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In this research a numerical experiment was conducted on a retaining structure experiencing earthquake loading. For a backfill consisting purely of sandy soils the seismic lateral thrust acting on the structure was first determined by simulating both sinusoidal load as well as the earthquake time history of an actual earthquake. A part of the backfill immediately behind the structure was then substituted by lightweight Expanded Polystyrene (EPS) geofoam which acts as the compressible buffer. The effect of such lightweight compressible buffer material on the developed seismic thrust was then examined. The results show that the use of the EPS geofoam as a compressible buffer yields significant reduction of the lateral seismic thrust against a structure.

According to comprehensive theories of navigation animals navigate using two complementary strategies: dead reckoning and long-term associations. The former informs the subject in a continuous manner on its actual location with respect to an earth-bound or absolute co-ordinate system. The latter are long-term associations between particular landmarks and specific locations which allow the animal to find its way within a familiar environment. Research is presented focusing on homing strategies shown by golden hamsters in the hoarding situation. The main areas of consideration are: how are signals computed to yield the homing vector; on what conditions to hamsters rely on optical references rather than on internal dead reckoning and what is the nature of good landmarks; and finally can we maintain the cognitive map hypothesis on the level of our subjects and assume that dead reckoning is an ubiquitous process the outcome of which is automatically fed into the map system.

An inclining test is extremely difficult to run on board a live offshore unit. Experience is presented on the successful conduct of a test where tanks were adapted to shift a controlled heavy load of ballast water across a large ship. This unique test was held in open and deep waters with the ship under dynamic position control. A dedicated loading computer is an essential tool on board offshore craft. In the hands of a competent crewmember it is capable of producing the daily static calculations. But its stability verification relies solely on pre-stored KG' limit data. For the complex internal arrangements on board offshore construction vessels a more suitable alternative to satisfy the requirement for an operationally safe vessel needs to be sought. It is proposed to develop a probabilistic stability assessment method for the offshore industry. A Formal Safety Assessment approach based on risk analysis techniques may yield more realistic stability envelopes for offshore construction vessels.

The Sable Offshore Energy Project (SOEP) 26” offshore gathering line and the associated interfield lines are the first major offshore pipelines on the East Coast of Canada. The benefits of early cooperation betweeen Owner Designer and Installer are discussed with opportunities for some interesting synergies arising from parallel engineering and planning of installation. The sea states and seafloor conditions around Sable Island impose some substantial loading considerations which resulted in some novel design and installation solutions. These are described together with some of the novel cathodic protection considerations used on the project. Some interesting certification and regulatory challenges encountered in progressing with the pipeline are also described. The state of the art welding and automatic ultrasonic testing approach and its beneficial impact on production lay rates are reviewed.

Development and improvement of gas turbines can be significantly supported by CFD (computational fluid dynamics) provided that the computational models are reliable and efforts regarding time and memory reasonable. The applicability of the models to reproduce combustion of low calorific fuels is investigated. The EBU (Eddy Break Up) model has been widely used until now. However heightened interest in environmental matters and stricter regulations caused questions to be raised about the use of EBU. PDF (probability density function) methods are claimed to be superior. The complex problem is considered of simulation of a reacting fluid in a highly swirling flow field. However the concentration is on an investigation of the combustion model bearing in mind that the quality of numerical results does strongly depend on both the turbulence model as well as the combustion model. The results presented show the influence of combustion model and turbulence model on the flow field fuel concentration as well as pattern factor. The models are evaluated by comparison with experiments.

It is desirable to be able to use the powerful methods of frequency domain analysis on models of the slowdrift motion of moored vessels. As such models usually are nonlinear a method of linearization is needed. Among such methods the method of statistical linearization should be used. This method based on a minimum variance principle is described. It is shown that the result depends on the correlation between the response variables and that the joint distribution of the variables is needed. By a simple example it is demonstrated that linearizing the response variables independently may lead to significant error. The method involves evaluation of multidimensional statistical expectation for which Hermite integration is used. It may be sufficient to use as few as four points in each dimension. Finally a numerical example of the method is given.

A model which predicts the dynamic tensions and curvatures in a subsea umbilical during installation is presented. The dynamic tension results for a range of wave periods and layback position are given to illustrate the model. The results show the highly non-linear nature of the problem. Firstly equations of motion are looked at. Next the numerical model is described. Lastly the application to an umbilical installation analysis is discussed. It is concluded that the presented model is suitable for establishing operational limits for subsea umbilical installation and has the potential for real time application.

