面内荷载作用下低屈服点钢板剪力墙的试验研究

进行面内荷载作用下低屈服点钢板剪力墙的试验研究。在低屈服点钢板剪力墙结构中,钢板墙采用低屈服点型钢,而边缘框架采用高强型钢。分析了面内单调荷载作用下,低屈服点型钢墙的非线性剪切屈曲性能及宽厚比的影响。对多层低屈服点钢板剪力墙进行滞回性能试验,研究刚度、强度、变形及耗能性能。结果表明:低屈服点钢板剪力墙具有优越的变形及耗能能力,侧向荷载作用下,其层间位移角能超过5%。     

Cyclic behavior of low yield point steel shear walls

This paper presents the research works on the cyclic behavior of low yield point (LYP) steel shear wall. In the LYP steel shear wall system, the LYP steel plate is used for steel panel and conventional structural steel is used for boundary frame. A series of experimental studies were carried out to examine the stiffness, strength, deformation capacity, and energy dissipation capacity of the LYP steel shear wall under cyclic load. The effect of width-to-thickness ratio of steel plate, continuity of shear wall, and the design of beam-to-column connections on the boundary frame was examined. Good energy dissipation capacities were obtained for all specimens studied. Excellent deformation capacities were obtained from both rigid frame–shear wall system and simple frame–shear wall system. The LYP steel shear wall is able to maintain stable up to 3–6% of story drift angle. A two-force strip model was also proposed to simulate the elastic and inelastic behavior of shear wall system. Good correlations were found between experimental and analytical studies. Based on these research findings, suggestions are made for the design of LYP steel shear wall systems.     

低屈服点钢板剪力墙抗震性能研究

在低屈服点钢板剪力墙体系中,内嵌钢板使用低屈服点钢,周边框架使用普通钢材。采用数值方法研究低屈服点钢板剪力墙在单调荷载作用下的抗剪性能和在反复周期荷载作用下的滞回性能。对内嵌钢板的屈服强度和高厚比进行参数分析,用于研究其对结构抗震性能的影响;分析显示低屈服点钢板剪力墙有很好的变形能力和耗能性能且能减小对主框架的影响。     

薄壁复合箱型梁的弯曲—扭转屈曲分析

对一轴心受压薄壁复合构件的屈曲进行研究。提出一个广义的分析模型，可用于分析轴心受压薄壁复合箱型梁的弯曲、扭转以及弯扭屈曲作用。此模型基于经典层压理论，考虑了任意层压堆积规律，结构的弯曲和扭转模式的耦合问题，如非对称以及对称和各种边界条件。采用一个基于位移的一维有限元模型来预测薄壁复合钢筋的临界荷载和随后的屈曲模式。从总势能的平稳值原则中推导出屈曲控制方程。轴心受压薄壁复合件的数值计算结果可用于估测纤维角、各向异性和边界条件对临界屈曲荷载和复合件模态的影响。     

Experimental Study on Low Cyclic Loading Tests of Steel Plate Shear Walls with Multilayer Slits

A new type of earthquake-resisting element that consists of a steel plate shear wall with slits is introduced. The infill steel plate is divided into a series of vertical flexural links with vertical links. The steel plate shear walls absorb energy by means of in-plane bending deformation of the flexural links and the energy dissipation capacity of the plastic hinges formed at both ends of the flexural links when under lateral loads. In this paper, finite element analysis and experimental studies at low cyclic loadings were conducted on specimens with steel plate shear walls with multilayer slits. The effects caused by varied slit pattern in terms of slit design parameters on lateral stiffness, ultimate bearing capacity and hysteretic behavior of the shear walls were analyzed. Results showed that the failure mode of steel plate shear walls with a single-layer slit was more likely to be out-of-plane buckling of the flexural links. As a result, the lateral stiffness and the ultimate bearing capacity were relatively lower when the precondition of the total height of the vertical slits remained the same. Differently, the failure mode of steel plate shear walls with multilayer slits was prone to global buckling of the infill steel plates; more obvious tensile fields provided evidence to the fact of higher lateral stiffness and excellent ultimate bearing capacity. It was also concluded that multilayer specimens exhibited better energy dissipation capacity compared with single-layer plate shear walls.     

