臺灣博碩士論文加值系統

本研究針對柳杉小型實木試片之含水率進行調控及測量，進行不同試驗溫度固定載重之短期潛變試驗，比較含水率及溫度分別對於木材短期潛變應變之影響，由試驗結果得，在試驗過程中，水分的變動會使木材出現額外的變形，整體試驗結果，以環境平衡含水率為分界，逐漸趨向於2群，透過等時線分析結果，可得到木材在固定載重之下，其潛變應變受到含水率的影響大於溫度，當木材脫濕時，會造成應變的跳升，於多因子分析結果中，可以印證機械吸附為非時變性的現象。於本研究中將木材因為含水率變化產生的額外應變以獨立的因子進行模擬，將木材的潛變行為總應變分成瞬間應變、潛變應變、機械吸附現象產生之應變3個部分進行疊加擬合，所得出的擬合曲線與以TTSP將短期潛變試驗結果進行平移之潛變主曲線相關度高，可作為木材含水率加入潛變主曲線擬合之參考模式。

In this study, to investigate the effects of moisture content and temperature on the creep behavior of Japanese cedar, a series of short-term creep tests under various conditions has been conducted. According to the short-term creep test results of groups of different temperatures and moisture contents, the changing of moisture contents affected the creep strain more obvious than the changing of temperatures did. Desorption of water would cause the deformation increased. Testing results have been departed into 2 cases and, one of them was the groups that moisture contents of specimens were lower than the equilibrium moisture content of the ambient environment and the other was that moisture contents of specimens were higher than the equilibrium moisture contents of the ambient environment. In addition, the analysis of isochrones indicated the same results as the previous researches that the mechano-sorptive behavior is time-independence. The effect of moisture contents of wood specimens had been considered being added into the model of explaining the creep behavior of wood in this study. Moreover, the total creep strain of wood could be explained using a proposed model separated into 3 parts: instantaneous strain, creep strain, and strain induced by mechano-sorptive behavior. The fitting results demonstrated that the proposed model has high correlation to the creep master curves constructed by time-temperature superposition principle (TTSP). It is possible to use this model to predict to creep behavior of wood under the situation of moisture content changing.

口試委員會審定書 #
誌謝 i
中文摘要 ii
ABSTRACT iii
目錄 iv
圖目錄 vi
表目錄 ix
壹、 前言 1
貳、 文獻回顧 2
一、 木材的基本特性 2
二、 木材的含水狀態 3
三、 木材含水率與力學行為之關連性 5
四、 機械吸附現象 7
五、 潛變 10
六、 木材含水與潛變的關係 14
七、 時溫疊加定理 21
參、 材料與方法 24
一、 研究流程 24
二、 材料 26
三、 試驗方法 26
（一） 強度試驗 26
（二） 含水率調控 26
（三） 短期潛變試驗 28
（四） 時溫疊加 30
肆、 結果與討論 32
一、 木材基本性質 32
（一） 試材密度分佈 32
（二） 強度試驗結果 33
二、 短期潛變試驗 35
（一） 十分鐘試驗 35
1. 短期潛變試驗前後含水率變動狀況 36
2. 相同含水率不同試驗溫度結果比較 39
3. 相同試驗溫度不同含水率結果比較 47
（二） 等時線 52
（三） 多因子比較 59
三、 潛變主曲線 60
（一） 時溫等效疊加 60
（二） 平移因子 61
四、 曲線擬合 62
伍、 結論 70
陸、 參考文獻 72

