Strengthening effects evaluation on fatigue damage of rib to deck joint in orthotropic steel deck

Strengthening fatigue damage of orthotropic steel decks (OSDs) needs to comprehensively consider the strengthening effect and the dead weight introduced during the strengthening process, especially for OSDs in super large-span bridges or old renovated bridges, where the dead weight cannot be significantly increased during repair and...

Probabilistic fatigue analysis on a central holed thick steel plate of C1 Wedge Connection for wind turbine tower assembling

Hole patterns are common in engineering design for connections and/or assembly purposes. Geometrical discontinuities can cause stress concentration in localized areas, making them more prone to fatigue crack initiation and influencing the fatigue life of the overall unit. In the past, much effort has been exerted on fatigue modelling of holed...

Numerical parametric evaluation of ultimate resistance of high-strength bolts

High strength bolts are widely used in the engineering field due to their good compressive properties. Accurate assessment of the ultimate capacity performance of high strength bolts under combined loading is essential to ensure the safety of steel structures in the connection zone. Existing studies are not sufficiently clear on the economic...

Mixed-mode fatigue crack propagation simulation by means of G_eq and walker models of the structural steel S355

In this paper, a numerical simulation method of mixed-mode fatigue crack propagation was explored using the extended finite element method (XFEM) and the Virtual Crack Closure Technique (VCCT). Both 2D and 3D numerical models were selected to simulate the fatigue crack propagation of steel specimens. Two coefficients were proposed to...

Mesh size effects on fracture locus of high strength bolts: A mesoscale critical equivalent plastic strain (MCEPS) approach

With the improvement of computational capability, finite element simulation is an increasingly practical method to accurately predict the ultimate capacity and ductile fracture behavior of high-strength bolts. However, the mesh size affects the results of FE simulations but related research on mesh size effects is relatively limited. In the...

Fatigue crack growth modelling for S355 structural steel considering plasticity-induced crack-closure by means of UniGrow model

The UniGrow model is an analytical procedure to assess the fatigue crack growth based on elastic–plastic crack tip stresses and strains. The assumption is that fatigue crack growth (FCG) can be considered as a process of successive crack re-initiations resulting from material damage in the crack tip zone. The main parameters of this model are...

Fatigue reliability of wind turbines: historical perspectives, recent developments and future prospects

Wind, as a sustainable and affordable energy source, represents a strong alternative to traditional energy sources. However, wind power is only one of the options, together with other renewable energy sources. Consequently, the core concerns for wind turbine manufacturers and operators are to increase its reliability and decrease costs,...

Fatigue experimental characterization of preloaded injection bolts in a metallic bridge strengthening scenario

All over the world, the number of civil engineering structures, particularly bridges with long service periods, has been increasing. The most common evidences of damages are the presence of corroded metallic elements and cracks in structural details due to the fatigue phenomenon. A large number of cases were found in which fatigue cracks were...

Residual stress effects on fatigue life prediction using hardness measurements for butt-welded joints made of high strength steels

The fatigue resistance of welded connections made of high strength steel (HSS) is one of the most important topics for the application of HSS in the construction sector. One of the most challenging issues is how to predict the fatigue life of welded structures with complex geometry based on the test results from relatively simple coupon...

Ductile fracture locus identification using mesoscale critical equivalent plastic strain

The ductile performance of high strength steel (HSS) from different steel grades, producers, manufacturing processes varies a lot. It is also difficult to conduct all kinds of reliable experiments to generate different stress status through different initial specimen geometries or by applying different load combinations in the civil...

Fracture parameters calibration and validation for the high strength steel based on the mesoscale failure index

Accurately obtaining the material parameters of the damage model is very important for the ductile fracture simulation of steel structures made of high strength steel (HSS). The combination of micromechanics with the uncoupled phenomenological fracture model can be used to obtain the material parameters of ductile fracture locus only from the...

Three-dimensional fatigue crack propagation simulation using extended finite element methods for steel grades S355 and S690 considering mean stress effects

The assessment of fatigue crack propagation of steel structures is essential and important especially to improve the application of high strength steel in construction. The load ratio R, reflecting mean stress effects, will be changed with crack extension in the steel structures with complicated geometry. In this paper, the Walker equation is...

Probabilistic strain-fatigue life performance based on stochastic analysis of structural and WAAM-stainless steels

Wire arc additive manufacturing (WAAM) has increasingly attracted attention in the construction sector because of its ability to produce large metallic structural parts in short times. In this paper, Coffin-Manson and Morrow (CMM) equation is employed to compare the fatigue life of WAAM stainless steel with the structural steels S355 and S690...

Reliability of Fatigue Strength Curves for Riveted Connections Using Normal and Weibull Distribution Functions

In North America and Europe, there is a significant number of centenary metallic bridges that require maintenance and strengthening operations. These structures need to be adapted to increasing traffic intensities, and their structural integrity should be constantly evaluated. Fatigue damages were not considered in the original design of old...

Fatigue resistance curves for single and double shear riveted joints from old portuguese metallic bridges

The maintenance and safety of ancient bridges is a major concern of governmental authorities. In particular, the safety of old riveted bridges fabricated and placed into service at the end of the 19th century deserves particular attention. These structures are susceptible to exhibit high fatigue damage levels due to their long operational...

Alternative steel lattice structures for wind energy converters

Purpose: In the last decades, the demand and use of renewable energies have been increasing. The increase in renewable energies, particularly wind energy, leads to the development and innovation of powerful wind energy converters as well as increased production requirements. Hence, a higher supporting structure is required to achieve higher wind...

Global Fatigue Life Modelling of Steel Half-pipes Bolted Connections

A steel hybrid structural solution for onshore wind turbine towers was proposed in the European project SHOWTIME. This solution is used in the lattice structure for the lower portion of the tower. Recently, a procedure for fatigue life estimation of steel half-pipes bolted connections applied in global structural models using multiaxial Smith...