【作者】 陈英儒；

【导师】 杨强；

【作者基本信息】 清华大学 ， 水利工程， 2008， 博士

【摘要】 高拱坝结构整体稳定性评价、高拱坝坝踵开裂稳定评价、高拱坝坝趾加固设计、高拱坝基础断层的加固处理及岩体力学参数取值问题为高拱坝设计中的关键问题。论文在完善变形加固理论的理论基础之上,采用变形加固理论从变形稳定的角度分别对上述几个问题进行相关的研究工作。论文的主要工作和创新成果如下:1.按照一般的弹塑性理论重新构建了弹塑性结构变形加固理论的理论框架。提出了结构失稳的明确定义,建立了此定义的严格的集合逻辑表述,并以此定义为出发点,推导并证明了变形加固理论的理论基础—最小塑性余能原理。推导表明,最小塑性余能原理是结构平衡条件、变形协调条件和本构关系的集中体现。2.运用变形加固理论,采用工程类比的方法评价高拱坝的整体稳定性。变形加固理论的分析方法是在给定整体安全系数的前提下推求维系结构稳定的不平衡力,塑性余能为结构不平衡力的标量范数,其大小可以反映结构偏离稳定状态的距离,故可评价结构的整体稳定性。从拱坝超载加固的角度评价高拱坝的整体稳定性,建立了高拱坝超载系数K与塑性余能ΔE间的K ?ΔE关系曲线,并以此曲线对国内部分高拱坝的整体稳定性进行评价。3.运用变形加固理论对拱坝坝趾加固设计、断层加固设计及坝踵开裂评价进行研究,实现了坝趾、断层加固力的量化计算及坝踵开裂程度的量化评价。对坝趾加固分析,提出了坝趾加固力的统计方法及便于锚固施工需要的加固力调整方法;对断层加固,根据断层不平衡力的分布和方向,对加固措施的设计和分析进行指导;对坝踵开裂评价,以不平衡力的大小、分布范围和方向评价坝踵可能的开裂程度、开裂范围及开裂模式。4.提出了复合介质强度参数的塑性余能等效方法。推导了复合介质塑性余能的表达式,揭示了复合介质强度参数与变形参数之间的相关性,研究了材料不同配比下复合介质强度参数的变化规律,通过数值计算说明了塑性余能等效方法用于确定复合介质强度参数的可行性。更多还原

【Abstract】 For high arch dams, the key problems include monolithic stability evaluation, cracking evaluation of dam-heel, reinforcement design of dam-toe and faults of dam foundation, and the value of mechanics parameter of rock mass. In this dissertation deformation reinforcement theory is improved on the theoretical framework, and then used in the analysis of above problems. The main research works and innovative achievements include:1.The theoretical framework of deformation reinforcement theory is rebuilt according to the general elasto-plastic theory. The clear definition of structural instability is presented. Based on this definition, the strict expression of logic set is built, and then the theoretical foundation of deformation reinforcement theory, minimum plastic complementary energy principle, is deduced and proved. The deduction shows that the minimum plastic complementary energy principle is centralized reflection of equilibrium condition, deformation compatibility condition and constitutive relation.2.The monolithic stability of high arch dams is evaluated using the deformation reinforcement theory. The analytical method of deformation reinforcement theory is to estimate the unbalanced force to maintain the structural stability on the premise of the given monolithic safety factor. Plastic complementary energy is the scalar norm of unbalanced force and its magnitude reflects the distance which the structure deviate from the stability state, so plastic complementary can be used to evaluate the structural monolithic stability. The monolithic stability of high arch dams is evaluated from the angle of overload and reinforcement, K ?ΔE relation curve between overload coefficient K and plastic complementary energyΔE is established and is used to evaluate the monolithic stability of high arch dams.3.Deformation reinforcement theory is used to guide the reinforcement design of dam-toe and faults and to evaluate the cracking of dam-heel. The quantitative calculation of reinforcement force of dam-toe and faults and quantitative evaluation of dam-heel are realized. For the reinforcement of dam-toe, the statistical method of reinforcement force of dam-toe is presented, and the adjusted method of reinforcement force to suitable for the bolting construction is proposed, too. For reinforcement of faults, the scope and direction of unbalanced force of faults are used to guide the design and analysis of reinforcement measure; For the evaluation of dam-heel cracking, the magnitude, distribution scope, and direction of unbalanced force are used to evaluate the possible cracking extend, cracking scope and cracking mode of dam-heel.4.Complementary energy equivalent method is presented and used to determine the strength parameters of complex. By means of expression deduction of complementary energy of complex, the correlation between deformation parameters and strength parameters of complex is shown theoretically. The change law of strength parameters is researched under the different ratio of materials of complex. Numerical computation shows that the complementary energy equivalent method is feasible to determine the strength parameter of complex.更多还原