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Experimental Investigation of the Resistance Performance and heave and Pitch Motions of Ice-Going Container Ship Under Pack Ice Conditions

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China Ocean Engineering 2018年第2期32卷 169-178页

作者： GUO Chun-yu XIE Chang ZHANG Jin-zhao WANG Shuai ZHAO Da-gang College of Shipbuilding Engineering Harbin Engineering UniversityHarbin 150001China Nantong COSCO KHI Ship Engineering Co.Ltd Nantong 226005China Shanghai Marine Equipment Research Institute Shanghai 200031China

In order to analyze the ice-going ship’s performance under the pack ice conditions, synthetic ice was introduced into a towing tank. A barrier using floating cylinder in the towing tank was designed to carry out the resistance experiment. The test results indicated that the encountering frequency between the ship model and the pack ice shifts towards a high-velocity point as the concentration of the pack ice increases, and this encountering frequency creates an unstable region of the resistance, and the unstable region shifts to the higher speed with the increasing concentration. The results also showed that for the same speed points, the ratio of the pack ice resistance to the open water resistance increases with the increasing concentration, and for the same concentrations, this ratio decreases as the speed increases. Motion characteristics showed that the mean value of the heave motion increases as the speed increases, and the pitch motion tends to increase with the increasing speed. In addition, the total resistance of the fullscale was predicted.

关键词： synthetic ice pack ice concentration heave pitch peak collision value

Seepage failure by heave in sheeted excavation pits constructed in stratified cohesionless soils

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Frontiers of Structural and Civil Engineering 2019年第6期13卷 1415-1431页

作者： Serdar KOLTUK Jie SONG Recep IYISAN Rafig AZZAM HPC AG Stuttgart 70597Germany Department of Engineering Geology and Hydrogeology RWTH Aachen UniversityAachen D-52064Germany Civil Engineering Faculty Istanbul Technical UniversityIstanbul 34646Turkey

In this study,experimental and numerical investigations are performed to clarify the seepage failure by heave in sheeted excavation pits in stratified cohesionless soils in which a relatively permeable soil layer(Kupper)lies above a less permeable soil layer(Klower)between excavation base and wall *** is shown that the evaluation of base stabilities of excavation pits against seepage failure by using Terzaghi and Peck's approach leads to considerably lower critical potential differences than those obtained from the model *** the other hand,a relatively good agreement is achieved between the results of the model tests and the finite element(FE)*** investigations are performed by using axisymmetric excavation models with various dimensions and ground conditions,and a comparison between the results obtained from Terzaghi and Peck's approach and finite element analyses is given.

关键词： seepage failure by heave cohesionless stratified soil model test Terzaghi and Peck's approach FE analysis

Effects of volumetric allocation on heave response of semisubmersible in deep sea

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Science China(Technological Sciences) 2009年第3期52卷 651-657页

作者： ZHANG HuiQin LI JiaChun Institute of Mechanics Chinese Academy of SciencesBeijing 100190China

The configuration of semisubmersibles consisting of pontoons and columns and their corresponding heave motion response in incident progressive waves are examined. The purpose of the present study is to provide a theoretical approach to estimating the effects of volumetric allocation on natural period and response amplitude operator (RAO) in heave motion. We conclude that the amplitude of heave motion response can be considerably suppressed by appropriately adjusting volumetric allocation so that the natural heave period keeps away from the range of wave energy. The theoretical formulae are found in good agreement with the corresponding computational results by WAMIT.

关键词： semisubmersible heave natural period RAO WAMIT

A NEW MODEL OF FROST heave PREDICTION FOR CLAYEY SOILS

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Science China Chemistry 1991年第10期34卷 1225-1236页

作者：陈肖柏王雅卿 Lanzhou Institute of Glaciology & Geocryology Academia Sinica Lanzhou 730000 PRC

After analysing the results of systematic experimental research on frost susceptibility tests, a new frost heave prediction model, including the heave ratio η and rate R, is first proposed in this paper. Six main factors influencing frost heave are considered: initial water content W, initial dry unit weight γd, frost penetration rate Vf, groundwater level Hw, plasticity index Ip and ion content S. The model could be expressed by: η= B0WB1γBd2VB31·exp(B4Hw)exp(B5Ip)exp(B6S) and R = B’0WB’1γB’2dexp(B’3Hw)exp(B’4Ip)exp(B’5S) with a good reliability, where B0 to B6 and B’0 to B’5 are the characteristic constants of clayey soils. The effect of each factor on frost susceptibility of soils is discussed also.

关键词： frost susceptibility frost heave ratio frost heave rate frost heave prediction.

Control mechanism and technique of floor heave with reinforcing solid coal side and floor corner in gob-side coal entry retaining

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International Journal of Mining Science and Technology 2012年第6期22卷 832-836页

作者： Chen Yong Bai Jianbiao Yan Shuai Xu Ying Wang Xiangyu Ma Shuqi State Key Laboratory of Coal Resources and Mine Safety School of MinesChina University of Mining & Technology Faculty of Engineering University of Wollongong

Floor heave is the most common convergence in gob-side entry *** paper analyzes the form,process and characteristics of gob-side entry retaining with the comprehensive methods of theoretical analysis,numerical simulation and the field *** results present that bending and folding floor heave is the main factor in the stage of the first panel mining;squeezing and fluidity floor heave plays a great role in the stable stage of gob-side entry retaining;the combination of the former two factors affects mainly the stage of the second mining ahead;abutment pressure is a fundamental contribution to the serious floor heave of gob-side entry retaining,and sides corners of solid coal body are key part in the case of floor heave controlling of gob-side entry *** heave of gob-side entry retaining can be significantly controlled by reinforcing sides and corners of solid coal body,and influence rules on the floor heave of gob side entry retaining of sides supporting strength and the bottom bolt orientation in solid coal side are *** results have been successfully applied in gob-side entry retaining of G20-F23070 face haulage roadway in #2 coal mine of Pingmei Group,and the field observation shows that the proposed technique is an effective way in controlling the floor heave of gob-side entry retaining.

