Epping to Thornleigh: Third Tracking (ETTT) - Bridge
While working at BECA, CSS team members were responsible for the Detailed Design of the new rail bridge over Devlin’s Creek and the M2 (alternative continuous Super-Tee girder bridge comprising 2 X 37.5m continuous spans plus 24.35 and 37.5m continuous spans), permanent retaining walls for the support of the southern embankment (including a platform for the construction of the bridge southern abutment) comprising piled foundations, cast-in-situ blade walls with Reinforced Soil Walls over. Temporary Works Design included the construction of a temporary access road for the construction of the southern embankment retaining wall and the construction of a temporary crane pad and access roadway to the north of Devlin’s Creek for the construction of the bridge pier 2 and for the erection of the bridge girders to spans 1, 2 & 3.
As the Project Director and Structures Lead for this project, Vince was responsible for the delivery of the load rating assessment review of the superstructure and led the load rating assessment of the substructure. Vince Scolaro, Mehran Ameli and Brendan Quinn were also responsible for the checking of the final design rectification works for the superstructure, detailed design of the new piers, the design checking of the existing superstructure for all temporary works required and the drawing delivery for the bridge substructure and all temporary works. This included assessment of the existing bridge superstructure for the proposed hanging scaffold, identification of all bridge superstructure reinforcement to ensure minimal existing reinforcement was damaged for the installation of all bearing plates and external tensioning anchors, assessment of the existing piers for the temporary bracing required to ensure alignment of the new piers with the bridge bearings under thermal variations and responsible for all CPS activities. The proposed strengthening design involved the addition of external pre-stress to both the main span and back spans, addition of 2 new piers (one under each half joint, replacement of the bearings to include a soft (elastomeric bearing) and hard (pot bearing) at each new pier, provision of new shear keys at each new pier and remediation of the existing concrete barriers.
Technical innovations achieved
Development of a temporary bracing / stressing system for the jacking of the existing bridge and construction of the new bridge bearings and shear keys under live traffic.
Benefits to the Client
Traffic restrictions virtually eliminated (with the exception of the bridge jacking process).
