利用TLS技术测定闭合节理直剪试验剪切面面积  

Determination of shear area in closed joint direct shear test using TLS technique

作　　者：杨荣华[1] 万震[1] 谢强[1] 曹志林 杨文君 YANG Ronghua;WAN Zhen;XIE Qiang;CAO Zhilin;YANG Wenjun(School of Civil Engineering, Chongqing University, Chongqing 400045, China;Institute of Rock Instability and Seismicity Research, Dalian University of Technology, Dalian 116024, China)

机构地区：[1]重庆大学土木工程学院,重庆400045 [2]大连理工大学岩石破裂与失稳研究中心,辽宁大连116024

出　　处：《西安建筑科技大学学报（自然科学版）》2019年第1期46-50,共5页Journal of Xi'an University of Architecture & Technology(Natural Science Edition)

基　　金：国家自然科学基金(51008319);中央高校基本科研业务费(CDJZRPY14200001)

摘　　要：针对现行直剪试验中未考虑剪切面"闭合不规则空间曲面"特性对剪切面面积测定的影响,提出了一种基于地面三维激光扫描(Terrestrial Laser Scanning,TLS)技术的闭合节理直剪试验剪切面面积测定方法.该方法首先通过三维激光扫描仪获取岩石试样的三维点云数据,然后进行点云去噪和提取岩石剪切面轮廓点云数据,接着由剪切面轮廓点云数据拟合最佳投影面,计算轮廓点云在投影面上的投影点集及其各点投影坐标,最后利用逐点插入的Delaunay三角剖分算法获得轮廓点云投影点集的凸包,凸包三角形面积和即为剪切面的面积.实验结果表明:基于TLS的闭合节理直剪试验剪切面面积测定方法操作简单,且面积计算精度高,适用于任意形状闭合节理面的剪切面面积计算.According to the fact that the effect of closed irregular space surface on shear area determination is not considered in current shear test,a determination method of shear area in closed joint direct shear test based on Terrestrial Laser Scanning(TLS)technique is proposed.In this study,the three dimensional(3D)point cloud data of rock samples are obtained using a 3D laser scanner,and then the point cloud data of rock shear surface contour are extracted from denoised data and used to fit the best projection plane.Furthermore,the set of projection points and projection coordinates of each point in point cloud of contour on projection plane are calculated.Finally,the incremental insertion algorithm of Delaunay triangulation is adopted to determine the convex hull composed by the projection point set,and the sum of the area of triangle in convex hull is the shear area.The experimental results show that the TSL-based determination method of shear area in closed joint direct shear test is simple for operation,and the high accuracy of area calculation is suitable for the determination of shear area in closed joint surface with arbitrary shape.

关 键 词：直剪试验 闭合节理 剪切面 面积测定 地面激光扫描 点云 

分 类 号：TU455[建筑科学—岩土工程] P237[建筑科学—土工工程]