挂帮矿充填法开采对高陡边坡及采场围岩稳定性的影响

以大冶铁矿高陡边坡下2#挂帮矿回采为工程背景,首先采用GEO-SLOPE软件对挂帮矿开采中边坡稳定性进行了分析;然后通过现场监测及模型相似实验相结合的手段,研究矿柱及围岩的应力及位移变化规律,探讨了挂帮矿充填法开采对采场围岩稳定性的影响.研究表明挂帮矿所在露天初始边坡经过扩帮及内部开采后,安全系数平均值由1.274下降至1.005,边坡稳定性较差;目前空区采场矿柱及围岩稳定性较好,但必须对现有采空区进行充填,改变空区及矿柱应力集中状态,才能进行矿柱及顶底板矿石回采.      

基于FLAC~(3D)数值模拟的某钨矿缓倾斜矿体采场矿柱稳定性研究

针对采用全面采矿法的矿山,其采场矿柱的位置与尺寸留设一直是矿山安全高效生产关注的问题。通过对某钨矿缓倾斜矿脉采场回采过程中的矿柱留设进行数值模拟研究,采用FLAC3D三维有限元数值模拟软件建立采空区、围岩单元模型。根据采场周围应力、应变的计算结果显示,整个采空区顶板沉降均匀,顶板围岩位移呈拱形分布,开挖区间中部位移值略大于两侧,采场布置3排矿柱可以保障整个采空区的稳定性,为矿山采场开挖及采空区稳定提供科学依据。     

某矿复杂采空区稳定性模拟分析

随着计算机技术的发展,多种监测、探测工具和数据分析软件的组合应用是矿山数字化平台建设方向,也是地下矿山采空区稳定性分析的重要手段。以安徽某矿山的-760 m13#R采场开采为背景,采用C-ALS、FLAC~(3D)、Surpac三种软件对矿体回采后进行稳定性分析评价。可知采场回采结束后,由于矿体的回采使顶板失去支撑导致顶板及空区周围围岩均产生指向空区的位移移动,采空区的顶底板及侧帮围岩处于拉应力状态,空区的下盘围岩受到较大的拉应力超过围岩的抗拉强度,建议加强监测。虽采空区总体稳定,但也需及早充填与加强监测。其分析结果符合实际情况,为矿山的生产安全和充填工作提供合理有效的依据。     

昭通铅锌矿采空区稳定性的FLAC^3D数值模拟研究

昭通铅锌矿古采空区体积达60多万m3,且形态复杂.由于古采空区未得到处理和矿区民采泛滥,Ⅰ号矿带主矿体古采空区多次发生垮塌,并引发地表塌陷、山体开裂和井下采场垮塌等现象.本文采用FLAC3D快速拉格朗日差分分析方法,对采空区稳定性进行了数值模拟,以便对采空区处理方案提供理论依据.模拟结果表明,采空区顶板发生向下位移,围岩位移剧烈,引起地表变形大;采空区顶板处出现明显的竖直应力集中和水平应力集中,而采空区周围塑性区可延伸至地表.     

基于协同回采的深部厚大矿体分段充填采矿法

针对预控顶分段充填法在深部开采存在的预控顶巷道掘进工序繁杂、顶板易受爆破震动影响等缺点,本文提出垂直孔与水平孔协同回采的机械化分段充填采矿法(协同回采分段充填法).该方法通过改变顶板支护工序的顺序,将预控顶变为后压顶,能够有效地解决顶板围岩稳定性问题.进而对协同回采分段充填法进行优化研究:一方面,通过SURPAC到ANSYS的模型转换技术,进行采场稳定性数值分析,获得最佳的结构参数;另一方面,通过分区出矿分区支护的方式,解决两帮支护不到位和出矿效率低的问题.将该方法应用于新城金矿V#矿体开采,结果显示顶板岩移量显著减小,且各项经济技术指标均得到改善,实现了高应力条件下厚大矿体的安全高效开采.      

持续暴雨作用下排土场层状碎石土边坡稳定性

为了研究排土场层状碎石土边坡在持续暴雨条件下的入渗过程及稳定性,推导了土体天然含水率、天然重度与天然体积含水量的换算公式,作为快速确定边坡土体初始基质吸力分布的依据.建立算例排土场有限元分析模型,进行降雨条件下饱和-非饱和渗流、孔压-应力耦合以及边坡稳定分析.结果表明:持续暴雨作用下排土场会在透水性最强的边坡浅层形成集中渗流通道,当坡底存在弱透水性土层时会切断渗流通道,导致雨水从坡脚涌出;排土场边坡位移在降雨期间不断增长,但增长速度越来越慢,雨后边坡位移立即开始减小;降雨初期边坡稳定性系数下降较快,边坡浅层渗流稳定后基本保持不变,雨后缓慢增大.排土场层状碎石土边坡在持续暴雨作用下容易在降雨中后期失稳.      

