Filled and unfilled fracture seepage tests were conducted on 9 marble samples with different morphology surfaces by self-made rock fracture seepage test system. The effects of loading and unloading process, feeding water head, fracture surface morphology, filled sand particle size and thickness on fracture seepage under different normal stress conditions were studied. The results show that when the fracture is not filled, in the normal loading stage, the seepage flow increases linearly with the increase of feeding water head, and decreases negatively exponentially with increase of normal stress. The relationship between seepage flowrate and normal stress was obtained by embedding a 3 D morphology parameter Sq (slope root mean square). The flowrate per head increases exponentially with mechanical aperture and the average index is 3.01, thus a modified Cubic law is proposed and the modified parameters have exponential function relations with Sq of the rock fracture surfaces. In the unloading stage, the effect of normal stress on flowrate is greatly reduced and the flowrate almost keeps unchanged with the decrease of normal stress. Comparing with the unfilled marble fractures, the effects of fracture closure, fracture surface morphology and normal stress on fracture flowrate are reduced when the fracture is filled with sands. The flowrate per head increases when the filled sand size or the filled sand thickness is bigger on the whole.%利用自行研制的岩石裂隙渗流系统, 对9个不同裂隙面形貌的大理岩试样分别进行充填和未充填裂隙渗流试验, 研究了不同法向应力条件下, 加卸载过程、水头差大小、裂隙面形态、充填砂土粒径及厚度等因素对裂隙渗流的影响.试验结果表明:裂隙未充填时, 在法向加载阶段, 渗流量随水头差的增大呈线性递增, 渗流量随法向应力的增大呈负指数减小, 并得到了包含裂隙面三维形貌参数坡度均方根Sq的渗流量和法向应力关系式;单位水头流量与力学隙宽呈指数关系, 指数平均值为3.01, 基本符合立方关系.因此, 通过增加修正参数得到了修正的立方定律, 其中修正参数与裂隙面的三维形貌参数Sq呈指数关系.在法向卸载阶段, 渗流量随法向应力的降低基本不变, 相较于加载阶段, 卸载阶段法向应力对渗流量的影响明显降低;相较于未充填裂隙, 充填裂隙闭合量、裂隙面形态、法向应力在加载和卸载阶段对渗流量的影响均较小, 充填砂土的粒径或厚度越大, 相同法向应力下裂隙渗流量越大.
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