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上下川岛地貌考察

热带地理 1986年第2期6卷 153-157页

作者：林晓东广州地理研究所

台山县的上川岛、下川岛是粤西沿海的两大岛屿,地理座标前者21°34′—21°47′N,112°42′—112°52′E;后者21°35′—21°43′N,112°31′—112°40′E(图1);面积分别为156.7和86.9平方公里。1985年初,笔者参加了上下岛综合考察,兹... 详细信息

台山县的上川岛、下川岛是粤西沿海的两大岛屿,地理座标前者21°34′—21°47′N,112°42′—112°52′E;后者21°35′—21°43′N,112°31′—112°40′E(图1);面积分别为156.7和86.9平方公里。1985年初,笔者参加了上下岛综合考察,兹将踏勘所得地貌资料简述如下.

关键词：下川岛变质岩上川岛地貌地形

Performance of a deep excavation and the influence on adjacent piles:A case history in karst region covered by clay and sand

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Underground Space 2023年第1期8卷 45-60页

作者： Yubing Yang Caiyuan Chen Chao Liu Longtian Huang Wei Chen Nengyou lin Jie Cui Wandong Xie College of Water Conservancy and Civil Engineering South China Agricultural UniversityGuangzhou 510642PR China School of Civil Engineering Guangzhou UniversityGuangzhou 510006PR China Architectural Design and Research institute of guangdong province Guangzhou 510010PR China CCCC–FHDI Engineering Co. LtdGuangzhou 510290PR China

This paper presents a case study of deep excavation adjacent to an existing bridge in karst region of guangzhou city,*** movements of retaining structures,settlements of surrounding ground and pipelines,and the responses of bridge piles were measured and evaluated.A sudden surge of groundwater was recorded at the north pit when excavated ***-cement columns using the Metro Jet System(MJS)method was employed along the outer perimeters of the diaphragm wall where water inflow occurred,for the sake of blocking the flow *** measured maximum wall deflection dhm in this case ranged from 0.13%H to 0.3%H,with a mean value of 0.2%H(H is the excavation depth),which agreed well with the empirical prediction in mixed *** the MJS treatment,the wall and surrounding soils experienced notable lateral deflection and *** bridge piles experienced significant settlement since the excavation commenced,which might be attributed to the inherent deficiency in geological condition and pile *** soil disturbance induced by the adjacent deep excavation accelerated bridge *** finite element analysis revealed that the excessive settlement of the bridge piles and ground surface resulted from confined-water withdrawal in sand layers.

关键词： Deep excavation MJS treatment Pile-foundation Karst region Confined-water

Risk assessment of heavy metals in topsoil along the banks of theYangtze River in Huangshi, China

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Journal of Groundwater Science and Engineering 2017年第2期5卷 162-172页

作者： lin Dan JIN Meng-gui LI Xiu-juan College of Civil Engineering and Architecture Zhejiang University Hangzhou 310058 China Laboratory of Basin Hydrology and Wetland Eco-restoration & School of Environmental Studies China University of Geosciences Wuhan 430074 China Zhejiang institute of Geology and mineral Resources Hangzhou 310007 China guangdong province geological Environmental Monitoring Station Guangzhou 510510 China

High concentrations of heavy metal in farmland threatens food production and human health. Our study assesses soil quality and the distribution of Cd, Cr, Cu, Zn, Pb and Ni, to identify possible sources of heavy metals along the banks of the Yangtze River in Huangshi. Heavy metal concentrations of 22 topsoil samples were measured using the inductively coupled plasma mass spectrometry instrument and data was analyzed by multivariate statistic approaches. Heavy metal contamination risk assessment was performed using a combination of the Nemerow multi-factor index method, the Hakanson potential ecological risk index method and the Muller index of geo-accumulation method. These methods determined similar results indicating that cadmium(Cd) poses a health risk to residents at the study site while Cr, Cu, Zn, Pb and Ni do not. The Nemerow multi-factor index method demonstrated that 18 samples were heavily polluted, three moderately polluted and one lightly polluted. The Muller index of geo-accumulation method found ten samples were moderately to strongly polluted by Cd, five were moderately polluted, six were lightly to moderately polluted and one was lightly polluted. The Hakanson potential ecological risk index method proved six samples were strongly polluted, seven were moderately polluted and nine were lightly polluted. Since our sampling sites were all in agricultural lands, we recommend the potential ecological risk index method as the most effective given it not only considers the range of pollutants contributing to soil pollution but factors in heavy metals toxicity. We are apt that the source of the high concentrations of Cd found in topsoil is derived from alluvial sediments upstream of the Yangtze River with a high percentage of residual speciation and a low percentage of exchangeable speciation distribution of Cd. This in turns indicates that a high concentration of Cd in soil had little impact on the natural environment. However, 31.9% of the iron-manganese o

