裂隙岩体渗透张量的对称性证明及主渗透性推导

裂隙岩体具有显著的各向异性和非均质性的特点,研究时主要分为等效非连续介质模型、等效连续介质模型和孔隙–裂隙双重连续介质模型3种情况考虑。岩体渗流参数是岩体渗透特性的量化形式,是连续介质模型求解裂隙岩体渗流场的基础。基于裂隙岩体的性质及工程设计方面的考虑,经常把裂隙岩体当作各向异性的多孔连续介质来处理,而渗透张量的对称性是连续介质的标志。各类教科书缺乏渗透张量的对称性证明,而是直接使用这一结论。,为更加深入地理解裂隙岩体渗透张量的本质,证明含有单个裂隙、单组裂隙或多组裂隙的裂隙岩体的渗透张量的对称性,阐明渗透张量的主轴与主渗透性以及水力梯度与渗透流速的关系,进而推导出渗流控制方程。

SYMMETRY CERTIFICATION OF PERMEABILITY TENSOR AND DERIVATION OF PRINCIPAL PERMEABILITY OF FRACTURED ROCK MASS

Fractured rock mass has obvious anisotropic feature,which is often treated as equivalent discontinuous medium,equivalent continuous medium or doubling continuous medium of pore-fissure.The seepage parameters of rock mass are quantized form of permeability,and also are the basis to solve seepage field of continuous medium.Based on the attribute of fractured rock mass and by taking engineering design into account,fractured rock mass is often considered to be anisotropic continuous medium,and the symmetry of permeability tensor is the symbol of continuous medium.Every type of textbook lacks of the symmetry certification,but uses the conclusion directly.For the sake of comprehending the essence of the permeability tensor further,the symmetry of the permeability tensor of fractured rock mass with single fissure,single set of fissure or multiunit fissure is proved to illuminate the relationship between percolation gradient and the permeating flow rate,and then the dominating equation of seepage flow is derived.