On the Prediction of Long-Term Creep-Failure of GRP Pipes in Aqueous Environment

• Type: Article in International Scientific Journal
• Date: 2010

Authors

Rui Miranda Guedes (Author) FEUP; Alcides Sa (Author) Other; Hugo Faria (Author) Other

Journal

Title: Polymer Composites

Vol. 31 No. 6

Pages: 1047-1055

ISSN: 0272-8397

Publisher: Wiley-Blackwell

Indexing

ISI Web of Knowledge - 11 Citations

ISI Web of Science

Scopus - 16 Citations

COMPENDEX

Scientific classification

FOS: Engineering and technology > Materials engineering

Other information

Authenticus ID: P-003-6GJ

DOI: 10.1002/pc.20891

Abstract (EN): The aim of this work was to study the long-term failure of GAP (Glass fiber-reinforced Polymer) pipes under the influence of moisture absorption. These pipes are used in water transportation, which has an important effect on the mechanical properties of the polymeric matrix. The GRP pipes are usually tested under ring deflection or internal pressure conditions. This study presents and analyzes experimental creep-rupture data obtained from standard test methods under ring deflection conditions. This loading configuration simulates in laboratory the conditions verified in a subsoil installation. The creep testing was carried out under constant dead weight on unconditioned and preconditioned samples in a submerged condition. The diametrical deflection of samples was measured periodically, and the time to failure of each sample was recorded. The main purpose of this work was to determine the short and long-term rupture energies of GRP pipes and assess the influence of moisture preconditioning on those values. The observed failure mode was always the same. It was concluded that the energy at failure decreases with time. The influence of the preconditioning on the creep-rupture of GAP pipes was considered negligible. Different time-dependent failure models were described and used for long-term extrapolation of the experimental data. The maximum strain at failure decreased about 12% from 0.1 to 1,000 hr of creep testing. Furthermore, data extrapolation to 50 years predicts a reduction of strength of about 60%, founded on the most conservative time-dependent failure criterion. POLYM. COMPOS., 31:1047-1055, 2010. (C) 2009 Society of Plastics Engineers

Language: English

Type (Professor's evaluation): Scientific

Notes: DOI: 10.1002/pc.20891

No. of pages: 9