Reliability Index of HDPE Pipe Based on Fracture Toughness

Type : Publication
Auteur(s) :  L. Alimi, S. Azzouz, K. Chaoui, A. AMIRAT
Année :  2017
Domaine : Génie mécanique
Revue : MECHANIKA
Résumé en PDF :  (résumé en pdf)
Fulltext en PDF :  (.pdf)
Mots clés :  HDPE pipe, critical stress intensity factor, crack length, SDR, reliability index, PHIMECA software

Résumé : 

his work presents a contribution to evaluate the reliability of a high density polyethylene (HDPE) pipe using the PHIMECA Software. The critical stress intensity factor (KIC) is adopted as a criterion to the maximum limit of a numerically calculated KI. The reliability index β is obtained using failure probability and a mechanical model. It is found that at lower KIC, no safe domain for actual service pressures existed while for moderate and higher values of KIC (above 3.5 MPa.√m); the β design index is reached and even exceeded. In terms of increasing crack length, β decreased systematically for all toughness cases supporting the idea that reliability and fracture toughness designate similar properties for service life or material resistance to cracking. For a KIC=5 MPa.√m, the pipe is considered safe when crack length is below 370μm. Finally, it is shown that SDR basis is a reasonable and conservative design approach for plastic pipes.