强涌潮河口河相关系及其验证

Verification of fluviomorphology for macro-tide estuary with tidal bore

分析并提出了有涌潮的强潮河口的河相关系式,其平均水位下的断面面积可用落潮时的流量(含径流量)和含沙量计算,结果较符合实际情况,但强涌潮河口河宽大、水深浅,仅采用涌潮系数仍有一定的误差,如改用涨潮流量和含沙量,则可大幅减小计算误差.本文还给出了潮汐河口纵向河宽放宽率和面积放大率的定义和计算公式.利用钱塘江河口治理前后50年的实测资料,对130 km长河段的相应断面特征、河宽放宽率、面积放大率以及弯道特征计算式进行了验证,取得了满意的验证结果.

This paper gives some verification results of the fluvial formula for macro-tide estuary with tidal bore. In general, the average cross-section area of an estuary can be calculated by the average ebb tide discharge （including runoff discharge） and the average ebb sediment concentration. The formula is widely used for estuaries and bays. However, as the width and depth of macro-tide estuary with tidal bore is wider and shallower than general estuaries, using coefficient of tidal bore is not enough to offset the inaccuracy. Instead, when using the flood tide discharge and flood sediment concentration, the results are in good agreement with field data. By using the flood and ebb tide discharge distribution around the cross-section, it easily explains the reasons for reduced errors. This paper also gives the definition and calculation formula of the enlargement ratio of width and the enlargement ratio of crosssection area based on the 50-year and 130kin long distance field data observed before and after the regulation of the Qiantang estuary. The paper verifies the relationship among the characteristics of cross-section, the enlargement ratio of width, the enlargement ratio of cross-section area and the characteristics of river curves.