多层混凝土小型空心砌块与煤矸石页岩多孔砖组合砌体模型楼动力性能实测与分析

对一个1：1比例的多层混凝土小型空心砌块与煤矸石页岩多孔砖组合砌体模型的抗震性能进行了试验研究。对该足尺试件在抗震性能试验的不同受力阶段进行了动力测试，分别得到了结构处于弹性、开裂、屈服和破坏状态下的频率、振型、阻尼等动力参数，分析了模型动力特性的变化特点及原因，为这种结构的抗震设计及动力分析提供了依据。     

装配式双钢套管内置高强混凝土组合剪力墙及其试验验证

提出一种适用于高层建筑的新型装配式双钢套管内置高强混凝土(FDSHC)组合剪力墙,并通过试验验证其抗震性能.通过6个两层 FDSHC组合剪力墙试件的压G弯G剪滞回试验和6个单层FDSHC组合剪力墙试件的拉G弯G剪滞回试验,分析试件的破坏特征和滞回性能,研究轴力、钢管混凝土截面含量比、偏心距、外钢管是否焊接对新型墙体抗震性能的影响.结果表明,FDSHC 组合剪力墙试件的破坏形态为弯剪复合破坏,其在压(拉)-弯-剪复合受力作用下具有较高的承载能力,滞回曲线饱满,耗能能力和整体装配性能良好.轴压比越大(轴拉比越小),峰值强度越高;偏心距越大,耗能能力越弱;钢管混凝土截面含量比和外钢管是否焊接的影响不明显.相对于传统装配式混凝土剪力墙,FDSHC组合剪力墙具有“易装配、高承载、低成本”的优点和优越的抗震性能,有望在装配式高层建筑中推广应用.     

带斜筋单排配筋L形截面剪力墙的非工程方向抗震性能1

带斜筋单排配筋混凝土剪力墙结构是为取代粘土砖多层住宅结构而发展起来的一种新型多层混凝土结构,其经济性合理,抗震性能优于传统的砌体结构.为进一步充分了解其抗震性能,开展该新型结构体系中“L”形截面剪力墙的非工程轴方向抗震性能试验研究.进行1个单排配筋混凝土“L”形截面剪力墙和1个带斜筋的单排配筋混凝土“L”形截面剪力墙低周反复荷载试验,对比分析其破坏特征、滞回特性、耗能能力、承载力、延性、刚度,并利用ABAQUS软件进行非线性有限元分析,探究斜筋对其抗震性能的影响.研究结果表明,在非工程轴方向,带斜筋单排配筋“L”形截面混凝土剪力墙的抗震性能优于不带斜筋的剪力墙.     

三层单排配筋剪力墙结构抗震性能试验研究

为了对双排配筋剪力墙和单排配筋剪力墙的抗震性能进行对比研究,本文设计了1个1／3缩尺的三层混凝土剪力墙结构模型,模型的一侧墙体为双向双排配筋,另一侧墙体为双向单排配筋。对其进行了低周反复荷载下的抗震性能试验研究,分析了其承载力、延性、刚度及其退化过程、滞回特性、耗能能力和破坏特征。研究表明：在墙体的配筋率相同情况下,由于单排配筋墙体钢筋的间距相对于双排配筋墙体钢筋间距小,其首先约束混凝土裂缝的几率更大,其平面内的抗震性能优于双排配筋剪力墙;由于剪力墙的翼缘和腹板共同工作,单排配筋剪力墙平面外的性能也可满足多层剪力墙结构设计的要求。     

钢管混凝土边框内藏带斜肋钢板中高剪力墙抗震性能试验

提出了钢管混凝土边框内藏斜撑肋钢板组合中高剪力墙.为研究这种组合剪力墙的抗震性能,进行了5个不同构造的中高剪力墙模型低周反复荷载试验.分析了试件的损伤特征、承载力、耗能、滞回特性,提出了正截面抗弯承载力计算模型,计算结果与试验符合较好.研究表明:钢管混凝土边框内藏钢板组合剪力墙具有较高的承载力和良好的耗能性能;钢管混凝土边框内藏带斜撑肋钢板中高剪力墙,适于在墙体厚度小于钢管尺寸或内藏钢板厚度较薄的“强边框、弱墙体”情况下应用,可明显减轻钢管混凝土边框底部的损伤,延缓墙体性能退化,提高组合剪力墙的抗震能力.     

