Fatigue Crack Paths 2003

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C P Syst m W elde Bead

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(b) Fatigue crack pr pagation lives

(a) Crack paths

Estimation by CP system xperime t(Bottom Side) T p Side) Run Out Cycle ofExperi ent

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Figure 7. Experimental and predicted results for Model2 specimen.

C O N C L U S I O N S

It has been found by the present case study that there exists a possibility of the fatigue

design, which optimizes structural details in such a way that fatigue cracks could be

detectable and non-hazardous even though they may initiate. It is confirmed that the

present simulation method is very useful for the prediction of fatigue crack paths and

the crack propagation lives, so that it can be applied to the fatigue design and remaining

life assessment of an actual structural detail of a welded structure.

A C K N O W L E D G E M E N T S

This work has been supported by the Program for Promoting Fundamental Transport

Technology Research (Project No.2001-03) from Corporation for Advanced Transport

and Technology (CATT), and by the fund from Japan Ship Classification Society (Class

NK). The authors are grateful for their support.

R E F E R E N C E S

1. Yagi, J., Machida, S., Tomita, Y., Matoba, M. and Soya, I. (1991) Journal of the

Society of Naval Architects of Japan 169, 289- 299 (in Japanese).

2. Sumi, Y. (2003) Computational crack path prediction for ship structure details.

Proceedings of the Conference on Fatigue Crack Paths (FCP2003).