Bridge Weigh-in-Motion (B-WIM) is the concept of using measured strains on a bridge to calculate the static weights of passing traffic loads as they pass overhead at full highway speed. Weight calculations should have a high level of accuracy to enable the B-WIM system from being a tool for direct overload enforcement. This paper describes the experimental testing of the B-WIM system based on moving force identification (MFI) theory. The bridge was instrumented by wireless accelerometers and strain gages attached to the girders to measure the dynamics response when the calibrated trucks pass the bridge. LS-Dyna finite element program is used to imitate the 3-D bridge model, which validated utilizing the collected acceleration data. Then measurements from the wireless strain sensors are utilized to run the (MFI) algorithm and calculate the truck weight.
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Bridge Damage Detection using the Inverse Dynamics Optimization Algorithm
The current methods to identify the bridge damage depend on time-consuming visual inspection and/or based on the data collected from sensor-based monitoring, which make the assessment process very expensive. In this paper, the bridge damage is identified using the data collected from an ordinary strain transducer. In order to demonstrate the new method, 3-D finite element models followed by the Inverse Dynamics Optimization Algorithm are performed. The inverse algorithm utilized to calculate the weight of the force that passes on the bridge. Any change in the bridge stiffness by damage will influence the force history which calculated by the inverse algorithm. The proposed method divided into two stages: in the first one, two finite element models are used to simulate the bridge displacement due to quarter car model one representing the healthy bridge and the other for the damage one. In the second stage, the inverse dynamics optimization algorithm used to identify the damage locations.
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- Award ID(s):
- 1645863
- NSF-PAR ID:
- 10089841
- Date Published:
- Journal Name:
- 26th ASNT Research Symposium
- Page Range / eLocation ID:
- 175-184
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Bridge Weigh-in-Motion (B-WIM) is the concept of using measured strains on a bridge to calculate the static weights of passing traffic loads as they pass overhead at full highway speed. Weight calculations should have a high level of accuracy to enable the B-WIM system from being a tool for direct overload enforcement. This paper describes the experimental testing of the B-WIM system based on moving force identification (MFI) theory. The bridge was instrumented by wireless accelerometers and strain gages attached to the girders to measure the dynamics response when the calibrated trucks pass the bridge. LS-Dyna finite element program is used to imitate the 3-D bridge model, which validated utilizing the collected acceleration data. Then measurements from the wireless strain sensors are utilized to run the (MFI) algorithm and calculate the truck weight.more » « less
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Accepted Manuscript1.0
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- The DOI is not currently available.