带窗洞的加气混凝土砌块砌体墙抗震性能分析

为了研究设窗洞的蒸压加气混凝土砌块砌体承重墙的抗震性能,运用ABAQUS有限元分析软件对其进行了非线性分析。首先将有限元模型的计算结果与足尺试件的试验结果进行了对比验证,在此基础上,通过改变墙体的竖向压应力、水平配筋和开洞大小,研究了这些参数对墙体抗震性能的影响。研究表明:随着竖向压应力的增大,墙体水平承载力提高,而极限变形能力则有降低趋势;水平配筋可以提高墙体的承载力和变形性能;增大洞口水平尺寸导致极限承载力明显降低,而对其相应位移的影响则小得多。     

免蒸免烧粉煤灰多孔砖墙体抗震性能试验研究

免蒸压免烧结粉煤灰多孔砖是一种新型承重墙体材料。本文通过三片墙体低周反复荷载试验,系统研究了粉煤灰多孔砖墙体的力学性能和抗震性能,包括墙体的破坏特征、滞回曲线、刚度、延性、骨架曲线及受剪承载力等。试验结果表明,免蒸压免烧结粉煤灰多孔砖墙体的破坏形态与普通黏土砖墙体相似,主要呈剪切破坏;墙体具有较高的受剪承载力、延性和耗能能力,适宜在地震区村镇建筑中推广应用。     

新型节能复合混凝土空心砌块砌体抗震性能的试验研究

本文通过2片开窗洞加窗台梁节能复合混凝土小型空心砌块墙体和2片不开窗洞墙体的水平低周反复荷载试验,研究了节能复合混凝土小型空心砌块砌体墙的受力全过程、开裂部位、裂缝发展情况以及破坏形态,分析了墙体的滞回特性、延性、耗能能力,刚度退化曲线等抗震性能,同时,考察了墙体外叶保护层的受力性能、破坏程度以及与墙体的共同工作机理,探讨了不同构造措施以及开窗洞对墙体抗震性能的影响。研究结果表明:复合混凝土小型砌块砌体从开始加载到最终破坏,砌块保护层都没有明显的鼓凸和脱落现象,说明聚苯层及横向拉结筋能够提供可靠的连接,保证外叶保护层在水平剪力和竖向荷载共同作用下和墙体整体工作,此外,开窗洞对墙体的抗震性能削弱较大。     

多孔砖砌体开窗洞纵墙片的抗震性能研究

试验采用ＤＳ１,ＤＳ２型多孔砖砌体,模拟大开间设进深梁房屋的纵向开窗洞墙体。试件采用不同的窗洞尺寸,并在窗间墙处设置钢筋混凝土构造柱,部分墙片配有水平钢筋。试验结果表明,开窗洞纵墙片窗间墙处设钢筋混凝土构造柱以及加配水平钢筋可以增强纵墙的抗剪强度和变形能力,改善墙体的抗震性能。     

再生混凝土组合砌体非线性有限元分析

为研究再生混凝土组合砌体这一新型结构的抗震性能,在水平低周反复荷载试验基础上,利用ANSYS有限元分析软件建立再生混凝土组合砌体的有限元计算模型,并进行低周反复荷载下抗震性能有限元分析。分析结果表明:与普通砖砌墙体相比,再生混凝土组合砌体的抗震性能明显提高,且随着再生混凝土墙体比例的增加,再生混凝土组合砌体的抗震性能随之增加。并且分析结果还验证了ANSYS有限元分析软件对再生混凝土组合砌体分析的可行性。     

增设翼柱的底商多层砌体房屋抗震性能试验研究

为研究在结构前纵墙底层部位增设翼柱对底商多层砌体房屋抗倒塌性能的影响,分别设计了一个1/5缩尺比例的普通底商多层砌体房屋及增设翼柱的砌体房屋模型分别进行振动台试验研究,对比分析各模型的破坏过程、加速度放大系数、相对位移及典型位置应变等参数。结果表明,在同样的地震动输入下,带有翼柱的底商多层砌体房屋破坏程度、层间相对位移及层间位移角均明显低于普通底商多层砌体房屋,带有翼柱的底商多层砌体房屋抗倒塌性能显著提高。     

