中文摘要：

阶梯-深潭系统是山区河流上一种河床结构形态,具有稳定河床和消能减灾的作用。推移质运动会影响水流结构并改变河床形态,从而影响阶梯-深潭系统的消能效率。在野外构建阶梯-深潭系统,通过人工加沙试验,研究不同来水来沙对阶梯-深潭系统流场及消能的影响。研究表明,推移质运动使阶梯上紊动略增强,深潭中紊动大为减弱,从而使阶梯-深潭系统消能率降低。推移质运动的增强改变水流能量分配,其消能附加作用使阶梯-深潭结构消能降低和深潭淤埋。

英文摘要：

Step-pool system is a typical bed micro-morphology in high gradient mountain rivers, which creates ex- tremely high turbulence intensity and thus dissipates a majority the flow energy. The increase of the bed load transport intensity changed the flow field and reshaped the bedform, thus the energy dissipation effect of the step-pool system changed. A physical model of artificial step-pool system was constructed in a locally regular channel of the upper Wenxia River, a tributary of Han River in the middle Yangtze River. Experiments were conducted to study the flow field and energy dissipation in different flow discharges and bed load transport rates. Experimental results illustrated that the increase of bed load transport intensity significantly changed local flow field in the step and pool. The turbu- lence intensity on the step increased and the turbulence intensity in the pool decreased sharply. The increase of bed load transport intensity leaded to variation of the energy dissipation distribution. The energy dissipated by bed load transport increased, thus the energy dissipation effect of the bed structure of step-pool system decreased and the pool of the step-pool system was filled up.