Fluid migration into lined pipelines

Lining of a pipe with a polymeric liner is a viable trenchless technology for rehabilitating sewer pipelines. Polymeric liners are typically installed within the deteriorated segments of a sewer line, from one access hole to the next, to essentially create a new pipe within the old pipe without the need for excavation and removal. However, some concerns exist regarding the need to grout or seal the joints where the new liner connects with access holes and laterals. The purpose of this study is to provide some insight into the degree of fluid migration into, or from, the system at these connecting points under simulated field conditions. Four groups of three similar vitrified clay pipelines were lined with different types of deformed-reformed or fold-and-form (DR/FF) liners and cured-in-place-pipe (CIPP) liners then tested to assess the conditions of the annular space between the liners and the host pipe. Fluid migration was detected around all liners and flow rates in the annular space increased with the head difference between the upstream and downstream ends of the test pipelines. No significant changes were observed in the flow rates within the annular space in the tested pipelines over the eight-week testing period.