带窗洞的竖向分布钢筋不连接...整体式剪力墙的受力性能分析_宋晓滨.pdf

第 53 卷 第 5 期2023 年 3 月上建 筑 结 构Building StructureVol.53 No.5Mar.2023 DOI:10.19701/j.jzjg.20221381国家自然科学基金项目(52078360)。第第一一作作者者:宋晓滨,博士,教授,主要从事混凝土和木结构抗震性能研究,Email:xiaobins 。带窗洞的竖向分布钢筋不连接装配整体式剪力墙的受力性能分析宋晓滨1,蔡 琪1,肖绪文1,2,曹志伟1,李 厂3,张士前3(1 同济大学土木工程学院建筑工程系,上海 200092;2 中国建筑股份有限公司,北京 100029;3 中国建筑第八工程局有限公司,上海 200112)摘要:为探究带窗洞的竖向分布钢筋不连接装配整体式剪力墙(SGBL 装配整体式剪力墙)的受力性能,采用ABAQUS 软件建立 SGBL 装配整体式剪力墙精细化有限元模型。有限元模型采用 Cohesive 接触和弹簧单元模拟预制墙板与后浇混凝土的拼缝,模拟所得荷载-位移曲线及破坏模式与文献中试验结果均吻合良好。在此基础上,对比了带窗洞 SGBL 装配整体式剪力墙与带窗洞现浇剪力墙受力性能的差异,并讨论了轴压比和洞口偏心等参数对带窗洞 SGBL 装配整体式剪力墙的承载力和刚度的影响。结果表明:通过适当增加边缘现浇段竖向钢筋,带窗洞SGBL 装配整体式剪力墙可拥有等同带窗洞现浇剪力墙的承载力。此外,轴压比对两类开洞剪力墙受力性能影响均较小,洞口偏心对带窗洞 SGBL 装配整体式剪力墙的承载力影响较小,当洞口偏心率小于 20%时,洞口偏心对刚度的影响小于 8%。关键词:SGBL 装配整体式剪力墙;带窗洞剪力墙;竖向分布钢筋不连接;抗侧性能;有限元分析 中图分类号:TU318,TU398.2 文献标志码:A文章编号:1002-848X(2023)05-0030-06引用本文 宋晓滨,蔡琪,肖绪文,等.带窗洞的竖向分布钢筋不连接装配整体式剪力墙的受力性能分析J.建筑结构,2023,53(5):30-35.SONG Xiaobin,CAI Qi,XIAO Xuwen,et al.Study on mechanical behavior of monolithic assembled concrete shear wall with non-connected vertical distribution reinforcement and window openingJ.Building Structure,2023,53(5):30-35.Study on mechanical behavior of monolithic assembled concrete shear wall with non-connected vertical distribution reinforcement and window openingSONG Xiaobin1,CAI Qi1,XIAO Xuwen1,2,CAO Zhiwei1,LI Chang3,ZHANG Shiqian3(1 Department of Structural Engineering,College of Civil Engineering,Tongji University,Shanghai 200092,China;2 China State Construction Engineering Co.,Ltd.,Beijing 100029,China;3 China Construction Eighth Engineering Division Co.,Ltd.,Shanghai 200112,China)Abstract:To investigate the mechanical behavior of monolithic assembled concrete shear wall with non-connected vertical distribution reinforcement(SGBL monolithic assembly shear wall)and window opening,a refined finite element model was developed in ABAQUS software.In the finite element model,Cohesive contact and spring connector were adopted for simulating the nonlinear behavior of the joints between precast wall panels and post-cast concrete.The load-displacement curves and the failure patterns obtained from the numerical analysis are in good agreement with the test results in literature.Based on the numerical model,the differences of mechanical behaviors of SGBL monolithic assembled shear wall with window opening and cast-in-situ shear wall with window opening,and the influence of parameters such as the axial compression ratio and the eccentricity of the window opening on the bearing capacity and rigidity