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CONSIDERATII ASUPRA FORTELOR DE UMFLARE A LEMNULUI
Mihai ISPAS
Prof.dr.ing. - Universitatea TRANSILVANIA din
Brasov - Facultatea de Industria Lemnului
Adresa: B-dul. Eroilor nr.29, 500036 - Brasov,
Romania
Tel/Fax: 0040 268 419581
E-mail: ispas.m@unitbv.ro
Rezumat:
        Din cele mai
vechi timpuri, omul a cunoscut puterea umflarii
lemnului, folosind-o in scopul dizlocarii blocurilor
masive de piatra. Lucrarea prezinta rezultatele
unei cercetari experimentale referitoare la fortele
generate de umflarea lemnului de pin (Pinus sylvestris
L.) si fag (Fagus sylvatica L.). Obiectivul cercetarii
a fost determinarea valorii si evolutiei in timp
a fortelor dezvoltate prin umflare de la starea
absolut uscata pana la saturatia fibrei, de catre
epruvete de lemn de pin si fag, precomprimate
cu diverse presiuni.
        Rezultatele
pot fi utile pentru diferite aplicatii, in special
pentru domeniul constructiilor din lemn.
Cuvinte cheie: forte de umflare,
pin, fag.
Bibliografie:
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In: Wood Science and Technology, Springer Berlin
/ Heidelberg, Vol. 41, Nr. 5/June, 2007, pp. 401-415,
ISSN 0043-7719.
HOFFERBER, B. M. et al. (2006). Efectul fortelor
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February 19-22, 2006, Jacksonville, Florida; pp.
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7th edition, "Transilvania" University
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the Physical Properties of Wood) (in Russian).
Isdatelstvo Akademii Nauk SSSR, Moskva.
KOLLMANN, F.; COTE, W. A. Jr. (1984). Principles
of Wood Science and Technology. I. Solid Wood.
Reprint, Springer-Verlag, Berlin.
KRAUSS, A. (2004). Presiunea de umflare a lemnului
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umed sau apa (Swelling Pressure of Spruce Wood
Along the Grains Moistened in Humid Air or Water).
Folia Forestalia Polonica, Seria B, Zeszyt 35,
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MANTANIS, G. I. et al. (1994). Umflarea lemnului
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MISHIRO, A. (1976). Studies on the Swelling Pressure
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ROWELL, R. M. (1995). One Way to Keep Wood From
Going This Way and That. Can Chemical Treatment
Make Wood More Reliable for Instrument Makers?
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TARKOW, H.; TURNER, H. D. (1958). The Swelling
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