3D岩体结构面粗糙度表征方法

Three-Dimensional Characterization Method of the Roughness of Rock Mass Discontinuities

大量的工程实践表明,岩体往往是沿着软弱结构面发生破坏的,而岩体结构面粗糙度是决定岩体结构面力学性质的重要因素。目前岩体结构面粗糙度的研究多集中于2D角度,但仅由一条剖面轮廓线来表示结构面的结构特征显然是不全面的。因此岩体结构面粗糙度表征方法应拓展到3D角度,全面地从三维曲面特征来进行评价。在参考大量文献的基础上,将二维角度的几个几何参量延伸至三维角度,提出面积扩展率S、结构面起伏度Rs,并通过平均粗糙度系数JRCS来表征三维角度的结构面粗糙度。以秭归马家沟滑坡为例,采集结构面并获取表面信息,通过统计分析和数值模拟的方法,得出三者之间的回归方程。在已知面积扩展率S、结构面起伏度Rs的基础上,可计算出平均粗糙度系数JRCs,用以判断岩体结构面在3D角度下的粗糙度大小。

Abundant engineering practices show that rock mass damage often occurs on the weak structural plane. The roughness of rock mass discontinuities is an important factor that determines the mechanical properties of the rock mass. Current researches mainly focus on two-dimensional perspective, and a single contour line is always used to represent the structural characteristics of structural plane, which is appar- ently not comprehensive and calls for a comprehensive method of three-dimensional perspective based on the features of three-dimensional plane. Based on wide literature reviews, this paper extends several two- dimensional geometric parameters into three-dimensional perspective, proposing size expansion rate （S）, structural plane fluctuation degree （Rs）, and the average roughness coefficient （JRCs） that can measure the roughness of structural plane. In the case study of Majiagou Landslide in Zigui County, the regression equations of the three parameters were obtained by the statistical analyses and numerical simulation of the information in structural plane. In conclusion, this method is applicable to characterize the roughness of rock mass discontinuities based on size expansion rate （S）, structure plane fluctuation degree （Rs） and the average roughness coefficient （JRCs）.