Concrete block mattress revetment alternative for the Roy Hill Infrastructure Rail loop

BGC Contracting has successfully constructed approximately four kilometres of coastal revetment using a bespoke flexible concrete block mattress system on the Roy Hill Iron Ore Port Landside Rail-loop, Port Hedland, Western Australia. The adopted precast concrete blocks system was developed as an alternative to the originally approved, traditional rock armour revetment, and offered the possibility of both time and cost savings to the project. This paper explores how BGC Contracting, in conjunction with their sister company BGC Precast and head contractor Samsung C and T, managed to design, test, manufacture, and install 45,000 m2 of revetment between April 2014 and March 2015. The completed design process is broadly discussed, including the challenges represented by the adoption of a precast concrete mattress revetment, and the verification of its suitability by means of physical model testing. Additional discussion regarding fabrication and installation challenges, and some of the subsequent innovative solutions, is also provided. The paper is concluded with a summary of the benefits realised from the alternative revetment design.