CN113934777B

CN113934777B - Method and system for quantifying influence of backwater jacking on water level change

Info

Publication number: CN113934777B
Application number: CN202111541171.1A
Authority: CN
Inventors: 邓鹏鑫; 邴建平; 张明月; 贾建伟; 徐长江; 徐高洪; 戴明龙; 张冬冬; 程小翠; 王栋; 刘昕; 汪飞; 熊刚; 何康洁; 张馨月; 郭熙望
Original assignee: Hubei Hydrological And Water Resources Emergency Monitoring Center; Bureau of Hydrology Changjiang Water Resources Commission
Current assignee: Hubei Hydrological And Water Resources Emergency Monitoring Center; Bureau of Hydrology Changjiang Water Resources Commission
Priority date: 2021-12-16
Filing date: 2021-12-16
Publication date: 2022-03-04
Anticipated expiration: 2041-12-16
Also published as: CN113934777A

Abstract

The invention provides a method and a system for quantifying the influence of a backwater jacking on water level change, wherein the method comprises the following steps: determining a backwater jacking hydrological simulation model based on historical hydrological data of the target river reach; determining a water level change response characteristic and a contribution rate of the water level change response characteristic to the water level change of the target river reach according to the backwater jacking hydrological simulation model based on the target hydrological data of the target river reach in a target time interval; wherein the water level change response characteristic is a factor affecting the water level change of the target river reach. The influence contribution of the backwater jacking to the water level change can be quantitatively analyzed, and the accuracy of identifying the cause of the high flood level is improved.

Description

Method and system for quantifying influence of backwater jacking on water level change

Technical Field

The invention relates to the technical field of hydrological big data analysis, in particular to a method and a system for quantifying the influence of a backwater jacking on water level change.

Background

In recent years, with the aggravation of climate change and human activity influence, particularly under the interference of human activities such as cascade reservoir group construction, channel improvement, shoreline development and the like, the phenomena of flood river channel atrophy, river flood beach reduction and flood level lifting also occur while the river main channel is cut, the inherent mechanism of the water level flow relation is gradually changed, and the drainage capacity is influenced. Meanwhile, the water level change of the cross section of the downstream river channel can directly change the water surface gradient, particularly in the period of heavy flood, the change is influenced by the backwater jacking, the upstream water level can be traced to the source due to the overhigh water level of the downstream river channel, the flood water level of the river channel under the same flow is raised, and the flood risk is increased.

The current academic world mostly focuses on qualitative analysis of statistical indexes aiming at analysis of influence of backwater jacking on water level change, and can objectively reveal jacking effect of the river and lake, but due to lack of an effective quantitative analysis method, a response mechanism for analyzing backwater jacking from a full quantitative angle is not seen at present, and the method is not thorough in mining of upstream and downstream water power correlation mechanisms of rivers and the river and lake.

Therefore, how to provide a method and a system for quantifying the influence of the backwater top support on the water level change is an urgent problem to be solved, so that the influence contribution of the backwater top support on the water level change is quantitatively analyzed, and the accuracy of identifying the cause of the high flood level is improved.

Disclosure of Invention

Aiming at the defects in the prior art, the embodiment of the invention provides a method and a system for quantifying the influence of a backwater jacking on water level change.

The method for quantifying the influence of the backwater jacking on the water level change is provided, and comprises the following steps:

determining a backwater jacking hydrological simulation model based on historical hydrological data of the target river reach;

determining a water level change response characteristic and a contribution rate of the water level change response characteristic to the water level change of the target river reach according to the backwater jacking hydrological simulation model based on the target hydrological data of the target river reach in a target time interval; wherein the water level change response characteristic is a factor affecting the water level change of the target river reach.

According to the method for quantifying the influence of the backwater jacking on the water level change, which is provided by the invention, the backwater jacking hydrological simulation model is determined based on the historical hydrological data of the target river reach, and the method specifically comprises the following steps:

determining hydrological data of an upstream control section and a downstream control section in a research time period based on historical hydrological data of the target river reach; wherein, the upstream and downstream section hydrological data includes: the upstream control section daily water level data, the upstream control section flow data and the downstream control section daily water level data;

determining a backwater jacking hydrological simulation model based on the hydrological data of the upstream and downstream control sections in the research period; the backwater jacking hydrological simulation model takes an upstream control section water level and a downstream control section water level as input, and takes an upstream control section flow as output.

