基于贴近摄影测量技术的高陡危岩体结构面调查方法

Investigation method of discontinuity in high and steep dangerous rock mass based on nap of the object photogrammetry

为解决传统危岩体结构面接触式调查手段风险高、效率低的问题,提出了一种基于无人机贴近摄影测量技术的结构面提取方法,并以某高位危岩体为例,开展了工程实例验证。首先利用多旋翼无人机对危岩体进行多角度贴近摄影,构建精细化的三维模型和三维点云;然后通过K近邻算法及PCA主成分分析完成优势结构面产状的半自动提取,最后结合三维模型中的岩体裂隙等特征,对危岩体稳定性进行快速评价。结果表明:该方法可获取符合工程精度要求的岩体点云数据,完成结构面产状的半自动提取,且倾向倾角的提取误差均在3°以内,能满足工程精度需求,为分析危岩体稳定性提供可靠的基础数据。

In this paper,a method of structural plane extraction based on UAV nap of the object photogrammetry is proposed to solve the problems of high risk and low efficiency of the traditional contact survey method of dangerous rock mass.A high level dangerous rock mass is taken as an example to carry out an engineering example verification.Firstly,a multi-rotor UAV is used to take multi-angle close photography of dangerous rock mass,and a fine three-dimensional model and three-dimensional point cloud are constructed.Then,semi-automatic extraction of dominant discontinuity occurrence is completed by K-nearest neighbor algorithm and PCA principal component analysis.Finally,the stability of dangerous rock mass is quickly evaluated by combining the characteristics of rock mass fractures in the three-dimensional model.The results show that this method can obtain rock mass point cloud data meeting the engineering accuracy requirements and complete semi-automatic extraction of discontinuity occurrence with extraction errors of dip direction and dip angle less than 3°.Therefore,this method can provide reliable basic data for analyzing the stability of dangerous rock mass.