全加劲两侧开缝钢板剪力墙弹性屈曲研究

采用有限元方法对全加劲两侧开缝钢板剪力墙在面内水平荷载作用下的弹性屈曲临界荷载、屈曲模态进行了研究。对影响其弹性屈曲性能的参数进行了分析,包括两侧和中部加劲肋与墙板的刚度比、两侧和中部加劲肋宽厚比以及墙板高厚比和边长比。给出了全加劲两侧开缝钢板剪力墙加劲肋的弹性屈曲设计参考公式,为开缝钢板剪力墙的应用提供依据。     

钢板剪力墙低周反复荷载试验研究

本文进行了6个13比例钢板剪力墙的低周反复荷载试验,重点研究了钢板墙极限承载力和滞回性能,为钢板墙结构利用屈曲后强度及抗震设计提供试验依据;本试验揭示了边柱局部屈曲、加劲肋布置形式、加劲板刚度和板高厚比对钢板墙滞回性能的影响。试验结果表明,边柱不出现局部屈曲是钢板墙发挥极限承载力的重要保证;厚板和较强的加劲肋对提高钢板墙滞回曲线的饱满度和滞回环面积是有利的;三种钢板墙以交叉加劲板的承载力和滞回性能最佳,十字加劲板次之,钢板墙结构耗能能力依赖于钢板与边柱的弹塑性变形和钢板面外鼓曲变形。试验曲线与应用弹塑性大挠度有限元法计算的滞回曲线吻合良好;利用屈曲后强度的钢板墙受剪承载力,其试验值与本课题建议公式及有限元值计算结果基本一致。     

纤维增强混凝土剪力墙抗震性能试验研究与理论分析

为根本改善混凝土基体的脆性,提高混凝土剪力墙的抗震性能和损伤容限,设计制作6个局部纤维增强混凝土（FRC）剪力墙试件,在试件变形关键部位采用FRC替代普通混凝土,并考虑高轴压比下剪力墙受压钢筋屈曲和受拉纵筋应力集中的问题,在塑性铰区纵向钢筋上设置钢套管,以改善受力钢筋的稳定性和变形性能。通过对悬臂剪力墙试件的拟静力试验,研究此类剪力墙的破坏现象、受力机理和滞回特性,探讨轴压比、FRC区高度、纵筋强度和钢套管长度等因素对墙体变形能力及耗能能力的影响。研究表明,与普通混凝土剪力墙试件相比,塑性铰区采用FRC的剪力墙试件具有较高的损伤容限和变形能力;提高钢筋强度和延性以及在纵筋上设置钢套管,对其抗震性能和耗能能力均具有明显的改善作用。     

不同屈曲约束形式的钢板剪力墙往复剪切性能试验

为研究不同冷弯薄壁型钢屈曲约束形式的钢板剪力墙的往复剪切性能,剥离框架对钢板剪力墙结构抗侧力的贡献,单独对3个不同屈曲约束形式的钢板剪力墙结构试件和1个纯钢板剪力墙结构试件进行了拟静力试验研究,并通过试验与理论分析揭示了不同屈曲约束形式的钢板剪力墙在往复剪切作用下的力学性能与失效机理。结果表明:冷弯薄壁型钢对钢板剪力墙的面外变形具有较好的约束作用,显著提高了钢板剪力墙的耗能能力、延性和承载力; 竖向屈曲约束构造形式对钢板剪力墙的耗能能力提高效果最好,其次是水平约束形式,最差是45°斜向约束形式; 对于带45°斜向约束的试件而言,由于约束形式非轴向对称,其承载力在推、拉方向上表现出明显的差异,即在拉力带垂直于冷弯薄壁型钢约束时,其承载力更高。     

Analysis on shear capacity and energy dissipation of corrugated steel plate shear wall with openings

为明确波形钢板剪力墙不发生屈曲的界限条件并分析开洞对其承载力及耗能能力的影响，基于波形钢板剪切屈曲理论推导其屈曲应力计算式，并采用数值分析及变形等级划分方法得到约束刚度比取值范围，由此提出波形钢板剪力墙不发生屈曲的界限条件为屈曲应力大于剪切屈服应力且约束刚度比大于3。通过对比开洞模型的变形等级计算参数，验证界限条件对开洞波形钢板墙的适用性，建立有限元模型研究钢板墙高宽比、钢板厚度、开洞率、洞口高宽比及洞口位置对波形钢板墙承载力及耗能能力的影响。结果表明：钢板高宽比越小、板厚越大，开洞对其承载力及耗能能力的削弱程度越大，洞口高宽比在0.33~0.5之间时开洞波形钢板墙的承载力及耗能最大，中心开洞时的最小。基于波形钢板剪力墙全截面剪切屈服的受力机理对其受剪承载力和塑性耗能计算式进行推导，并通过拟合得到考虑洞口参数影响的开洞波形钢板剪力墙受剪承载力及耗能折减系数计算式；通过9组不开洞模型和30组不同洞口尺寸及位置的开洞模型对计算式的有效性进行验证。结果表明计算值与模拟值的误差均在15%以内，适用于满足无屈曲界限条件的开洞波形钢板剪力墙。     

