Abstract Corrosion induced degradation of fracture toughness in buried cast iron pipes is a serious concern for structural integrity and smooth operation of buried pipes. External corrosion of pipes is fundamentally governed by the corrosivity of soil which may vary depending on the type of soil and its specific properties. While the corrosion assessments of pipes buried in soil can provide realistic behaviour, the investigations of pipe corrosion in simulated soil solutions are becoming popular due to simplicity. Limited studies are reported in the literature using simulated soil solution for determining the effect of corrosion on the fracture toughness of cast iron specimens. However, it is important to evaluate the outcomes based on the solutions benchmarking against the corrosion from the realistic soil environment. This study investigates the corrosion of cast iron specimens in both the acidic soils and the simulated soil solutions of the same varying pH for 365 days. The fracture toughness testing of the corroded specimens taken out from both the real and simulated soil solutions was performed at 180 and 365 days, respectively. The fracture toughness (KQ) values of the corroded specimens of the two soil mediums were compared and correlated statistically. Moreover, relations for the variation in KQ of specimens as a function of corrosion rates, and pH with time were developed for soil and simulated soil solution. The findings of this research have practical applications for the predictions of the service life of buried cast iron pipes.

中文翻译：

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腐蚀介质导致铸铁断裂韧性下降

摘要 埋地铸铁管中腐蚀引起的断裂韧性退化是影响埋地管道结构完整性和平稳运行的一个严重问题。管道的外部腐蚀从根本上取决于土壤的腐蚀性，这可能会因土壤类型及其具体性质而异。虽然埋在土壤中的管道的腐蚀评估可以提供真实的行为，但由于简单，模拟土壤溶液中的管道腐蚀调查正变得流行。使用模拟土壤溶液来确定腐蚀对铸铁试样断裂韧性的影响的文献中报道了有限的研究。然而，重要的是根据针对现实土壤环境腐蚀的解决方案来评估结果。本研究调查了铸铁试样在酸性土壤和具有相同不同 pH 值的模拟土壤溶液中 365 天的腐蚀情况。从真实和模拟土壤溶液中取出的腐蚀试样的断裂韧性测试分别在 180 天和 365 天进行。比较两种土壤介质腐蚀试样的断裂韧度（KQ）值并进行统计相关。此外，研究了土壤和模拟土壤溶液中试样 KQ 随腐蚀速率和 pH 值随时间变化的关系。这项研究的结果对预测埋地铸铁管的使用寿命具有实际应用价值。