Searching for just a few words should be enough to get started. If you need to make more complex queries, use the tips below to guide you.
Article type: Research Article
Authors: Connor, R.J. | Hodgson, I.C. | Fisher, J.W.
Affiliations: ATLSS Engineering Research Center, Lehigh University, 117 ATLSS Drive, Bethlehem, PA, USA | Department of Civil and Environmental Engineering, Lehigh University, 117 ATLSS Drive Bethlehem, PA, USA
Note: [] Corresponding author. Email: rjc3@lehigh.edu
Abstract: Several tied arch and truss bridges have experienced horizontal floorbeam cracking in the region of the upper web-to-flange weld or in the web gap between the top flange and the connection angles where simple web shear connections have been used. A recent study on a 189 m (620 ft) span tied arch bridge located in Pittsburgh, Pennsylvania over the Monongahela River has evaluated the cause of this type of cracking and resulted in an effective retrofit strategy. Remote monitoring of two retrofitted floorbeam connections was conducted for a period of almost 40 days as random vehicles crossed the bridge. The measurements have confirmed that the primary cause of the observed cracking is the relative longitudinal displacements between the top flange of the floorbeam and the face of the tie girder. This relative movement was focused within the horizontal web gap between the connection angles and the bottom of the top flange. This resulted in the development of horizontal fatigue cracks along the web-to-flange weld in the floorbeam. Several cracks were observed to branch and begin to turn downward into the web. In order to alleviate this problem, a portion of the floorbeam and connection angles were removed at the top of the connection in order to provide sufficient flexibility to allow the required movement and reduce stresses. Instrumentation consisting of strain gages and LVDTs (displacement sensors) was installed at the upstream and downstream side of an interior floorbeam and used to verify the performance and effectiveness of the retrofit. The exact geometry of the retrofit was determined through a parametric finite element study, which was subsequently confirmed with field-measured data. The retrofit provides sufficient flexibility at the connection without producing high stress ranges at critical locations.
Keywords: Fatigue, Tied arch bridge, Field testing, Retrofit
DOI: 10.1080/15732480500282394
Journal: Bridge Structures, vol. 1, no. 3, pp. 177-193, 2005
IOS Press, Inc.
6751 Tepper Drive
Clifton, VA 20124
USA
Tel: +1 703 830 6300
Fax: +1 703 830 2300
sales@iospress.com
For editorial issues, like the status of your submitted paper or proposals, write to editorial@iospress.nl
IOS Press
Nieuwe Hemweg 6B
1013 BG Amsterdam
The Netherlands
Tel: +31 20 688 3355
Fax: +31 20 687 0091
info@iospress.nl
For editorial issues, permissions, book requests, submissions and proceedings, contact the Amsterdam office info@iospress.nl
Inspirees International (China Office)
Ciyunsi Beili 207(CapitaLand), Bld 1, 7-901
100025, Beijing
China
Free service line: 400 661 8717
Fax: +86 10 8446 7947
china@iospress.cn
For editorial issues, like the status of your submitted paper or proposals, write to editorial@iospress.nl
如果您在出版方面需要帮助或有任何建, 件至: editorial@iospress.nl