复杂地质背景下露天采场边坡失稳地质灾害预测及其防治对策

露天采矿场边坡失稳作为露天开采矿山常见的一种地质灾害,对采矿工人的人身安全和矿山开采设施及财产造成了极大危害。本文通过对大宝山露天采场边坡相关影响因素的研究,从影响采场稳定性的地质因素、采空区综合分析,辅以赤平极射投影的方法,探讨了在复杂地质背景下露天采场边坡失稳地质灾害的预测及其综合治理对策。     

攀枝花露天矿排土场边坡稳定性的三维数值模拟研究

矿山排土场边坡的稳定性评价及安全管理对矿山环境的保护和地质灾害的防治具有重要意义，针对攀枝花露天矿的排土场，在建立其边坡地质模型的基础上，利用FLAC-3D软件，建立了排土场边坡的三维模型，对边坡的稳定性进行三维数值模拟研究，获得了排土场边坡变形破坏的基本特点及稳定性的基本状况，模拟的结果和现场调查的结果基本一致，从而为该排土场边坡的进一步治理提供了依据。针对FLAC-3D不能直接建立几何模型的特点，开发了一个数据前处理程序，可以自动生成与FLAC-3D相匹配的模型数据文件。     

基于地质安全评价的废弃矿山高陡边坡生态修复技术研究

新一轮找矿突破战略行动需要关注生态环境保护,废弃露天矿山生态修复则是矿地综合利用、生态环境保护的重要举措,其中高陡边坡修复是废弃矿山生态修复的重点与难点。为此,选择浙江省兰溪市灵洞乡洞源村废弃露天矿山开展了生态修复技术示范研究,在实地勘察、工程地质测绘与工程钻探的基础上,基于有限元方法,对边坡进行安全性数值分析,进而对高陡边坡实施生态修复。数值分析表明：边坡随着降雨的进行,其安全系数从1.458降至0.851,存在安全隐患;高陡边坡生态修复必须辅以削坡降低斜坡坡度、在边坡前缘实施挡土墙等工程手段才能达到安全性要求;合理排水可大大降低水对边坡安全性的影响,增强边坡的稳定性。经过生态修复设计后,暴雨条件下边坡安全系数显著提高且基本保持在1.7左右,达到了安全性的设计要求。该技术示范可为其他废弃矿山生态修复提供参考。     

基于无人机摄影测量的露天矿边坡数值模拟

数值模拟是露天矿山边坡稳定性分析的常用方法,边坡模型构建是数值模拟的基础,地形测量的准确性对于边坡稳定性分析精度具有十分重要的影响。近年来,低空低速小型无人机(UAV)被广泛应用于地质调查中,为复杂条件下地形快速测量提供了一种可行的方法。针对露天矿山边坡坡形更新快、地形复杂、人工测量困难的情况,采用搭载单镜头小型无人机,对露天矿山边坡进行低空摄影测量,并通过飞行试验,对比研究了无人机搭载镜头旋转角度对边坡测量精度的影响,最终得到高精度边坡数字高程模型(DEM),并通过Surfer、Rhino等软件转化为三维FLAC模型,实现从无人机测量到三维数值模型的快速建立。得到以下可供参考的研究结论:在目标边坡坡度小于45°时,无人机搭载镜头旋转角度不同对边坡测量精度有较大影响,当镜头旋转角度介于70°~90°时,获得的测量精度较高;与人工测量相比,无人机摄影测量获得的边坡坡形更符合真实边坡实际坡型;无人机航拍照片经过PhotoScan、Surfer、Rhino等软件的转化,能够快速建立三维数值模型,并获得更好的数值模拟计算结果,满足边坡稳定性分析需要。     

