抽水蓄能电站面板堆石坝的地震永久变形分析

发布时间：2018-08-30 10:14

【摘要】：目前,国家电网公司正在积极推进“一特四大”的电网发展战略,即以大型能源基地为依托,着力发展特高压电网,实现大型煤电、水电、核电、再生能源的集约化开发,优化全国范围内的资源配置。而大型抽水蓄能电站作为电力系统中经济、可靠、容量大、寿命周期长、技术成熟的储能装置,在电力系统特别是智能电网的稳定安全运行起着关键性作用。抽水蓄能电站为了完成其抽水—发电循环,通常有两个水库,称为上水库和下水库,而且上水库多建在山顶,筑坝处的沟口较开阔,地质条件一般较差。面板堆石坝具有施工机械化程度高、工期短、投资省以及对地形地质条件的适应能力强等优点,因此是抽水蓄能电站优先选择的坝型。在“5.12汶川地震”后,大坝的抗震安全备受关注。面板堆石坝由松散颗粒集合体填筑而成,在地震作用下,面板结构可能发生挤压、错台与脱空,堆石结构也可能发生坍塌、震陷等破坏,从而影响面板堆石坝的抗震安全。因此大坝抗震评价即成为面板堆石坝设计的重要内容。目前,基于性能的抗震设计在土木工程领域中已取得长足发展。而基于性能抗震设计的前提是准确预估地震作用下的永久变形。本文针对陕西镇安抽水蓄能电站的下库面板堆石坝,进行了三维有限元静、动力分析。静、动力本构模型分别采用邓肯E-B模型和等效线性-粘弹性模型,采用南科院测得的堆石料动应力与残余应变关系曲线,利用等效结点力法进行了面板堆石坝的地震永久变形分析。其次,讨论了在不同的最大动剪模量以及在不同的动剪模量比衰减曲线和阻尼比增长曲线选取下坝体的动力响应,研究了这些动参数变化对地震永久变形的特征值以及分布规律的影响,得出动参数变化下地震永久变形的变化规律。
[Abstract]:At present, the State Grid Company is actively promoting the development strategy of the "one, four" power grid, that is, relying on a large energy base, focusing on the development of ultra-high voltage power grids, and realizing intensive development of large-scale coal, hydropower, nuclear and renewable energy sources. Optimize the allocation of resources nationwide. As an economical, reliable, large capacity, long life cycle and mature technology, the large pumped storage power station plays a key role in the stable and safe operation of the power system, especially the smart grid. In order to complete its pumped-generation cycle, there are usually two reservoirs, upper reservoir and lower reservoir. Moreover, the upper reservoir is built on the top of the mountain, the gully in the dam is open, and the geological conditions are generally poor. Face rockfill dam has the advantages of high construction mechanization, short construction period, low investment and strong adaptability to topographic and geological conditions, so it is the preferred dam type for pumped storage power stations. After the 5. 12 Wenchuan earthquake, the seismic safety of the dam has attracted much attention. The concrete face rockfill dam is constructed by the loose grain aggregate. Under the action of earthquake, the face slab structure may be squeezed, staggered and emptied, and the rockfill structure may collapse and collapse, thus affecting the seismic safety of the face rockfill dam. Therefore, seismic evaluation of dam becomes an important content in the design of face rockfill dam. At present, performance-based seismic design has made great progress in the field of civil engineering. The premise of performance-based seismic design is to accurately predict the permanent deformation under earthquake action. In this paper, the static and dynamic analysis of three dimensional finite element method is carried out for the concrete face rockfill dam of Zhenan pumped storage power station in Shaanxi province. The static and dynamic constitutive models are respectively based on Duncan E-B model and equivalent linearly viscoelastic model, and the curves of dynamic stress and residual strain of rockfill are used. The seismic permanent deformation of face rockfill dam is analyzed by using the equivalent node force method. Secondly, the dynamic response of the dam is discussed under the different maximum dynamic shear modulus and the different damping ratio growth curve and the attenuation curve of the dynamic shear modulus ratio. The influence of these dynamic parameters on the characteristic value and distribution of earthquake permanent deformation is studied. The variation law of earthquake permanent deformation under the change of dynamic parameters is obtained.
【学位授予单位】：大连理工大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TV641.43;TV312

【参考文献】