潼三河段主槽断面间距变化对淤积量的影响

Influence of Variation of Main Channel Section Spacing in Tongguan-Sanmenxia Reach on Sediment Accumulation

潼三河段采用主河槽断面间距和滩间距计算库容和淤积量,受河道形态变化、水库低水位运行和治黄工程修建等影响,原有部分淤积测验断面已经失去控制主河槽的代表性,淤积测验断面间距发生变化,沿用的固定主河槽断面间距影响库容及淤积量的计算精度。分析了潼三河段沿用主河槽断面间距计算淤积量存在的问题,采用断面线中点连接法、断面两侧边线平均法量算主河槽断面间距,并进行淤积量计算,分析断面间距变化对淤积量计算精度的影响,结果表明:在计算模型和方法不变的情况下,只考虑主河槽断面间距因素,用新主河槽断面间距计算出的淤积量较用原间距计算结果均增大,说明一直沿用的主河槽断面间距影响淤积量计算的准确性;河段总间距增大,淤积量也增大,淤积量与断面间距成正比关系。

The main channel section spacing and beach spacing always be used to calculate the storage capacity and silt volume of TongguanSanmenxia reach.The original part of the sedimentation test section has been lost control the representative of the main channel because of the changes in river channel,low water level operation and the construction of river control project for years.Adopted the main channel section spacing affected the accuracy of the storage capacity and sediment calculation as the changes in sedimentation test section spacing.This paper analyzed the problems existing in the main channel section spacing of the Tongguan-Sanmenxia reach.It measured the main channel section spacing through Midpoint connection method and cross section on both sides of the average method and carried out respectively the calculation of sediment volume.It analyzed the effect of section spacing on the accuracy of siltation calculation,improved the accuracy of sedimentation test results.The results show that the calculated deposition amount from the new main channel section spacing is increased comparing with the original spacing in the case of constant calculating model and method and only considers the main channel section spacing factor.It indicates that the accuracy of the calculation of the silt volume is influenced by the followed main channel section spacing.The deposition volume increases as the total spacing of the river increase.The result shows that a positive correlation exists between deposition volume and the distance.