【作者】 盛朝晖；

【导师】 宋波；

【作者基本信息】 北京科技大学 ， 防灾减灾工程及防护工程， 2011， 博士

【摘要】 大开口薄壁壳结构具有跨度大，自重轻，强度高，刚度较好等优点。但是由于此类结构和受力形式比较复杂，并且影响其动力特性的因素较多，尤其是地震作用下结构的动力响应存在诸多尚未解决的问题，使得对于大开口薄壁壳结构的抗震性能设计没有相应标准可循。本文对有较大矩形开口的薄壁壳结构进行了考虑流固耦合与不考虑流固耦合现象的结构有限元动力反应分析，研究了在不同的激励波加速度峰值和不同输入方向的前提下，薄壁壳结构开口位置、数量以及液面高度等对结构动力响应的影响，明确了该结构的最不利激励波输入角度。提出了对该结构进行结构计算的拟静力简化计算方法。同时对以此为背景的某电厂大型脱硫塔结构做了1：15缩小比例的振动台模型试验，并对大开口薄壁壳结构的性能设计提出了建议。取得的主要研究成果如下：（1）基于对某电厂大型脱硫塔结构原型结构进行简化后的薄壁壳结构多角度激励波加载数值模拟分析，研究了大开口薄壁壳结构的动力响应，明确了各种激励波作用下的结构加速度、结构顶部位移分布规律和结构的激励波最不利输入角度，推导出复杂薄壁壳结构的拟静力简化计算模式。（2）对某电厂大型脱硫塔结构开展了室内模拟地震的振动台模型试验，通过多角度，多激励波类型等参数的改变，明确了大开口薄壁壳结构的最不利激励波输入方向，验证了数值模拟计算的结果，为大开口薄壁壳结构的设计计算提供了大量合理并且有效的试验数据。（3）鉴于考虑结构-液体相互作用的重要性，明确了液体与结构相互作用下开口薄壁壳结构的加速度、顶部位移分布规律，以及不同液面高度等参数的变化对大开口薄壁壳结构动力反应的影响机理。通过研究大开口薄壁结构底部翘离现象，明确了由于结构内部的液体以附加质量的形式作用于薄壁壳结构，会在结构底部产生相应的附加倾覆弯矩，使得“壳振动”随着液体高度的增加而趋于严重。（4）探讨了大开口薄壁壳结构抗震性能设计模式，并综合本文的研究成果，对该类结构的性能设计问题提出了一些经济合理、简便易行的性能设计方法，以强化该类结构抗震性能多极化设计的理念。更多还原

【Abstract】 The thin-walled shell structure has its major advantages on long-span,material weight, overall structural strength and rigidity. The structure form andload condition of cylindrical shells with large-openings are complex and theinfluence factors on the stability are various. But there are many problemsunsolved of the structure dynamic response under seismic. And it has nocorresponding standard of performance-based seismic design to be follwed for thethin-walled shell structure with large-openings.This research was studying the dynamic structural responses of thethin-walled shell structures with large rectangular openings. In terms of evaluatingthe impacts on the dynamic responses regarding the number and location of theserectangular openings, two types of seismic waves (i.e., long period and shortperiod) with different acceleration peaks and input directions were applied. Theworst case scenario for the input angle of the seismic wave was also analyzed.A simplified numerical method of pseudo-static structural calculation wasderived based on the analysis on the dynamic responses of the same structures,using the finite element method for the scenarios with and without fluid-solidcoupling. The confirmation modeling was completed with a1:15physical modelof a large-scale desulfurization tower using the shaking table method. Accordingto the analysis, the major tasks and founds are as follows:(1)The numerical modeling of the targeted desulfurization tower wassimplified under the principles of1) the weights are identical and2) the dynamiccharacteristics are similar. The modeling was completed by inputtingmulti-direction seismic waves and the peak acceleration, distribution pattern ofdisplacement on structure top under these waves were generated. Throughanalyzing the modeling results, the vulnerable locations of this type of structurescan be determined and the simplified numerical calculation method was derived.The worst case scenario of wave input angle was also obtained.(2)The physical modeling was carried out with a1:15reduced scale model to the large-scale desulfurization tower using shaking table method. The modelingdata were generated with applying2types, multi-direction seismic waves withdifferent liquid surface elevations in the structure. The modeling simulationoutputs confirmed the calculation results using the numerical method, regardingthe worst wave input direction. Furthermore, the physical modeling provided anumerous of useful data for the structure calculation regarding the impacts of theconcentration rate of the liquid contained in the structure.(3)In terms of deriving the peak acceleration distribution patterns,displacements on the structure top and impact behavior on the responses (i.e., thedynamic responses of thin-walled shell structure) caused by liquid-solid couplinginteraction during earthquakes, the dynamic responses were analyzed with andwithout liquid-solid coupling using the two numerical models (the prototypedesulfurization tower and simplified thin-walled shell structure). The researchfocused more on peak acceleration alteration along with the increase of the liquidsurface and concluded that the liquid vibration scope and its energy is extremelyincreased at the liquid surface area, and causes overturning momentum. Thisfound can determine the threshold of uplift phenomenon occurring. It alsoconfirmed that the liquid contained will create extra momentum at the structurebottom because the liquid is “pushing” the structure wall to gain the requiredacceleration force and this “shell vibration” will be more severe along with theincrease of the liquid depth. Therefore, it is critical to take the “liquid-solidcoupling” into account regarding the thin-wall structures with large-span opening.(4) The method of structure performance-based seismic design was studied.This research also provided some references and recommendations for the relatedengineering coding and similar structure design in the future, based on thenumerical model and physical model analysis on thin-wall shell structure withlarge opening. These recommendations include some design standards andparameters, such as the wall thickness, input angle of the seismic waves and somemethodology of calculation simplification.更多还原