河岸崩塌与稳定分析

Analysis of river bank sloughing and stability

在总结了以往长江河道崩岸问题研究成果的基础上,分析了不同河型河道崩岸的特点及机理,提出了岸坡滑动的计算模式、稳定岸坡的坡降、河道崩岸的预测方法等,在抗滑稳定计算上考虑了河岸动水压力对河岸崩塌的作用;在河岸稳定性判定上,提出了用河道深泓距岸距离和水深确定当前河岸坡度,并与其当前稳定坡度相比较,来判定河岸是否稳定,对于长江中下游,粘土、亚粘土与细沙土夹层河岸的稳定坡度均缓于1∶3.0,各崩岸段深泓离岸距离与平均河宽之比一般为0.07～0.30.

Based on summarizing some former researches on the Yangtze River bank sloughing, the characteristics and mechanisms of the bank sloughing of different river types are analyzed. The calculation mode, slope down of stable bank slope, the predictions of bank sloughing are proposed. The action of the bank dynamic water pressure on the bank sloughing is considered in the calculation of stability (against) sliding .As to the bank stability, a method which use the distance from thalweg in the channel to bank and the water depth to determine the current bank slope is proposed; and through computation with the current stable slope to determine the bank's stability. For the middle and lower reaches of Yangtze River, the stable slope of the bank which consists of clay or light loam soil are all less than 1:3.0, the ratio of the distance from thalweg in the channel to bank and average rive width is 0.07-0.30.