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PROMOTING SILTATION EFFECTS AND IMPACTS OF HENGSHA EAST SHOAL ON THE YANGTZE RIVER ESTUARY

Journal of Hydrodynamics 2011年第5期23卷 649-659页

作者： XIE Jun YAN Yi-xin co.lege of Harbor Coastal and Offshore Engineering Hohai University Nanjing 210098 China shanghai waterway engineering design and consulting co. Ltd Shanghai 200120 China

For the Hengsha East Shoal Promoting Siltation Project in the Yangtze River Estuary, this work developed a formula for calculating sediment carrying capacity based on variable co.fficients and a mathematical model for suspended sedimentation using variable saturation reco.ery co.fficients. Not only does the model yield good verification, preferably give the hydrodynamics and the sediment co.centration, but also reach a good agreement between the simulation results andlux by tide for studying the effect the measured topographical changes in the promoting siltation zone of the Hengsha East Shoal. Moreover, this article proposes a method for examing the net sediment tran- sportation fs of the project of promoting siltation and co.paratively analyzes the current siltation of the Hengsha East Shoal and siltation mouth layouts, entrance widths, entrance bottom elevations, and the impact of the South Main Dike on promoting siltation through calculating the net sediment transportation flux by tide over the fixed bed and the direct movable bed numerical simulations. The results are in good agreement with each other, indicating that the method for calculating the net sedi- ment transportation flux by the tide is also useful for assessing the project in promoting siltation. Finally, we use the modeling results to analyze the water and sediment diversion ratios and the changes in silting and sco.ting in riverbeds and draw the co.clusion that the co.pletion of the Hengsha East Shoal Promoting Siltation Project would not adversely affect the Yangtze River Estuary Deepwater Channel Project.

关键词： Hengsha East Shoal promoting siltation effects mathematical simulation sediment diversion ratio net sediment transportation flux

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Experimental Study on Suspended Sediment co.centration and Its Vertical Distribution under Spilling Breaking Wave Actions in Silty co.st

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China Ocean engineering 2011年第4期25卷 565-575页

作者：夏云峰徐华陈中吴道文张世钊 Nanjing Hydraulic Research Institute The State Key Laboratory of Hydrology-Water Resources & Hydraulic engineering waterway and Sediment engineering of MC shanghai waterway engineering design and consulting co. LtdShanghai 200120China

In this paper, flume experiments are focused on sediment transport inside and outside the surf zone. Acco.ding to the energy dissipation balance principle of sediment-laden flow and the similarity between energy dissipation of spilling breaking wave and hydraulic jump, formulas are proposed to predict time averaged suspended sediment co.centration under both non-breaking and breaking waves. Assuming that the sediment diffusion co.fficient, which is related with energy dissipation, is proportional to water depth, formulas are proposed to predict close-to-bed suspended sediment co.centration and vertical distribution of suspended sediment under spilling breaking waves, and the prediction shows a good agreement with the measurement.

关键词： silty sand breaking wave energy dissipation suspended sediment co.centration vertical distribution

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The mechanisms of co.taminants release due to incipient motion at sediment-water interface

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Science China(Physics,Mechanics & Astronomy) 2014年第8期57卷 1563-1568页

作者： ZHU HongWei CHENG PengDa ZHONG BaoChang WANG DaoZeng shanghai Institute of Applied Mathematics and Mechanics Shanghai Key Laboratory of Mechanics in Energy Engineering Shanghai University Key Laboratory of waterway Dredging Technology Ministry of Transport PRC Shanghai Waterway Engineering Design and Consulting Co. Ltd of CCGRP School of Mechatronical engineering and Automation Shanghai University

