榫卯式接缝预制混凝土剪力墙受力性能试验研究

为研究榫卯式接缝预制混凝土剪力墙的受力性能,进行了1片现浇钢筋混凝土剪力墙和4片预制混凝土剪力墙在恒定轴力作用下的拟静力试验,分析了榫卯式接缝性能及墙体的抗震性能。结果表明：峰值荷载前,同一位置榫卯式接缝两侧水平钢筋应变基本相同,接缝两侧墙体基本无相对变形。破坏时水平、竖向相对变形仅为0.34、0.79mm,接缝连接可靠,保证了墙体的整体性能。榫卯式接缝预制混凝土剪力墙的受弯承载力、刚度与钢筋混凝土剪力墙基本相当,能够达到“等同现浇”的设计目标;破坏时墙体竖向接缝处混凝土剥落,减小了根部混凝土压溃区域面积,提高了墙体的变形能力;当顶点位移角为1/50时,预制混凝土剪力墙仍保持良好的竖向承载能力;提高边缘构件纵筋配筋率,墙体承载力提高,破坏区域更加集中在墙体的接缝处,延缓了根部混凝土的压溃。     

带现浇暗柱齿槽式预制钢筋混凝土剪力墙抗震性能试验

介绍了3片剪跨比为2.13的钢筋混凝土剪力墙试件在特定轴压比下的拟静力试验,其中1片为现浇试件CW-1,另外2片为采用预制墙板,两端暗柱与水平齿槽现浇混凝土在墙体底部实现与之连接的预制试件。预制试件的主要区别是一片在齿槽内不设竖向分布钢筋的试件PW-1,另一片齿槽内竖向分布钢筋自由搭接的试件PW-2。试验结果表明：通过齿槽连接的预制墙体,其破坏形态与现浇试件基本相同,墙体两端暗柱底部混凝土受压破坏、竖向钢筋受拉屈服;预制试件的极限位移角为1/48~1/53;齿槽式连接能够保证剪力墙在正常工作状态下的受剪承载力;预制试件PW-2的滞回曲线饱满,受剪承载力与现浇试件相当,其延性性能满足抗震要求,齿槽区域墙体竖向分布钢筋自由搭接的连接方式在一定轴压比下可行,经进一步的试验和分析研究后可推广应用。     

竖向钢筋采用不同连接方法的预制钢筋混凝土剪力墙抗震性能试验

介绍了5个剪跨比为2.25的钢筋混凝土剪力墙试件的拟静力试验,其中1个为现浇墙,4个为竖向钢筋采用不同连接方法的预制墙。试验结果表明：预制墙试件与现浇墙试件的破坏形态基本相同,为边缘构件竖向钢筋受拉屈服、墙底混凝土受压破坏;套筒浆锚连接能有效传递钢筋应力;套箍连接试件的预制墙与底部现浇部分发生面内错动,其极限位移角和耗能能力最小;预制墙试件的极限位移角大于1/100;轴压力作用下的正截面承载力试验值大于现行规范公式计算值。根据试验结果,提出了预制剪力墙需进一步研究的建议。图13表6参5     

竖向分布钢筋单排间接搭接的带现浇暗柱预制剪力墙抗震性能试验

为进一步研究竖向分布钢筋与单排布置的连接钢筋间接搭接、连接钢筋采用直螺纹套筒灌浆连接的带现浇暗柱预制剪力墙抗震性能,完成了5个试件的拟静力试验,其中3个试件一端带暗柱,2个试件两端带暗柱。试验结果表明,现浇暗柱与预制剪力墙作为整体共同工作,试件以水平裂缝及其延伸的斜裂缝为主,墙底与地梁之间产生水平通缝,达到承载力前竖向钢筋受拉屈服,墙底混凝土压碎,破坏形态为压弯破坏;可采用现行规范公式计算预制剪力墙的压弯承载力,且考虑竖向分布钢筋的作用;试件的极限位移角达1/99～1/62。     

不同榫卯板构造的装配整体式剪力墙抗震性能试验研究

对1个现浇钢筋混凝土剪力墙试件和2个装配整体式剪力墙剪力墙试件进行拟静力试验,研究剪跨比为1.5的装配整体式剪力墙的抗震性能以及榫卯板构造对榫卯接缝的连接性能的影响.结果 表明:榫卯接缝整体性良好,接缝开裂时试件位移角远大于1/1000;装配整体式剪力墙的破坏区域主要集中在榫卯接缝处,峰值荷载时墙体根部混凝土基本完好,承载力低于现浇钢筋混凝土剪力墙,但刚度退化速率小于现浇钢筋混凝土剪力墙,变形能力、累计耗能大于现浇钢筋混凝土剪力墙,峰值荷载后装配整体式剪力墙进入墙柱组合体受力阶段,承载力下降减缓,位移角达到1/25时仍保持水平和竖向承载力;榫卯板横向凹槽底部与竖向孔洞内侧是否平齐对墙体承载力基本没有影响,但平齐构造可延缓榫卯接缝破坏,有助于提高墙体的刚度和耗能能力.     