开洞波形钢板剪力墙受剪承载力及耗能能力分析

为明确波形钢板剪力墙不发生屈曲的界限条件并分析开洞对其承载力及耗能能力的影响,基于波形钢板剪切屈曲理论推导其屈曲应力计算式,并采用数值分析及变形等级划分方法得到约束刚度比取值范围,由此提出波形钢板剪力墙不发生屈曲的界限条件为屈曲应力大于剪切屈服应力且约束刚度比大于3。通过对比开洞模型的变形等级计算参数,验证界限条件对开洞波形钢板墙的适用性,建立有限元模型研究钢板墙高宽比、钢板厚度、开洞率、洞口高宽比及洞口位置对波形钢板墙承载力及耗能能力的影响。结果表明：钢板高宽比越小、板厚越大,开洞对其承载力及耗能能力的削弱程度越大,洞口高宽比在0.33～0.5之间时开洞波形钢板墙的承载力及耗能最大,中心开洞时的最小。基于波形钢板剪力墙全截面剪切屈服的受力机理对其受剪承载力和塑性耗能计算式进行推导,并通过拟合得到考虑洞口参数影响的开洞波形钢板剪力墙受剪承载力及耗能折减系数计算式;通过9组不开洞模型和30组不同洞口尺寸及位置的开洞模型对计算式的有效性进行验证。结果表明计算值与模拟值的误差均在15%以内,适用于满足无屈曲界限条件的开洞波形钢板剪力墙。     

半刚性连接钢框架-钢板剪力墙结构抗震性能试验研究

通过对半刚性连接框架-钢板剪力墙结构在水平反复荷载作用下的试验研究,得到了结构的滞回曲线、延性指标、水平刚度、梁柱应变、转角及各关键部位的变形。从耗能能力、刚度退化、承载力、延性等方面分析该种结构的抗震性能和耗能机理;依据应力分布、梁柱转角研究半刚性节点与钢板剪力墙的相互影响效果;分析结构的内力转换和破坏模式。结果表明：该结构具有良好的延性和耗能性能;半刚性节点在反复荷载作用下没有明显变形,节点刚度退化小,框架和钢板剪力墙协同工作良好;梁柱半刚性连接弱化了结构的整体刚度,框架自身承担的水平荷载有限;破坏模式为内填钢板剪力墙局部撕裂,拉力带作用明显,钢框架柱脚及梁柱半刚性连接部位形成塑性铰,框架整体呈弯曲破坏模式。图12表4参10     

水平加劲钢板剪力墙承载性能试验研究

加劲钢板剪力墙结构是一种适合工业化生产的新型抗侧力构件。为考察水平加劲钢板剪力墙的受力性能,分别对两榀1/3水平加劲模型试件进行推覆和低周反复荷载试验,研究水平加劲钢板剪力墙的变形性能,分析结构滞回性能、刚度退化、延性和耗能能力等。研究结果表明:水平加劲钢板剪力墙的抗侧刚度较高、耗能能力好、延性系数大于3、承载力退化缓慢。钢板剪力墙水平加劲肋门槛刚度的确定应基于钢板剪力墙弹塑性分析。     

格栅管式双钢板混凝土组合剪力墙抗震性能试验

制作了3榀格栅管式双钢板混凝土组合剪力墙试验试件,并开展组合剪力墙的低周反复水平荷载试验,绘制出了试件的滞回曲线及骨架曲线。结果表明:格栅管式双钢板混凝土组合剪力墙具有承载能力高、延性好和耗能能力强等优点;新型组合剪力墙可充分发挥格栅式钢墙板和管内混凝土的材料性能,管内混凝土处于三向受压状态,提高了混凝土的抗压强度和延性,外侧钢墙板承担全部拉应力,管内混凝土承担全部压应力,协同工作优势互补;在1/25 rad位移角状态下循环加载80次,新型组合剪力墙塑性铰区域的管内混凝土没有明显的损坏,试验全过程没有任何异响,说明新型组合剪力墙在罕遇地震时也具有良好的工作性能和抗震延性;格栅管式双钢板混凝土组合剪力墙可实现高轴压比、高延性和薄墙厚的抗震剪力墙设计要求。     

Behavior of steel plate shear wall connected to frame beams only

This paper presents the study of steel plate shear walls which are connected to frame beams only. As the shear walls are not connected to frame columns, the premature failure overall buckling or local buckling of frame columns can be prevented. In fact, most of both structural design engineers and architects prefer this kind of steel plate shear walls because the dimension of their opening space is relatively flexible by using several steel plates with small span-to-height ratio placed parallel to each other. In this paper, two steel plate shear walls were fabricated and tested. The influence of stiffeners on the hysteretic behavior of this kind of member was studied. The experimental results showed that this kind of specimen had good ductility and energy dissipation capacity. The energy dissipation capacity of specimen with stiffeners was larger than that of the specimens without stiffeners. Meanwhile, the finite element method was applied to analyze the behavior of steel plate shear walls, whose results were validated by comparing with the corresponding experimental results. Analytical results showed that the free edges deformed with evident out-of-plane deformation and should be constrained by stiffeners to meet the design requirements. The energy dissipation capacity is much better for steel plate shear walls with lower height-to-thickness ratio and larger span-to-height ratio. At last, the skeleton curve of steel plate shear wall was proposed for calculating the elastic rigidity and load-carrying capacity.     

