Fig. 1 The principal axes of wood
Fig. 2 Wood specimens
Fig. 4 Humidity in outer and inner chambers at the target humidity of 80%
Fig. 6 Evolution of strain with respect to the moisture content
Fig. 5 Weight during the drying test
Fig. 7 Strains at various temperatures along the three directions
Fig. 8 3-point bending test of wood specimens
Fig. 9 Warped wood specimen and the amount of warping
Fig. 10 Amounts of warping at various humidity conditions
Fig. 11 Finite element model
Fig. 12 Predicted equilibrium moisture content
Fig. 13 Annual zones and local orientations of the wood specimen
Fig. 14 Moisture content distribution of the deformed wood specimen at the humidity of 75, 85, and 95 % after 11 days
Fig. 3 Setup of the humidity chamber
Table 1 Hygroscopic expansion coefficients
Table 2 Thermal expansion coefficients
Table 3 Conditions for 3-point bending test
Table 4 Orthotropic elastic constants (MPa if apply)
References
- S. Sevanto, T. Holtta, A. Hirsikko, T. Vesala and E. Nikinmaa, 2005, Determination of thermal expansion of green wood and the accuracy of tree stem diameter variation measurements, Boreal Environ. Res., Vol. 10, pp.437-445.
- J. Bjurman, C. B. Melin, 2017, Moisture gradients in wood subjected to relative humidity and temperatures simulating indoor climate variations as found in museums and historic buildings, J. Cult. Heritage, Vol 25, pp. 157-162. https://doi.org/10.1016/j.culher.2016.12.006
- K. Leslaw, 2016, Reinforcing wood by surface modification, Struct, Vol. 158, pp.64-71.
- Z.W. Guan, E.C. Zhu, 2009, Finite element modelling of anisotropic elasto-plastic timber composite beams with openings, Eng. Struct., Vol. 31, pp.394-403. https://doi.org/10.1016/j.engstruct.2008.09.007
- M. Oqudjene, M. Khelifa, 2009, Elasto-plastic constitutive law for wood behavior under compressive loadings, Constr. Build. Master., Vol.23, No. 11, pp.3359-3366. https://doi.org/10.1016/j.conbuildmat.2009.06.034
- Interpeo, 2016, Temperature + humidity on LCD, https://create.arduino.cc/projecthub/interpeo/temperature-humidity-on-lcd-0396b3
- RJ. Ross, 2010, Wood Handbook: Wood as an engineering material, General Technical Report