LCF5852 - Physical and Mechanical Properties of Wood

Credit hours

Instructor
José Nivaldo Garcia

Objective
Develop student's perception for the application of the properties obtained from wood test specimens and motivate him/her to reflect on the reliability of mechanical tests, in such a way to discover the pure properties.
Focus on the natural variability of the basic properties of wood within forest populations according to their nature (native or planted), age, species, growth rate, etc., and encourage the discussion of its cause and the appropriate control techniques within forest management and improvement.
Apply destructive and non-destructive tests and discuss the advantages, disadvantages, similarities and differences of the results obtained;
Present technologies applied to the changing of physical and mechanical properties of wood toward new and non conventional uses.

Content
1. Verification of the functioning of wooden structures under applied loads;
2. Identification of 4 physical and 4 mechanical properties responsible for the functioning of these structures;
3. Destructive and non-destructive tests;
4. Installation of experiments to obtain each of these properties, focusing on: definition of the experimental design, pre-sampling, physical and mechanical tests, statistical analysis of data, presentation of results in the form of a seminar;
5. Defects associated to the physical and mechanical properties of wood: Growth stress, reaction wood, juvenile wood, knots, pith, cracks, warping, shrinkage, twisting;
6. Study of the variability of these properties and their associated defects in planted forests: a) in the tree: longitudinal and radial, b) in the site: between classes, between trees, c) in the population: between strata, d) in the species: between populations;
7. Control over physical and mechanical properties: through forest management, forest improvement, technologies for transforming roundwood into sawn wood, technologies for using forest products;
8. Genetic parameters: heritability of technological properties, selection gains;
9. Technology for modifying physical and mechanical properties: heat treatment, surface activation, microwaves, wood densification, lignin plasticization by temperature;
10. Tests on defect-free specimens and structural sizes;
11. Engineered wood, EGP, Glulam, VLC, CLT, I-beam;
12. Wood houses and social constructions;
13. Precious wood floor on planted wood base;
14. Use of NIRS for quick prediction of main wood properties;
15. Uses of AI (Chat GPT, Gemini, Copilot, Claude, Bardeen, Deep Seek, Gamma, others,) on the preparation of projects, presentations (lectures, classes, speeches), technical reports, academic texts and scientific papers.

Bibliography
ENTWISTLE, K. et al. The effect of saw kerf width on the value of the axial growth stress measured by splitting a log along its axis. Wood Material Science and Engineering, v. 11, n. 1, p. 1–12, 2016.
CHAUHAN, S.; ENTWISTLE, K. Measurement of surface growth stress in Eucalyptus nitens maiden by splitting a log along its axis. Holzforschung, v. 64, n. 2, p. 267–272, 2010.
PANSHIN, A. J. & ZEEUW, C. Textbook of Wood Technology. New York, 3 ed. McGrawn - Hill. vl. 1970. 705 p.
PFEIL, W. Estruturas de Madeira: dimensionamento segundo as normas brasileiras NB 11 e os modernos critérios das normas alemãs e americanas. Rio de Janeiro, Livros Técnicos e Científicos. 1978. 253 p.
POLGE, H. Utilisation des spectres de diffraction des rayons X pour les études de qualité du bois. Nancy, 1966 (Thesis - Doctorate - UN/Fr.). 215 p.
POST, I. L. An investigation of the longitudinal growth stresses in Trees. New York, 1979 (Thesis - Doctorate - SUNY/USA). 108 p.
Schacht, L. & Garcia, J. N. Variação entre e intra clones nas rachaduras de topo em Eucalyptus urophylla S. T. Blake. Colombo: EMBRAPA, 1997. V. 3, p. 401-404. IUFRO. Conference on Silvilculture and
Improvement of Eucalyptus, Salvador, 1997.
Schacht, L. & Garcia, J. N. Variação genética de indicadores de tensões de crescimento em clones de Eucalyptus urophylla. Colombo: EMBRAPA, 1997. V. 3, p. 405-410. IUFRO. Conference on Silvilculture and Improvement of Eucalyptus, Salvador, 1997.
TIMOSHENKO, S. Mecânica Técnica. Rio de Janeiro, 3 ed. Livros Técnicos e Científicos. 1979. vl.
TIMOSHENKO, S. Resistência dos Materiais. Rio de Janeiro, livros Técnicos e Científicos. 1979. 2v.
TIMOSHENKO, S. & GOODIER, J. N. Teoria da Elasticidade. Rio de Janeiro, Guanabara. 1980. 545 p.
WALLIS, N. K. Australian Timber Handbook. Sydney, Halstead. 1963. 391 p.
WILKINS, A. P.; KITAHARA, R. Silvicultural treatments and associated growth rates, growth strains and wood properties in 12.5-year-old Eucalyptus grandis. Australian Forestry, V. 54, n.1/2, p.99-104, 1991.
Balboni, B. M.; Wessels, C. Brand; Ribeiro, M. L.; Garcia, J. N. 2023a. Investigating the use of bow for prestressing lamellas of glulam beams made with young Eucalyptus grandis timber. Construction and Building Materials, 362, p. 129725.
CEN. 2018. Timber Structures – Cross laminated timber – Requirements. EN 16351.
Arriaga F, Wang X, Íñiguez-González G, Llana DF, Esteban M, Niemz P. Mechanical Properties of Wood: A Review. Forests. 2023; 14(6):1202. https://doi.org/10.3390/f14061202.
Forest Products Laboratory. 2021. Wood handbook—wood as an engineering material. General Technical Report FPL-GTR-282. Madison, WI: U.S. Department of Agriculture, Forest Service, Forest Products Laboratory. 543 p.
ASSOCIAÇÃO BRASILEIRA DE NORMAS TÉCNICAS. ABNT NBR7190: 2022 – Part 1: Design of Timber Structures.
ASSOCIAÇÃO BRASILEIRA DE NORMAS TÉCNICAS. ABNT NBR7190: 2022 Timber Structures - Part 2: Test Method; Structural timber. Grading. Requirements for visual and mechanical grading standards.
ASSOCIAÇÃO BRASILEIRA DE NORMAS TÉCNICAS. ABNT NBR7190: 2022 Timber Structures – Part 3: Test Method for clear samples.
ASSOCIAÇÃO BRASILEIRA DE NORMAS TÉCNICAS. ABNT NBR7190: 2022 Part 4: Design of Timber Structures –Test Method - Structural timber. Strength classes.
ASSOCIAÇÃO BRASILEIRA DE NORMAS TÉCNICAS. ABNT NBR7190: 2022 Timber Structures – Part 5: Test Method for structural timber. Grading. Requirements for mechanical connections.
ASSOCIAÇÃO BRASILEIRA DE NORMAS TÉCNICAS. ABNT NBR7190: 2022 Timber Structures – Part 6: Test Method - Structural Glulam members. Requirements delamination, shear glue line.
Gril, J., Jullien, D., Bardet, S. et al. Tree growth stress and related problems. J Wood Sci 63, 411–432 (2017). https://doi.org/10.1007/s10086-017-1639-y.
Journals: Australian Forestry, Australian Forestry Industry Journal, Australian Journal of Applied Science, Australian Journal of Scientific Research. Canadian Journal of Forest Research, Forest Products Journal Forest Science, Holz Alz Roh - Und Werkstoff, Holzforschung, Scientia Forestalis, IUFRO Proceedings, South African Forestry Journal, Wood and Fiber Science, Wood Science and Technology, Wood Material Sciences and Engineering, Construction and Building Materials, Forests, Forestry.