Influence of Scour Protection on the Vertical Bearing Behaviour of Monopiles in Sand

Extensive studies have been performed on the effectiveness of scour protection against scour erosion progression. But there is little research to date evaluating the effect of scour protection on vertical resistance behaviour of monopile foundations. This paper investigates the influence of scour protection on the vertical loading behaviour of...

Scour Effect on the Lateral Bearing Behaviour of Monopiles Considering Different Slenderness Ratios

Scour leads to the loss of soil around monopile foundations for offshore wind turbines, which affects their structural safety. In this paper, the effect of scour on the lateral behaviour of monopiles was extensively investigated using finite element analysis, and calibration and comparison were undertaken using centrifuge tests. Piles with three...

Surrogate models to unlock the optimal design of stiffened panels accounting for ultimate strength reduction due to welding residual stress

In this paper, for the first time, a three-step approach for the optimal design of stiffened panels accounting for the ultimate limit state due to welding residual stress is developed. First, authors rely on state-of-the-art analytical approaches coupled with recently data-driven nonlinear finite element methods surrogates characterized by...

Computationally aware estimation of ultimate strength reduction of stiffened panels caused by welding residual stress: From finite element to data-driven methods

Ultimate limit state (ULS) assessment examines the maximum load-carrying capacity of structures considering inelastic buckling failure. Contrary to the traditional allowable stress principle which is mainly based on experiences, the ULS assessment focuses on explicitly evaluating the structural safety margin and thus enables a consistent...

Strain partitioning and damage initiation in a continuously cooled carbide free bainitic steel

Microscopic stress and strain partitioning control the mechanical and damage behavior of multiphase steels. Using a combined numerical and experimental approach, local strain distributions and deformation localization are characterized in a carbide free bainitic steel produced by continuous cooling. The microstructure of the steel consists of...

External surface cracked offshore pipes reinforced with composite repair system: A numerical analysis

This paper conducts a numerical analysis on the external surface cracked steel pipes reinforced with Composite Repair System. A three-dimensional finite element (FE) model is developed to calculate the Stress Intensity Factor (SIF) of the surface crack, and the crack growth process is evaluated by the Paris’ law. The effect of FRP-to-steel...

Rational hyperelastic modelling of elastic poured compound for the failure analysis of embedded rail system

The continuous homogeneous rail constraint of embedded rail system (ERS) is realized by the encapsulation of rails with the elastic poured compound (EPC) which is a composite material. Previous treatment of EPC as linear elastic material was insufficient in the failure analysis of ERS. In this work, a hyperelastic model is developed to...

Surface Crack Growth in Metallic Pipes Reinforced with Composite Repair System

Surface cracks are serious threats to the structural integrity of offshore metallic pipes. This dissertation proposes a protocol of composite reinforcement on surface cracked metallic pipes subjected to cyclic loads, aiming to decrease the crack growth rate and prolong the residual fatigue life. The main objective of this dissertation is to...

Numerical investigation on the surface crack growth in FRP-reinforced steel plates subjected to tension

In this paper, we analyse the surface crack growth in the Fibre-Reinforced Polymer (FRP) reinforced steel plates subjected to tension by means of the finite element (FE) method. Following the experimental study, a three-dimensional FE model is developed to evaluate the Stress Intensity Factor (SIF) of the surface crack, and the crack growth...

Development of an analytical model for a special design asynchronous motor

Electrical motors have been widely used in various fields for hundreds of years. The asynchronous motor is always an interesting topic due to its advantage of the simple structure, robustness, low maintenance cost and long lifetime. In this research, a special structure rotor is used instead of the classical squirrel cage rotor. To understand...

Numerical analysis on the SIF of internal surface cracks in steel pipes reinforced with CRS subjected to bending

In this paper, Composite Repair System (CRS) is applied to repair the circumferential internal surface cracked steel pipes subjected to bending. The Stress Intensity Factor (SIF) is quantitatively analysed by means of numerical simulations, and the crack growth rate is predicted by using the Paris’ law. First, the three-dimensional finite...

Numerical investigation of the SIFs of the external surface crack in rigid pipe reinforced with FRP

Fatigue is one of the major challenges of offshore rigid pipes. The surface crack is the main manifestation. Fatigue cracks are evolved from surface cracks which are frequently appear in the external surface of rigid pipes. Under fatigue loads, the surface cracks may continue to propagate and finally develop into penetrated cracks, which may...

Non-intrusive Reliability Analysis of Multi-layered Slopes in Spatially Variable Soils

Stochastic finite element method and random finite element method can provide rigorous tools for slope reliability analysis incorporating spatial variability of soil properties. However, both of them are difficult to be applied into practice due to the modification of finite-element codes and the low efficiency, respectively. To address these...

Computation of the flash-temperature at the wheel-rail contact using a 3D finite element model and its comparison with analytical methods

The coupled mechanical–thermal behaviour of wheel and rail materials under rolling contact is studied to determine the temperature rise due to the frictional heat. The wheel–rail frictional rolling contact problem is solved using the three–dimensional finite element (FE) method. The FE model considers the wheel tread–rail top contact with...

The Vector Form Intrinsic Finite Element method and several other form-finding methods for general networks

Discrete networks is a kind of form-active structural system which actively change its shape under varying load conditions. And for this kind of structural system, form-finding is the initial and essential part in their design process. Before the computer age, people complete the form-finding process using physical models, while with the...

Residual fatigue life evaluation of rail at squats seeds using 3D explicit finite element analysis

A modeling procedure to predict the residual fatigue life of rail at squats seeds is developed in this article. Two models are involved: a 3D explicit Finite Element (FE) model to compute the stress and strain at squats in rail, and the J-S fatigue damage model to determine the residual fatigue life on the basis of the computed stress and strain...