Bridges

Cover of Precast Segmental Box Girder Design and Construction within a Constrained Rail Corridor
Precast Segmental Box Girder Design and Construction within a Constrained Rail Corridor
  • Publication no: ABC2017-033-17
  • Published: 20 April 2017

The Level Crossing Removal Project: Caulfield to Dandenong involves the removal of nine of Melbourne’s most congested level crossings along the Caulfield to Dandenong rail corridor. Grade separation of the four level crossings between Caulfield and Hughesdale is achieved by elevating the rail along a 3.1km viaduct which is the longest in Victoria. The viaduct lies within a narrow and heavily constrained corridor in which Melbourne’s busiest rail line operates.

Precast segmental construction is used to minimise the disruption to existing rail services throughout the construction period. The viaduct is erected span-by-span using a specialised straddle carrier and launching system. This is the first project to apply this erection scheme in Australia.

The casting, delivery, assembly and erection engineering is a substantial undertaking with a purpose build casting yard established in Pakenham. The viaduct consists of 87 spans supporting electrified passenger and freight services. Rail infrastructure incorporated in the viaduct includes overhead wiring support gantries, rail signal structures, train stops, direct fixed track and a combined services route. The viaduct supports three elevated stations with island platforms shrouded by an architectural canopy. Geometric constraints and urban design requirements have led to the Up and Down tracks being supported on separate precast segmental box girders.

The design of these compact box girders has necessitated the used of advanced finite element analysis and AASHTO to address the shortfalls of AS5100.