【作者】 吴川；

【导师】 耿萍；

【作者基本信息】 西南交通大学 ， 桥梁与隧道工程， 2013， 硕士

【摘要】 水电梯级开发规划促推了我国兴修水利的新一轮高潮,多座水电站应运而生,在水工建设中水工隧洞举足轻重。然而修建长大水工隧洞的过程中,可能遭遇多种复杂不利地质情况,突水突泥的情况时有发生,尤其在断裂破碎带附近突水突泥更为严重,给隧洞施工和周边环境带来极大的威胁。本文依托木里河流域水电工程水工隧洞进行针对性的研究,通过资料调研、理论研究与数值模拟等方式,对不同类型的突水突泥做出了宏观和细观机理的研究,探讨了影响隧洞施工过程中突水突泥的主要因素。基于地质构造、岩溶及水文地质条件、围岩性质三方面的分析,对不同地质环境下的突水突泥现象进行分类,确立研究的对象。在此基础上对不同类型突水突泥过程进行现象解释,力学分析,得到突水突泥宏观规律,为后面的数值模拟提供依据。根据隧洞施工突水突泥分类,结合颗粒流模拟流固耦合方法,考虑数值方法的适用范围,选用平均中尺度粗糙网格法与虚拟“域”—“通道”法来建立不同类型突水突泥的数值模型,然后分别阐释不同流固耦合数值模型的理论基础和实现方法。针对不同类型的突水突泥过程进行模拟和机理研究。首先通过PFC内置系统标定围岩的物理力学参数和水力学参数,建立细观与宏观的联系,同时改变细观组构来模拟不同结构类型的岩体特征；再根据不同突水突泥的类型,分别建立了蚀溃型和劈裂型颗粒流二维模型。最后按散体结构岩体(Ⅴ类围岩)、单节理裂隙岩体(Ⅳ类围岩)、较完整岩体(Ⅲ类围岩)三种围岩环境,模拟各自突水突泥的发生,发展至破坏的过程,研究其机理。结果表明：不同围岩环境与隧洞施工突水突泥类型密切相关,不同渗流场与应力场耦合方式影响突水突泥过程,即蚀溃型突水突泥与劈裂型突泥突水,其过程中的孔隙率变化、裂隙分布、突水突泥量规模、位移大小、突水通道的空间定位各异,其破坏形式存在差别。考虑单因素单独作用对突泥突水的影响,模拟单因素变量改变的突泥突水过程,对比因素变化对宏观现象和细观机理带来的改变,由此确定一定环境条件下的临界破坏状态,提出相应的临界值,为实际工程提供参考。更多还原

【Abstract】 The hydropower cascade development promote a new round high tide of building hydropower engineering in my country,then a large number of hydropower stations were born at the right momen.Hydraulic tunnel is extremely important to hydraulic construction. However.it my encounter a variety of complex and unfavorable geological conditions in the process of building the hydraulic tunnel.The wate-mud-inrush is especially more serious in the fractured zone and bring great threat for tunnel construction and surrounding environment.In this thesis,different types of water-mud-inrush’s macroscopic and mesoscopic mechanism are researched through information Investigate, theoretical study and numerical simulation which are based on the hydraulic tunnels of Muli river.The major factors that influence mud-water-inrush in the process of tunnel excavation are discussed.Based on geological structure, karst, hydro geological condition and rock property, the macro phenomenon of water-mud-inrush are classified and the research objects is established.For providing the basis for the numerical simulation.it need phenomenon explain,mechanics analysis and theoretical calculation in foundation of classifications to get the macroscopic rule of water-mud-inrush.According to the type of water-mud-inrush in the process of tunnel construction, illustrate the theoretical basis and implementation method for different numerical model of fluid-structure coupling after combining methods on particle flow simulation of fluid-structure interactionxonsidering the applicable scope of numerical method.matching suitable numerical models for different types of water-mud-inrushTo simulate and mechanism research different types of the water-mud-inrush process:Firstly calibrate mechanical parameters and hydraulics parameters of surrounding rock by PFC built-in system to established mesoscopic and macroscopic connection while change micro-structure to modelling different structural types of rock mass characteristics;According to different types of water-mud-inrush,established two dimensional erosive and split particle flow model separately.Different types of water-mud-inrush process are respectively calculated according to the surrounding environment which is loose structure mass (grade V),single joint fractured rock mass(grade IV) and complete rock mass (grade III).Study mechanism and find that the type of water-mud-inrush in the progress of tunnel construction is closely related to the surrounding rock;the different way seepage and stress fields coupled affect water-mud-inrush process which indicate that there is big difference on porosity change,fracture distribution,water-mud-inrush scale,displacement,spatial orientation of water inrush channel and failure mode between erosive and split water-mud-inrush.Considering different human and environmental factors influence on water-mud-inrushucompare the change on macroscopic phenomenon and mesoscopic mechanism caused by factor varied.Then determine the critical damage condition and critical value.It provide the reference for tunnel construction.更多还原