Fatigue Failure of Large-Diameter Cast Iron Mains

Water utility engineers have reported on large diameter water main failures that occurred suddenly without warning, no signs of prior leaks and no visual evidence of corrosion on the fracture surfaces. Often these failed mains had been operating without major problems for over 80 years. A possible explanation may be attributed to alternating or fluctuating stresses such as those caused by heavy traffic and cyclical operating water pressure with...