Strengthening Timber Roof Trusses during Building Construction and Reconstruction

摘要

The relevance of this article is explained by the increasingly extensive efforts associated with construction and reconstruction of buildings and structures having mainly architectural and cultural significance, as well as preserving their pristine ambience and integrity for use by future generations. Furthermore, reconstruction helps to serve a range of social demands, such as the provision of comfortable and safe living conditions for people. The review of research publications shows that wooden structures are the first to lose their load-bearing capacity during the long-term use of buildings and structures. Still, the scientific literature mostly features the traditional labor-intensive methods of timberwork strengthening that further increase its weight, or the methods of external reinforcing with composite tapes. This article, for the first time, discusses the technology of the strengthening timber framing with butterfly-shaped wooden inserts. Joints between existing rafters and wooden inserts are reinforced with two layers of the furniture duct tape and fine composite mesh pressed in between, with the plywood top finishing of the duct tape. The experimental studies that were in progress for two years showed that the technology suggested meeting all the reliability requirements applicable for timber trusses. As compared to traditional technologies, the suggested solution is less labor-intensive and more sparing in terms of the truss weight, as it only adds the weight of furniture duct tape, composite mesh and plywood at the joints. This is the applied research, and its outcome can be used not only for strengthening of roof timber, but also for reinforcing of wooden inter-floor joists.