CONCRETE CABLE-STAYED BRIDGES

This paper presents a comprehensive review on a case-study basis of concrete cable-stay bridges either completed, under construction or in design, with the intent of encouraging designers to consider the feasibility of this type of structure. Evolution of concrete cable-stay bridges is traced from Torroja's Tempul Aqueduct in Spain, completed in 1925, to present day design concepts. Particular attention is given to structure concept, geometric configuration, design considerations, structural details, and method of construction. As late as 1970, the practical span limit of steel cable-stay bridges was considered to be 300 m (1,000 ft). Recently, concrete cable-stayed bridges are considered technically feasible with spans approaching 500 m (1,600 ft). It has been projected that with an aerodynamically shaped composite concrete and steel deck a span of 700 m (2,300 ft) can be achieved. With today's technology of prefabrication, prestressing, and segmental cantilever construction, it is obvious that cable-stay bridges are extending the competitive span range of concrete construction to dimensions that had previously been considered impossible. The technological means exist, they only require implementation. /Author/