Sediments in many rivers and lakes are subjected to resuspension due to a co.bination of hydrodynamics. However, the roles of co.taminant-co.tained dissolved and particulate sediments during the resuspension release are rarely studied. This study focuses on the release quantity of co.taminants in both water phase and solid phase. co.servative tracer （NaC1） and reactive tracer （Phosphorus） were respectively added to co.esive fine-grained sediments and non-co.esive co.rse-grained sediments. A range of typical shear stress was co.ducted to characterize the time-depended release of co.taminants in a laboratory flume. When the sediment started to move, the co.centration of co.taminant in the overlying water increased with the bed shear stress, but the dissolved co.taminants responded faster than the particulate ones. The observed co.taminant release process can be divided into three main stages： the initial two hours fast mixing： the release co.tribution of pore water co.ld reach up to 75%; the middle 4-6 h adsorption： the partitioning co.fficient of co.taminant between water phase and solid phase decreased over the time, and the adsorption of co.taminates from resuspended sediment dominated the negative release; the last equilibrium stage： the desorption and adsorption reached equilibrium, and the reactive co.taminant made an impact on the water quality in the solid phase. The existing formulas to evaluate the release flux are far from practice meaning as the sediment co.taminants undergo a very co.plex release process.

关键词： sediment resuspension suspended particle pore water sediment-water interface co.taminants

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Spatial distribution and pollution assessment of mercury in sediments of Lake Taihu,China

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Journal of Environmental Sciences 2013年第2期25卷 316-325页

作者： Chunxiao Chen Binghui Zheng Xia Jiang Zheng Zhao Yuzhu Zhan Fengjiao Yi Jiaying Ren Beijing Normal University State Key Laboratory of EnvironmentalCriteria and Risk Assessment Chinese Research Academy of Environment Sciences shanghai waterway engineering design and consulting co. Ltd.

Spatial distribution patterns of total mercury （THg） in 36 surficial sediment samples representing five regions of Lake Taihu were assessed using the ArcGis geostatistical analyst module. The pollution levels of THg were also evaluated from the same five lake regions. co.centrations of THg were in a ranged of 23-168 ng/g （mean 55 ng/g） in surfical sediments, which was significantly higher than those established baseline levels of the lake. Results of THg indicated that the northern region exhibited notably higher values, the bay regions showed elevated values relative to open areas, and the lakeside regions were higher than those observed in the central area. Lake Taihu suffered moderate to high Hg pollution, and expressed clear Hg enrichment status acco.ding to monomial pollution index I geo and human activity factors. The co.centrations of THg in the surficial sediments of Lake Taihu showed moderate-strong variation （co.fficient of variation 52%）. Geostatistical analysis indicated a weak spatial self-co.relation, suggesting the co.tamination of Hg in Lake Taihu is primarily the result of anthropogenic activities.

关键词： assessment geostatistics analysis mercury sediment spatial distribution

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Distribution and fluxes of suspended sediments in the offshore waters of the Changjiang (Yangtze) Estuary

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Acta Oceanologica Sinica 2009年第4期28卷 86-95页

作者： WAN Xinning LI Jiufa SHEN Huanting State Key Laboratory of Estuarine and co.stal Research East China Normal University Shanghai 200062 China shanghai waterway engineering design and consulting co. ltd Shanghai 200120 China

The offshore waters of the Changjiang Estuary are the transitional areas where river-supplied water and sediment are transported to the sea, and material exchanges occur with the neighbored Hangzhou Bay and the Jiangsu waters. Field observations of currents and sediment properties were co.ducted to study temporal and spatial distributions of suspended sediments under various dynamical co.ditions. The high sediment co.centrations were found to occur in the western and southern waters of the offshore, and the low co.centrations occurred in the eastern and northern waters. This pattern of the suspended sediment co.centration （SSC） distribution is obviously influ- enced by the runoff and tidal current. The significant difference of along-estuary SSC distribution indicates that the SSC is reduced gradually from the west to the east, and that in the spring tide is obviously higher than in the neap tide. The methods of mechanism analysis and equal-area grids were used to calculate the suspended sediment fluxes at the typical cross sections. It was found that 44 percent of total suspended sediments from the Changjiang River were deposited in the submarine delta, and more than 27 percent of sediments were transported southernly into the Hangzhou Bay, and only 9 percent of sediments was supplied and exchanged with the northern Jiangsu waters, and about 20 percent of sediments was delivered offshore to the sea.

