Non-Destructive Evaluation of Concrete for a Foundation Reuse - The case of existing power switch

ABSTRACT: This presentation describes a comprehensive non-destructive evaluation of existing foundation blocks in a power plant in Ontario, Canada. A two-phase multi-technology condition assessment was performed on three concrete foundations as part of their re-use in the upgrade of the super-structure. The test plan involved preliminary assessment of the adjacent soil to identify the dimensions of footings. Further non-destructive testing was performed on the foundation blocks after partial daylighting of the top part. Ultrasonic Pulse Velocity was used to evaluate the quality, uniformity and structural integrity of concrete. The Sonic-Echo method was used to evaluate the unknown depth of the blocks; Ground Penetrating Radar and Eddy Current methods were used to evaluate the rebar detailing of the foundation blocks. This assessment helped the consultant and the asset owner in making informed decision about re-using these foundation blocks in the rehabilitation and replacement of the superstructure.