According to the method for quantifying the influence of the backwater jacking on the water level change, which is provided by the invention, the backwater jacking hydrological simulation model is determined based on the hydrological data of the upstream and downstream control sections of the research time period, and the method specifically comprises the following steps:

determining a calculation formula of a backwater jacking hydrological simulation model based on an open channel constant non-uniform gradual change basic equation;

determining model undetermined parameters of a backwater top support hydrological simulation model calculation formula based on hydrological data of upstream and downstream control sections of the research time period;

the calculation formula of the backwater top-support hydrological simulation model is as follows:

；

in the formula (I), the compound is shown in the specification,

controlling the cross-sectional flow for the upstream;

in order to control the water level of the cross section at the upstream,

controlling the section water level for the downstream;

、

、

and

parameters are to be determined for the model.

According to the method for quantifying the influence of the backwater top support on the water level change, which is provided by the invention, the water level change response characteristic and the contribution rate of the water level change response characteristic to the water level change of the target river section are determined based on the target hydrological data of the target river section in the target time period according to the backwater top support hydrological simulation model, and the method specifically comprises the following steps:

determining water level change response characteristics according to the backwater jacking hydrological simulation model based on target hydrological data of the target river reach at a target time interval; wherein the water level change response characteristic comprises: flow response characteristics, jacking response characteristics, and other factor response characteristics;

determining the contribution rate of the water level change response characteristic to the water level change of the target river reach based on the water level change response characteristic; wherein the contribution rate comprises: flow affecting contribution rate, backwater affecting contribution rate and other affecting contribution rates.

According to the method for quantifying the influence of the backwater jacking on the water level change, which is provided by the invention, the water level change response characteristic is determined according to the backwater jacking hydrological simulation model based on the target hydrological data of the target river reach in the target time period, and the method specifically comprises the following steps:

determining a water level change response characteristic calculation formula based on the backwater jacking hydrological simulation model;

determining the water level change response characteristic according to the water level change response characteristic calculation formula based on the target hydrological data of the target river reach in the target time interval;

wherein the water level variation response characteristic calculation formula includes: a flow response calculation formula, a backwater jacking response calculation formula and other factor response calculation formulas.

According to the method for quantifying the influence of the backwater jacking on the water level change, which is provided by the invention, the model undetermined parameters of the backwater jacking hydrological simulation model calculation formula are determined based on the hydrological data of the upstream and downstream control sections of the research time period, and the method specifically comprises the following steps:

dividing hydrological data of the upstream and downstream control sections of the research time period into model calibration period data and model inspection period data;

determining model undetermined parameters of a calculation formula of the backwater top-supporting hydrological simulation model based on the model calibration data;

determining a backwater top support hydrological simulation model to be detected based on the undetermined parameters of the model;

determining the simulation precision of the backwater top-support hydrological simulation model to be detected according to the model detection period data based on the backwater top-support hydrological simulation model to be detected;

and if the simulation precision meets the preset precision condition, determining that the to-be-detected backwater jacking hydrological simulation model is a target backwater jacking hydrological simulation model.

According to the method for quantifying the influence of the backwater jacking on the water level change, which is provided by the invention, the model undetermined parameters of the backwater jacking hydrological simulation model calculation formula are determined based on the model rate fixed data, and the method specifically comprises the following steps:

training the backwater jacking hydrological simulation model by using the model calibration periodic data;

updating the model undetermined parameters based on a target function, and performing iterative training on the backwater top-support hydrological simulation model based on the updated model undetermined parameters until the backwater top-support hydrological simulation model converges;

wherein the objective function is determined based on a runoff total amount relative error and a certainty coefficient.

The invention also provides a system for quantifying the influence of the backwater jacking on the water level change, which comprises: the hydrological model building unit and the water level change analyzing unit;

the hydrological model building unit is used for determining a backwater jacking hydrological simulation model based on historical hydrological data of a target river reach;

the water level change analysis unit is used for determining a water level change response characteristic and a contribution rate of the water level change response characteristic to the water level change of the target river reach according to the backwater roof support hydrological simulation model based on target hydrological data of the target river reach in a target time period; wherein the water level change response characteristic is a factor affecting the water level change of the target river reach.

The invention also provides an electronic device, which comprises a memory, a processor and a computer program which is stored on the memory and can run on the processor, wherein when the processor executes the program, the steps of any one of the above quantitative methods for the influence of the backwater jacking on the water level change are realized.

The present invention also provides a non-transitory computer readable storage medium having stored thereon a computer program which, when executed by a processor, performs the steps of any of the methods for quantifying the effect of backwater jacking on water level variations as described above.

According to the method and the system for quantifying the influence of the backwater jacking on the water level change, provided by the invention, the backwater jacking hydrological simulation model is determined to carry out analog reproduction on the river channel water level change process by analyzing the historical hydrological data of the target river reach. On the basis, the contribution rate of the water level change response characteristics and the contribution rate of the water level change response characteristics to the water level change of the target river reach are calculated, the quantitative analysis of the influence contribution of the backwater jacking to the water level change is realized, and the accuracy of identifying the cause of the high flood level is effectively improved.