多级框架锚索与微型抗滑桩群组合加固边坡技术

我国既有露天矿山边坡失稳情况绝大多数发生在台阶边坡或组合台阶边坡,本文针对露天矿山组合台阶边坡的特点提出一种以预应力框架锚索和微型抗滑桩群作为主要支挡结构的边坡加固方案。以洛钼集团三道庄露天矿观礼台下部滑坡为例,在简要分析其成因及整体稳定性的基础上详细介绍该方案的主要实施过程及关键施工技术,并对施工过程监测结果进行分析。结果表明:边坡治理前整体处于基本稳定状态,但随着暴雨、地下水的影响,边坡稳定性将不断降低,最终会发生整体失稳;治理及监测结果表明该方案可行且有效,随着施工过程的结束,边坡变形逐渐稳定并趋于停止,至今边坡状态良好。     

地下矿体采动下的露天采场边坡稳定性研究

对于进入中晚期的露天金属矿,为了延长矿山的寿命或露天转地采稳产过渡,通常选择露天与地下联合开采,那么矿体采动下的边坡稳定性问题则尤为突出。在边坡几何形态、上部荷载和材料性质等不变的情况下,极限平衡获得的边坡安全系数为定值,因此,不能用来反映地下矿体采动对边坡稳定性影响。为了克服常规极限平衡方法的上述缺陷,采用基于边坡应力场的矢量和法求解滑动面的安全系数,结合蚁群算法与遗传算法联合搜索边坡临界滑动面,以确定矿体开采前后边坡的安全系数和临界滑动面。最后,给出一个假定算例和两个工程算例说明上述安全系数求解和临界滑面搜索方法的有效性,并揭示了地下矿体开采对露天采场边坡的稳定性的影响。     

模糊评判在露天转地下矿山的矿房结构参数优化中的应用

模糊评判法能较好地解决方案选择的问题。本文针对石人沟铁矿露天转地下矿山过渡期开采期间,矿山地下开采带来的露天边坡、地下采场稳定性问题,通过数值模拟,得到地下第一中段开采时地下采场和边坡的应力、应变数值,并结合矿块的采切比、矿块回采率经济指标,运用模糊数学的方法,建立了考虑经济效益的稳定性模糊评判模型。通过合理确定评价指标的隶属度函数和利用二元排序法构造判断矩阵确定各评价指标的权重,对9种方案进行了综合评判,确定了最优方案,选出了合理的矿房结构参数,既可保证矿山的安全生产,又可保证矿山经济效益。     

大型露天矿山不稳定边坡治理初探

本文介绍了我国大型露天矿山边坡现状及以监测为先导进行稳定性评价和分期实施应急加固和永久性综合治理的系统工程方法。还总结了产生滑坡的影响因素和滑体边界探测技术及滑坡综合治理措施。     

矿山地质环境影响评价及修复研究——以汶川某废弃露天矿山为例

矿山正常的生产经营活动势必形成一定的矿山地质环境问题。为全面贯彻生态文明思想,牢固树立“绿水青山就是金山银山”的理念,按照恢复生态、兼顾景观总体要求,因地制宜、多措并举,扎实开展废弃露天矿山地质环境修复。依据矿山地质环境保护与恢复的相关规范与要求,以汶川某废弃露天矿山为例,从矿山环境角度介绍了矿山地质环境的影响因素,开展矿山斜坡整体稳定性、采场边坡稳定性、弃渣堆稳定性及地形地貌景观破坏等地质环境影响评价,划分治理重点、次重点和一般3个基本的矿山地质环境保护与恢复防治区。结果表明: 矿山斜坡及弃渣堆现状基本稳定、采场边坡稳定性较差、地形地貌景观影响和破坏程度中等; 研究区矿山地质环境保护与恢复治理可划分为一般防治区和较严重防治区,其中一般防治区面积约554 m²(矿区无因采矿活动诱发的地质灾害,影响区内无居民居住,无威胁对象,矿区及周围地表水体未漏失,矿业活动对水土环境影响程度为影响程度小,未影响到矿区及周围生活供水)、较严重防治区面积186 m²(矿区与影响区地质灾害发生可能性小,地形地貌景观影响和破坏程度较严重)。针对评价结果提出的“坡面浮石清理+清除建筑垃圾、块石+植被重建”等修复建议,为同类型矿山绿色开采及地质环境保护措施提供了的重要技术参考依据。     

