West Gate Bridge strengthening

The 2600 m long West Gate Bridge, first opened to traffic in 1978, is one of Australia's most important transport infrastructure assets. It includes an 850 m long cable stayed steel box girder central portion over the Yarra River and segmental prestressed concrete box girder approach viaducts of 670m and 870m long on the western and eastern sides respectively. The West Gate Bridge Strengthening Alliance was formed to undertake all work and improvements relating to a proposed upgrade of the bridge's capacity. In addition, the bridge's performance in relation to carrying existing traffic was to be investigated. This paper presents a summary of the investigation and monitoring work that was conducted in the lead up to the formation of the Alliance and the subsequent detailed assessment work the Alliance has undertaken. An important feature of the assessment is the development of Bridge Specific Assessment Criteria, including specific loading models based on measured data collected using weigh-in-motion equipment installed on the bridge.