Drawings

In order to more clearly illustrate the technical solutions of the present invention or the prior art, the drawings needed for the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and those skilled in the art can also obtain other drawings according to the drawings without creative efforts.

FIG. 1 is a flow chart of a method for quantifying the influence of a backwater jacking on water level variation according to the present invention;

FIG. 2 is a schematic flow chart of a method for quantifying the influence of a backwater jacking on water level variation according to the present invention;

FIG. 3 is a schematic diagram showing comparison between measured daily average flow and simulated average flow of section a in 2008-2020;

FIG. 4 is a schematic view of a scattering point associated with a measured daily average flow and a simulated daily average flow in 2008-2020 of section a provided by the present invention;

FIG. 5 is a schematic diagram showing comparison between measured daily average water level and analog value of section a in 2008-2020;

FIG. 6 is a schematic view of a scattering point associated with a measured daily average water level and an analog value in section a of 2008-2020;

FIG. 7 is a graph showing the variation of the contribution rate of the N lake backwater jacking on the water level of the section a;

FIG. 8 is a box diagram of the contribution rate of the factors on the water level of the section a provided by the present invention;

FIG. 9 is a schematic view of a quantitative system structure of the influence of a backwater jacking on water level variation according to the present invention;

fig. 10 is a schematic physical structure diagram of an electronic device provided in the present invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention clearer, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings, and it is obvious that the described embodiments are some, but not all embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

The phenomenon that the upstream water level is choked up due to the influence of downstream backwater is called backwater jacking in the hydrological analysis field. Generally, under the same flow condition, the higher the backwater jacking strength is, the higher the upstream water level is choked up.

Therefore, the quantitative evaluation of the influence of the backwater top support on the water level change is a premise and a basis for deeply developing flood control and disaster reduction work in a drainage basin, and the quantitative evaluation of the strength influence of the top support is very important for identifying the cause of the high flood water level. How to further accurately quantify the influence of backwater jacking is one of the problems to be solved urgently in the field of hydrological analysis and is also a difficult problem faced in the basin flood control practice.

Fig. 1 is a flowchart of a method for quantifying an influence of a backwater jacking on a water level change, as shown in fig. 1, an embodiment of the present invention provides a method for quantifying an influence of a backwater jacking on a water level change, including:

step S1, determining a backwater jacking hydrological simulation model based on historical hydrological data of the target river reach;

step S2, determining a water level change response characteristic and a contribution rate of the water level change response characteristic to the water level change of the target river reach according to the backwater top support hydrological simulation model based on the target hydrological data of the target river reach in a target time period; wherein the water level change response characteristic is a factor affecting the water level change of the target river reach.

Specifically, before performing the water level variation analysis, a research object corresponding to the water level variation, that is, a target river reach needs to be determined. And selecting a period of time as a research period, marking as T, and taking hydrological data corresponding to the target river reach in the research period as historical research data according to research requirements (river reach characteristics, flood control requirements and the like) and the integrity degree of the data.

In step S1, mining and analyzing the Hydrological data based on the historical Hydrological data of the target river reach, simulating the water level variation process of the target river reach, and determining a backwater top supporting Hydrological simulation model (a Hydrological model understanding backing water jack model, which is abbreviated as an HMCBJ model) in consideration of the backwater top supporting Hydrological model.

It should be noted that, the specific expression formula of the backwater top-support hydrological simulation model, the type and number of parameter data included in the formula, and the specific methods of the model and training can be selected and adaptively adjusted according to the actual situation, which is not limited in the present invention.

It can be understood that the constructed backwater jacking hydrological simulation model can effectively reflect the water level change process of the target river reach in the research period. When quantitative analysis of water level change in a specific certain time period is carried out, the time period is selected as a target time period, and target hydrological data of the target time period is used as the basis of water level change analysis.

In step S2, based on the target hydrological data of the target river reach at the target time interval, a factor that the water level variation response characteristic represents to affect the water level variation of the target river reach is determined according to the backwater jacking hydrological simulation model. And calculating the contribution rate of different water level change response characteristics to the water level change of the target river reach.

It should be noted that, in the present invention, one or more factors affecting the water level change of the target river reach may be provided, and the specific type and number of the affecting factors may be set according to the actual situation, and corresponding to the affecting factors, the contribution rates corresponding to different factors may also be adaptively adjusted, which is not limited in the present invention.

According to the method for quantifying the influence of the backwater jacking on the water level change, provided by the invention, the backwater jacking hydrological simulation model is determined to carry out analog reproduction on the river channel water level change process by analyzing the historical hydrological data of the target river reach. On the basis, the water level change response characteristics and the contribution rate of the water level change response characteristics to the water level change of the target river reach are calculated, the quantitative analysis of the influence contribution of the backwater jacking to the water level change is realized, and the accuracy of identifying the cause of the high flood level is effectively improved.

