塑性铰区采用纤维增强混凝土柱变形计算方法研究

发布时间：2018-08-01 08:00

【摘要】：框架结构是一种常用的建筑结构体系,其柱的变形性能决定着整个结构的变形能力。纤维增强混凝土(FRC)具有具有高强度、高延性、拉伸应变硬化和抗损伤能力强等优点,可以显著改善混凝土结构的抗震性能。为了改善钢筋混凝土柱的变形能力及抗震性能,本文将FRC应用于钢筋混凝土柱的塑性铰区,柱的其余部位仍采用普通混凝土。对FRC柱及其框架结构的抗震性能和变形进行研究,有较好的理论意义和实用价值。本文采用试验和有限元模拟相结合方法对FRC柱进行研究。首先做了9根FRC柱和1根普通混凝土柱的拟静力试验,然后采用OpenSees软件进行模拟。基于试验数据以及模拟所得的参数,根据截面力的平衡方程和截面变形的平截面假定,推导出塑性铰区采用FRC柱在不同极限状态时的曲率。根据柱的曲率分布规律,沿柱高积分得到弯曲变形所引起的柱顶水平位移；采用Sezen模型,根据已求得的曲率,推导出由柱底纵筋与混凝土粘结滑移所引起的柱顶水平位移；考虑了柱剪切变形引起的柱顶水平位移。与试验结果对比表明,开裂、屈服、峰值荷载和极限状态时的位移计算值与试验值吻合较好。对柱塑性铰区采用FRC的框架结构,利用Perform 3D和SAP 2000两种软件进行了静力弹塑性分析。对两种软件的同一算例结果进行对比,验证模型的正确性,然后分别分析柱塑性铰区采用FRC框架结构的变形能力。结果表明,柱塑性铰区采用FRC框架结构,承载能力可提高30%-40%,屈服位移和峰值荷载对应位移均有所提高,基底剪力-顶点位移曲线下降段缓慢。
[Abstract]:Frame structure is a kind of commonly used building structure system. The deformation performance of columns determines the deformation capacity of the whole structure. Fiber reinforced concrete (FRC) has the advantages of high strength, high ductility, tensile strain hardening and strong damage resistance, which can significantly improve the seismic performance of concrete structures. In order to improve the deformation capacity and seismic behavior of reinforced concrete columns, FRC is applied to the plastic hinge region of reinforced concrete columns, and the rest of the columns still use ordinary concrete. The research on seismic behavior and deformation of FRC column and its frame structure has good theoretical significance and practical value. In this paper, the FRC column is studied by means of test and finite element simulation. The pseudostatic tests of 9 FRC columns and 1 ordinary concrete column were carried out at first, and then simulated by OpenSees software. Based on the experimental data and the simulated parameters, the curvature of FRC columns in plastic hinge region under different limit states is derived according to the equilibrium equation of cross-section force and the assumption of plane section of section deformation. According to the curvature distribution law of the column, the column top horizontal displacement caused by bending deformation is obtained by integral along the column height, and the column top horizontal displacement caused by the bond slip between column bottom longitudinal reinforcement and concrete is deduced by using Sezen model and according to the curvature obtained. The column top horizontal displacement caused by column shear deformation is considered. Compared with the experimental results, the calculated values of crack, yield, peak load and limit state are in good agreement with the experimental values. The FRC frame structure is used in the plastic hinge region of the column. The static elastic-plastic analysis is carried out by using Perform 3D and SAP 2000 software. The results of the same example of the two kinds of software are compared to verify the correctness of the model, and then the deformation ability of the column plastic hinge region using FRC frame structure is analyzed respectively. The results show that the FRC frame structure is adopted in the plastic hinge region of the column, and the bearing capacity can be increased by 30% -40%. The yield displacement and the peak load corresponding displacement are both increased, and the descent section of the shear-vertex displacement curve of the base is slow.
【学位授予单位】：西安建筑科技大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TU377.9

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