A New Footbridge, Austria

At the site selected for a new footbridge, the banks of the Mur River in Graz, Austria, have an elevation difference of about 2.2 m. The designers felt that a simple straight beam inclined across the river at this point would be aesthetically unsatisfactory. They therefore opted for spanning the river with a beam that was slightly elevated at its centre and horizontally supported by columns, with its upper surface serving as a footpath. The body of the bridge beam has the shape of a composite trilateral prismatoid. In the centre of the bridge, the footpath divides before leading down to the left and right. The aim of the designing a fine-membered bearing structure led to the development of a compound beam construction comprising a stiffening member, with a tensioning member and a compression member on the underside of the bridge.