江苏松散沉积层地区地下水资源评价模型发展趋势          下载免费PDF全文

施春华  骆祖江 《江苏地质》2010,34(1):36-40

江苏松散沉积层厚度大、结构复杂、容易发生固结压缩,地下水可采资源量评价具有较大的不确定性,容易造成重复或缺失,地下水的过量开采又容易引发地面沉降地质灾害。针对以上问题,提出了地下水资源评价的地下水渗流三维数学模型及其地下水渗流与地面沉降耦合模型。地下水渗流三维数学模型可以将整个松散沉积层作为一个统一的水文地质体进行计算,对不同水力性质的含水层同时进行刻画描述,克服了以往二维或准三维模型将各含水层之间的粘性土层概化为越流层给评价结果带来的重复或缺失。地下水渗流与地面沉降耦合模型可以结合地面沉降环境控制,评价出地下水的可采资源量,尤其是以比奥固结理论为基础,考虑了土体的非线性特征及土的渗透性随应力状态的动态变化的全耦合模型,使评价结果更趋科学、合理。  相似文献   

天津市中心城区地下空间资源开发利用适宜性评价探讨     

齐波  张一飞 《城市地质》2010,5(2):1-5

探讨了天津市中心城区的地下空间资源开发利用评价,提出了地下空间资源开发利用评价方法。分析了天津市中心城区的地质背景,论证选取了适宜的评价因子,结合目前中心城区地下空间的开发利用现状,对中心城区地下空间资源的开发利用进行了适宜性分区评价,为将来天津市中心城区地下空间资源的合理开发利用提出了建议。  相似文献   

基于组合楔形体原理的采动坡体稳定性研究     

史文兵  黄润秋  赵建军 《工程地质学报》2014,22(6):1168-1175

地下采煤通常会引起地表严重开裂,甚至发生滑坡、崩塌等地质灾害,采动坡体的稳定性研究一直是工程实际关心的问题。本文以贵州省都匀市煤洞坡采动坡体为例,在斜坡破坏机制分析基础上,采用组合楔形块体原理构建了采动坡体稳定性系数计算方程,并从实验、经验类比、采空率等方面对采动坡体的强度指标进行了综合取值,计算了采动坡体在天然、饱水及裂隙水作用下的安全系数。结果表明:煤洞坡山体是处于稳定状态的,这与坡体上的裂缝位移监测成果是相符的。但在长时间降雨或暴雨情况下,煤洞坡山体稳定性就会逐渐变差,甚至发生滑动; 坡体稳定性安全系数随内摩擦角的降低而降低,随裂隙水充水高度的增加而降低; 一旦后缘块体挤压前缘块体时,就会存在一个安全系数急剧降低的阀值。从裂缝水柱高度与降雨渗入裂缝的雨水量关系出发,建立了裂缝水柱高与降雨量之间关系式。经计算当降雨量(短时间内)超过192mm,斜坡就会失稳。  相似文献   

Robust geotechnical design of shield-driven tunnels     

《Computers and Geotechnics》2014

This paper presents a fuzzy set-based robust geotechnical design (RGD) methodology for the design of shield-driven tunnels. Here, uncertain geotechnical parameters required for analysis of tunnel performance (referred to herein as the structure safety and serviceability performance of tunnel cross section) are represented as fuzzy sets. Given fuzzy input parameters, the performance of a shield-driven tunnel will be uncertain, which is expressed in this study as a fuzzy factor of safety, according to the analysis of vertex method. Then, the fuzzy factor of safety for a given design is used to evaluate the failure probability and design robustness, which are, in turn, employed in the proposed RGD framework. Note that a design is considered robust if the performance of the shield-driven tunnel is insensitive to the variation of its uncertain geotechnical parameters. Within the RGD framework, each candidate design in the design space is analyzed for its safety state (in terms of failure probability), design robustness, and cost. The goal of the RGD of a shield-driven tunnel is to bring the safety state to an acceptable level, while maximizing the robustness and cost efficiency simultaneously. To this end, a multi-objective optimization is performed and a Pareto front is obtained, which provides a trade-off that may be used to select the most preferred design. Through an illustrative case, the effectiveness and significance of this new robust design methodology is demonstrated.  相似文献   