慈林山煤矿近距离采空区下巷道围岩控制技术研究

针对慈林山煤矿9107工作面近距离采空区下回采巷道稳定性较差、顶板易冒落等问题,结合9107工作面的工程地质条件,采用数值模拟的方法,确定了8号煤层和9号煤层近距离采空区回采巷道内错10～20 m的合理距离。现场监测结果表明,巷道围岩变形在10 d后趋于稳定,顶板最大沉降量约为88 mm,底板最大底鼓量约为23 mm,两帮最大移近量为185 mm,围岩稳定性得到有效控制。     

高应力下顶板充填体破断机理与试验研究

下向分层进路尾砂胶结充填采矿法顶板为胶结充填体,深部高应力下回采,顶板的稳定性直接关系到整个回采过程的安全.判别顶板的稳定性是安全回采的前提条件.通过理论分析并结合数值模拟、相似模拟等试验手段判别了顶板充填体的破坏机理,提出了充填体破坏形式及预防顶板破坏的合理布筋方式,确保了回采过程的安全.     

合理布筋方式提高顶板充填体稳定性试验研究

下向分层进路式尾砂胶结充填采矿法顶板为胶结充填体,深部回采,顶板的稳定性直接关系到整个回采过程的安全.在充填体中布置钢筋可提高顶板自身的稳定性.通过对充填体中横向布筋与纵向布筋分别建立模型进行相似模拟试验,通过试验结果及试验过程监测数据分析,判别了顶板充填体的破坏机理,提出了充填体中布筋的合理方式,提高了顶板的稳定性,确保了回采过程的安全.     

采空区锚杆支护设计原理与分析

采空区下大跨度松软煤层巷道围岩稳定性控制问题,两帮及底板的控制难度都很大,顶板的安全状况差,是煤巷锚杆支护所面临的突出难解决的课题之一,必须引起高度重视,该类巷道围岩稳定性控制技术研究具有一定的挑战性.该文针对淮南矿区采空区下破碎不稳定顶板煤巷的特征,通过对破碎不稳定顶板煤巷锚杆支护理论进行分析,采用高强度锚杆支护系统,使巷道围岩保持稳定,满足了正常生产需要.     

China's Major Non-ferrous Metals Imports & Exports

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Zinc Production by Province in 2014

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80% of Chinese Firms Purchasing Overseas Mines Ended up in the Red

<正>Minmetals Resources acquired the world’s largest copper mine under construction for USD5.85 billion.One after another,listed companies Jien Nickle,China Molybdenum and Chihong Zinc and Germanium raised money to get involved in overseas mining projects…SOEs and private enterprises are engaged in a frenzy of overseas mine purchasing.A reporter with Economic     

Copper Processing Profit Dropped Sharply,Copper Consumption Will Face Impact in the Second Half of the Year

正Judging from China’s copper consumption field,the biggest consumption unit is electric power,which accounts for 47%of total consumption;it is followed by light industry sector,including household electrical appliance,machinery,durable goods and hardware etc,which accounts for 22%of total consumption;followed by transportation field,     

Central Geological Prospecting Fund Newly Added 16.47 Million Tonnes of Bauxite in 2013

正In 2013,the Central Geological Prospecting Fund(CGPF)Project newly discovered 15 ore fields,including 3 large above ore fields,and 5medium sized ore fields.The reporter learned from the recently published"Annual Report of Central Geological Prospecting Fund Project(2013)"that,from 2006 to 2013 the CGPF     

Manufacturers of Copper Tube for Central Air Conditioner Use Face Mounting Pressure in the Final Quarter of the Year

正This year,the investment growth rate of real estate industry continued to slow down,sold area of commercial housing also dropped significantly,which brought huge pressure to the domestic air conditioning manufactures.In the first half of the year,by relying on high growth in national financial expenditure,along with investment in public infrastructure     

Xinjiang Ranks No.1 in Production of Primary Aluminum in China

正Kang Yi,Honorary Chairman of China Nonferrous Metals Industry Association,said recently at the Forum on Development of the Non-ferrous Metals Industry in Central and Western China held in Zhengzhou that,as more and more electrolytic aluminum factories in Xinjiang came into operation,the electrolytic aluminum output of Xinjiang had reached2,275,000 tons in the first 7 months this year,     

Shenhuo Coal Industry and Electricity Power Completed800,000 t/a Aluminum Project in Xinjiang

正"Xinjiang project has been completed according to schedule,but total completion and total start of production are two different concepts,after completion it still needs a gradual process of reaching production target."On the morning of November 3,Shenhuo Coal Industry and Electricity Power told investors the above statement on the investor interaction platform.     

Guangdong Metal Transaction Center has Become the Second Largest Precious Metal Transaction Platform Nationwide

正The reporter learned from Guangdong Province Precious Metal Transaction Center that in 2013the Center maintained healthy development momentum,and had become the second largest precious metal transaction platform in China in terms of market size;currently Guangdong is quickening steps of financial innovation for the Center,aiming to build a transaction center with international core competitiveness.     

Seven Rare Earth Projects Involving Close to 3 Billion Yuan Investment Landed In the HighTech Zone

正On May 22,Baotou Rare Earth Industry Cooperation Consultation MeetingProject Agreement-signing Ceremony was held in Ningbo,nearly 40 enterprises from Ningbo,Guangdong,Hunan,and Shanxi participated in project consultation.After multi-lateral communication,agreements were signed for a total of 7 rare earth projects successfully.