土石坝易劈裂面与零位移面的相关性研究

【作者】 任红云；

【导师】 潘维宗；

【作者基本信息】 山东大学 ， 水工结构工程， 2006， 硕士

【摘要】 劈裂灌浆技术是我国近年来研究成功的处理病险堤坝经济而有效的一项新技术，属我国首创，在我国病险堤坝防渗加固中发挥了重要作用。劈裂灌浆技术不论在施工工艺还是在理论研究方面取得了不少进展，但是还存在很多问题。 根据土坝坝体的应力分布情况，利用水力劈裂原理，在坝轴线附近沿小主应力面布置灌浆孔，泥浆就容易沿这个平面将坝体劈开，这个容易发生劈裂的平面，我们称之为“易劈裂面”。易劈裂面的位置，根据传统的劈裂灌浆理论就是坝体轴线位置。但是大量的工程实践证明，易劈裂面的位置并不一定在坝体轴线位置。 当土坝在沉降固结过程中，产生竖向沉降和水平位移，上游坡向上游位移，下游坡向下游位移，在横剖面上坝轴线位置存在一条线在水平方向上不发生水平位移，此线沿着坝的轴线形成面，我们称此面为“水平零位移面”，简称“零位移面”。易劈裂面和零位移面存在着一定的关系，出现零位移的位置容易产生裂缝，也就是容易发生劈裂的位置。 本文针对土坝进行不同型式的坝体进行有限差分数值分析，运用流固耦合分析理论来模拟坝体在不同排水条件及不同蓄水位等各种情况下，坝体的位移及应力的变化情况，分析了坝体水平位移、垂直位移、最大最小主应力等指标，其中主要分析不同情况下水平位移的变化，从而分析零位移面的变化，结合坝体的应力状态，确定易劈裂面与零位移面的相互关系。 本文通过研究土石坝易劈裂面和零位移面的关系，确定易劈裂面的产状，为劈裂灌浆轴线的选择提供依据；当坝体下部有其他防渗工程时，调查清楚易劈裂面位置和产状，便于灌浆帷幕和其它防渗帷幕相连。本文旨在提出一种具有普遍适用意义的方法，为劈裂灌浆防渗加固工程的施工提供指导，减少工程施工的盲目性，为工程节约成本，同时进一步推动其理论的发展，为劈裂灌浆技术的推广应用提供更有利的条件。更多还原

【Abstract】 Anti-seepage reinforcement technology of splitting grouting, firstly made in our country, is a successful new technology that can handle the dangerous dam economically and effectively in recent years. The technology has taken an important part in anti-seepage reinforcement of ill dam. Though there have been a lot of progress both in the construction process and in theoretical research, there are still many problems.According to the stress distribution in the dam, using the principle of hydraulic splitting, mud will split the dam easily along the face with grouting bores laid alongthe minimum stress face near the dam axis. We call the very face "face easily split". The location of the face easily split along is along the dam axis based ontraditional splitting grouting. However, a large number of projects prove that the location does not necessarily along the axis.The essay analyzes the changes of stress field and seepage field in the dams of different patterns with finite-difference method, considering gravitation only and with different water storage levels under different drainage conditions. The analyses of horizontal and vertical displacement and maximum and minimum main stresses are given in the essay with the horizontal displacement as an emphasis. Thus the location and shape of the face easily split along are determined and illustrated.The research of the face easily split results in a number of universal conclusions, which provide the warrant for the choice of grouting axis and guidance for construction. In the mean time, it is also propitious to connect with other ant-seepage reinforcement works below the dam, as well as cost savings for the project. While promoting its further theoretic development, it will extend the use of technology.更多还原