Fatigue behaviour of self-piercing riveted joints

2010 ◽

Author(s):

Michele Ferracci ◽

Francesco Vivio ◽

Vincenzo Vullo

Keyword(s):

Degrees Of Freedom ◽

Complex Structure ◽

Element Model ◽

3D Models ◽

Fatigue Behaviour ◽

Fe Analysis ◽

Structural Behaviour ◽

Fe Modelling ◽

Closed Form Solutions ◽

Riveted Joints

A theoretical approach, in order to define the structural behaviour of riveted joints, is presented. The closed form solutions lead to the definition of a Rivet Element useful to FE models of multi-riveted structures. The objective is an accurate evaluation of the local stiffness of riveted joints in FE analysis, which is fundamental to perform a reliable simulation of multi-joint structures and, consequently, a good estimate of loads acting on connections; this makes it possible to introduce new general criteria allowing, for example, to predict fatigue behaviour. On the other hand, a low number of degrees of freedom is needed when several connections are present in a complex structure. The goal is to reach a reliable model of the rivet region which can be used as the basis to develop a Rivet Element in FE analysis. The proposed Rivet Element combines the precision in the simulation with a very limited number degrees of freedom in the finite element model of a complex structure having several rivets. In the present paper the structural behavior of two simple riveted specimens is investigated experimentally and numerically using a new Rivet Element. A comparison with a joint model performed with very refined non-linear 3D models of rivet and with experimental data is performed and a good agreement is shown.

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Experimental Validation of Riveting Process Fe Simulation

Fatigue of Aircraft Structures ◽

10.2478/fas-2018-0006 ◽

2018 ◽

Vol 2018 (10) ◽

pp. 63-72

Author(s):

Wojciech Wronicz

Keyword(s):

Material Model ◽

Fatigue Behaviour ◽

Point Of View ◽

Stress System ◽

Critical Areas ◽

Fe Simulations ◽

Riveted Joints ◽

The Press ◽

Riveting Process ◽

Force Displacement

Abstract Rivets are critical areas in metal airframes from the fatigue point of view. Fatigue behaviour of riveted joints depends strongly on the residual stress system around the rivet holes. The both most convenient and most common method of determining these stresses is the Finite Element (FE) analyses. The validation of models used is necessary to ensure the reliability of results. This paper presents the validation process of the riveting FE simulations for the universal and the countersunk rivets. At first, the material model of the rivets was validated with the use of the force–displacement curves of the press stamp obtained experimentally. Because of the displacement measurement method, it was necessary to take into account the flexibility of the stand. After that, good correlation between the numerical simulations and the experiment was obtained for both rivet types. At the second stage, strains around driven heads measured with the use of strip gauge patterns were compared with the results of the FE simulations. Quite good correlation was obtained for the countersunk rivet. In the case of the universal rivet, the numerical results are significantly higher values than the measured ones. Differences in correlation of the experiments and FE simulations for the analysed rivet types probably result from material differences of the rivets.

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Contribution to the study of the influence of the stress ratio on the high cycle fatigue behaviour of riveted joints

Fatigue & Fracture of Engineering Materials & Structures ◽

10.1111/ffe.13324 ◽

2020 ◽

Vol 43 (12) ◽

pp. 3027-3036

Author(s):

Stéphane Sire ◽

Paul Dario Toasa Caiza ◽

Bernard Espion ◽

Muriel Ragueneau

Keyword(s):

Stress Ratio ◽

High Cycle Fatigue ◽

Fatigue Behaviour ◽

Cycle Fatigue ◽

Riveted Joints

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Applicability of Empirical Formulae for the Fatigue Notch Factor to Estimate Riveted Lap Joint Fatigue Strength

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.224.81 ◽

2014 ◽

Vol 224 ◽

pp. 81-86

Author(s):

Tomasz Machniewicz ◽

Małgorzata Skorupa ◽

Andrzej Skorupa ◽

Adam Korbel

Keyword(s):

Fatigue Life ◽

Load Transfer ◽

Fatigue Behaviour ◽

Fatigue Tests ◽

Lap Joints ◽

Riveted Joints ◽

Riveted Joint ◽

Fatigue Notch Factor ◽

Riveted Lap Joints ◽

Semi Empirical

A semi-empirical fatigue life prediction model under development by the present authors for riveted lap joints used in aircraft structures is outlined. In contrast to existing models, it will account for the influence of the rivet squeeze force on the fatigue life of riveted joints. To determine the effect of rivet-hole interference on the fatigue behaviour of a riveted joint, a series of fatigue tests on filled hole coupons with different amounts of interference will be carried out under loading conditions representing the bypass load, transfer load and secondary bending. These experiments will allow evaluating of the dependency of the fatigue notch factors on rivet hole expansion. Preliminary results obtained so far are presented in this paper.

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