of the SGBL monolithic assembled shear wall with window opening was analyzed.The result shows that by appropriately increasing the vertical reinforcement in the cast-in-situ boundary elements of the SGBL monolithic assembled shear wall with window opening,the bearing capacity of the SGBL monolithic assembled shear wall with window opening can be close to that of cast-in-situ shear wall.In addition,the axial compression ratio has little effect on the mechanical behaviors of the two types of shear wall with window opening,and the eccentricity of the opening had little effect on the bearing capacity of SGBL monolithic assembly shear wall with window opening.For an eccentricity of opening less than 20%,the influence on the lateral stiffness of SGBL monolithic assembled shear wall with window opening is less than 8%.第 53 卷 第 5 期 宋晓滨,等.带窗洞的竖向分布钢筋不连接装配整体式剪力墙的受力性能分析Keywords:SGBL monolithic assembled shear wall;shear wall with window opening;non-connected vertical distribution reinforcement;lateral resistance behavior;finite element analysis 0引言 由于良好的抗侧性能和室内空间规整性,装配式混凝土剪力墙结构被广泛地应用在住宅建筑1。对于装配式混凝土剪力墙结构,预制构件之间的连接性能是其受力性能的一个关键因素。目前主要采用的连接方式是灌浆套筒或浆锚连接。研究2-3发现,在保证灌浆质量的前提下,灌浆套筒或浆锚的连接方法可以使装配式混凝土剪力墙结构具有等同现浇的抗震性能。然而,混凝土剪力墙结构一般需配置较多小直径钢筋,灌浆套筒或浆锚等连接工艺将显著增加施工工作量和经济成本、影响施工周期,且连接质量难以保证4-5。为此,研究人员对装配式混凝土剪力墙结构竖向钢筋的连接方法提出了各种改进建议,比如无粘结预应力连接6-7、双向单排钢筋连接8等方法,但仍未彻底解决该问题。有学者提出将预制墙板的竖向钢筋底部与下层剪力墙的竖向钢筋全部不设置连接措施,而利用边缘构件中的竖向钢筋实现上下楼层钢筋的连接。研究结果表明,该类剪力墙裂缝发展较不充分,耗能能力较差9-10。肖绪文等11提出将预制墙体内的竖向钢筋底部断开后,按照受弯承载力等效原则调整剪力墙两端现浇边缘构件内的竖向钢筋用量,形成竖向钢筋不连接装配整体式剪力墙结构(简称SGBL 装配整体式剪力墙结构)。其试验结果表明,SGBL 装配整体式剪力墙的承载力、刚度、耗能等性能与现浇剪力墙基本无差异。出于建筑使用功能的考虑,实践中往往需要在剪力墙上开设门窗洞口,此类洞口会削弱墙体的承载力和刚度。已有研究表明,开洞剪力墙受力性能的主要影响因素包括剪力墙洞口大小12、位置13、形状14和配筋方式15-16等。带门洞的竖向分布钢筋不连接装配式剪力墙试验表明17,预制墙板的竖向钢筋断开后,装配式开洞剪力墙与现浇开洞剪力墙的受力性能存在一定差异:装配式开洞剪力墙墙肢的裂缝集中分布于现浇边缘构件底部,洞口两侧的预制墙肢底部基本无裂缝开展,且预制墙板水平向拼缝未出现开裂滑移。带窗洞 SGBL 装配整体式剪力墙的预制墙板底部不需预埋灌浆套筒或预留浆锚孔洞,预制墙板侧面和顶面预留的胡子筋则可通过后浇混凝土与其他构件连接,如图 1 所示。当开设门窗洞口时,SGBL 装配整体式剪力墙形成仅现浇边缘构件有竖向钢筋连接的剪力墙墙肢。该剪力墙墙肢的预制部分由于竖向钢筋不连接而不能受拉,与传统开洞剪力墙墙肢有显著差异。目前关于带窗洞 SGBL 装配整体式剪力墙受力性能及其影响参数的研究较少。图 1 带窗洞 SGBL 装配整体式剪力墙结构示意本文基于 ABAQUS 分析软件建立带窗洞 SGBL装配整体式剪力墙有限元模型,采用 Cohesive 接触和弹簧单元模拟预制墙板与后浇混凝土之间的拼缝。基于带窗洞 SGBL 装配整体式剪力墙和未开洞剪力墙试验数据校核有限元模拟方法的合理性,在此基础上通过参数分析讨论墙肢轴压比和洞口偏心率(洞口中心距墙体中心距离与墙肢总长度一半的比值)等参数对带窗洞 SGBL 装配整体式剪力墙受力性能的影响。1有限元建模1.1 模型基本信息 本文中剪力墙有限元模型采用分离式建模,如图 2 所示。钢筋和混凝土分别采用 ABAQUS 的T3D2 单元和 C3D8R 单元进行模拟,模型所有实体单元均采用六面体网格划分。忽略钢筋和混凝土之间的粘结滑移,所有钢筋单元采用 Embedded 技术嵌入混凝土单元内,使两者共结点协同工作。图 2 带窗洞 SGBL 装配整体式剪力墙有限元模型13建 筑 结 构2023 年混凝土的单轴应力-应变关系则根据混凝土结构设计规范(GB 500102010)(2015 年版)建议的混凝土受拉及