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Wind forces on modern ship forms effect on performance
AuthorsW B Van Berlekom
Date published1980
AbstractA systematic series of wind tunnel tests examine direct wind forces and moments on ships of different above-water structures particularly size and position of deckhouse (tanker containership RORO small craft) and induced forces and moments on underwater hull. Results include - wind coefficient curves added resistance due to drift and rudder angles effect of added resistance on propeller efficiency wind effects on manoeuvring.
AuthorsW B Van Berlekom
Date published1980
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Experimental study on vertical ice loads acting on multi- leg structures
AuthorsT Terashima
Date published2000
AbstractIf an ice sheet adfreezes to a structure with a circular cross-section such as the pile of a pier or a mooring pile set in the water of a cold region vertical ice loads act on the structure and can cause the uprooting of a pile if there is fluctuation in the water level due to the tide or other factors. Therefore vertical ice loads must be considered when designing structures that will be subjected to ice loads. The vertical ice load acting on a single pile structure can be estimated using the theoretical calculation method proposed by the authors. In this study field experiments are carried out for the first time on ice loads acting on multi-leg structures to try to establish a theoretical method for calculating ice loads acting on such structures.
AuthorsT Terashima
Date published2000
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On the effect of water on deck on ship motion
AuthorsDimitris Spanos ; Apostolos Papanikolaou ; George Tzabiras
Date published2002
AbstractThe effect of trapped water on deck or the interior compartments of ships on ship motions is closely investigated by use of a non-linear numerical simulation method. The employed method enables the efficient simulation of the wave excited coupled ship - trapped water motions and proves to be a very valuable tool for the assessment of the survivability of flooded ships in waves. A detailed study has been carried out to more carefully investigate the coupling effects between the ship and the floodwater mass that can be expressed through a resultant interaction force. This interaction force has been approximated both by a simplified model employed by the present simulation method and also by a more accurate CFD code and satisfactory agreement between the results of both approaches has been obtained.
AuthorsDimitris Spanos ; Apostolos Papanikolaou ; George Tzabiras
Date published2002
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On the reliability and risk analysis of subsea blowouts preventers with focused attention on DP rigs
AuthorsNilo de Moura Jorge
Date published2005
AbstractThis paper provides a selection of findings on the reliability and risk analysis of submarine blowout preventers (BOPs) achieved in recent studies in which the author has participated among technicians in Petrobras and Rio de Janeiro Federal University - UFRJ. Special attention is given to the deepwater and ultra deepwater scenarios. The riser safety margin tends to be unavailable as the water depth becomes deeper and so in an emergency disconnection the safety isolation of the well tends to be relied on the BOP mechanical barriers only. In this context risks on different configurations of the BOP are compared and their results discussed with focused attention on main factors of risk. Finally there has been visible progress on BOP reliability within recent years and a number of good operational practices in place are also mentioned in the paper.
AuthorsNilo de Moura Jorge
Date published2005
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Uncertainties in the estimation of fluid loading on offshore structures with special emphasis on wind forces
AuthorsS Singh
Date published1989
AbstractSome of the major uncertainties in the estimation of mean drag forces on offshore structures especially those generated by wind are presented and discussed. Standard techniques as suggested by published criteria and guidelines are used to illustrate some of these uncertainties for three cases. These are loads on the legs of a jack-up unit loads on a group of conductors and finally wind forces on a semi-submersible unit. Potential problems in the use of wind tunnel modelling are also discussed and recommendations made for a unified and consistent approach to estimating mean drag forces on offshore structures.
