Slow Crack Growth
Plastic Pipes Conference Association # 2004 Milan
Jeffrey, Moser, Folkman
A research project sponsored by Uni-Bell PVC Pipe Association dealing with the fatigue strength of PVC (polyvinyl chloride) pipe was recently completed at Utah State University. The objective of the project was to develop an improved methodology for predicting fatigue failure of 6-inch (152 mm) PVC pipes. The tests completed during this effort focused on fatigue failure at lower stress amplitudes. The test results show that the design criteria based on work by previous researchers are very conservative, particularly if the stress amplitude is small. New curves for predicting fatigue failure are presented. The results are very applicable for engineers designing municipal water and pressurized sewer systems.
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