ABSTRACT An experimental investigation has been undertaken to determine the effects of fatigue on the high strain-rate material properties of high-performance steel used in modern naval vessel structures. A novel methodology to conduct tensile testing at low and high strain-rates on fatigued specimens was developed. A bespoke Split Hopkinson’s Tension Bar clamping arrangement was designed to undertake

ABSTRACT The commonly used acrylic frustum windows are the weakest components in the deep-sea manned cabin of the submersible. The short-term collapse test is typically required by full or scale model test, which can applied to measure the critical pressure but cannot tell when the structure begins to damage and how the damage continues. To make up for the deficiency, it is necessary to develop the

ABSTRACT The load response characteristics of VLFS in oblique waves have very important impact on the structure safety assessment of VLFS. However, due to the complexity of the truss-type VLFS structure, the only research achievements focus on the box-typed VLFS. Thus, a simplified time-domain nonlinear hydroelastic method for a truss-type VLFS is developed. In the structure part, according to the

ABSTRACT The numerical study presented in Part I (Gaggero, 2020), focused on the prediction of the laminar-to-turbulent boundary layer transition on model scale propellers, is extended to cavitating conditions. In the previous study, the application of the γ-Reθ Local Correlation Transition Model allowed for significant improvements in model scale performance prediction and highlighted the role of

ABSTRACT The influence of the laminar-to-turbulent boundary layer transition on model scale propellers characteristics is investigated using the γ-Reθ model. OpenFOAM and StarCCM+ RANSE solversare used for the investigation, which is carried out for two test cases. Available measurements at a sufficiently low rate of shaft revolution (i.e. Reynolds number)are used to assess the capabilities of the

ABSTRACT The nonlinear dynamic behaviour of steep wave riser (SWR) subjected to the top harmonic motions considering the effect of the internal flow is numerically investigated using a three-dimensional (3D) time-domain finite element method (FEM) based on the slender flexible rod theory. In this numerical model, the riser which satisfies geometric nonlinearity is divided into three segments: decline

ABSTRACT The plastic dynamic response and failure modes of ship broadside protection structures (SBPSs) subjected to contacted underwater explosion (UNDEX) are investigated. A novel engineering analytical model is proposed to evaluate the failure mechanisms and energy absorption characteristics. A numerical model considering the fluid-structure interaction (FSI) is built to analyze the plastic dynamic

ABSTRACT Inspection is a key aspect of any structural maintenance programme, including that of ship and offshore structures with a long-lasting history of service failures. Ship surveys for construction, verification, repair and conversion are intrinsically hazardous that are mainly performed by human surveyors. The ROBINS project (ROBotics technology for INspection of Ships) is an EU Horizon 2020

ABSTRACT The artificial island project of the Hong Kong-Zhuhai-Macao Bridge includes the island construction project, the island part at the junction of the island and the tunnel, and the transition section between the island and the tunnel. The bearing capacity and deformation characteristics of the compacted sand pile composite foundation are studied through the load test of underwater compacted

ABSTRACT ibreglass reinforced flexible pipe (FGRFP) is a kind of composite thermoplastic pipe serving as a preferred application in the field of oil transportation. This paper studies the mechanical behaviour of FGRFPs under pure bending by experimental, numerical and theoretical methods. Full-scale four-point bending tests are conducted and the curvature-bending moment relations of specimens are recorded

ABSTRACT The application of data mining techniques is an extended practice in numerous domains; however, within the context of maritime inspections, the aforementioned methods are rarely applied. Thus, the application of data-mining techniques for the prediction and ranking of non-conformities identified during vessel inspections could be of significant managerial contribution to the safety of shipping

(2020). A Pioneer of Computational Welding Mechanics and Ultimate Strength Analysis (ISUM). Ships and Offshore Structures. Ahead of Print.

ABSTRACT This study experimentally investigated the performance and hydrodynamic response of a flexible floating pontoon-type breakwater. The floating breakwater consists of ten rubber pontoons with flexible connections. The effect of relative breadth and relative wave height on the wave transmission, reflection and dissipation coefficients has been discussed for various assembly configurations of

(2020). A Pioneer of Ship Collision and Grounding. Ships and Offshore Structures. Ahead of Print.

(2020). A Pioneer of Computer-Aided Ship Structural Design. Ships and Offshore Structures. Ahead of Print.