钢筋套筒挤压搭接连接预制空心楼板-叠合梁节点试验

为研究受拉钢筋套筒挤压搭接连接的预制空心楼板-叠合梁连接节点在竖向荷载作用下的受力性能,进行了2个筒芯内模布设方向不同的预制空心楼板-叠合梁连接节点和1个现浇空心楼板-叠合梁连接节点的静力试验。结果表明:3个试件的裂缝分布相同、破坏形态相同,均为空心楼板受弯破坏;试件的试验承载力与规范计算承载力的比值均大于1.05,可采用规范正截面受弯承载力公式计算预制空心楼板的受弯承载力;试件的名义屈服荷载、峰值荷载、峰值点割线刚度基本相同;预制空心楼板受拉钢筋套筒挤压搭接接头可有效传递钢筋拉力。     

预应力预制混凝土剪力墙抗震性能试验研究

通过后张拉高强无黏结预应力筋将分段预制墙板拼装成整体预应力预制混凝土剪力墙,剪力墙根部靠近中间位置布置若干普通钢筋以增加墙体耗能性。为比较该类剪力墙与现浇混凝土剪力墙的抗震性能,进行了3片预应力预制混凝土剪力墙和1片现浇混凝土剪力墙的拟静力试验,研究墙体的破坏过程及破坏形态、滞回及骨架曲线、位移延性、耗能能力、刚度退化、残余位移等。结果表明：预应力预制混凝土剪力墙的非线性变形集中在墙根部接缝处,导致墙体本身的损伤较小;预应力筋可提供恢复力,能有效减小残余变形;由于耗能钢筋的锚固失效,预制混凝土剪力墙的滞回曲线不如现浇混凝土剪力墙试件饱满;刚度退化早于现浇墙体,但下降段曲线较现浇墙体平缓,其刚度退化较现浇墙体缓慢;锚固失效是由耗能钢筋过密布置导致。     

楔形节点现浇连接的装配式钢筋混凝土剪力墙抗震性能研究

为了研究楔形节点现浇连接的装配式钢筋混凝土剪力墙的抗震性能,对剪跨比为2.1的装配式钢筋混凝土剪力墙试件进行足尺拟静力试验,并与相同尺寸的现浇墙体试件进行对比。试验结果表明,预制墙试件与现浇墙试件的破坏形态基本相同,为竖向钢筋受拉屈服、墙底混凝土受压破坏;预制墙试件的极限位移角为1/69,比现浇墙试件略小,开裂荷载与承载力均小于现浇墙试件;预制墙试件的滞回曲线较饱满,其延性性能满足抗震要求。并利用有限元分析软件ABAQUS对此楔形节点现浇连接的装配式钢筋混凝土剪力墙进行了数值模拟,将模拟结果与试验结果进行对比,模拟得到的承载力、侧移均与试验结果接近,两个方法得到的骨架曲线也基本吻合。     

接缝形式对凹槽浆锚连接装配式混凝土剪力墙抗震性能影响研究

为研究不同接缝形式（水平接缝、竖向接缝、竖向和水平接缝）的凹槽浆锚连接预制混凝土剪力墙抗震性能,完成1片现浇剪力墙和3片不同接缝形式的预制剪力墙拟静力加载试验,分析了不同接缝形式对预制墙体破坏过程、破坏特征、滞回性能、承载力、延性等的影响。试验结果表明：4片墙体的破坏形式均为受弯破坏;水平接缝装配式剪力墙在峰值荷载前受力性能与现浇剪力墙基本相似,峰值荷载后随着水平接缝处结合面的开裂,水平接缝装配式剪力墙承载力和刚度退化较快;竖向接缝装配式剪力墙抗震性能总体上符合规范GB 50011—2010抗震要求,其延性略低于现浇剪力墙,且预制墙体竖向接缝的后浇部分利于结构的耗能;同时采用竖向和水平接缝装配式剪力墙的峰值荷载与竖向接缝剪力墙的基本一致,而极限位移较现浇剪力墙的低27%,其竖向接缝后浇部分的钢筋配筋率影响剪力墙的承载力。     

