基于DDEM的自然崩落采矿法崩落规律的数值模拟   总被引：1，自引：1，他引：0  

姜增国  杨保仓 《岩土力学》2005,26(2):239-242

利用DDEM（可变形离散单元法）原理和方法,研究了自然崩落法矿体崩落规律。针对具体地质条件和赋存情况及矿岩物理力学性质,采用计算机数值模拟分析了自然崩落法的崩落规律,得出了DDEM在用于模拟矿块自然崩落法中崩落规律和分析其崩落机理时是较适合的结论,不仅可以从力学角度对崩落的力学机理进行研究,而且能直观地用图形给出矿体在崩落过程中的具体形态变化,有效地指导放矿,现场试验验证效果良好。  相似文献   

雅江县额稀沟堆积扇成因分析及工程意义     

刘维国  沈军辉  章志峰  王者涛  贾留杰 《山地学报》2009,27(2)

额稀沟为雅砻江右岸一级支流,位于雅江县城北,近沟口一带及其沟口下游雅砻江两岸残存发育有堆积体。从堆积体总体分布形态、堆积体成分及结构的空间变化特征,恢复了发生于末次冰期晚期的额稀沟巨大古洪积扇,并根据洪积物的物质组成及结构特征,合理选取了岸坡坍岸预测的计算参数,计算参数选取实验数值中偏大值。采用geo-slope软件自动搜索危险滑面和王跃敏的图解法,预测了Ⅳ区堆积体岸坡在牙根水库蓄水条件下坍岸范围,结果表明：2602m水位条件下坍岸宽度为28m,仅比2587m蓄水位条件下坍岸宽度20m扩大了8m。成果将直接应用于雅江县安全评价、县城搬迁范围划定以及牙根水库2587m、2602m水位线比选,亦对雅江县城环境地质条件认识具有一定意义。  相似文献   

大口径钻孔桩孔壁稳定分析研究   总被引：1，自引：0，他引：1       下载免费PDF全文

罗绍明  朱文鉴 《探矿工程》2000,(1):35-37

从理论上分析并结合实践经验 ,提出了大口径钻孔桩孔壁稳定的 3个条件 ,即静力平衡、地质渗流、时间因素 ,在此基础上分析了影响孔壁稳定的各种客观、工艺、环境及人为因素 ,给出了预防和处理孔壁坍塌事故的措施。  相似文献   

崩落法转充填法采矿地表移动二维离散元程序数值模拟及其规律验证     

曹帅  杜翠凤  母昌平  雷远坤 《岩土力学》2015,36(6):1737-1743

基于数字式全景钻孔摄像系统及现场统计对井下矿体及围岩进行了节理调查分析,利用Surpac建立了采空区三维模型并进行剖分,最终建立了二维离散元模型（UDEC）,研究不同水平矿体开采时位移场的变化规律和采空区上覆岩层的冒落形式,记录并分析矿体开采过程中岩石移动角变化规律并进行了对比验证。研究结果表明：充填法开采-430～-500 m矿体时,采空区最大位移为205.6 cm,小于崩落法的215.2 cm;对比充填法和崩落法新副井沉降值和水平位移值发现,充填法地表倾斜率为0.56 mm/m,小于崩落法的1.22 mm/m,水平变形率为1.03 mm/m,小于崩落法的1.31 mm/m,对于控制新副井沉降和地表移动具有良好效果。在崩落法开采时覆岩移动存在一定间歇性和跳跃性,冒落过程中可能形成自稳平衡拱,从而形成隐伏采空区。根据实际监测与模拟结果对比,在同一水平开采时间较长时,移动角减小速率呈跳跃性非均匀变化,表现为缓慢变化-加速变化-缓慢变化-加速变化的循环过程,进一步验证了自稳平衡拱和隐伏采空区的存在。  相似文献   

