Fatigue debonding resistance of wrapped composite X-joints

Steel jacket support structures for offshore wind turbine towers made of circular hollow sections (CHS) are becoming a competitive solution compared to monopiles in deeper waters. The current limitation to improving the durability and cost-effectiveness of the CHS structures is the low fatigue endurance of their welded joints. Fatigue-driven...

Fatigue crack growth characterization of composite-to-steel bonded interface using ENF and 4ENF tests

In this paper, mode II fatigue crack growth properties of the composite-to-steel interface are characterised through different test configurations, namely ENF and 4ENF tests. Different loading types including force control and displacement control methods are compared. An innovative shear strain based method is proposed for monitoring the...

焊接残余应力对钢桥面疲劳性能的影响与处理措施

In order to improve the fatigue resistance of orthotropic steel decks (OSDs), the steel bridge deck was annealed to reduce the welding residual stress of key welds. This work at first presented a systematical review and discussion over the distribution pattern of welding residual stress in OSDs, in accordance with a conceptual analysis...

Influence of surface roughness on the mode II fracture toughness and fatigue resistance of bonded composite-to-steel joints

Hybrid bi-material concepts in engineering structures where fibre-polymer composites are used together with steel structural members have potential to reduce material usage, extend fatigue life and improve structural reliability. The bond performance of the bi-material composite-to-steel interface is of crucial importance and highly relies on...

Interfacial fatigue debonding retardation in wrapped composite joints: Experimental and numerical study

Debonding crack propagation at the composite-to-steel interface has been found to be an important failure mechanism for wrapped composite joints under static and fatigue loads. Friction at the interface behind the crack tip may deviate fatigue debonding of the joints from the linear-fracture-mechanics behaviour. This paper presents static and...

Combined DIC and FEA method for analysing debonding crack propagation in fatigue experiments on wrapped composite joints

Wrapped composite joint is a novel joining technology which connects steel hollow sections through bonding, completely avoiding the welding in the load transferring mechanism. Fatigue performance of wrapped joints has been experimentally shown to be superior over their welded counterparts. Aiming to enable development of prediction methods...

Machine Learning-Assisted probabilistic fatigue evaluation of Rib-to-Deck joints in orthotropic steel decks

This study integrates the fatigue test and numerical prediction to derive a comprehensive probability-stress-life (P-S-N) curve for rib-to-deck (RD) welded joints in orthotropic steel decks. Fatigue tests of RD joints are conducted to measure fatigue strength and crack growth data. Based on the test, a probabilistic fatigue crack growth (PFCG...

A two-dimensional ordinary state-based peridynamic model for surface fatigue crack propagation in railheads

Based on ordinary state-based peridynamic theory, a 2D peridynamic model has been established to investigate fatigue crack propagation in railheads. The proposed model is verified in terms of rail deformation under a quasi-static load and the ductile material-related fatigue failure model. Good agreements have been achieved between a finite...

Fatigue behaviour of non-welded wrapped composite joints for steel hollow sections in axial load experiments

Design and execution of fatigue load dominated circular hollow section (CHS) multi-membered structures, such as offshore jacket and floating structures for wind turbines, truss bridges, etc., is hinged on fatigue performance of critical welded joints. An innovative jointing technology of wrapped composite joint connects steel hollow sections by...

Fatigue evaluation on headed stud connectors with toe-plate failure mode using hot spot stress approach

The headed stud connectors are widely used in a variety of innovative engineering applications of the infrastructure sector. The fatigue life of headed studs is significantly affected by the residual stress introduced from welding procedures. It is very important to develop a reliable numerical method to predict the fatigue performance of...