大庆地区水环境承载力计算分析与评价

为探索科学、合理、可持续开发和保护水资源的有效途径,实现水资源有效、安全利用,对大庆地区水环境承载力进行分析与评价.针对大庆地区水环境现状建立合适的水环境评价指标体系,应用各评价指标承载度模型计算得出各评价指标承载度,各评价指标承载度通过水环境承载力模型进行综合计算,得出大庆地区水环境承载力.分析大庆地区水环境承载力现状以及动态变化趋势,找出影响大庆地区水环境承载力的主要因素.结果表明,大庆地区水环境承载力较低并呈现逐年降低的趋势,主要是水资源短缺、水资源利用率过大造成的.     

基于RS和GIS的贵州大湾煤矿区矿山地质环境评价

根据贵州大湾煤矿区矿山开发多目标遥感调查资料,利用RS与GIS技术,在综合考虑研究区自然地理、地质背景、资源损毁、地质环境等基础上,构建了4个子评价系统15个指标因子的评价指标体系;用层次分析法来确定评价因子的权重,选用加权综合评价法,对贵州大湾煤矿区矿山地质环境进行了定量评价,并绘制了研究区矿山地质环境综合评价图;通过与矿山地质环境现状对比分析,其结果相吻合,评价结果真实反应研究区矿山地质环境现状。     

基于FAHP和Kriging算法的矿山地质环境评价系统

矿产资源在开采过程中会对矿山及其周围地质环境造成影响,科学评价矿山地质环境是矿山治理与改善的基础。文章建立了矿山地质环境评价系统,采集矿山评价指标和专家评价结果,基于模糊层次分析法(FAHP)建立诊断树模型,评价了矿山破坏程度,采用克里金插值算法(Kriging)计算矿山及周围环境的空间相关性和依赖性,利用网络地理信息系统(WebGIS)技术可视化展示矿山区域的地质环境。结果表明：FAHP能够有效地评价矿山及其周围地质环境的状态,WebGIS技术与Kriging算法相结合的可视化手段能够更准确地展示矿山受影响的区域与损害程度,为矿山地质环境的评价提供了有力的技术支撑。     

基于层次分析法的矿山地质环境评价——以北山成矿带为例

根据北山成矿带矿区矿山自然地理、地质背景、矿山开发影响等实际因素,利用层次分析法建立矿山地质环境评价子系统和评价指标,确定评价因子及各指标权重,分别获得子系统权值和评价指标权值,并基于Arc GIS平台通过网格法对整个研究区进行矿山地质环境综合评价,利用模糊数学法将研究区地质环境分为无影响区、一般影响区、较严重影响区和严重影响区4级,最后针对每个影响区进行环境评价及分析。     

淮北平原地基分层与承载力的BP网络预测方法

针对淮北平原地质土成层性和不均匀性显著的特点,提出了多元互层地基分层和承载力分层计算的BP神经网络预测方法。以钻探取样、静力触探试验和螺旋板载荷试验、平板载荷试验原位测试结果进行对比,认为比贯入阻力ps值可以作为互层地基分层和地质土承载力预测的评价指标,并以此为基础采用BP神经网络的梯度下降算法和共轭梯度算法分别建立土质分层和承载力预测的模型,并将两种算法的计算结果进行了对比分析。结果表明：比贯入阻力值可作为淮北平原互层地基的土质分层和承载力预测的评价指标;BP神经网络的梯度下降算法和共轭梯度算法均对土质类型的识别和地基承载力的预测具有良好的效果,满足实际工程的精度要求,但是前者的计算效率明显低于后者。     

公路项目可持续发展的评价方法

为评价公路项目对社会、经济可持续发展的贡献,建立了公路项目可持续发展的三级评价指标体系(目标层指标、准则层指标、指标层指标).运用模糊数学理论,建立了NPV、Nd、IRR、BCR的隶属函数.运用集值统计方法对各项指标进行无量纲化处理,得到无量纲矩阵.通过对定量与定性评价指标的评判,得到单因素评价矩阵.运用AHP法,对备选方案作相对评价和综合评价,确定各因素的权重,排出各方案的优劣次序.根据最大隶属原则,求得公路项目可持续发展的最终评价结果.揭示了公路项目对社会、经济、环境的影响.     

