PSI - Issue 25

Available online at www.sciencedirect.com Available online at www.sciencedirect.com ScienceDirect Structural Integrity Procedia 00 (2019) 000–000

www.elsevier.com/locate/procedia

ScienceDirect

Procedia Structural Integrity 25 (2020) 430–437

© 2020 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/) Peer-review under responsibility of the VCSI1 organizers Abstract Our aim is to assess HDPE pipes’ degradation through the failure and reliability modelling by referring only to static tests and models instead of tedious and very costly dynamic ones. For that reason, we were interested in two kinds of specimens, standard ones for tensile test characterization and pipe ones for burst test purpose. The study was conducted over old and newly produced pipes specimens with multilevel notches. Indeed, the specimens were prepared according to the ASTM D 638 and ASTM 1599 respectively. Thus, we were able to establish four concepts of damage models based on the stress, the strain and the energy parameters, to quantify the ageing degradation effect on old pipes, and the burst pressure one, for the notched pipes. Therefore, the obtained results were compared considering neat, old and notched specimens for both the two tests. Then, we showed that the damage is somewhat symmetric around the critical life fraction of 52%. Besides, we concluded that the maintenance of the pipes become obligatory when we get over this point. In addition, the cross-discussion of damage-reliability curves allowed us to assess the limits of the HDPE pipes’ mechanical behavior. Thus, the irregularity of the damage through the wall of the old pipes allowed us to quantify and predict the consumed lifetime of them. These proposed simplified approaches have the advantage to assess quickly the degradation and stability of the studied polymer and decide the right maintence policy regarding the damage-reliability behavior of the studied specimens. © 2020 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/) h 1st Virtual Conference on Structural Integrity - VCSI1 Maintainability and reliability of high density polyethylene pipes through experimental and theoretical models Fatima Majid a,d, *, Rajaa Rhanim b , Mohammed Lahlou e ,Hassan Rhanim a , Mohammed Ezzahi c , Mohamed Elghorba d a Laboratory of Nuclear, Atomic, Molecular, Mechanical and Energetic Physics, University Chouaib Doukkali, El jadida, Morocco. e ENSAJ, LabSIPE, University chouaib Doukkali, EL Jadida, Morocco . b Laboratory Study of Advanced Materials and Application, University Moulay Smail, Meknes, Morocco. c Laboratoire Energie et Systèmes Electriques (LESE), ENSEM, Université Hassan II, Casablanca, Morocco. d Laboratoire de contrôle et de caractérisation des matériaux et des structures, Université Hassan II, ENSEM, Casablanca, Morocco.

* Corresponding author. Tel.: +212 663 49 90 78; E-mail address: majidfatima9@gmail.com

2452-3216 © 2020 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/) Peer-review under responsibility of the VCSI1 organizers

2452-3216 © 2020 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/) Peer-review under responsibility of the VCSI1 organizers 10.1016/j.prostr.2020.04.048