PSI - Issue 42

Dennis Domladovac et al. / Procedia Structural Integrity 42 (2022) 382–389 Domladovac et al. / Structural Integrity Procedia 00 (2019) 000–000

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• The localisation of a 40 mm gap in the adhesive layer of a DCB specimen loaded in mode I is possible with all used measurement methods, but the size of the gap cannot be measured exactly. • It must be mentioned that the results of the deflection curve approach are sensitive to the numerical di ff erentia tion, the resulting rise of numerical noise and the choice of filters. Especially by the three times di ff erentiation of the DIC method. The BFSM is slightly robuster, but for the traction also two times di ff erentiation is needed. • With the BFSM method, the determination of the J-Integral is possible as well and the values agree with the ones calculated according to Paris and Paris. The J-Integral evaluation shows that the material properties of the adhesive in this case of load and with a gap can not be characterized, only the joint behaviour. • Inclinometers are a useful and simple tool to check whether the process zone reaches the specimen end and also to measure a integration constant for the deflection curve approach.

Acknowledgements

The work has been partially funded by the Hessian Ministry of Higher Education, Research, Science and the Arts (HMWK), Germany, within the internal program “Strategischer Forschungsfonds” of TH Mittelhessen. The financial support is gratefully acknowledged. Furthermore, the authors would like to thank Sabine Wenig (SIKA Automotive AG, Romanshorn, Switzerland) for supplying the adhesive.

References

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