【作者】 赵瑜；

【导师】 赵阳升；

【作者基本信息】 太原理工大学 ， 工程力学， 2004， 硕士

【摘要】 边坡问题已变成同地震和火山相并列的全球性三大地质灾害之一。滑坡灾害的出现频度和广度又远远大于地震和火山事件。滑坡的诱发因素很多，但水库诱发的滑坡尤为普遍，水库滑坡大部分发生于蓄水初期。水库蓄水后引起渗流场的变化对库岸边坡的稳定具有严重作用和影响。实际工程中大量岩质边坡的失稳等破坏性灾害事故的发生，不仅仅是一个岩体对水或单纯的水对岩体的作用问题，而是两者的耦合作用。已有的力学理论如单一的岩体力学或渗流力学已不能解决这些复杂的力学现象，更难以指导工程实践，因此建立合理可行的裂隙岩体水力学模型是至关重要的。对于边坡稳定性评价，必须先对边坡渗流场的变化进行充分的了解，在此基础上，才能正确分析边坡的稳定状况，为其稳定性评价和治理工程措施的实施提供坚实基础。 如今三峡水位分四阶段提高水位，最终至正常蓄水位为175 m，在蓄水过程中随着库水位的抬升，必然会引起库岸边坡渗流场的变化，作者把块裂结构岩质边坡看作拟连续介质与块裂介质广义混合介质，运用现代分形理论，建立了1——2级主干裂隙分形网络，并根据两类介质接触处水头相等及节点流量相等建立了合理的块裂结构边坡三维水力学模型，本文就耦合数学模型中的岩体变形方程、裂缝水渗流方程的离散做了详细分析，并给出了具体的表达式，利用PowerStation Fortran 90太原理工大学硕士研究生学位论文计算机语言强大的计算功能，编制了一套块裂介质岩体三维固流祸合数学模型的源程序提出了块裂岩质边坡固、流祸合数学模型的数值解法，基本的求解策略是:将固体变形应力场，流体渗流场看成独立的子系统，祸合迭代求解，对时间采用差分，对空间采用有限元法，并在此基础上，编制了相应的计算机源程序 数值模型模拟了三峡工程的蓄水位至175m时边坡渗流场与应力场的变化，在应用上有较好的可靠性与广泛性。计算结果体现了主干裂隙强导水作用:而拟连续介质由于渗透性较主干裂隙弱，最初水位上升缓慢，水位明显落后于主干裂隙水位，出现水位滞后现象。随着时间增长，主干裂隙水头上升缓慢，而拟连续介质水头上升增快，两者水头差降低。计算结果对于岩质边坡稳定性评估，支护参数选择，合理监控具有重要价值。易变形层位的分布格局(水平、顺向、逆向或斜切)决定坡体的主要变形型式及变形域的规模。而正是这个判断方能揭示坡体的变形、失稳机理。坡体上部位移与下部位移相反，分界点基本上在大裂缝处。不考虑水对裂缝面的物理化学作用，以裂缝面1为滑移面计算边坡的安全系数，从3.63到3.20，安全系数逐步下降了百分之十一点七。以裂缝面2为滑移面计算边坡的安全系数，从3.74到3.82(蓄水后五月)，五月后开始下降，最后达3.56。安全系数开始增加由于水位上升后形成的水荷载，增加了裂缝面的抗剪强度，但随着渗流的进行，又使安全系数递减。 本文最后提出应勘探不同区域的裂隙分布之间或同区域而不同层次的裂隙分布。然后根据勘探资料建立裂隙分形网络方能建立合理的模型，这对于岩质边坡稳定性评估，支护参数选太原理1’大学硕十研究生学位论文择，合理监控都具有重要价值，更是对建立合理的块裂岩质边坡本构关系进行一种有益的尝试。希望能够解决制约边坡稳定分析计算成果可靠程度的瓶颈，改变本构关系的研究远远落后于训算技术的发展这一现状。更多还原

【Abstract】 Slope, volcano and earthquake are global terra disasters. But the happening of slope is more than the other two disasters in frequency and extent. There are too many premium factors for slope, but reservoir place a premium on slope more often. Slope mostly happen in early days of sluice. The fluid field change which is aroused by sluice has important effect on the stability of slope. In fact,it is not only a problem rock affecting water or water affecting rock but a problem of the coupling of the two when disaster happen. The mechanics theory like rock theory and flow theory can not settle the complicated problem, even more difficult to guide engineering. So the reasonable hydraulic model is very important. To estimate the stability of slope, we should know about the change of fluid field at first. We can analyze the stability of slope according to the change. We are able to offer stability foundation for stability estimation and fathering engineering.The normal storage level is 175 m in the Three Gorges Reservoir. During the process of water storing, the rising of reservoir water level will cause the change of the seepage flow field within the slope. I have scattered the distortion equation crack seepage equation of rock mass and come out concrete expression. Ihave worked out a suit of three dimension solid fluid coupling procedure of block rock mass. I have put forward the numerical solution. The basic seeking answer strategy is: that regard solid stress field and seepage field as independent subsystem, coupling change to work out the answer and that use difference on time and use FEM in room. On the basis, I have worked out corresponding computer fountain procedure.So the author set up reasonable seepage model which simulates the change of the seepage flow field within the slope when the water level is up to 175m. The seepage model of block -fracture slope is studied. In order to make the model more reasonable and more effective in application, the author create the seepage model of double porosity media including discrete media and equivalent continuum. Based on the relationship of fracture and engineering mass. 1-2 grade fracture net is considered. .According to the equivalent of pressure of two kinds of media, three dimension seepage model is created by using modern fracture theory and FEM solution is given. After calculating, we can see that main cracks is better than simulated media as seepage media The water press simulated media lag behind main cracks at the first, but they will be the same as time goes on. The part which is easier to change decide the form and magnitude of deformation. The judgement is important because that the deformation can show the slope deform and become unstability. The displacement of the upper is contrary to the one of the underneath and the boundary is along the first main crack. The safe parameter which is based on the first maincrack has deduced 11.7 percent when water level rises,not considering physics and chemistry action. The safe parameter which is based on the second main crack has changed from, 3.74 to 3.82(the fifth month after water level rise ),then down to 3.56.The reason for the increase at first is that the water load increase the cut strength of the crack. But the safe parameter decrease as seepage goes on.The author think that we should make up reasonable model according to the law of crack distribution at different level after proving. It is important for the stability of block slope of rock. I try to settle the bottle neck which does harm to the credibility of calculation result.更多还原