某露天矿岩质开挖边坡岩体力学参数获取及开挖稳定性分析

如何可靠的获取岩体的力学参数,一直是岩体力学界研究的重要课题。本文采用RMR分类方法、Hoek-Brown强度准则,获得了边坡稳定性计算分析所用的摩尔库伦模型基本参数,实现了室内岩石力学实验参数与野外现场实际岩体参数的过渡与衔接。并以某露天矿岩质开挖边坡典型剖面为例,进行该边坡岩体力学获取及开挖稳定性分析,计算结果表明:对于所计算的剖面边坡,应注意对露天采矿坑底、边坡坡脚处进行有针对性的治理工程,以保障矿山的安全生产。     

咸阳北塬边垃圾土边坡稳定性分析

目的垃圾土边坡作为建筑边坡的治理和利用存在不少难点。以咸阳北塬边垃圾土边坡为例,详细分析了垃圾土稳定性影响因素。方法结合该垃圾土（建筑垃圾和生活垃圾）的物质成分及结构特性,在现场静力触探试验、反算及专家经验等综合分析的基础上,确定了垃圾土的抗剪强度参数。结果采用极限平衡法计算出该垃圾边坡稳定性系数,该稳定性系数与目前该边坡的实际状况基本一致。结论提出了垃圾土边坡稳定性分析方法和失稳后的治理方案,它对下部建筑群的抗滑建设具有重要的指导意义。     

斜坡系统可靠性分析研究

:斜坡系统是一个多变的、随机的、具有多种不确定性的复杂系统 ,因此在斜坡稳定性研究中引入可靠性理论意义重大且应用前景广阔。文中从单体斜坡系统和区域斜坡系统两个方面 ,论述了斜坡系统可靠性分析的研究现状和发展趋势。单体斜坡系统可靠性研究的主要方向是 :影响因素与评价模型的进一步研究 ,初步建立可靠指标与安全系数相结合的斜坡稳定性二元指标体系。区域斜坡系统可靠性研究的主要方向是 :利用具有普适意义的可靠性指标 ,结合地理信息系统 (GIS)进行斜坡稳定性研究 ,初步建立风险评价和风险管理的斜坡安全体系     

卡基娃滑坡的形成机制和稳定性浅析

卡基娃滑坡位于木里河卡基娃水电站拟建坝址下游左岸,为一特大型基岩古滑坡,其稳定性关系到建坝、建库的可行性和安全性。通过勘察,掌握了滑坡的边界条件、变形特征和形成机制;结合河谷地貌史的研究,采用宏观分析和定量计算相结合的方法对滑坡稳定性进行了评价,为下一步工作奠定了基础。该滑坡是川西高山峡谷区弯曲-拉裂型滑坡的典型代表,通过其形成机制和稳定性的研究,对今后认识和研究该类型的滑坡有一定帮助。     

新形势下地勘单位档案管理工作的思考

阐述了地勘单位档案管理工作的意义,指出了新形势下地勘单位档案管理工作存在的具体问题,提出了改进和加强地勘单位档案管理工作的建议。     

规范农村集体建设用地使用权流转的法律思考

介绍了完善农村集体建设用地使用权流转的相关制度,对其流转模式进行了有益探讨;提出在农村集体建设用地使用权流转中必须规范操作规程,并且还要建立一套合理地收益分配机制,使之既能体现国家、集体和个人的合法利益,又能充分保障农民的权益,保证农村经济持续、稳定、健康发展。     

广东省大埔县赤羌坪滑坡稳定性评价及防治对策

由于赤羌坪地质环境条件及不利气象因素影响,致使古滑坡复活,直接威胁当地群众生命财产及道路交通安全。本文在滑坡地质灾害勘查的基础上,分析了影响滑坡稳定性的因素,采用剩余推力传递法进行滑坡稳定性定量评价,得出:天然状态下,滑坡处于不稳定状态,在持续降雨及强降雨作用下,稳定程度进一步降低,随时有大规模滑动破坏的危险。为此,提出了"排水+锚索抗滑桩支挡"工程治理方案对滑坡进行工程治理。     

Construction,management and maintenance of embankments used for road and rail infrastructure: implications of weather induced pore water pressures

