Reaction Rate Model for the Fatigue Strength of Wood
Keywords:
Absolute reaction rate, bending strength, creep rupture, Douglas-fir, duration of load, fatigue, frequency, sinusoidal load, strength, temperature, woodAbstract
In this paper, we consider the fatigue strength of wood structural members. That is, we develop a mathematical model for time-dependent strength under sinusoidal load. This work extends the model for time-dependent strength under constant load and ramp load derived previously by two of the authors. It is based on the statistical theory of the absolute reaction rate in a version favorably reviewed in the literature. Under the isothermal condition, the model predicts that the time at fracture is independent of stress frequency. The need to evaluate experimentally some of the model parameters that may depend on stress frequency indirectly through temperature changes is discussed.References
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