Large scale hybrid models for damage detection in arbitrarily shaped concrete structures

• Applicant: Professor Dr.-Ing. Kai-Uwe Bletzinger
• Subject Area: Applied Mechanics, Statics and Dynamics ; Architecture, Building and Construction History, Construction Research, Sustainable Building Technology
• Term: since 2019
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 398216472

The work of TUM2 in the first funding period results in a FE-based damage localization methodology. It was shown to work very well for the given dimensions and used frequencies of our benchmarks. Specifically, the following was achieved:- Development of an FE-based damage localization methodology using coda waves.- Development of a formulation for the use of unstructured meshes that allows description of arbitrary geometries- Improvement of the established solution algorithm for the coda damage localization problem by embedding two advanced solution algorithms- Successful application of the novel FE-based methodology to a real experiment. The used frequency of 60kHz represents a novelty in sensitivity-based damage localization with coda waves. It extends the range of usable frequencies into a lower frequency range that is more suitable for application in large structures. The application in real experiments showed very good results, as several closely spaced cracks could be successfully detected and distinguished.Following this path, the goal of the current proposal is to consolidate and specifically develop our methods to.(i) capture the influences of complicated geometries on the coda measurements(ii) identify the parameters of the structural model based on the measured coda wave data. This will be accomplished by further adapting the techniques developed in Phase 1 of this project to meet real-world challenges. (iii) find thresholds for damage detection in the field.(iv) Develop a digital twin that uses all measured data from a structure to identify and quantify characteristic model parameters. The digital twin will also be used to investigate structural mechanical effects on the coda signal.

• DFG Programme: Research Units
• Subproject of: FOR 2825: Concrete Damage Assessment by Coda Waves (CoDA)
• Co-Investigator: Professor Dr.-Ing. Roland Wüchner