Understanding the age and construction quality of embankments used for road and rail infrastructure is critical in the effective management and maintenance of our transport networks, worth £billions to the UK economy. This paper presents for the first time results from full-scale, carefully controlled experiments on a unique model embankment conducted over the 4-year period between 2008 and 2011. It combines point location and spatially distributed measurements of pore water pressures and water content with outputs from hydrological modelling to draw conclusions of significance to both ongoing research in this field and to the asset management practices of infrastructure owners. For researchers, the paper highlights the crucial importance of transient permeability and soil water retention behaviour of fill materials in controlling the magnitude and distribution of pore water pressure in response to climate and weather events. For practitioners, the work demonstrates that there are significant differences in pore water pressure behaviour across the embankment, which is influenced by construction-related issues such as compaction level, aspect and presence of a granular capping material. Permeability was also observed to vary across the embankment both spatially and with depth, being dependent on degree of saturation and macroscale effects, particularly within a ‘near surface zone’. It is proposed that this ‘near surface zone’ has a critical effect on embankment stability and should be the focus of both ongoing scientific research and inspection and monitoring as encompassed by asset management regimes.     

Sensitivity Analysis of Coal Rib Stability for Internal Mine Dump in Opencast Mine by Finite Element Modelling

The present paper discusses the impact of the geometrical parameters of the coal rib and the mine dump on the stability of the coal rib. The geometrical parameters such as the slope angle, the height of dragline dump, the height of main dump, the gradient of seam and the thickness of coal rib have been considered as input to the numerical model for the stability analysis of the coal rib. Sensitivity analysis has been performed based on the results of the analysis in term of factor of safety of the coal rib. The input parameters have been classified in terms of significance (i.e. very high significance, high significance medium significance and low significance). The factor of safety is more influenced by highly significant parameters. The height and the slope angle of dragline dump and the thickness of the coal rib are highly significant parameters for the stability of the coal rib. The gradient of the seam is a medium significant parameter whereas, height of main dump and the number of dragline cut dump are low significant parameters for stability of coal rib.     

The Holocene history of highland pine forests in a submediterranean mountain: the case of Gredos mountain range (Iberian Central range,Spain)

The significance of Pinus sylvestris and Pinus nigra forests in Gredos mountain range in the Iberian botanical literature has been traditionally a matter of controversy. Considered for many botanists to be anthropogenic forests, a high amount of syntaxonomic approaches, cartographies of potential vegetation and dynamic models have been created based on this guesswork.Nevertheless, this work contributes new data that contradicts this previous hypothesis. For the first time, these data prove the existence of a bioclimatic belt where pine trees dominated during the last 6500 years, clarifying its altitudinal range, surface extension, and its stability. The study is based on the analysis of fossil macrorests and megarests, dated using radiocarbon. The results obtained cohere with the suggestions of other authors that assume the native character of P. nigra and P. sylvestris in this area, based on data of diverse origin (palynological, historical, toponymical, dendrochronological or geobotanical).The paper then continues to discuss the geobotanical interpretation of the results and the regional lines of management, as well as the potential causes that could have induced the marked decline of pine forests in the last millennia.     

Effects of hydraulic conductivity/strength anisotropy on the stability of stratified,poorly cemented rock slopes

This paper presents a numerical procedure to explore how hydraulic conductivity anisotropy and strength anisotropy affect the stability of stratified, poorly cemented rock slopes. The results provide information about the anisotropic characteristics of the medium, including the orientation of bedding planes, the anisotropic ratios of the hydraulic conductivity and the geological significance of the hydraulic conductivity anisotropy on the pore water pressure (PWP) estimation of finite slopes. Neglecting the hydraulic conductivity anisotropy of a slope with horizontal layers leads to a 40% overestimation of the safety factor. For a dip slope with inclined layers with θ = 30°, including the strength anisotropy caused a 25% reduction of the safety factor compared to the cases which isotropic strength is assumed. This paper highlights the importance of the hydraulic-conductivity anisotropy and the strength anisotropy on the stability of stratified, poorly cemented rock slopes.