Precast Prestressed Segmental Elevated Urban Motorway in Italy

Abstract

The design and construction of an elevated urban motorway that was built in the city of Bolzano, Italy, using precast prestressed concrete segmental construction is described. The viaduct consists of 74 spans giving an overall length of 2580 m (1.6 miles). The superstructure is made up of one post-tensioned concrete multi-cell box-section spine beam with cantilever side slabs. The basic construction method of the superstructure is the span-by-span mode using percast segmental units erected on falsework and post-tensioned together. Each of the 34.5-m (113.2 ft) spans is composed of nine segments 2.20 m (72.8 ft) wide by 1.6 m (5.2 ft) deep and weighing 110 tons. The precast elements are connected by a thin layer of epoxy resin adhesive. In the wintertime, the surface to be bonded was electrically heated. The average erection time cycle for the superstructure was one span per week. The viaduct was completed in April of 1974. /Author/