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Long-term settlement behavior of ground around shield tunnel due to leakage of water in soft deposit of Shanghai

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Frontiers of Structural and Civil engineering 2011年第2期5卷 194-198页

作者： Huaina WU Yeshuang XU Shui-long SHEN Jin-chun CHAI state key laboratory of ocean engineering and Department of Civil Ergineering Shanghai Jiao Tong UniversityShanghai 200240China Department of Civil engineering Saga UniversitySaga 840-8502Japan

The lining of shield tunnel is usually composed of segments,in which the joints,cracks,and the grouting holes(hereafter called lining deficit)*** the long-term running,soils and groundwater may leak from these kinds of lining *** leaking of soil and groundwater causes the long-term ground loss around tunnel and thus results in the settlement of ground *** paper aims to analyze the impact of the leakage of groundwater through segments on the long-term settlement of ground *** adopted analytical method is based on the theory of groundwater seepage by using numerical *** analyzed results show that settlement of ground surface increases gradually with the increase of the leaked volume of tunnel *** the leaked volume was unevenly distributed,differential settlement occurred *** analysis by changing the leaked volume was *** results reveal that there is a linear relationship between settlement and leaked volume when the leaked volume was controlled within the allowable limit.

关键词： lining deficit leakage of water shield tunnel settlement soft deposit

Three-dimensional characteristics of mesoscale eddies simulated by a regional model in the northwestern Pacific ocean during 2000–2008

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Acta oceanologica Sinica 2022年第10期41卷 74-93页

作者： Guijing Yang Xiayan Lin Guoqing Han Yu Liu Gengxin Chen Jianhui Wang Marine Science and Technology College Zhejiang Ocean UniversityZhoushan316000China state key laboratory of Satellite ocean Environment Dynamics Second Institute of OceanographyMinistry of Natural ResourcesHangzhou310012China Southern Marine Science and engineering Guangdong laboratory(Zhuhai) Zhuhai519082China state key laboratory of Tropical oceanography South China Sea Institute of OceanologyChinese Academy of SciencesGuangzhou510301China

Mesoscale eddies play vital roles in ocean *** previous studies focused on eddy surface features and individual three-dimensional(3D)eddy cases in the northwestern Pacific ocean,the analysis of unique eddy3D regional characteristics is still lacking.A 3D eddy detection scheme is applied to 9 years(2000-2008)of eddyresolving Regional ocean Modeling System(ROMS)output to obtain a 3D eddy dataset from the surface to a depth of 1000 m in the northwestern Pacific ocean(15°-35°N,120°-145°E).The 3D characteristics of mesoscale eddies are analyzed in two regions,namely,Box1(Subtropical Countercurrent,15°-25°N,120°-145°E)and Box2(Southern Kuroshio Extension,25°-35°N,120°-145°E).In Box1,the current is characterized by strong vertical shear and weak horizontal *** Box2,the current is characterized by the strong Kuroshio,topographic effect,and the westward propagation of Rossby *** results indicate the importance of baroclinic instability in Box1,whereas in Box2,both the barotropic and baroclinic instability are ***,the mesoscale eddies’properties in Box1 and Box2 are *** eddies in Box1 have larger number and radius but a shorter *** contrast,Box2 has fewer eddies,which have smaller radius but longer ***,more eddies are detected at the subsurface than at the surface in both regions;the depth of 650 m is the turning point in *** this depth,the number of cyclonic eddies(CEs)is larger than that of anticyclonic eddies(AEs).In Box2,the number of CEs is dominant *** kinetic energy(EKE)and mean normalized relative vorticity in Box2are significantly higher than those in *** increasing depth,the attenuation trend of EKE and relative vorticity of Box1 become greater than those of ***,the upper ocean(about 300 m in depth)contains 68.6%of the eddies(instantaneous eddy).Only 16.6%of the eddies extend to 1000 *** addition,about87%of the eddies are bowl-shaped eddies in the two reg

关键词： three-dimensional structures mesoscale eddies northwestern Pacific ocean

Design of Drive and Control System for "Bird"

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Design of Drive and Control System for "Bird"