RBI (risk-based inspection) and on-site maintenance are the key points to ensure the success of a structural integrity management program for FPSOs. Generally as the structure gets older and some operational changes or extended life are requested by the operators the in-service planning of the inspection and repair activities increases in complexity. This paper provides guidance on in-service planning and management drawing directly from the operating and risk-based inspection experience of a fleet consisting of five Petrobras' units located at Campos Basin. Specifically the paper outlines the inspection planning that addresses these unique features and applications and discusses experiences related to the implementation of the inspection plans. It also provides general guidance on the organisation presentation and steps to ensure the asset is fit-for-purpose while being functional and easy to manage and implement for operations.

The basic requirement of any breakwater is to dissipate the energy in the incident waves in order to maintain preferably calm water inside the harbourage area to facilitate smooth conduct of loading and unloading of passengers and cargo. The concept of SBW (semi-circular breakwater) is one of the recently emerging new types of breakwater. The caisson of the SBW is semi-circular in shape and hollow and is founded on a rubble mound. Therefore the weight and amount of materials required are reduced. The world's first-ever semi-circular breakwater of rear dissipating type has been built at the port of Miyazaki Japan. A SBW model with its seaside perforated has been subjected to the action of regular waves. The wave-induced dynamic pressures and run-up on the caisson of SBW was measured. Tests have been carried out for two percentages of perforations and in three different water depths. The effect of water depth and the percentage of perforations on the dynamic pressures and run-up are presented and discussed. The details of experimental set-up procedure data analysis and results are reported.

Total is pursuing its deepwater field development activity offshore Angola in Block 17 in a water depth of about 1400 m. In order to develop accurate metocean design data and also to assist offshore operations Total started an extensive acquisition campaign in March 2001 with an instrumentation comprising a wave buoy later enriched by current profilers an anemometer and a met station. An insight into the comprehensive analyses that have been carried out on the wave-wind-current simultaneous records is presented with a particular focus on complex directional wave spectra joint probabilities of the various metocean parameters and their impact on the design.

On 12 October 2000 terrorists bombed the USS Cole. The chronology of events are discussed along with the associated engineering decisions that culminated in the successful recovery float-on loading (dry-docking) off the coast of Yemen and the safe transit home of this fully armed and badly-damaged warship. Several issues specific to the on load are clarified and more details are provided on the off load. After some introductory information a brief history is given of heavy lift transport. Next the attack is outlined. This is followed by a look at the rescue and recovery. Lastly the float-off is dealt with.

SCRs (steel catenary risers) have proved to be feasible for use on floating production facilities. The activities and critical issues related to the preparation qualification reeling and installation of two 10 inch SCRs by Petrobras in the Roncador field offshore Brazil are described. A combined installation technique with J-lay of the critical touchdown area and traditional reeling for the remaining flowline-riser part is applied. The operations related to reeling the pipe sections onto the reel reeling off welding on site (J-lay sections) and transfer to P-36 are outlined. The analyses performed to evaluate the effects of using the reeling method for installation of the risers are detailed. The following issues are addressed: riser torsional effects due to residual curvature; effects of residual stresses; ovalisation; strain concentrations; variability in yield strength; riser analyses; reeling analyses; fatigue aspects; hoop buckling; and propagating buckling. Graphs and diagrams appear on pages 6 to 8.

Upon the request of PEMEX a vibration assessment was conducted on an offshore platform located in the Bay of Campeche. The study consisted in two parts - the first being considered in another paper and the second one involving the response analysis under uncertain conditions of wave height. The uncertainty on the wave loading was considered through the annual probabilities that given wave heights are exceeded. The probability that the platform response exceeds an allowable threshold conditional to given wave heights was assessed. Those conditional probabilities were weighted later on over the annual probabilities that those wave heights are exceeded. The responses are displacements accelerations and forces. The lateral strength of the platform was calculated by assuming a failure mechanism composed by the simultaneous formation of plastic hinges at the ends of the platform legs.

Improved permanent-magnet motor technology has made it possible to install a propulsion motor in an underwater case for direct drive of the propeller. This has given rise to the rapid development of POD propulsion - the latest development trend of the electric ship. Research is described on a theoretical method for predicting the steady hydrodynamic performances of a POD propulsor using the vortex lattice method and the surface element method of the lifting surface theory. Based on an existing numerical computation method for the propeller a theoretical potential flow computation method is established for predicting the steady hydrodynamic performance of a POD propulsor. A real case computation is carried out. The results obtained agree well with those obtained from experiments. After this previous research on the propulsion performance of a single-screw propeller is used to further optimise the trailing vortex model of the propeller. A comparison of the real case calculation test results and the original calculation is made. The comparison shows that the calculation results obtained from the improved trailing vortex model are more accurate than those obtained from the old model.

