Restoration of exact design for partial compression perpendicular to the grain

Abstract

To correct the empirical design rules for locally loaded beams and blocks of Eurocode 5, the theoretical explanation of these rules and of the applied test data is given. It appears that the design rule may be far too conservative, or too unsafe in other cases, and only approximately applies for thin long bearing blocks and not for the short test specimens and support stresses of beams. The theory of the determining influence of load spreading possibility on the strength is verified by all other sufficient extended investigations leading to simple and reliable design rules.

Keywords:

• Timber
• limit state analysis
• failure criterion
• compression strength of locally loaded blocks
• stress spreading model of the triaxial compression strength based on shear failure of the matrix