Optionally, according to the method for quantifying the influence of the backwater jacking on the water level change, the method for determining the backwater jacking hydrological simulation model based on the historical hydrological data of the target river reach specifically includes:

Specifically, the method starts from the multi-linear water level flow relation and quantitatively analyzes the influence of the backwater jacking on the water level change. Selecting a target river reach according to distribution of a drainage basin water system and a lake, determining an upstream and downstream control section, and recording the upstream control section as

Downstream control section, note

The downstream control section is preferably capable of characterizing a downstream river or lake jacking affected section.

Determining a backwater top support hydrological simulation model based on historical hydrological data of a target river reach, and specifically comprising the following steps:

and collecting basic hydrological data of each section in the research period based on historical hydrological data of the target river reach, determining the hydrological data of upstream and downstream control sections in the research period, and constructing a basic analysis database by using the hydrological data of the upstream and downstream control sections.

Wherein, the upstream and downstream section hydrological data includes: the upstream control section daily water level data, the upstream control section flow data and the downstream control section daily water level data.

And determining a backwater jacking hydrological simulation model by taking the upstream control section water level and the downstream control section water level as model inputs and taking the upstream control section flow as model output based on the upstream and downstream control section hydrological data in the research period and combining a computer big data mining technology.

The method for quantifying the influence of the backwater jacking on the water level change analyzes historical hydrological data of a target river reach by a computer big data mining technology, takes an upstream control section water level and a downstream control section water level as model input, takes an upstream control section flow as model output, and determines a backwater jacking hydrological simulation model. The influence of the upstream and downstream control sections on the water level change can be accurately reflected, the quantitative analysis of the influence factors of the backwater jacking is realized, and the technical support can be better provided for flood control and disaster reduction in the drainage basin.

Optionally, according to the method for quantifying the influence of the backwater jacking on the water level change, the determining of the backwater jacking hydrological simulation model based on the hydrological data of the upstream and downstream control sections of the research time period specifically includes:

；

in the formula (I), the compound is shown in the specification,

controlling the cross-sectional flow for the upstream;

in order to control the water level of the cross section at the upstream,

controlling the section water level for the downstream;

、

、

and

parameters are to be determined for the model.

Specifically, based on study period upstream and downstream control section hydrological data, confirm return water top support hydrological simulation model, specifically include:

(1)

in the formula (I), the compound is shown in the specification,Q _n、Q _refrespectively a flow to be solved under a specific water level and a certain reference datum flow; deltaZ _n、△Z _refIs prepared by reacting withQ _n、Q _refThe corresponding fall is obtained from the water levels of the upstream and the downstream at the same time;canddare model parameters.

In the formula (1), the reference flow and various auxiliary curves are required to be calculated, the calculation is complicated, and the water level is difficult to be calculated through the flow on an irregular river channel. Aiming at the defect, introducing an open channel constant non-uniform gradient flow basic equation, replacing an energy slope with water surface gradient, coupling the nonlinear relation between river width and water depth, reconstructing the formula (1), and deriving to obtain a relation formula (2):

(2) in the formula (I), the compound is shown in the specification,

in order to thanks to the factor of competence,

，

in order to obtain a coarse ratio,

the average water depth of the section;

is the area of the flow cross section;

is the average water depth of the reference section; z is the water level.

The formula (2) is obtained on the basis of assuming that the river reach water flow is an open channel constant gradual flow. If the research river reach is too long, the constant assumption of the open channel is not met, and therefore the simulation precision is influenced. But considering that the shorter the length of the river segment, the closer the river current characteristics will be to the constant flow of the open channel. Based on the condition, the total length of the target river reach is set as

Is divided into

And (3) each section of water flow condition satisfies the relation of the formula (2), and the following steps are provided:

(3) in the formula:

=1, 2, 3…

,

is the total number of stages.

There is an approximate "normal flow" condition in the river on average, under which

For a fixed value, the water level and flow can be calculated by a single-value water level and flow relation formula, namely:

(4) in the formula:

is a specific section parameter;

、

is a specific parameter.

By substituting formula (4) for formula (3), on average within each segment

For constant value, by symbols

And (4) showing. And meanwhile, the right formula is subjected to approximate equivalence treatment, and the formula (4) can be converted into:

(5) in the formula:

and

are parameters to be determined.

Order to

Is composed of

Further transforming equation (5) to obtain:

(6) in the formula (I), the compound is shown in the specification,

controlling the cross-sectional flow for the upstream;

in order to control the water level of the cross section at the upstream,

controlling the water level of the section (or the water level of a lake outlet or a lake region communicated with a river or a lake) for the downstream, and representing a backwater jacking control factor;

、

、

and

parameters are determined for the model, wherein

Is a specific parameter reflecting the characteristics of the upstream profile.

