Evaluation of HDPE Pipelines Structural Performance
Structural performances of 191 HDPE pipelines throughout 10 different states throughout the nation were investigated. The sites were selected to cover diverse geographical locations. Qualitative and quantitative observations and measurements were performed using a pipeline inspection camera and a pipeline laser profiling unit. Several failure modes were identified for all the pipelines tested including: cracking/fracture, excessive deformation, joint displacement, inverse curvature and buckling. This study showed that 100% of the pipelines tested suffered from some or many of the aforementioned failure modes. In 68% of the pipes tested, the governing maximum deformations (Y, X, and/or ovality) of 5% was exceeded. A maximum value of 34% was observed for the maximum deformation and the average of maximum deformations was 7.6% among all pipelines inspected. This study indicates that structural health and integrity of the installed HDPE pipelines tested are generally below structurally acceptable levels of serviceability.
