戈兰滩水电站6#坝段渗水问题的有限元分析

发布时间：2018-03-22 20:50

本文选题：工程水力学　切入点：混凝土坝　出处：《天津大学》2014年硕士论文　论文类型：学位论文

【摘要】：水利工程特别是大中型水电站的迅速发展，对于混凝土重力坝除了要考虑地基变形和稳定性等一般问题，还需要考虑流体渗流带来的影响。本文针对戈兰滩水电站6#坝段渗水问题，以渗流基本理论、渗流有限元方法计算理论为基础，以ANSYS软件热处理模块为依托，分析戈兰滩水电站6#坝段渗流场分布情况。结合现场监测数据反演分析现实工况下地基渗透系数，通过对比帷幕深度变化及帷幕形式改变对地基渗流的影响，提出解决戈兰滩水电站6#坝段渗水问题的工程优化方法。这对分析解决同类工程实际问题具有重要的指导意义及经济效益意义。本文主要研究内容：（1）结合现场监测数据，采用ANSYS热处理模块，在现状戈兰滩水电站6#坝段设计条件下，通过假设一系列地基渗透系数值，得到一系列对应的渗流量值，进而得到渗透系数与渗流量的关系曲线。对比现场监测渗流量值，反演分析得到综合情况下的地基渗透系数，该渗透系数即为经过多年的运行后该坝段的实际渗透系数。（2）分析地基无帷幕及有帷幕时对坝段渗流的影响。当坝基设置防渗帷幕时，保持现状帷幕形式不改变，帷幕深度变化取0m~90m时，分析防渗帷幕深度的改变对坝段渗流场的影响；改变帷幕形式（坝基下帷幕最大深度与最小深度处于同一高程），帷幕深度变化取0m~90m时，分析防渗帷幕形式的改变及深度的改变对坝段渗流场的影响。得到在渗流效果一致的情况下，改变帷幕形式（坝基下帷幕最大深度与最小深度处于同一高程）将比现状帷幕形式帷幕方量大大减小。提出继续对坝段单孔渗流量进行观测，选择低温季节进行帷幕补灌浆，灌浆时将原来灌浆深度坝基下不足40m的地方补灌达到40m的渗控方法。（3）分析地基无帷幕及有帷幕时对坝基扬压力水头分布的影响。在对坝基扬压力分析的过程中充分考虑了坝体排水孔的作用。得出设置帷幕灌浆后，，坝基扬压力水头值大幅度减小，减小值约30%。帷幕形式的改变对坝基扬压力水头值影响较小。
[Abstract]:With the rapid development of water conservancy projects, especially large and medium-sized hydropower stations, the influence of fluid seepage on concrete gravity dams should be considered in addition to the general problems such as foundation deformation and stability. In this paper, based on the basic theory of seepage, the calculation theory of seepage finite element method and the heat treatment module of ANSYS software, the seepage problem of dam section No. 6 of Gangtan Hydropower Station is discussed. The distribution of seepage field in dam section 6 # of Gorantan Hydropower Station is analyzed. The seepage coefficient of foundation under actual working condition is analyzed by using the field monitoring data. The influence of the change of curtain depth and the change of curtain form on the seepage flow of foundation is compared. The engineering optimization method to solve the seepage problem of dam section 6 # of Gorantan Hydropower Station is put forward, which has important guiding significance and economic benefit significance for analyzing and solving the practical problems of similar projects. The main research contents of this paper are as follows:. 1) combining with the field monitoring data and adopting ANSYS heat treatment module, a series of corresponding seepage values are obtained by assuming a series of foundation permeability coefficient values under the design conditions of the dam section 6 # of the current Gorantan Hydropower Station. Then the relationship curve between permeability coefficient and seepage discharge is obtained, and the seepage coefficient of the foundation is obtained by inversion analysis, which is the actual permeability coefficient of the dam section after many years of operation. 2) analyzing the influence of foundation without curtain and curtain on seepage flow of dam section. When the dam foundation sets impervious curtain, the form of curtain remains unchanged and the depth of curtain is changed by 0m~90m, the influence of the change of depth of impervious curtain on seepage field of dam section is analyzed. Changing the form of the curtain (the maximum depth and the minimum depth of the curtain under the dam foundation are in the same elevation, and the variation of the curtain depth is taken as 0m~90m, The influence of the change of seepage curtain form and depth on seepage field of dam section is analyzed. Changing the curtain form (the maximum depth and the minimum depth under the dam foundation are at the same elevation) will be greatly reduced compared with the current curtain form. It is proposed to continue to observe the seepage flow of single hole in the dam section and to select the low temperature season for curtain filling grouting. During grouting, the seepage control method is used to control the depth of grouting in places that are less than 40 m below the dam foundation and the depth of grouting is less than 40 m. 3) analyzing the influence of the foundation without curtain and when there is curtain on the distribution of the pressure head of the dam foundation. In the analysis of the uplift pressure of the dam foundation, the function of the drainage hole of the dam body is fully considered. The water head value of dam foundation uplift pressure decreases by about 30. The change of curtain form has little effect on dam foundation uplift pressure head value.
【学位授予单位】：天津大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TV223.4;TV543

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