黄河下游河道失稳模式分析

立足于黄河下游的几项基本特征，对黄河堤防的失稳模式进行了分析，指出黄河下游河道火稳模式主要有冲决、溃决、震决3种。冲决模式由引起河势变化的诸因素、受体抵御洪水的能力、河势的历史演变等三类要素组成；溃决模式由高水位差、高水力梯度及与此有影响的因素，受体因子、现代曾出现过的不良工程动力地质现象等三类要素组成；震决模式由主动要素、受体不良要素等两类要素组成。按4个层次对3种河道失稳模式进行了分析，建立了由不同地质营力引发的悬河失稳模式。

Analysis on Unstable Patterns of the Lower Yellow River Channel

The paper analyzes unstable patterns of the Yellow River embankments and points out 3 main types of washout, outbreak and break because of earthquake of unstable patterns of the channel in the lower Yellow River based on basic characteristics of the lower Yellow River. The washout mode includes 3 essential factors of various factors that cause the variations of river regime, the capability of against floods and the historical evolution of river regime. The outbreak mode includes 3 type essential factors of high water level, high hydraulic gradient and related factors and bad dynamic geological phenomenon that happened before. The break because of earthquake mode includes 2 type essential factors of initiative and bad quality of the body. It analyzes 3 unstable channel modes based on 4 gradations and establishes an unstable pattern for a suspended river caused by different geological agency.