刚性圆柱结构顺流向涡激振动特性分析(英文)

2012年计算机应用与系统建模国际会议

作者： Xiaoqing Zhang Weijing Zhang state key laboratory Of ocean engineering Shanghai Jiaotong University

In order to control the rotation of hydrofoils of "bird", further to control the position and orientation of marine seismic streamers, a design solution for drive and control system is provided in this paper. Worm Gear Drive mechanism is used as transmission mechanism, some sensors and intelligent meters are chosen to implement the data collection and communications. By using the configuration software of Kingview to realize the real-time monitoring. A test is carried out to testify the solution, the results of the test shows that the solution can meet the require of control for bird. But also some deficiencies need to be improved.

关键词： Bird Marine seismic streamers Hydrofoil

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船舶力学 2012年第9期16卷 1035-1040页

作者：徐万海吴应湘胡松涛杜杰天津大学水利工程仿真与安全国家重点实验室天津300072 中国科学院力学研究所水动力学与海洋工程重点实验室北京100190 新兴重工集团有限公司北京100070

文章研究了刚性支承圆柱的顺流向涡激振动特性,在第二激励区域,运用van der Pol方程描述漩涡脱落的尾迹特性,采用尾流振子模型计算圆柱结构的响应,讨论和分析了质量-阻尼参数、质量率和结构阻尼对顺流向涡激振动的影响机理。

关键词：顺流向涡激振动圆柱尾流振子模型质量-阻尼参数

Discovering the roles of subsurface microorganisms: Progress and future of deep biosphere investigation

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Chinese Science Bulletin 2013年第4期58卷 456-467页

作者： WANG FengPing LU ShuLin ORCUTT Beth N XIE Wei CHEN Ying XIAO Xiang EDWARDS Katrina J state key laboratory of Microbial Metabolism and state key laboratory of ocean engineering Shanghai Jiao Tong University key laboratory of Systems Biomedicine Ministry of Education Shanghai Jiao Tong University Center for Geomicrobiology Aarhus University Bigelow laboratory for ocean Sciences 60 Bigelow Drive School of ocean and Earth Sciences Tongji University The University of Southern California Departments of Biological & Earth Sciences

The discovery of the marine "deep biosphere"-microorganisms living deep below the seafloor-is one of the most significant and exciting discoveries since the ocean drilling program began more than 40 years ago. Study of the deep biosphere has become a research frontier and a hot spot both for geological and biological sciences. Here, we introduce the history of the discovery of the deep biosphere, and then we describe the types of environments for life below the seafloor, the energy sources for the living creatures, the diversity of organisms within the deep biosphere, and the new tools and technologies used in this research field. We will highlight several recently completed Integrated ocean Drilling Program Expeditions, which targeted the subseafloor deep biosphere within the crust and sediments. Finally, future research directions and challenges of deep biosphere investigation towards uncovering the roles of subsurface microorganisms will be briefly addressed.

关键词：深部生物圈地下微生物综合大洋钻探计划深海底生物科学多样性沉积物海洋

Exact free vibration analysis of open circular cylindrical shells by the method of reverberation-ray matrix

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Journal of Zhejiang University-Science A(Applied Physics & engineering) 2016年第4期17卷 295-316页

作者： Xiong-liang YAO Dong TANG Fu-zhen PANG Shuo LI College of Shipbuilding engineering Harbin Engineering University Harbin 150001 China

This paper is concerned with the free vibration analysis of open circular cylindrical shells with either the two straight edges or the two curved edges simply supported and the remaining two edges supported by arbitrary classical boundary conditions. Based on the Donnell-Mushtari-Vlasov thin shell theory, an analytical solution of the traveling wave form along the simply supported edges and the modal wave form along the remaining two edges is obtained. With such a unidirectional traveling wave form solution, the method of the reverberation-ray matrix is introduced to derive the equation of natural frequencies of the shell with different classical boundary conditions. The exact solutions for natural frequencies of the open circular cylindrical shell are obtained with the employment of a golden section search algorithm. The calculation results are compared with those obtained by the finite element method and the methods in the available literature. The influence of length, thickness, radius, included angle, and the boundary conditions of the open circular cylindrical shell on the natural frequencies is investigated. The exact calculation results can be used as benchmark values for researchers to check their numerical methods and for engineers to design structures with thin shell components.

