方钢管石灰石机制砂再生粗骨料混凝土黏结滑移本构模型  

Bond-slip constitutive model of recycled coarse aggregate concrete with limestone manufactured sand in square steel tubes

作　　者：沙蒙 李祥 刘紫洋 管民生[1,2] SHA Meng;LI Xiang;LIU Ziyang;GUAN Minsheng(College of Civil and Transportation Engineering,Shenzhen University,Shenzhen 518060,Guangdong,China;Key Laboratory of Coastal Urban Resilient Infrastructures,Shenzhen University,Shenzhen 518060,Guangdong,China;Shenzhen Airport(Group)Co.,Ltd.,Shenzhen 518128,Guangdong,China)

机构地区：[1]深圳大学土木与交通工程学院,广东深圳518060 [2]深圳大学滨海城市韧性基础设施教育部重点实验室,广东深圳518060 [3]深圳市机场(集团)有限公司,广东深圳518128

出　　处：《建筑科学与工程学报》2023年第1期38-48,共11页Journal of Architecture and Civil Engineering

基　　金：国家自然科学基金重大项目(52090082)。

摘　　要：通过16根方钢管石灰石机制砂再生粗骨料混凝土试件推出试验,研究了机制砂再生粗骨料混凝土强度等级、石粉含量以及钢管宽厚比对方钢管石灰石机制砂再生粗骨料混凝土黏结性能的影响,结合试件自由端滑移曲线分析了黏结滑移发展过程与内在机理。对比了方钢管卵石机制砂再生粗骨料混凝土平均黏结强度,采用方钢管卵石机制砂再生粗骨料混凝土黏结滑移本构模型拟合得到了石灰石机制砂试件黏结滑移曲线,并与试验结果进行了对比验证。由于试件的黏结滑移性能受测点位置影响,通过引入位置函数,提出了能反映局部黏结滑移规律的黏结滑移本构模型。结果表明:方钢管石灰石机制砂再生粗骨料混凝土黏结滑移经历了胶结、滑移、摩阻力、后滑移4个阶段,且具有更高黏结强度;对比本构模型得到的计算值与试验值并分析其误差发现,采用方钢管卵石机制砂再生粗骨料混凝土黏结滑移本构模型拟合的黏结强度及滑移值与试验值相对误差均小于5%,且标准差小于0.05,证明该本构模型具有较好适用性。The push-out tests on 16 limestone manufactured sand recycled coarse aggregate concrete(MSRAC)-filled square steel tube specimens were conducted,and the influences of strength grade of MSRAC,stone powder content,and width-to-thickness ratio of steel tube on the bond-slip behavior between limestone MSRAC and square steel tube were investigated.Based on the free end slip curve of the specimen,the development process and internal mechanism of the bond-slip behavior were analyzed.The average bond strength was compared with that of pebble MSRAC-filled square steel tube.The bond-slip constitutive model of pebble MSRAC in square steel tube was employed to simulate the bond-slip curve of the limestone MSRAC in square steel tube and verified with the test results.The bond-slip behavior of the specimen was affected by the position of the measured point.By introducing the position function,a bond-slip constitutive model which can reflect the local bond slip law was proposed.The results show that limestone MSRAC-filled square steel tube has experienced four stages during the testing,including cementation,slipping,frictional resistance,and after-slipping,respectively,and it has higher bond strength comparing with that of pebble MSRAC.Comparing the calculated values with the test values obtained from the constitutive model and analyzing its error,it is found that the relative error between the bond strength and slip value fitted by the bond-slip constitutive model of pebble MSRAC in square steel tube and the test values is less than 5%,and the standard deviation is less than 0.05,which proves that the constitutive model has good applicability.

关 键 词：方钢管 石灰石机制砂 再生粗骨料混凝土 位置函数 黏结滑移本构模型 

分 类 号：TU317[建筑科学—结构工程]