混凝土面板堆石坝施工期与蓄水期工作性态研究

发布时间：2018-06-18 18:00

本文选题：面板堆石坝 + 本构模型　；参考：《福州大学》2014年硕士论文

【摘要】：混凝土面板堆石坝由于其工期短、投资省等众多优点而日益受到坝工界的青睐,并逐渐成为一种极具竞争力的坝型。堆石体作为堆石坝的主要组成部分,其本构模型的选择和参数的确定一直是土石坝数值分析的难点。当前,国内面板坝应力变形分析中常用的本构模型主要有邓肯E-B模型、沈珠江双屈服面模型和多重势面模型。由于邓肯E-B模型模拟的面板底部拉应力偏大,沈珠江双屈服面模型模拟的位移值偏小,因此一种能反映面板坝实际应力和应变情况,参数适用性强且力学概念简单的本构模型是有迫切需求的。本文主要工作和成果归纳如下：1.对堆石体邓肯E-B模型、沈珠江模型与多重势面模型进行了评述与分析。基于本课题组提出的多重势面模型选用E-B模型的参数,并且用邓肯模型的加卸载准则来判断多重势面模型的加卸载具有很好的优越性。本文提出沈珠江模型选用E-B模型的参数,并利用自行开发的面板堆石坝的三维非线性有限元程序,以福建仙游抽水蓄能电站上库面板堆石坝为研究对象,进行三维有限元应力变形分析,最后将计算结果与邓肯E-B模型、多重势面模型选用E-B模型的参数、多重势面模型选用沈珠江模型的参数、沈珠江模型选用沈珠江模型的参数、沈珠江模型选用沈珠江模型的参数并且将卸载泊松比取为0.3、沈珠江模型选用沈珠江模型的参数并且q值取(?)进行比较,突出选用邓肯E-B参数的本构模型的优越性。2.程序中有限元方程解法采用中点增量法,模拟坝体逐级施工和蓄水的加载过程。混凝土面板采用线弹性本构模型,面板与垫层之间的接触面、面板垂直缝及周边缝间止水连接均采用古德曼无厚度单元模拟。3.最后将运用E-B参数的三种本构模型计算出的沉降量与实测数据对比,并将面板应力变形值、垂直缝及周边缝开合度与国内外相似工程类比,结果显示选用E-B模型的参数的沈珠江模型和多重势面模型计算的堆石体最大沉降量与实测吻合较好。计算的面板垂直缝周边缝变形值都较小,与同类工程相比均在计算与实测范围内。由此可见,沈珠江模型选用E-B模型的参数在混凝土面板堆石坝的应力变形分析研究中很好的克服了沈珠江双屈服面模型计算的垂直位移偏小,同时也修正了邓肯E-B模型计算的面板底部顺坡向出现较大拉应力的缺点,因此具有很大的发展前景。
[Abstract]:The concrete face rockfill dam is increasingly favored by the dam industry because of its short construction period and low investment, and has gradually become a very competitive dam type. As the main part of rockfill dam, the selection of constitutive model and the determination of parameters are always the difficulties in numerical analysis of rockfill dam. At present, the constitutive models commonly used in the analysis of stress and deformation of slab dams in China include Duncan E-B model, Shen Zhujiang double yield surface model and multiple potential surface model. Due to the large tensile stress at the bottom of the slab simulated by Duncan E-B model and the small displacement value simulated by the Shen Zhujiang double yield surface model, one can reflect the actual stress and strain of the face slab dam. Constitutive models with strong applicability of parameters and simple mechanical concepts are urgently needed. The main work and achievements of this paper are summarized as follows: 1. The Dunken E-B model, Shen Zhujiang model and multiple potential surface model are reviewed and analyzed. Based on the multiple potential surface model proposed by our team, the parameters of E-B model are selected, and the loading and unloading criteria of Duncan model are used to judge the loading and unloading of multiple potential surface model. In this paper, the parameters of E-B model are selected for Shen Zhujiang model, and the 3D nonlinear finite element program of face rockfill dam developed by ourselves is used to study the upper face rockfill dam of Xianyu pumped Storage Power Station in Fujian Province. Three dimensional finite element analysis of stress and deformation is carried out. Finally, the calculated results are compared with Duncan E-B model, multiple potential surface model with E-B model, multiple potential surface model with Shen Zhujiang model parameter, Shen Zhujiang model with Shen Zhujiang model parameter. The Shen Zhujiang model selects the parameters of the Shen Zhujiang model and takes the unload Poisson's ratio to 0.3, and the Shen Zhujiang model selects the parameters of the Shen Zhujiang model and takes the Q value of the model. The comparison shows that the constitutive model with Duncan E-B parameter is superior. 2. In the program, the midpoint increment method is used to simulate the construction of dam and the loading process of water storage. The linear elastic constitutive model is used in concrete slab. The contact surface between the slab and the cushion and the watertight connection between the vertical joint of the slab and the peripheral joint are simulated by Goodman non-thickness element. Finally, the settlement calculated by using the three constitutive models of E-B parameters is compared with the measured data, and the stress and deformation values of face slab, the opening and closing degree of vertical joints and peripheral joints are compared with similar projects at home and abroad. The results show that the maximum settlement of rockfill calculated by using the Shen Zhujiang model and the multiple potential surface model of E-B model is in good agreement with the measured results. The calculated deformation values of the peripheral joints of the vertical joints of the face plate are smaller than those of the similar projects, and are in the range of calculation and measurement. It can be seen that the parameters of E-B model used in Shen Zhujiang model can overcome the small vertical displacement calculated by Shen Zhujiang double yield surface model in the analysis of stress and deformation of concrete faced rockfill dam. At the same time, the drawback of large tensile stress along the slope direction of the bottom of the panel calculated by Duncan E-B model is corrected, so it has a great development prospect.
【学位授予单位】：福州大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TV641.43

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