不同面外约束下带缝钢板剪力墙的抗剪性能研究

采用有限元软件ABAQUS,考虑几何非线性和面外初始缺陷的影响,对比分析钢筋混凝土板约束、刚性板约束以及无面外约束的带缝钢板剪力墙在水平荷载作用下的刚度、抗剪承载力、延性和耗能能力,并研究面外约束对带缝钢板的应力分布和面外屈曲的影响。结果表明:钢筋混凝土板可以抑制带缝钢板的弹性屈曲,降低带缝钢板的拉力带效应,提高带缝钢板剪力墙的延性、抗剪承载力和耗能能力。为了使钢筋混凝土板能更好地约束带缝钢板的面外屈曲,建议在剪力墙的小变形阶段,混凝土板不参与抗剪。     

低屈服点钢扣板连接的试验研究

同心支撑框架被广泛用于钢结构房屋的抗震设计中。在地震激励下,同心支撑框架的支撑会承受循环拉压荷载。由于支撑的屈曲,其抗压强度通常低于抗拉强度,这可能会降低支撑框架的抗震性能。该文对采用弱扣板强支撑的设计理念进行了验证。扣板选用低屈服点钢(LYP),从而使设计的扣板在支撑屈曲前发生屈服。低屈服点钢的屈服强度很低,但其延性很好。通过一系列试验验证循环荷载作用下低屈服点钢扣板的性能。研究发现,在低屈服点钢扣板上增加槽型约束(STR)可以大大提高其抗震性能。在拉压荷载作用下,有槽型约束的低屈服点钢扣板可以提供类似大小的强度。扣板的耗能能力同样得到提高。基于此研究成果,给出低屈服点钢扣板的一些设计建议。     

钢板剪力墙的试验研究

天津津塔是我国首座采用钢板剪力墙的超高层建筑,也是目前已知规模最大的钢板剪力墙结构,其主要抗侧力体系为钢板剪力墙和钢管混凝土柱所构成的核心筒。为研究这种结构体系及其构造做法的实际受力性能,并为设计计算提供试验依据,完成了2个2跨5层1∶5缩尺比例的钢板剪力墙模型的低周往复加载试验。试件变化的主要参数包括钢板剪力墙与周边框架的连接方式以及钢板剪力墙的加劲构造措施。试验表明,钢板剪力墙结构具有较高的承载能力,稳定的滞回性能。未设置加劲肋的钢板剪力墙试件,在加载初期即发生平面外屈曲,其滞回曲线呈现一定的S形捏拢趋势;设置有4道竖向加劲肋的钢板剪力墙试件,在加载过程中未发生平面外屈曲,其滞回曲线呈饱满的纺锤形。此外,采用摩擦型高强螺栓连接的钢板剪力墙试件在加载过程中有较大噪声,可能影响结构的正常使用。     

Hysteretic behaviors of cold-formed steel beam-columns with hollow rectangular section: Experimental and numerical simulations

This paper presents a comprehensive experimental and numerical investigation on the cyclic response of cold-formed steel columns with hollow rectangular sections. The present study examined the columns׳ post-buckling strength and rigidity degradation, deformation and failure modes, ductility, and energy dissipation capacity. The cold-formed steel members exhibited stable hysteretic performance up to the point of local buckling with considerable degradation in strength and ductility. The energy dissipation mechanisms from the in-plane plastic behavior and out-of-plane elastic buckling deformation were identified. The influence of the height-to-width ratio and axial-compression ratio on energy-dissipation and failure mode was also investigated.     

钢板剪力墙抗震性能试验研究

以天津国际金融会议酒店工程为背景对钢板剪力墙的抗震性能进行试验研究。完成了3个4层1∶5缩尺比例的钢板剪力墙试件的拟静力试验。试件主要变化参数包括墙板开洞和中柱设置。试件SPSW-1墙板开洞,试件SPSW-2墙板不开洞,试件SPSW-3带有中柱,且中柱一侧墙板开洞。在钢板剪力墙的墙板上布置了槽形和一字形两种截面形式的加劲肋。试验结果表明：钢板剪力墙结构具有良好的承载力、延性和耗能能力;开洞降低了钢板剪力墙结构的刚度和承载力;中柱提高了钢板剪力墙结构的刚度和承载力;加劲肋可增强钢板剪力墙结构的刚度和稳定承载力,开洞补强效应显著。