基于岩体质量评价与分区的露天矿岩质边坡生态重建技术

露天矿岩质边坡生态恢复与重建是绿色矿山建设的重要组成部分,开展露天矿岩质边坡生态重建技术研究,对于实现我国绿色矿山建设具有重要的推动作用,岩质边坡极端恶劣的立地条件制约了该项工作的顺利开展。以研山铁矿东帮边坡为研究对象,在详细分析该边坡地层分布特征、岩性、结构面产状及风化程度的基础上,采用三维激光扫描技术,构建东帮边坡DTM模型,在三维激光扫描结果与地质平面图对比分析的基础上,将东帮边坡划分为北、中、南3个区域;根据岩石力学试验结果,结合各区域岩体结构面空间几何信息,采用BQ分类法对上述各区域岩体质量进行评价,结果为:北、中、南区岩体质量等级分别为Ⅳ级、III级和II级,以矿区公路为同区上、下半区的分界线,下半区岩体质量好于上半区;根据边坡岩体质量分级结果,在不同区域采用与该区域岩体质量等级及节理、裂隙发育情况相适应的生态重建方案,其中,北区上、下半区分别采用客土喷播技术和厚层基材喷播技术,且下半区喷播基材中的黏结剂和团粒剂含量高于上半区,中区上、下半区均采用以铁尾矿为基质的人工土壤喷播技术,南区上、下半区均采用爆破燕窝、植生孔与高保水绿化喷播相结合的岩质边坡生态重建技术方案;边坡平台在前期采用林地、草地相结合的生态重建技术,待平台上土壤熟化后,采用林地、中药种植地相结合的生态重建技术;根据边坡最终境界与新河的相对位置关系,采用疏干排水的方式降低地下水对边坡稳定性影响的同时,设计了边坡生态重建所需的滴灌系统。研究成果为露天矿岩质边坡生态重建技术方案选取提供了新思路。

Ecological reconstruction technology of rock slope in open pit based on rock mass quality evaluation and division

Ecological restoration and reconstruction of rock slope in open pit is an important part of green mine construction.Research on the ecological reconstruction technology of rock slope in open pit plays an important role in promoting green mine construction in China.Nevertheless,the extremely harsh geological conditions of rock slope restrict the smooth development of ecological restoration.In this paper,the authors investigated the eastern slope of Yanshan Iron Mine.Based on the detailed analysis of stratum distribution,lithology,structural plane occurrence and weathering degree of the slope,the DTM model of eastern slope was constructed using three dimensional laser scanning technology.Comparing and analyzing the results of three dimensional laser scanning with the geological plane map,the eastern slope was divided into three regions:north,middle and south.According to rock mechanic test results,combined the spatial geometric information of structural planes in different regions,the BQ classification method was used to evaluate the rock mass quality in above regions.The results show that the rock mass quality grades in the north,middle and south regions are grade IV,III and II,respectively.Taking the highway in the mining area as the dividing line between the upper and lower half of the same region,the rock mass quality in the lower half is better than that in the upper half.Different ecological reconstruction plans,according to the grading results of the slope,were adopted to corresponding regions.More specifically,the technology of soil spraying and thick base material spraying were adopted in the upper and lower half of the northern region,respectively;artificial soil spraying technology based on iron tailings was adopted in the upper and lower half of middle region;and the technological scheme of ecological reconstruction of rock slope combining blasted bird’s nest,planting hole and high water conservation green spraying was adopted in upper and lower half of southern region.The ecological reconstruction technology of forest land and grassland was adopted in the early stage,while the ecological reconstruction technology combining forest land with traditional Chinese medicine planting land was adopted after soil ripening on the platform.Based on the relationship between the final boundary of slope and the relative position of Xinhe River,the drip irrigation system for slope ecological reconstruction was designed to satisfy the need of ecological reconstruction,meanwhile,sewer drainage was used to reduce the influence of groundwater on slope stability.The research results provide a new idea for the selection of ecological reconstruction technology scheme of rock slope in open pits.