箱型深基

发布时间：2018-05-18 04:05

本文选题：箱型基础 + 高层结构　；参考：《合肥工业大学》2017年硕士论文

【摘要】：在各大城市的建设用地日益减少的今天,建筑物只能“上天入地”以增加层面空间。因此,采用箱型深基础的高层结构以其上下兼顾的先天优势越来越多地受到人们青睐。但由于动力相互作用问题的复杂性,相关的抗震设计理论仍存在着极大的滞后,尤其是国内学者的研究,更多的集中在桩基,对于工程中常见的箱型基础则相对较少,为此,我们有必要加强对箱型深基础-高层建筑结构抗震性能的研究。本文以某大厦为工程背景,利用大型通用有限元分析软件ANSYS研究了箱型深基础-高层结构的抗震性能。首先,对地基、箱型基础和上部结构进行了合理的建模,并于施工现场采集了沉降等相关数据,通过重力场下静态分析的计算结果同工程实测数据的比较,验证了所建模型的有效性和准确性;然后,输入ELcentro波、Kobe波和上海人工波作为激励,对地基-箱型基础-上部结构整个动力相互作用体系进行了动力时程分析,研究了相互作用体系中箱型深基础在不同地震激励以及不同工况作用下的位移响应与内力响应、核心筒的影响以及基础与土的接触压力;最后,进一步与刚性地基体系对比,定量探讨了两种模型中结构的自振特性、位移响应、加速度响应和内力响应的区别。主要结论如下:(1)地震时箱基两侧对应测点的位移时程曲线的趋势基本保持一致,表明箱型基础的内部在地震过程中的振动是整体有序的,揭示了箱型基础抗震性能良好的根本原因。(2)核心筒的存在,极大的平衡了箱型基础由形状不规则而引起的各方向刚度的差异,也进一步提高了整个结构体系的整体性,这对建筑结构抗震性能的增强是十分有利的。(3)箱型基础与土之间存在脱离和再接触的现象,表明基础在地震中是不断摇摆的,解释了地震时高层建筑倾斜、倾覆的原因,说明和证实了基础抗倾覆能力的重要性。(4)土与地基的动力相互作用在结构抗震中的减震效果主要表现在建筑的高层,刚性地基假定下高层建筑的抗震设计整体上偏于保守,局部又不安全,考虑地基-箱基-上部结构的动力相互作用来进行建筑结构的设计更符合实际情况。本文的研究成果验证了实际工程设计方案的合理性,为尚未竣工的背景工程后续的抗震优化设计提供了重要的理论依据,同时对于高层建筑结构的防震减灾以及其抗震优化设计理论的完善和发展具有一定的意义。
[Abstract]:With the decreasing of the construction land in the big cities, the buildings can only be built into the sky to increase the level of space. Therefore, high-rise structure with box-type and deep foundation is more and more popular because of its innate advantages. However, due to the complexity of the dynamic interaction problem, there is still a great lag in the relevant seismic design theory. Especially, the research of domestic scholars focuses more on pile foundation, and the box foundation is relatively less common in engineering. It is necessary to strengthen the study of seismic performance of box-type deep-foundation-high-rise building structures. Taking a building as the engineering background, the seismic behavior of box deep foundation-high-rise structures is studied by using a large general finite element analysis software ANSYS. First of all, the foundation, box foundation and superstructure are modeled reasonably, and the settlement data are collected at the construction site, and the calculated results of static analysis under gravity field are compared with the measured data. The validity and accuracy of the model are verified, and the dynamic time history analysis of the whole dynamic interaction system of ground-box foundation-superstructure is carried out by inputting ELcentro wave and Shanghai artificial wave as excitation. The displacement response and internal force response of box deep foundation under different earthquake excitation and different working conditions, the influence of core tube and the contact pressure between foundation and soil in the interaction system are studied. The difference between the natural vibration response, displacement response, acceleration response and internal force response of the two models is discussed quantitatively. The main conclusions are as follows: (1) during the earthquake, the trend of displacement time history curves corresponding to the measured points on both sides of the box foundation is basically the same, which indicates that the internal vibration of the box foundation is orderly during the earthquake. It reveals the root cause of the good seismic performance of the box foundation. The existence of the core tube balances the stiffness difference in all directions caused by the irregular shape of the box foundation, and further improves the integrity of the whole structure system. This is very beneficial to the enhancement of seismic performance of building structure. The phenomenon of separation and re-contact between box foundation and soil indicates that the foundation is rocking constantly in earthquake, which explains the reason why high-rise building tilted and capsized during earthquake. It is proved that the dynamic interaction between soil and foundation in the seismic response of the structure is mainly reflected in the high-rise building, and the seismic design of the high-rise building under the assumption of rigid foundation is conservative in the whole. Considering the dynamic interaction between foundation, box foundation and superstructure, it is more suitable for the design of building structure. The research results of this paper verify the rationality of the actual engineering design scheme and provide an important theoretical basis for the subsequent seismic optimization design of the background engineering that has not yet been completed. At the same time, it has a certain significance for the earthquake prevention and mitigation of high-rise building structure and the perfection and development of the theory of seismic optimum design.
【学位授予单位】：合肥工业大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TU473;TU973.31

【参考文献】