【作者】 肖志奎；

【导师】 蒋沧如； 李书进；

【作者基本信息】 武汉理工大学 ， 结构工程， 2004， 硕士

【摘要】 筒体结构作为建筑结构的一种形式，因其可以提供灵活的大空间、结构受力合理而在高层建筑中得到广泛应用，它的出现将高层建筑推向了一个新的历史时期。桩筏基础同时具有桩基础和筏板基础的优点，桩一筏共同承担建筑物的荷载，它具有整体性好、竖向承载力高、基础沉降小、调节不均匀沉降能力强的优点，同时可以承受风荷载或地震荷载引起的巨大水平力，抗倾覆能力强。因此，对筒体结构桩筏基础计算理论进行研究有着很大的社会效益和经济效应。 基础工程计算分析的正确程度主要取决于地基模型和计算参数的选择；筒体上部结构与地基、桩筏三者相互联系处于一个共同作用的完整系统中并且发生变形。在本文中，我们就地基模型和计算参数选择进行了详细的介绍，并用共同作用分析方法对该系统进行了分析，且建立了共同作用的矩阵法方程。 有限元法作为一种离散化的数值方法，是一种近似方法，其理论基础是变分原理。桩筏基础筏板的设计、计算采用厚板理论分析，主要用厚板有限元法来分析筏板的受力、变形特点。关于桩筏基础桩基的研究，本文也采用弹性力学和有限元法相结合进行分析，其分析方法与厚板有限元法基本相似，另外，我们还对结构分析软件ANSYS进行了简介。 本文选用八节点六面体单元对桩筏基础筏板和桩基进行分析，重点介绍了用八节点六面体单元对桩筏基础筏板的分析。在分析时，本文将钢筋混凝土上部结构和地基、基础的研究问题视为各向同性空间问题，且按静力等效原则计算等效节点荷载，荷载列阵由单元等效结点力和直接作用于单元结点上结点荷载集成而得。更多还原

【Abstract】 As a kind of layout plan, tube structure is widely applied due to its commodious room and reasonable structure loading. Its appearance has brought high-rise building into a new history period. Piled raft foundations have advantages of pile and plate foundations. Pile and raft take the load of buildings together. It possesses good whole, high vertical capacity, small settlement of foundation and well performance of balancing differential settlements. It could bear large wind or seismic induced horizon load, and could have large capacity of resisting inclination. Therefore, the study of calculating method on tube-structure piled raft foundation has great social effects and economical profits.Corrective level of calculation and analysis on foundation projects is determined by the choice of subsoil model and computation parameter for subsoil models, and there is the interaction of tube upper structure -piled raft-subsoil system. In this paper, we introduce in detail some kinds of views how to choose subsoil models correctly and how to determine computation parameters for subsoil models, and we analyze their system with reaction theory and establish balancing matrix equation of pile-raft interaction.As a kind of dispersed numerical value method, the finite element is of approximate methods, and is based on principle of variation. In designing and calculating plate of piled-raft foundation, thick-plate theory has been applied, that is, thick-plate finite element method is mainly used when load and deformation of plate are analyzed. On research of piled foundation, elastic mechanics and finite element method are also used in this paper, its analyzing method is elementarily similar to thick-plate finite element. Furthermore, structural analyzing software ANSYS is briefly introduced in this paper.In this paper the 8-nodes 6-planes solid element (solid45) is applied toanalyze plate and pile, and we give priority to analyzing plate. When reinforced concrete upper structure-piled raft -subsoil system is studied, every part of this system is looked upon homogeneous discrete space. Accofding to static equivalent principle, equivalent node loads are calculated, and load embattle is integrated with element equivalent node force and directly bearing load更多还原