【作者】 刘义；

【导师】 赵鸿铁； 薛建阳；

【作者基本信息】 西安建筑科技大学 ， 结构工程， 2009， 博士

【摘要】 异形柱结构由于具有独特的优越性,不仅受到用户和房地产开发商的青睐,同时得到了国家的大力支持。目前,在实际工程中应用的均为钢筋混凝土异形柱结构,在近20多年的研究和应用过程中,钢筋混凝土异形柱框架节点承载能力低、抗震性能差以及节点区梁柱钢筋密集导致混凝土不容易浇筑密实等不足逐渐显现出来,这直接影响到其在高层及高烈度区的应用。为了改善钢筋混凝土异形柱框架节点的不足,扩大其应用范围,同时完善型钢混凝土异形柱结构体系以及丰富型钢混凝土结构,在课题组已有研究的基础上,对型钢混凝土异形柱框架节点进行了较为系统的研究。主要研究内容及成果概括如下：(1)为了研究型钢混凝土异形柱框架节点的破坏特征和抗震性能,进行了9个中间层边节点、4个角节点和4个中节点的低周反复荷载试验,考虑了截面配钢形式、轴压比、翼缘外伸宽度以及节点核心区配钢率(配筋率)等参数的变化。试验采用柱端加载的方式,观察了各类型节点的破坏过程及破坏形态,并分析了试件的荷载—位移滞回曲线、骨架曲线、层间位移角和位移延性以及耗能能力等力学特性。结果表明：SRC异形柱框架节点的典型破坏形态是节点核心区剪切斜压破坏和梁端弯剪破坏；滞回曲线饱满,层间位移角延性系数及位移延性系数介于1.80-5.63,弹塑性极限层间位移角约为1/67-1/28,等效粘滞阻尼系数介于0.150-0.293,破坏时节点核心区的剪切角约为0.025-0.042。(2)通过分析试验得到的荷载—位移滞回曲线以及骨架曲线,提出了型钢混凝土异形柱框架节点的恢复力模型。即考虑屈服、极限以及破坏的刚度退化三线性模型,通过回归试验数据,给出了骨架曲线各阶段的刚度公式以及正反向卸载刚度退化规律,同时在分析滞回曲线的基础上给出了加卸载滞回规则。(3)为了弥补试验中无法观察到试件内部的受力情况以及其它工况下试件的受力性能,利用非线性有限元软件ABAQUS 6.8对本次试验试件进行了模拟分析,得到了试件的变形图、应力图以及荷载—位移骨架曲线,计算结果与试验结果符合较好。同时对承载力及延性影响因素如翼缘中是否配置型钢、翼缘伸出长度以及轴压比进行了补充计算。结果表明,翼缘中是否配置型钢对边节点和角节点的承载力影响不大,但对于中节点有一定影响；翼缘中配置型钢的试件的延性总体上要优于不配型钢的试件。随着翼缘伸出长度的增加,试件的承载力逐渐增加,但增长的幅度则逐渐减小,另外文中给出了翼缘伸出长度影响系数；试件的变形能力随翼缘伸出长度的增加而逐渐增强。随着轴压比的增大,试件的承载力逐渐提高,但增长幅度不大,而试件的延性逐渐变差,特别是当轴压比大于0.6后,变形能力急剧下降。(4)在试验研究的基础上,分析了节点核心区受到的剪力和扭矩。给出了型钢混凝土异形柱框架节点的抗剪机理并分析了各特征点处各抗力元件承担的剪力。通过对试验数据的回归,得到了型钢混凝土异形柱框架节点的抗裂以及抗剪承载力计算公式。对于角节点,给出了剪扭作用下的受剪和受扭承载力计算公式,并给出了空腹式和实腹式配钢的剪扭构件计算模型的简化方式。(5)结合本次试验,给出了型钢混凝土异形柱框架节点的连接构造方式,包括型钢混凝土异形柱(空腹式、实腹式)和钢筋混凝土梁、型钢混凝土梁以及钢梁的具体连接措施；针对构件在地震作用下受到的扭矩,提出了抗扭构造措施；同时在借鉴矩形截面型钢混凝土节点研究的基础上,给出了节点内力传递协调的构造措施。更多还原