AuthorsS Singh
Date published1989
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Report on the investigation of a fatal accident on baord Arco Adur on the River Medway 25 February 2003
AuthorsMarine Accident Investigation Branch
Shelf Location40e
AuthorsCatalogue numberMarine Accident Investigation Branch
UNK
Shelf Location40e
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BSRA Technical Memorandum No. 125 Reports on foreign observers' course on the nuclear ship 'Savannah'. Report on Visits
AuthorsJ A Dodd ; S Macdonald
Shelf Locationin storage
AuthorsPublisherJ A Dodd ; S Macdonald
British Ship Research Association
Shelf LocationDate publishedin storage
1960
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Report on the investigation of the grounding of the class VI passenger vessel Pride of the Dart on Mew Stone rocks near the entrance to the River Dart on 28 June 2002
AuthorsMarine Accident Investigation Branch
Shelf Location40d
AuthorsCatalogue numberMarine Accident Investigation Branch
UNK
Shelf Location40d
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A general scheme for substructuring on-line hybrid test on planar moment frames (the neural network model)
AuthorsC Zavala ; K Ohi ; K Takanashi et al.
Date published1995
AbstractA general scheme for on-line hybrid substructuring simulation is presented aiming to achieve the deformed position of testing specimen. An artificial neural network is used as predictor of the incremental forces on the specimen to achieve the displacements of the system. Firstly a look is taken at the substructuring on-line hybrid test. Next the artificial neural network predictor is described. Lastly the prototype test is discussed.
AuthorsC Zavala ; K Ohi ; K Takanashi et al.
Date published1995
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On the sidewall effects on the non-linear wave loads on a TLP-like structure in a wave tank: analysis of the non-linear near-trapping
AuthorsFabrizio d'Este ; Riccardo Codiglia ; Giorgio Contento
Date published2002
AbstractThe non-linear interaction in diffraction regime of regular waves with a TLP-like structure is studied using the Numerical Wave Tank method. In particular the higher order 'near trapping' phenomenon is analysed with emphasis on the sidewall reflection effects on the harmonic components of the wave elevation and of the forces on the cylinders. From prelimineary results using the Fourier analysis with the sliding window technique it seems that first order in-line terms is only weakly affected by the dimensions of the basin whereas the first order side force on the lateral cylinder shows evident interference effects. At the same time the amplitude of the second order terms of the forces shows a smoother variation with time for the larger basin.
AuthorsFabrizio d'Este ; Riccardo Codiglia ; Giorgio Contento
Date published2002
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Effects of avoidance of heavy weather on the wave induced load on ships
AuthorsZhi Shu ; Torgeir Moan
Date published2005
AbstractWave-induced hull girder loads such as vertical bending moment amidships are very important for design. The effect of heavy weather avoidance on the long-term wave-induced loads on ships is evaluated. Two hydrodynamic codes VERES based on a 2D strip theory and WASIM based on a 3D Rankine panel method are used to calculate the wave-induced loads and motions on various vessels. Two models for heavy weather avoidance are proposed. The first is based on the assumption that operational criteria relevant to vertical acceleration green water and bottom slamming are fulfilled. The second is based on the assumption that the sea state forecasts are available to the shipmaster and that rerouting is made. Based on the first model considering avoidance of heavy weather and the hydrodynamics results calculated from two codes wave-induced hull girder loads are obtained. The results are discussed - in particular the effect of different hydrodynamic codes and various scatter diagrams. The long-term prediction of wave-induced hull girder loads considering the effect of avoidance of heavy weather will give a relatively more realistic evaluation of the extreme hull girder loads. Finally the results from ship rules are also re-evaluated compared with the long-term prediction with and without heavy weather avoidance.
AuthorsZhi Shu ; Torgeir Moan
Date published2005
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A finite-element model for in-situ behaviour of offshore pipelines on uneven seabed and its application to on-bottom stability
AuthorsB A Ose ; R Nystrom ; A Damsleth et al.
Date published1999
AbstractA Finite Element (FE) model for simulation of the in-situ behaviour of offshore pipelines laid on a 3-D seabed with focus on on-bottom stability is presented. 3-D FE simulations are provided as design examples. After some introductory information a look is taken at the area of application and model details. Next validation of the FE model is addressed followed by acceptance criteria and design examples.
AuthorsB A Ose ; R Nystrom ; A Damsleth et al.
