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901.
东辽河铁路大桥地基的第四系存在多原因形成的人为物质,构成桥桩基础施工的障碍,使桩孔钻探施工难以进行。经采用多种方法对不同问题进行处理,达到了施工目的。 相似文献
902.
Deep-well injection has been used to dispose of municipal liquid wastes in southwestern Florida since 1988. The liquid wastes
are injected into an extremely high-transmissivity zone of fractured dolomite in the Early Eocene Oldsmar Formation of the
Floridan aquifer system; this zone is commonly referred to as the Boulder Zone. Data collected during the drilling and operational
testing of southwestern Florida injection wells provide insights into the nature of the injection zone and overlying confining
beds. The location of high-transmissivity zones that are capable of accepting large quantities of waste water is vertically
and horizontally variable and cannot be predicted with certainty. A 40.9-m thick high-permeability interval in one injection
well, for example, was absent in a well drilled only 85.4 m away. Some upward migration of low-density injected fluids has
occurred, but at no site were the injected liquids detected in deep monitor wells, such as occurred at injection-well sites
along the coasts of southeastern, west-central, and east-central Florida. The primary confinement of the injected liquids
(i.e., deepest effective confining beds) consists of unfractured beds of low-permeability dolomite within the Oldsmar Formation,
whose locations are also laterally and vertically variable. The origin and controls of the distribution of fractures in the
Oldsmar Formation are poorly understood.
Received, December 1997 Revised, June 1998, August 1998 Accepted, August 1998 相似文献
903.
During stabilization or demobilization of contaminants in solid waste materials, different approaches can be taken, which also can be combined: (1) sufficient long-term buffer capacity can be provided, according to the environmental conditions; (2) permeability for dissolved contaminants can be reduced by secondary mineral precipitations or by soft gels injected into the pore space of the waste body; and (3) new formations of ‘reservoir minerals' can incorporate potential pollutants in their internal structure. Emphasizing the geochemical engineering approach, two examples are presented from the field of water management, both focussing on the demobilization of arsenic species. The first example (after Driehaus, W., 1994. Arsenentfernung mit Mangandioxid und Eisenhydroxid in der Trinkwasseraufbereitung. Vol. 133, Ser. 15, VDI-Reports, Düsseldorf, 117 pp.) relates to the problems during purification of arsenic-rich raw water, suggesting the potential application of iron and manganese oxide minerals as oxidizing agents and mineral lattice structures for the elimination of arsenic. In the second example, contaminated sludges from water treatment plants were investigated for their leaching characteristics and long-term stability. A pH-stat test procedure was used to assess the leaching characteristics of metals at typical pH values. Due to the presence of iron and manganese oxides pentavalent arsenic is protected against conversion into the mobile trivalent form at neutral to low pH. Experimental data suggest that co-disposal with reducing organic matter and alkaline stabilization material or wastes could negatively influence the binding properties and, therefore, should be avoided. 相似文献
904.
以地铁二号线浦东新区段杨高路车站围护结构的设计说明、施工方案及监测数据为依据,分析了地下连续墙作为围护结构在基坑开挖过程中的受力特点。 相似文献
905.
Integrated use of hydrochemistry and resistivity methods in groundwater contamination caused by a recently closed solid waste site 总被引:6,自引:0,他引:6
In order to investigate the groundwater contamination by solid waste disposal using both hydrochemical and geophysical methods,
the Halkalı (I˙stanbul) solid waste disposal site which was closed in 1994 was investigated. The disposal site lies on a ridge
between two valleys filled with alluvium. A total of six boreholes were drilled on two lines across the Menekşe valley adjacent
to the Halkalı site. Groundwater samples collected from these boreholes were analyzed for various contaminant parameters.
The results indicate that TDS and chloride concentrations decrease horizontally away from the waste site whereas they increase
with depth. Electrical soundings carried out at 12 locations yielded high resistivity values at the upstream part of Menekşe
valley while lower values were obtained from the locations near the leachate seepage points.
Received: 11 November 1997 · Accepted: 23 February 1998 相似文献
906.
分析环渤海在区域经济发展中的战略地位,北方大港群的建设是实现其战略地位的前提和保证,在对滦河三角洲沿岸大型港址群进行评价的基础上,提出分散组团式港群建设设想 相似文献
907.
由于长大隧道建设期间具有显著地集水廊道效应,施工过程中地下水不断向隧道轴线汇集,进而诱发一系列的水文
地质灾害,给施工人员和隧址区周边的生态环境带来不可估量的损失。为此,在构建山区公路隧道建设对地下水环境扰动
评价体系的基础上,考虑到群决策不同个体实践认知水平的差异,把基于决策人员偏好信息的区间数层次分析模型用于山
区公路隧道建设对地下水的环境影响评价领域,并与模糊综合评判法进行有机结合,对西藏米拉山特长隧道建设对地下水
环境影响进行评价,结果表明,米拉山特长公路隧道建设对地下水的扰动程度属于一般水平。依据评价结果,采取了相
应的工程措施,实现了隧道建设与隧址区环境保护的协调统一,可为类似地区隧道建设的地下水环评工作提供有益的
参考。 相似文献
908.
贵州黄磷渣的成分特征 总被引:16,自引:1,他引:16
本文讨论了贵州省粒状和块状黄磷渣的成分特征:①不同产地黄磷渣的化学组成均与天然硅灰石矿石的化学组成极为相似,主成分SiO2+CaO总量达86.74%~94.85%,有害元素含量较低。②块状黄磷渣由环硅灰石、枪晶石与两种自然界罕见的硅酸钙相(Ca8Si5O18和Ca2SiO4)共生。③原生粒状黄磷渣为非晶质体。通过加热实验和红外光谱分析、X射线衍射分析揭示粒状黄磷渣在加热过程中所发生的一系列物相演变。研究表明黄磷渣是一种很有利用前景的非金属矿物资源。 相似文献
909.
本文从矿产资源在国民经济建设中的重要性出发,根据九江市矿产资源的优势及其存在问题,向各级领导及决策部门提出了一重视、二协调、三加强、四提高、五兴办几项工作建议。 相似文献
910.
舟山深水港域开发建设的自然地质环境 总被引:2,自引:1,他引:2
本文从水深、水文、岸线、地貌及工程地质条件等诸方面阐述了中国舟山海域的自然地质环境, 说明了该港域具有建设大型深水港址的优越条件, 其开发建设将对中国东中部的经济发展具有重大意义。 相似文献