Experimental Research on Anchorage Performance of Rebars Considering Mechanical Characteristics of RC Beam-Column Joints
-
摘要: 强烈地震作用下梁纵筋在钢筋混凝土梁柱节点内一般会产生明显的黏结滑移变形,通过合理的材料本构模型正确描述节点内梁纵筋的黏结滑移规律是节点单元有限元模型的关键问题。在"超级节点"单元模型和OpenSees软件中,梁纵筋的应力-滑移本构模型是在传统单根钢筋锚固的单调受拉试验基础上建立的,未考虑轴压力、循环拉压等对节点内梁纵筋受力的影响。对11个锚固钢筋试件在单调受拉、循环拉压等加载方式下的受力性能进行了试验,测量了钢筋的黏结滑移变形,通过对比锚固钢筋的应力-滑移试验结果,分析了加载方式、轴压力、相对锚固长度、钢筋屈服强度等对滑移变形的影响。研究结果表明,单调受拉时钢筋的锚固性能相对最好,拉-拉循环加载时锚固钢筋的黏结滑移变形更大,拉-压循环加载会进一步加大锚固钢筋的滑移变形;施加轴压力有利于提高锚固钢筋的黏结性能、减小黏结滑移变形;增加钢筋的相对锚固长度,钢筋受拉屈服时的滑移变形将减小;基于锚固钢筋的单调受拉试验建立的材料本构模型未考虑轴压力、加载方式的影响,难以合理模拟节点内梁纵筋在强烈地震作用下的滑移变形。Abstract: The longitudinal steel bars of beams generally produce a obvious bond-slip deformation in reinforced concrete (RC) beam-column joints under strong earthquake excitation. The key issue of finite element model of RC joint is to correctly describe the bond-slip laws of longitudinal steel bars of beams based on a reasonable material constitutive model. In the "super joint" model and OpenSees software platform, the stress-slippage constitutive model for longitudinal steel bars of beams was established on the basis of monotonic tensile test for traditional anchorage of single steel bars, the influence of axial compression and cyclic tension-compression on the anchorage performance of the longitudinal steel bars of beams in the joint was not considered. The mechanical properties of 11 specimens were tested under monotonic tension or cyclic tension-compression, and the bond-slip deformations of the bars were measured. By comparing the stress-slippage test results of the anchorage steel bars, the effects of loading method, axial compression, relative anchorage length and yield strength of the steel bars on the slip deformation were analyzed. The results showed that the anchorage performance of the steel bars was relatively the best under monotonic tension, the bond-slip deformation of the steel bars was larger under tension-tension cyclic loading, and the slip deformation of the steel bars would be further increased under tension-compression cyclic loading. The application of axial compression load was beneficial to improve the bond performance of the steel bar, and reduce the bond-slip deformation. With the increase of the relative anchorage length, the slip deformation of the steel bars at the tensile yield would decrease. The material constitutive model based on the monotonic tensile test of anchorage steel bar did not consider the influence of axial compression and loading method, it was difficult to reasonably simulate the slip deformation of longitudinal steel bars of beams in RC joints under strong earthquake.
