Effect of Concrete Compositions in Energy Transmission of Surface Waves for Nondestructive Crack Depth Evaluation

摘要

The amount and magnitude of absorption and scattering of stress waves in concrete, mainly due to internal friction and aggregate inclusions, may be different when concrete mix proportions vary. In this study, we investigate the effect of concrete composition on the measurements of self-calibrated surface wave transmission functions (TRFs) and spectral energy transmission ratios (SETRs) which are used for crack depth estimation in concrete slabs. A series of experiments is carried out on a range of concrete specimens having more realistic crack (not a notch). It is found that the self-calibrated TRFs are very sensitive to both the concrete composition and the crack depth. However, the SETR is less sensitive to the concrete composition and more sensitive to the changes of crack depths. In conclusion the spectral energy transmission method can be effectively used for crack depth estimation in concrete regardless of their material compositions.