Numerical simulation of the ductile failure of mechanically and moisture loaded wooden structures

Wooden structures are always exposed to climate changes. Since all its mechanical properties are moisture-dependent, the influence of moisture content on the mechanical behavior has to be considered for a realistic simulation. A hygro-mechanically coupled macroscopic material model for use within the framework of the FEM is introduced. Thereby, moisture diffusion, hygro-expansion and moisture-dependent linear elastic behavior and ductile failure are covered. The tangent matrix required for the Newton procedure is derived completely. The model is applied to the simulation of experiments for the determination of the swelling pressure of spruce.

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