Detecting broken-wire flaws at multiple locations in the same wire of prestressing strands using guided waves

► Three flaws in the same wire can be detected using the low frequency guided wave. ► Only the first flaw is detected using the high frequency guided wave. ► The elastic energy exchange between wires decreases as the frequency increases. ► We observe the recovery length for elastic waves in the prestressing strand. ► A method for distinguishing flaws in different wires or the same wire is provided.