地震作用下相邻结构的碰撞反应及控制

发布时间：2018-03-08 19:52

本文选题：相邻结构　切入点：碰撞响应　出处：《华中科技大学》2013年博士论文　论文类型：学位论文

【摘要】：现代城市中，由于人口密集且土地有限，建筑物建造的越来越密集，，这就导致相邻建筑结构之间的间距过小。或者由于建筑造型或者使用功能的要求，许多高层建筑都设计成由多个子结构组成的主-从结构。在地震作用下，相邻建筑结构之间可能会发生碰撞。对相邻结构碰撞响应以及防碰撞措施的研究，在土木工程结构的地震防护中有十分重要的现实意义。本文综合理论分析、数值模拟等手段，开展了以下几方面的研究工作： (1)基于Hertz理论推导出了新的Hertzdamp碰撞分析模型，对该模型中的阻尼常数的表达式进行了修正,通过数值验证得出该模型能够更加精确的模拟碰撞反应。然后对近断层地震作用下隔震建筑与相邻结构相碰撞的动态响应特性进行了研究，对比分析了隔震建筑与限位装置、与相邻非隔震结构以及与相邻隔震结构相碰撞时的响应特性。结果表明碰撞时基础隔震仍然能减轻上部结构的地震响应，在碰撞时加速度的敏感性大于层间位移的敏感性，并通过对比分析得出隔震建筑与两边结构相碰撞的次数要明显大于仅与一边结构相碰撞的次数。 (2)对地震作用下连接相邻结构的Kelvin型粘弹性阻尼器优化参数理论表达式的适用性作了详细的研究。共有两种减震控制目标，使主结构的平均相对振动能量最小和使两相邻结构的总平均相对振动能量最小。采用虚拟激励法，详细分析了结构模态阻尼比和场地条件的变化对粘弹性阻尼器优化参数的影响。结构模态阻尼比的变化对粘弹性阻尼器的优化参数取值影响不大，当两结构的阻尼比相同或者不同时，优化参数值都与理论值非常一致。不同场地条件下粘弹性阻尼器的优化参数值均与理论值吻合良好，更进一步的验证了基于两结构的第一阶自振频率和总质量来得到粘弹性阻尼器优化参数的正确性。 (3)采用两步法优化设计方法，对地震作用下连接两相邻结构的粘弹性阻尼器的优化布置问题进行了研究。得出当两结构间布置的粘弹性阻尼器数目越多时，粘弹性阻尼器最优布置与最不利布置时的控制效果相差越小。应避免仅布置1个粘弹性阻尼器的情况；当布置多个粘弹性阻尼器时，宜在结构的顶部和下部分布布置；当粘弹性阻尼器数量更多时，优化布置的必要性变得很小，可直接根据实际工程要求来进行布置。通过更进一步的研究表明，粘弹性阻尼器数目的优化对控制效果影响很小，重点在于对确定数目的粘弹性阻尼器的布置位置的优化。 (4)对近断层地震作用下连接相邻结构的非线性滞回阻尼器的性能进行了研究。采用Bouc-Wen模型模拟结构的滞回特性，并采用常规地震波（底波）与模拟近断层特性的等效速度脉冲进行叠加生成近断层地震波。采用参数化研究得到了非线性滞回阻尼器最优的屈服力和屈服位移，然后对非线性滞回阻尼器的控制效果进行了评价。数值分析结果表明，在加速度峰值相同的不同近断层地震波激励下，非线性滞回阻尼器的最优的屈服力和屈服位移相差不大；安装滞回阻尼器能大大减小近断层地震作用下相邻结构的振动总能量。
[Abstract]:In the modern city, due to the dense population and limited land, building more and more intensive, which leads to the spacing between adjacent structures is too small. Or due to the architectural style or the use of functional requirements, many high-rise buildings are designed is composed of a plurality of sub structure of the master-slave structure. Under the earthquake, may the collision between adjacent structures. The adjacent structure and Research on anti collision collision response measures, has very important practical significance in earthquake protection of civil engineering structures. This paper analysis theory, numerical simulation and other means, to carry out the research work of the following aspects:
(1) Hertz deduced Hertzdamp collision analysis model based on the expression of the damping constant in the model is modified by numerical verify that the model can simulate the collision reaction more accurately. Then the dynamic response characteristics of the near fault earthquake isolation building and adjacent structures of the collision are studied and the comparative analysis of the isolated buildings and limiting device, and the adjacent non isolated structure and collides with the adjacent isolation structure. The results show that the response characteristics of the collision of base isolation still can reduce the seismic response of the superstructure, the collision is greater than the acceleration sensitivity of sensitive layer displacement, and the number of isolated buildings and structures on both sides the collision is greater than the number only collides with a side structure through comparative analysis.
(2) for connecting adjacent structures under earthquake Kelvin type viscoelastic damper optimization suitability parameters of theoretical expressions were studied in detail. There are two kinds of vibration control, the main structure of the average relative vibration energy and the total average of two adjacent structures relative vibration energy minimum. Using virtual excitation method the influence of the structure, the modal damping ratio and site conditions of viscoelastic damper parameters is analyzed in detail. The structure change of modal damping ratio has little influence on the optimization parameters of viscoelastic damper, the damping ratio of the same structure as the two or not at the same time, optimal parameter values are very consistent with the theoretical value. The optimization parameters of viscoelastic the damper under different conditions were in good agreement with the theoretical value, further verified based on the first two order natural frequency of vibration and the total mass to obtain viscoelastic damping The device optimizes the correctness of the parameters.
(3) the two step optimization design method to optimize the layout problem of viscoelastic dampers connecting two adjacent structures under earthquake is studied. When the two structure layout of the viscoelastic damper number, the control effect of viscoelastic damper and the optimal layout of the most unfavorable layout should be avoided only difference is smaller. The arrangement of 1 viscoelastic dampers; when the arrangement of a plurality of viscoelastic dampers, should be at the top of the structure and lower distribution; when the number of viscoelastic dampers more, the necessity of the optimal layout is very small and can be directly arranged according to the actual requirements of the project. Through further research shows that the effect of optimization the number of the viscoelastic damper to the control effect is very small, the focus is on determining the number of optimization layout of the visco elastic damper.
(4) on the properties of the near fault earthquake back damper nonlinear hysteresis connecting adjacent structures were investigated. The Bouc-Wen model is used to simulate the hysteretic behavior of the structure, and uses the conventional seismic wave (bottom wave) and equivalent velocity pulse characteristics simulation of near fault superimposed near fault seismic waves. A parametric study using the nonlinear hysteretic damper optimal yield force and yield displacement, and to evaluate the control effect of nonlinear hysteretic dampers. The numerical results show that the near fault seismic waves at different excitation peak acceleration under the same nonlinear hysteretic damper optimal yield force and yield displacement difference; hysteretic damper installation can greatly reduce the vibration energy of adjacent structures under near fault earthquake.

【学位授予单位】：华中科技大学
【学位级别】：博士
【学位授予年份】：2013
【分类号】：TU311.3

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