高轴压比钢管混凝土组合剪力墙抗震性能研究

发布时间：2018-11-06 08:52

【摘要】：钢管混凝土组合剪力墙是一种在钢筋混凝土剪力墙中布置钢管形成的组合构件，承载力高，抗震性能好，适用于高层及超高层建筑结构体系。本文通过在约束边缘构件位置和截面中部设置多根钢管，设计了一组新型钢管混凝土组合剪力墙。完成了10片高宽比为2.08的剪力墙试件在高轴压比（0.44~0.73）下的低周往复加载试验，，研究其破坏形态、承载力、变形能力、滞回性能等抗震性能。试验结果表明：试件的破坏形态为压弯作用下的受弯破坏，墙底压坏范围为整个试件宽度和300~400mm高度，钢管与混凝土之间没有出现明显的滑移；与钢筋混凝土剪力墙相比，加入钢管后，在轴向压力最大增加19%的情况下，抗弯承载力提高了23%~35%，试件的屈服位移角θ y达到1/300，峰值位移角θ p不低于1/100，极限位移角θ u达到1/75，个别试件接近1/40，变形能力提高了约30%，试件的滞回性能明显改善，证明本文设计的钢管混凝土组合剪力墙具有良好的抗震性能和抗倒塌能力。试验中在峰值荷载前试件的截面应变分布基本符合平截面假定，约束边缘构件内的钢管和纵筋箍筋均已屈服，而截面中部的钢管和箍筋始终没有屈服；推导了一种考虑钢管约束作用的剪力墙受弯承载力计算方法，与试验结果比较接近；提出了修正的轴压比计算公式；钢管混凝土与外围混凝土的轴压分配可以按照叠合柱规程的方法计算；设置螺旋箍筋约束暗柱的方法可有效改善剪力墙的抗震性能，但效果不如钢管混凝土组合剪力墙显著。使用有限元软件MSC.Marc完成了试件的有限元数值模拟，经过试验结果标定后完成了钢管混凝土组合剪力墙的参数分析。结果表明：在截面两端和中部设置多根钢管后，在高轴压比下剪力墙具有较好的承载力、刚度和变形能力，抗压与抗剪承载力明显提高，后期滞回性能更加稳定；随着轴压比的提高，承载力和刚度提高但延性和耗能能力降低，但变化幅度随着轴压比的增大而减小；提高钢管配钢率可以有效提高钢管混凝土组合剪力墙的承载力和刚度，对变形能力提高有限；提高钢管和混凝土强度等级，剪力墙的承载力和刚度有了明显的提高，而变形能力和延性没有明显的改善。在试验和有限元模拟的基础上，提出了钢管混凝土组合剪力墙的设计建议。
[Abstract]:Concrete-filled steel tubular composite shear wall (CFST) is a kind of composite member arranged in reinforced concrete shear wall with high bearing capacity and good seismic performance. It is suitable for high-rise and super-high-rise building structure system. In this paper, a new type of concrete-filled steel tube composite shear wall is designed by setting several steel tubes in the position of restrained edge member and in the middle of section. Ten shear wall specimens with a aspect ratio of 2.08 have been subjected to low-cycle reciprocating loading under high axial compression ratio (0.44 ~ 0.73). The seismic behavior such as failure mode, bearing capacity, deformation capacity, hysteretic performance and so on have been studied. The test results show that the failure mode of the specimen is bending failure under the action of compression and bending, the range of the wall bottom compression damage is the whole specimen width and 300~400mm height, and there is no obvious slip between the steel tube and concrete. Compared with reinforced concrete shear wall, when steel tube is added, the flexural bearing capacity increases by 23% and 35%, and the yield displacement angle 胃 y reaches 1 / 300, and the peak displacement angle 胃 p is not less than 1 / 100. The ultimate displacement angle 胃 u is 1 / 75, and the deformation capacity of individual specimens is close to 1 / 40. The deformation capacity of the specimen is increased by about 30%, and the hysteresis performance of the specimen is obviously improved. It is proved that the CFST composite shear wall designed in this paper has good seismic performance and collapse resistance. In the test, the strain distribution of the specimen before the peak load basically accords with the assumption of the plane section, the steel pipe and the stirrups in the restrained edge member have both yielded, but the steel pipe and stirrups in the middle of the section have never yielded. A method for calculating the flexural capacity of shear wall considering the constraint of steel pipe is derived, which is close to the experimental results, and a modified formula for calculating axial compression ratio is proposed. The axial compression distribution between concrete-filled steel tubular (CFST) and surrounding concrete can be calculated according to the rules of superimposed columns, and the seismic behavior of shear walls can be improved effectively by the method of using spiral stirrups to restrain dark columns, but the effect is not as good as that of CFST composite shear walls. The finite element numerical simulation of the specimen is completed by using the finite element software MSC.Marc, and the parameter analysis of concrete filled steel tubular composite shear wall is completed after the test results are calibrated. The results show that the shear wall has better bearing capacity, stiffness and deformation capacity under high axial compression ratio, the compressive and shear capacity is obviously improved, and the hysteretic performance is more stable in the later stage after the multi-steel pipe is installed at both ends and the middle part of the section, and the shear wall has better bearing capacity, stiffness and deformation ability under the high axial compression ratio. With the increase of axial compression ratio, the bearing capacity and stiffness increase, but the ductility and energy dissipation capacity decrease, but the range of variation decreases with the increase of axial compression ratio. Increasing steel pipe ratio can effectively improve the bearing capacity and stiffness of CFST composite shear wall, and improve the deformation capacity of CFST composite shear wall. By increasing the strength grade of steel tube and concrete, the bearing capacity and stiffness of shear wall are obviously improved, but the deformation capacity and ductility are not improved obviously. On the basis of experiment and finite element simulation, the design suggestion of CFST composite shear wall is put forward.
【学位授予单位】：清华大学
【学位级别】：硕士
【学位授予年份】：2013
【分类号】：TU398.9;TU352.11

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