A project is presented which was set up to compare a new method of analysis (for the determination of the dispersed oil content in produced water from oil gas and condensate platforms) with the current OSPAR reference method. The new method is a modification of ISO 9377-2 based on GC-FID (gas chromatography with flame ionisation detection); the current OSPAR reference method is based on IR (infrared spectrophotometry). The decision for this project was taken at the 2002 meeting of the OIC (Offshore Industry Committee) and was based on a small-scale comparison carried out by the Netherlands in 2001. The results of the small-scale programme were presented at the OIW workshop in 2002 in two presentations. In the 2002 project samples from 58 platforms (five countries) were analysed with both methods. A ring test was added to obtain more specific details about the GC-FID performance in the four laboratories involved. Statistical evaluation of all data was done by TNO Environment Energy and Process Innovation the Netherlands and resulted in two reports.

The value of reduced roll motions is well recognised. An efficient roll reduction can be achieved on many types of ships especially on naval ships by using the rudder and the ordinary steering system not only for manoeuvring but also for roll damping. The concept of RRS (rudder roll stabilisation) is discussed. A special design based on adaptive filter and control techniques implemented in a microcomputer is described. Measurements obtained on two Royal Swedish Navy ships one attack craft and one mine layer in beam and stern quartering seas show that roll reductions in the order of 40-60 per cent are obtained using the ordinary steering systems when the RRS-system is switched on. The system which is called ROLL-NIX can easily be installed on both existing ships and new designs. Hit probability helicopter operations and performance of human operators can be improved. In conclusion

Contents Dr Helen Doe, 'The Thames Merchant Yards in the Napoleonic Wars' p.10 Ken McGoverin, 'William Pitcher and the Northfleet Dockyard, 1830-60' p.22 Kevin J Foster, 'Thames Shipyards and Merchants and the American Civil War' p.39 Prof. Janette Rutherford, 'Thames Iron: History of a New Issue' p.73 Stuart Rankin, 'Wo Was the London Engineer?' p.91 Dr Alston Kennerley, 'Civilian Stationary Training Ships and other Mercantile Marine Education on or adjacent to the River Thames' p.104 Peter Webberley, 'Yarrow's Shipbuilding Yard on the Isle of Dogs' p.130 Hugh Lyon, 'The Thames Steamboat Companies' p.148 Dr Roger Owen, 'Fitting-out and Repairs of Early Steamships at the City Canal on the Isle of Dogs' p.159 Ricahrd Hartree, 'John Penn & Sons, Marine Engineers of Greenwich' p.178

A look is taken at ALISTAR 3000 a multipurpose AUV for inspection and survey missions down to 3000m. ALISTAR 3000 is designed to be especially adapted to perform inspection of underwater structures such as pipes but can also carry out survey missions using typically acoustic and optical sensors. This paper presents the performance and main characteristics of the system a description of the vehicle design a description of the solution selected for the energy source and a description of the Mission Management System. Also illustrations are given of typical inspection missions to be carried out by ALISTAR system and the results are provided of the ALISTAR sea trials along with the outlook of coming-up trials.

Thames Shipwrecks: a race against time Lloyd’s Register’s Information Services department recently provided research for Touch Productions on vessels being investigated by Wessex Archaeology in the Thames Estuary. The work was captured in two BBC programmes broadcast on BBC2 on Tuesday August 26 and Tuesday September 2, 2008. This generated enquiries and interest in the Lloyd’s Register reference library in London, from both our employees and the general public. The programmes examined a series of wrecks within the main navigation channels looked after by the Port of London Authority (PLA). This work was prompted by major plans for expansion that include new dredging in existing channels, hence the ‘race against time’ to safeguard the archaeological and historical interest in wrecks that lie in these channels.

Although much work has been undertaken over the last ten years to reduce the impact of shipping on the environment a comprehensive inventory of emissions and discharges is still lacking. This would assist in the assessment of the impact of shipping on the environment of the relative environmental performance of shipping against other modes of transport and of the performance of new legislation technologies and working practices. A review of the current availability of information on the level of emissions and discharges from shipping to the environment is presented. Emissions to air and water and waste streams are considered. It is concluded that information is patchy. Ways forward are suggested.