首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 500 毫秒
1.
蒋中明  钟兵  万发 《岩土工程学报》2023,(12):2529-2536
水封石油洞库储油可能造成地下水污染。明晰石油污染物在裂隙岩体中的运移规律是库区地下水污染防控的前提。为揭示石油污染物在洞周围岩地下水中的运移规律,基于裂隙-孔隙双重介质模型,采用数值模拟方法研究了石油中的特征污染物——苯的运移扩散过程,并分析了裂隙倾角、裂隙开度、基质渗透率和纵向弥散度对苯运移规律的影响。研究表明:储库正常运行50 a后,苯的迁移被限制在较小的范围内,不会到达水幕系统,也不会进入到地面表层下的水体中。在长期运行条件下,相邻洞周围岩中的污染晕可相互连通,并将引起相邻洞罐中油品污染物之间的交叉污染。苯的竖向污染距离对纵向弥散度和裂隙倾角大小敏感性强,而对裂隙开度和基质渗透率的敏感性较弱。洞室间岩柱中轴线上苯的最大浓度对裂隙倾角最为敏感,且随裂隙倾角和基质渗透率的增大而减小,随纵向弥散度和裂隙开度的增加而增大。  相似文献   

2.
城市生活垃圾淋滤液运移模型问题   总被引:20,自引:0,他引:20  
本文通过对淋滤液运移模型的研究,给出了多孔介质和双重介质淋滤液运移模型的定解问题,采用广义迎风格式求解淋滤液运移模型,消除数值弥散。运用模型预测垃圾填埋场污染晕,为防治地下水污染提供依据。  相似文献   

3.
邱建强 《矿产勘查》2023,14(7):1244-1249
本文利用地下水数值模拟软件GMS,研究矿石淋滤水对地下水污染的影响。模拟在非正常状况下,矿石经雨水淋滤后,淋滤液中的污染物直接穿透包气带进入地下水运移的情景。经预测,泄漏的污染物铁经过运移后出现短暂超标现象,超标范围未出研究区范围,没有对下游敏感点造成影响。随着时间的推移,污染物在地下水的对流、弥散作用下,污染晕中心浓度逐渐降低,污染晕范围逐渐扩大,直至低于限值。研究成果可为该区的地下水保护措施提供依据。  相似文献   

4.
低渗透污染土水动力弥散参数试验研究   总被引:1,自引:0,他引:1  
李磊  朱伟  屈阳  包建平 《岩土工程学报》2011,33(8):1308-1312
污染土的治理中通常采用降低渗透性的措施来控制其二次污染。通过获得其水动力弥散参数可以对其二次污染进行评价和预测,但是现有的土柱试验以及求解方法不适用于低渗透污染土水动力弥散参数的测定和求解。针对低渗透污染土水动力弥散参数试验和求解的问题,提出采用改进的柔性壁渗透仪测定其污染物的穿透曲线,根据所获得的穿透曲线,采用数值反演的方法计算污染土的水动力弥散参数。结果表明,采用柔性壁渗透仪和数值反演的方法,能够满足低渗透污染土水动力弥散参数测定的需要。  相似文献   

5.
地下水动力弥散参数,对预测和控制地下水污染具有重要意义。通过弥散试验,能求出它们的方法有多种,可均要知道地下水流向。从分析地下水流向与观测井可能空间关系的基础上,结合观测井浓度的变化,本文给出图解分析法。用实例进行了验证,经比较,其结果可信。  相似文献   

6.
地下水流与水质联合数值模拟应用研究   总被引:1,自引:0,他引:1  
随着社会的不断发展,工业、农业和人类生活中的废弃物很多,特别是城市工业废水的大量排放,农药化肥的广泛应用,致使许多地区的地下水受到不同程度的污染。基于水动力弥散的水质模型,采用多单元均衡法(MEB),利用VC++语言编写地下水流与水质数值模拟联合通用程序,实现程序可视化。结合实际算例,利用该程序对地下水流与水质的输运机理进行数值模拟研究,发现该程序人机对话良好,可操控性高;为地下水资源的合理开发、保护和利用进行数值模拟提供了依据。  相似文献   

