不同采样间隔下结构面形貌特征和各向异性特征的统计参数稳定性研究

发布时间：2018-04-25 07:16

本文选题：岩石结构面 + 点云数据　；参考：《岩土力学》2017年04期

【摘要】：岩石结构面形貌特征直接影响其宏细观剪切破坏特征和剪切强度,因此,清楚地认识在不同点云数据采样间隔下结构面形貌特征和各向异性特征的统计参数稳定性,对于定量认识结构面剪切破坏机制并建立合理的抗剪强度准则十分重要。为此,借助三维白光面扫描系统对3组不同粗糙度的岩石结构面进行测量,并根据稀疏点云数据密度的原理得到其15种采样间隔的点云数据;在此基础之上,研究了2D统计参数坡度均方根Z_2、粗糙度指数R_p和θ_(max)~*/(C+1)_(2D)以及其所对应的3D坡度均方根Z_(2s)、3D粗糙度指数R_s和3D统计参数θ_(max)~*/(C+1)_(3D)随采样间隔的变化规律。研究发现,上述统计参数随着采样间隔的增大而减小,且衰减幅度逐渐增大,并与采样间隔存在二次多项式的拟合关系;同时,研究还发现,不同采样间隔下结构面的各向异性特征也具有间隔效应。为定量描述这种结构面各向异性特征的采样间隔效应,利用所构造的无量纲参数结构面各向异性系数DAC和各向异性特征参数K_α对其度量,结果表明,结构面的各向异性与间隔效应呈现正相关的关系。最后,综合岩石自然结构面分析形貌特征参数和各向异性特征参数的稳定性,在采样间隔取为0.1~0.5 mm之间表现较好的稳定性,其参数值偏差不大于3%,因此,建议一般情况下岩石自然结构面三维扫描的采样间隔可取为0.5 mm。
[Abstract]:The morphology of rock surface directly affects the macro and meso shear failure characteristics and shear strength. Therefore, the statistical parameter stability of the structural surface morphology and anisotropy characteristics under the sampling interval of cloud data at different points is clearly recognized. It is very important for the quantitative understanding of shear failure mechanism of structural plane and the establishment of reasonable shear strength criterion. Therefore, three groups of rock structure surfaces with different roughness were measured with the help of 3D white light surface scanning system, and 15 sampling interval point cloud data were obtained according to the principle of sparse point cloud data density. In this paper, the variation of the roughness index RSP and 胃 _ S / C _ 1D) and their corresponding 3D slope mean square index (R _ s) and 3D roughness index (R _ s) and 3D statistical parameter 胃 ~ (max) C _ 1C ~ (-1) D) with sampling interval have been studied by using the 2D statistical parameter, Z _ (2), the roughness index R _ (2), the roughness index R _ (2), the roughness index R ~ (2), and the 胃 _ S _ (max) / C ~ (-1) / C ~ (-1) D). It is found that the above statistical parameters decrease with the increase of the sampling interval, and the attenuation amplitude increases gradually, and there is a quadratic polynomial fitting relationship between the statistical parameters and the sampling interval. At the same time, the study also finds that, The anisotropic characteristics of the structure surface also have spacer effect at different sampling intervals. In order to quantitatively describe the sampling interval effect of the anisotropic feature of the structural plane, the anisotropy coefficient DAC and the anisotropic characteristic parameter K _ 伪 of the dimensionless parameter are used to measure the anisotropy coefficient of the structural plane. The results show that, The anisotropy of the structural plane is positively correlated with the spacer effect. Finally, considering the stability of the characteristic parameters of morphology and anisotropy of rock natural structure plane analysis, the stability of the parameters is better when the sampling interval is 0.1 ~ 0.5 mm, and the deviation of the parameters is not greater than 3. Therefore, It is suggested that the sampling interval of 3D scanning of rock natural structure surface should be 0.5 mm. in general.
【作者单位】：东北大学深部金属矿山安全开采教育部重点实验室;中国科学院武汉岩土力学研究所岩土力学与工程国家重点实验室;
【基金】：十三五国家重点研发计划(No.2016YFC0600707,No.2016YFC0801605) 国家自然科学基金(No.51379202,No.41372315)~~
【分类号】：TU45

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