长江中下游河道崩岸机理中的河床边界条件

River Boundary Conditions of Mechanism of Bank Failure in Middle and Lower Reaches of Changjiang River

描述了长江中下游河床边界条件对于河道平面变形的影响,介绍了河岸抗冲性分类的研究成果,分析了河岸二元结构对于崩岸影响的2个特点:一是崩岸段河岸断面形态与近岸水流集中冲刷河床相关联;二是根据粘性土层的抗冲性揭示了崩岸过程从量变到质变的间歇性质。

Influences of river boundary conditions on planar channel deformation in the middle and lower reaches of Changjiang River are describeds and research achievements on classification of antiscourability of river bank are introduced in this paper. Two bank-failure characteristics of riverbank with double-layer texture structure are analyzed, namely, the cross-section configuration near river bank for the bank-failure reach is close related to river-bed scouring due to flow concentration in bank area, and the intermittence during the bank-failure process from quantitative change to qualitative change is discovered by the analysis on erosion-resist ing capacity of cohesive clay-layer soil.