为治理尾闾河道萎缩提供技术支撑,采用实测资料分析与理论探讨相结合的方法,研究了尾闾河道断面形态变化及其与水沙过程的响应关系.结果表明,1986年后,黄河口水沙过程变异,尾闾河道平滩流量和平滩面积大幅度减小,平滩宽深比有所增大,断面形态变的宽浅;2002年后,小浪底水库调水调沙运用,尾闾河道萎缩有所恢复,平滩流量和平滩面积增大,平滩宽深比减小,断面形态朝着窄深方向调整.通过引入水沙过程参数,建立了尾闾河道断面形态与来水量、来沙系数和来水过程等参数的单因素响应关系以及多因素综合关系,在此基础上提出了尾闾河道满足一定输水输沙规模的断面形态所对应的水沙过程临界指标,如当黄河口汛期来水量大于141.2×108m3、汛期来沙系数小于0.03、汛期来水过程参数大于2.3时,利津断面平滩流量可达4000m3/s,相应的平滩面积为1648m2、平滩宽深比为6.3.
For harnessing the atrophy of tail channels,the relationship between the section configuration and flow-sediment was researched using the methods of field data analyses and theoretical study.The results show that,after 1986,with the variation of flow-sediment,the atrophy of tail channels is in evidence,the bank-full area reduce,the width-depth ratio increase,the section configuration become wide and shallow;after 2002,the regulation of flow-sediment of Xiaolangdi Reservoir run successfully,the atrophy of tail channels resume in a certain extent,the bank-full area increase,the width-depth ratio decrease,the section configuration become narrow and deep.Via establishing the relationship between the section configuration and flow-sediment,the critical index of flow-sediment are brought forward.For example,the flood season incoming flow should be bigger than 141.2 billion m3,the flood season incoming sediment coefficient should be less than 0.03,the flood season parameter of flow process should be bigger than 2.3,so the bank-full discharge of Lijin section is 4000m3/s,corresponding bank-full area is 1648m2,width-depth ratio is 6.3.