7.
环境影响评价项目多数都要对地下水做专项调查报告,野外弥散试验又是地下水专项调查报告的核心。文章以周口隆达发电有限公司扩建工程地下水专项调查项目的野外弥散试验为依据,确定了地下水含水层的弥散参数,为准确可靠的地下水污染预测模型提供依据。对地下水环境影响评价具有实际意义。  相似文献   

8.
《Planning》2014,(24)
本文从对流作用、分子扩散和机械弥散作用三方面论述了污染物在地下水中的迁移机制,通过对地下水中水动力弥散尺度效应研究成果的总结和分析,阐述了纵向弥散度与尺度的关系,为地下水污染模型研究提供了一种参数的初步估计。  相似文献   

9.
电化学法去除地下水中的铬   总被引:1,自引:0,他引:1  
电化学法去除地下水中的铬工业区地下水常被铬污染,地下水中铬浓度超标。例如美国新泽西州一些工业区地下水中含铬10~26mg/L,个别地区高达60mg/L。以前用离子交换法处理,即用阳离子交换树脂先去除3价铬,再用阴离子交换树脂去除6价铬(CrO4、Cr...  相似文献   

10.
二氧化氯在石油污染地下水治理中的应用   总被引:10,自引:0,他引:10  
在治理被污染的地下水时,必须对污染源的土壤、包气带和包水带同时治理。土壤或包气带可以通过焚烧、化学氧化及生物作用加以处理;包水带可以通过水力截获、氧化曝气、生物降解以及化学氧化进行治理,但若单纯使用上述任何一种方法很难使地下水恢复水质。通过氯同位素分析三氯乙烯(TCE)在含水层中的自然降解可知,在包气带TCE经过几年后已有部分降解,而在包水带几乎不存在自然降解[1]。在包水带净化这一领域,国内外学者还未达成共识[2~4]。目前国内地下水污染防治工作仅限于对污染状况的检测和评价,西欧、北美等地区的…  相似文献   

11.
Installation of temporary or long term monitoring sites is expensive, so it is important to rationally identify potential locations that will achieve the requirements of regional air quality management strategies. A simple, but effective, numerical approach to selecting ambient particulate matter (PM) monitoring site locations has therefore been developed using the MM5-CAMx4 air pollution dispersion modelling system. A new method, ‘site efficiency,’ was developed to assess the ability of any monitoring site to provide peak ambient air pollution concentrations that are representative of the urban area. ‘Site efficiency’ varies from 0 to 100%, with the latter representing the most representative site location for monitoring peak PM concentrations. Four heavy pollution episodes in Christchurch (New Zealand) during winter 2005, representing 4 different aerosol dispersion patterns, were used to develop and test this site assessment technique. Evaluation of the efficiency of monitoring sites was undertaken for night and morning aerosol peaks for 4 different particulate material (PM) spatial patterns. The results demonstrate that the existing long term monitoring site at Coles Place is quite well located, with a site efficiency value of 57.8%. A temporary ambient PM monitoring site (operating during winter 2006) showed a lower ability to capture night and morning peak aerosol concentrations. Evaluation of multiple site locations used during an extensive field campaign in Christchurch (New Zealand) in 2000 indicated that the maximum efficiency achieved by any site in the city would be 60-65%, while the efficiency of a virtual background site is calculated to be about 7%. This method of assessing the appropriateness of any potential monitoring site can be used to optimize monitoring site locations for any air pollution measurement programme.  相似文献   

12.
介绍了城市街道峡谷内污染物的特点和扩散模式,分析了换气效率、室内气流组织、污染物扩散方式等影响建筑自然通风的主要因素,并对实地测量法和数值模拟法进行了分析和比较。  相似文献   

13.
P. Kahlig 《Water research》1979,13(12):1311-1316
Using an exact solution of Taylor's dispersion equation (including forced convection and a first-order removal process), a new routing procedure for short-term prediction of downstream pollution is derived, and is compared to H. B. Fischer's well-known method. An interaction between the dispersion and removal processes is demonstrated, and its usual neglection in river dispersion problems is justified.  相似文献   