关键词： Gob-side entry retaining Abutment pressure Forms of floor heave Reinforcing sides of solid coal side Bolt in a floor corner

Investigation of heave Response of the Deepwater Octagonal FDPSO Using Various heave Plate Configurations

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Journal of Marine Science and Application 2017年第4期16卷 446-457页

作者： Chenfang Yu Zhiqiang Hu Shisheng Wang State Key Laboratory of Ocean Engineering Shanghai Jiao Tong University Shanghai 200240 China Jiangnan Institute of Technology Jiangnan Shipyard (Group) Co. Ltd Shanghai 201913 China School of Engineering Newcastle University Newcastle upon Tyne NE1 7RU UK China National Offshore Oil Corporation Research Institute Beijing 100027 China

heave plates can be employed to control undesirable heave motion amplitudes of the deepwater octagonal Floating, Drilling, Production, Storage, and Offloading(FDPSO) platform. Numerical simulations and model tests were applied to analyze and investigate the hydrodynamic response and the feasibility of the heave plate configurations. The diameter and the depth below the free surface of a single-layer heave plate, as well as the spacing of two-layer heave plates, were considered as the primary variables when studying the effect of heave plates on FDPSO hydrodynamics. The analysis results indicate that the heave plate diameter significantly affects the heave hydrodynamics, and heave performance could be improved with an increased diameter. In addition, increasing the depth below the free surface of a single-layer heave plate does not effectively suppress the heave motion within the range of draft depths tested. The target FDPSO obtained better heave characteristics with increased spacing between the two-layer heave plates. Furthermore, the global performances of the octagonal FDPSO with these typical heave plate configurations were comparatively analyzed. The results indicate that from a hydrodynamic point of view, the single-layer heave plate configuration has an advantage over the two-layer heave plate configuration.

关键词： octagonal FDPSO hydrodynamics heave plate heave motion numerical analysis model test

Frost-heave properties of saturated compacted silty clay under one-side freezing condition

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Research in Cold and Arid Regions 2017年第3期9卷 273-279页

作者： Hong Yan Ma Feng Zhang De Cheng Feng Kang Wei Tang College of Civil Engineering Fuzhou University School of Transportation Science and Engineering Harbin Institute of Technology

In seasonally frozen regions,the frost-heave properties of soil play a significant role in its upper-structure performance and *** investigate the frost-heave behaviors of saturated,compacted silty clay soil widely used as subgrade material,a series of one-side freezing tests was carried out;and the freezing depth and frozen front effected by the compactness,temperature,overburden pressure,and water-supply condition were analyzed and *** results show that the moving speed of the frozen front and growth rate of the frozen depth are positively *** frost heave is maximum in the frost-heave stability *** frost ratio of saturated soil is proportional to the water supply and cooling temperature under a one-side freezing *** frost ratio of saturated soil is inversely proportional to the initial compactness of the soil specimen and the overburden pressure.

关键词： seasonally frozen regions saturated silty clay soil frost heave freezing front factor-sensitivity analysis

A mathematical approach to evaluate maximum frost heave of unsaturated silty clay

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Research in Cold and Arid Regions 2017年第5期9卷 438-446页

作者： Lin Geng XianZhang Ling Liang Tang Jun Luo XiuLi Du Beijing Key Lab of Earthquake Engineering and Structural Retrofit Beijing University of Technology School of Civil Engineering Harbin Institute of Technology State Key Laboratory of Frozen Soil Engineering Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences

Maximum frost heave of unsaturated frost-susceptible soils,in conjunction with a high water table,is an important consideration for the design of foundations in seasonally frozen ***,it is necessary to evaluate accurately and efficiently the maximum frost heave for a given *** this purpose,a series of one-sided freezing experiments was conducted on unsaturated silty clay in an open *** cooling of sufficient duration was applied to the soil sample's top,while constant above-zero temperatures were maintained at the ***,a simple methodology for calculating maximum frost heave at a given cooling temperature was derived utilizing information obtained within the limited time allotted for each *** this basis,an empirical equation for defining maximum frost heave as a function of cooling temperature and overburden pressure was ***,this study provides a simple and practical procedure that is applicable to the evaluation of maximum frost heave of unsaturated frost-susceptible soils.

关键词： mathematical approach maximum frost heave multistage freezing experiment unsaturated silty clay

Frost heave analysis of ballasted track above box culvert and its influence on train vibration

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Research in Cold and Arid Regions 2017年第3期9卷 229-235页

作者： Bin Luo Hao Lai Tatsuya Ishikawa Tetsuya Tokoro Graduate School of Engineering Hokkaido University Faculty of Engineering Hokkaido University National Institute of Technology Tomakomai College

The uneven frost heave of frost-susceptible subgrade soil causes track irregularity,which highly enhances train vibration and affects the comfort and safety of railway *** paper presents a coupled thermo-hydro-mechanical(THM)analysis for the freezing behavior of railway located above a box *** vertical acceleration of the vehicle,an indicator of riding comfort,is predicted through a vehicle dynamic *** results reveal that the existence of a box culvert changes the subgrade thermal pattern,leading to a deeper frost penetration *** frost heave amount above the box culvert is larger than the adjacent section,resulting in uneven track structure upheave and track *** frostinduced track irregularity highly affects train vibration.

关键词： railway box culvert coupled analysis uneven frost heave track irregularity train vibration