【作者】 李晓；

【导师】 马俊；

【作者基本信息】 哈尔滨工业大学 ， 建筑与土木工程（专业学位）， 2019， 硕士

【摘要】 桥梁结构可预制化是桥梁设计未来的一个重要发展方向,将大量的现场施工步骤提前在预制工厂完成,可以提高施工作业效率、避免大量的建筑垃圾污染、有效地改善施工周围的交通拥堵、大量地减少汽车尾气的排放、极大地保障施工人员的安全、减少工程管养维护费用等。在高烈度地震区域,现有研究对节段预制式墩柱的抗震性能了解不够全面,极大地阻碍了预制墩柱在实际工程上的应用。现以“后张法装配式预应力桥墩”为研究对象,进行桥墩的拟静力特性以及动力响应方面的研究。本文基于有限元软件ABAQUS,并采用纤维梁单元模型法,对混凝土、钢筋滞回本构模型进行二次开发应用,以更好地对节段式预应力桥墩进行抗震非线性分析。通过与Ou YC所做的两组拟静力实验对比,验证纤维梁单元模型的有效性,并对其中两种典型的试件进行参数化分析,以揭示在不同初始参数条件下节段装配式桥墩抗震性能的区别,同时主要研究分析装配式墩柱延性性能的主要影响参数,本文主要研究内容主要有以下几个方面:(1)在既有文献的基础上,选择可靠的钢筋混凝土材料单周滞回性能本构模型,通过对已有试验的装配式预应力钢筋混凝土桥墩进行数值模拟,通过荷载位移曲线与拟静力实验对比分析,论证钢筋混凝土材料本构模型的可行性,以及较高的计算精度和效率。(2)利用本文选用的钢筋混凝土材料本构模型对装配式预应力钢筋混凝土桥墩进行数值模拟,避免了钢筋建模的复杂性,能合理地揭示在低周往复荷载作用下装配式墩柱结构的滞回性能、耗能能力、骨架曲线等抗震延性性能参数,并提出针对后张法装配式预应力桥墩合理抗震设计的方案。(3)基于现有规范桥梁的地震设防需求,拟合出以设计反应谱为基准的三组人工地震波,通过动力时程分析来说明不同轴压比条件下节段式预应力桥墩的区别,在桥梁的节段拼装墩抗震性能、结构抗震的适宜参数等研究成果基础上,形成了不同轴压比的节段拼装墩桥梁的抗震设计对策,展现出较大轴压比的节段式桥墩有更好的抗震性能。更多还原

【Abstract】 The prefabrication of bridge structure is an important development direction of bridge design in the future.A large number of on-site construction steps are completed in advance in prefabricated factories,which can improve the efficiency of construction work,avoid a large amount of construction waste pollution,effectively improve the traffic congestion around the construction,and a large number.Reduce vehicle exhaust emissions,greatly protect the safety of construction workers,and reduce engineering maintenance costs.In the high-intensity seismic region,the existing research has not fully understood the seismic performance of the prefabricated pier columns,which greatly hindered the application of the prefabricated piers in practical engineering.Taking the post-tensioned prestressed bridge pier as the research object,the quasi-static characteristics and dynamic response of the pier are studied.Based on the finite element software ABAQUS and the fiber beam element model method,the secondary development and application of concrete and steel hysteretic constitutive models are carried out to better analyze the seismic nonlinearity of segmental prestressed piers.The validity of the fiber beam element model is verified by comparison with two sets of quasi-static experiments made by Ou YC,and two typical test pieces are parametrically analyzed to reveal the segment assembly under different initial parameters.T he difference between the seismic performance of the piers and the main influence parameters of the ductility performance of the assembled piers are mainly studied in the following aspects:(1)Based on the existing literature,select a reliable constituti ve model of single-cycle hysteretic behavior of reinforced concrete materials,and numerically simulate the prestressed reinforced concrete bridge piers with existing tests,through load-displacement curves and quasi-static The comparative analysis of force experiments demonstrates the feasibility of the constitutive model of reinforced concrete materials,as well as the high calculation accuracy and efficiency.(2)Using the reinforced concrete constitutive model selected in this paper to numerically simulate the prestressed reinforced concrete bridge pier,avoiding the complexity of steel bar modeling,and reasonably revealing the assembled pier structure under low cycle reciprocating load The anti-seismic performance parameters such as hysteresis performance,energy dissipation capacity,and skeleton curve are proposed,and a reasonable seismic design scheme for post-tensioned prestressed bridge piers is proposed.(3)Based on the seismic fortification requirements of existing standard bridges,three sets of artificial seismic waves based on the design response spectrum are fitted,and the difference between segmental prestressed piers under different axial compression ratios is illustrated by dynamic time history analysis.Based on the research results of seismic performance of joints of bridges and suitable parameters of structural earthquake resistance,seismic design countermeasures for bridges with different axial compression ratios are formed,and segments with large axial compression ratio are displayed.The pier has better seismic performance.更多还原