Original scientific paper
Creep of timber structures
Jože Lopatič
; Faculty of Civil and Geodetic Engineering, University of Ljubljana, Ljubljana, SLOVENIA
Drago Saje
; Faculty of Civil and Geodetic Engineering, University of Ljubljana, Ljubljana, SLOVENIA
Franc Saje
; Faculty of Civil and Geodetic Engineering, University of Ljubljana, Ljubljana, SLOVENIA
Abstract
Apart from the criterion of load capacity, the criterion of deformability is very often a decisive one in designing timber structures. Displacements of the structure should stay within the limits so that its functionality could be assured during the entire service life in order that they do not cause damage to non-bearing elements of the structure and equipment and do not have negative psychological impact on the user. There, however, it should be kept in mind, the displacements of the structure include initial elastic displacements and displacements due to the creep of timber, normally emerging during a longer period of time. The creep of timber consists of three parts that appear simultaneously which can hardly be distinguished from one another. Those are time dependent viscoelastic creep, mechano-sorptive creep and the pseudo creep and recovery. The numerical analysis of the response of structure to long-term loading allows the time dependent increase in the displacements of structure due to the creep of timber to be determined. In this article, the mathematical modelling of the timber creep by using mechanical models is presented. The creep parameters applied in the numerical simulation of this phenomenon have been obtained through long-lasting experimental research. The application of the developed method of numerical analysis of time dependent response of timber structures, taking into consideration the viscous creep and mechano-sorptive creep, is illustrated by calculation examples. Good correlation of the results obtained by calculation with those obtained experimentally verifies the suitability of both the calculation method and the developed software.
Keywords
timber structures, creep, four-point bending test
Hrčak ID:
295348
URI
Publication date:
15.12.2005.
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