under pure torsion was discussed.The correlation between the crack width of rectangular section concrete pure torsion members and the factors such as the ratio of longitudinal reinforcement,the ratio of stirrups and the spacing of stirrups was analyzed.The results show that the crack width of the rectangular section concrete pure torsion member increases linearly proportional to the stirrup strain,which is directly related to the stirrup spacing,longitudinal reinforcement spacing and section aspect ratio.By changing the stirrup spacing and longitudinal reinforcement spacing,the stirrup ratio and reinforcement ratio have a great influence on the width of the torsional crack.The diameter change of stirrup or longitudinal reinforcement has little effect on the crack width of rectangular section concrete pure torsion members.Under the same condition of concrete strength and section aspect ratio,the spacing of torsional cracks is related to the total reinforcement ratio.The larger the total reinforcement ratio,the smaller the crack spacing.In the range of suitable reinforcement,there is no obvious relationship between crack dip angle and reinforcement strength ratio under pure torsion.The concrete pure torsion beam with HPB300 steel stirrups designed by the standard bearing capacity formula cannot naturally meet the limit requirements of the maximum crack width in the normal use stage.

关 键 词：混凝土梁 纯扭试验 裂缝宽度 配箍率 箍筋间距 

分 类 号：TU528[建筑科学—建筑技术科学]