An Evaluation of the Effective Block Approach for Predicting Crack Growth under an Untested Spectrum Using P-3C and F-111 Test Data

Chris Wallbrink; Wei Ping Hu

doi:10.4028/www.scientific.net/AMR.41-42.189

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A Practical Approach for Evaluation of Thermal Shock SIF's in Flexibly Restrained Edge-Cracked Plates
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Discontinuous Growth Mechanisms of Mode II Crack under High-Speed Impact Conditions
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Diagnosing Boiler Tube Failures Related to Overheating
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The Frequency Effects on Fatigue Threshold of PVC-M and PVC-U in Air and Water Medium
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An Evaluation of the Effective Block Approach for Predicting Crack Growth under an Untested Spectrum Using P-3C and F-111 Test Data
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Deterioration Mechanisms in Dragline Wire Ropes
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Fracture of Quasi-Brittle Materials like Concrete under Compressive Loading
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Adhesion Property of Copper Paste on Ceramic Radiator Fins
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Does Size Matter? - The Effect of Volume on the Compressive Strength of Open Cell Brittle Ceramics
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HomeAdvanced Materials ResearchAdvanced Materials Research Vols. 41-42An Evaluation of the Effective Block Approach for...

An Evaluation of the Effective Block Approach for Predicting Crack Growth under an Untested Spectrum Using P-3C and F-111 Test Data

Abstract:

Recently an effective block approach has been proposed to address the experimentally observed high growth rates of fatigue cracks at the critical locations on F/A-18 airframes. This approach treats a spectrum block as one equivalent constant amplitude cycle. Hence, the crack growth rate may be represented by a Paris-type equation, with the model parameters dependent on the load spectrum. This approach has been applied to the F/A-18 crack growth analysis, with good correlation to experimental data. In this paper, we summarise recent evaluation work of the approach using experimental data obtained under P-3C and F-111 spectra. An improved method for transferring the model parameters from a tested spectrum to an untested spectrum, suggested by the first author of the current paper, has been evaluated in comparison to the original procedure proposed. The soundness of relying on third-party tools based on constant amplitude model for the prediction of relative severity of spectra is also discussed. Finally, the advantages and limitations of the effective block approach are highlighted.