Underground oil and gas pipelines are usually expected to be long-lasting. Corrosion of these steel pipelines may cause structural failures that significantly threaten life and cause environmental hazards. Therefore, developing a reliable approach to estimate soil corrosivity is important for designing a targeted anti-corrosion structure and performing risk assessment. In this study, an extension-based approach is proposed to evaluate soil corrosivity based on the following seven soil properties: redox potential, soil resistivity, pH, pipe-to-soil potential, water content, Chloride (Cl⁻) concentration, and salt content. Specifically, the soil was classified into five corrosivity levels, and the classic domain element, joint domain element, and element to be evaluated were established by the matter-element theory. Then, the corrosivity level was determined based on the maximum correlation degree of the multi-index to the five levels, and the final classification was obtained from the eigenvalues of the grade variables. Finally, the case study was examined to validate the application of the approach, and the results were compared to the method of buried metal specimens, which was used as a criterion. The present approach, which provided a more detailed classification, was demonstrated to be a superior choice for classifying soil corrosivity levels.

地下石油和天然气管道通常预计会很持久。这些钢质管道的腐蚀可能会导致结构故障，从而严重威胁生命并造成环境危害。因此，开发一种可靠的方法来评估土壤腐蚀性对于设计目标抗腐蚀结构和进行风险评估非常重要。在这项研究中，延伸为基础的方法，提出了评估基于以下七个土壤性质土壤腐蚀性：氧化还原电位，土壤电阻率，pH值，管地电位，水分，氯离子（CL ^-）浓度和含盐量。具体而言，将土壤分为五个腐蚀性等级，并通过物元理论建立了经典的域元素，联合域元素和要评估的元素。然后，根据多指标与五个等级的最大相关程度确定腐蚀性等级，并从等级变量的特征值获得最终分类。最后，对案例研究进行了验证，以验证该方法的应用，并将结果与​​埋入式金属标本的方法进行了比较，该方法被用作标准。提供了更详细的分类的本方法被证明是对土壤腐蚀性水平进行分类的最佳选择。