Notch stress and fracture mechanics based assessment of fatigue of seam weld ends under shear loading

Shams, Ehsan; Malikoutsakis, Michail; Savaidis, Georgios; Vormwald, Michael

doi:10.1111/ffe.12186

Cited by 21 publications

(14 citation statements)

References 37 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…The modelling steps of such an idealised weld end geometry are comprehensively described in [1][2][3][4][5][6]. A submodelling technique has been used, in order to calculate the von Mises equivalent stresses.…”

Section: Notch Stressesmentioning

confidence: 99%

“…Normally, fatigue design of welded components proceeds from S-N curves (fatigue strength versus number of cycles). Concerning weld start and end points, the knowledge of S-N curve parameters is limited to either normal [1][2][3][4][5] or shear [6] stressed structures. In these investigations, dealing only with uniaxial loading conditions, geometrically idealised weld end models with concept radii of r normal = 0.20 mm respectively r shear = 0.05 mm were created.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Sharp three-dimensional notches under combined nominal normal and shear fatigue loading

Vormwald¹,

Shams²

2017

Frattura Ed Integrità Strutturale

Self Cite

View full text Add to dashboard Cite

ABSTRACT. Many engineering structures are exposed to non-proportional fatigue loading. However, at the critical location of crack initiation, often only one of the load sequences dominates -the individual load cases result in different crack initiation sites. Based on engineering judgment a simplified local uniaxial or proportional loading situation may be assessed. In general, the critical location must be identified by calculating fatigue lives for a variety of locations. The position of the critical location depends on the hypothesis applied for life calculation -besides loading, geometry, material and many other influence factors. For sharp three-dimensional notches the region for the search of the critical location may be restricted considerably. Weld start and stop points are an industrial example for such sharp notches. They are the object of the present investigation. They are exposed to nominal normal and shear loading. The individual hot spots for crack initiation lie necessarily close together. A strong interaction of the loading cases for both proportional and non-proportional loading was experimentally observed. In the numerical investigation notch stresses were calculated using an idealised weld end model. Based on the critical plane approach according to Findley, numerical interaction lines were produced.

show abstract

Section: Notch Stressesmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Sharp three-dimensional notches under combined nominal normal and shear fatigue loading

Vormwald¹,

Shams²

2017

Frattura Ed Integrità Strutturale

Self Cite

View full text Add to dashboard Cite

show abstract

“…Im numerischen Arbeitspaket wurden Kerbspannungen für die Einheitslastfälle Normalkraft und Torsionsmoment basierend auf einem idealisierten Nahtendmodell mittels der Finite‐Elemente‐Methode (FEM) berechnet. Nähere Informationen zum Nahtendmodell können der Literatur entnommen werden . Die Geometrie des Nahtendes weist einen Nahtwurzelradius von 0,05 mm und einen Nahtübergangsradius von 0,2 mm auf.…”

Section: Numerische Analysenunclassified

“…Heute liegen Konzepte zur Schwingfestigkeitsbewertung von Nahtenden in zug‐ und schubbeanspruchten Nahtenden vor . Hierbei wurden idealisierte FE‐Nahtendmodelle für beide Lastfälle entwickelt.…”

Section: Introductionunclassified

Schwingfestigkeitsbewertung von Nahtenden unter kombinierter Beanspruchung

Shams

Vormwald

2016

Materialwissenschaft Werkst

Self Cite

View full text Add to dashboard Cite

In dieser Arbeit wird eine Methode zur Berechnung der Schwingfestigkeit von Nahtenden in Feinblechstrukturen unter kombinierter Normal‐ und Schubbeanspruchung basierend auf Kerbspannungen vorgestellt. Die Berechnung der Kerbspannungen erfolgte mit Hilfe der Methode der Finiten Elemente unter Zuhilfenahme der Submodelltechnik. Ein idealisiertes Nahtendmodell wurde verwendet, um die Beanspruchungssituation für solche Lastsituationen zu bewerten. Zudem wurde unter Einsatz eines Berechnungsverfahrens Größeneinflüsse zweier Arten, zum einen der spannungsmechanische und zum anderen der statistische Größeneinfluss, berücksichtigt. In Verbindung mit Bruchschwingspielzahlen aus Schwingversuchen wurde eine konzeptgebundene Kerbspannungswöhlerlinie ermittelt. Somit liegt erstmalig eine Bewertungsmethode nach dem Kerbspannungskonzept für die Schwingfestigkeit von Nahtenden unter kombinierter Beanspruchung vor.

show abstract

“…Methods for calculating the fatigue life of notched components can be divided into local and non-local. [19][20][21][22][23] The non-local methods take into account the influence of the stress gradient and define a zone which is considered as equivalent and in which significant fatigue processes take place. The first is global, where calculations are performed based on nominal stress, external forces and fatigue notch factor K f .…”

Section: Introductionmentioning

confidence: 99%

Non‐local line method for notched elements with use of effective length calculated in an elasto‐plastic condition

Krzyżak

Robak

Łagoda

2016

Fatigue Fract Eng Mat Struct

View full text Add to dashboard Cite

The paper presents a non‐local line method used to the fatigue life calculation of notched elements. The presented method is based on the concept of an effective length which determines the size of the equivalent fatigue zone. Effective values of normal stress calculated in the critical plane with a weight function were applied when determining the equivalent fatigue zone. Simulation studies were performed for two types of steel and two types of loading. Five different series of tests and simulations were used. Experimental studies were carried out for 40 HM‐T and EA4T steels. These materials are used in railway industry, including the manufacturing of coupling bars. The notched test specimens contained notches with a tip radius of 0.2, 0.5, 0.8 and 1 mm. Stress calculations were performed using the finite element method by adopting cyclic material properties described by the model of a multi‐linear hardening. Non‐local calculations were performed in a defined critical plane for normal stress distribution and a weight function. As a result, the function of variation of the effective length depending on the loading level and geometry of the notch has been determined.

show abstract

Notch stress and fracture mechanics based assessment of fatigue of seam weld ends under shear loading

Cited by 21 publications

References 37 publications

Sharp three-dimensional notches under combined nominal normal and shear fatigue loading

Sharp three-dimensional notches under combined nominal normal and shear fatigue loading

Schwingfestigkeitsbewertung von Nahtenden unter kombinierter Beanspruchung

Non‐local line method for notched elements with use of effective length calculated in an elasto‐plastic condition

Contact Info

Product

Resources

About