It should be noted that the formula (6) is a calculation formula of the backwater jacking hydrological simulation model obtained through derivation, can be regarded as an empirical calculation formula, and can be used for calculating the flow rate only by taking the river reach water level as input, so that the structure is simple and the calculation is convenient.

Because the derivation is carried out on the premise of an open channel constant gradual flow equation, the model parameters

、

And

the characteristics of river reach topography, roughness and the like are reflected on the whole, and certain physical basis is hidden. In addition to this, the present invention is,

the average water level of the cross section when the flow is 0 can be visually regarded, and the river bed elevation near the cross section is reflected.

After the model calculation formula (6) is determined, based on the hydrological data of the upstream and downstream control sections in the research period, the undetermined parameters of the model of the backwater jacking hydrological simulation model calculation formula are obtained by jointly calibrating and obtaining the long-series water level and flow data of the upstream and downstream sections in the river reach

、

、

And

and determining a target backwater top-support hydrological simulation model.

It will be appreciated that after the target return water jacking hydrological simulation model is determined, a third quantity may be determined by simulation knowing any two of the upstream control profile flow, the upstream control profile water level, and the downstream control profile water level. For example: the water level and flow of the upstream target section are used as simulation indexes, and the water level of the downstream control section is used as a backwater influence control index (the water level and flow of the upstream target section are known, and the water level of the downstream control section is obtained).

According to the method for quantifying the influence of the backwater jacking on the water level change, provided by the invention, the historical hydrological data of the target river reach is subjected to deep data mining, the hydraulic relationship between the upstream and the downstream of the target river reach is associated, a hydrological simulation model considering the influence of the backwater jacking is deduced and constructed, and the simulation and reproduction of the river course water level change process are realized. And this scheme only needs use historical hydrology data alright confirm hydrology simulation model, satisfies under the prerequisite of model accuracy, guarantees that model structure is simple and easily promote, has stronger realistic meaning, can extensively be applicable to each different river reach to satisfy drainage basin flood control management demand.

Optionally, according to the method for quantifying the influence of the backwater roof support on the water level change provided by the present invention, the method for determining the response characteristic of the water level change and the contribution rate of the response characteristic of the water level change to the water level change of the target river section based on the target hydrologic data of the target river section in the target time period according to the backwater roof support hydrologic simulation model specifically includes:

Specifically, the obtained backwater jacking hydrological simulation model is analyzed, and factors influencing the water level change of the target river reach are divided into three categories, namely, the water level change response characteristics comprise: the flow response characteristics, the jacking response characteristics and the other factor response characteristics correspond to contribution rates which are respectively flow influence contribution rates, backwater influence contribution rates and other influence contribution rates.

Based on target hydrological data of the target river reach in a target time period, determining the contribution rate of the water level change response characteristic and the water level change response characteristic to the water level change of the target river reach according to a backwater jacking hydrological simulation model, and specifically comprising the following steps of:

and respectively calculating to obtain flow response characteristics, jacking response characteristics and other factor response characteristics according to the backwater jacking hydrological simulation model based on the target hydrological data of the target river reach in the target time period.

And based on calculationThe obtained water level change response characteristics determine the comprehensive influence value of the water level change response characteristics on the water level change

And further calculating the contribution rate of the water level change response characteristics to the water level change of the target river reach.

It can be understood that the water level variation response characteristic has a comprehensive influence value on the water level variation

Is the sum of the absolute values of the flow response characteristic, the jacking response characteristic and the response characteristic of other factors.

The aggregate impact contribution is defined as:

(7) in the formula (I), the compound is shown in the specification,

influencing contribution rate for flow;

influence contribution rate for backwater;

contribution rate to other influences;

the integrated impact value is represented.

Further, it can be understood that after the contribution rate of the water level change response characteristics to the water level change of the target river reach is determined, a response characteristic curve can be drawn, and then the influence contribution of the backwater top support to the water level change can be intuitively and quantitatively analyzed.

According to the method for quantifying the influence of the backwater jacking on the water level change, provided by the invention, the backwater jacking hydrological simulation model is determined to carry out analog reproduction on the river channel water level change process by analyzing the historical hydrological data of the target river reach. On the basis, the water level change response characteristics and the contribution rate of the water level change response characteristics to the water level change of the target river reach are calculated, the influence of river reach incoming water, a backwater top support and other influence factors can be more practically and accurately quantitatively represented, the relative contribution of each influence factor to the high flood level can be quantitatively analyzed, the accuracy of identifying the cause of the high flood level is effectively improved, technical support is provided for judging the cause of the high flood level in a drainage basin, and an effective scheme decision basis is provided for flood control treatment of the target river reach in practical application.

