Forest
Products Mechanics (6
Ects / 4ov) 3513055
Puutuotteiden mekaniikka
Petri P. Kärenlampi
Lectures 26 h, Exercises 74 h, literature and examinations 60 h
Essentials: Strain. Stress. Stress-strain relations. Transformations. Time-dependent mechanical behavior. Moisture and temperature effects.
Complementary knowledge: Irrecoverable deformations. Energy dissipation. The fracture energy.
Special knowledge: Brittleness. Strain-softening.
Student will gain ability to analyze, evaluate and develop mechanical behavior of structures, in particular those made of porous, anisotropic, hygroscopic and time-dependent materials.
Lectures 26 hours:
Monday, Wednesday, Room Bor101
6.9. 2021 8-10
Normal Strain
Normal
Stress
Stress-Strain Relations
8.9. 8-12
Volumetric Strain
Shear Strain
Shear Stress
Multiaxial
Stress and Strain States
Off-Axis Stress
and Strain
Stress and
Strain Transformations
13.9. 8-10
Time-Dependent Mechanical Behavior
15.9. 8-12
Moisture and Temperature Effects
Time-Temperature-Moisture-Specific Volume – Equivalency
20.9. 8-10
Irrecoverable Deformations
22.9. 8-12 Yield
Criterion
27.9. 8-10
Strength of Materials
The Fracture
Energy
29.9. 8-12
Brittleness and Strain-Softening
4.10. 8-10 Wood
Products Applications
6.10. 8-12
Pulping Applications
Paper and
Paperboard Applications
Any
student is free to choose either to attend in the lecture room or follow a
livestream. Learning results appear to be somewhat better on site.
livestream
address:
http://www.uef.fi/live2
The
livestream is a one-way communication system. It needs to be complemented, to
allow questions and comments. There will be an e-mail connection during the
lectures. The lecturer is available during lectures at
petri.karenlampi@gmail.com. Regular uef-email of the
lecturer is not reachable from the lecture room.
If
you follow by livestream, please let the lecturer know that you are there.
Grading:
Weekly exercises 25%
Exam 75%
There are three types of exercises.
Firstly, there are weekly exercises.
Then, there is an experimental exercise. And finally, there is a project
exercise, where each student presents a forest products application of
Mechanics.
Weekly exercises are due each Monday
at 9 am, between September 13 and October 8, to be returned to a mailbox by the
main entrance of the Borealis Building.
Reporting session for the
last weekly exercise Wednesday, October 6, 12-14 at Bor101.
Experimental exercise October 15.
Reporting Sessions for Experimental exercise on October 29th (Room N106), at 12-16.
Project exercise September-October.
Course
Literature:
Tsai, S. W. and Hahn, H. T.,
Introduction to composite materials. Technomic Publishing Co.,
Simo, J. C. and Hughes, T. J. R., Computational inelasticity. Interdisciplinary applied mathematics, Springer Verlag 1998, pp. 1-70.
Smith, T. L.,
Stress-strain-time-temperature relationship for polymers. ASTM Materials Sci.
Series 3, STP-325. American Society of Testing and Materials,
Final examination November 1, at 12-14, Room Bor100.
Possibility for eventual renewals November 15 at 12-14,
Room Bor100.
Exercises Contents:
There are three types of exercises:
1.Weekly exercises
As explained above. The approximated
time consumption is 37 hours.
2.
Implementation and analysis of mechanical experiments
The approximated time consumption of
this exercise is 24 hours, of which 2 hours in implementation of the
experiment, and 22 hours for analyzing the results.
Detailed instructions are given below.
Briefly, the exercises contain
Experimental determination of:
Small-Strain Stiffness
Stress-Strain Curve
Tangential Stiffness
Irrecoverable Strain
Thermal expansion
Large-Strain Stiffness
Energy Dissipation
The effect of the following factors on
the characteristics above
will be investigated:
Moisture Content
Straining Rate
3. Presentation of an application of
mechanics in the
The approximated time consumption of
this exercise is 13 hours, which is budgeted for the study of an application,
on the basis of literature, and the preparation of a presentation regarding it.
The presentations (each of duration 20...30 minutes, followed by discussion)
will be given during the three last sessions of the lecture program.
Any presentation of application is
supposed to based in documents identified by the
instructor. The title of the presentation is to be designed by the presenter.
