中文摘要：

在应用冲击波法进行无损估计时，应力波波速测量是一项非常重要的工作。研究了基于高阶谱的时间延迟估计原理及其算法，并将其应用到基于冲击波法的双传感器测量应力波波速方法中，解决了传统的直接观察法中的人为误差的影响和噪声对测量精度的影响，降低了测量误差，波速数据具有更好的一致性，取得了满意的实验结果。

英文摘要：

Measurement of wave speed is very important when impact method is applied to non- destructive testing of concrete structure. Time delay estimation algorithm and theory based on higher order spectrum function are studied. This algorithm has been applied to wave speed evaluation in the case where the wave speed of concrete structures is measured by two transducers. The influences of observation error and noise are eliminated when the higher order spectrum based time delay evaluation is used. Measurement errors are reduced and wave speed data are more consistent. Experiment results are satisfied.