Optionally, according to the method for quantifying the influence of the backwater jacking on the water level change provided by the present invention, the determining the response characteristic of the water level change according to the backwater jacking hydrological simulation model based on the target hydrological data of the target river reach at the target time interval specifically includes:

Specifically, based on target hydrological data of a target river reach at a target time interval, determining water level change response characteristics according to a backwater jacking hydrological simulation model, and specifically comprising:

and determining a water level change response characteristic calculation formula based on the backwater top support hydrological simulation model. The water level variation response characteristic calculation formula comprises: a flow response calculation formula, a backwater jacking response calculation formula and other factor response calculation formulas.

It can be understood that, in order to better reflect the characteristics of the river reach in the target time interval, a comparative reference period, denoted as TJ, of the target river reach is determined according to the hydromechanical characteristics of the river reach. Since the river reach hydrological relations under the annual average condition are generally considered to be approximately balanced, the comparison benchmark period is preferably the average condition of multiple years in the research period (target period), and the average condition is taken as the comparison benchmark to reflect the daily situation of the river reach water flow conditions.

For example: historical hydrological data used for constructing a backwater top-support hydrological simulation model are data in 2008-2020, a research period T is 6 months and 1 day-30 days, and corresponding target hydrological data are hydrological data in 2008-2020 and 6 months and 1 day-30 days. The comparison reference period corresponding data is data of 6 months, 1 days and 30 days under the average condition of years in 2008-2020.

For the river section affected by backwater, according to the backwater jacking hydrological simulation model, the relation of the water level and the flow can be recorded as

. Is obviously when

In the case of a constant value, the value of,

change only with flow

And the corresponding water level and flow relation is a stable single-value type relation.

Under this condition, assume that

Without change, the flow response can be expressed as:

(8) in the formula (I), the compound is shown in the specification,

representing a flow variation value;

indicating an upstream target interruption caused by a flow change at a certain downstream control section levelThe change of the surface water level, namely the flow change response;

to compare the baseline period water levels.

If the target section water level at the upstream side changes due to the downstream control section water level changes under the condition of constant flow, the response of the downstream backwater jacking can be considered. The larger the amplitude of the water level variation caused is, the stronger the response intensity of the backwater jacking is, and the backwater jacking response can be expressed as:

(9) in the formula (I), the compound is shown in the specification,

representing a downstream water level change value;

when the flow is constant, the water level change of the upstream control section caused by the water level change of the downstream control section is represented, namely the backwater jacking response;

to compare the baseline period water levels.

Because the developed hydrological simulation model only considers the influence of inlet flow and downstream backwater and ignores other influence factors such as interval confluence, river-following drainage and the like, the simulated water level of the hydrological simulation model is deviated from the actual water level and is mainly influenced by other factors, and the response of other factors is recorded as

It can be defined as:

(10) in the formula (I), the compound is shown in the specification,

as a backwater roofThe water level value of the upstream control section simulated by the water-supported hydrological simulation model,

actually measuring a water level value for an upstream control section;

to compare the baseline period water levels.

And respectively calculating to obtain different water level change response characteristics according to the water level change response characteristic calculation formula based on the target hydrological data of the target river reach in the target time period.

Optionally, according to the method for quantifying the influence of the backwater top support on the water level change, the method for determining the model undetermined parameter of the backwater top support hydrological simulation model calculation formula based on the hydrological data of the upstream and downstream control sections of the research time period specifically includes:

Specifically, based on the hydrological data of the upstream and downstream control sections in the research period, the model undetermined parameters of the calculation formula of the backwater jacking hydrological simulation model are determined, and the method specifically comprises the following steps:

and dividing hydrological data of the upstream and downstream control sections in the research period into model rate periodic data and model inspection period data, optimizing model parameters by using a big data mining technology in the rate periodic period, and developing model precision inspection in the inspection period.

It will be appreciated that the model rates are periodic

Data and model inspection period

The division method of the material may be based on the analysis data length. For example: when the data length is

Time, rate is scheduled

In

Is taken as

In the inspection period

In

Is taken as

. In addition, time division, random division, and the like can be used, which is not limited in the present invention.

And determining model undetermined parameters of a backwater top-support hydrological simulation model calculation formula based on the model calibration data, substituting the acquired model undetermined parameters into the model calculation formula, and determining the backwater top-support hydrological simulation model to be detected.

And determining the simulation precision of the backwater top-supporting hydrological simulation model to be detected according to the model detection period data based on the backwater top-supporting hydrological simulation model to be detected.

It can be understood that on the basis of the determination of parameters of the backwater top support hydrological simulation model, the section water level is controlled from the upstream of the river reach

And downstream control of cross-sectional water level

Can directly simulate the upstream control section flow in the river reach inspection period and is recorded as

. Similarly, the cross-sectional flow is controlled from the upstream of the river course

And downstream control of section level

Or according to a backwater top-supporting hydrological simulation model, simulating the water level of an upstream target section in the inspection period through the model, and recording the water level as

. The simulation accuracy of the model can be determined according to the difference between the measured value and the model simulation value.

