含自由面岩体裂隙网络非线性渗流分析的传导矩阵调整法  

The conductivity matrix reforming method about non-linear seepage with free surface in fracture network of rock mass

作　　者：徐维生[1] 柴军瑞[1,2] 陈兴周[1,3] 

机构地区：[1]西安理工大学水利水电学院,西安710048 [2]三峡大学土木水电学院,宜昌4430023 [3]中国水电顾问集团西北勘测设计研究院,西安710065

出　　处：《水动力学研究与进展（A辑）》2010年第4期484-492,共9页Chinese Journal of Hydrodynamics

基　　金：教育部"新世纪优秀人才支持计划"资助项目(NCET-05-0679);教育部博士点基金(20096118110007);湖北省青年杰出人才基金项目(2004ABB012);湖北省"楚天学者计划"特聘教授资助项目(603108);三峡大学科技创新团队资助项目(603402);西安理工大学优秀博士学位论文研究基金(106-210913)

摘　　要：岩体裂隙网络渗流自由面不同于连续介质渗流自由面。自由面问题是渗流区域非线性问题,需要通过迭代求解。很多裂隙渗流是非线性渗流,求解属于渗流本构关系非线性问题,同样需要迭代求解。有渗流自由面的非线性渗流问题属于渗流区域和本构双重非线性问题,必须通过双重迭代求解。分析单裂隙非线性渗流规律,在此基础上利用裂隙水量平衡原理建立结点水头数值方程;参考确定连续介质渗流自由面的固定网格法,对岩体裂隙网络全区域的裂隙渗流参数进行分析,利用裂隙网络渗流传导矩阵调整法确定自由面。通过含自由面岩体裂隙网络非线性渗流问题分析得出:岩体裂隙网络渗流的流态与裂隙网络自身性质、边界条件密切相关;如果存在非线性渗流,也并不是所有的裂隙内的渗流都是非线性渗流,而是线性渗流与非线性渗流并存;裂隙流态对裂隙渗流自由面影响很大,由于自然裂隙的水力坡降大多小于1,最后求得的岩体裂隙网络非线性渗流自由面较同条件下的线性自由面高,总体流量则较线性渗流大。渗流双重非线性问题比单重非线性问题要复杂,用传导矩阵调整法分析含自由面岩体裂隙网络非线性渗流双重非线性问题是切实可行的,而对非线性渗流分析是非常有必要的,渗流双重非线性问题分析必须建立在单重非线性问题分析的基础上。The form of free surface for the seepage in fracture network of rock mass is different from the form in continuum. Defining the free surface is a non-linear problem for seepage area, and to solve this problem the iterative methods must be used. There are a lot of seepage forms in fractures which are of non-linear fluid flow. The non-linear seepage with free surface is a dual non-linear problem, which contains the non-linear problem on seepage area and on seepage constitution, and to solve this problem the dual iterative methods must be used too. The non-linear seepage in single fracture having been analyzed, the finite element equation for the water head of nodes has been derived by using the principle of water balance. Borrowing the idea from the fixed net method to define the free surface in continuum, the whole fracture network of the study rock mass was analyzed. Then the free surface of the fracture network of rock mass can be defined by using the conductivity matrix reforming methods. Through analyzing the non-linear seepage in fracture network of rock mass with free surface, it can be found that the flow pattern in the network is determined by the characteristics of network itself and the boundary condition. If there exists non-linear seepage, that does not mean all the flow patterns in all the fractures of the network are non-linear seepage, while the linear seepage and the non-linear seepage co-exist. The seepage constitution has close relation to the free surface, as the hydraulic slope for most natural fractures is smaller than 1, the free surface for non-linear seepage of fracture network is higher than the linear seepage. The dual non-linear seepage problem is much more complex than single non-linear problem, and the conductivity matrix method to analyze non-linear seepage with free surface in network of rock mass is feasible, and the analysis for non-linear seepage in fractures is very essential, and the single non-linear seepage problem is the base of dual non-linear seepage problem even multiple n

关 键 词：自由面 岩体 裂隙网络 非线性 渗流 传导矩阵调整法 

分 类 号：TV139.14[水利工程—水力学及河流动力学]