基于载体-载荷视角的资源环境承载力评价——以济南市为例全文替换

资源环境承载力是指导城市发展和优化国土空间保护格局的基础,但对其的定义和评价方法还未达成共识。文章在对城市系统分析的基础上,而将城市载体也划分为自然资源、环境吸收、生态服务、社会支持4个维度;将城市载荷划分为人口、社会经济发展水平及结构、资源消耗、环境污染4个维度。从本质上阐明资源环境承载力的内涵。利用理论分析和频度分析的方法选取具有代表性的指标;利用熵值法和线性加权的方法计算出支持力指数、压力指数和城市资源环境承载力指数。以济南市为例,评价了2009—2019年的城市资源环境承载力,发现环境吸收能力为最主要的短板因素,在研究期内济南市资源环境系统经历了由整体超载风险较高到承载能力过剩的转变,目前发展可持续性较好。     

区域水资源承载力评价的风险矩阵方法

为客观合理地评价水资源承载力和综合考虑各要素的评价结果,从承载支撑力和承载压力两方面出发,选取水量、水质要素承载支撑力和压力评价的实物量指标,建立了水资源承载力评价指标体系,构建了区域水资源承载力评价的风险矩阵方法(RMM-WCC),采用短板法进行单要素水资源承载力评价,运用风险矩阵方法对单要素评价结果进行综合,最后得到水资源承载力评价的综合评价结果。将RMM-WCC应用于安徽省淮河流域的水资源承载力评价中,得到该区域的水资源承载状态,对于超载的状态指出了超载原因,并给出了相关的措施建议。该评价结果可为安徽省淮河流域水资源优化配置提供参考,同时,RMMWCC在水土资源、生态环境和海洋资源等承载力综合评价中具有广泛的应用前景。     

利用遥感和GIS进行四川省生态安全评价研究

四川省生态安全评价对其生态安全建设具有极其重要的意义。为此,该文利用地理信息技术、遥感技术和层次分析技术对四川省的生态安全评价进行了研究。建立了适用于四川省的生态安全评价指标体系,该指标体系由目标、准则和指标三个层次构成。在指标层中包含了反映自然、人文和污染等方面的14个指标,用遥感和GIS获取处理相关指标。利用层次分析法确定各指标的权重,使用GIS建立生态安全评价的相关模型。最后,以市州为单元,利用相关评价模型对自然生态环境状态、人文社会压力安全、环境污染压力安全和区域生态安全等指数进行评价和定级。该研究表明,利用遥感、GIS和AHP能有效地实现区域生态安全评价,且结果可示以图表。     

秦岭北麓露天矿区地质环境评价

为了揭示秦岭北麓矿山开采对生态环境的影响,利用现场调查和遥感解译相结合的方法开展了矿山地质环境问题调查。选取地质环境条件、地质灾害发育情况以及破坏治理现状为中间变量层,各变量层分别包括微地貌、水文地质、地层岩性,崩塌灾害、泥石流灾害,弃渣压占现状、土地复垦现状和灾害防治现状等影响指标层,利用层次分析法(AHP)确定各影响因子的权重并结合ArcGIS的空间分析功能进行了矿山地质环境评价分区。结果表明:研究区山地与台塬交接的山麓地带地层岩性较差、崩塌灾害严重,东部202省道沿线地区废渣占压问题严重、泥石流灾害发育。矿山所在区域的地质环境综合评价多为中和差,且202省道沿线的环境条件尤为恶劣,这一评价结果与秦岭北麓的现场调查结果具有较好的一致性。评价结果可为政府等有关部门开展矿山地质环境恢复治理工作提供理论依据。     

山东省水生态环境承载力探讨

水生态环境承载力可以作为衡量区域经济社会与水生态环境协调程度的判据.以生态环境需水量和水环境容量作为水生态环境承载力研究的基础,构建了山东省水生态环境承载力评价指标体系,进行了单项指标评价;建立了水生态环境承载力综合评价方法,并对山东省2000～2005年水生态环境承载力进行了综合评价.研究成果为有关决策部门指导水环境管理、水资源保护和推进生态省建设提供了科学依据.     

