【作者】 刘杨；

【导师】 沈蒲生；

【作者基本信息】 湖南大学 ， 结构工程， 2007， 博士

【摘要】 框支剪力墙结构起源于20世纪30年代。它是一种“上刚下柔”、竖向刚度突变的复杂高层建筑结构。多次震害分析表明,框支剪力墙结构属于抗震性能较差的高层建筑结构。但由于具有其它结构不可替代的使用功能,使其在世界各地特别是我国获得了非常广泛的应用。随着研究深入,有关框支剪力墙结构的受力特性和改进抗震性能措施先后被提出。然而仍有一些问题没有得到很好的解决。因此,对其展开深入研究是非常有实际意义的。论文完成的主要工作如下:(1)采用依次放松约束节点的子结构法,根据转换层附近竖向构件传力机制的不同,提出了框支剪力墙结构和带转换层筒体结构在静力水平荷载作用下简化计算模型,并对转换层设置高度、标准剪力墙类型、落地剪力墙刚度等因素对结构内力和侧移的影响进行了分析。(2)将框支剪力墙结构等效为悬臂杆,以悬臂杆刚度来反映框支剪力墙结构竖向刚度突变,运用结构力学中的柔度矩阵法,建立了自振特性简化计算模型,它具有计算量小适用范围广等优点,同时还可灵活的结合工程实际,提供不同精度的运算。(3)将框支剪力墙结构以转换层为界,划分为转换层上部剪力墙子结构和转换层下部框-剪子结构,借鉴框-剪结构楼层扭转新刚度模型,进行了框支剪力墙结构扭转近似计算。该方法运算简单、精度较高。(4)借鉴转换层上、下等效侧向刚度比的概念,推导出了转换层上、下等效扭转刚度比和等效层间侧移角比的计算公式与取值范围。这两个参数能更有效的控制结构扭转角、层间位移角、剪力突变以及转换层附近剪力墙的应力集中。(5)通过控制最大层间相对位移与层高之比、竖向构件轴压比等因素,推导了落地剪力墙合理刚度计算公式;根据转换层上、下等效侧向刚度比和等效层间侧移角比的取值范围,得到了落地剪力墙合理刚度取值范围。(6)提出了落地剪力墙刚度合理性综合评判模型,较为全面合理地分析了多种因素对落地剪力墙刚度合理性的影响。通过该模型对已有落地剪力墙进行评定,衡量其合理性,进而反馈给设计者相应的调整信息,可避免诸如扭转、剪重比等因素无法直接凭计算来考虑的缺点。(7)将框支剪力墙结构以转换层为界,划分为转换层上部剪力墙子结构(含转换层)和转换层下部框-剪子结构;视楼板(包括转换层楼板)为水平放置的深梁,然后采用超单元法,充分考虑剪力墙类型与布置、转换层类型的影响,对每个子结构建立考虑楼板刚度的单元刚度矩阵;最后推导了考虑阻尼影响依次放松约束节点的动力子结构法计算公式,完成了结构动力分析。(8)通过对试验数据及抗扭刚度计算公式的参数分析,探讨了轴压比、偏心距、纵横钢筋配筋强度比、剪扭比及弯扭比等诸多因素对构件抗扭刚度退化的影响。并在已有试验的基础上,给出了便于查用的构件抗扭刚度-扭转角退化曲线,它可为考虑扭转的高层建筑结构弹塑性简化分析提供条件。更多还原

【Abstract】 The shear wall structures supported on frames originated in the 1930s. It is a complex tall building structure for its asymmetric vertical rigidity. It is shown that its earthquake-resistance capability is inferior from many earthquake damage researches, but it is still widely applied in many countries, especially in China, since its superior architectural function. The mechanical properties and modified measures of the shear wall structures supported on frames are put forward successively as the research going on. Today there are still a lot of problems to be solved, and it is necessary to make an investigation on this structure. This doctoral thesis is arranged as followings:(1) According to the different force transfer mechanism near the transfer story, the analytical modeles of the shear wall structures supported on frames and the tube structures with transfer story under the dead horizontal actions are put forward by the substructure method. Some factores of influencing on the structural distortion and force action are discussed also, such as the height of the transfer story, the shear wall types, and the rigidity of the shear wall linked with ground.(2) The shear wall structure supported on frames is predigested as an equivalent cantilever bar. The asymmetric vertical rigidity of the whole structure is displayed by the rigidity of the equivalent cantilever bar. By the flexibility matrix method, a simplified model is set up for the structure free vibration calculation. It is accurate and convenient enough for use.(3) The whole structure is divided into shear wall structure above transfer story and frame-shear wall structure under transfer story two substructures. A new formula for calculating story rigidity is introduced, which can consider the frames and shear walls anti-lateral rigidity at the same time. A calculation method of torsion effect in shear wall structures supported on frames is set up. It is shown that the concept of the developed rigidity model is clear and the results are exact, which can be very useful for reference during calculating the appreciative torsion effect.(4) Using the concept of ratio of equivalent lateral rigidity, the formulas and value ranges are deduced for two new parameters, which are the ratio of equivalent torsional rigidity of the stories above the transform to the below, and the ratio of equivalent story-drift of the stories above the transform to the below. The two parameters can control the mutations of the structural torsional angle, the ratio of story-drift and the shear force effectively.(5) Some formulae of the optimal rigidity of the shear wall linked with ground are deduced strictly from the controls of resistance to shear force and the maximum ratio of the bottom floor sideway to the height. The value ranges of the optimal rigidity of the shear wall linked with ground is given by the maximum ratio of sideway to height of the bottom floor under earthquake actions, the ratio of equivalent lateral rigidity and the ratio of equivalent story-drift of the stories above the transform to the below.(6) The model of fuzzy comprehensive evaluative on the optimal rigidity of shear wall linked with the ground is presented. It can take various influencing factors into account roundly, such as torsion and the ratio of shear to weight, which can not be considered directly by other ways. So the model is more reasonable for judging the optimal rigidity of the shear wall linked with ground.(7) The whole structure is divided into shear wall structure above transfer story and frame-shear wall structure under the transfer story two substructures, and the floors are regarded as horizontal deep beams. Fully considering the types of transfer story and shear wall, the element rigidity matrix of each substructure can be set up by using super finite element method. Finally, the structural dynamic analysis with damp is carried out by dynamic substructure method.(8) According to the experimental results and the parameter analyze of the formula for torsion rigidity, the various the factors of influencing on torsion rigidity are discussed, such as the ratio of axial compressive force to axial compressive ultimate capacity of section, the eccentricity, the ratio of shear to torsion, and the ratio of moment to torsion. The degradation graph of torsion rigidity is given by the known experiments, which can be used for inelastic torsional analysis of the tall building structures.更多还原