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In this study the influence of rate of loading on uplift capacity of piles in clay is experimentally investigated. A model pile having an outside diameter of 30 mm was subjected to axial uplift loads to failure under five different loading rates. In addition consolidated undrained triaxial tests were performed under the same loading rates used in the model pile tests and the corresponding values of the shear strength of the soil were found. Theoretical bearing capacity was calculated based on the shear strength measured in the triaxial tests and compared with the measured bearing capacity under the same loading rate.

Submerged breakwaters are structures built with a crest elevation below the local water level. These submerged breakwaters reduce the incident wave conditions after the wave transport over the breakwater. The incident wave energy is reduced so that the wave run-up height on the sloping dyke is also decreased. Also the roughness of the sloping dyke can decrease the wave run-up height. Here the influence of the offshore submerged breakwater on the wave run up on a triangular step dyke is studied. Results show that the influence of the submerged depth of the submerged breakwater to the wave run up on smooth or step dyke is the biggest factor. The influence of the crest width of trapezoidal submerged breakwater as well as the installed distance of the submerged breakwater to the toe of the dyke for the relative run up height on the dyke surface is small.

An area in the South Minch on the Scottish west coast was surveyed acoustically using the seabed discrimination system RoxAnn. The main purpose of this paper is to examine the effect of track spacing and interpolated pixel size on the interpretation of benthic community distributions. If there are wide variations in the maps produced using different survey track spacings and levels of data interpolation this could have significant consequences for the use of this system as a tool for mapping benthic communities of an important conservation nature. The work presented here investigates different combinations of survey track spacing in relation to interpolation of acoustic data for mapping benthic biodiversity. A look is taken at materials and methods followed by results and discussion.

The simultaneous reduction of PM (particulate matter) and NOx (nitrogen oxides) is an important technical problem for diesel engine researchers. The fuel properties and injection condition have strong effects on soot and NOx formation in a diesel engine. The effects of fuel properties and injection condition on ignition and combustion of intermittent spray were examined experimentally. To examine the effect of fuel properties five types of fuel with different aromatics components were prepared. Fuels were injected into the high temperature and high-pressure vessel and an ICCD camera captured images of spray flames. Two-colour pylometry technique was applied to the images of spray flame and two-dimensional distributions of flame temperature and soot in flame were quantified.

A study to determine the effects of pelagic mysids on the biomass and size-structure of the phytoplankton community during the period following the spring bloom. Mysids excreted phosphate and ammonium and increased the total chlorophyll 'a' concentration of phytoplankton slightly. However the presence of mysids affected different size-classes of phytoplankton differently. Mysids mainly grazed on large-sized phytoplankton cells. Small-sized algal cells avoided grazing gained a competitive advantage and were able to utilise the nutrients excreted by mysids.

In this paper the deformability of a high grade linepipe subjected to an axial compressive force is experimentally and analytically discussed. Four cases of axial compression experiments using high grade linepipes with high yield-to-tensile ratio were carried out and an appropriate finite element analysis method for estimation of the deformability of linepipe was established. By using the finite element analysis parametric studies were then conducted to clarify effects of the diameter-to-thickness ratio (D/t) yield stress tensile strength Y/T and the shape of the stressstrain curve on the compressive deformation behaviour of the linepipe. Finally the effects of pipe geometry and mechanical properties on the deformability of the high grade linepipe were examined.

A high speed towed vehicle "Flying Fish" is being developed to measure chemical and physical properties of the ocean. To design a motion control system for the vehicle an accurate mathematical model of motion of the towing cable is essential because the cable length must be very long to meet safety requirements and to expand the observation area. In this paper a technique is reported for design of a motion controller which uses a mathematical model based on mode expansion by eigenfunctions. This provides an accurate mathematical model of the cable motion which has fewer parameters than other methods. Accuracy of the cable model is investigated by numerical simulation and field experiments and a motion controller for the towed vehicle is designed based on this model.

Part 1 of the book deals with the question of the various types of energy available at time of publication and in the future, for power generation on a world-wide basis. The energy sources covered are: petroleum, natural gas, coal and nuclear power. Part 2 deals with the subject of ships and examines the effects of energy on existing and future ship designs, looking at developments and adaptations in ship design, propulsion, automation and manning.

