An improved model for the time-dependent material response of wood under mechanical loading and varying humidity conditions

Timber is one of the most widely applied engineering materials due to its favorable physical and mechanical characteristics. Nevertheless, over service life, combination load varying environmental conditions can have a critical influence on response timber structures, considering especially mechano-sorptive In this work, performance analysis existing time- moisture-dependent models identifies need more comprehensive 3D constitutive rheological model, which take into account orthotropic, elastic-plastic, viscoelastic aspects, including complex recovery phases that may occur lifetime. Therefore, algorithm such model developed here. An improvement made for component by introducing an ordinary transcending part, are governed absolute change moisture content exceeding historical highest at each loading phase, respectively. Simulations run under cases with tension compression perpendicular parallel direction fibers. Both medium-term (up 2500 h) as well short-term 350 behavior material constant temperature analyzed good agreements achieved literature results. Comparison indicates proposed gives improved prediction creep recovery, has non-linear dependence history. Furthermore, sensitivity analyses performed applicability different species combinations variation studied