ABSTRACT Flexible risers that for deep-water production are designed with strong collapse capacity. However, this collapse capacity is susceptible to pipe curvature in the flooded annulus condition. For the curved riser sections within the touchdown zone, significant reduction of collapse capacity can occur once the external sheaths are worn out, resulting in the so-called ‘wet collapse’. Therefore

ABSTRACT A new type of two-module semi-submersible offshore platform has been designed as an offshore floating base for scientific research and environment measurement. The platform consists of two identical configuration semi-submersible modules which are connected with hinge-like connectors. Experimental and numerical studies in both frequency and time domain were carried out to investigate the coupled

ABSTRACT In this study, the Local Joint Flexibility (LJF) of tubular T/Y-joints with doubler plate under in-plane bending (IPB) load is investigated. In the first step, a finite element (FE) model was developed and verified using the available experimental results. In the next step, 252 FE models were generated to investigate the effect of the joint geometry on the LJF factor (f LJF). Results showed

ABSTRACT Experimental tests are an important source of information for the design of floating production systems. Worldwide, there are few ocean basins with capabilities to reproduce ultra-deep-water scenarios, and they are characterised by having large dimensions. Even so, an equivalent truncated mooring/riser system has to be used. It is a technological challenge to reproduce with a truncated mooring

ABSTRACT The bucket foundation is a new type foundation which is suitable for offshore wind turbines. The failure envelope is used to check the bearing capacity under combined loading conditions, especially for foundations with irregular shapes. Due to the coupling effect between horizontal and moment loads, the H-M failure envelope has an obvious asymmetry, which makes the established algebraic equation

ABSTRACT Previous statistical maritime accident studies are focused on identifying human factors. However, the previous studies were not capable of modelling the complex interrelations that exist between these factors. As accidents are complex processes, researchers fail to agree on the contribution of each human factor. Therefore, in this research study, a new Fuzzy Cognitive Map (FCM)-based technique

ABSTRACT The operational costs of ship recycling yards will increase since the new regulations require more stringent standards for preserving the occupational and environmental health and safety of the people involved in recycling activities. Improvement of the current operational procedures and current levels of productivity will be critical to survive in a competitive industry dominated by low-cost

ABSTRACT The large diameter deep inserted steel cylinder is used for the first time in the artificial island project of Hong Kong-Zhuhai-Macao Bridge. Through the ingenious conception of the scheme of large diameter deep inserted steel cylinder, this paper analyzes the working mechanism, design key points and construction key points of large diameter deep inserted steel cylinder structure, and introduces

ABSTRACT The attenuation of the incident wave interacting with a very large floating structure (VLFS) in the presence of vertical barriers is analysed considering small amplitude wave theory. The VLFS is considered to be articulated and is modelled based on Timoshenko-Mindlin plate theory. The eigenfunction expansion method along with the orthogonal mode-coupling relation is employed for the case of

ABSTRACT This study investigated the free hydroforming of a stainless-steel egg-shaped shell. An egg-shaped shell is a promising geometry for deep pressure hulls. The length and width of the egg-shaped shell were 512.40 and 356.25 mm, respectively. The wall thickness of the egg-shaped shell were 0.844 mm. The equivalent stress, yielding load, internal capacity, and surface area of the egg-shaped shell

ABSTRACT Pipeline installation into deep waters puts higher demands for the laying design. To reveal pipelay parametric effects on the pipeline dynamic behaviours, this study developed a dedicated finite element model (FEM) for deepwater S-lay system in light of OrcaFlex. This FEM sufficiently considered the clashing contacts between the pipeline and stinger rollers as well as pipe-seabed interactions

ABSTRACT When the external load exceeds the ultimate strength of hull girder, the load-carrying capacity is not completely lost due to the supporting and constraint between structure members. It is also determined by the post-ultimate strength behaviour, and the collapse severity needs to be studied to evaluate the consequence of collapse. An analytic approach is presented in this paper to analyse

ABSTRACT A path following control strategy is proposed for the guide ship in the underway replenishment without velocity measurements. Firstly, the detailed models of the ship and external disturbances are established. Secondly, an extended state observer is designed to estimate the linear speeds and yaw rate of the ship based on the information of position, heading, propeller speed and rudder angle

ABSTRACT As ocean engineering has developed towards the deep sea, a precise instrument is urgently needed to accurately measure the in situ strength of soft clay at the shallow strata of the deep sea and thus to evaluate the bearing capacity of the foundation. In this paper, a new type of probe – the strip probe – is introduced. The soft clay failure modes, including the shallow penetration and deep

ABSTRACT In this paper, we present an extension of the alternative environmental contour approach based on inverse first-order reliability theory in a three-dimensional model that accounts for short-term extreme response uncertainties. Subsequently, the long-term extreme tension under wave excitation loads is investigated to evaluate return levels for the design of mooring systems. Tension extreme

ABSTRACT Given the particularity of the environment of the immersed tunnel, once damage occurs by earthquake, it will cause catastrophic consequences. Therefore, it is necessary to evaluate the seismic performance of immersed tunnel. To study the seismic response law of immersed tube tunnels under different site conditions and seismic wave input directions, we tested four groups of immersed tube tunnel