关键词： Heavy metals Risk assessment Soil chemical analysis The Yangtze River Huangshi

复杂条件下的深基坑支护设计选型研究及实例分析

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广东土木与建筑 2018年第1期25卷 1-3,35页

作者：谢琳广东省建筑设计研究院广州510010

针对复杂地质的岩土工程特性,从竖向支护和侧向支护体系系统分析和详细介绍了在此类地区深基坑支护设计方案选型;同时针对复杂条件下某深基坑支护工程案例,通过数值计算和监测结果的对比分析,得出一些有价值的结论,为深基坑的设计与稳... 详细信息

针对复杂地质的岩土工程特性,从竖向支护和侧向支护体系系统分析和详细介绍了在此类地区深基坑支护设计方案选型;同时针对复杂条件下某深基坑支护工程案例,通过数值计算和监测结果的对比分析,得出一些有价值的结论,为深基坑的设计与稳定性控制提供理论指导,从而为类似工程设计和施工提供参考。

关键词：复杂地质深基坑支护竖向体系侧向体系

福建闽江口—三沙湾口近岸海域沙波群发育特征、成因及其对海洋工程应用的影响

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中国地质 2020年第5期47卷 1554-1566页

作者：伊善堂吴承强林纪江胡小三罗伟东中国地质调查局广州海洋地质调查局广东广州510075 自然资源部海底矿产资源重点实验室广东广州510075 自然资源部第三海洋研究所福建厦门361005 国家海洋局南海信息中心广东广州510310

基于高精度多波束、单波束、侧扫声呐等资料研究发现,福建近岸闽江口和三沙湾口外海域分别发育一处海底沙波群。本文详细分析了海底沙波地貌发育特征,根据沙波发育形态及沙脊线走向将其分为挠曲型沙波、直线型沙波和过渡型沙波3类。调查... 详细信息

基于高精度多波束、单波束、侧扫声呐等资料研究发现,福建近岸闽江口和三沙湾口外海域分别发育一处海底沙波群。本文详细分析了海底沙波地貌发育特征,根据沙波发育形态及沙脊线走向将其分为挠曲型沙波、直线型沙波和过渡型沙波3类。调查区2处沙波群均呈迎潮面坡度缓而背潮面陡的特征,沙波末端均存在分枝并伴随着一定程度的弯曲变形。沉积物质来源和水文动力环境是控制海底沙波群发育的两个主要因素,研究区近岸基岩侵蚀物质、河流沉积物质和洋流输运物质来源减少打破了维持沙波动态平衡的物质供应,底流冲刷提供了海底泥沙的起动条件。结合沙波纹、残留沙丘及海底沙波的发育特征,本文认为沙波存在一定的活动性,具有向坡陡一侧不断迁移的规律。最后,通过对沙波活动性成因和演化规律进行分析,并详细探讨了海底沙波的存在对海洋工程应用的影响,提出了相应的防范措施,为近岸海底工程建设及灾害预防提供了一定的借鉴意义。

关键词：近岸海域沙波群地貌特征控制因素起动流速海洋地质调查工程闽江口三沙湾口福建

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关于矿产资源储量统计工作的思考

资源环境与工程 2020年第2期34卷 303-306页

作者：雷霖王卉胡君杨培阮志桥湖北省地质科学研究院湖北武汉430034 湖北省郧西县自然资源和规划局湖北十堰442600 广东省矿产资源储量评审中心广东广州510000 湖北省地质局第八地质大队湖北襄阳442000

矿产资源储量统计工作是管理国家矿产资源账户的重要手段,是一项年度性的矿政管理工作。从介绍湖北省矿产资源储量统计工作基本做法入手,分析在当前形势下,资源储量统计工作中所面临的未能统计湖北省全部查明资源家底、统计精细度不够... 详细信息

矿产资源储量统计工作是管理国家矿产资源账户的重要手段,是一项年度性的矿政管理工作。从介绍湖北省矿产资源储量统计工作基本做法入手,分析在当前形势下,资源储量统计工作中所面临的未能统计湖北省全部查明资源家底、统计精细度不够、专项调查成果与矿产资源储量数据库未有效衔接、矿山年报质量不高等多项问题。为解决上述问题,从管理、机制、规则、系统、人员等方面进行系统分析研究,提出在完善管理制度、规范统计管理规则、做好专项调查的对接机制、增强信息化建设等建议与措施。

关键词：矿产资源储量管理储量统计