- Published:
Estimation of stiffness and strength in timber knee joints with adhesive and verification by experiment
Journal of Wood Science volume 52, pages 411–421 (2006)
Abstract
The use of adhesive joints is gradually increasing, especially those with glued-in steel rods (GIRs). There are, however, some problems with the design methods when used for moment-transmitting applications. In this article, design methods for GIRs and cross-lapped glued joints (CLJs) are proposed. For CLJs, we made a hypothesis that both rotational deformation of CLJ and stress of the glue line occurred with bending and shearing deformation of the timber. Using this hypothesis and Kelvin’s theorem, a mechanical model of CLJ is proposed. For GIRs, the axial stress component of the rod and the lateral stress component of the rod were taken into account using the theory of a beam on an elastic foundation. From the comparisons between calculations and experimental results, it was recognized that the stiffness and strength of CLJs and GIRs could be predicted precisely using our proposed models.
References
Komatsu K (1985) Strength design of cross-lapped glued joints for glulam portal frames (II): an approach to designing the strength of glued joints proving tensional stress is proportional to the distance from the rotation center. J Hokkaido For Prod Res Inst 402(1):1–9
Komatsu K (1985) Strength design of cross-lapped glued joints for glulam portal frames (I): an approach to designing the strength of glued joints proving glue lines suffer stress equivalent to those in a parallelogram bar subject to a pure tensional moment. J Hokkaido For Prod Res Inst 402(6):1–9
Komatsu K (1978) Strength of the joints with glued splint plates subjected to edgewise pure bending (in Japanese). Mokuzai Gakkaishi 49:19–86
Komatsu K (1984) Application of fracture mechanics to the strength of cross-lapped glued joints. FRI Bulletin 61, New Zealand Forest Service, New Zealand
Komatsu K, Koizumi A, Sasaki T, Jensen J, Iijima Y (1997) Flexural behaviour of GLT beams end-jointed by glued-in hardwood dowels. In: Proceedings of CIB W18-Timber Structures, Vancouver, CIB-W18/30-7-1
Timoshenko S, Goodier JN (1951) Torsion. In: Theory of elasticity. Kogakusha, Tokyo, pp 258–263
Kelvin WT, Tait PG (1912) Treatise on natural philosophy, vol 2. Cambridge University Press, pp 267-268
Komatsu K (1995) Moment resisting joint (in Japanese). In: Structural design note for timber structures. Maruzen, Tokyo, pp 184–221
Aicher S, Gustafsson PJ, Wolf M (2000) In: Proceedings of 1st RILEM Symposium on Timber Engineering, Stockholm, Sweden, pp 369-378
CEN/TC250/SC5 N158 (2001) Annex A: connections with glued-in steel rods. In: prEN 1995-1-1 Eurocode 5. CEN, Brussels, pp 105-108
Blass H, Görlacher R, Laskewitz B (2002) GIROD — glued in rods for timber structures. In: SMT4-CT97-2199, SP report, pp 34-43
Noguchi M, Komatsu K (2004) Design method of the knees-joints using adhesive for the wooden portal frame structures. In: Proceedings of the WCTE, Lahich, vol 3, pp 301–304
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Noguchi, M., Komatsu, K. Estimation of stiffness and strength in timber knee joints with adhesive and verification by experiment. J Wood Sci 52, 411–421 (2006). https://doi.org/10.1007/s10086-005-0802-z
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s10086-005-0802-z