Tarban Creek Bridge
Bridge Length: 230m
Bridge Width: 28m
Construction Dates: 1965
Length of main span: 90m
Approach spans: 8 x 17m
The Tarban Creek Bridge was completed in 1964 and opened to the public in 1965. Prior to this opening, the crossing of the river was to the west and required traffic to navigate through the streets of Hunters Hill to the displeasure of residents. With the completion of Tarban Creek Bridge the link between the Gladesville Bridge and Fig Tree Bridge was complete allowing a more direct route north.
The overall bridge length of 230 metres includes a main central span of 90 metres and eight approach spans of approximately 17 metres each. The deck width of 28 metres includes six traffic lanes, a median and one footway. The concrete structure forming the main span comprises five parallel arch ribs, three metres wide and spaced at 5.8 metre centres. Each rib consists of a main beam supported by two inclined portal legs. The main beam forms the crown of the arch and is also cantilevered over each portal leg. The main beam and portal legs were constructed from tapered precast box segments.
A system of post-tensioned tendons joins all the segments of each rib together. The ribs are connected transversely by reinforced concrete diaphragms between the main beams above the portal legs and at the cantilevered ends. Post tensioning and prestressing are efficient methods for reinforcing concrete using high strength steel strands typically referred to as tendons, which are tensioned to enable the structure to carry greater loads with minimal cracking and deflections.
The Tarban Creek Bridge was built as part of the never completed North Western Freeway with the intention to link the CBD with the suburbs of the northwest and F3/M1 to Newcastle. After a number of arrests and political threats, the project was suspended and ultimately cancelled in 1977.