The following literature is to be used as a basis of presentations. Any
participant may choose one of the following groups of references:
A/
3211. Brebner, K.
I., Schneider, M. H. and St-Pierre, L. E., Flexural strength of
polymer-impregnated eastern white pine. For. Prod. J. 35(2):22-27 (1985).
3210. Brebner, K.
I., Schneider, M. H. and Jones, R. T., The influence of moisture content on the
flexural strength of styrene-polymerized wood. For. Prod. J. 38(4):55-58
(1988).
3217. Schneider, M. H., Phillips, J. G.,
Tingley, D. A. and Brebner, K. I., Mechanical
properties of polymer-impregnated sugar maple. For. Prod. J. 40(1):37-41
(1990).
3215. Schneider, M. H., Brebner,
K. I. and Hartley,
B/
3845. English, B. W. and Falk, R. H., Factors
that affect the application of woodfiber-plastic
composites. In Proceedings: "Woodfiber-plastic
composites: virgin and recycled wood fiber and polymers for composites",
May 1-3, 1995, Madison, Wisc., pp. 189-194. Forest Products Society,
3852. Kortschot, M.
T., Engineering design and materials seclection:
principles and applications for woodfiber-polymer
composites. Fourth International Conference on Woodfiber-Plastic
Composites, May 12-14, 1997,
3835. Simonsen, J., The mechanical properties
of woodfiber-plastic composites: theoretical vs.
experimental. In Proceedings: "Woodfiber-plastic
composites: virgin and recycled wood fiber and polymers for composites",
May 1-3, 1995, Madison, Wisc., pp. 47-55. Forest Products Society,
3854. Maiti, S. N., Wood flour-polypropylene composites: structure-property
relationships. Fourth International Conference on Woodfiber-Plastic
Composites, May 12-14, 1997,
3866. Selke, S. E. and Childress, J., Wood
fiber/high-density polyethylene composites: ability of additives to enhance
mechanical properties. In:"Wood-Fiber/Polymer
Composites: Fundamental Concepts, Processes, and Material Options", Ed. M.
P. Wolcott. Forest Products Society,
4495. Stamm, A. J.,
Burr, H. K. and Kline, A. A., Staybwood – a heat
stabilized wood.
4498. Stamm,
A. J.,Thermal degradation of wood and cellulose.
4499. Stamm, A. J.
and Baechler, R. H., Decay resistance and dimensional
stability of five modified woods.
4496. Hillis, W. E., High temperature and
chemical effects on wood stability. Wood Sci. Tech.18:281-293 (1984).
4487.
4315. Kamdem, D. P., Pizzi, A. and Jermannaud, A.,
Durability of heat-treated wood. Holz als Roh- un Werkstoff
60(1):1-6 (2002).
4489. Thermowood. Finnish thermowood
association.
http://www.thermowood.fi/pdf/thermowood_english.pdf
E/
4490. Inoue, M., Norimoto,
M., Tanahashi, M. and Rowell, R. M., Steam of heat
fixation of compressed wood. Wood Fiber Sci.
25:224-235 (1993).
4491.
Ito, Y., Tanahashi, M., Shigematsu,
M., Shinoda, Y. and C. Ohta, C., Compressive-Molding of
wood by high-pressure steam-treatment: Part 1. Development of compressively molded squares from thinnings. Holzforschung 52:211-216 (1998).
4492. Ito, Y., Tanahashi, M., Shigematsu, M. and
Shinoda, Y., Compressive-molding of wood by
high-pressure steam-treatment: Part 2. Mechanism of permanent fixation. Holzforschung
52:217-221 (1998).
4103. Tanahashi, M., Kyomori, K., Shigematsu, M. and Onwona-Agyeman, S., Development of compressive molding
process of wood by high-pressure steam and mechanism of permanent fixation for
transformed shape. Fist International Conference of the European Society of
Wood Mechanics, April 19-21, 2001,
4104. Heger, F., Girardet, F., Moeckli, P. and
Navi, P., Thermo-hydro-mechanical demsification and
influence of post-treatment on set-recovery. Fist International Conference of
the European Society of Wood Mechanics,
April 19-21, 2001,
4466. Wallström, L., Lindberg, K. A. H. and Johansson,
4467. Wallström, L., and Lindberg, K. A. H., Wood surface stabilization with polyethylene glycol, PEG. Wood Sci. Tech. 29:109-119 (1995).
