Počet záznamů: 1

Lifetime prediction of HDPE pipes grade

  1. 1.
    0354108 - UFM-A 2011 RIV DE eng C - Konferenční příspěvek (zahraniční konf.)
    Nezbedová, E. - Hutař, Pavel - Ševčík, Martin - Náhlík, Luboš - Knésl, Zdeněk
    Lifetime prediction of HDPE pipes grade.
    European Conference on Fracture. Vol. 18. Berlin: Deutscher Verband fur Materialforschung und prufung e.V, 2010 - (Klingbeil, D.; Vormwald, M.; Eulitz, G.), s. 1-9. ISBN 978-3-00-031802-3.
    [18th European Conference on Fracture. Dresden (DE), 30.08.2010-03.09.2010]
    Grant CEP: GA ČR GA106/08/1409; GA ČR GC101/09/J027; GA ČR GA106/09/0279
    Výzkumný záměr: CEZ:AV0Z20410507
    Klíčová slova: HDPE * creep crack * time to rupture curve * PENT test * pipe failure
    Kód oboru RIV: JL - Únava materiálu a lomová mechanika

    This paper presents the results of notch tests on single edge notch specimen under condition corresponding to the PENT approach, i.e. at temperature 80°C and nominal stress 2,4 MPa. Tests were performed for one monomodal and two bimodal HDPE materials, both from structural and fracture mechanics point of view. The dependence of a crack opening displacement COD vs. time was measured and the values of the rate of the stable crack growth rate da/dt and time to fracture tf were estimated. To estimate the residual life of pipes the finite element model with an initial defect was suggested and the values of the stress intensity factor K have been calculated. The computation took into account the change of the crack shape during its growth in the pipe. For assessment of the residual service life of pipes the relation da/dt = A (K)m was applied. The values of the pipe life-time for three studied materials are compared and diagram of the hoop stress versus failure time is presented.
    Trvalý link: http://hdl.handle.net/11104/0193185