预制空心板剪力墙抗震性能试验研究

装配整体式空心板剪力墙结构(EVE)采用钢筋间接搭接实现上下层预制墙、同层相邻预制墙的连接。通过3个空心板剪力墙的拟静力试验,研究钢筋间接搭接、接缝构造、灌孔构造边缘构件的可行性。结果表明：竖向孔、水平孔内连接钢筋与对应的空心板内竖向、水平钢筋同一位置应变随水平力的变化规律相同,空心板剪力墙边缘构件竖向钢筋、竖向接缝水平钢筋间接搭接可依靠桁架机制有效传递钢筋拉压力;试件均实现了预期的破坏模式,竖向孔、水平孔内后浇混凝土可与空心板共同工作;压剪破坏的空心板剪力墙受剪承载力试验值为JGJ 3—2010《高层建筑混凝土结构技术规程》(简称《高规》)现浇剪力墙公式计算值的1.77倍,压弯破坏的空心板剪力墙受弯承载力试验值为《高规》现浇剪力墙公式计算值的1.15~1.23倍,可按《高规》现浇剪力墙斜截面受剪承载力、正截面受压承载力计算方法计算EVE空心板剪力墙的承载力;空心板剪力墙极限位移角为1/66~1/54,满足罕遇地震作用下剪力墙结构弹塑性变形能力的要求;灌孔边缘构件可采用全预制构造(竖向钢筋间接搭接,箍筋布置于空心板内)代替半预制构造(竖向孔内竖向钢筋贯通,箍筋布置于竖向孔内);空心板剪力墙水平接缝具有良好的抗滑移能力。     

复合齿槽U型筋搭接连接装配式剪力墙抗震性能试验研究

复合齿槽U型筋搭接连接装配式混凝土剪力墙由预留复合齿槽区预制墙体、暗柱及上下层墙体U型筋连接节点组成。为研究该装配式剪力墙的抗震性能,通过1个现浇和3个预制剪力墙试件的低周反复加载试验,对比分析了各剪力墙的破坏形态、滞回特性、承载力、延性、刚度退化和钢筋应变。结果表明：所有剪力墙破坏形态均为暗柱纵筋压屈、墙体两侧底部混凝土压碎剥落的压弯破坏;采用双填料口能够保证复合齿槽后浇区混凝土的密实度,复合齿槽区形成的暗梁对墙体底部具有强化作用;剪力墙竖向分布钢筋采用U型筋在复合齿槽区搭接连接能够有效传递钢筋应力;相同轴压比条件下,预制剪力墙承载力约为现浇剪力墙的90%;预制剪力墙的极限位移角为1/72~1/51,平均位移延性系数均大于5;同一位移下,预制剪力墙的累积耗能略大于现浇剪力墙。可采用GB 50010—2010中建议公式计算复合齿槽U型筋搭接连接装配式剪力墙的压弯承载力,计算结果偏于安全。     

预制混凝土空心模剪力墙受力性能试验研究

通过1个钢筋混凝土剪力墙试件和5个横向孔洞为矩形的预制混凝土空心模剪力墙试件的拟静力试验,研究了采用纵向孔洞为圆形、横向孔洞为矩形的空心模构造的预制混凝土空心模剪力墙试件的受力性能。结果表明：该预制混凝土空心模剪力墙沿竖向分布钢筋位置出现竖向裂缝,避免了脆性破坏发生,位移延性系数为3.87~6.47,变形性能良好;现浇与预制混凝土结合面是墙体受力的薄弱部位,降低了墙体的受剪承载力,对高轴压比试件尤为显著;空心模剪力墙在正常使用阶段的刚度与现浇混凝土剪力墙相似,在设计计算时无需对刚度进行折减;提高轴压比和减小剪跨比能够增加墙体的初始刚度,但加快了后期刚度退化速率;降低水平钢筋配筋量对墙体的受剪承载力和变形能力影响较小,但降低了开裂荷载,增加了裂缝宽度。     

Experimental study of L‐shaped precast RC shear walls with middle cast‐in‐situ joint

