As part of the ongoing flood damage repair program being undertaken by the Department of Transport and Main Roads, AllenCon was contracted alongside ProBuild to deliver PICR Package 9 throughout the Sunshine Coast Hinterland stretching to Esk, in the Brisbane Valley.
PICR Package 9 consisted of six projects in total and AllenCon delivered four of these packages:
Site 1 – Road Slip Remediation
Site 8A – New Batter Excavation and Road Realignment
Site 8B New Batter Excavation, Fill to Gully & Road Realignment
Existing conditions on the road included localised shoulder closures and a one-lane/one-direction lane closure was necessary to undertake the works on Site 8B. This closure was regulated by temporary traffic lights.
Stage 1 of the road slip remediation works required the controlled filling of a significant embankment slip. The excavation was carried out by 20T excavator, with material haulage by body trucks. The fill works required the installation of temporary sheet piles, with over 250m2 of sheet piling completed on the site, and was undertaken in a two-stage process including the provision of a grout filled layer
Over 3,700m3 of special rockfill was placed throughout the project and the construction of a new pavement/carriageway on top of this completed Stage 1.
Stage 2 works saw the switch of traffic onto the newly constructed carriageway and the construction of the remainder of the new road. The works were delivered using typical pavement widening equipment, 20T excavator (box-out/embankment) 6T single drum roller, single axle water-truck and posi-track.
The remainder of the temporary side-track was removed during this stage with the one-lane/one-direction traffic scheme remaining in operation and regulated by temporary traffic lights.
Slip Remediation/Slope Stabilisation & AC Rebuild
Site ch6.44 – Bored Piles/Capping Beam/Backfill & Pavement
Site ch8.52 – Slip Remediation & Gabions/Backfill
Site ch4.05 – Slope Stabilisation/Rock Anchors & Pavement
This project was carried out under lane closure (southbound carriageway) that resulted in one-lane/one-direction traffic. The traffic flow was regulated by the installation of temporary traffic lights, operating 24/7.
The works included the installation of over 400 soil nails to an excavated face at 60 degrees. Excavation of the site required the use of long reach excavators and a small Marini rig from the lower benches where larger rigs could not access.
The location of the site, atop a very steep ridge, required a strong safety focus to ensure the wellbeing of personnel on site. The use of specialised rope access was arranged to enable the operation of multiple drilling rigs and shotcreting crews.
In order to reach the client’s programme, two crews were run consecutively, to complete the works and have the road open to two lanes of traffic by 20th December.
Works were completed under PICR Conditions of Contract as part of the Natural Disaster Relief and Recovery Arrangements (NDRRA).