Reinforcement of Timber Beams with Prestressed Wires

Abstract:

This paper presents and discusses the possibility of improving the bending strength of timber beams through the use of prestress. The emphasis is put on various methods of imposing the prestress force and transferring it into the wood part: i) through post-tension, with the force being mechanically anchored on the ends of the wood elements; ii) through pre-tension, with the anchorages being either mechanical, as in the previous system, or glued, with the force being gradually transferred through shear stresses along a certain length of the wire/wood interface. Although the risk of failure due to tension perpendicular to the grain in the anchorage regions exists, it is not specifically studied in here, due to the limited scope of the study. The main conclusion is that any of the procedures may be advantageously used with either small (mass-production) or large-span glued-laminated timber beams and, though they are mostly suited to the production of new elements, they may also be adapted to the strengthening of existing beams.

• Periodical: Advanced Materials Research (Volume 778)
• Pages: 596-603
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.778.596
• Online since: September 2013
• Authors: João Henrique Jorge de Oliveira Negrão
• Keywords: Anchorage, Epoxy, Post-Tension, Pre-Stress, Pre-Tension, Timber

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