Pinter, Haager, Balika, Lang
# 2004 Milan
In this work fatigue crack growth (FCG) experiments were used to evaluate the long term performance of polyethylene (PE) pipe grades. The FCG-tests were performed under a sinusoidal load at a frequency of 5 Hz, an R-ratio (Fmin/Fmax) of 0.1 and a test temperature of 23 °C. Eight different commercial pipe grades (PE 80 and PE 100) were included into the investigations. A procedure could be established to initiate quasi-brittle cracks that led to failure within 60 hours. Crack growth initiation times were determined from crack opening displacement data and crack growth kinetics were analysed using linear elastic fracture mechanics (LEFM). For the investigated materials the ranking by FCG was in reasonable agreement with results from Full Notch Creep Tests (FNCT).
