Winchelsea masonry arch bridge, Australia: first major maintenance

The existing three-span stone arch bridge across the Barwon River at Winchelsea in Australia was opened on 3 December 1867 by HRH the Duke of Edinburgh, Prince Alfred. For 145 years, this now heritage-listed bridge has carried traffic on the Princes Highway West without loading restrictions. An inspection in 2012 revealed significant cracking of the voussoirs and a load rating of 23 t was posted. The Princes Highway West upgrade project will provide a new river crossing so that the stone arch bridge will revert to carrying pedestrians and cyclists. However, during the construction of the new bridge, the existing stone arch bridge is required to be reopened to traffic without a posted load limit to carry one lane of traffic for up to 2 years. An engineering investigation was therefore required to determine what rehabilitation works were required to facilitate this. This paper presents the results of an engineering investigation to determine a reliable way of replacing the cementitious material between the voussoirs of the bridge. The experience obtained during re-grouting of the three stone arches, which was successfully completed in January 2014, is also discussed.