14.
Traffic‐related air pollution is a serious problem with significant health impacts in both urban and suburban environments. Despite an increased realization of the negative impacts of air pollution, assessing individuals' exposure to traffic‐related air pollution remains a challenge. Obtaining high‐resolution estimates are difficult due to the spatial and temporal variability of emissions, the dependence on local atmospheric conditions, and the lack of monitoring infrastructure. This presents a significant hurdle to identifying pollution concentration hot spots and understanding the emission sources responsible for these hot spots, which in turn makes it difficult to reduce the uncertainty of health risk estimates for communities and to develop policies that mitigate these risks. We present a novel air pollution estimation method that models the highway traffic state, highway traffic‐induced air pollution emissions, and pollution dispersion, and describe a prototype implementation for the San Francisco Bay Area. Our model is based on the availability of real‐time traffic estimates on highways, which we obtain using a traffic dynamics model and an estimation algorithm that augments real‐time data from both fixed sensors and probe vehicles. These traffic estimates combined with local weather conditions are used as inputs to an emission model that estimates pollutant levels for multiple gases and particulates in real‐time. Finally, a dispersion model is used to assess the spread of these pollutants away from the highway source. Maps generated using the output of the dispersion model allow users to easily analyze the evolution of individual pollutants over time, and provides transportation engineers and public health officials with valuable information that can be used to minimize health risks.  相似文献   

15.
余兴  徐长春  莫远昌 《山西建筑》2011,37(33):64-66
采用梁柱法和稳定函数推导了梁柱结构考虑二阶效应及梁柱半刚性连接时的单元刚度矩阵,并用Kishi-Chen幂函数模型描述了半刚性连接的特性,采用B样条函数及正交多项式乘积的线性组合,构造了QR法的结构整体位移函数,通过QR法样条离散,建立起QR法的计算格式,并编制了相应的计算程序。  相似文献   

16.
As cities grow, automobile exhaust pollution is worsening, which has become a major problem of air pollution, even it is a serious threat to the physical and mental health of residents. Thus, to study its diffusion law and influential factors occupies a count for much position. The paper analyzes the factors that affect the dispersion of urban vehicle emissions in street canyon to evaluate the research method of pollutant dispersion. In addition, the influences of different wind speeds and wind directions, the roof shape of buildings on both street sides, and the relative height of the two sides of buildings on the street canyon, on airflow field and pollutant dispersion are simulated. It is shown that the wind speed, the wind direction and the buildings on both sides have a great impact on the airflow and contaminant dispersion in the street canyon. The results provide scientific basis for controlling, monitoring and evaluating the urban motor vehicle emissions, besides the reasonable layout and the programme of urban streets.  相似文献   

17.
主要采用样条有限点法分析箱梁剪力滞,并结合试验比较了样条有限点法和有限元法分析箱梁剪切滞的结果,表明采用样条有限点法分析箱型结构简洁有效。  相似文献   

18.
根据罚单元的概念以非等距B3样条为基函数建立了样条罚子域,有效地解决了组合旋转壳结构中非光滑连接子城位移协调问题.拓宽了样条子域法的应用范围.对于一般区域及光滑连接部分则一律采用广义样条子域法建立位移模式.算例表明,利用该方法进行组合旋转壳分析,具有自由度少,精度高和便于程序实现的特点.  相似文献   

19.
工程岩体抗剪强度确定综合方法——GMEM研究   总被引:6,自引:4,他引:6  
工程岩体的强度由于受到岩性、节理、地下水、温度场等的影响导致其强度的确定成为岩石力学界的一个重大难题。工程岩体具有地质、力学和工程3大特色,其强度的确定也应综合考虑这3种因素。在此基础上,提出利用经验类比、岩体质量评分体系和连通率的方法结合宏观地质条件判断结果综合确定工程岩体强度的方法——GMEM(geology,mechanics and engineering memod)。运用该方法在向家坝等许多工程中得到很好的应用。  相似文献   

20.
地下水对深圳某深基坑工程的影响   总被引:1,自引:0,他引:1  
陈静  李迎新 《土工基础》2005,19(2):22-23
在分析深圳地区地质条件及自然因素的条件下,运用某酒店基坑支护作为实例,对地下水影响因素进行论述。并提出在基坑中对地下水及地表水进行预防。  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号