Remediation of Culverts Beneath Roadways

Abstract

Mainmark received a 2021 Good Design Award in the Engineering category for the repair, rehabilitation and future-proof of culverts beneath the Toowoomba Bypass. The capability to efficiently repair culverts with minimal disruption to the road users above provides amenity to local communities and a cost-effective alternative to replacement for Councils. Mainmark will present three projects that demonstrate the benefits of in-situ culvert repair rather than replacement. A two cell 2100 Roundel culvert near Atherton required rectification works after a significant rain event caused degradation of the fill material about the culvert. Chemical compaction grouting was used to compact and strengthen the fill about the pipes to ensure the long-term durability and performance of the structure. A three cell RCP culvert in an ACT state park suffered piping through the embankment following a flood event. GPR investigation identified extensive voiding about the pipes, placing the road over and the stone pitch end walls at risk. The voids about the pipe were filled and the throughflow stopped in a single day, minimising the impact of lengthy road closures on park users. At Toowoomba bypass seven RCP culvert structures required remediation due to compromised barrels. Mainmark provided a grouted liner solution to restore the integrity of the structures. Each project was successfully completed on time and within budget. Key Words: Culvert, Remediation, Repair, Teretek™