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...

Computational Modeling of Progressive Failure in FRP Composite Laminates Subjected to Static and Impact Transverse loading

In order to arrive at safe and reliable design of composite structures, understanding of the mechanisms and mechanics of damage growth in these materials is of paramount significance. Numerical models, if designed, implemented and used carefully, can be helpful not only to understand the mechanisms and mechanics of damage growth but also to...

Limit analysis discussion of design methods for fracture of timber dowel joints loaded perpendicular to grain

The results of an investigation of splitting of joints of [1] are used for a discussion of design methods and as necessary answer on comments and for confirmation of the extended fracture mechanics theory which accounts for the part of the external energy which is needed for plastic dissipation at the dowels, (which cause the crack opening). It...

On Introducing Imperfection in the Non-Linear Analysis of Buckling of Thin Shell Structures

This master thesis details the investigation of the effect of geometrical imperfection on thin shell structures using general FEM software packages. The author proposes a finite element based method for the analysis and design of thin shell structures, and describes the implementation of such a procedure on four different FEM packages. 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...

Material model for wood

Wood is highly anisotropic and shows ductile behaviour in compression and brittle behaviour in tension and shear where both failure modes can occur simultaneously. A 3D material model for wood based on the concepts of continuum damage mechanics was developed. A material subroutine containing the developed model was implemented into a standard FE...

Open source engineering and sustainability tools for the built environment

This paper presents two novel open source software developments for design and engineering in the built environment. The first development, called “sustainability-open” [1], aims on providing open source design, analysis and assessment software source code for (environmental) performance of buildings, structures and infrastructure. The aim of...

StructuralComponents: A client-server software architecture for FEM-based structural design exploration

StructuralComponents allows an engineer to quickly compose an early-stage structural concept and immediately analyse its performance. It follows the Conceptual Story method in an attempt to deal with imprecision and uncertainty. This thesis represents the third in a series of MSc theses on StructuralComponents, which as its general problem...

Detection of early squats by axle box acceleration

This thesis discusses a new method for detection of short track irregularities, particularly squats, with axle box acceleration (ABA) measurements. A squat is a surface initiated short track defect, associated with high frequency vibrations of the wheel-rail system. High stresses in the contact patch at squats cause accumulation of plastic...

Computational modelling of fibre-reinforced cementitious composites: An analysis of discrete and mesh-independent techniques

Failure patterns and mechanical behaviour of high performance fibre-reinforced cementitious composites depend to a large extent on the distribution of fibres within a specimen. A discrete treatment of fibres enables us to study the influence of various fibre distributions on the mechanical properties of the material. The numerical analysis of...

FEM modeling of fiber reinforced composites: The use of GFEM, the embedded reinforcement approach including bond slip and the "Interface GFEM" approach

Recently several studies have been performed at the TUDelft on the use of the generalized finite element method (GFEM) to model fiber reinforced composite materials in a two dimensional space. The GFEM model allows a large number of arbitrarily placed fibers to be taken into account. The fibers are placed on top of the ordinary mesh and...

Constitutive model for wood based on continuum damage mechanics