Corrosion protection lining

as a type of trenchless rehabilitation technology

consists of installation of flexible high-density polyethylene corrosion protecting liner with V-shaped shear keys inside the existing pipe and filling the gap between the pad and the pipe with cement paste. The corrosion protection lining can effectively improve the flow capacity

corrosion resistance

deformation resistance

and anti-leakage performance of the pipeline and avoid large-scale excavation and replacement of components. To investigate its improving effect on the bending capacity and deformation resistance of ductile iron pipeline

corrosion protection lining was applied to the rehabilitation of the existing DN400 ductile iron water pipeline push-on joints

and a series of pseudo-static tensile and bending test were performed on the push-on joints of the water-pressurized ductile iron pipeline without soil coverage. The mechanical behaviors and failure modes of the push-on joints rehabilitated by the corrosion protection lining were investigated under both axial tensile loading and lateral bending. Failure criteria of the liner-reinforced pipeline joints were established. Comparison of the mechanical properties of the pipeline before and after rehabilitated by corrosion protection lining show that corrosion protection lining can significantly improve the axial tensile and flexural bending capacity of the push-on joint. The experimental results validate and support the application of corrosion protection lining to improving structural behaviors of the burial water pipelines in engineering practice.