【作者】 朱彤；

【导师】 林皋； 周晶；

【作者基本信息】 大连理工大学 ， 防灾减灾工程， 2004， 博士

【摘要】 模型试验是研究结构在不同荷载作用下的反应以及从中发现结构内力和变形的内在规律的一门古老的技术。在计算机技术飞速发展的今天，模型实验方法仍然在结构工程技术发展和进步方面起到不可替代的作用。模型试验可以验证设计计算方法的有效性和正确性，又可直观地给出复杂细节的受力状态。特别对于未能建立理想数学模型的问题的研究，更是不可缺少的研究方法。 相似理论是模型试验方法的基础和前提，通过模型试验的实践与体会，作者研究了结构动力模型试验与动力模型破坏试验中保持模型与原型相似的三种基本要求与相似处理技巧。同时指出，对结构动力特性，弹性振动响应与破坏形态等不同的试验目的，相似要求也有所差别。掌握这一技术可以通过模型试验加深对结构动力特性和破坏形态的认识，获得更多有用的信息。其中，特别对复杂的土工建筑物动力模型破坏试验的相似问题，提出了一些新的概念。 大型混凝土结构模型试验材料的选择对于试验结果有重要意义。本文作者对低强度仿真混凝土材料的材料配比、力学性能以及实际应用进行了分析研究，分析结果表明，仿真材料对于大体积结构的物模试验是比较理想的材料；可以在短期内重复进行多组模型试验，从而可以消除模型试验中的偶然性和不确定因素的影响，提高模型试验的可靠度。 在目前所应用的抗震动力理论范围内，水中结构的计算方法通常是基于同时研究结构动力方程和流体动力方程，即求解流体弹性问题。这个问题，非常复杂，而且形式多样。因为水中结构涵盖海岸、水工、港口、核电、桥梁工程等诸多领域，所以无论其结构形式，还是采用的建筑材料及工作条件，都是千差万别的。若要解答这个问题，就须引用工程地震学、抗震理论、流体动力学的概念，以使计算模型能够真实模拟出结构体系的内部参数分布及其变化，目前为止，虽然我们在这方面已取得了长足的进展，但现在水中结构的抗震动力理论与完善的目标还有一定的距离。由于试验条件所限，对水中结构的模型试验中无限水域场的模拟就是需要解决的困难问题之一，水中振动台的建设可以在很大程度上解决这一问题，通过宽、窄两种水域条件下悬臂结构体系动水压力响应分布和动力特性的试验，作者对水中结构振动台试验问题进行了初步的研究和探讨。 烟囱结构的地震反应及其破坏机理是地震工程界长期讨论的问题，对高耸烟囱结构的模型试验研究是研究此工程问题的重要方法，特别是竖向地震响应特性、水平地震响应特性以及哪种地震输入方向是结构产生破坏的主要控制方向等问题虽有过理论研究，但未有试验验证。本文作者通过对45m和180m高大烟囱结构的动力模型试验，对烟囱结构的地震反应及其破坏机理进行了模型试验研究，得出了有意义的结论，为这一问题的理论研究提供了有力的依据。 应用微粒混凝土材料进行高层建筑的模型试验工作已经是得到普遍使用的事实，但采用有机玻璃(聚丙烯树脂)材料制作结构模型则很少见，本文以聚丙烯树脂材料制作高层建筑结构模型，通过对三座具有不同结构特点的高层建筑的模型试验和原型观测，发现在弹性阶段可以获得比微粒混凝土材料更为丰富的试验参数成果，特别是对于结构应力—应变响应方面能够获得与数模分析十分接近的成果；而且在等效弹性模量前提下可以研究结构弹塑性阶段的动力响应，模型破坏试验结果与实际震害现象也是相当一致的，试验分析与有限元结构计算分析结果的比较表明，聚丙烯树脂材料也是制作高层建筑结构模型的较好模型材料。 总之，试验手段、试验设备条件、模型材料和相似边界条件等都是影响结构体系动力模型试验结果的重要因素，上述问题的研究使模型试验结果愈趋于接近问题的“真解”，物理模型试验也就可以从对问题的定性研究向定量研究方向前进一步。更多还原

【Abstract】 Model test (MT) is an age-old yet important technology in terms of the study on the responses of a structure as well as the regularities of its internal forces and deformations when the structure is subject to various external loads. Even in the context where the computer technology has developed dramatically, MT methods still play an important role in improving structure engineering. With advantages of being able to not only verity the validity and correctness of designing and calculating but also demonstrate directly the state of complex details under given forces, this method is especially indispensable to the study of those problems, for the solutions of which ideal mathematical models could not be constructed.Similitude theory is the premise of MT. By practicing model tests, the author of the dissertation advanced three basic requirements and some skills to keep the similarities between models and prototypes in testing dynamic models and their ruptures, pointing out that there exist differences in similitude requirements according to the different experimental aims, namely, dynamic characteristics, elastic vibration responses and rupture forms as well. Through MTs could be obtained deeper comprehension of and more information about dynamic features of a structure and its rupture activities. The dissertation produced some new concepts on dynamic model testing especially as to certain intricate similitude problems of civil engineering buildings.Selecting model testing materials for a large concrete structure is of great significance to the results of the experiment. This dissertation analyzed the features of low strengthen-emulation concrete materials including their proportions, dynamic natures, as well as field applications. The analysis indicated that simulation materials are perfect for simulating experiments on large-scale structures. The repeatability of the multiple group experiments could make it possible to eliminate some uncertain factors in the course of the experiment. Consequently, the credibility, of the experiment could be guaranteed.Solution of hydro-structures is usually based on researching both hydrodynamic equation and structure dynamic equation. The structure forms, experiment materials and working condition are so complex that we need many concepts such as seismology engineering, aseismic engineering to solve the previously mentioned problems. Water structure covers seashore and coast engineering, hydraulic engineering, harbor engineering, nuclear power engineering and bridge engineering etc. Up to now, we still have a long way to go to the target about aseismic theory of hydro-structure although quiet great progress on it being acquired. We have many difficulties in simulating the distribution and variation of internal parameters of hydro-structures. One of which is how to simulate infinite water area when the hydro-structure model experiment is tested. But now, the situation has been improved since the under water seismic simulating system was constructed successfully. Some hydro-cantilever structure model tests in both widen water and narrow area have been conducted. And the author of this dissertation has finished preliminary research work on the under water shaking table experiments. A long discussed issue in earthquakeengineering is the responding and failure mechanism of chimney structure in the case of earthquake happening. An important and available research method for studying high towering structure is to do model tests. Some topics, such as seismic responding as earthquake comes from vertical or horizontal directions or which direction plays the major role for controlling the rupture of structure, have been discussed by some scholars. But the studies of those topics are short of test-based verification. Some research items have been done by testing 45m and 180m chimney structure dynamic models. And some significant and important results have been obtained from these researching works. Potent and convincing references are found for doing theory research on this engineerin更多还原