Steel profiles for repairing deteriorated timber beam ends

Authors

  • C. González-Bravo Universidad Antonio de Nebrija
  • F. Arriaga Universidad Politécnica de Madrid
  • G. Íñiguez-González Universidad Politécnica de Madrid
  • L. Maldonado Universidad Politécnica de Madrid

DOI:

https://doi.org/10.3989/ic.10.004

Keywords:

timber, steel, finite elements method, upgrading, rehabilitation

Abstract


This paper describes the design of a procedure for the upgrading of timber floor joists with decayed ends using steel profiles connected to timber from the upper side of the flooring. The reinforcement consists on a steel S275 U cold formed shape with a plate inserted into timber and connected by means of screwing into the wood. For the experimental verification 30 beams were tested in bending obtaining the stiffness and load carrying capacity. The specimens were divided into three groups. The first was composed by 10 pieces of glued laminated timber of Spruce with 180 x 200 mm cross section; the second one was composed by 10 pieces of sawn timber of Scots pine with the same cross section; and the third one was constituted by 10 solid timber beams of genus Pine with 130 x 150 mm cross section, from a 120 years old building in Madrid. Each group of 10 pieces was divided in two groups of 5 beams. The first sub-group was constituted by the beams with the whole length as a reference group. The pieces of the second one had a shorter length that was substituted by the steel extension. It can be concluded that the steel profile reinforcement can solve the problems derivates from the unsafe support caused by wooden decay affecting a certain and limited length (approximately from 10 to 20% of the length).

Downloads

Download data is not yet available.

References

(1) F. Arriaga; F. Peraza; M. Esteban; I. Bobadilla; F. García: Intervención en estructuras de madera. p. 476., Editorial AITIM, Madrid, 2002.

(2) Landa, M.: “Nuevas técnicas de reparación de estructuras de madera. Elementos flexionados. Aporte de madera-Unión encolada I. Metodología de puesta en obra”. Revista de Edificación nº 28, Pamplona (1999), pp. 32-38.

(3) Landa, M.: “Nuevas técnicas de reparación de estructuras de madera. Elementos flexionados. Aporte de madera-Unión encolada II. Metodología de puesta en obra”. Revista de Edificación nº 29, Pamplona (1999), pp. 30-36.

(4) Anon: “The age of resin”. The Architects Journal, Feb. (1982) pp. 56-58.

(5) Mettem, C. J.; Page, A. V.; Robinson, G. C.: “Repair of structural timbers. Part I: Test on experimental beam repairs”. TRADA, Technical Report. Reino Unido (1993).

(6) González-Bravo, C.: “Recuperación de la capacidad mecánica en piezas de madera solicitadas a flexión en estructuras tradicionales operando por la cara superior mediante refuerzos y prótesis metálicas”. Tesis Doctoral. Universidad Politécnica de Madrid, ETS de Arquitectura. 265 p. (2007) PDF file: http://oa.upm.es/442.

(7) González-Bravo, C.; Arriaga, F.; Díez, R.: “Bending reinforcement of wooden beams with steel cross sections”. Proceedings of the 10th World Conference on Timber Engineering. Miyazaki, Japan (2008).

(8) González-Bravo, C.; Arriaga, F.; Maldonado, L.; Díez, R.: “Refuerzo de vigas de madera mediante perfiles metálicos situados en la cara superior”. Mater.Construcc. Vol. 60, nº 298 (2010) pp. 123-135. doi:10.3989/mc.2010.47408

(9) UNE-EN 10025-1:2006. Productos laminados en caliente de aceros para estructuras. Parte 1: Condiciones técnicas generales de suministro. (Hot rolled products of structural steels - Part 1: General technical delivery conditions).

(10) DIN 571 Tirafondos para madera con cabeza hexagonal (Hexagon head wood screws).

(11) UNE-EN 408:2004. Estructuras de madera. Madera aserrada y madera laminada encolada para uso estructural. Determinación de algunas propiedades físicas y mecánicas. (Timber structures. Sawn timber and glued laminated timber for structural use. Determination of some physical and mechanical properties).

(12) EN 13183-2:2002. Contenido de humedad de una pieza de madera aserrada. Parte 2: Estimación mediante el método de la resistencia eléctrica. (Moisture content of a piece of sawn timber. Part 2: Estimation by electrical resistance method).

(13) Documento Básico de Seguridad Estructural, Acero. Código Técnico de la Edificación. Ministerio de la Vivienda. (BOE 23/102007 y 25/01/2008).

(14) UNE-EN 1993-1-1:2008. Eurocódigo 3: Proyecto de estructuras de acero. Parte 1-1: Reglas generales y reglas para edificios.

Downloads

Published

2011-03-31

How to Cite

González-Bravo, C., Arriaga, F., Íñiguez-González, G., & Maldonado, L. (2011). Steel profiles for repairing deteriorated timber beam ends. Informes De La Construcción, 63(521), 37–45. https://doi.org/10.3989/ic.10.004

Issue

Section

Research Articles