Fatigue assessment in finite element analysis: A post-processor to FEA output for hot spot stress calculation

For the fatigue assessment of welded structures, several design methods are described by the design codes of IIW, Eurocode3 and DNV. The relation between the stress range and cycles to failures were derived from experiments: the SN curves. With the increased accessibility of finite element software to engineers, a more flexible approach emerged:...

Fatigue Load Model Safety: Verifying Reliability for Reinforced Concrete Railway Structures

It was unclear what level of reliability was provided by appliance of the Eurocode load models for fatigue due to train loads, meaning that it might be insufficient. Therefore, it was investigated what the provided reliability is, compared to what is should be. Within this report, the focus is solely on fatigue induced by bending moments on...

Fatigue and Healing of Asphalt Mortar

Fatigue is one of the common failure mechanisms occurring in asphalt pavements. To better understand the underlying principles of these fatigue mechanisms, a procedure is developed to construct fatigue curves based on tests in uni-axial tension on asphalt mortar, leading to defining fatigue life using a variety of methods. The uni-axial tension...

Prediction of Fatigue Crack Growth behaviour of tubular joints used in offshore structures

The high levels of wind and wave loads on offshore structures make fatigue analysis a significant parameter that has to be taken into consideration throughout an offshore structure design. Steel tubular members are widely used in offshore (wind) industry due to their efficient structural behaviour. The welded connections between the different...

State-of-the-art design methods for wind turbine towers

The costs of wind energy have to be reduced in order to be competitive with conventional methods to generate electricity. The tower costs contribute significantly to the costs of a wind turbine. This thesis aimed to suggest improvements in wind turbine tower design in comparison with industry standards nowadays in order to reduce the costs of...

Fatigue analysis of subsea Jumper under external loads (steady current and earthquake)

In recent times, the oil and gas business has moved into unconventional reservoirs, especially in deep-water. One high-potential prospect was found in the deep-water area of Myanmar. A subsea production system pilot project is planned for implementation in this area. One essential element of a subsea system is a “subsea jumper”. The main...

Interaction between an asphalt revetment and the sand subsoil under wave attacks: Medium scale experiments with old and new asphalt concrete

Nowadays, in the Netherlands there are about 600 kilometers of asphaltic revetments lying mainly on sea dikes of which approximately 400 km of dike is covered with asphalt concrete [STOWA, 2011]. Asphalt concrete revetments are applied the most and are mostly of older age. Because of the older age it needs intensive care involving periodic...

Upgrading Old Movable Bridges with FRP Deck Application: The case study of Wilhelminabrug

Fibre Reinforced Polymer bridge decks, thanks to their beneficial properties and various advantages over traditional materials, have great potential as a material used in bridge engineering. They exercise high specific strength and stiffness-to-weight-ratio, a property particularly interesting from the point of view of designers, as it provides...

Fatigue of steel lock gates

The Netherlands contains more than 400 hydraulic structures, of which 120 are locks. Inspections carried out since 2010 by Rijkswaterstaat revealed that a number of cracks per lock gate have been found. Based on experience and an evaluation of the photos made during the inspections it is assumed that the cracks occur due to fatigue. At this...

Fatigue and shear failure. Differences between NEN and Eurocode.

Within this document the differences arising from the transition of the NEN (Dutch code) to the Eurocode are studied with respect to shear failure and fatigue. These differences are investigated on a global level, where in addition the fib Model Code is taken into account. In the next part the actual differences are determined within a case...

Effect of TIG-dressing on fatigue strength and weld toe geometry of butt welded connections in high strength steel

When high strength steels are applicated in dynamically loaded structures, fatigue problems can arise. In most current design codes, the fatigue strength of high strength steels is either not discussed or determined as similar to mild steels. This assumption can be related to the dominance of the crack propagation life during in the total...

Optimising the Design of a Steel Substructure for Offshore Wind Turbines in Deeper Waters

In the need for more green energy a prominent role is reserved for wind energy. Offshore wind energy in deeper waters capitalises on more efficient wind properties and increased public acceptance compared to onshore wind energy and wind farms close to shore. In the coming years the offshore wind market is expected to evolve rapidly, especially...