Weigh-in-Motion-Based Live-Load Fragility Analysis for a Steel Girder Bridge Using Structural Health Monitoring System
This paper presents Weigh-In-Motion (WIM)-based live-load fragility curves that enable to quantify probabilistic structural integrity of an existing highway steel bridge under multiple truck passages with uncertain characteristics. These curves defined as the probability that a bridge exceeds a certain limit state given a set of external live loads have been created using the bridge load ratings that can be calculated from a best fit regression model. The regression model is able to be identified via analytical modeling techniques incorporating the bridge response quantities resulting from ambient trucks through structural health monitoring system. These quantities coupled with WIM data obtained from two weigh stations closest to the bridge are used to 1) determine which unknown ambient trucks are most likely to cross the bridge and 2) to identify the probable characteristics of the trucks and the corresponding load ratings according to the American Association of State Highway and Transportation Officials (AASHTO) Manual. With this information, the regression models can be made to demonstrate load ratings as the truck characteristics change. Based on the best fitted load ratings, nine significant truck characteristics were looked at in their role in causing a below satisfactory bridge capacity. These truck characteristics correspond to the weight of the five axles and the four spacings between them. The nine variables were then analyzed graphically and statistically to determine which ones most significantly affect its respective fragility curve. Key findings reveal that the all axle weights affect the fragility curves though the axle weights are not significantly different and the most significant axle spacing is the first spacing. The proposed framework that can be used to post a highway bridge may be also applied to determine if changes to state legal loads, routine permit or AASHTO design loads are needed.
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Supplemental Notes:
- This paper was sponsored by TRB committee AFF20 Standing Committee on Steel Bridges.
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Corporate Authors:
500 Fifth Street, NW
Washington, DC United States 20001 -
Authors:
- Seo, Junwon
- Hatfield, Gary
- Kimn, Jung-Han
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Conference:
- Transportation Research Board 95th Annual Meeting
- Location: Washington DC, United States
- Date: 2016-1-10 to 2016-1-14
- Date: 2016
Language
- English
Media Info
- Media Type: Digital/other
- Features: Figures; Photos; References; Tables;
- Pagination: 17p
- Monograph Title: TRB 95th Annual Meeting Compendium of Papers
Subject/Index Terms
- TRT Terms: Girder bridges; Live loads; Load factor; Regression analysis; Steel bridges; Structural health monitoring; Trucks; Weigh in motion
- Subject Areas: Bridges and other structures; Highways; Maintenance and Preservation;
Filing Info
- Accession Number: 01592685
- Record Type: Publication
- Report/Paper Numbers: 16-1109
- Files: PRP, TRIS, TRB, ATRI
- Created Date: Mar 4 2016 5:04PM