基于无人机航测技术的露天矿山爆堆形态分析

露天矿山爆堆形态是爆破效果评价的重要组成部分。为了精准高效地评价台阶爆破的爆堆形态,明确相应的评价指标,采用了灵活性好的低空多旋翼小型无人机航测技术。以大宝山露天多金属矿山铁门661 m平台爆区为例,根据采场空间布局及精度要求,设置相对航高为100 m,五向航摄模式下的旁向和航向重叠率均为80%,爆区周边布设了4个像控点,采用Smart3D软件生成了台阶爆前爆后两期的三维可视化实景模型。三维模型误差较小,像控点高程中值误差为2.79 cm,均满足航测精度要求。通过IData软件进行点云和高程信息提取,得到了爆堆空间分布形态及尺寸参数,爆区拉裂范围较大且表面块度分区现象明显,认为与孔网参数设计、地质条件等有关。工程实践表明:无人机航测在爆堆形态分析方面具备一定的可行性,为台阶爆破效果分析提供了新思路。

Analysis of Muckpile Shape in Open-pit Mine Based on UAV Aerial Survey Technique

Muckpile shape of open-pit mine is an important part of blasting effect evaluation. In order to accurately and efficiently evaluate,the corresponding evaluation index is defined,and the low altitude multi rotor small UAV aerial survey technology with good flexibility is adopted. Taking the blasting area of Tiemen 661 m platform in Dabaoshan Open-pit Polymetallic Mine as an example,according to the spatial layout and accuracy requirements of the stope,the relative heading height is set as 100 m,the side and heading overlap rate is 80% under the five direction aerial photography mode,and four image control points are set around,generate the three-dimensional visual real scene model of two stages before and after the bench blasting by Smart3D software. The error of 3D model and image control point elevation is small and 2. 79 cm respectively,which meets the requirements of aerial survey accuracy. Through the extraction of point cloud and elevation information by IData software,the spacial distribution shape and size parameters of muckpile are obtained. The cracking range of blasting area is large and the partition phenomenon of surface fragmentation is obvious. It is considered that the phenomenon is related to the design of hole network parameters and geological conditions. The engineering practice shows that the UAV aerial survey has certain feasibility in the analysis of muckpile shape,which provides a new idea for the analysis of bench blasting effect.