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BUILDING STRUCTURES, BUILDINGS AND FACILITIES
Determination Of The Long-Term Modulus Of Wood Elasticity During Bending
UDC 624.011. 1:539.32(083.75) DOI: 10.33622/0869-7019.2022.02.10-13
Dmitriy K. ARLENINOV, e-mail: dkarleninov@mail.ru
Moscow State University of Civil Engineering (National Research University), Yaroslavskoe shosse, 26, Moscow 129337, Russian Federation
Abstract. For the calculation of wooden structures according to a deformed scheme in a linear setting, a constant value of the long-term modulus of elasticity, which was obtained from the results of long-term tests of samples at maximum design loads, was fixed in the norms forty years ago. In the latest edition of the norms, this indicator was slightly changed, but remained a constant value, i.e. independent on the stress level, although at present the level of computer technology makes it possible to more accurately take into account the value of the long-term elastic modulus when calculating. It is proposed to replace the constant value of this modulus of elasticity by its variable values depending on the level of stresses, for individual intervals along the length of the spans of bent and compressed-bent elements. To obtain these values, a new technique was developed for long-term testing of beam specimens in the "bending" mode. Trial tests, the results of which confirmed the dependence of the long-term modulus of elasticity on the level of stress, are presented. It is planned to carry out large-scale studies in a room with a stable temperature and humidity regime, in order to include in the design standards a "ruler" of variable values of the long-term modulus of elasticity of wood for stress intervals of 1 MPa along the span.
Key words: wooden structures, deflection, deformed scheme, long-term modulus of wood elasticity, creep of wood.
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For citation: Arleninov D. K. Determination of the Long-Term Modulus of Wood Elasticity During Bending. Promyshlennoe i grazhdanskoe stroitel'stvo [Industrial and Civil Engineering], 2022, no. 2, pp. 10-13. (In Russian). DOI: 10.33622/0869-7019.2022.02.10-13.

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