Precast shear walls, as an environmentally friendly building system, have been vigorously developed in China. There are many vertical and horizontal joints on precast reinforced concrete shear wall system, which certainly have a significant effect on seismic performance of structures. In this paper, 3 L‐shaped precast reinforced concrete shear walls that were assembled by 2 precast parts through a middle cast‐in‐situ joint and a compared 1 completely cast‐in‐situ were tested under low frequency cyclic loading to investigate their seismic behaviors. The vertical distributed reinforcements in the three precast specimens were equivalently spliced by grouting sleeves arranged along the center line of the wall, and the horizontal reinforcements were directly anchored in cast‐in‐situ joints. The experimental results, including failure mode, yielding load and displacement, skeleton curve, energy dissipation, stiffness degradation, ductility, and so forth were presented in the paper. The results show that the precast specimens have similar bearing capacity whereas much better deformation capacity and ductility compared to the cast‐in‐situ specimen. Additionally, the experimental results of ultimate shear capacity of specimens were also compared with that of the calculation results. These results indicate that the tested precast shear walls have good and reliable seismic performance and can be used as a structural member in engineering projects.     

装配式空心板剪力墙结构叠合连梁抗震性能试验研究

装配式空心板剪力墙结构的叠合连梁由预制U形混凝土模壳、模壳内后浇混凝土及水平后浇带组成。为研究其抗震性能,完成了3种跨高比、底部纵筋在墙肢内2种锚固方式并按“强剪弱弯”设计的5个连梁试件的拟静力试验,其中,跨高比为1.5和3.0的连梁试件各2个,跨高比为2.4的连梁试件1个,3个试件连梁底部纵筋锚固板锚固,2个试件连梁底部纵筋直线锚固。试验结果表明：预制U形模壳与后浇混凝土整体共同工作;达到峰值弯矩前,连梁纵筋屈服,箍筋未屈服,连梁与墙肢结合面开裂和滑移;加载结束时,连梁角部混凝土压坏、剥落;连梁为弯曲滑移破坏,但跨高比为1.5和2.4的连梁表面布满斜裂缝,跨高比为3.0的连梁的斜裂缝分布在两端约500mm高度范围内;连梁梁端弯矩-转角滞回曲线捏拢,耗能能力较差;连梁极限转角为1/40~1/28,具有很好的弹塑性变形能力;底部纵筋在墙肢内的锚固方式对连梁的抗震性能基本没有影响;连梁顶部纵筋受拉与底部纵筋受拉时的受弯承载力分别为按GB 50010—2010《混凝土结构设计规范》中的正截面受弯承载力公式计算值的1.10~1.34倍和1.13~1.37倍,可采用GB 50010—2010《混凝土结构设计规范》的公式计算叠合连梁的受弯承载力。     

Experimental study on seismic performance of L‐shaped partly precast reinforced concrete shear wall with cast‐in‐situ boundary elements

In order to promote industrial production of reinforced concrete shear wall, a typical partly precast reinforced concrete shear wall with both end boundary elements cast‐in‐situ and the other part precast is experimentally studied. In this paper, three L‐shaped specimens of this kind and one completely cast‐in‐situ specimen as a control group are tested under low‐frequency cyclic loading to investigate their safety, applicability, and different characteristics. For the partly precast specimen, the vertical distributed reinforcements of precast part are equivalently spliced by grouting sleeves arranged along the center line of the wall whereas the horizontal reinforcements are directly anchored into the cast‐in‐situ boundary elements. During the test, the axial compression ratio of these specimens is fixed at 0.2, 0.3, and 0.5, respectively. Such test phenomena and test data including failure modes, yielding load and displacement, the skeleton curve, energy dissipation, stiffness degradation, ductility, and so on are observed, analyzed, and compared. Chinese code and American Concrete Institute code are adopted to estimate the bearing capacity. Results show that the partly precast specimens have good integrity. With the increase of axial compression ratio, the bearing capacity of these partly precast specimens increases whereas the ductility decreases. It is also found that the partly precast specimens have slightly lower bearing capacity compared with the cast‐in‐situ specimen as well as excellent deformation capacity and ductility, which indicates the tested partly precast shear wall has good and reliable seismic performance and can be used as a structural element in building construction.     

