Electronic Journal of Polish Agricultural Universities (EJPAU) founded by all Polish Agriculture Universities presents original papers and review articles relevant to all aspects of agricultural sciences. It is target for persons working both in science and industry,regulatory agencies or teaching in agricultural sector. Covered by IFIS Publishing (Food Science and Technology Abstracts), ELSEVIER Science - Food Science and Technology Program, CAS USA (Chemical Abstracts), CABI Publishing UK and ALPSP (Association of Learned and Professional Society Publisher - full membership). Presented in the Master List of Thomson ISI.
2004
Volume 7
Issue 2
Topic:
Wood Technology
ELECTRONIC
JOURNAL OF
POLISH
AGRICULTURAL
UNIVERSITIES
Krauss A. 2004. SWELLING PRESSURE OF WOOD DETERMINED FROM HYGRO-MECHANICAL CREEP MEASUREMENTS, EJPAU 7(2), #01.
Available Online: http://www.ejpau.media.pl/volume7/issue2/wood/abs-01.html

SWELLING PRESSURE OF WOOD DETERMINED FROM HYGRO-MECHANICAL CREEP MEASUREMENTS

Andrzej Krauss

 

ABSTRACT



Swelling pressure in longitudinal direction has been determined on the basis of the time dependence of intensity of hygro-mechanical creep on the stretching, by the method of Moli˝ski and Raczkowski [11]. The external stress needed for total inhibition of unidirectional spruce wood longitudinal swelling has been established. The maximum value of the swelling pressure determined on the basis of hygro-mechanical deformations of spruce wood samples simultaneously subjected to stretching in longitudinal direction and moistening is 14.4 MPa which is by 60% higher than the corresponding value found by the direct method of swelling inhibition for spruce wood sample of the same density. The probable reason for getting higher values of the maximum swelling pressure by the indirect method applied was the elimination of the sample buckling and a shortening of the time needed to reach the swelling pressure maximum, so reduction of the effects of the relaxation processes on the final result of swellin

Key words: hygro-mechanical creep, swelling pressure, spruce wood (Picea abies Karst.)..