FOR 2825:  Concrete Damage Assessment by Coda Waves (CoDA)

• Subject Area: Construction Engineering and Architecture
• Term: since 2019
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 398216472

Reinforced concrete (RC) structures are an indispensable part of our lives, as our mobility, the industrial performance and the functionality of modern society in general directly depend on the reliability and availability of these structures. Hence, cost-efficient preservation of the integrity of the RC infrastructure over the complete service life is of utmost importance, considering in particular, that modern RC structures have to meet increasing demands with regard to performance. Higher (traffic) loads, longer service life and the use of new materials necessitate a reliable service life prediction method embedded in the framework of a sophisticated management tool. The aim of this project is to develop a novel method for the assessment of the safety and durability of RC structures. The method is based on the application of ultrasonic coda wave interferometry (CWI) to RC structures. Laboratory experiments at the specimen scale (nm - cm range) and structure scale (cm - m) provide correlations between specific types of load (i.e. mechanical or thermal) and their effect on the material as well as features of the coda. Numerical modelling using translation, upscaling and localization methods will be applied to distinguish between different types of load. Finally, methods for using the information from the coda will be developed to enable rapid updates of structural models for service life prediction of RC structures.

• DFG Programme: Research Units

Projects

• Coda wave based ultrasonic methods for concrete - extending the capabilities by using 3d information combination with acoustic emission and exploitation of additional features towards the application on real structures (Applicant Niederleithinger, Ernst )
• Coordination Funds (Applicant Gehlen, Christoph )
• Environmentally/mechanically caused changes in microstructure and their effect on coda signals (Applicant Gehlen, Christoph )
• High-performance simulations of wave propagation for structure analysis of concrete (Applicant Saenger, Erik H. )
• Large scale hybrid models for damage detection in arbitrarily shaped concrete structures (Applicant Wüchner, Roland )
• Scale-bridging Modeling of Microstructural Changes in Concrete and Damage Analysis of Concrete Structures for the Identification of Coda Signals (Applicants Meschke, Günther ;  Timothy, Jithender J. )
• Thermo-mechanical experiments of RC structures correlated to distributed coda signals (Applicant Mark, Peter )

• Spokesperson: Professor Dr.-Ing. Christoph Gehlen