ABSTRACT The paper presents experiments and finite element simulations of welded aluminium-alloy 5083-H111 plates under near-field air-blast loadings to examine their dynamic plastic deformation and failure. The material degradation takes place in the heat-affected zone affecting the failure mode of aluminium plates. Five specimens are assessed, one bare plate and four butt-welded plates. The effect

ABSTRACT Design criteria, and risk evaluation for marine structures, over continental shelf and slope might be affected by currents associated with internal waves. The derivation of design criteria requires long time series of currents at very high sampling rates commonly not available. Therefore, methodologies to derive those time series are required. In this paper, an approach based on numerical

ABSTRACT In the scientific community, water entry impact study has been remained focus by various authors across the globe in past decades. This paper reviews different analytical, experimental and numerical techniques for water entry impact problem. In this article, water entry problems have been broadly categorised into two main groups i.e. water entry of wedges (focusing on hull slamming loads only)

ABSTRACT Maritime transport is one of the most popular means to convey goods over long distances. The relationship between the weight of the transported cargo and the fuel consumption makes maritime transport a very economical solution in relation to other means of transport. However, the great popularity of this type of transport is having consequences, as the significant amount of greenhouse gas

ABSTRACT The present paper continues the recent works reported by Liu et al. (2020 LiuB, LiuK, VillavicencioR, DongA, Guedes SoaresC. 2020. Experimental and numerical analysis of the penetration of welded aluminium alloy panels. Ships Offshore Struct. DOI:10.1080/17445302.2020.1736856.[Taylor & Francis Online], [Web of Science ®] , [Google Scholar]) where quasi-static indentation experiments and finite

ABSTRACT This study deals with the probability distribution of fatigue damage of the mooring system for offshore fish cage considering the uncertainty of long-term wave conditions. A set of numerical simulations for offshore fish cage are performed to predict the fatigue damage of the mooring system. Through a virtual stochastic process model, the probability density function of the long-term fatigue

ABSTRACT Dynamics of damaged ships has repelled close attention until the 1980s, following ground shaking accidents (Herald of Free Enterprise, 1987 and Estonia, 1994). Research since then continues unabated, in the knowledge that damage stability is responsible for 90% of deaths in the maritime industry. Notwithstanding this, safety even in the most advanced maritime nations is still being perceived

ABSTRACT Hydrocarbons are produced offshore in more than 50 countries and contributed about a quarter of world production c.2020, slightly more for crude oil and slightly less for natural gas. All oil and gas projects involve technical, environmental, economic, and financial challenges, but offshore projects are especially sensitive to these factors and often require advanced engineering and innovative

ABSTRACT A novel approach is proposed for the reliability estimation of jacket-type offshore platforms excited by dynamic loadings (wave and seismic) applied in time domain. The information on risk is extracted with the help of multiple finite element-based deterministic analyses. This feature is expected to be attractive to practitioners for routine applications without advanced expertise in the risk-based

ABSTRACT The paper presents a method for the assessment of residual strength of a ship hull damaged in a grounding accident. The strength assessment is based on a coupled beam (CB) method that allows time-efficient analysis. As a case study the method is applied to a double hull tanker. Three grounding damages are defined based on IACS guidelines and with a dedicated grounding assessment tool. The

ABSTRACT It is desirable for naval architectures to simultaneously bear high force and dissipate dynamic energy. A structural protection approach via a specifically designed all-metal stiffened member with bistable components is proposed, which not only exhibits high stiffness but also an order of magnitude increase in the structural damping compared to that of a traditional member under wave impact

ABSTRACT The efficient management of marine vessels ensures that ships could operate smoothly and navigate at the most efficient level. Thus, the environmentally friendly voyage realises with the optimised running cost. Such a management approach could be achieved via a planned and proper maintenance strategy on the critical parts of the marine vessels’ combustion engines. Accordingly, in this study

ABSTRACT In this study, free vibration analysis of cracked plates was performed by using peridynamics (PD). A peridynamic Mindlin plate formulation was used and the numerical implementation was done using commercial finite element software, ANSYS. First, the formulation was verified by considering intact and cracked plates and peridynamic solutions were compared against numerical, theoretical and experimental

ABSTRACT A simple dynamic positioning (DP) system has been developed for the scaled model of a novel twin-lift decommissioning operation. Such a decommissioning solution involves the two semi-submerged vessels transporting the topside to another vessel. And it requires the synchronised motion of the two topside-carried vessels at a low speed, under the environmental disturbances. In order to ensure

