New Experimental Single-Axis Excitation Set-Up for Multi-Axial Random Fatigue Assessments

Fatigue failure, generated by local multi-axial random state stress, frequently occurs in many engineering fields. Therefore, it is customary to perform experimental vibration tests for a structural durability assessment. Over the years, a number of testing methodologies, which differ in terms of th...

Full description

Saved in:
Bibliographic Details
Main Authors: Luca Campello, Vivien Denis, Raffaella Sesana, Cristiana Delprete, Roger Serra
Format: Article
Language:English
Published: MDPI AG 2025-06-01
Series:Machines
Subjects:
Online Access:https://www.mdpi.com/2075-1702/13/7/539
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Fatigue failure, generated by local multi-axial random state stress, frequently occurs in many engineering fields. Therefore, it is customary to perform experimental vibration tests for a structural durability assessment. Over the years, a number of testing methodologies, which differ in terms of the testing machines, specimen geometry, and type of excitation, have been proposed. The aim of this paper is to describe a new testing procedure for random multi-axial fatigue testing. In particular, the paper presents the experimental set-up, the testing procedure, and the data analysis procedure to obtain the multi-axial random fatigue life estimation. The originality of the proposed methodology consists in the experimental set-up, which allows performing multi-axial fatigue tests with different normal-to-shear stress ratios, by choosing the proper frequency range, using a single-axis exciter. The system is composed of a special designed specimen, clamped on a uni-axial shaker. On the specimen tip, a T-shaped mass is placed, which generates a tunable multi-axial stress state. Furthermore, by means of a finite element model, the system dynamic response and the stress on the notched specimen section are estimated. The model is validated through a harmonic acceleration base test. The experimental tests validate the numerical simulations and confirm the presence of bending–torsion coupled loading.
ISSN:2075-1702