FORECASTING THE STRENGTH OF WOODEN STRUCTURES BY METHODS OF FRACTURE MECHANICS

Authors:

Galina E. Okolnikova,Elena F. Shaleeva,

DOI NO:

https://doi.org/10.26782/jmcms.spl.9/2020.05.00009

Keywords:

Fracture mechanics,stress intensity factor,crack resistance,wooden structures,,

Abstract

The article analyzes the operation of wood in the elements of real structures by the methods of the theory of elasticity and the methods of fracture mechanics; six types (systems) of crack development in the elements of wooden structures are considered, the anisotropy of wood is also taken into the account; The parameters of fracture mechanics for wooden beams with cuts were experimentally determined; values of stress intensity factors for pine wood were determined, graphical dependencies between stress intensity factors and notch depth for different crack opening models were also constructed, calculation results were compared using materials resistance methods (elasticity theory), fracture mechanics methods and experimental results; the conclusion is drawn about the applicability of linear fracture mechanics for predicting the strength of wooden structures.

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