Mechanical response of the pressure pipeline rehabilitated by polymer liner under the action of surface load

The mechanical behavior of pressure pipelines rehabilitated with polymer liners under surface loads remains poorly understood. In this study, a three-dimensional model of a pressure pipeline repaired with a polymer liner is developed and validated against existing results. The effects of various factors—such as position, burial depth, load offset distance, host pipe (pressure pipe) diameter, surface load, host pipe thickness, liner thickness, liner elastic modulus, internal pressure, and the friction factor between the host pipe and liner—on the axial strain and displacement distribution of the pressure pipeline are analyzed. The findings reveal that the load’s influence on the pipeline is confined to within 5 meters of the load center. As the offset distance increases, the strain and vertical displacement at the pipe crown decrease, while the lateral displacement at the pipe crown initially increases before decreasing. Additionally, the lateral displacement at the pipe springline reverses direction. This study offers valuable insights for the operation and maintenance of pressure pipelines.