Experimental study of lateral load behavior of H‐shaped precast reinforced concrete shear walls with bolted steel connections

This paper presents an experimental study of H‐shaped precast reinforced concrete shear walls involving vertical connections under combined vertical and lateral loading. The H‐wall is composed of two prefabricated flange wall panels: one prefabricated web wall panel and vertical bolted steel connections between the flange and web panels. The assembling of the H‐wall is completely dry without any in situ casting. Three H‐wall specimens were constructed and tested to investigate the mechanical behavior and seismic performance of them. The lateral load‐bearing capacity, ductility, energy dissipation, lateral stiffness, strain in the connecting steel frame, and sliding within the bolted steel connections are presented and discussed to evaluate the effectiveness of the vertical connections. The ultimate shear‐resistance mechanism of the precast H‐wall assembly is also analyzed. The H‐wall assemblies generally possess high load‐bearing capacity, favorable ductility, and good energy‐dissipating capacity. The thickness of the steel plates in the connecting steel frame affects the lateral stiffness and the ultimate load‐bearing capacity of the H‐walls. Furthermore, the encasing steel plates for the web wall panel not only helps transfer the stress in the wall steel bars but also confines the concrete resulting in improved ductility.     

Experimental study on shear behavior of two‐way hollow core precast panel shear wall with vertical connection

The two‐way hollow core precast panel (TWHCPP) exhibits good seismic performance. In this study, the shear behavior of the TWHCPP shear wall with vertical connections was investigated. Specifically, five shear wall specimens, which comprised one cast‐in‐place shear wall, one TWHCPP shear wall without vertical connections, and three TWHCPP shear walls with vertical connections, were investigated experimentally. The TWHCPP shear walls were also modeled through numerical simulation. The experimental and numerical results indicate that the TWHCPP shear wall specimens with vertical connections exhibit monolithic load‐bearing mechanisms before the peak point, which is similar to the cast‐in‐place shear wall specimen. When the peak point of the TWHCPP shear wall specimen was attained, vertical slits were formed in the vertical connection and major vertical crack regions, which divided the shear wall panel into multiple vertical concrete straps. Subsequently, the load‐bearing mechanism of the TWHCPP shear wall transformed to multiple vertical concrete straps working cooperatively with transverse reinforcements. Therefore, the brittle diagonal tension failure mode could be avoided, and a good hysteretic performance could be achieved. The outcomes of this study are expected to provide a useful reference for the application of the TWHCPP shear wall.     

环筋扣合锚接连接预制剪力墙抗震性能试验研究

对15个混凝土剪力墙试件进行低周反复荷载试验,研究环筋扣合锚接连接预制剪力墙的抗震性能,考察不同连接形式、不同钢筋配置、不同轴压比等参数影响下剪力墙试件的承载力、滞回特性及破坏机理。试件按纵筋直径和混凝土强度等级的不同分为3组,每组包括2个现浇试件（1个为钢筋贯通连接,1个为纵筋搭接连接）和3个采用环筋扣合锚接连接现浇带的预制试件（其中1个为箍筋加密试件）。试验结果表明：预制剪力墙试件与现浇试件的破坏模式一致,均为压弯破坏;箍筋加密预制剪力墙试件的极限位移角在1/82~1/50之间,其承载力、耗能、延性等性能与全预制试件基本相同,环筋扣合锚接连接剪力墙试件具有良好的抗震性能,可以用于装配式剪力墙结构的建造。     

Experimental study on seismic performance of L‐shaped insulated concrete sandwich shear wall with a horizontal seam

A series of new L‐shaped insulated concrete sandwich shear walls integrated with heat preservation function are tested for its seismic performance. Those specimens, partially excavated and filled with insulation materials, are made up of three precast specimens and one cast‐in‐situ specimen as a control group. For the three precast specimens, the vertical distributed reinforcements are equivalently spliced to the bottom beam by grouting sleeves arranged along the centerline of the wall, whereas for the compared specimen, they are directly cast‐in‐situ anchored. These specimens are tested under low frequency cyclic loading. The failure mode, yielding load and displacement, skeleton curve, energy dissipation, stiffness degradation, ductility, and so forth, are recorded and analyzed. The result shows that the precast specimens have similar bearing capacity and much better deformation capacity and ductility than that of the control group in this experiment. This indicates that the seismic performance of the proposed L‐shaped insulated concrete sandwich shear wall is desirable and generally meets the requirements of both function and safety, thus can be used as structural elements in practice. The methods in Chinese design code and American Concrete Institute code are adopted to calculate the ultimate shear capacity of this precast insulation shear wall, and it is found that the tested result is larger than the calculated one, indicating the calculation method is reliable.