Potential of Longitudinal Post-Tensioning for Short-to-Medium Span Timber Bridges

摘要

On the basis of recent developments in post-tensioned multi-storey timber buildings using unbonded tendons, this paper aimed at investigating the potential of implementing a similar technology for innovative solutions for timber bridges. In particular, several technological solutions are proposed for future development, using several different cross sections and longitudinal profiles suitable for short-to-medium bridge spans, with both internal and external longitudinal tendons, in some cases supplemented by transverse post-tensioning. In addition, a feasibility study of a short-span timber bridge is presented, with longitudinally post-tensioned laminated veneer lumber (LVL) hollow core beams as an alternative to the existing concrete solution. The discussion includes a comparison between newly proposed and traditional solutions based on the evaluation of long-term post-tensioning losses, a cost analysis and some considerations on sustainability issues.