关键词： Open circular cylindrical shell Method of reverberation-ray matrix Free vibration analysis Donnell-Mushtari- Vlasov thin shell theory Analytical wave form solution

Three-dimensional properties of mesoscale cyclonic warm-core and anticyclonic cold-core eddies in the South China Sea

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Acta oceanologica Sinica 2021年第10期40卷 17-29页

作者： Wenjin Sun Yu Liu Gengxin Chen Wei Tan Xiayan Lin Yuping Guan Changming Dong School of Marine Sciences Nanjing University of Information Science and TechnologyNanjing 210044China Southern Marine Science and engineering Guangdong laboratory(Zhuhai) Zhuhai 519080China Marine Science and Technology College Zhejiang Ocean UniversityZhoushan 316022China state key laboratory of Tropical oceanography South China Sea Institute of OceanologyChinese Academy of SciencesGuangzhou 510301China College of ocean Science and engineering Shandong University of Science and TechnologyQingdao 266590China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China

In general,a mesoscale cyclonic(anticyclonic)eddy has a colder(warmer)core,and it is considered as a cold(warm)***,recently research found that there are a number of"abnormal"mesoscale cyclonic(anticyclonic)eddies associated with warm(cold)cores in the South China Sea(SCS).These"abnormal"eddies pose a challenge to previous works on eddy detection,characteristic analysis,eddy-induced heat and salt transports,and even on mesoscale eddy *** on a 9-year(2000–2008)numerical modelling data,the cyclonic warm-core eddies(CWEs)and anticyclonic cold-core eddies(ACEs)in the SCS are *** study found that the highest incidence area of the"abnormal"eddies is the northwest of Luzon *** terms of the eddy snapshot counting method,8620 CWEs and 9879 ACEs are detected,accounting for 14.6%and 15.8%of the total eddy number,*** size of the"abnormal"eddies is usually smaller than that of the"normal"eddies,with the radius only around 50 *** the generation time aspect,they usually appear within the 0.1–0.3 interval in the normalized eddy *** survival time of CWEs(ACEs)occupies 16.3%(17.1%)of the total eddy *** on two case studies,the intrusion of Kuroshio warm water is considered as a key mechanism for the generation of these"abnormal"eddies near the northeastern SCS.

关键词： mesoscale eddy cyclonic warm-core eddy anticyclonic cold-core eddy Kuroshio intrusion South China Sea abnormal mesoscale eddy

Multi‑Crack Interaction and Influence on the Spherical Pressure Hull for a Deep‑Sea Manned Submersible

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Journal of Marine Science and Application 2021年第3期20卷 491-503页

作者： Rujun Li Yongmei Zhu Wenjing Fang Baoji Yin School of Mechanical engineering Jiangsu University of Science and TechnologyZhenjiangZhenjiang 212003China

This study investigates the interaction and influence of surface cracks on the spherical pressure hull of a deep-sea manned *** finite element model of the spherical hull is established,and a semi-elliptical surface crack is inserted in the welding toe of the spherical hull as the main *** the combined effect of external uniform pressure and welding residual stress at the weld toe,the stress intensity factor(SIF)is obtained based on the M-integral *** disturbing cracks at different positions on the spherical hull surface,the interaction and influence between multi-cracks are revealed by numerical *** results show that the existence of the disturbing crack has a great influence on the stress intensity factor of the main crack,and the influence is different with the different location of disturbing *** study of the interaction of multiple cracks under different interference factors and the influence of disturbing cracks on the main crack can provide some reference for future engineering applications.

关键词： Spherical pressure hull Surface cracks Multi-crack interaction Stress intensity factor Welding residual stress Manned submersible Finite element model

Flow Behavior behind a Freely Suspended Cylinder in the Wake of a Stationary Cylinder

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Flow Behavior behind a Freely Suspended Cylinder in the Wake...