Double Cable System Suspension Bridge, Indonesia

The new bridge over the Mamberamo River in Irian Jaya, Indonesia, is part of a road development project in an agricultural area. Since roadworks were incomplete at the time of construction, transport of materials to the bridge site was a particular challenge in this project. The river at the crossing site has a rapid flow and the river bed is quite rocky. Rather than attempt to construct river piers in such circumstances, it was decided to span the crossing with a single span, 235 m suspension bridge. At this span length, the towers could be set back some 10 m from the river banks. The towers are prefabricated steel frames with site-bolted connections. The main cables are in dual asymmetric arrangement for optimum stiffness. Total weight of cable was about 120 t. The timber deck consists of transverse deck planks with timber kerbs to delineate the carriageway.