ABSTRACT Design and fabrication procedures used in spherical pressure hull construction have been described in this paper. An appropriate design standard has been applied to ensure the safety and reliability of the pressure hull. Considering the material and manufacturing facility available, steel has been chosen as the pressure hull material. Design and manufacturing of spherical pressure hull have

ABSTRACT A commonly assumed ship-to-ship collision scenario is a rigid ship bow hitting the side of a ship perpendicularly. A bulbous bow has a slender shape overall but a rounded end, while a stem has a sharp horizontal edge but a gently sloping body. It was found from numerical simulations that the stem collision induces horizontal shear failure on side shell as soon as the stem contacts with the

ABSTRACT A CFD-based adjoint solver tool is presented to modify the hullform of a trimaran ship. Cost function of optimization process is considered total for resistance of trimaran at cruise speed. Mesh sensitivity gives sensitivity of the cost function associated with mesh deformation. Mesh morphing tool is implemented to alter the geometry without the need to revisit the CAD environment. The position

ABSTRACT Liquefied natural gas (LNG) exhibits significant environmental advantages. However, the hazards of LNG-fuelled ships need to be investigated in their early design stages, particularly with regard to accidental fuel leakage. In this study, a hypothetical oil tanker model was used with a fuel gas supply system installed on the main deck; the objective was to establish a critical zone for natural

ABSTRACT An experimental programme and nonlinear finite element analysis are carried out to examine the ultimate strength characteristics of stiffened panels with a crack and pits, under uni-axial longitudinal compressive loads. The test results are used to validate the finite element models. A series of nonlinear finite element analysis is performed with the validated models to illustrate the ultimate

ABSTRACT Sideline is a key component of fish sensory system, which has been found to affect many behaviours of fish, including manoeuvring obstacle avoidance, prey tracking and environmental mapping in complex fluid environment. In this paper, based on the sensing flow field mechanism of fish lateral line system, a sphere obstacle model is established by using the CFD method and FLUENT software, and

ABSTRACT A numerical model was proposed to analyse the combined effect of the pneumatic breakwater and the submerged breakwater for improving the wave damping performance, in which the Reynolds Averaged Navier-Stokes equations combined with the Shear Stress Transport (SST) k-ω turbulence model were adopted to investigate the flow field. A series of existing experiments were applied to validate the

ABSTRACT The scattering of surface gravity waves by a skirt wall breakwater is analysed in two dimensions under the assumption of small-amplitude wave theory. The oscillatory wave past the porous skirt walls is assumed to follow Darcy’s law. The boundary value problem is solved using multi-domain boundary element method to obtain the numerical results for the different number of porous skirt walls

ABSTRACT Flexible risers are composite cylindrical structures, which are widely used in offshore oil and gas production facilities. Failure of a flexible riser during operation causes major economic and environmental losses. The improvement of structural integrity programs based on nondestructive techniques and risk-based inspections is therefore utterly important. In this article, the feasibility

ABSTRACT A numerical analysis and experimental validation of sloshing phenomenon in three-dimensional square tank with varying resonant frequency and amplitude of excitation is carried out in this study. Numerical simulations using fluid-structure interaction (FSI) was carried out and validated with experimental result. Square tank is numerically simulated with 50, 100 and 200 mm of water height excited

ABSTRACT A precise estimation of the welding deformation is an essential process in improving steel fabrication processes for building ships and offshore structures. This study validated the effect of the optimal simultaneous welding on the mitigation of welding displacements. Most previous studies on the optimised welding sequence for the reducing welding displacements have focused on one welding

Oceanographic research vessels (ORVs) are used to collect ocean data and analyse them to understand the physical, chemical and biological characteristics of seawater, seabed and other ocean-related factors affecting climate changes. These task require vessel to track a predefined trajectory at different speeds. It is crucial to understand the effect of different speed on manoeuvring characteristics

In this study, the genetic algorithm (GA) was implemented for the multi-objective optimization of the structural design of a pressure hull. The objective functions sought the maximum ultimate strength of the ring-stiffened cylindrical shell structure with minimum structural weight and maximum volume of the configured structural member. First, the evaluation models of several design variables of submarine

Energy efficient and environmentally friendly shipping have been primary concerns for the maritime industry. One of the alternatives to overcome these issues onboard is organic Rankine cycle (ORC) waste heat recovery system (WHRS). In this study, a transcritical ORC WHRS for a marine diesel engine is investigated at different engine operating loads by thermodynamic and environmental analysis. The engine

The problem of oblique water wave diffraction by three asymmetrically arranged vertical porous barriers with different widths in infinitely deep water is investigated. Reflection and transmission coefficients are evaluated, applying single-term Galerkin approximation. The amount of energy loss is derived employing Green's integral theorem. Wave force is determined using the linear Bernoulli equation