岩石流固耦合实验研究刘其声.pdfVIP

第37 卷 第2 期 煤田地质与勘探 Vol. 37 No.2 2009 年4 月 COAL GEOLOGY EXPLORATION Apr. 2009 文章编号: 1001-1986(2009)02-0032-04 岩石流-固耦合实验研究 刘其声 (煤炭科学研究总院西安研究院，陕西 西安710054) : 应力与岩石的变形破坏和渗透特性关系密切。实验结果显示，一方面，岩石破坏前后其渗 透性达到最大，渗透率变化与岩石性质有关，砂岩的变化服从指数函数关系，泥质砂岩、砂质泥 岩或者泥岩服从抛物线型函数关系；另一方面，在大多数情况下，应力变化仅导致岩石微小变形 而并未破坏。渗透性随有效应力变化，并且与岩石空隙形状有关，岩石空隙形状包括三重孔隙介 质，分别为基质孔隙、裂缝孔隙和管道状孔隙。裂缝性岩心的渗透率和孔隙度损失较孔隙性岩心、 毛细管型岩石损失大，渗透率的变化总是大于孔隙度的变化。孔隙岩块的孔隙度和渗透率随有效 应力的变化关系符合指数型数学模型，裂缝型岩石宜用幂指数型数学模型描述，毛细管型岩石则 用二次抛物线数学模型描述较为恰当。 关 键 词：流-固耦合；岩石破坏；三重孔隙介质；有效应力；渗透率；孔隙度 ：P642.25; TU45 ：A Experimental study on liquid-solid coupling of rocks LIU Qisheng (Xi ′an Branch, China Coal Reaserach Institute, Xi ′an 710054, China) Abstract: The effect of stress on hydro-geological conditions or permeability of water-bearing media should follow some laws or principles. Deformed and crashed rocks induced by change of geo-stress fields provide space for groundwater storage and flow. Groundwater adjusts water-bearing space and dilatates fractures by flowing and press transferring. This is one way of coupling of liquid and solid under large deformation or rock failure. Tests show that rock permeability attains the maximum value before and after rock failure, relations of permeability and strain follow logarithmic function for brittle rocks or the quadratic parabola function for soft rocks. On the other hand, stress changing causes only small deformation and can not make rock failure in most cases. This is another way of coupling of liquid and solid. Variety of permeability with ef