South Pine River and Tributary Creek Bridge Upgrades
Contract Value: $12M
Design and construct project consisted of the upgrade of the existing rail bridge structures at South Pine River and Tributary Creek on the North Coast Line. These structures carry the Middle Road and Up Main. The project works consists of the removal and demolition of existing super structures, demolition of original concrete substructure, erection of the new prestressed concrete decks, replacement of ballast, track and OHLE to suit the new structures. Works also included re-construction of 120m of embankment between the 2 bridges and the approaches at either end. All permanent works were completed during a seven day rail track closure from 24th to 30th December 2015.
Time lapse footage of the demolition and reconstruction of the bridges during the closure period can be viewed here.
The design, undertaken by GHD, was to upgrade the two bridges measuring approximately 110m and 330m long, to meet Queensland Rails 300A loading criteria. A realignment, which included raising the track level and increasing the curve radius, was also incorporated into the works to allow for speed increase to 100km/hr.
Temporary works for the project required approximately 400m of crane pads, consisting of ecoflex tyres and clean rock, topped with a running layer of gravel. Other works included a 36m section of falsework bridge into South Pine River to support a 250t crawler crane and access equipment.
JF Hull utilised the services of specialist contractors, Rosenlund for the demolition, Martinus Rail for the track work and Laing O’Rourke for the OHLE.
The project required 6 months of design, procurement, planning and preparation works for almost all of the permanent works to be completed in the 7 day closure period between Christmas and New Year.
Key features of this project include:
- Demolition: Demolition included removal of 39 spans of superstructure consisting of 4 steel girders per span, cross bracing and timber transoms. These were removed in whole span sections with 4 large crawler cranes. 12 large (30-70t) excavators were used for the substructure demolition, consisting of a total of 36 concrete piers to 600mm below ground level and 2 steel piers in the river to 600mm below bed level.
- Earthworks: The underlying material in the embankment and approaches was saturated, very low strength clay. Removal and replace treatment up to 1m deep was required incorporating the use of geogrid, wrapped rock layers and gravel capping layers.
- Superstructure Installation: Installation of 1248 bearing pads, 156 QR deck slabs, 16 precast transition slabs, 8 sets of precast stairs, all within the allotted 48 hour time period during the 7 day SCAS closure. Additionally, there was approximately 900m of prefabricated bridge walkway installed on deck planks prior to the closure. The installation of the superstructure works required 4 crews with 4 large (150-250t) crawler cranes working non-stop on rotating shifts.
- Track Work: Remove and replace 1509m of ballast, sleepers and rail on both the middle road and up main, including guardrail for the full length of the works. Ballast was installed using a combination of moxie trucks and direct placement with a mobile conveyor, as well as the use of the ballast train.
- OHLE: Removal of existing and installation of new masts and overheads for the length of the project for two rail lines.
- All works during the Christmas closure were completed within the allotted time frame and with no delays to the rail network
- Fatigue and high pressure were concerns for such an immense amount of work in a short period of time. Extensive safety planning for the SCAS works meant the completion of the 7 day work period with minimal injury and incident
- The project team worked closely with QR’s communications team to keep the community informed in the lead up to, and during the holiday closure. No complaints were reported, despite 7 days of continual loud work over the holiday period
- Site located in a river and flood plain, no environmental issues were encountered. The ecoflex system, with clean rock was used for crane pads to minimise sediment and all demolished materials stored in bunded hardstand areas
This project was awarded the 2015 National CCF Earth Awards Category 4 for excellence in civil construction, the 2015 Queensland CCF Earth Awards Category 4 for excellence in civil construction and the X-Tra Mile Award from Permanent Way Institute.