Case Study: Void Filling of Annulus For Stormwater Pipe Culvert

Our Solution:

Resinject proposed injecting Resin from inside the stormwater pipe via a pattern of small, upward direction drill holes through the new liner, which would be backfilled and sealed post-injection.

Due to the length of the pipe, Resinject proposed accessing the stormwater pipe via three points: one at each end of the culvert and one near the middle of the culvert. This positioning would be the most optimum for Resinject to achieve the nominated productivity and ensure the entire length of the pipe annulus void was sufficiently filled with Resin.

The Resin used for this void filling would not only provide a watertight and flexible membrane around the new fibreglass liner but would also save considerable time in the construction program since it was estimated to only require a total of five days to complete.

Wilmot accepted Resinject’s proposal, and the treatment was scheduled in for immediately after the liner was installed. Resinject’s treatment included a pattern of over 600 injection holes drilled at 1.2m spacings throughout the top half of the pipe liner. The injected Resin migrated around the full circle of the annulus and the remnant drill holes were backfilled with flexible sealant. The void filling works were successfully completed within four days which also enabled Wilmot to save another day in their construction program.

Wilmot were delighted with the results and the efficiency of the service delivery. Furthermore, avoiding the use of cementitious grout in this instance saved on labour time and environmental impact with the considerable clean-up usually required after void filling works.

Resinject-Case-Study_Wilmot-Relined-Pipe-Annulus-Filling-3.pdf