黄河下游游荡性河道河势调整关系研究

通过黄河下游游荡性河道典型河段河势观测资料,统计分析了河势的调整关系。研究表明,尽管游荡性河道河势多变不定,但主流线在河宽方向的摆动位置仍有一定的统计规律可循;主流线弦高与弦长之间的调整符合弓形参数间的一般函数关系;随主流线长度增加,弯曲半径不会无限制减小,将会趋于某一相对稳定状态;弯曲系数与主流线长度、弯曲半径之间的统计关系表征了黄河下游游荡性河道河势易出现陡湾且易坐小湾坐陡湾的特性;弯曲半径与河面宽之间具有一定的相关趋势,河面越宽,弯曲半径增加的可能性越大。

Study on the adjustment of river regime at the wandering reach of the lower Yellow River

Based on the observed data in the wandering reach at the lower Yellow River,the adjustment of river regime is analyzed.The results show that the wandering position of the mainstream line in the direction of river width has a statistical rule though the river regime at the wandering reach is inconstant.The regulation between the string height and the string length of the mainstream line accords with a function relationship between the bow parameters.The bending radius reduces with increasing length of the mainstream line,and then tends to be relatively stable.The statistical relationship between the bending coefficient and the length of the mainstream line and bending radius shows that the river regime at the wandering reach of the lower Yellow River has some obvious characteristics,where steep bends are liable to take place and make the bend more wandering.There is a correlation tendency between the bending radius and river width,the wider the river,the more the increasing probability of the bending radius.