【Abstract】 Due to the unique advantages of special-shaped column structure, it is not only welcome by users and real estate developers, but also supported by government. By now, in practical engineering the most applications are reinforced concrete (RC) column structure. But in the past 20 years of research and application, some shortcomings of such structure are gradually exposed, such as low bearing capacity, weak seismic performance and steel bars are too crowded to pour concrete densely well. These disadvantages directly affect their applications in high-rise and high-intensity area. In order to improve the shortcomings of RC special-shaped column-beam joints and expand its scope of application, at the same time enrich the system of steel reinforced concrete structures (SRC) and improve the SRC special-shaped column structure system, the following work was done on the basis of existing research.(1) In order to investigate the failure modes and seismic behavior of SRC special-shaped column-beam joints,17 specimens were tested under low cyclic reversed loading. The failure process and patterns were obtained. The failure characteristics, mechanical behaviors such as the loading-displacement hysteretic loops, load bearing capacity, story drift rotation, energy dissipation, displacement and rotation ductility of the joints are analyzed. It is shown that the main failures of the column-beam joints are those of shear diagonal compression in the core zone of the joint and shear-bending at the beam root. The hysteretic loops of the joints are plump. The ductility factors of the story drift and the rotation are between 1.80 and 5.63. The ultimate elastic-plastic story drift rotation is about 0.015 to 0.036 and the energy dissipative factor is about 0.150 to 0.293. The shear deformation of joint core is about 0.025 to 0.042 as the joint failed.(2) By analyzing the test loading-displacement hysteretic curves and skeleton curves, the restoring force model of SRC special-shaped column-beam joint was presented. It was three-line model of stiffness degradation considering yielding, ultimate and damage. Through the regression of test data, the stiffness formula of various stages of skeleton curves as well as the stiffness degradation laws for the unloading stiffness were given. And on the analysis of the hysteresis curve the loading and unloading hysteresis rules were given.(3) To make up for the lack of testing, such as the internal stress condition can not be observed as well as the performance of the specimen under other operating conditions, making use of non-linear finite element software ABAQUS 6.8 to simulate and analyze the test specimens, the deformation figure, stress distribution figure and the load-displacement skeleton curves were obtained. The calculation results are in good agreement with the experimental results. At the same time, some factors which affect the bearing capacity and ductility, such as the flange is configured with steel or not, the extending length of the flange, and axial compression ratio, were further analyzed. The calculation results showed that the specimens flange configured with steel or not has little influence to the corner joints and exterior joints, but has a certain influence to the interior joints, and the ductility of specimens whose flange configured steel are better than the specimens without steel. With the extended length of the flange increases the bearing capacity of the specimen is gradually increased, but the increase rate is gradually reduced, at the same time the influence factors of the flange extended length are also presented. And the deformation behavior of specimens increases gradually with the increase of extended flange length. With the axial compression ratio increases, the bearing capacity of the specimen increase with low rate, but the ductility of the specimen gradually worse, and especially when the axial compression ratio is greater than 0.6, the deformation behavior dropped sharply.(4) Based on the test results, the shear force and torque of joint core were analyzed. And shear mechanism was presented and bearing capacity of the resistance elements on characteristic points was analyzed. Through the regression of test data, the crack as well as the shear strength formulas of SRC special-shaped column-beam joint was obtained. For the corner joint, the shear and torsion bearing capacity formulas were also presented under the action of shear-torsion. And the simplified way of shape steel in lattice and solid steel member for shear-torsion member.(5) Based on the test, the connection construction measure of SRC special-shaped column-beam joints were presented, including SRC column (lattice and solid steel) with RC beam, SRC beam and S beam. The construction measure of anti-torsion and coordination for internal force were also presented.更多还原