-
Key words:
- beam-column joint /
- longitudinal steel bar /
- bond-slip /
- axial compression /
- loading method /
- finite element model
-
[1] ZHAO B,TAUCER F,ROSSETTO T.Field investigation on the performance of building structures during the 12 May 2008 Wenchuan earthquake in China[J].Engineering Structures,2009,31:1707-1723. [2] 霍林生,李宏男,肖诗云,等.汶川地震钢筋混凝土框架结构震害调查与启示[J].大连理工大学学报,2009,49(5):718-723. [3] HU B,KUNDU T.Seismic performance of interior and exterior beam-column joints in recycled aggregate concrete frames[J].Journal of Structural Engineering,2019,145(3).DOI:10.1061/(ASCE) ST.1943-541X.0002261. [4] YANG H,ZHAO W T,ZHU Z Z,et al.Seismic behavior comparison of reinforced concrete interior beam-column joints based on different loading methods[J].Engineering Structures,2018,166:31-45. [5] 吕西林,郭子雄,王亚勇.RC框架梁柱组合件抗震性能试验研究[J].建筑结构学报,2001,22(1):2-7. [6] SOLEIMANI D,POPOV E P,BERTERO V V.Hysteretic behavior of reinforced concrete beam-column subassemblage[J],ACI Journal,1979,76(11):1179-1195. [7] 傅剑平.钢筋混凝土框架节点的抗震性能与设计方法[D].重庆:重庆建筑大学,2002. [8] 赵雯桐.考虑节点区非弹性变形特征的RC梁柱节点抗震性能试验及有限元模型研究[D].重庆:重庆大学,2019. [9] OTANI S.Inelastic analysis of RC frame structures[J].Journal of the Structural Division,ASCE,1974,100:1433-1449. [10] BIRELY A C,LOWES L N,LEHMAN D E.A model for the practical nonlinear analysis of reinforced-concrete frames including joint flexibility[J].Engineering Structures,2012,34:455-465. [11] 杨红,莫林辉,陈进可,等.钢筋混凝土梁柱节点区非弹性变形的改进模型研究[J].建筑结构学报,2014,35(3):128-137. [12] ELMORSI M,KIANOUSH M R,TSO W K.Modeling bond-slip deformations in reinforced concrete beam-column joints[J].Canadian Journal of Civil Engineering,2000,27:490-505. [13] YOUSSEF M,GHOBARAH A.Modelling of RC beam-column joints and structural walls[J].Journal of Earthquake Engineering,2001,5(1):93-111. [14] SHIN M,LAFAVE J M.Testing and modelling for cyclic joint shear deformations in RC beam-column connections[C]//Proceedings of the 13th World Conference on Earthquake Engineering.Vancouver:2004. [15] LOWES L N,ALTOONTASH A.Modeling reinforced-concrete beam-column joints subjected to cyclic loading[J].Journal of Structural Engineering,ASCE,2003,129(12):1686-1697. [16] MITRA N,LOWES L N.Evaluation,calibration,and verification of a reinforced concrete beam-column joint model[J].Journal of Structural Engineering,ASCE,2007,133(1):105-120. [17] MAZZONI S,MCKENNA F,SCOTT M H,et al.Open system for earthquake engineering simulation users command-language manual[M/OL].University of California,Berkeley.2021.http://opensees.berkeley.edu/wiki/index.php/Command_Manual. [18] MITRA N,MITRA S,LOWES L N.Probabilistic model for failure initiation of reinforced concrete interior beam-column connections subjected to seismic loading[J].Engineering Structures,2011,33:154-162. [19] HWANG S J,LEE H J.Analytical model for predicting shear strengths of exterior reinforced concrete beam-column joints for seismic resistance[J].ACI Structural Journal,1999,96(5):846-857. [20] MITRA N.An analytical study of reinforced concrete beam-column joint behavior under seismic loading[D].Washington:Department of Civil Engineering,University of Washington,2007. [21] 董俊宏,杨红,赵雯桐.基于裂缝分布特征的RC框架中间节点受剪性能计算拉压杆模型[J].振动与冲击,2019,38(24):48-55. [22] 赵雯桐,杨红,傅剑平,等.梁柱节点的单元模型校准与其组合体试验方法对比[J].建筑结构学报,2017,38(5):133-142. [23] 中华人民共和国住房和城乡建设部.混凝土结构设计规范:GB 50010-2010[S].北京:中国建筑工业出版社,2010. [24] ELIGEHAUSEN R,POPOV E P,BERTERO V V.Local bond stress-slip relationships of deformed bars under generalized excitations:EERC Report No.83/23[R].Berkeley:Univ.of California,1983. [25] 徐有邻.变形钢筋-混凝土黏结锚固性能的试验研究[D].北京:清华大学,1990. [26] 赵羽习,金伟良.钢筋与混凝土黏结本构关系的试验研究[J].建筑结构学报,2002,23(1):32-37.
点击查看大图
计量
- 文章访问数: 141
- HTML全文浏览量: 33
- PDF下载量: 3
- 被引次数: 0