钢丝网灌浆(SRG)加固受损多层砌体墙体抗震性能试验研究

应用钢丝网灌浆加固技术（SRG）修复村镇砌体结构具有施工简单、造价低廉以及性能优越等优点。先对一多层砌体结构开洞墙体模型进行抗震性能拟静力试验,后采用SRG技术加固受损墙体再次进行同条件试验。对比分析了加固前后墙体的破坏现象、滞回性能、刚度退化规律、耗能特性、延性与变形特征等抗震性能。试验结果表明:采用SRG技术加固受损砌体结构的破坏模式更为合理,墙体承载力、变形性能及耗能特性亦可显著提升。研究结果揭示了SRG技术加固受损砌体结构的实效性,为其在村镇建筑加固领域的应用提供技术支持。     

应用ANSYS对夹层橡胶垫耗能低剪力墙结构的性能分析

本文针对低剪力墙结构延性差、耗能能力差、结构抗震性能差等问题，提出一种新型耗能低剪力墙结构，并应用有限元分析软件ANSYS对同截面整体墙结构及耗能墙结构进行了数值模拟计算，并对其破坏形态、耗能能力、承载力情况、变形性能等进行了对比分析。结果表明，夹层橡胶垫耗能低剪力墙结构具有良好的延性和抗震性能。     

墙体开洞影响下房屋砖砌体结构地震易损性分析

为获取可靠的墙体开洞影响下房屋砖砌体结构地震易损性分析结果,采用ABAQUS有限元分析软件构建房屋砖砌体结构墙体模型,设置合理的墙体模型参数和数值模拟参数;对比模拟数值与以往研究的测试值,证明所构建模型参数取值合理;将截取的峰值段江油地震波作为上述模型的地震动输入,根据测得的房屋砖砌体结构的力学变化数据,分析房屋砖砌体结构的地震易损性。分析结果表明:地震情况下,随着墙体开洞率的增加,墙体荷载能力下降、墙体水平承载力增长幅度降低、墙体相对刚度退化率增加;墙体开洞数量越多,房屋砖砌体结构侧向刚度下降越快。因此分析得出墙体开洞率大、墙体开洞数量多,房屋砖砌体结构的地震易损性越显著。     

双层打包带加固窗间墙抗震性能试验研究

地震时砌体结构窗间墙易发生破坏,为了提高其抗震性能,对高宽比为1的2组共4片墙体,其中:2片为双层打包带加固墙体,2片为原墙,进行了拟静力试验,研究墙体的破坏形态、水平承载力、滞回曲线和耗能等抗震性能。试验发现原墙发生剪切破坏,加固后墙体发生摇摆破坏,加固改变了墙体破坏模式,加固后墙体滞回曲线饱满但有捏笼,破坏荷载、延性和耗能能力都有提高,破坏时未发生剥离,表明双层打包带加固法有效地提高了窗间墙体抗震性能,对承受较大竖向应力墙体效果更好,建议加固时要加强加固层与窗下和窗上墙体的连接。     

Experimental and analytical studies on earthquake resisting behaviour of confined concrete block masonry structures

To improve the seismic performance of masonry structures, confined masonry that improves the seismic resistance of masonry structures by the confining effect of surrounding bond beams and tie columns is constructed. This study investigated the earthquake resisting behaviour of confined masonry structures that are being studied and constructed in China. The structural system consists of unreinforced block masonry walls with surrounding reinforced concrete bond beams and tie columns. The characteristics of the structure include: (1) damage to blocks is reduced and brittle failure is avoided by the comparatively lower strength of the joint mortar than that of the blocks, (2) the masonry walls and surrounding reinforced concrete bond beams and tie columns are securely jointed by the shear keys of the tie columns. In this study, wall specimens made of concrete blocks were tested under a cyclic lateral load and simulated by a rigid body spring model that models non‐linear behaviour by rigid bodies and boundary springs. The results of studies outline the resisting mechanism, indicating that a rigid body spring model is considered appropriate for analysing this type of structure. Copyright © 2006 John Wiley & Sons, Ltd.     