Date published1999
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Discussion on high-speed boat run-up on rocks and its impact force
AuthorsGuoyu Chen
Date published2006
Abstract'Boat run up on rocks' means boat and rock collision. This also refers to boat collision with things fixed under the water such as piers. There is much interest and there has been much research in this area. A formula on the calculation of the impact of force of 'boat run up on the rocks' is presented. The formula includes parameters such as angle speed rigidity and qualities of the 'impact pair' and may provide help with the designing of bows for high-speed boats.
AuthorsGuoyu Chen
Date published2006
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Marine Accident Investigation Branch Report No 37/2000 Report on the Investigation of a Rupture of the Port Economiser on board Island Princess resulting in two deaths on 7 December 1997
AuthorsMAIB
PublisherDETR
AuthorsDate publishedMAIB
2000
PublisherDETR
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Observations on the Effects of Lightning on Floating Bodies with an account of a new method of applying fixed and continuos conductors of electricity to the masts of ships in a letter addressed to Vice-Admiral Sir Thomas Byam Martin. Harris on Lightning
AuthorsWilliam Snow Harris
Shelf LocationRR11
AuthorsWilliam Snow Harris
Shelf LocationRR11
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Environmental Forces on Offshore Structures and Their Prediction Volume 26 of Advances in Underwater Technology, Ocean Science and Offshore Engineering
AuthorsSociety for Underwater Technology (SUT)
Shelf Location213a
AbstractConf held by SUT in London 28-29 November 1990 Papers are The use of joint probability in deriving environmental design criteria The effect of frequency spreading on a two component sea state Wave kinematics within the crest to trough region Review of recent analytical and approximate solutions of wave-current interaction Wave current interaction In-line forces on fixed cylinders in regular and random waves Marine roughness and fluid loading On the effects of wake re-encounter for wave forces on cylinders Wave and current forces on conductor pipe groups Coupled experimental and analytical investigation of hydrodynamic forces on a jacket in waves Slender well conductor design Applicability of 3-D wave loads in offshore design A critical assessment of Turkstra's Rule related to the reliability of offshore structures A new stress range distribution model for fatigue analysis under wave loading Environmental loading on fixed offshore platforms Prediction of loads on floating production systems Wind loading and dynamic response of a floating production platform in waves Wave-drift damping of a TLP Effects of joint probability and short crestedness in designing a compliant structure
AuthorsPublisherSociety for Underwater Technology (SUT)
Kluwer Academic
Shelf LocationDate published213a
1990
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Study on synthesis optimisation of speed and sea keeping performance based on on-line simulation of high-speed single-hull ship
AuthorsYi Wang ; Sing-lin Yang
Date published2006
AbstractThe main elements of the navigation performance of a ship are its speed its manoeuvrability and its seakeeping. The mathematical model of a high-speed single hull ship's propulsion system (adjustable-pitch screw propulsion) is firstly established. Then based on MATLAB the simulation model of the propulsion system is built with the help of simulation software 'Simulink'. The intelligent control on the propulsion system is carried out using fuzzy controller of Look-Up Table. After that the mathematical model of synthesis optimisation of high-speed single-hull ship is established by considering control speed and seakeeping performances. Based on the aforementioned established simulation model and applying GAOT MATLAB's optimisation toolbox for GA (Genetic algorithm) the optimisation design of the system is carried out. An example is given and the accuracy and reliability of the simulation and optimisation models are validated.
