压弯剪扭复合受力型钢混凝土L形柱破损机理及强度计算

发布时间：2018-01-13 23:14

  本文关键词：压弯剪扭复合受力型钢混凝土L形柱破损机理及强度计算　出处：《广西大学》2017年博士论文　论文类型：学位论文

  更多相关文章： 型钢混凝土柱 L形柱 压弯剪扭 拟静力试验 抗震性能数值模拟 破损机理 强度计算

【摘要】：2006年发布实施的《混凝土异形柱结构技术规程》(JGJ149-2006),使混凝土异形柱结构的推广应用有了国家行业标准的支持,拓展了混凝土异形柱结构的应用范围。但是由于异形柱具有承载能力较低、抗震性能不理想、钢筋较密集等缺陷,有关学者提出在异形柱截面中主要配置型钢,形成型钢混凝土异形柱。型钢混凝土异形柱具有承载能力较高、刚度较大、延性和变形性能好等优点,一定程度上可以克服普通钢筋混凝土异形柱的缺陷,扩大异形柱结构的适用范围。国内外学者在型钢混凝土异形柱正截面承载力、斜截面承载力、抗震性能等方面开展了一定的研究,并得到了一些重要研究成果,结果指出配置型钢后的钢筋混凝土L形柱在各项性能指标上有了显著提升。然而,目前关于该新型结构在压弯剪扭复合受力下的力学性能等还未见太多报道。本文在前人研究的基础上,从模型试验、有限元模拟、强度计算等几个方面对压弯剪扭复合受力型钢混凝土 L形柱的力学性能进行了系统研究。设计了一套复合受力加载装置,完成了 18个承受恒定轴压力复合弯剪扭作用的型钢混凝土 L形柱拟静力试验,试验主要考虑了扭弯比、配钢形式和肢高肢厚比三个变化参数,揭示了压弯剪扭复合受力型钢混凝土L形柱的破坏过程和破坏形态,分析了滞回特性、骨架曲线、承载能力、刚度、延性、耗能等力学性能指标以及各变化参数的影响。结果表明:小扭弯比试件主要发生弯曲破坏,大扭弯比试件发生扭转破坏,其中弯曲破坏又细分为弯曲破坏、弯剪破坏和弯扭破坏。采用ABAQUS软件对压弯剪扭复合受力型钢混凝土 L形柱试件在低周反复荷载下的抗震性能进行了仿真分析,并与试验结果进行了对比。试验与仿真相互印证的结果均表明:从抗弯角度看,实腹配钢试件的抗弯承载能力要好于空腹配钢以及空腹槽钢配钢试件的抗弯承载能力,从抗扭角度看,空腹槽钢配钢试件的承载能力要好于空腹配钢以及实腹配钢试件的承载能力。运用平衡(塑性)桁架模型并参考相关规范规程,对试件单一受力状态下的极限承载力进行了分析,探讨了轴压比和扭弯比对压弯剪扭复合受力型钢混凝土L形柱极限承载力的影响。结果表明:轴压比及扭弯比对试件的抗弯极限承载力均有较大的影响。在轴压比0.15的轴压力的作用下,试件的试验弯矩极限承载力比纯弯弯矩极限承载力都有较明显的下降,实腹配钢、空腹配钢及空腹槽钢配钢的平均降幅依次在27.4%、28.1%、28.6%左右;在小扭弯比(0～0.3)条件下,施加扭矩的作用对实腹配钢型钢混凝土试件抗弯承载力的影响最大,随着扭弯比的增大,试件弯矩承载力逐渐降低,实腹配钢、空腹配钢及空腹槽钢配钢的平均降幅依次在26%、30%、30%左右;在大扭弯比(0.89)条件下,试件弯矩承载力降低幅度很大,降幅近63.6%。
[Abstract]:In 2006, the Technical Specification for concrete special-shaped column structure was issued and implemented, which made the popularization and application of concrete special-shaped column structure supported by the national industry standard. The application scope of concrete special-shaped column structure is expanded, but due to the defects such as low bearing capacity, poor seismic performance, dense reinforcement and so on, some scholars put forward the main configuration of shaped steel in the section of special-shaped column. The special-shaped columns of SRC have the advantages of high bearing capacity, high stiffness, good ductility and good deformation performance, which can overcome the defects of ordinary RC special-shaped columns to a certain extent. Domestic and foreign scholars have carried out some research on normal section bearing capacity, oblique section bearing capacity, seismic performance and so on of SRC special-shaped columns, and obtained some important research results. The results show that the reinforced concrete L-shaped columns with profile steel have a significant improvement in various performance indexes. At present, there are not many reports on the mechanical properties of the new structure under the combined force of compression, bending, shear and torsion. Based on the previous research, this paper is based on the model test and finite element simulation. The mechanical properties of steel reinforced concrete L-shaped columns under compression, bending, shear and torsion forces are systematically studied in some aspects, such as strength calculation, and a set of composite loading device is designed. The pseudostatic tests of 18 steel reinforced concrete L-shaped columns subjected to constant axial pressure combined with bending shear and torsion have been completed. The three parameters including torsional bending ratio, steel configuration and limb height / thickness ratio have been considered in the experiment. The failure process and failure pattern of L-shaped columns of steel reinforced concrete subjected to compression, bending, shear and torsion are revealed. The hysteretic characteristics, skeleton curves, bearing capacity, stiffness and ductility are analyzed. The results show that the flexural failure occurs mainly in small torsional bending specimens, and torsional failure occurs in large torsional bending specimens, in which the bending failure is subdivided into bending failure. ABAQUS software was used to simulate the seismic behavior of steel reinforced concrete L-shaped columns subjected to compression, bending, shear and torsion under low cyclic cyclic loading. The results are compared with the experimental results. The experimental results and simulation results show that: from the point of view of bending resistance. The flexural bearing capacity of the solid web steel specimen is better than that of the hollow steel matching and the hollow channel steel fitting specimen, from the angle of torsion resistance. The load-carrying capacity of hollow channel steel fitting specimen is better than that of empty stomach steel matching and solid web steel fitting. The balanced (plastic) truss model is used and the relevant specifications are referred to. The ultimate bearing capacity of the specimen under single load is analyzed. The influence of axial compression ratio and torsional bending ratio on ultimate bearing capacity of steel reinforced concrete L-shaped columns under compression, bending, shear and torsional forces is discussed. The axial compression ratio and torsional bending ratio have great influence on the ultimate bearing capacity of the specimens under the axial pressure of 0.15. The ultimate bearing capacity of test specimens is obviously lower than that of pure bending moment, and the average decrease of steel distribution of solid web, fasting steel and channel steel is 27.4% and 28.1% respectively. About 28.6%; Under the condition of small ratio of torsion and bending, the effect of torque on the flexural capacity of steel reinforced concrete specimens with solid web is the greatest. With the increase of the ratio of torsion and bending, the bending capacity of steel reinforced concrete specimens decreases gradually. The average decrease of solid steel, empty stomach steel and empty channel steel was about 30% or so in turn. Under the condition of large torsional bending ratio of 0.89), the bending moment bearing capacity of the specimen decreases by a large extent, which is about 63.695%.
【学位授予单位】：广西大学
【学位级别】：博士
【学位授予年份】：2017
【分类号】：TU398.9
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本文编号：1420976