【作者】 戚建邦；

【导师】 柴军瑞；

【作者基本信息】 西安理工大学 ， 水工结构工程， 2009， 硕士

【摘要】 裂隙岩体渗流场与应力场耦合研究是岩体水力学中一个很有意义的课题。裂隙岩体渗流特性主要由岩体裂隙网络结构决定。裂隙隙宽的改变引起对裂隙渗流的影响,而渗流场变化反过来引起岩体应力场变化,即为渗流与应力的耦合作用。在隧道工程施工过程中,隧道围岩中渗流场与应力场存在着耦合关系。本文在国内外研究的基础上,根据裂隙网络岩体渗流场与应力场耦合的基本理论,对隧道开挖后衬砌前裂隙围岩在二次应力和敞开排水状态下的渗流场与应力场进行耦合计算。研究成果主要有以下几个方面：1、分析现有岩体渗流场与应力场耦合模型,总结各种数学模型的优缺点及其适用范围。吸收现有岩体水力学在该领域的研究成果,分析应力与隙宽、渗透力等之间的关系,建立耦合分析模型；2、使用裂隙网络数学模型对裂隙网络岩体进行渗流场与应力场的耦合计算,根据离散网络模型的基本理论,编制计算程序,并通过算例对程序进行了验证。3、隧道工程施工过程中,存在着渗流场与应力场的耦合关系。对隧道工程施工过程中渗流场与应力场的耦合机理进行研究。以裂隙岩体渗流场与应力场耦合模型为基础,建立隧道开挖过程中渗流场与应力场耦合模型；4、用所编制的程序,在考虑中部开挖的情况下,对裂隙网络岩体进行渗流场与应力场的耦合计算,从计算结果可以看出,开挖后的岩体渗流场与应力场,在耦合与不耦合情况下有所不同。渗流场对应力场的影响,在靠近开挖区域较为明显。与开挖部位相连通的裂隙渗流量,在考虑耦合作用影响下有所减小；5、对某隧道工程开挖后、衬砌前,围岩在二次应力和敞开排水(不考虑衬砌与防排水措施)条件下的渗流场与应力场进行了耦合计算。由计算结果看出,隧道开挖后,在隧道周围出现应力集中现象。考虑耦合作用时,应力场对渗流场的影响大于渗流场对应力场的影响,在应力场的影响下,隧道围岩内裂隙闭合,裂隙内水头增加,对与隧道连通裂隙的渗流量进行计算,考虑耦合作用后,裂隙向隧道内的渗流量减小。在渗流场影响下,围岩最大主应力增大,但增大值相对较小,且集中在隧道周边部位。更多还原

【Abstract】 Coupled analysis research of unsteady seepage and stress in fractured rock masses is a very valued task for discussion. The seepage in rock mass mainly reflected as fracture flow. With the changing of boundary hydra-head, the width of the fracture increased or reduced, which affects the fracture flow. Conversely, the change of seepage field affects the stress field. The interaction of the two filed is called coupling. on tunnel construction process, there is coupied interaction between seepage and stress fields. On the basis of existing studies in the field of seepage of rock mass both at home and abroad, according the basic theory of coupled seepage and stress fields, the thesis has conducted a broad study of coupled seepage and stress fields on tunnel surrounding rock mass between excavation and lining step. The main researches as follows:1. Analyzed the exist model of coupled seepage and stress field. Summarizes the advantage and disadvantage and applicable scope of every model. Based on study properties of rock mass mechanics, analysis the relationship between stresses and osmotic ratio, and created the model of coupling;2. Discrete fracture network method is used in couple field. According the basic theory of discrete fracture network method, edit the calculating program, check the program with a example;3. In tunnel construction process, exist the interaction between seepage and stress field. Analysis the mechanics of seepage and stress interaction in tunnel construction process. At the basic of rock mass couple field theory. Build the couple field model of tunnel rock mass at excavation step;4. Use edited program, calculating the seepage and stress field of fracture rock mass at the condition of excavation. The result show that, when considering of couple effect, seepage and stress field are all different from when not considering the couple effect. The effect to stress field is significantly near the excavation area. Seepage discharge is redused under couple effect; 5. Calculating A tunnel seepage and stress field under secondary stress and drainage condition between excavation and lining step. The result show that, after excavation,near excavation area appeared stress-focus phenomenon.When considered couple effect, the influence to seepage field is more obviously then to stress field.When consider the stress field influence,the fracture closed, hydraulic head increased, the quantit of water inflow reduced. Consider the couple effect, max tensile stress is increased near the tunnel area, but the added value is less.更多还原