And if the simulation precision meets the preset precision condition, determining that the backwater top-support hydrological simulation model to be detected is the target backwater top-support hydrological simulation model. Otherwise, the accuracy of the to-be-detected backwater top support hydrological simulation model is considered to be insufficient, and undetermined parameters of the model are determined again.

For example: the simulation accuracy of the index expression (11) model is evaluated in accuracy.

(11)

In the formula (I), the compound is shown in the specification,

、

representing a deterministic coefficient;

、

representing the gross balance error;

、

or

、

Respectively represent

Time interval flow or water level observed value and model analog value;

is as follows

An average of the time-interval flow observations;

、

respectively represent

Average value of the time interval water level observation value and the model simulation value;

is the data length.

Setting the preset precision condition asDCHas a value range of more than 0.9, andREis less than 5%. And when the condition is met, determining that the simulation precision reaches the optimum, and determining that the backwater jacking hydrological simulation model to be detected is the target backwater jacking hydrological simulation model.

The method for calculating the simulation accuracy and the predetermined accuracy condition are only described as a specific example. In addition, in the practical application process of the present invention, the method for determining the simulation accuracy of the model according to the measured value and the simulated value may be set according to the practical situation, and correspondingly, the preset accuracy condition may also be set according to the practical situation, which is not limited in the present invention.

The method for quantifying the influence of the backwater jacking on the water level change analyzes historical hydrological data of a target river reach, constructs a hydrological simulation model considering the influence of the backwater jacking on the basis of fully training and memorizing hydrological change characteristics by combining a computer big data mining technology, and simulates and reproduces the hydrological change process of a river channel. And by means of a method of dividing data into a rate period and a test period, after undetermined parameters of the model are determined, the simulation precision of the model is detected, the accuracy of the model can be effectively improved, and the accuracy of a quantitative result of the influence of the backwater jacking on the water level change is further ensured.

Optionally, according to the method for quantifying the influence of the backwater top support on the water level change, the method for determining the model undetermined parameter of the backwater top support hydrological simulation model calculation formula based on the model rate timing data specifically includes:

Specifically, based on the model rate periodic data, the model undetermined parameters of the calculation formula of the backwater top support hydrological simulation model are determined, and the method specifically comprises the following steps:

using the model rate periodic data to rate the upstream target cross-sectional flow of the periodic river reachQAiming at the target, a backwater top-support hydrological simulation model is trained by relying on a basic analysis database.

Updating model undetermined parameters based on the target function, performing iterative training on the backwater top support hydrological simulation model based on the updated model undetermined parameters until the backwater top support hydrological simulation model is converged, and determining an optimal model

、

、

And

and the like.

Wherein the objective functionIs determined based on the relative error of the total runoff amount and a certainty coefficient. Relative error of total runoff amountREThe difference between the absolute value of the (relative error) and the deterministic coefficient dc (deterministic coefficient) is at least the objective function.

The objective function is defined as:

(12) in the formula (I), the compound is shown in the specification,DCrepresenting a deterministic coefficient;RErepresenting the gross balance error;

、

is shown as

A time-interval flow observed value and a model simulation value;

is as follows

An average of the time-interval flow observations;

is the data length.

It can be understood that the method for training the model of the present invention may be a method using a big data mining optimization technology, such as a global optimization algorithm SCE-ua (short complex evolution University of arizona), a particle swarm algorithm, an ant colony algorithm, an artificial bee colony algorithm, etc., and the specific training method may be set according to the actual situation, which is not limited in the present invention.

According to the method for quantifying the influence of the backwater jacking on the water level change, provided by the invention, the backwater jacking hydrological simulation model is determined to carry out analog reproduction on the river channel water level change process by analyzing the historical hydrological data of the target river reach. The model is trained by dividing data into rate period data and inspection period data, model parameters are determined after the model is converged, and model simulation precision inspection is performed through the inspection period data, so that the accuracy of the model can be effectively improved, and the accuracy of a quantitative result of the influence of the backwater jacking on the water level change is further ensured.

Fig. 2 is a schematic flow chart of a method for quantifying the influence of a backwater jacking on water level variation provided by the present invention, and as shown in fig. 2, the method for quantifying the influence of a backwater jacking on water level variation provided by the present invention is described with reference to specific examples:

according to the water system and N lake distribution of the M river basin, the section from the middle river A city to the middle river B city river section of the M river basin is taken as a target river section, the section a of the middle river A city river section of the upstream river A city is taken as an upstream control section and is marked as

(ii) a The star section of the downstream N lake entering the river channel is taken as a downstream control section and is recorded as

。

According to hydrological data of the section of the city A and the section of the star, considering that the midstream river reach of the M river gradually enters a relative stable period under the influence of the hydrological engineering since 2008, determining the research period as 2008-2020, and recording as T.

