Abstract: Bedload transport in natural rivers has strong randomness, and the traditional bedload sampling method can not carry out continuous dynamic monitoring of bedload transport process, which affects the process of research on bedload transport characteristics. In view of the advantages of the acoustic method in the prototype observation of pebble transport, which could be dynamically monitored and had high temporal and spatial resolution, the movement quantity of pebbles was explored by use of the pebble impact signal, combined with the energy variation characteristics of pebble impact audio. The research shows that in the process of single pebble movement, the number of collisions with the bed surface is positively correlated with the flow velocity, but not significantly correlated with the pebble particle size. Based on the test data, an empirical formula for the number of pebble collisions and the flow velocity is established to further calculate the number of pebble movements, which provides a theoretical support for the prototype observation of the acoustic pebble transport.

Key words: waterway engineering; pebble transport; acoustics method; energy change; collision frequency

摘要： 天然河流中的推移质输移具有很强的随机性，传统的推移质采样方法无法对输移过程进行连续的动态监测，限制了对推移质输移特性研究的进程。鉴于声学法在卵石输移原型观测中具有能够动态监测且时空间分辨率高的优势，结合卵石碰撞音频的能量变化特点，探究利用卵石碰撞信号来分析卵石运动数量的方法。研究表明：单颗卵石运动过程中与床面的碰撞次数与水流流速呈正相关、与卵石粒径无较明显的关联；基于试验数据建立卵石碰撞次数与水流流速的经验公式，进一步推算卵石运动数量，为声学法卵石输移原型观测提供一定的理论支撑。

关键词: 航道工程；卵石输移；声学法；能量变化；碰撞次数