MACAULAY ROAD BRIDGE, KENSINGTON, VIC
Macaulay Road Bridge is a 7-span concrete T-beam bridge that was constructed in 1923-24 and is an important link over Moonee Ponds Creek. The piers consist of 5 reinforced concrete columns cast directly into the downstand beams. A structural assessment found that the reinforced concrete beams had inadequate capacity at some locations to comply with current legal vehicle load limits and required strengthening.
Works to repair and strengthen Macaulay Road bridge were tendered by Melbourne City Council in 2006.
In February 2007 Marine & Civil Maintenance was awarded a contract to carry out repairs, strengthening and cathodic protection (CP) to the bridge substructure.
The repair and strengthening works involved the following:
- repair of a total of 4m² of defective concrete by concrete patch repair and crack injection of approximately 260m by epoxy injection;
- design, supply and installation of an impressed current CP system to protect the 30 bridge columns by means of 300 embedded discrete anodes and a water anode system for the submerged parts of the columns;
- design, supply and installation of a impressed current CP system to locally treat areas of deck soffit and beams suffering deterioration from transverse cracking;
- strengthening of the reinforced concrete beams by installation of 260m of bonded steel angles and 240m² of carbon fibre fabric;
- application of protective coatings to all concrete repair areas, the columns and all areas of strengthening.
In order to install the strengthening works it was necessary to implement a traffic management system designed to remove vehicle traffic from each section of the bridge while the strengthening works were being installed.
The contract also included for monitoring of the CP system for 5 years following commissioning, which was
completed in December
2007.