Eighth Congress on Forensic Engineering
Examination of Wood Truss Failures by Creep Rupture
Publication: Forensic Engineering 2018: Forging Forensic Frontiers
ABSTRACT
Wood truss members that have been in service for decades can sometimes fracture unexpectedly under normal service loading, often with little more than the dead load of the truss and supported building elements. When wood members are subject to relatively high stresses over long periods of time, a reduction in strength of the wood member can occur, especially when the imposed dead load is high relative to the allowable design load. Creep rupture occurs when load duration effects cause a sufficient loss of strength to result in fracture. This paper examines the following: 1) The basis for load duration failure models and what they predict. 2) How allowable design values are derived, how they have changed, and how load duration is accounted for. 3) How time to failure under sustained loading can be predicted. 4) Example case studies of wood truss elements that have fractured due to load duration effects.
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Information & Authors
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Published In
Forensic Engineering 2018: Forging Forensic Frontiers
Pages: 930 - 939
Editors: Rui Liu, Ph.D., Kent State University, Michael P. Lester, Element Analytical, Alicia E. Díaz de León, and Michael J. Drerup
ISBN (Online): 978-0-7844-8201-8
Copyright
© 2018 American Society of Civil Engineers.
History
Published online: Nov 27, 2018
Published in print: Nov 27, 2018
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