王松永、丁昭義（1984）林產學上冊。臺灣商務印書館股份有限公司。639頁。
王松永（1993）木材物理學。徐氏文教基金會。816頁。
Armstrong, L. D. and R. S. T. Kingston (1960) Effect of moisture changes on creep in wood. Nature. Vol.185: 862-863.
Armstrong, L. D. and G. N. Christensen (1961) Influence of moisture changes on deformation of wood under stress. Nature. 191: 869-870.
Armstrong, L. D and R. S. T. Kingston (1962) The effect of moisture content on the deformation of wood under stress. Aust J Appl Sci. 13(4): 257-276
Armstrong, L. D. and P. U. Grossman (1972) The behaviour of particle board and hardboard beams during moisture cycling. Wood Sci. Technol. 6(2): 128-137.
Betten, J. (2008) Creep Mechanics. Germany. 367 pp.
Bethe, E. (1969) Festigkeitseigenschaften von bauholz bei lagerung im wechselklima unter gleichzeitiger mechanischer belastung. Holz als Roh-und Werkstoff. 27(8): 291-303.
Bienfait, J. L. (1926) Relation of the manner of failure to the structure of wood under compression parallel to the grain. US Government Printing Office.
Bodig, J. and B.A. Jayne (1982) Mechanics of Wood and Wood Composites. Van Nostrand Reinhold Company Inc.: New York.
Bolton, A. J., P. Jardine, M. H. Vine and J. C. F. Walker (1974) The swelling of wood under mechanical restraint. Holzforschung. 28(4): 138-145.
Chang, F.-C. (2011) Creep behaviour of wood-plastic composites. The University of British Columbia. Doctor of philosophy. 230 pp.
Chang, F.-C., F. Lam, and J. F. Kadla (2013) Using master curves based on time–temperature superposition principle to predict creep strains of wood-plastic composites. Wood Sci. Technol. 47: 571–584.
Chen, M. M. (1974) Proposed explanation for the phenomenological rheology of prefrozen redwood. Wood Sci. For Prod Res Soc Madison. 7 (1): 34
Christensen, G. N. (1962) The use of small specimens for studying the effect of moisture content changes on the deformation of wood under load. Aust. J. Appl. Sci. 13(4): 242-256.
Eriksson, L. and B. Norén (1965) Effect of moisture change on deformation of wood with tension in fiber direction. Eur. J. Wood Wood Prod. 23(5): 201.
Erickson, R. W. and D. J. Sauer (1969) Flexural creep behavior of redwood heartwood during drying from the green state. For. Prod. J. 19 (12): 45
Erickson, R. W., M. M. Chen and T. Lehtinen (1972) The effect of unidirectional diffusion and prefreezing upon flexural creep in redwood. For. Prod. J. 22(10): 56-60.
Ferry, J. D. (1980) Viscoelastic Properties of Polymers. Third edition. Wiley. New York.
Fridley, K. J., R. C. Tang, and L. A. Soltis (1992) Creep behavior model for structural lumber. J. Struct. Eng. 118(8): 2261-2277.
Gibson, E. J. (1965) Creep of wood: Role of water and effect of a changing moisture content. Nature. 205: 213-215.
Grossman, P. U. A. (1976) Requirements for a model that exhibits mechano-sorptive behaviour. Wood Sci. Technol. 10(3): 163-168.
Hering, S. and P. Niemz (2012) Moisture-dependent, viscoelastic creep of European beech wood in longitudinal direction. Eur. J. Wood Wood Prod. 70: 667-670.
Hoffmeyer, P. and R. W. Davidson (1989). Mechano-sorptive creep mechanism of wood in compression and bending. Wood Sci. Technol. 23(3): 215-227.
Hearmon, R. E. S. and J. M. Paton (1964) Moisture content changes and creep of wood. For. Prod. J. 14(8): 357-359
Kitahara, K. (1964) The influence of the change of temperature on creep in bending. Mokuzai Gakkaishi. 10: 169
Kollman, F. F. P., and W. A. Côté (1968). Principles of Wood Science and Technology: Solid Wood. Allen & Unwin.
Le Huy, M. and G. Evrard (1998) Methodologies for lifetime predictions of rubber using Arrhenius and WLF models. Macromol. Mater. Eng. 261(1): 135-142.
Lee, S.-Y., H.-S. Yang, H.-J Kim, C.-S. Jeong, B.-S. Lim, and J.-N. Lee (2004) Creep behavior and manufacturing parameters of wood flour filled polypropylene composites. Compos. Struct. 65: 459-469.
Leicester, R. H. (1971) A rheological model for mechano-sorptive deflections of beams. Wood Sci. Technol. 5(3): 211-220
LeVan, S. L. and M. Collet (1989) Choosing and applying fire-retardant-treated plywood and lumber for roof designs. Gen. Tech. Rep. FPL-GTR-62. USDA Forest Serv., Forest Prod. Lab., Madison, WI.
Madsen, B. (1992) Structural Behaviour of Timber, Timber Engineering Ltd. North Vancouver. British Columbia, Canada.
Mohager, S. (1987) Studies of creep in wood. Thesis, the Royal Institute of Technology, Report TRITA-BYMA, 1.
Mohager, S. and T. Toratti (1993) Long term bending creep of wood in cyclic relative humidity. Wood Sci. Technol. 27: 49-59.
Nuñez, A. J., N. E. Marcovich and M. I. Aranguren (2004) Analysis of the creep behavior of polypropylene‐woodflour composites. Polym. Eng. Sci. 44(8): 1593-1603.
Ranta-Maunus, A. (1973) A theory for the creep of wood with application to birch and spruce plywood. Building Technology and Community Development. Technical Research Centre of Finland. Publ. 4
Ranta-Maunus, A. (1975) The viscoelasticity of wood at varying moisture content. Wood Sci. Technol. 9: 189-205.
Samarasinghe, S., J. R. Loferski and S. M. Holzer (2007) Creep modeling of wood using time-temperature superposition. Wood Fiber Sci. 26(1): 122-130.
Schniewind, A. P. (1967) Creep-rupture life of Douglas-fir under cyclic environmental conditions. Wood Sci. Technol. 1:278-288
Schniewind, A. P. and D. E. Lyon (2007) Further experiments on creep-rupture life under cyclic environmental conditions. Wood Fiber Sci. 4(4): 334-341.
Shmulsky, R. and P. D. Jones (2011) Forest Products and Wood Science. John Wiley & Sons. 466 pp.
Siau, J. F. (2012) Transport Processes in Wood (Vol. 2). Springer Science & Business Media. 256 pp.
Stamm, A. J. (1959) Bound-water diffusion into wood in the fiber direction. For. Prod. J. 9: 27-32.
Tajvidi, M., R. H. Falk and J. C. Hermanson (2005) Time–temperature superposition principle applied to a kenaf‐fiber/high‐density polyethylene composite. J. Appl. Polym. Sci. 97:1995–2004.
Tamrakar, S., R. A. Lopez-Anido, A. Kiziltas and D. J. Gardner (2011) Time and temperature dependent response of a wood–polypropylene composite. Compos. Pt. A-Appl. Sci. Manuf. 42(7): 834-842.
Xu, Y., Q. Wu, Y. Lei and F. Yao (2010) Creep behavior of bagasse fiber reinforced polymer composites. Bioresour. Technol. 101:3280-3286.
Zhou, Y., M. Fushitani, T. Kubo and M. Ozawa (1999) Bending creep behavior of wood under cyclic moisture changes. J. Wood Sci. 45:113-119.