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Madison, WI 53726-2398
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Title: Assessment and maintenance of a 15 year old stress-laminated timber bridge

Source: Proceedings of the 7th International Conference on Short and Medium Span Bridges 2006, 2006 August 23-25, Montreal, Quebec, Canada. Montreal, Quebec, Canada : Canadian Society for Civil Engineering: pages RE-012-1--RE-012-10.

Author(s)Gentry, T. Russell; Brohammer, Karl N.; Wells, John; Wacker, James P.

Publication Year: 2006  View PDF »

Category: Journal Articles

Abstract: A timber bridge consisting of three 6.7 meter spans with a stress laminated deck was constructed in 1991 in the Spirit Creek State Forest near August, Georgia, USA. The stress laminated bridge uses a series of post-tensioning bars to hold the laminations together. The bridge remained in service until 2001 with no maintenance, at which time the bridge was inspected, load tested and the post-tensioning bars re-stressed. In 2005, the bridge was again inspected, load tested, and the bars were re-tensioned. This paper reports on results of the inspection and load tests. The overall condition of the bridge is reported, along with details on the moisture condition, overall deck deflection and timber strains under load. Details on the loss of post-tensioning forces in the bars, and an investigation of the causes of this loss, are presented.

Keywords: Laminated wood, bridges, floors, nondestructive testing, dead loads, testing, inspection, wooden bridges, moisture, glulam timbers, static loads, laminated bridges, stress-laminated bridges, timber bridges

File size: 463 kb(s)

This publication is also viewable on Treesearch:  view
RITS Product ID: 24040
Current FPL Scientist associated with this product
Wacker, James P.
Research General Engineer

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