表面形貌对岩石摩擦滑动本构参数影响研究

对典型岩石摩擦滑动试验装置进行改进，以千枚岩、石英岩、石英砂岩、岩屑砂岩、大理岩、石灰岩、鲕状石灰岩和白云质灰岩等岩样作为研究对象，以其抛光面作为摩擦滑动面，从本构参数的角度出发，研究自然、饱水和干燥状态下岩石摩擦滑动过程中的稳定性。采用R-D本构模型分析不同状态下岩石的摩擦滑动本构参数，基于岩石抛光表面形貌分析微凸体和分形维数对岩石摩擦滑动本构参数的影响。试验结果表明：在相同抛光条件下，不同岩石滑动表面微凸体的直径均值、高度均值和表面轮廓平均高度不同，随着这3个参数的增加，本构参数均呈线性规律降低；滑动表面形貌越精细分形维数越大，随着分形维数的增加，本构参数呈线性规律增加。

INFLUENCE OF SURFACE TOPOGRAPHY ON CONSTITUTIVE PARAMETER OF ROCK FRICTIONAL SLIDING

The typical test apparatus of rock friction sliding was designed and improved. The samples including phyllite，quartzite，quartz sandstone，lithic sandstone，marble，limestone，lite limestone and dolomitic limestone were studied experimentally using the apparatus. The polished surfaces of the samples were taken as the frictional sliding surfaces. The force-displacement curves of frictional sliding for the samples were investigated experimentally under the natural state，saturated state and dry state. The frictional sliding constitutive parameters were analyzed according to Ruina-Dieterich(R-D) constitutive model；and the influence of the asperities and fractal dimensions of polished surfaces for the samples on the constitutive parameter was analyzed. The test results reveal that the three parameters which are the mean diameter of the asperity，the mean height of the asperity and the mean height of the surface profile are different for different rocks under the same polishing condition. As for the mean diameter of the asperity，the mean height of the asperity and the mean height of the surface profile increase，the constitutive parameters are decreased with the linear law. The surface topography of the sliding surface finer，fractal dimension is larger. The constitutive parameters are increased with the linear law as fractal dimension increases.