都江堰内江河段河床冲淤规律研究

都江堰枢纽区的河床冲淤变化对工程的维护和分流分沙及都江堰灌区的引水和风栖窝的淘淤都具有重要的作用。内江河段进口段的冲淤幅度较大而中下段较小，河床冲淤频繁，淘淤的作用有限。河口河段与水文站河段的冲淤变化为负相关，反映出卵石缓慢运动的滞后影响。水文站河段与卧铁河段的冲淤变化为正相关，内江中下段的挟沙力与输沙量之间基本平衡。河段的冲刷量随综合作用力的增加而加大。1977年的洪水使河口断面的主槽从左变到右而产生滩槽交替，18-1断面为过渡段，以下的五个断面没有明显的冲淤变化，说明该河段的形态基本稳定。本文的研究结果为都江堰水利枢纽的长期安全运行提供了科学依据。

Study on scour and silt of Neijiang river at Dujiangyan

The variation of scour and division of project, the irrigation and silt in Dujiangyan has an essential influence the digging load of Fengqiwo section. The on the maintenance, water-sandvariation of scour and silt at the estuary of Neijiang river is larger than that at the middle and downstream. The river bed has been scoured and silted frequently, while the impact of digging is limited. The variation of scour and silt at the estuary is anti-correlative to that at the hydrology station, it could be attributed to the hysteresis of the gravel motion. The variation of scour and silt at the hydrology station is correlative to that at Wotie section, so that the flow capability is equilibrium with the sediment transport in the middle and downstream of Neijiang river. The scour is greater with the increase of the total effect force of river. The flood in 1977 resulted in the section change of the main channel from left to right. The section 18-1 is transitional, and the following 5 sections has no obvious scour and silt. Thus this river section is basically stable. The research results of this paper provide the scientific support for the long-term safe-running of Dujiangyan project.