基于量纲分析的地震作用下相邻建筑结构碰撞反应研究

发布时间：2018-06-02 17:28

  本文选题：地震作用 + 结构碰撞　； 参考：《哈尔滨工业大学》2015年博士论文

【摘要】：地震过程中,相邻结构间的碰撞作用是造成结构破坏、倒塌的重要原因之一。在以往的震害中已经发现很多结构碰撞现象,尤其是建筑群密集的城市区,更容易发生结构间的碰撞作用而导致结构破坏。结构间的碰撞问题研究具有重要的理论意义和工程应用价值,目前国内外学术届和工程界已经开始广泛关注该项课题的研究。过去一些学者已经对该问题进行了相关研究,由于强地震动作用下的结构碰撞反应不仅与相邻建筑结构的动力特性相关,还受到强地震动特性的影响,是涉及到诸多材料和几何变量的高非线性问题,在众多参数影响下,很难得到全面清晰的反应规律。采用量纲分析方法可以有效解决参数复杂性问题,用较少的无量纲参数来表征结构碰撞反应,可以更好的得到结构在地震作用下的碰撞反应规律,为减少城市建筑密集区的结构碰撞灾害奠定基础。目前国内外只有一位学者将量纲分析方法应用到单自由度结构碰撞反应研究,并假定碰撞过程无接触体变形发生,因此不能实时描述结构在接触过程中的力与变形,而且其研究不能用于多自由度结构碰撞反应分析。本文将量纲分析方法与接触单元方法相结合,分析了相邻单自由度碰撞体系以及多自由度碰撞体系的反应,考虑了碰撞过程中接触体之间的力、变形和能量损失,得到了碰撞过程各个时刻的结构反应,并采用谱的形式分析了各参数对碰撞反应的影响。本文的主要内容如下:(1)基于量纲分析方法,推导了单自由度摆在正弦激励作用下与障碍物发生碰撞作用的无量纲接触时间解析解、单自由度摆的无量纲位移反应和速度反应解析解,并证明了解析解的正确性和有效性,分析了结构碰撞单元参数对单摆碰撞反应的影响规律;(2)采用量纲分析方法研究了相邻多个非弹性单自由度结构的碰撞反应,比较了不同谱区条件下单边碰撞与双边碰撞对结构反应的不同作用,分析了不同的结构布局以及结构参数对碰撞反应的影响,揭示了相邻多个单自由度结构碰撞反应的自相似性;(3)进行了相邻三层和两层钢框架结构模型的碰撞振动台试验,模型相似比例1/3,模拟了结构对中碰撞和扭转碰撞两种情况,研究了结构在不同水准地震激励下的位移和加速度反应以及碰撞力发生的频次和强度;(4)基于量纲分析方法和接触单元方法,建立了非弹性多自由度体系的无量纲碰撞反应分析模型,通过与试验数据相对比,验证了该模型的正确性,分析了结构参数对碰撞反应的影响规律,揭示了多自由度体系碰撞反应的自相似性。
[Abstract]:During earthquake, the collision between adjacent structures is one of the important causes of structural damage and collapse. In the past, many structural collisions have been found, especially in urban areas with dense buildings, which are more likely to lead to structural damage. The study of collision between structures has important theoretical significance and engineering application value. At present, the academic and engineering circles at home and abroad have begun to pay close attention to the research of this subject. In the past, some scholars have studied this problem, because the structural collision response under strong ground motion is not only related to the dynamic characteristics of adjacent building structures, but also affected by strong ground motion characteristics. It is a high nonlinear problem involving many materials and geometric variables. Under the influence of many parameters, it is difficult to obtain a comprehensive and clear response law. The dimensionality analysis method can effectively solve the problem of parameter complexity, and use fewer dimensionless parameters to characterize the structural impact response, which can better obtain the collision response law of the structure under earthquake action. It lays a foundation for reducing the structural collision disaster in urban buildings. At present, only one scholar at home and abroad applies dimensional analysis method to the study of single degree of freedom structure impact response, and assumes that no contact deformation occurs during the collision process, so it is not possible to describe the force and deformation of the structure in the contact process in real time. Moreover, its research can not be used to analyze the collision response of multi-degree of freedom structures. In this paper, the dimensionality analysis method is combined with the contact element method to analyze the reaction of the adjacent single degree of freedom collision system and the multi-degree-of-freedom collision system. The force, deformation and energy loss between the contact bodies during the collision process are considered. The structural responses of each moment in the collision process are obtained, and the influence of each parameter on the collision reaction is analyzed in the form of spectrum. The main contents of this paper are as follows: (1) based on dimensional analysis method, the dimensionless contact time analytical solution of single degree of freedom pendulum colliding with obstacles under sinusoidal excitation is derived. The dimensionless displacement response and velocity response of a single degree of freedom pendulum are analytically solved, and the correctness and validity of the analytical solution are proved. The influence of structural impact element parameters on the impact response of a single pendulum is analyzed. The dimensional analysis method is used to study the impact response of adjacent inelastic single-degree-of-freedom structures. The effects of one-sided and two-sided collisions on the structural responses are compared in different spectral regions. The effects of different structural configurations and structural parameters on the collision responses are analyzed. In this paper, the self-similarity of collision responses of adjacent single-degree-of-freedom structures is revealed. The impact shaking table tests of adjacent three-layer and two-story steel frame structures are carried out. The similarity ratio of the models is 1 / 3, and two kinds of situations of structure impact and torsional impact are simulated. The displacement and acceleration responses and the frequency and strength of the collision force under different earthquake levels are studied. The dimensionality analysis method and the contact element method are used. The dimensionless collision response analysis model of inelastic multi-degree-of-freedom system is established. The validity of the model is verified by comparing with the experimental data, and the influence of structural parameters on the impact response is analyzed. The self-similarity of collision response of multi-degree-of-freedom systems is revealed.
【学位授予单位】：哈尔滨工业大学
【学位级别】：博士
【学位授予年份】：2015
【分类号】：TU317;TU311.3
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本文编号：1969588