The NOAA Ocean Service's Centre for Operational Oceanographic Products and Services (NOS/CO-OPS) operates Physical Oceanographic Real Time Systems (PORTS) at many major sea ports to provide real-time information in support of safe and efficient maritime commerce. CO-OPS recently added current profiling systems mounted on existing US Coast Guard aids-to-navigation (ATON) buoys to the suite of operational PORTS sensor systems. This development work was undertaken in order to widen the operating area and improve the reliability of PORTS current measurements. The progress of efforts to improve both the quality of data and the offshore operating range of a current measurement system mounted on US Coast Guard navigation buoys is reported.

In some locations ice covered waters overlap with earthquake zones where ice-resistant and seismic offshore structures are required. Earthquakes often occur in wintertime and offshore structures suffer both due to ice and seismic loads. One of the important but uncertain designs conditions for fixed offshore structures constructed in ice-covered waters may be the seismic load. In order to clarify the effect of earthquake on the behaviour of offshore structures in ice-covered waters analyses and experiments have been performed as a research project of the Japan Ocean Industries Association. Analyses and experiments have been performed to investigate the behaviour of a platform under both ice and earthquake conditions. This paper presents the results of the research obtained so far. The results are being used in the preparation of guidelines on the seismic design of offshore structures in ice-covered waters.

An experimental study is conducted to investigate the response of an ice-surrounded structure during an earthquake by using an underwater shaking table. The interaction of an ice-surrounded structure with the soft and dense foundation and the dynamic reciprocal motion of the structure caused by an ice floe motion is investigated. It is found that the ice-surrounded structure on a dense foundation has sliding and locking motion occurred during shaking whereas on a soft foundation the displacement of the ice-surrounded structure is larger. In addition a numerical analysis is carried out using FLIP (finite element analysis of liquefaction program). The objective of this analysis is to validate FLIP for the calculation of the response of ice-surrounded structures during earthquake motions. This paper describes the results of both the experimental and the numerical analyses of an ice-surrounded structure subjected to earthquake motions.

A lot of research has been done in the past on flows over cavities but the concept of flows over submerged cavities having free surface is relatively a new idea. Cavity flow phenomena occur in a variety of structures. The presence of cavities can give rise to drastic changes in the steady and unsteady loading character of these structures where pressure fluctuations can be so intense that they can lead to fatigue and structural failure. This paper focuses on understanding the hydrodynamic characteristics of flow across submerged cavities with free surface. A flow noise experiment was investigated in a towing tank with the help of the empirical mode decomposition method.

Small passenger vessels frequently operate close to much larger ships particularly in ports and on inland waterways. The smaller vessels' operations often take them across main shipping routes where large vessels operate with restricted ability to manoeuvre. There is a potential risk for a small passenger vessel to be struck by a larger ship. A modest series of model tests is described carried out to study the mechanisms involved and the potential for flooding or capsize. The aim is to attempt to establish the parameters affecting the survivability of passenger vessels in terms of design parameters or stability characteristics. Models of two monohulls and a catamaran were subjected to collisions while stationary in a towing tank. The impact location relative headings speed model configuration and stability were varied. The results showed that for each configuration a critical collision speed could be established above which sinking or capsize would result. Comparison of the critical speeds enabled the relative safety of each configuration to be assessed. Stability and freeboard were found to have an influence on the critical speed and the work provided some valuable information regarding the stability characteristics and behaviour of these vessels.

Knowledge is required of the effect of sea loads on the structure of lightweight high-speed vessels in order to optimise their structural design. An investigation into the response of a 96 m Incat high-speed catamaran to an extreme slam event which occurred whilst extensive full-scale hull stress motion and wave measurements were being carried out on the vessel during regular ferry services. The strain gauge data from the full-scale slam events has been used in conjunction with a refined finite element model to develop a realistic asymmetric slam-loading scenario for structural design purposes. This slam load case has been compared with DNV (Det Norske Veritas) classification rules and a method for scaling the load case for use with other large wave-piercer catamaran designs is proposed.

