An algorithm has been developed to determine deformations of a cantilever honeycomb plate under arbitrary loading conditions. The algorithm utilizes strain information from a set of sixteen fiber Bragg grating sensors, mounted on the plate so that all sensors measure strains along the clamped-free direction. The sensors are interrogated using a wavelength-division multiplexing scheme. A two-dimensional bi-polynomial function which represents the strain field is created using a least-squares algorithm. This ...
We describe an instrumentation system which provides the capability to monitor a large number of Bragg gratings using a common source and a scanning narrowband filter. The system described has the capability to monitor 12 FBG sensors along each of 5 fibers for a total of 60 sensor elements. We demonstrate the use of this system to address multiple sensors embedded in and attached to a quarter scale bridge span. ...
We describe a fiber optic Bragg grating distributed strain sensor for large scale structural monitoring applications, such as bridge monitoring. The system is capable of assessing both long term static structural loading changes and dynamic/modal behavior of the structure using two different optical interrogation schemes to address the same sensor array. The system has been used to monitor over 45 sensors attached to or embedded in a single-lane bridge span, ...
A network of distributed optical Bragg grating sensors is used for monitoring of a full scale laboratory bridge in its pristine and damaged state. Damages consist of a series of cuts that are introduced in an external girder to simulate fracture or fatigue crack of a main load carrying bridge component. The after fracture behavior is described in terms of load path redistribution and strain level changes in the structure. ...
Reports by Author