顶板诱导崩落爆破效果的全景探测与评价     

胡建华  周科平  罗先伟  邓红卫 《岩土力学》2010,31(5):1529-1533

基于连续采矿的顶板诱导崩落技术,采用预裂爆破控制裂隙发展区间,强制崩顶爆破诱导顶板围岩裂隙发育、扩展,从而诱导顶板致裂失稳的可控崩落。然而在地下采空区顶板诱导致裂失稳崩落处理采空区过程中,预裂与崩顶爆破效果具有极大的隐蔽性,难以进行直观可视的评价。采用钻孔摄像系统,利用前视与全景可视技术,对顶板诱导爆破前钻孔形态和爆破的效果进行了探测,特别在爆破后的全景钻孔摄像,数字化描述了钻孔的裂隙特征,并通过钻孔摄像的图片分析评价了顶板诱导崩落爆破效果。全景探测的结果表明：（1）预裂爆破在顶板岩体中形成了清晰可见宽为20～40 mm的预裂缝,炮孔底部存在半个孔壁的预裂特征。（2）顶板围岩中产生了大量的次生诱导微裂隙带,裂隙交错呈“X”型,并且原生裂隙得到了扩展。（3）顶板诱导爆破实施后爆堆形状良好,大量裂隙发育以及碎裂岩体结构的形成有利于顶板的诱导可控崩落。  相似文献   

Stress Distribution During Extraction of Pillars in a Thick Coal Seam   总被引：1，自引：0，他引：1  

S. Jayanthu  T. N. Singh  D. P. Singh 《Rock Mechanics and Rock Engineering》2004,37(3):171-192

Summary This paper presents field observations on distribution of vertical stress during an experimental trial of extraction of pillars in four panels in 6.0–8.0m thick coal seam, as a part of a Science and Technology project funded by the Ministry of Coal, Govt of India. Variation of induced stress based on continuous monitoring data for the first time in Indian coal mining scenario showed distinct anomalies and potential for better understanding of strata mechanics and warning of major roof falls during pillar extraction. Numerical model studies based on finite difference code – FLAC were also conducted for stress analysis in idealized pillar mining sequence so that the influence of each stage of extraction could be identified. The numerical model results on stress concentration over the pillars, stooks and ribs showed variation of 3.6%, 8.3% and 6.1%, respectively as compared to the field observations for 7m thick coal seam at a depth cover of 60m from the surface. This indicates validity of the numerical models for stress analysis in the simulated conditions of the present field experiments.  相似文献   

三维渗流模型模拟采空区注浆治理过程的研究     

王万顺耿玉岭  范运岭 《中国煤田地质》2005,17(1):22-25

在某高速公路采空区优化治理与质量检测研究课题中首次采用三维渗流方程对采空区冒落带、裂隙带的注浆过程进行了数值模拟，其结果令人满意。根据设计的注浆压力和地层条件，利用数值模型来求得注浆量及注浆半径(包括冒落带和裂隙带)，为优化设计提供依据。  相似文献   

ITK应用在架空送电线路勘测中的探讨     

于世岩  林海陈强 《测绘与空间地理信息》2007,30(3):52-55,59

主要通过常规传统勘测和RTK勘测的比较介绍了架空送电线路勘测技术的更替，并结合RTK专业电力软件在重庆永川110KV交流超高压输送电线路改线测量中的应用与实施，探讨RTK电力数字化有码作业方式的有效应用。  相似文献   

The causes of cyclic excessive convergence at the longwall tailentry     

S. S. Peng  W. H. Su 《Geotechnical and Geological Engineering》1983,1(1):27-41

Summary Longwall panel layouts in the USA differ from other countries in that each panel is blocked out at both sides by at least three parallel panel entries separated by chain pillars. The panel entries may vary in width up to 90 m depending on local conditions.A finite element analysis in two and three dimensions of hypothetical longwall prototypes in the Pittsburg seam, where significant tailentry closure has been reported was carried out. This showed that convergence of tail and head entries undergoes cyclic variation, the period of which depends on the strength and thickness of competent roof layers and their location relative to the face geometry. The panel width was found to have a particular effect on the period and amplitude of potential cyclic phenomena.  相似文献   

A rock mass classification model for caving roofs     

A. K. Ghose  D. Dutta 《Geotechnical and Geological Engineering》1987,5(3):257-271

Summary Evaluation of the caving behaviour of longwall roof rocks has thus far been based on a pot-pourri of classification systems, which ignore basic caving criteria. The paper outlines a new classification model of roof strata namely cavability using fuzzy set methodology and linguistic variables to assign ratings for individual roof beds. A microcomputer program has been developed to evaluate the decision ratings for cavability and the model applied to ten longwall case-histories from Indian coalfields. The classification model has excellent potential for being used as a standard tool for the evaluation of caving behaviour of longwall roof rocks.  相似文献