Experimental load rating of a steel girder bridge using structural health monitoring and modeling

For assessment of existing bridges, load rating is usually performed to assess the capacity against vehicular loading. Codified load rating can be conservative if the rating is not coupled with the field data or if simplifications are incorporated into assessment. Recent changes made to the Australian Bridge assessment code (AS 5100.7) distinguish the difference between design and assessment requirements, and include addition of structural health monitoring for bridge assessment. However, very limited guidelines are provided regarding higher order assessment levels, where more refined approaches are required to optimize the accuracy of the assessment procedure. This article proposes a multi-tier assessment procedure for capacity estimation of existing bridges using a combination of structural health monitoring techniques, advanced nonlinear analysis, and probabilistic approaches to effectively address the safety issues on aging bridges. Assessment of a Box Girder bridge was carried out according to the proposed multi-tier assessment, using data obtained from modal and destructive testing. Results of analysis at different assessment tiers showed that both load-carrying capacity and safety index of the bridge vary significantly if current bridge information is used instead of as-designed bridge information. Findings emerged from this study demonstrated that accuracy of bridge assessment is significantly improved when structural health monitoring techniques along with reliability approaches and nonlinear finite element analysis are incorporated, which will have important implications that are relevant to both practitioners and asset managers.

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Design of a Long-Term Monitoring System for a PSC Continuous Box-Girder Bridge

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.619.1 ◽

2014 ◽

Vol 619 ◽

pp. 1-9 ◽

Cited By ~ 3

Author(s):

Chuang Chen ◽

R. Kaloop Mosbeh ◽

Zong Lin Wang ◽

Qing Fei Gao ◽

Jun Fei Zhong

Keyword(s):

Structural Health Monitoring ◽

Monitoring System ◽

Health Monitoring ◽

Continuous Monitoring ◽

Variable Cross ◽

Box Girder ◽

Structural Health ◽

Box Girder Bridge ◽

Girder Bridge

Structural Health Monitoring is becoming an increasingly common tool to obtain the long-term performance of infrastructures and buildings. Many structural health monitoring systems were developed and applied to different bridges in the world. However, very little is known on the applications in extreme cold environment. Fu Sui Bridge, a 1070 m variable cross-section continuous box-girder bridge, is located in the coldest province -- Heilongjiang province, China. In order to monitor the static and dynamic responses of the bridge under the traffic and environmental variation, a long-term continuous monitoring system was designed and installed on Fu Sui Bridge in April 2012. A hydrostatic leveling system was used to measure the displacement and fiber Bragg grating sensors were used to measure strain, acceleration and temperature. Moreover, other necessary components including data acquisition and transmission, data calculation and analysis software are also described. Summer and winter monitoring data are also presented. This paper focuses on: (1) the design and installation of the long-term continuous monitoring system hardware and (2) the operating pattern and function of the automatic monitoring system. After more than one year successful conducting, the system has provided a large amount of data records for daily management and research of the bridge. This system can be applied to extremely cold region.

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