Stay-cable Bridge Construction Accelerated

The standard cast-in-place segmental balanced-cantilever construction technique for long-span, cable-stayed bridges has been well known and widely used; however, it can lead to extensive construction time and places the construction of the pylon on the critical path of the schedule. The Oakley C. Collins Memorial Bridge over the Ohio River (between Ironton, Ohio and Russell, Kentucky, USA) was built with a new construction technique targeting this issue and accelerating construction by implementing several innovative value engineering ideas proposed by COWI, the Contractor’s Construction Engineer. These include the use of back-span falsework, allowing the side span superstructure to be cast-in-place on falsework during pylon construction; the use of precast stay anchor blocks for rapid installation and better geometry control of the stay anchorages; and guide pipes and unidirectional cantilever casting, reducing the casting cycle duration to as little as one segment per week. This paper presents the construction details that significantly reduced the superstructure casting schedule and design modifications to the superstructure.