Scanning LDV Measurement Technology for Vibration Fatigue Testing

Experimental Design and Validation of an Accelerated Random Vibration Fatigue Testing Methodology

Shock and Vibration ◽

10.1155/2015/147871 ◽

2015 ◽

Vol 2015 ◽

pp. 1-13 ◽

Cited By ~ 7

Author(s):

Yu Jiang ◽

Gun Jin Yun ◽

Li Zhao ◽

Junyong Tao

Keyword(s):

Fatigue Life ◽

Stress Responses ◽

Life Prediction ◽

Random Vibration ◽

Fatigue Testing ◽

Fatigue Tests ◽

Fatigue Life Prediction ◽

Power Spectral ◽

Vibration Fatigue ◽

Non Gaussian

Novel accelerated random vibration fatigue test methodology and strategy are proposed, which can generate a design of the experimental test plan significantly reducing the test time and the sample size. Based on theoretical analysis and fatigue damage model, several groups of random vibration fatigue tests were designed and conducted with the aim of investigating effects of both Gaussian and non-Gaussian random excitation on the vibration fatigue. First, stress responses at a weak point of a notched specimen structure were measured under different base random excitations. According to the measured stress responses, the structural fatigue lives corresponding to the different vibrational excitations were predicted by using the WAFO simulation technique. Second, a couple of destructive vibration fatigue tests were carried out to validate the accuracy of the WAFO fatigue life prediction method. After applying the proposed experimental and numerical simulation methods, various factors that affect the vibration fatigue life of structures were systematically studied, including root mean squares of acceleration, power spectral density, power spectral bandwidth, and kurtosis. The feasibility of WAFO for non-Gaussian vibration fatigue life prediction and the use of non-Gaussian vibration excitation for accelerated fatigue testing were experimentally verified.

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Measurement and Analysis of the Nonlinear Stiffness of CFRP Components during Vibration Fatigue Testing

Rotating Machinery, Optical Methods & Scanning LDV Methods, Volume 6 - Conference Proceedings of the Society for Experimental Mechanics Series ◽

10.1007/978-3-030-47721-9_7 ◽

2020 ◽

pp. 61-71

Author(s):

Michele Peluzzo ◽

Dario Di Maio ◽

Andrea Cammarano ◽

Paolo Castellini

Keyword(s):

Fatigue Testing ◽

Nonlinear Stiffness ◽

Measurement And Analysis ◽

Vibration Fatigue

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Vibration Fatigue Testing and Analysis

Metal Fatigue Analysis Handbook ◽

10.1016/b978-0-12-385204-5.00009-4 ◽

2012 ◽

pp. 333-382 ◽

Cited By ~ 1

Author(s):

Yung-Li Lee ◽

Hong-Tae Kang

Keyword(s):

Fatigue Testing ◽

Vibration Fatigue

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Harmonic accelerated vibration-fatigue testing

Vibration Fatigue by Spectral Methods ◽

10.1016/b978-0-12-822190-7.00016-5 ◽

2021 ◽

pp. 141-154

Author(s):

Janko Slavič ◽

Matjaž Mršnik ◽

Martin Česnik ◽

Jaka Javh ◽

Miha Boltežar

Keyword(s):

Fatigue Testing ◽

Vibration Fatigue

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Fatigue Testing of Resonating One-way Double-stiffened Plate

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.479-481.2005 ◽

2012 ◽

Vol 479-481 ◽

pp. 2005-2008

Author(s):

Wen Guang Liu ◽

Hong Lin He

Keyword(s):

Natural Frequency ◽

Working Condition ◽

Fatigue Testing ◽

Testing System ◽

Vibration Exciter ◽

Stiffened Plate ◽

Test Pieces ◽

Exciting Frequency ◽

Safety And Reliability ◽

Vibration Fatigue

Problems of vibration fatigue exist in the field of aeronautics and astronautics widespread, which endangered the safety and reliability for structures of aircraft. Vibration-exciter-based fatigue testing system was designed and a method for fatigue testing of the resonating structure was proposed. In test, natural frequency of the test pieces was tracked by the exciting frequency. Experiments are carried out for the typical components with different working condition. One is with given strain, and another is with given force. Results indicate that impacts of the strain amplitude, the damping, the natural frequency and the boundary conditions on vibration fatigue life are obviously.

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Fatigue Strength of Socket Welds Repaired by Structural Weld Overlay: Reference ASME Section XI Code Case N-666

Volume 6: Materials and Fabrication ◽

10.1115/pvp2005-71482 ◽

2005 ◽

Cited By ~ 1

Author(s):

Steve McCracken

Keyword(s):

Residual Stress ◽

Stress Intensity Factor ◽

Finite Element ◽

Fatigue Strength ◽

Fatigue Testing ◽

Element Model ◽

Weld Overlay ◽

Weld Residual Stress ◽

Asme Code ◽

Vibration Fatigue

ASME Code Case N-666 provides alternative rules for repair of a cracked and leaking small bore socket weld by installation of a structural weld overlay [1]. The crack is not removed but is encapsulated and sealed under the weld overlay. Vibration fatigue testing reported by the Electric Power Research Institute (EPRI) demonstrates that socket welds repaired by the method specified in ASME Code Case N-666 have equivalent or better fatigue strength compared to standard socket welds. This paper investigates fatigue test data and fracture mechanics analyses for standard socket welds and compares this to the vibration fatigue strength exhibited by overlay repaired socket welds. A relationship based on fatigue testing of a standard socket weld with root defects was proposed by Japanese researchers to correlate the reduction in fatigue strength with increasing root defect size. This relationship is compared to an EPRI finite element model that was developed to evaluate the stress intensity factor at the root of a standard socket weld. A correction factor is proposed for estimation of the stress intensity factor at the crack tip of a socket weld repaired by weld overlay. The correction factor is derived from a three-dimensional solution for straight pipe with an inside surface circumferential crack and from the finite element model for standard sized socket welds. Finally, weld residual stress analyses reported by Japanese researchers for standard socket welds are compared to weld residual stress data from recent thermal-mechanical finite element analyses for overlay repaired socket welds. The threshold for fatigue crack propagation and the influence of weld residual stress is presented to explain the high vibration fatigue strength exhibited by socket welds repaired by the method of Code Case N-666.

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