传统工业型城市综合生态承载力评价——以株洲市为例

从城市生态系统支撑力、社会经济协调力、人类活动压力3个方面构建了城市综合生态承载力评价指标体系,并运用组合赋权法和状态空间法相结合的手段,以株洲市为基本评估单元,对该市2007—2018年城市综合生态承载力进行评估,探究了影响区域综合生态承载力的关键因素.结果表明:株洲市综合生态承载力总体呈现小幅度波动上升的发展态势,...     

Fuzzy Evaluation of Coal Seam Geological Condition of Fully-Mechanized Face in Ten-Million-Ton Mine

1 IntroductionWith the development of coal mining, the dif-ference in coal seam geological conditions will cer-tainly influence on the adaptability of coal miningtechnology and on coalface outputs, especially theeconomic indicators. To ensure a high efficiency ofcoal mining, coal seam geological conditions mustbe made clear. Fuzzy evaluation here is aiming atconcrete coal seam geological conditions with thecomprehensive view of coal mining. The main ideaof this evaluationis that a coalface is …     

粘性土塑性指数与粘粒含量的线性回归分析

以浙江某地区粘土为例,对饱和软粘土的塑性指数与粘粒含量的关系进行回归计算．用密度计法测得粘性土的粘粒含量,用液塑限联合测定仪测出粘性土的塑性指数,并对二者进行线性回归分析,得出粘性的塑性指数与粘粒含量的线性回归方程,证明了粘性土的粘粒含量与塑性指数存在很好的对应关系,从而省略密度计试验繁琐的试验过程,简化计算,提高了工作效率和数据的精度．     

Risk assessment of fault water inrush during deep mining

With the gradual depletion of shallow coal resources, the Yanzhou mine in China will enter the lower coal seam mining phase. However, as mining depth increases, lower coal seam mining in Yanzhou is threatened by water inrush in the Benxi Formation limestone and Ordovician limestone. The existing prediction models for the water burst at the bottom of the coal seam are less accurate than expected owing to various controlling factors and their intrinsic links. By analyzing the hydrogeological exploration data of the Baodian lower seam and combining the results of the water inrush coefficient method and the Yanzhou mine pressure seepage test, an evaluation model of the seepage barrier capacity of the fault was established. The evaluation results show the water of the underlying limestone aquifer in the Baodian mine area mainly threatens the lower coal mining through the fault fracture zone. The security of mining above confined aquifer in the Baodian mine area gradually decreases from southwest to northeast. By comparing the water inrush coefficient method and the evaluation model of fault impermeability, the results show the evaluation model based on seepage barrier conditions is closer to the actual situation when analyzing the water breakout situation at the working face.     

青东矿10煤层水文地质特征及充水因素分析

为了评价10煤层开采可能产生的水害影响,根据矿井含、隔水层的水文地质特征,指出10煤层受采动破坏,顶底板砂岩裂隙水、太原组和奥陶系岩溶水沿采动裂隙和断层溃入矿井,对矿井开采形成威胁。根据对矿井充水因素的分析,得出矿井的充水强度不大,充水通道主要为隔水层薄弱地段采动裂隙和断层破碎带。     

Research on Evaluation of Degree of Complexity of Mining Fault Network Based on GIS

A large number of spatial and attribute data are involved in coal resource evaluation. Database is a relatively advanced data management technology, but its Major defects are the poor graphic and spatial data functions, from which it is difficult to realize scientific management of evaluation data with spatial characteristics and evaluation result maps. On account of these deficiencies, the evaluation of degree of complexity of mining fault network, based on GIS, is proposed, which integrates management of spatial and attribute data. Fractal is an index which can reflect the comprehensive information of faults＇ number, density, size, composition and dynamics mechanism. Fractal dimension is used as the quantitative evaluation index. Evaluation software has been developed based on a component GIS-MapX, with which the degree of complexity of fault network is evaluated quantitatively using the quantitative index of fractal dimensions in Liuqiao No.2 coal mine as an example. Results show that it is effective in acquiring model parameters and enhancing the definition of data and evaluation results with the application of GIS technology. The fault network is a system with fractal structure and its complexity can be described reasonably and accurately by fractal dimension, which provides an effective method for coal resource evaluation.     

