混凝土高坝抗震安全评价指标及方法研究

发布时间：2018-06-05 11:32

本文选题：混凝土坝 + 地震响应　；参考：《中国水利水电科学研究院》2017年硕士论文

【摘要】：高坝工程的地震响应及其极限能力是抗震安全评价核心内容,同时,真实地模拟强震作用下混凝土坝损伤破坏过程尤为重要。而进行地震响应分析的基础在于需要全面考虑能够影响到结构性态的各种关键因素,例如模拟混凝土材料性能的本构关系模型,可供参考的全面的抗震安全评价规范体系的及相应指标的建立,坝体-地基-库水之间的相互作用等,本文针对以上三个方面的内容进行研究探讨,主要内容和成果如下:(1)本文综合分析研究了国内外混凝土材料本构关系的相关研究成果,基于损伤理论、塑性理论,并考虑到本构模型的实际应用推广,借鉴现行混凝土结构设计规范推荐的混凝土应力-应变全曲线提出了一种混凝土损伤塑性模型。为进一步研究混凝土坝非线性地震响应奠定了理论基础。(2)研究了 FEPG平台的结构与特点,并基于FEPG平台的元件化工作流程,推到了混凝土结构损伤塑性的静/动力平衡方程的弱解形式,在理论层面论述了损伤本构模型的非线性算法迭代步骤,从而明确了基于损伤模型的算法思路。(3)介绍了粘弹性边界和库动水附加质量理论公式,并基于ABAQUS有限元软件的二次开发脚本接口,自行编写了 Python版本的自动施加程序,通过两个例子的验证说明了所开发程序的合理性和实用性。(4)分析研究了美国水工建筑物设计规范(EREM)基于性能目标的抗震评价方法、评价标准、定量化性能指标,同时对国内外相关成果进行了对比分析。结合现有的高混凝土坝的抗震评估,借鉴先进行线弹性评价,再非线性响应分析的评价思路,引入USACE评价程序和判别准则中的结构需求能力比、超线弹性累计时间等定量化指标,再结合现行规范从坝体关键部位、横缝等方面进行非线性响应修正的分步实施,建立混凝土高坝抗震性能定量化评价框架。研究成果为混凝土坝抗震性能评价提供参考。
[Abstract]:The seismic response and limit capacity of high dam engineering are the core contents of seismic safety evaluation. At the same time, it is very important to simulate the damage and failure process of concrete dam under strong earthquake. The seismic response analysis is based on the need to consider all kinds of key factors that can affect the structural behavior, such as the constitutive relation model, which simulates the performance of concrete materials. For reference, the establishment of comprehensive seismic safety evaluation code system and its corresponding indexes, the interaction between dam body, foundation and reservoir water, etc., are discussed in this paper in view of the above three aspects. The main contents and results are as follows: (1) in this paper, the related research results of constitutive relations of concrete materials at home and abroad are comprehensively analyzed and studied, based on damage theory, plastic theory, and taking into account the practical application and extension of constitutive model. Based on the stress-strain curve of concrete recommended by the current concrete structural design code, a damage plastic model of concrete is proposed. For further study of nonlinear seismic response of concrete dams, the structure and characteristics of FEPG platform are studied, and the component workflow based on FEPG platform is also studied. The weak solution of the static / dynamic equilibrium equation of damage plasticity of concrete structures is deduced. The iterative steps of nonlinear algorithm for damage constitutive model are discussed in theory. The theoretical formulas of viscoelastic boundary and hydrodynamic additional mass are introduced. Based on the secondary development script interface of ABAQUS finite element software, the automatic application program of Python version is written by ourselves. Through the verification of two examples, the rationality and practicability of the developed program are illustrated. The seismic evaluation method, evaluation standard and quantitative performance index based on performance objectives are analyzed and studied in the American hydraulic structure Design Code (EREMM). At the same time, the relative results at home and abroad are compared and analyzed. Combined with the seismic evaluation of existing high concrete dams, the evaluation ideas of linear elastic evaluation and nonlinear response analysis are used for reference, and the ratio of structural demand capacity in USACE evaluation program and discriminant criterion is introduced. Based on the quantitative indexes such as over-linear elastic accumulative time and combined with the existing code, the nonlinear response correction is carried out step by step from the key parts of the dam body and the transverse joints, and a quantitative evaluation framework for seismic performance of high concrete dams is established. The research results provide a reference for seismic performance evaluation of concrete dams.
【学位授予单位】：中国水利水电科学研究院
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TV642.1;TV312

【参考文献】