AuthorsYi Wang ; Sing-lin Yang
Date published2006
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Guidelines on the impact of aggregate extraction on European marine sites
AuthorsPosford Duvivier Environment
Date published2003
AbstractThe EC Habitats Directive aims to promote the conservation of habitats and species within the European Union by designating sites known as SACs (special areas of conservation). The UK Marine SACs Project aims to promote the implementation of the Habitats Directive in marine areas through trialling the establishment of management schemes on 12 sites in the UK and by providing proven good practice and guidance to practitioners in the UK and Europe. To support the establishment of these management schemes the Project is undertaking a series of tasks to collate and develop the understanding and knowledge needed. One of the areas for providing guidance to those developing the schemes concerns the interaction between human activities and marine features. Human activities have an important role in the management of marine features and may have both beneficial and damaging impacts. This report has been prepared to provide information and guidance on aggregate extraction activities. There are a number of objectives for the series of guidance documents forming part of the UK Marine SACs Project. The overall aim of this task is to provide information on the potential impacts of aggregate extraction on marine and coastal habitats and species listed in Annexes 1 and 2 of the Habitats Directive and to provide guidance on the assessment of potential impacts. Among the habitats and species specified in Annexes 1 and 2 several are marine features and SACs have already been selected for many of these in the UK. One initiative now underway to help implement the Habitats Directive is the88712 Guidelines on the use of high-modulus synthetic fibre ropes as mooring lines on large tankers OCIMF
AuthorsPosford Duvivier Environment
Date published2003
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Tenth International Towing Tank Conference Volume 2
AuthorsNat Phys Lab
Shelf Location213c
AbstractTenth Int Conf held in Teddington in Sept 1963 Papers are The resistance tests on the ITTC Standard Model Results of resistance tests of standard model Resistance tests of standard model Resistance tests of standard laminated fibre glass model An analysis of some Mitsubishi standard model tests Further model tests with a 760 tdw motor coaster A study of the turbulence stimulation device in the model experiment on ship form Actual ship thrust measurement as a means of breaking down the correlation allowance into its components (abstract) Some experiments of yawing effect on ahead resistance of ships (abstract) Further experiments of yawing effect on ahead resistance of ships (abstract) Frictional resistance in towing tanks Variation of viscous drag with froude number The influence of form and scale on model and ship resistance Formal contribution On the flat plate experiments of Kyushu University (abstract) Some remarks on the logical approach of model ship correlation Considerations on the experimental determination of the form effect from results about transition line Form effects on viscous resistance and their estimation for full ships Testing of standard model - Kryloff Shipbuilding Research Institute The effect of loading on wake and thrust deduction Some remarks on the logical approach to ship model correlation The influence of scale or size on ship model tests involving propeller generated vibration Propulsion trial code Recent studies by the British Towing Tank Panel of ship model correlation Calculation of the hydrodynamic exciting damping coupling and inertial forces of ship propellers based on wake distribution and90767 Terminal compatibility MER
AuthorsPublisherNat Phys Lab
Min of Tech
Shelf LocationDate published213c
1963
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Environmental forces on engineering structures
Authorsedited by C A Brebbia, P L Gould, J Munro
Shelf Location224e
AbstractConf held in July 1979 in London Papers are Environmental loadings on concrete cooling towers - types likelihood effects and consequences Numerical simulation of three-dimensional separated flow; a first step Wind loading on structures Safety considerations for natural draught cooling towers under wind load Dynamic effects of wind on offshore towers Effects of soil-structure interaction on the dynamic along-wind response of structures The wind induced dynamic response of the Wye bridge Investigation on the vibrational behaviour of a cable-stayed bridge under wind loads A study of the measured and predicted behaviour of a 46-storey building Experimental study of wind forces and wind-induced vibrations at a steel lighthouse tower Simplified models of large-wind-turbine open-truss tower Wind loading and missile generation in tornado Earthquake floor response and fatigue of equipment in multi-storey structures An integrated procedure to compute wave loads on hybrid gravity platforms Wave forces on elliptical cylinders by finite element method Dynamic analysis of marine risers involving fatigue and corrosion Spectral dynamic fatigue analysis of the ANDOC DUNLIN `A' platform A computational approach for the analysis of fixed offshore structures including piling Slam load histories on cylinders Theoretical analysis on the transverse motion of a buoy by surface wave Probabilistic design of a fibre-reinforced concrete floating pontoon A structural problem of piers resting on piles
AuthorsPublisheredited by C A Brebbia, P L Gould, J Munro
Pentech Press
Shelf LocationDate published224e
1979