Abstract
Theoretical study was made on the basis of experimental data that were obtained under both linear and nonlinear load magnitudes as presented in a previous paper. Creep compliances and the nonlinear strees functiong were determined for wood specimens of different elastic moduli. It was observed that they both were larger for wood of smaller elastic modulus. A model was proposed which gives satisfactory decriptions of the creep behaviour of wood under a large range of loading magnitude in complex varying environment. The values and the dependence on some important quantities of the mechano-sorptive coefficients used in the model were determined. The coefficients, which may be regarded as a measure of the intensity of the mechano-sorptive effect, increased with the rise of the load magnitude as well as with the fall of elastic modulus.
Zusammenfassung
Theoretische Untersuchungen wurden auf der Grundlage früher beschriebener Versuchsergebnisse unternommen, die sowohl lineare als auch nichtlineare lastabhängigkeiten zeigten. Das Kriechverhalten und die nichtlineare Spannungsfunktiong wurden für Holz proben mit unterschiedlichenE-Moduls bestimmt. Ein vorgeschlagenes Berechnungs modell beschreibt zurfriedenstellend das Kriechverhalten von Holz über einen großen Belastungsbereich und unter stark wechselnden Umgebungsbedingungen. Die Zahlenwerte und Abhängigkeiten einiger wichtiger Sorptions-Koeffizienten, die als maß für die Größe des mechanisch-sorptiven Effektes angesehen werden können, steigen mit der Zunahme der Belastung und der Abnahme desE-Moduls an.
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Liu, T. Creep of wood under a large span of loads in constant and varying environments. Holz als Roh-und Werkstoff 52, 63–70 (1994). https://doi.org/10.1007/BF02615022
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DOI: https://doi.org/10.1007/BF02615022