压弯剪扭复合受力下型钢混凝土构件的性能及设计方法研究

With the increasing of high-rise buildings, large span and overloaded structures, steel reinforced concrete (SRC) structures are more and more widely applied in the middle & large cities. The SRC components forced with combined loads are commonly aroused in engineering. However, in our country, there is no designing calculation method for the torsion of SRC components in the code or specification of composite structure, and theoretical researches are lagging behind the engineering application. In order to ensure the safety of this kind of structure, a issue has been put forward to solve the torsion in SRC structures, so that the scientific and reasonable designing method must be proposed..This item puts forth the research object of SRC structure, whose forced state is bearing with pressure, bending, shear and torsion. Through the ways of test of low cyclic reversed loading, theoretical analysis and numerical simulation, revealing the failure mechanism, establishing the model of theoretical analysis and proposing the formulas of calculating the strength and stiffness can achieved for this structure. At the same time, the influence of various changing parameters in seismic resistant capacity and deformation performance will be analyzed. Based on the ductility demand, its limit value of axial compression ratio under the state of pressure, bending, shear and torsion need to be researched, and construction measures of improving the torsional properties and anti-seismic behavior should be put forward. In a word, the research results can complete the computation theory of SRC structures and guide for designing this structure, so it is rather important in the theoretical significance and the utility value of engineering to expanding the SRC structures.

随着高层、大跨和重载结构的日益增多，型钢混凝土结构的应用越来越广泛。工程应用中，复合受扭型钢混凝土构件也经常出现，但是，目前我国组合结构技术规程中缺乏关于型钢混凝土构件的抗扭设计方法，理论研究也相对滞后于工程应用，复合受扭的研究很少。因此，亟需对其相关问题进行深入和系统的研究，提出科学合理的设计方法，以确保该类结构的安全。.项目以压弯剪扭复合受力下型钢混凝土构件为研究对象，分别研究单调扭矩和反复扭矩时该类构件的受力性能，通过系列试验研究，揭示其内力分布规律、变形特点、破坏机制以及滞回特性，获取建立理论分析模型所必须参数；编写计算机程序，分析各变化参数对复合受扭型钢混凝土构件受力性能的影响，通过理论研究提出压弯剪扭复合受力下型钢混凝土构件的强度计算公式，提出能有效提高其抗扭性能的合理构造措施。研究结果对完善型钢混凝土结构计算理论和指导型钢混凝土结构的设计，都具有重要的理论意义和工程应用价值。

首先研究研发了一套能实现压弯剪扭加载的试验装置，设计了92 个试件的系列加载试验，揭示了压弯剪扭复合受力型钢混凝土构件的内力传递途径、破坏机理，观察受力全过程 及损伤演化规律，测试滞回特性并建立复合受扭状态下的抗震恢复力模型，得到了理论分析所必需的参数。编写高精度非线性有限元数值分析程序，对不同参数复合受扭各种型钢混凝土构件进行数值分析，计算其抗震承载能力和变形性能。根据试验揭示的破坏机理，建立理论分析模型，推导复杂应力状态下型钢混凝土构件的极限承载力计算公式，并提出实用设计方法和构造措施。