【作者】 杨海英；

【导师】 陈刚； 张志昌；

【作者基本信息】 西安理工大学 ， 水力学及河流动力学， 2005， 硕士

【摘要】 地基渗流控制不当是导致闸坝发生渗流事故和破坏的重要原因,对闸坝地基进行渗流计算与分析具有十分重要的实际意义。近年来关于闸坝的渗流计算已不鲜见,但应用有限体积法进行渗流计算的相关报道并不多见。本文应用有限体积法,对闸坝地基的渗流与防渗工程措施进行了研究。 本文首先介绍了有限体积法,并对程序进行了精确解的验证,回顾了砂砾石地基的渗流控制措施、原则及基本要求。在实际工程中,铺盖和防渗墙是泄冲闸及其它水工建筑物防渗经常采取的措施,二者的防渗效果和工程造价均有差别。本文结合金沙峡电站闸基防渗方案,对铺盖和防渗墙的组合问题进行了研究,得到了铺盖长度、防渗墙个数、防渗墙深度和防渗墙相对闸基的位置四个因素的最佳组合。 帷幕和排水是混凝土重力坝坝基渗流控制的主要措施,本文分别针对只有帷幕和只有排水以及两者联合作用的情况进行了研究。只有主帷幕作用时,对于隔水层较深和隔水层较浅的情况,得到了帷幕的合理深度。对于隔水层较深的情况,还分析了帷幕的厚度和位置对于坝基渗流量和扬压力的影响。只有主排水作用时,得到了排水孔作用效果的决定因素,得出了排水孔的设置也应有一个合理深度的结论,还分析了排水孔孔径、间距对渗流量和扬压力的影响。对于二者联合作用的情况,分析了排水孔深度一定时,增加帷幕深度对渗流量和扬压力的影响。帷幕深度一定时,分析了排水孔深度的变化对渗流量和扬压力的影响。~一一一一一一一一一一J理里理夔 本文对泄冲闸基底进行了排水孔失效二维计算、排水孔有效二维计算、排水孔有效三维计算和对排水孔处进行网格自适应的三维计算。结果表明,后两种方案由于计算模型准确,网格划分细密,计算结果比前两种方案可靠,且排水孔处网格的划分对于整个渗流场的计算具有十分重要的意义。对土坝和泄冲闸的结合部位渗流场进行了考虑土坝坝体渗流和不考虑土坝坝体渗流的两种方案的计算。对于前一种方案实现了整个渗流场的纵向和横向流态的计算。对于后一种方案,对排水孔处进行了网格自适应,大大增加了计算结果的可靠性。关键词:闸坝渗流场 网格自适应有限体积法帷幕排水孔更多还原

【Abstract】 Bad foundation seepage control results in many seepage accidents, so it is very important to research foundation seepage of gate dam. It is lack of numerical simulations by finite volume method though there are a lot of numerical works using other methods. Foundation seepage and seepage control of gate dam are investigated in combination with Jinshaxia hydroelectric power station in this paperFirst, finite volume method is introduced, and exact solution is validated. Measures, rules and basic demands of seepage control is reviewed about grit foundation. Usually, impervious blanket and impervious wall are adapted for seepage control of gate dam and other hydraulic structures in projects. The seepage control effect and project cost are different. In this paper, the combination of them is studied, and the best combination of impervious blanket and impervious wall is found.Usually, curtain and drainage are adapted for seepage control of gravity dam, and they are studied in this paper. In case of setting curtain merely, its reasonable depth is found for deep impervious blanket and shallow impervious blanket is discussed. The effect of thickness and place of curtainon seepage discharge and uplift of dam foundation for deep impervious blanket are analyzed. In case of setting drainage merely, determinant of the effect of it is found. The conclusion is educed that there is a reasonable depth when drainage is set and the effect of drainage diameter and drainage space on seepage discharge and uplift of dam foundation is studied. In case of setting drainage and curtain together, the effect of increasing curtain depth on seepage discharge and uplift of dam foundation is studied when drainage depth is fixed. The effect of increasing drainage depth on seepage discharge and uplift of dam foundation is studied when curtain depth is fixed.In this paper, the four projects are calculated for sluice foundation, and that is two-dimensional calculation taking into drainage, two-dimensional calculation taking no account of drainage, three-dimensional calculation taking into drainage and three-dimensional calculation using grid adapt around drainage. The result makes it clear that it is very important that grids around drainage are set off reasonably for calculating seepage field. For the joint part of earth dam and sluice foundation, the two projects are calculated, that is taking into earth dam body seepage and taking no account of earth dam body seepage. For the former, the longitudinal and cross flow patterns of the whole seepage field are calculated. For the later, reliability is increased by. adapting the grids around drainage.更多还原