某场地边坡稳定分析方法的比较研究*

为了对边坡稳定性分析方法进行研究,以某场地高填方边坡和直立边坡为研究对象,基于Geostudio、理正软件以及ANSYS软件,采用M-P法、Bishop法和强度折减法进行边坡稳定分析。结果表明:高填方边坡安全系数为1.3,为稳定边坡;AB,BC,CD段地块间边坡边坡安全系数依次为0.479,0.410,0.381,基坑边坡安全系数为0.436,均为不稳定边坡;其中,M-P法得到的安全系数偏保守,Bishop法得到的安全系数结果较可靠,强度折减法得到的结果最为理想。研究结果可为边坡稳定性研究与治理提供借鉴。     

城市垃圾填埋场覆膜内的甲烷及恶臭物质特征研究

卫生填埋是常用的固体废弃物处置方法。部分填埋场对已经封场和暂时不填埋垃圾的区域覆盖高密度聚乙烯膜(HDPE),便于雨水分流、减少垃圾渗滤液产生量。通过在华北地区某城市生活垃圾卫生填埋场设置采样点,监测分析了HDPE覆膜内积聚的甲烷及恶臭物质的浓度和成分,研究在不同季节、填埋时间产生的甲烷及恶臭物质特征。结果表明:填埋场覆膜内甲烷的平均浓度为15.6%;硫化物、胺类以及恶臭浓度分别为153.9 mg/m3,16.0 mg/m3以及4 322 OU。主要的恶臭物质为硫化氢和氨。总挥发性有机物的浓度为0~147.2 mg/m3,苯系物、烷烃和烯烃是挥发性有机物的主要成分。恶臭浓度与硫化物、胺类浓度具有明显的相关性。环境温度、垃圾填埋龄和填埋量对甲烷及恶臭物质的产生与释放有明显影响。夏季甲烷及恶臭浓度分别达到81.2%和20 943 OU,明显高于其他季节。随着垃圾填埋龄和填埋量的增加,恶臭物质的浓度和成分均发生显著变化。     

生活垃圾卫生填埋场渗滤液处理系统工程设计

本文从工程的角度出发对垃圾填埋场渗滤液处理系统工程设计中的几个重点、难点计算参数,以及目前国内外几个典型垃圾填埋场的渗滤液处理工艺流程、处理效果做了介绍,并在此基础上提出了几点建议     

生活垃圾卫生填埋场渗滤液的控制和管理

生活垃圾的卫生填埋处理是目前我国生活垃圾处理的主要方法,而垃圾填埋产生的渗滤液是污染环境的重要隐患。对垃圾渗滤液的主要来源及水量的影响因素、主要特点进行了综述,并就如何控制处理和管理好垃圾渗滤液提出了对策措施。     

高速铁路高填复合路堤边坡安全问题探讨

路基是高速铁路安全系统的关键和薄弱环节 ,建在软土上的高填路堤边坡是否稳定 ,更是直接关系到路基乃至整个高速铁路系统的安全 ,采用桩—网复合地基形式修建高路堤是一个好办法 ,这种路堤形式尚不多见。笔者结合其特点 ,从理论上提出了一种新的边坡安全实用计算方法 ;讨论了影响边坡安全的主要因素 ;验证了这一计算方法的合理性     

垃圾污染质在天然黏土屏障中运移情况的调查

通过对杨府山垃圾卫生填埋场的实地调查,重点调查了距垃圾场外边缘以南500m土壤中重金属含量,与国家环保局给出的土壤背景值比较,发现对人类健康有较大影响的Pb,Mn,Cu,Cd的浓度值均大大超过国家规定标准,污染指数分别达到了5.9959,2.0974,4.2021,2.4864,9.2204,其中镉的污染最为严重,并讨论了天然黏土屏障在污染质运移过程中的控制作用,及今后屏障材料的发展方向。该研究结果对该地区进行环境治理的必要性提供了科学依据。     

Coal-Mine Hollow Fill and Settling Pond Influences on Headwater Streams in Southern West Virginia, USA

The influences of coal-mine hollow fills and associated settling ponds in three headwater streams were assessed in southern West Virginia, USA. Fill drainage waters had elevated conductivities and metal concentrations, compared to a regional reference. Benthic macroinvertebrate richness was not affected consistently by the hollow fill drainages, relative to a regional reference, although a more tolerant community, lacking in Ephemeroptera taxa at most locations, was evident. Collector-filterer populations were elevated at monitoring stations directly below the settling ponds, indicating that the ponds’ presence influenced macroinvertebrate community structure by means of organic enrichment. Corbicula fluminea growth was enhanced in monitoring locations directly below the settling ponds, also an apparent result of organic enrichment. Results of acute water column toxicity testing with Ceriodaphnia dubia, sediment chronic toxicity testing with Daphnia magna, and in-situ ecotoxicological assessments with C. fluminea demonstrated no mortality or toxic influence at most of the sites tested below the ponds. The settling ponds appear to serve as sinks in collecting some, but not all, trace metals.     

GROUND AND SURFACE WATER QUALITY IMPACTS OF NORTH CAROLINA SANITARY LANDFILLS1

ABSTRACT: Ground and surface water quality monitoring data from 71 municipal sanitary landfills in North Carolina were analyzed to determine the nature and extent of current contamination problems and identify any common characteristics associated with this contamination. A total of 322 surface and 411 ground water quality records were analyzed using the SAS data system. Almost all the landfill records included inorganic and heavy metal analyses while approximately half of the records also included organic analyses by CC/MS. Our analysis indicates that landfills are having measurable impacts on ground and surface water quality, but these impacts may not be as severe as is commonly assumed. Statistically significant increases were detected in the average concentrations in ground water and downstream surface water samples when compared to upstream surface water samples. The largest percentage increases were observed for zinc, turbidity, total organic carbon, conductivity, total dissolved solids, and lead. Violations of ground water quality standards for heavy metals and hazardous organic compounds were detected at 53 percent of the landfills where adequate data existed. The moat common heavy metal violations were for lead (18 percent), chromium (18 percent), zinc (6 percent), cadmium (6 percent), and arsenic (6 percent) (percentage of landfills violating shown in parenthesis). The organic compounds that appear to pose the greatest threat to ground water are the chlorinated solvents (8 percent), petroleum derived hydrocarbons (8 percent), and pesticides (5 percent). A comparison of monitoring data from sanitary landfills and secondary wastewater treatment plants suggests that the concentrations of heavy metal and organic pollutants discharged to surface waters from these two sources are similar.     

武汉市城市垃圾处理现状调查及展望

通过对近几年来武汉市城区生活垃圾的调查以及成分的分析,认为武汉市的生活垃圾以卫生填埋为主,有效控制填埋气体及渗滤液,并提出了城市垃圾的治理对策。     

抚顺市生活垃圾管理现状及对策探讨

文中系统分析了抚顺市固体废物的收运及处理现状。并对其对策进行了讨论。认为抚顺市应立足现实，完善固体废物管理体系；对固体废物分类收集。以源头控制为主，并逐步改进现有的较为单一的卫生填埋、堆放技术；尝试应用多种先进的综合处理新技术，改变传统的思维模式，加快固体废物处理市场化、产业化的步伐。走可持续发展之道路。