【作者】 魏敏；

【导师】 周方圆；

【作者基本信息】 华中科技大学 ， 结构工程， 2017， 硕士

【摘要】 许多实例表明,相邻结构在强震发生时,往往因各自不同的动力特性而产生较大的响应差异,结构间发生碰撞的可能性很大。相邻结构的碰撞会导致严重的建筑破坏、结构破损甚至整体倒塌,危及人身财产安全,造成巨大的经济风险。近年来,基于性能的抗震设计日益得到重视,这就需要更为先进、精确和高效的基于可靠度的评估方法来减小地震碰撞风险,而在这其中,最直接有效的方法便是设置合适的相邻间距。鉴于此,我国作为地震多发国家之一,进行相邻结构临界间距的性能评估具有重要的理论研究意义和工程应用价值。本文将基于性能的抗震设计理论应用于相邻结构的临界间距评估中,通过随机振动理论推导出相邻结构的地震易损性,然后将相邻结构临界间距的计算表述为逆可靠性问题,通过误差控制迭代程序,求出某一具体的碰撞概率所对应的临界间距值,最后开展了两个多层钢框架结构模型碰撞的振动台试验,以此验证上述理论的正确性和有效性。主要研究成果如下:(1)基于随机振动理论,分别推导了线弹性体系随机响应的非几何谱特征、时变带宽参数和失效概率,进而计算单个结构的地震易损性。(2)基于可靠性理论,考虑一致的场地危险性水平,分别求出相邻结构在碰撞位置处的相对位移超越固定的临界间距值时的年平均超越频率和50年超越概率,进而求出某一具体的碰撞概率所对应的临界间距值。(3)进行了两个多层钢框架结构模型碰撞的振动台试验,模型分别设计为三层和两层钢框架,缩尺比例为1:3,质量块对称布置,得到结构在不同的地震峰值加速度和相邻间距下碰撞楼层的相对位移响应,验证了上述理论的正确性和有效性。更多还原

【Abstract】 When the strong earthquake happens,there are many cases showing that a high probability of collision between adjacent structures exists because of the response differences caused by their various dynamic characteristics.Poundings always generate structural or architectural damages,even collapse of the whole buildings,endangering the safety of human life and property and bringing great economic risks.In recent years,much emphasis is given to the performance-based seismic design which makes it necessary to reduce the pounding risks through a more advanced,accurate and efficient assessment method based on reliability theory.In view of this,it has great theoretical significance and engineering application value to do performance evaluation on the critical distance between adjacent buildings in China which is one of the most earthquake-prone countries.In this study,the performance-based seismic design theory is applied to seismic performance evaluation of adjacent structures.With the reliability theory,the seismic pounding fragility of adjacent structures is proposed,and the calculation of critical distance is expressed as an inverse reliability problem,then the value corresponding to a specific pounding probability can be derived by an error-actuated iterative procedure.Finally,the shaking table tests are conducted to investigate the pounding responses of two multiple-storey steel framed model structures and to verify the correctness and validity of the theory mentioned above.The main results of this study are as follows:(1)By means of the random vibration theory,the non-geometric spectral characteristics,time-variant bandwidth parameter and failure probability of random response processes of linear elastic systems are derived,then the seismic fragility of single building is calculated.(2)With the reliability theory and considering a continuum of site hazard levels,the mean annual frequency and exceeding probability over 50 years of the relative displacement at potential pounding location of adjacent buildings exceeding a fixedcritical distance are obtained,and then the critical distance corresponding to a specific pounding probability can be calculated.(3)A series of shaking table tests of two multiple-storey steel framed model structures are conducted,one two-storey and another three-storey steel frame models whose added mass is placed symmetrically are designed with a 1/3 scale.The relative displacement responses of pounding storey of the frames under various earthquake intensities and critical distances are measured to verify the correctness and validity of the theory mentioned above.更多还原