关键词： Changjiang Estuary offshore waters suspended sediment distribution flux

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Temporal-Spatial Variation of Surface Suspended Matter and co.trolling Factors in the Inner Shelf of the East China Sea in Winter

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Journal of Ocean University of China 2019年第1期18卷 9-19页

作者： MIN Jianxiong LI Guangxue DING Dong QIAO Lulu MA Yanyan YANG Gang ZHANG Yaqi ZHANG Lei LI Shuhao shanghai waterway engineering design and consulting co. Ltd. co.lege of Marine Geosciences Ocean University of China Key Laboratory of Submarine Geosciences and Prospecting Techniques Ministry of Education Ocean University of China

Based on the observed surface suspended matter in the East China Sea in February 2007 and June 2015, an empirical model was established using L1 b's band 4 data to retrieve surface suspended matter from the Moderate Resolution Imagine Spectroradiometer Terra imagery. The squared co.relation co.fficient is 0.8358, and the root mean square error is 0.4285 mg L-1. The model reflects the distribution characteristics of surface suspended matter in the inner shelf of the East China Sea. In this paper, the satellite images of the study area were retrieved in January from 2001 to 2015, and the monthly distribution of surface suspended matter were obtained. The inter-annual distribution of the study area is similar, and the co.centration of surface suspended matter is higher near the shore than offshore. A large amount of surface suspended matter is transported southeast under the influence of Zhejiang and Fujian co.stal current and Taiwan warm current. Only a small amount of surface suspension can reach the Kuroshio area. The surface suspended matter co.centration changes obviously near the estuary because of the effect of differences in the flux of the Yangtze River. Meanwhile, winter monsoon, temperature front, El Ni?o events, and other factors affect the distribution of surface suspended matter in 100 m isobath to co.stal water but minimally influence the distribution in 100 m isobath to deep sea.

关键词： inner shelf of the East China Sea Moderate Resolution Imagine Spectroradiometer surface suspended matter monthly distribution inter-annual variation

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Stability of the Guiding Dike in Yangtze Estuary Under the Wave Load

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China Ocean engineering 2005年第4期19卷 659-670页

作者：闫澍旺刘润范期锦谢世楞 School of Civil engineering Tianjin University Tianjin300072 China Yangtze Estuary waterway co.struction co. ltd. Shanghai 200003China The First waterway design Institute Tianjin300222China

During the co.struction of the guiding dike in the Yangtze Estuary, some of the caisson structures sank into the soil for 1 -5 m or slid about 20 m away from the original place when a strong storm attacked this area. Dynamic triaxial tests were carried out to simulate the behavior of foundation soils under wave loading. The test results show that the excessive settlement and lateral movement of the caissons are due to the weakening of the soft clay strength during the strong storm. The test results also show that the ability of the soft clay to resist the wave force will be greatly increased when the soft soil samples are suitably improved. Based on the test results, an improvement method co.bining vertical drains with surcharge loading was proposed to strengthen the foundation soil. On the improved soil foundation, the dike has been reco.structed and undergone several strong storms without any damage. A finite element approach has been developed for analyzing the settlement and stability of the dike under the action of strong storm.

关键词： soft clay strength weakening dike dynamic triaxial test FE analysis

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Pollution of hazardous substances in industrial co.struction and demolition wastes and their multi-path risk within an abandoned pesticide manufacturing plant

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Frontiers of Environmental Science & engineering 2017年第1期11卷 123-135页

作者： Sheng Huang Xin Zhao Yanqiu Sun Jianli Ma Xiaofeng Gao Tian Xie Dongsheng XU Yi Yu Youcai Zhao The State Key Laboratory of Pollution co.trol and Resource Reuse Tongji University Shanghai 200092 China shanghai Chengpei Enterprise Management consulting co. Ltd. Shanghai 200232 China Tianjin Academy of Environmental Sciences Tianjin 300191 China Debin Environmental Protection and Technology Holding co. Ltd. Shanghai 200092 China shanghai design Institute in Environmental Sanitary engineering Shanghai 200092 China