4465. Wallström, L., and Lindberg, K. A. H., Measurement of cell wall penetration in wood of water-based chemicals using SEM/EDS and STEM/I. Wood Sci. Tech. 33(2):111-122 (1999).
G/
4386. Kifetew, G.,Thuvander, F., Berglund, L. A. and Lindberg, H., The effect of drying on wood fracture surfaces from specimens tested in wet condition, Wood Sci. Tech. 32(2):83-94 (1998).
4034. Thuvander, F., Wallström, L., Berglund, L. A. and Lindberg, K. A. H.,
Effects of an impregnation procedure for prevention of wood cell wall damage
due to drying. Wood Sci. Tech. 34(6):473-480
(2001).
H/
3512.
Björkqvist, T., Menetelmä ja laite puun mekaaniseksi kuiduttamiseksi. Förfarande och anordning för
mekanisk defibrering av trä. Finnish Patent 98148 (1995). WO9638624:
Method and apparatus for mechanical defibration of wood, published 1996-12-05.
4230.
Björkqvist, T. and Lucander,
M., Grinding surface with an energy-efficient profile. 2001 International
Mechanical Pulping Conference, Helsinki, Finland, June 4-8, 2001, pp. 373-380.
I/
4473. Kärenlampi, P. P., Tynjälä, P. and Ström, P.: Molecular fatigue in cell walls. 2002 Paper Physics Seminar, Finger Lakes, NY, Sept. 8-13, pp. 240-243
4377. Kärenlampi, P. P., Tynjälä, P. and Ström, P., Molecular reorganization in wood. Mechanics of Materials 35(12):1149-1159 (2003).
4322. Kärenlampi, P. P., Tynjälä, P. and Ström, P., Molecular fatigue in steamed wood. Int. J. Fatigue 25(6):489-497 (2003).
4249. Kärenlampi, P. P., Tynjälä, P. and Ström, P., Off-axis fatigue loading of steamed wood. Int. J. Fatigue 24(12):1235-1242 (2002).
J/
2623. Östlund, S., Niskanen, K. and
Kärenlampi, P., On the prediction of the strength of paper structures with a
flaw. J. Pulp Paper Sci. 25(10):353-360 (1999).
K/
3579. Östlund, S. and Kärenlampi, P., Structural geometry effect on the size-scaling of strength. Int. J. Fract. 109(2):141-151 (2001).
L/
2661. Tryding, J. and
Gustafsson, P. J., Characterisation of tensile
fracture properties of paper. Tappi 83(2):84-89
(2000).
3622. Tryding, J. and
Gustafsson, P. J., Analysis of notched newsprint sheet in mode I fracture. J.
Pulp Paper Sci. 27(3):103-109 (2001).
M/
3342. Uesaka, T. and Ferahi, M.,
Principal factors controlling press room breaks. 1999 Paper Physics Conference,
4486. Uesaka, T., Ferahi, M., Hristopulos, D., Deng, N. and Moss, C., Factors controlling
press room runnability of paper . 12th Fundamental Research Symposium,
4452.
Hristopoulos, D. T. and Uesaka, T., Model of
machine-direction web dynamics and impact on web brake rates. PPP2002, Progress
in Paper Physics Seminar, Finger Lakes /
N/
3362. Wahlström, T., Adolfsson, K., Östlund, S. and Fellers, C., Numerical modeling of the
cross direction shrinkage profile in a dryer section. A first approach. 1999
Paper Physics Conference,
O/
2976. Glynn, P., Jones, H. W. H. and Gallay, W., The fundamentals of curl in paper. Pulp Paper
2973. Gray, D. G.,
Chirality and curl in paper sheets. J. Pulp Paper Sci. 15(3):J105-109 (1989).
4458. Östlund, M., Östlund, Ö., Carlsson, L. A. and Fellers, C., Experimental determination of residual stresses in paperboard. PPP2002, Progress in Paper Physics Seminar, Finger Lakes / Syracuse, NY, Sept. 8-13, 2002, pp. 180-183..
4443. Persson,
M. and Wahlström, T., The development of moisture
gradients using different stategies and their
influence on process-induced curl. PPP2002, Progress in Paper Physics Seminar,
Finger Lakes /
P/
4841. Stanzl-Tschegg, S. E., Microstructure and fracture mechanical response of wood. Int. J. Fract. 139:495-508 (2006).