Structural performance of corroded concrete pipes after mortar spraying rehabilitation under traffic load

Abstract

At present, the insufficient structural performance of pipelines leads to frequent road collapse accidents. More and more urban areas have adopted trenchless repair techniques to improve the structural performance of existing corroded pipelines and prolong their service life. The spray method has been widely used due to its advantages of convenient construction, environmental protection, and substantial flexibility, but it lacks a theoretical basis. This paper established a three-dimensional numerical model for concrete drainage pipelines with bell and spigot joints by Abaqus numerical analysis software based on a full-scale test, aiming to verify the feasibility of the spray repair technology and provide a theoretical basis for this method. The impact on the mechanical properties of the pipelines under different traffic loads was analyzed by comparing the establishment of an intact pipe, a corroded pipe, and a repaired pipe. The results show that the traffic load significantly impacts the section of the pipeline adjacent to its acting position. Furthermore, the higher the traffic load is, the more prominent of the influence on the vertical displacement of the pipe joint became. Stress concentration occurs in the corrosion area of the corroded pipeline subjected to the traffic load. The spray repair method could help reduce the stress concentration and improve the structural performance of the pipeline. The pipeline repair efficiency could reach to 13.45%–53.25% under various conditions. The findings of this work can provide theoretical support for the spray repair design of corroded drainage pipelines.