Load-Duration Behavior of Wood-Plastic Composites
Publication: Journal of Materials in Civil Engineering
Volume 15, Issue 6
Abstract
The load-duration, or creep-rupture, behavior of wood and wood composite products has been studied extensively by numerous researchers, and simplified design procedures to account for creep effects are in place. However, the load-duration behavior of composite products made out of the combination of wood and plastic is not well understood or documented. Currently, wood-plastic composite (WPC) products are available on the commercial market, yet no standardized design procedures to account for creep or load-duration effects exist. Given the lack of understanding of the load-duration behavior of wood-plastic composites, a research effort was initiated to investigate the load-duration behavior of various wood-plastic composite formulations and to compare the observed behavior to that of solid sawn lumber. It was found that the wood-plastic composite formulations tested exhibited a more pronounced load-duration response than that of solid wood; however, the behavior trend was similar to that of solid wood and was successfully modeled using an exponential damage rate model originally developed for solid wood. Existing procedures for developing load-duration design adjustment factors for wood were used to develop load-duration design adjustment factors specifically for the WPC formulations tested.
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Information & Authors
Information
Published In
Journal of Materials in Civil Engineering
Volume 15 • Issue 6 • December 2003
Pages: 524 - 536
Copyright
Copyright © 2003 American Society of Civil Engineers.
History
Received: Jun 26, 2001
Accepted: Dec 12, 2002
Published online: Nov 14, 2003
Published in print: Dec 2003
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