我国生态文明评价指标体系综述     

符蓉  张丽君 《国土资源情报》2014,(10):2-8

在推进生态文明建设的背景下,构建生态文明评价指标体系对生态文明发展状况进行监测和预警,为生态文明建设提供决策支持,具有十分重要的意义.本文根据生态文明的本质内涵,回顾了可持续发展概念自提出以来生态文明评价指标体系的发展历程,对我国生态文明建设相关的评价指标体系进行归纳和总结;重点以政府管理实践中的生态文明评价指标体系为例,分析了我国生态文明评价指标体系的特征与存在的问题.  相似文献   

Where is my neighborhood? A dynamic individual-based definition of home ranges and implementation of multiple evaluation criteria     

《Applied geography (Sevenoaks, England)》2017

With the growing interest in studying characteristics of geographical context and its influence upon people, the concept of home range has been a focus of scholarly research. Home ranges are studied extensively across multiple disciplines, with literature supporting different operationalization techniques. This article argues that many of the existing approaches are not dynamic and versatile enough and do not provide reliable solutions for estimating individual home ranges. We additionally argue that many of current studies lack robust evaluation approaches. Recent evidences suggest that the usual approaches, which often exclusively rely on a single validation criterion, are not reliable and may be influenced by inferential errors. This study aims to tackle the exiting limitations in definition and operationalization of individual-based home range models and provide a more robust solution for their evaluation and comparison. Using data collected through public participation GIS we develop an applied, dynamic, and parametric model of individual home ranges. Subsequently, we propose multiple criteria comprising five validation hypotheses to evaluate model's effectiveness. We argue that application of this approach in evaluating spatial delimitation models can ameliorate the risk of biased validation resulting from inferential errors. The evaluation results indicate a substantial improvement in coverage of visited points compared to previously used static methods. Consequently, this paper draws a number of conclusions that can serve as guidelines for future research. This paper highlights the strengths and weaknesses of the proposed method and explains how it can be improved and employed in future studies investigating contextual effects on residents.  相似文献   

射电天文台址电子设备电磁辐射评估     

刘奇  陈卯蒸  李颖  张群涛 《天文研究与技术》2015,(3)

射电望远镜具有极高的系统灵敏度,且系统内、系统间及台址内电子设备众多,电磁环境复杂,科学合理地评估台址内电子设备辐射发射对射电天文观测的影响,对系统电磁兼容性设计、无线电管理、屏蔽改造等有重要的指导意义。浅析了射电望远镜系统灵敏度及射电天文领域仪器设备辐射发射相关评估标准;基于射电望远镜系统灵敏度及观测需求,计算了南山25 m射电望远镜馈源口面干扰电平限值,并给出了天线旁瓣增益的计算方法;提出一种基于干扰电平限值、旁瓣增益、干扰测量、路径衰减的电子设备电磁辐射评估方法,并针对南山25 m射电望远镜天线驱动电磁辐射进行了评估,给出了屏蔽需求。  相似文献   

辽河三角洲湿地生态服务功能价值评估研究   总被引：1，自引：0，他引：1  

刘新宇  李艳  王金爽  魏岩  于长斌  裴艳 《湿地科学与管理》2012,8(3):12-14

采用国际通用的市场价值法、成本法、影子工程法和替代法,对辽河三角洲湿地服务功能价值进行评估研究,诠释了保护湿地资源的重大意义。  相似文献   

闽江河口湿地自然保护区生态系统服务价值评价   总被引：2，自引：0，他引：2  

傅娇艳 《湿地科学与管理》2012,(4):17-19

研究运用生态经济学和资源环境经济学等有关理论和研究方法,利用前人已有调查资料,对闽江河口湿地自然保护区生态系统服务价值做了较全面的评价,拟为保护湿地和公共决策提供科学依据。闽江河口湿地自然保护区生态系统服务价值为4966.1万元/a。按照价值量大小排序为:调节气候价值>文化载体价值>保护生物多样性价值>提供产品价值。  相似文献   

基于GIS的金属矿山安全信息系统的实现     

陈首彬  赫晓慧  李楠楠 《测绘软科学研究》2012,(5):57-59,64

将地理信息系统（GIS）、数据库等技术运用到金属矿山安全生产中,设计并开发了基于GIS的金属矿山安全信息系统。本文重点阐述该系统的总体设计、数据库设计和核心功能实现。系统可进行地图管理、信息查询等基本操作和金属矿山的安全评价、事故预警,以及矿区地形的DEM分析,为金属矿山的安全生产提供科学指导。  相似文献