Creep Behavior Model for Structural Lumber
Publication: Journal of Structural Engineering
Volume 118, Issue 8
Abstract
An existing four‐element viscoelastic model is used to model the creep response of lumber as a function of load and is modified to account for thermal and moisture effects, including mechanosorptive effects (i.e., the nonlinear interaction between applied stress and changing moisture content reflected in the creep response of wood). Creep data from a large population of Douglas fir nominal 2‐in.‐by‐4‐in. (38.1‐mm‐by‐88.9‐mm) lumber are used to calibrate the model. The lumber is actually tested to failure as part of a parent load‐duration (creep‐rupture) study, but the time‐dependent deflections are also monitored. The purpose for monitoring and evaluating the creep behavior of the lumber is to provide insight into the long‐term behavior of lumber and develop a general creep model that accounts for load and hygrothermal effects.
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Information & Authors
Information
Published In
Journal of Structural Engineering
Volume 118 • Issue 8 • August 1992
Pages: 2261 - 2277
Copyright
Copyright © 1992 ASCE.
History
Published online: Aug 1, 1992
Published in print: Aug 1992
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