PSI - Issue 51

Zhihua Xiong et al. / Procedia Structural Integrity 51 (2023) 179–184 Z. Xiong et al. / Structural Integrity Procedia 00 (2022) 000–000

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The dimensions of the CL-shaped dowel remain the same as those described in section 2, the difference is that the concrete foundations are made of a different material. In the absence of cracks, the stress in the CL-shaped dowel is shown in Fig. 9(a). Half of the elliptical cracks were set at the stress concentration and the crack propagation using the XFEM method is shown in Fig. 9(b).

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Fig. 9. (a) stress distribution of dowels in pull-out specimens; (b) path of crack propagation of dowels.

Similarly, the pattern of I-type stress intensity factor exhibited with crack length ‘a’ for CL-shaped dowel containing cracks was discussed in the pull-out test and the results are shown in Fig. 10.

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1000 stress intensity factor ( MPa*mm ½ ) 1500 2000

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Fig. 10. Result of pull-out tests-SIF vs crack length.

5. Conclusions and outlook In order to investigate the fracture of CL-shaped dowels, bending-shear and pull-out models were analyzed by extended finite element method. After extensive numerical simulations, the results show that crack propagation can be captured by setting cracking-related coefficients. The T beam model shows different crack initiation locations and cracking paths. The obtained stress intensity factors according to the cracking paths are in an expected range and can be used as a reference. Before further calibration by experimental data, this is a qualitative investigation. References Berthellemy, J., 2013. Fatigue designed CL-cutting shape: A new economic steel-concrete connection system and some applications for bridges. Procedia Engineering 66, 138-149. Berthellemy, J., Hechler, O., Lorenc, W., Seidl, G., Viefhues, E., 2009. Premiers résultats du projet de recherche européen Precobeam de connexion par découpe d'une tôle. Construction métallique 46, 3-26. Feldmann, M., Kopp, M., Pak, D., 2016. Composite dowels as shear connectors for composite beams–background to the German technical approval. Steel Construction 9, 80-88.