节理在不同接触状态下的渗流特性  

FLOW CHARACTERISTICS OF JOINTS UNDER DIFFERENT CONTACT CONDITIONS

作　　者：夏才初[1,2] 王伟[1,2,3] 曹诗定[1,2,4] 

机构地区：[1]同济大学岩土及地下工程教育部重点实验室,上海200092 [2]V同济大学地下建筑与工程系,上海200092 [3]闵行区建设工程安全质量监督站,上海201100 [4]上海市政工程设计研究总院,上海200092

出　　处：《岩石力学与工程学报》2010年第7期1297-1306,共10页Chinese Journal of Rock Mechanics and Engineering

基　　金：国家自然科学基金资助项目(40472142,50579088)

摘　　要：将取自雅砻江水电站锦屏二期工程施工现场的白色大理岩,采用劈裂法制成张拉性人工节理试件,用TJXW–3D型岩石节理表面形貌仪测量节理的表面形貌,并采用自行编制的表面形貌和组合形貌参数计算软件,分析其用以表征节理表面形貌的节理面二维分形维数,以及用以表征组合形貌的节理内空腔的三维分形维数。对节理面进行错位,以改变其接触状态,然后进行不同接触状态下节理的渗流试验。将试验实测结果与传统的经验公式及各种修正公式的计算值进行比较,发现利用现有经验公式分析试验结果存在较大的偏差。通过对实测数据做进一步分析,发现表征节理表面形貌和组合形貌特征的分形维数也是影响节理渗透率的重要因素之一。综合考虑节理透过率以及表征节理形貌的分形维数等因素对节理渗透特性的影响,得到更为合理的节理渗流经验公式,该公式具有更广阔的应用前景。Seepage characteristics of rock joints under different contact conditions are studied.Artificial tension rock joints are made of white marble samples taken from construction site of the Yalong River（Jinping II Project）,using cleaving method.Surface topographies of rock joints are measured by a three-dimensional TJXW-3D-typed portable rock surface topography measuring instrument.A self-programmed software is used to calculate parameters for rock joints,including not only 2D fractal dimension of surface topography for each single joint surface,but also 3D fractal dimension of composed topography for vacuum formed by two coupled joint surfaces.Then seepage experiments of the artificial rock joints are carried out.During the experiment,contact condition of rock joints varied by offsetting the relative position of the joints from 1 mm to 6.5 mm.Deficiency of traditional empirical formulas,such as Darcy′s law,cubic flow law and its modified formula,and seepage formula in turbulent flow,are exposed by comparing experimental results with calculating ones from those traditional empirical formulas.After a thorough study of experimental results,it is discovered that fractal dimensions of single joint surface topography and composed joint topography have great influences on the seepage characteristics of rock joint.By taking permeability and the topography coefficients of rock joint into consideration,a new empirical formula for seepage in rock joints that highly matches the test results is presented,which is much more reasonable in theory and accurate in practice than traditional formulas.

关 键 词：岩石力学 表面形貌 组合形貌 节理 接触状态 错位 渗流 分形 

分 类 号：TU45[建筑科学—岩土工程]