Applicability of the Fatigue Damage Sensor in a Structural Health Monitoring System: Sensor fatigue characteristics and lifetime estimates

'Towards a Proper Understanding of Fatigue Crack Growth and Crack Closure

Conventional theories to describe and predict FCG are based on a SIF parameter, ΔK. If ΔK is used as similitude parameter to predict FCG, an R-effect arises. This R-effect can be accounted for by means of plasticity induced crack closure: A plastic wake behind the crack tip causes the crack to close before a zero tensile load is applied. As such...

On Dynamic Fatigue Loads on Composite Downlines in Offshore Service

Offshore oil & gas production is an industry where breaking records has become a necessity. So-called unconventional oil in ultra-deep water (2000 m+) requires rethinking of current production techniques, as steel tubing begins to buckle under its own weight. Other problems arise from corrosion of pipelines at all depths, requiring expensive...

Multiaxial Fatigue due to Wave Induced Accelerations in a Flex-lay Tower Structure

Marine and offshore structures are continuously exposed to different loading types. Cyclic loads results in cyclic stresses in structural components, which may result in degradation of the structural integrity. This process is called fatigue. Fatigue damage of structural components usually occurs without any —global— visible sign. Ultimately,...

Stress Intensity Factors for Fatigue Crack Growth Analysis

Fatigue loads and failures in metallic structures are a well-known technical problem. Commonly, the fatigue life of the steel elements is determined by an analytical calculation using S-N curves as design resistance to periodic action. However, the technological improvements in almost all structures continuously stretch the limits of acceptance...

Low Cycle Corrosion Fatigue in the North Sea Environment

Low cycle corrosion fatigue is an interesting issue in civil Engineering because it may effect the lifetime of structures in negative and unexpected ways. However, analysis of design codes has revealed that low cycle corrosion fatigue is not a major issue in the design of offshore structures because these structures are designed with a global...