Linear Viscoelastic Wood Creep Models

Area of Science:

• Materials Science
• Wood Mechanics
• Rheology

Background:

• Wooden beams exhibit complex viscoelastic behavior under load.
• Accurate rheological models are crucial for predicting long-term performance.
• Existing simple models inadequately describe wood creep, especially under varying loads.

Purpose of the Study:

• To identify the optimal linear viscoelastic rheological model for wooden beams.
• To evaluate the performance of different rheological models under multistage loading.
• To determine the necessary model complexity for accurate wood creep prediction.

Main Methods:

• Experimental testing of full-size pine wood beams.
• Application of a long-term, multistage loading program.
• Comparison of three-, four-, five-, and six-parameter rheological models.

Main Results:

• Three- and four-parameter models are insufficient for wood creep.
• A five-parameter model adequately describes creep under constant load.
• A six-parameter model perfectly fits experimental data for multistage loading.

Conclusions:

• A six-parameter rheological model is essential for accurately describing wood creep under multistage loading conditions.
• Multistage loading experiments are critical for robust model verification.
• The complexity of the rheological model must match the loading conditions for reliable predictions.