【作者】 张建毅；

【导师】 袁晓铭；

【作者基本信息】 中国地震局工程力学研究所 ， 岩土工程， 2008， 硕士

【摘要】 近年来,具有复杂的横截面和大尺寸横截面的盾构隧道和地下广场等地下结构的数量增长很快,要求在横截面部位进行抗震设计的情况越来越多,但合适的地下结构横向抗震设计方法还未形成。为此,本文主要进行了如下工作:1.阐述了进行土-地下结构抗震研究的必要性;总结了土-地下结构相互作用的震害实例并分析了其几个重要影响因素;评述了现有常用的土-地下结构相互作用分析方法,并指出了优缺点;介绍了目前用于土-地下结构动力计算分析的软件。2.分析了当前地下结构抗震理论分析中各种方法的优劣,指出变形分析应是地下结构地震反应分析的主攻方向;提出了土体中地下结构动力分析的横向应变传递计算模型;给出了应变传递率(STC, Strain Transform Coefficient)的定义,提出了横向应变传递模型需要解决的关键问题,给出了相关公式和计算步骤,对影响因素进行分析并给出了影响大小的初步判断。3.为了实现本文作者提出的地下结构横断面应变传递计算模型的动力计算分析,对适于软弱土大变形的二维非线性动力有限元SD4程序进行了地下抗震适用性改进,并对ANSYS进行二次开发与SD4进行前后处理衔接;验证了本文作者提出的横向应变传递模型的可行性与可靠性。4.以土层应变向结构传递的本文模型为基本出发点,并以STC作为指标,采用改进的SD4程序,分析地震动不同输入(峰值和波形)、土层不同性能(土层软硬和土层厚度)以及地下结构特征(埋深、宽高比)等参数对STC以及地下结构动力响应的影响。5.提出了矩形地下结构动力计算简化方法,给出了相应的计算公式并验证了其可行性和精度。更多还原

【Abstract】 Recently, underground structures such as underground squares and shield tunneling with complicated and large-scale cross-sections, increase so fast that the seismic design for the cross-sections becomes more and more significant. However, proper methodologies of lateral seismic design for underground structures are not well-fledged. Based on this idea, the following points are discussed in this thesis:1. The necessity of seismic design for soil-underground structure interaction is stated first. The seismic risk cases of soil-underground interaction are summarized and some of the influencing aspects are analyzed. Some comments on the existing analytical methodologies of soil-underground structure interaction and their disadvantages are given. Finally some computer software for the soil-underground structure interaction dynamic analysis is introduced.2. The advantages and disadvantages of the underground structure seismic design methods are analyzed and the deformation methodology as the key for the underground structural seismic design is designated. Also the lateral-strain-transform numerical model which is employed in underground structure dynamic analysis is proposed and the crucial points to be solved in the model is illuminated, seeing the formulae and computations respectively. And the estimate for the influence aspects is provided. Furthermore, the strain transform coefficient (STC) is defined.3. The two-dimensional nonlinear dynamic FEM program suitable for the larger deformation of clay, namely home-code SD4, for the seismic design of underground structures is improved. At the same time, ANSYS to link up SD4 on pre-processing and post-processing in order to simulate the lateral-strain-transform numerical model which the author proposed before is redeveloped, as well as the feasibility and reliability of this model is verified.4. On the basic of lateral-strain-transform numerical model, the effects of variation of the parameters including the input earthquake motion, the soil property and soil layer as well as the feature of the underground structure on the STC and the structure dynamic response are investigated by the improved SD4 program.5. A simplified-method which is applicable to the seismic design of rectangle underground structures is proposed. And the formula of this method is given as well as its feasibility and precision is demonstrated.更多还原