Bridges

Melbourne's Level Crossing Removal Project (LXRP) is being delivered across a number of alliances. LXRP had requested that the various alliances standardise the designs where possible to provide a benefit to the supply chain for these works. A standardised concrete U-trough elevated bridge girder was developed by the alliances capable of carrying rail traffic to meet this request.

A U-trough girder was developed as two prestressed concrete girders that could be stitched together at the soffit to complete the U shape of the span prior to erecting. These girders were developed for several standard span lengths, for each alliance, with standardised concrete outlines, reinforcing details and strand patterns.

This paper focusses on the design of the 27m U-Trough girders and how the concrete web design was assessed to perform under out of plane bending and longitudinal shear from a train derailment loading. The paper will look at how the unique stress distribution in the web under this scenario exceed the design applicability of AS5100 and how Eurocode EN 1992-2's 'Sandwich Method' and first principles were used to assess the design.