A review of cavability evaluation in longwall top coal caving

Longwall Top Coal Caving has been considered as one of the most effective technologies for the extraction of underground thick coal seams. A large number of studies on the applicability of Longwall Top Coal Caving into new mine sites have linked the success of its application to the geo mechanical understanding of the cavability of the top coal. The paper aims to improve the knowledge of the top coal cavability evaluation. A range of parameters that affect the top coal cavability were first identified. Afterward, a number of cavability assessment methods and classifications were reviewed. The result is important in that it assists researchers in developing an advanced and reliable tool for the top coal cavability evaluation.     

AHP-RBF神经网络在煤矿安全风险评价中的应用

煤矿生产的复杂性导致煤矿事故具有动态、随机、模糊的特性,而且影响煤矿安全风险等级的指标众多,风险等级与风险指标之间呈现出复杂的非线性关系。传统的BP神经网络评价方法的准确率低,本文提出一套新的煤矿安全风险评价方法。首先建立煤矿安全风险指标体系,然后利用AHP确定各风险指标权重,并对其进行重要性排序,最后将RBF神经网络作为评价工具,建立基于AHP-RBF神经网络的煤矿安全风险评价模型。通过案例分析表明该模型能够科学有效的对煤矿安全状况进行评价。     

Coal pillar mechanics of violent failure in U.S. Mines

This paper seeks to enhance the understanding that the horizontal stresses build up and release during coal pillar loading and unloading(post-failure) drawing upon three decades of observations, geomechanical monitoring and numerical modeling in bump-prone U.S. mines. The focus is on induced horizontal stress in mine pillars and surrounding strata as highly stressed pillars punch into the roof and floor, causing shear failure and buckling of strata; under stiff stratigraphic units of some western US mines, these events could be accompanied by violent failure of pillar cores. Pillar punching eventually results in tensile stresses at the base of the pillar, facilitating transition into the post-failure regime; this transition will be nonviolent if certain conditions are met, notably the presence of interbedded mudstones with low shear strength properties and proper mine designs for controlling seismicity and dynamic loads. The study clearly shows high confining stress build-up in coal pillars resulting in up to twice higher peak vertical stress and high strain energy accumulations in some western US mines in comparison with peak stresses predicted using common empirical pillar design methods. It is the unstable release of this strain energy that can cause significant damage resulting from pillar dilation and ground movements. These forces are much greater than the capacity of most common internal support systems, resulting in horizontal stressinduced roof falls locally, in mines under unremarkable far-field horizontal stress. Attention should be placed on pillar designs as increasing support density may prove to be ineffective. This mechanism is analyzed using field measurements and generic finite-difference stress analyses. The study confirms the higher load carrying capacity of confinement-controlled coal seams in comparison with structurally controlled coal seams. Such significant differences in confining stresses are not taken into account when estimating peak pillar strength using most common empirical techniques such as those proposed by Bieniawski and Salamon. While using lower pillar strength estimates may be considered conservative,it underestimates the actual capacity of pillars in accumulating much higher stress and strain energies,misleading the designer and inadvertently diminishing mine safety. The role of induced horizontal stress in mine pillars and surrounding strata is emphasized in coal pillar mechanics of violent failure. The triggering mechanism for the violent events is sudden loss of pillar confinement due to dynamic loading resulting from failure of overlying stiff and strong strata. Evidence of such mechanism is noted in the field by observed red-dust at the coal-rock interfaces at the location of coal bumps and irregular, periodic caving in room-and-pillar mines quantified through direct pressure measurements in the gob.