Seismic performance of masonry walls retrofitted with steel reinforced grout

An innovative solution for the seismic protection of existing masonry structures is proposed and investigated through shake table tests on a natural scale wall assemblage. After a former test series carried out without reinforcement, the specimen was retrofitted using Steel Reinforced Grout. The strengthening system comprises horizontal strips of ultra‐high strength steel cords, externally bonded to the masonry with hydraulic lime mortar, and connectors to transversal walls, applied within the thickness of the plaster layer. In order to assess the seismic performance of the retrofitted wall, natural accelerograms were applied with increasing intensity up to failure. Test results provide a deep understanding of the effectiveness of mortar‐based composites for improving the out‐of‐plane seismic capacity of masonry walls, in comparison with traditional reinforcements with steel tie‐bars. The structural implications of the proposed solution in terms of dynamic properties and damage development under earthquake loads are also discussed.Copyright © 2015 John Wiley & Sons, Ltd.     

西藏典型单层混凝土砌块房屋打包带加固抗震试验研究

本文以振动台试验方式研究了打包带加固对西藏典型单层混凝土砌块房屋抗震性能的影响,同时考虑了结构平面布置、抗震设防及砌筑质量三个因素。选取3种西藏地区民居的经典户型制作了7个1∶3缩尺模型进行振动台试验,模型分别为3个无打包带加固模型、3个有打包带加固模型以及1个加固一半的模型。试验结果表明打包带加固墙体能明显提高墙体的整体性,减轻墙体震损;无打包带加固但砌筑质量好的单层民居抗震能力较好,基本满足当地9度设防的要求;高烈度下平面布置不规则的结构容易因扭转作用而发生破坏,圈梁、构造柱也在高烈度下发挥较大作用。打包带加固技术作为一种经济实用的加固技术可在西藏地区进行推广。     

Pseudo-dynamic tests on masonry residential buildings seismically retrofitted by precast steel reinforced concrete walls

A retrofitting technology using precast steel reinforced concrete (PSRC) panels is developed to improve the seismic performance of old masonry buildings. The PSRC panels are built up as an external PSRC wall system surrounding the existing masonry building. The PSRC walls are well connected to the existing masonry building, which provides enough confinement to effectively improve the ductility, strength, and stiffenss of old masonry structures. The PSRC panels are prefabricated in a factory, significantly reducing the situ work and associated construction time. To demonstrate the feasibility and mechanical effectivenss of the proposed retrofitting system, a full-scale five-story specimen was constructed. The retrofitting process was completed within five weeks with very limited indoor operation. The specimen was then tested in the lateral direction, which could potentially suffer sigifnicant damage in a large earthquake. The technical feasibility, construction workability, and seismic performance were thoroughly demonstrated by a full-scale specimen construction and pseudo-dynamic tests.     

Seismic behavior of a partially grouted reinforced masonry structure: Shake-table testing and numerical analyses

In regions of low to moderate seismicity in North America, reinforced masonry structures are mostly partially grouted. The behavior of such structures under lateral seismic loads is complicated because of the interaction of the grouted and ungrouted masonry. As revealed in past experimental studies, the performance of partially grouted masonry (PGM) walls under in-plane cyclic lateral loading is inferior to that of fully grouted walls. However, the dynamic behavior of a PGM wall system under severe seismic loads is not well understood. In this study, a full-scale, one-story, PGM building designed for a moderate seismic zone according to current code provisions was tested on a shake table. It was shown that the structure was able to develop an adequate base shear capacity and withstand two earthquake motions that had an effective intensity of two times the maximum considered earthquake with only moderate cracking in mortar joints. However, the structure eventually failed in a brittle manner in a subsequent motion that had a slightly lower effective intensity. A detailed finite element model of the test structure has been developed and validated. The model has been used to understand the distribution of the lateral force resistance among the wall components and to evaluate the shear-strength equation given in the design code. The code equation has been found to be adequate for this structure. Furthermore, a parametric study conducted with the finite element model has shown that the introduction of a continuous bond beam right below a window opening is highly beneficial.