| 引用本文: | 余琼,王子沁,白少华,范宝秀,张志,董经民,陈振海,宫鑫.套筒灌浆搭接接头拉伸试验及受力机理分析[J].哈尔滨工业大学学报,2021,53(4):96.DOI:10.11918/202006123 |
| YU Qiong,WANG Ziqin,BAI Shaohua,FAN Baoxiu,ZHANG Zhi,DONG Jingmin,CHEN Zhenhai,GONG Xin.Tensile test and stress mechanism analysis of grouted sleeve lapping connectors for rebars[J].Journal of Harbin Institute of Technology,2021,53(4):96.DOI:10.11918/202006123 |
|
| |
|
|
| 本文已被：浏览 871次 下载 736次 |
码上扫一扫！ |
|
|
| 套筒灌浆搭接接头拉伸试验及受力机理分析 |
|
余琼1,王子沁1,白少华2,范宝秀2,张志3,董经民2,陈振海3,宫鑫1
|
|
(1.同济大学 结构防灾减灾工程系,上海 200092;2.山西建筑工程集团有限公司,太原 030006;3.山西二建集团有限公司,太原 030013)
|
|
| 摘要: |
| 为研究钢筋套筒灌浆搭接接头的受力机理,进行了36个该接头拉伸试验,考察了其破坏形态、承载力、延性、套筒纵向及环向应变等。试验结果表明,当相对搭接长度相同时,试件的屈服、极限荷载随钢筋直径增大而提高；搭接长度越长,试件初始刚度、延性越好；加载前期套筒为纵向受拉、加载后期套筒纵向受压；随着搭接长度的增大,套筒纵向由拉变压的转换荷载逐渐增大；加载过程中近钢筋侧套筒纵向拉应变随着搭接长度增大而增大,极限荷载时远钢筋侧套筒纵向压应变随着搭接长度增大而变小；加载前期,套筒中部环向应变值大于边缘截面环向应变值；极限荷载时,由于端部灌浆料脱落,套筒边缘截面环向应变值小于中部截面环向应变值；细观分析了搭接接头的传力路径、力学机理,基于钢筋-混凝土黏结应力分布曲线,分析套筒纵向应力分布及发展过程,得出套筒加载前期为纵向受拉、加载后期为纵向受压,与试验结果吻合；基于试验数据,拟合出了接头极限黏结强度公式,提出套筒临界搭接长度公式。研究成果可为接头应用奠定理论基础。 |
| 关键词: 套筒约束 套筒纵向应变 拉-压转变 传力路径 临界搭接长度 |
| DOI：10.11918/202006123 |
| 分类号:TU375 |
| 文献标识码:A |
| 基金项目: |
|
| Tensile test and stress mechanism analysis of grouted sleeve lapping connectors for rebars |
|
YU Qiong1,WANG Ziqin1,BAI Shaohua2,FAN Baoxiu2,ZHANG Zhi3,DONG Jingmin2,CHEN Zhenhai3,GONG Xin1
|
|
(1.Department of Disaster Mitigation for Structures, Tongji University, Shanghai 200092, China; 2.Shanxi Construction Engineering Group Co. Ltd., Taiyuan 030006, China; 3.Shanxi Second Construction Group Co. Ltd., Taiyuan 030013, China)
|
| Abstract: |
| To study the stress mechanism of grouted sleeve lapping connectors for rebars with large diameters, a total of 36 lapping connectors were tested under uniaxial tensile load. The failure modes, bearing capacity, ductility, and sleeve strain of the connectors were investigated. Test results show that with the same relative lapping length, the yield strength and ultimate load of the specimens increased with the increase of the rebar diameter. Meanwhile, specimens with larger lapping lengths had better initial stiffness and ductility. At the early stage of loading, the sleeve was in longitudinal tensile state, and at the late loading stage, it was in longitudinal compression state. The conversion load of longitudinal sleeve strain from tension to compression increased gradually with increasing lapping length. With the increase of the lapping length, the longitudinal tensile strain of the sleeve near the rebar increased during the loading process, while the longitudinal compressive strain of the sleeve in the far side of the rebar decreased under ultimate load. At the early stage of the loading process, the circumferential strain in the middle of the sleeve was larger than that in the edge section. When the ultimate load was reached, the circumferential strain of the sleeve in the edge section was smaller than that in the middle section due to the shedding of the grout at the end of the specimens. The force transmission path and mechanical mechanism of the connectors were analyzed. The distribution and development of longitudinal sleeve stress were analyzed based on the curve of rebar-concrete bond stress, and results show that the sleeve was in longitudinal tensile state at the early stage of loading and in longitudinal compression state at the late loading stage, which was consistent with test results. The calculation formulas for the ultimate bond strength and critical lapping length of grouted sleeve lapping connectors were proposed based on the test data. The research lays theoretical foundations for the application of such connectors. |
| Key words: sleeve restraint longitudinal sleeve strain tension-compression transition force transmission path critical lapping length |
|
|
|
|
