Correcting calculation method for suspended sediment runoff of river

Abstract

The invention provides a correcting calculation method for suspended sediment runoff of a river. The correcting calculation method is characterized by comprising the following steps: firstly, calculating average sediment concentration of sections to obtain average value D_CSI and D_CSII of sediment concentrations of two sections; secondly, determining marginal distribution, and calculating joint distribution function parameters: determining marginal distribution functions F1(CSI) and F2(CSII) as well as a parameter theta of a Copula function Ctheta(u, v); thirdly, carrying out interval discrete: equally dividing a value taking interval into n parts, wherein each part h=( D_CSIImax-D_CSIImin) / n, and marking a midpoint of a subinterval [D_CSII(k), D_CSII(k+1)] as xk+1 / 2= xk+h / 2; fourthly, establishing a joint distribution model based on the Copula function; calculating to obtain u= FCSI(xCSI) and v= FCSII(xCSII) as well as an inverse function F<-1>y(v) of y and the Copula function c(u, v) according to given sediment concentrations x_CSI and x_CSII of the sections and the marginal distribution F1(CSI) and F2(CSII); fifthly, correcting the calculated sediment concentration on the basis of conditional expectation. The method has higher applicability; according to the method, the correcting calculation precision of the sediment concentration can be effectively improved, and working intensity of a hydrologic survey is reduced.

Description

Technical field [0001] The invention belongs to the field of hydrological testing, and specifically relates to a method for correcting the amount of suspended sediment transport in a river. [0002] technical background [0003] The sediment in the river can silt the river course, causing the river to overflow and wander. It can also improve the soil and turn the saline-alkali desert into good land. For a river basin or a region, in order to achieve the purpose of benefiting and eliminating harms, it is necessary to understand the characteristics, sources, amounts and temporal and spatial changes of sediment, so as to provide a reliable basis for the development of the river basin and the construction of the national economy. To this end, it is necessary to carry out sediment testing and collect sediment data systematically. [0004] The "River Suspended Load Sediment Test Specification" (GB50159-92) stipulates that for the suspended load sediment transport rate test, the test cont...

AI Technical Summary

Problems solved by technology

[0013] (1) Applicability: The current corrected calculation methods for sediment load mostly focus on the generalized curve formula of vertical distribution of sediment concentration. Influencing factors such as flow velocity and uneven lateral distribution of sediment concentration, the applicability of the generalized vertical line formula is not strong

[0014] (2) The problem of parameter selection: the flow velocity and sediment concentration distribution formulas have a great influence on the correction calculation results. Using the Rouse formula, it is necessary to draw a straight line on the logarithmic grid paper to obtain parameters such as water surface discharge and distribution index

Therefore, the selection process of parameters is cumbersome and often has a large uncertainty.

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