Optimization and application of observation systems for elastic wave CT Testing of concrete cut-off walls

Key Points

• This research aims to assess the applicability of different observation systems in detecting internal defects within concrete cut-off walls using elastic wave CT testing.
• Evaluated five distinct observation systems for elastic wave signal processing in concrete.
• Employed shortest ray algorithm and Gauss-Newton methods for image reconstruction.
• Conducted comparative analysis of signal collection, data processing, and image reconstruction performance.
• Fixed observation systems showed superior performance for shallow walls, with localization error under 0.5 m and signal-to-noise ratio over 25 dB.
• Mobile observation systems excelled for deeper walls, with the balanced optimized mobile system recommended for large-area screening.
• Successful identification of local defects in a concrete cut-off wall at a depth of 61 m using the optimized mobile observation system.