Experimental investigation of factors influencing external corrosion of buried pipes

Abstract

Corrosion is a serious concern for owners and managers of buried pipelines as it can cause time dependent structural degradation which adversely affects the service life of pipelines. Leaks or rupture caused by corrosion are commonly identified problems in buried metal pipelines which can lead for catastrophic failures causing significant socio-economic losses for consumers as well as water utilities. Despite the periodic inspection of these buried pipelines, the corrosion attack is still one of the major problems in almost every part of the world. Although the corrosion attack can manifest in both internal and external surfaces of pipes, the external corrosion has been reported as the root cause of failure for these pipes. Therefore, an understanding of the external corrosion mechanism and its contributing factors can bring significant insight for corrosion protection of newly installed pipes and maintaining the aged pipes. The current research presents an innovative approach to explore the effects of factors influencing external corrosion of buried metal pipes. The method showed effective outcomes for evaluating the coupled effect of soil pH and moisture on the external corrosion behavior of cast iron pipes buried in natural soil.