钢管混凝土异形柱-H型钢梁框架结构抗震性能研究

The special-shaped column structures comply with the architectural demand of building structures raised by modern living environment. To improve seismic behavior of the special-shaped column structure and expand its application scope in high seismic intensity regions, the seismic behavior of frame structure with special-shaped concrete-filled steel tubular columns and H-section steel beams will be experimentally and numerically studied in this project. Firstly, hysteretic experiment research and finite element research of special-shaped CFST columns under compression, bending, shear and torsion will be conducted to investigate the influences of axial compression ratio, torsion-shear ratio and loading angle on the stiffness, bearing capacity, ductility and energy dissipation. Therefore, the design method of bearing capacity correlation curves of special-shaped CFST columns under compression, bending, shear and torsion will be proposed. Secondly, an OpenSees mechanical model of special-shaped CFST column to H section steel beam joint will be proposed. The parameter values of joint shear panel, zero-length bar-slip springs and zero-length interface-shear springs of the OpenSees mechanical model will be regressed based on the hysteretic experiments of special-shaped CFST column and its frame joint. Thirdly, the frame structures with special-shaped CFST columns and H-section steel beams will be researched in hysteretic experiment. The OpenSees software will be employed to conduct finite element analysis to investigate the influences of axial compression ratio and loading angle on the plastic hinge formation. At last, the design provisions of maximum axial compression ratio, maximum drift ratio and maximum building height will be proposed and construction measures will be suggested.

异形柱结构顺应了现代居住环境对建筑结构的要求。为改善异形柱结构的抗震性能，扩大其在高烈度地区的应用范围，本项目对钢管混凝土异形柱-H型钢梁框架抗震性能进行试验和有限元研究。首先开展钢管混凝土异形柱压弯剪扭复合受力拟静力试验和有限元分析。考察轴压比、扭剪比、加载角度等因素对刚度、承载力、延性、耗能等指标的影响，提出钢管混凝土异形柱压弯剪扭承载力相关曲线设计方法。其次开展钢管混凝土异形柱-H型钢梁框架节点的OpenSees力学模型研究。基于钢管混凝土异形柱及其框架节点拟静力试验结果，确定该力学模型中节点核心区的剪切板元件、零长度粘结滑移元件和零长度剪切元件的参数取值。最后进行钢管混凝土异形柱-H型钢梁框架结构拟静力试验，考虑轴压比、加载角度等因素对塑性铰形成机制的影响，采用OpenSees软件进行有限元辅助分析，提出柱轴压比限值、层间位移角限值和房屋最大高度等规定，并提出构造措施和施工要求。

钢管混凝土异形柱结构在建筑使用功能上迎合了现代居住环境对结构构件形式的要求，提高了室内空间利用效率，具有与普通钢管混凝土结构相近的良好抗震性能，同时也符合建筑装配化和工业化的发展要求。本项目对钢管混凝土异形柱-H型钢梁框架结构（SCFSTF）的抗震性能进行了试验研究、数值模拟和理论分析。进行了4榀钢管混凝土异形柱-H型钢梁平面框架的拟静力试验，并采用ABAQUS和OpenSees软件进行框架的抗震性能分析，之后采用ETABS软件对异形柱平面框架进行Pushover推覆分析，并进行抗震性能评估。考虑钢管混凝土异形柱扭转的不利影响，对其扭转性能进行试验研究、数值模拟和理论分析，对9根钢管混凝土异形柱进行了压-扭工况下的拟静力试验研究，通过ABAQUS软件建立有限元模型研究其力学机理，并得出相应的设计方法。本项目按照项目计划任务书的要求完成，通过对钢管混凝土异形柱-H型钢梁框架结构的抗震性能分析得到了关键部位的传力机理，得到了SCFSTF结构的实际工程应用范围和适用高度以及在高烈度抗震区的抗震能力。同时提出了钢管混凝土异形柱初始抗扭刚度计算公式、抗扭承载力计算公式以及压-扭承载力相关曲线公式。本项目解决了复合受力情况下钢管混凝土异形柱在框架结构体系中的抗扭性能、钢管混凝土异形柱框架结构抗震性能分析中合理的梁柱节点力学模型、钢管混凝土异形柱框架结构体系的塑性铰形成机制等三个科学问题，完善了钢管混凝土异形柱构件、节点、体系的力学模型和设计方法，对钢管混凝土异形柱结构的工程应用提供了试验和理论依据。