Repetitive Loading Effects on Cast Iron Pipelines with Cast-in-Place Pipe Lining Systems

Abstract

This paper focuses on the response of circumferentially cracked cast iron (CI) pipeline with the cast-in-place pipe (CIPP) lining system by evaluating stresses, relative displacements, and rotations generated by repetitive loadings, including the thermal expansion and contraction effects, actual traffic loading, backfill effects, and adjacent excavations. Detailed analytical models were developed to relate axial and vertical displacements and rotational distortions imposed on pipeline at the circumferential crack. The analytical results were used to establish laboratory test procedures to simulate repetitive loadings. Laboratory tests were performed on CIPP lined CI pipes in accordance with the analytical model. By concentrating on cracked sections of CI pipe, the mechanical aging tests provide quantitative means of characterizing the liner performance under the most severe conditions that would be anticipated during general operations.