岩体结构面面密度统计及体密度优化

2D Density of Discontinuity Statistics and Optimization of Volumetric Discontinuity Density

为了给岩体稳定性分析和渗透性评价提供更加可靠的数据,提出了基于差分进化算法拟合实测面密度从而优化结构面体密度的三维结构面网络模型建模方法。采用RTK-GPS数字化量测技术,研究了结构面迹线3D数字化模型及数字化测窗建立方法;引入“地形化”的圆形测窗,提出扩展为地形化曲面正方形连续布置测窗,分析了圆形取样窗大小对密度估计的影响,比较了正方形测窗和圆形测窗估算结果。以甘肃北山地面花岗岩结构面量测数据为例,应用该方法。研究表明,优化的体密度能高度拟合各分块实测面密度,由此建立的3D结构面网络模型更符合实际结构面分布规律。

In order to provide more reliable basic data for the stability analysis and evaluation of permeability of rock masses in Beishan area,a modeling approach of 3D discrete discontinuity network considering optimization of the volumetric discontinuity densities was developed by fitting 2D continuous measured discontinuity trace densities used differential evolution algorithm.RTK-GPS digital measurement technology was used to study the 3D digital discontinuity trace model and the establishment of digital sampling windows.A“topographic”circular window were introduced and expanded to“topographic”continuous arranging quadratic windows.The affect of sizes of circular sampling windows on results of density estimation was investigated.The values of density estimation using circular and quadratic sampling windows were compared.The method were applied to measurement data of ground granite discontinuity in Beishan,Gansu Province.The results show that the optimized volumetric discontinuity density can highly fit 2D density of discontinuity of each block,and the 3D discrete discontinuity network model thus established is more consistent with the actual distribution of discontinuity.