钢管橡胶混凝土柱的阻尼比及其抗震性能有限元分析

发布时间：2018-10-13 19:37

【摘要】：地震过程中有效耗散地震能量的性能对保证建筑结构在遭遇地震时的安全性具有重要意义,因此如何提高建筑结构的耗能能力是我们面临的重要课题。钢管混凝土结构具有承载力高、延性好、经济效益好等优点,被广泛应用于实际工程中。徐培蓁、河野昭彦基于钢管混凝土柱屈服后承载力降低不明显及延性好的性能,提出了允许部分柱屈服的混合屈服机制。为提高屈服柱的耗能能力,并有效利用废弃橡胶,本课题提出了：钢管橡胶混凝土柱。内填橡胶混凝土由于外包钢管的约束作用,其承载力将明显提高,且属于粘弹性材料的橡胶将提高屈服柱的阻尼耗能能力。因此钢管橡胶混凝土柱在地震时能有效耗散地震能量,从而避免建筑结构在地震中的破坏。本文采用试验及理论分析方法,测得了不同橡胶掺量、轴压下钢管橡胶混凝土柱的固有频率及阻尼比,并将其应用到框架结构的弹塑性时程分析中,研究阻尼耗能对混合屈服机制框架结构抗震的影响。具体介绍如下： (1)本文设置了四根钢管橡胶混凝土柱,控制参数为橡胶掺量和轴压比,分别为橡胶掺量=0%、10%、20%、30%、轴压比n=0、0.2、0.4、0.5,利用自由振动法测得钢管橡胶混凝土柱的时域波形,采用时域分析法,分析柱的频率及阻尼比。结果表明橡胶掺量在20%时,阻尼比的增加倍率最大。施加轴压后,改变了钢管橡胶混凝土柱的悬臂状态,对结构的频率及振型影响较大,但阻尼比仍表现出随着橡胶掺量的增加而增加的规律。 (2)利用有限元分析软件SNAP,对钢管橡胶混凝土柱阻尼比测试试验进行模拟分析,得到了钢管橡胶混凝土柱的频率及振型。在悬臂状态时,其结果与试验结果具有一致性。在模拟轴压影响时,由于试验加载装置的复杂性,难以在模拟中实现与试验状态的一致,模拟值与试验值有一定差距。 (3)利用SNAP对基于混合屈服机制设计的钢管橡胶混凝土框架结构进行弹塑性时程分析,研究不同橡胶掺量对层间位移、阻尼耗能、框架柱的剪力及变形能的影响。结果表明：屈服柱阻尼比的提高对减小层间位移,增加框架结构的阻尼耗能具有显著效果,能有效提高结构的抗震安全性。
[Abstract]:The performance of effectively dissipating seismic energy during earthquake is of great significance to ensure the safety of building structure in the event of earthquake. Therefore, how to improve the energy dissipation capacity of building structure is an important subject we are facing. Concrete-filled steel tube (CFST) structure is widely used in practical engineering because of its high bearing capacity, good ductility and good economic benefit. Xu Peizhen, Kono Zhaoyan proposed a hybrid yield mechanism to allow partial column yield based on the low bearing capacity and good ductility of concrete-filled steel tubular columns after yielding. In order to improve the energy dissipation capacity of yield column and to utilize waste rubber effectively, this paper puts forward: steel tube rubber concrete column. The bearing capacity of the rubber filled concrete is obviously increased because of the restraint of the outer steel pipe, and the damping and energy dissipation capacity of the yield column will be improved by the rubber which belongs to viscoelastic material. Therefore, the rubber filled steel tubular concrete column can dissipate the seismic energy effectively during the earthquake, thus avoiding the damage of the building structure in the earthquake. In this paper, the natural frequency and damping ratio of rubber filled concrete filled steel tubular columns with different rubber content and axial compression are measured by means of experimental and theoretical analysis, and applied to the elastoplastic time history analysis of frame structures. The effect of damping energy dissipation on seismic resistance of frame structures with hybrid yield mechanism is studied. The details are as follows: (1) four concrete filled steel tube columns are set up in this paper. The control parameters are rubber content and axial compression ratio. The ratio of axial pressure to axial pressure is 0.20.40.The time domain waveforms of concrete filled steel tubular columns are measured by free vibration method, and the frequency and damping ratio of columns are analyzed by time-domain analysis method. The results show that the increase of damping ratio is the largest when the rubber content is 20. After axial compression, the cantilever state of rubber filled concrete filled steel tube column is changed, which has a great influence on the frequency and mode shape of the structure. But the damping ratio still increases with the increase of rubber content. (2) the test of damping ratio of rubber concrete filled steel tube column is simulated by finite element analysis software SNAP,. The frequencies and modes of rubber filled concrete filled steel tubular columns are obtained. In the cantilever state, the results are consistent with the experimental results. When simulating the influence of axial compression, because of the complexity of the test loading device, it is difficult to realize the consistency with the test state in the simulation. (3) Elastoplastic time history analysis of rubber filled steel tube concrete filled steel tube frame structure based on hybrid yield mechanism is carried out by using SNAP to study the effect of different rubber content on interlayer displacement and damping energy dissipation. The influence of shear force and deformation energy of frame column. The results show that the increase of yield column damping ratio has a significant effect on reducing the interstory displacement and increasing the damping energy dissipation of the frame structure, and can effectively improve the seismic safety of the structure.
【学位授予单位】：青岛理工大学
【学位级别】：硕士
【学位授予年份】：2013
【分类号】：TU398.9;TU352.11

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