It is necessary to quantify the amount of delamination present in load bearing rock bolts, as small amounts may be deemed acceptable and large amounts may lead to catastrophic failure. In this work, a semi-analytical FEM model is used to calculate the theoretical wave structures for a rod embedded in concrete. A qualitative relationship between percent delamination and wave reflection energy is demonstrated. It is shown that with the proper selection of inspection parameters, it is possible to inspect large lengths (10+ ft.) of embedded rod using an ultrasonic guided wave pulse-echo technique.

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