堆石混凝土重力坝监测资料的正反分析和安全评价

【作者】 杨倩；

【导师】 赵青；

【作者基本信息】 贵州大学 ， 水利工程， 2022， 硕士

【摘要】 堆石混凝土筑坝技术属于新兴的大体积混凝土筑坝技术,具有结构强度高、耐久性好、施工速度快、经济效益高等优势。该技术已经广泛运用于国内外实际工程,但鉴于堆石混凝土筑坝技术问世时间较短,各项基础理论研究还不够完善,针对其监测资料的正反分析和安全评价方面的工作尚未开展,缺少系统理论研究成果来验证大坝运行的可靠性。大坝一旦失稳,将会造成重大伤亡事故和巨大国民经济损失。如何科学评估堆石混凝土坝的运行状况,以采取相应的工程措施进行防范和处理,具有重要的研究意义和广阔的应用前景。基于此,本文收集了贵州省第一座堆石混凝土坝-打鼓台堆石混凝土重力坝的运行监测资料,首先论述了现阶段大坝监测资料分析的通用方法和基本步骤,利用数学统计方法、渗流力学、有限元法等基本理论,建立了打鼓台堆石混凝土重力坝数理统计模型、确定性模型、混合模型、渗流模型和有限元模型,本文的主要内容有:1.介绍了构建堆石混凝土坝数学模型的基本理论和方法,根据打鼓台堆石混凝土重力坝变形监测资料,利用SPSS分析软件,建立了堆石混凝土重力坝LD3测点上下游及左右岸水平位移的数值统计模型。2.建立了打鼓台堆石混凝土重力坝LD3测点上下游及左右岸水平位移的变形确定性模型和混合模型,引入调整系数,并通过反演得到了坝体的平均弹性模量。3.利用MIDAS GTS NX软件结合坝体、坝基的参数与性态,建立打鼓台堆石混凝土重力坝渗流模型,针对四种不同工况分析总结了堆石混凝土重力坝的渗流规律,并对已布设的防渗系统作出了评价和建议。4.通过ANSYS有限元软件建立了打鼓台堆石混凝土重力坝模型,研究了在正常蓄水位、设计洪水位以及校核洪水位三种工况下大坝的变形和应力-应变的分布及变化情况,并利用有限元法与传统刚体极限平衡法分别计算抗滑稳定安全系数,发现用前者对堆石混凝土重力坝进行安全评价是合理、可行的,且结果具有可视化等优点。更多还原

【Abstract】 Rock-filled concrete(RFC)dam technology belongs to a new mass concrete dam technology,which has the advantages of high strength,good durability,fast pouring speed and reasonable economy.The technology has been widely used in practical engineering at home and abroad,but due to the rock-filled concrete dam technology appear short time,the theoretical research is not perfect,for the monitoring data analysis and safety evaluation has not been conducted,the lack of theoretical research to verify the reliability of the dam operation.Once the dam is unstable,will cause heavy casualties and serious national economic losses.How to judge the operation condition of the rockconcrete dam and take the prevention and treatment of the concrete dam has important research significance and broad application prospect.Based on this,this paper discusses the general method and basic steps of dam monitoring data analysis,using mathematical statistical methods,seepage mechanics,finite element method and other basic theories,to establish the mathematical statistical model,deterministic model,mixed model,seepage model and finite element model of Dagutai rock-filled concrete gravity dam.The main contents are:1.The basic theory and method of the construction of the mathematical model of the rock-filled concrete dam are introduced.According to the deformation monitoring data of rock-filled concrete gravity dam,the numerical statistical model of rock-filled concrete gravity dam is established.2.The deformation deterministic model and hybrid model of the horizontal displacement of the peak measuring point of the rock-filled concrete gravity dam are established,and the average elastic modulus of the dam is obtained by inversion.3.Combined with the parameters and characteristics of the dam foundation,the seepage model of the rock-filled concrete gravity dam is established,and the installed anti-seepage system is evaluated and suggested.4.The distribution and change of displacement and stress strain of finite element model under different working conditions are discussed,and the anti-skid stability coefficient is calculated by finite element method and the traditional rigid body limit balance method.It is found that it is reasonable and feasible to use the safety evaluation of rock-filled concrete gravity dam,and the results have the advantages of visualization.更多还原