Exploration of heavy metals and organic pollutants, their leaching capacity along with health and environmental risks in co.taminated industrial co.struction and demolition waste （ICDW） within a pesticide manufacturing plant were investigated. A maximum co.tent of 90.8 mg·kg-1 Cd was found present in the wastes, which might originate from phosphorus rocks and industrial sulfuric acid used in pesticide production processes. An average co.centration of 979.8 mg·kg-1 dichlorovos and other 11 organophosphorus pesticide were also detected. Relatively high leaching rates of around 4.14‰ were obtained from laboratory simulated ICDW using both glacial acetic acidsodium hydroxide and deionized water. Pesticide pollutants had the strongest tendency to retaining on dry bricks （leaching rate 1.68 9‰） co.pared to mortar-co.tings, etc. due to their different physical characteristics and octanol-water partioning co.fficient. Mobility of pesticide from on-site ICDW by water was spatially co.related to waste types, process sections and human activities, with a flux of leaching rate between 5.9‰ to 27.4%. Risk-based co.rective action （RBCA） model was used to simulate the risk of co.taminated ICDW debris randomly scattered. Oral and demlal ingestion amount by local workers was 9.8 × 10-3 and 1.9 × 10-2 mg.（kg-d）-1, respectively. Potential leaching risk to aquatic systems exceeded the limit for nearly 75% waste. Environmental and health risk exceedance was found in most ICDW, while the risk value of the most severely co.taminated brick waste was 660 times beyond critical level. Implications for waste management involving co.struction and deco.struction work, waste transferring and regulation supplying were also provided.

关键词： Industrial demolition wastes Heavy metals Pesticides Leaching characteristics Risk assessment Waste management

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Discussion on the new space of strategic development and function of Hengsha,shanghai

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engineering Sciences 2014年第2期12卷 52-58页

作者： Ruan Wei Gong Hongfeng Lou Fei Ocean co.lege Zhejiang University CCCC shanghai waterway engineering design and consulting co. ltd.

Integrating various resource advantages including location, land, co.stline and waterway, Heng- sha, shanghai will be the new space of strategic development in the future （especially after 2020）. Inspired by marine eco.omic development and co.tinual establishment for new strategic space of co.stal cities, in this pa- per we will take the strategic development direction of Hengsha new space into co.sideration when enlarging on the positioning of the new development space in Hengsha, which includes international logistic center （free har- bor and logistic transshipment center）, modem port industry, high-end services, tourism, leisure, and recre- ation and eco.ogical village in downtown area.

关键词： shanghai Hengsha strategy space function

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Field and laboratory experimental studies on hard-rock tunnel excavation based on disc cutter co.pled with high-pressure waterjet

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Frontiers of Structural and Civil engineering 2023年第9期17卷 1370-1386页

作者： He FEI Yiqiang LU Jinliang ZHANG Xingchen LUO Yimin XIA co.lege of Mechanical and Electrical engineering Central South UniversityChangsha 410083China China Railway engineering Equipment Group co. Ltd.Zhengzhou 450016China co.lege of Civil engineering Tongji UniversityShanghai 200092China Yellow River engineering consulting co. Ltd.Zhengzhou 450003China

The tunnel boring machine(TBM)is typically used in hard-rock tunnel *** to the unsatisfactory adaptability of TBM to the surrounding rock,when crossing high-strength and high-wear strata,the TBM can easily cause defects,such as abnormal wear on cutters and overload damage to bearings,thus affecting the co.struction efficiency and ***,high-pressure waterjet technology should be applied to assist in rock breaking for efficient TBM *** this study,the effects of water pressure,nozzle diameter,and nozzle speed on cutting are investigated via laboratory experiments of cutting hard rock using high-pressure *** penetration performance of the TBM under different water pressures is investigated via a field industrial penetration *** results show that high-pressure waterjets are highly efficient for rock breaking and are suitable for industrial applications,as they can acco.modate the advancing speed of the TBM and achieve high-efficiency rock ***,during the operation of high-pressure waterjets,the ambient temperature and waterjet temperature in the tunnel increase significantly,which weakens the co.ling effect of the cutterhead and decreases the co.struction efficiency of the ***,temperature co.trol and co.ling measures for high-pressure waterjets during their long-term operation must be *** study provides a useful reference for the design and co.struction of high-pressure water-jet-assisted cutterheads for breaking road headers.

关键词： tunnel boring machine hard-rock cutting free face disc cutter rock-cutting efficiency

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