As the HSLC (high-speed light craft) market continues to expand to include ever-larger vessels the critical design loads move from local hull and deck pressures to global wave-induced loads. Global hull stresses and dynamic stresses due to slamming events are now the focus of design improvement. A project is described which established the full-scale global sea-loads acting on an 86 m Austal Ships high-speed catamaran ferry. To achieve this full-scale wave motion and hull strain measurements were taken onboard the vessel. The results of the experimental programme are presented. An existing global Finite Element model of the vessel has been further developed for this project and the full-scale measured strain data will be used to reverse engineer the global sea loads acting on the vessel. The results of the experimental programme will be compared to theoretical predictions from a non-linear ship hydrodynamic response code. The sea-loads will be compared to rule sea-loads calculated according to Germanischer Lloyd design rules.

Offshore operators are required by law to report to the HSE (Health and Safety Executive) all incidents involving hydrocarbon fires explosions and unignited releases which occur on their installations. These reports together with additional voluntary information on such incidents provided by the operators are collated and analysed by HSE. Summaries of the data are published each year. An HSE initiative is presented which aims to reduce the number of hydrocarbon releases offshore by 50% in three years. The programme is described followed by a 10-element inspection project and an investigation project to identify where things are going wrong and allowing leaks to occur. The response of industry to the initiative is described and the results so far are outlined. Annexe 1 lists the main components of the process integrity inspection topics (pp 2.1.7- 2.1.9) followed by graphs showing hydrocarbon releases pp 2.1.10- 2.1.11).

The present paper contains results of an experimental study on a semi-planing catamaran. The aim of this study is to find the effect of hydrofoil usage on resistance of semi-planing catamaran and achieving optimal attack angle arrangement of hydrofoils and displacement centre of gravity. Tests have been done without and with hydrofoils in certain arrangement with different angles of attack and the results are compared. Results show considerable resistance reduction obtained in semi-planing vessels equipped with hydrofoil in optimized angle of attack in service speed range. Meanwhile the hydrofoils arrangement and the angle of attack are important so unsuitable design causes the instability in the motion and maybe increases hydrodynamic resistance.

Research was carried out by the Environment Monitoring Department to recognise and control the impact of the Jaworzno municipal landfill impact on the quality of underground water in the north-eastern part of the GZWP Chrzanov in Poland. The underground and surface water of the municipal landfill area was monitored and the water was found to have a tenfold increase in lead content. The lead content and environmental and geological data were considered. The lead content was correlated with the extremely low level of underground water. Based on the geo-chemical test results it was concluded that the increased content of lead in the underground water was probably related to oxidisation of ore materials that appear naturally in Triassic dolomites and contain lead. Normally the lead would have been underwater and hardly soluble but lower water levels had meant that the lead was out of water and the air had made it easily soluble resulting in a sudden increase in the lead content of drinking water. Results are presented and discussed.

There is strong experimental evidence to suggest that mammals process sound coherently. The impact of signal coherence from active sonar systems on marine mammal behaviour is investigated. The objective is to prove that the amplitude of the emitted pulse alone is not the only signal parameter impacting marine mammal behaviour but that the signal coherence properties of the propagated wave form at the marine mammals' location may be related to the so-called 'irritability index'. Two phases are described. The first describes experiments in designing transmitted waveforms. The second describes the running of a full wave acoustic model FEPE (finite element parabolic equation) to assess coherence properties of propagated energy at the mammal. Results of the impact of active sonar signal coherence properties on marine mammal behaviour as measured by the index of irritability are given. With the data of which waveforms irritate or harm marine mammals a tool will be designed that will tell the 53C operator how to transmit in a specific shallow water environment in a manner both safe for marine mammals and effective for ASW.

One of the most interesting emissions from marine power plants is nitric oxide. Oxides of nitrogen grouped as NOx are produced from the nitric oxide generated during the combustion process in engines and boilers. The production of nitric oxide depends on the combustion temperature. Hence NOx is a function of engine loading in most engines. Organic nitrogen such as in protein increase the production of nitric oxide during combustion. Although many fuels burned by marine engines and boilers are not expected to be high in nitrogen there is still concern that fuel-borne nitrogen is making a substantial contribution to pollution from ships. Stack emissions are examined together with fuel data taken from a large number of ships operating at steady state. Since the stack emissions data include nitric oxide emissions and the fuel analyses include fixed nitrogen in the fuel these data can be used to determine whether the effect of nitrogen in the fuel has a significant impact on oxides of nitrogen in the exhaust emissions. Results are presented and discussed and conclusions drawn.