And taking the average water level and flow process of the section a and the section star as comparison benchmark periods in 2008-2020 years. And the water level and the flow of the section a are used as simulation indexes, and the water level of the star section is used as an influence control index of the N lake backwater.

And collecting basic hydrological data of each section in a research period, wherein the basic hydrological data comprise water level and flow data of the upstream a section every day in 2008-2020 and water level data of the downstream control section every day in 2008-2020, and constructing a basic analysis database.

When a hydrological process simulation model of the city A considering N lake backwater is constructed by utilizing a basic analysis database, analysis data are divided into a periodic period and a test period according to the length, model parameters are optimized by utilizing a big data mining technology in the periodic period, and the precision test of the model is developed in the test period.

The research time period is 2008-2020, and the length of the data seriesn=4749, get

（i3166) is a rate period,

（j=3166,3167.., 4749) is the check period.

To rate the upstream target section flow of the river reachQAiming at the problem, an HMCBJ model is established by taking the daily average water level of the section a and the section star as input according to a basic analysis database, and the relative error of the total runoff quantity is taken asREThe minimum difference between the absolute value of the (relative error) and the deterministic coefficient dc (deterministic coefficient) is an objective function, and the model parameters are determined.

And (3) evaluating the simulation precision of the index expression (11) model with precision on the basis of HMCBJ model parameter determination. The model parameter optimization results and the hydrological process simulation accuracy indexes are shown in table 1.

Fig. 3 is a schematic diagram showing comparison between an actual measured daily average flow rate and a simulated value in 2008-2020 of a section a provided by the present invention, fig. 4 is a schematic diagram showing correlation between an actual measured daily average flow rate and a simulated value in 2008-2020 of a section a provided by the present invention, fig. 5 is a schematic diagram showing comparison between an actual measured daily average water level and a simulated value in 2008-2020 of a section a provided by the present invention, fig. 6 is a schematic diagram showing correlation between an actual measured daily average water level and a simulated value in 2008-2020 of a section a provided by the present invention, and simulation and actual measurement comparison are shown in fig. 3-6.

As can be seen from Table 1, the certainty factor of each target element is greater than 0.90, and the absolute value of the total balance error is less than 1%, at this time, the simulation effect is excellent, and the data simulation precision is high.

Table 1 model parameter optimization results and hydrological process simulation precision indexes

Therefore, at the moment, the simulation precision of the HMCBJ model meets the preset precision condition, and the HMCBJ model is used as the target HMCBJ model.

On the basis of selecting a typical annual flood process, a target HMCBJ model is used for reproducing the water level and flow change of a river reach, a response characteristic index and an influence contribution rate relative to a reference period are calculated, and the influence of backwater jacking is quantified.

Selecting the synchronous flood process of upstream and downstream sections of the typical year as an analysis object and recording the analysis object as an analysis objectYThe flood period is recorded ast(target period). For example: selecting a flood process from 28 days in 6 months to 18 days in 8 months in 2020 as an analysis object, wherein the typical year is 2020, and the flood time period is from 28 days in 6 months to 18 days in 8 months.

Calculating flood time periodstThe process of the average water level and the flow of the inner upstream and downstream control sections for many years is used as a flood process of a comparative benchmark period and is recorded as

. For example: and calculating the average value of the water level of the city A, the flow and the star water level in the year 2008-2020 in the flood time period of 28 days in 6 months to 18 days in 8 months as a flood process in the comparative benchmark period.

And simulating the water level change process from 6 month, 28 days to 8 month, 18 days in 2020 by using a target HMCBJ model, calculating flow response, jacking response and other factor response values relative to a reference period day by using a response characteristic index and an influence contribution rate calculation formula, calculating corresponding influence contribution rates, and selecting characteristic water level conditions to perform quantitative evaluation on the jacking of the N lake backwater. The specific evaluation results are shown in Table 2.

TABLE 2 evaluation results of N-lake backwater jacking under characteristic water level flow

As shown in table 2, under the flood condition of 2020, the average contribution rate of the N-lake backwater to the water level change of the city a is 36.1%, the contribution rate of the M-river incoming water is 58.1%, and the contribution rate of other factors is 5.8%. When the maximum daily average flow of the city A is reached, the water level change is mainly influenced by the top support of the incoming water and the return water of the M river, and the contribution rates are respectively 61.9 percent and 37.9 percent; when the highest daily average water level exists in the city A, the water level change is also influenced by other factors, wherein the contribution rate of the N lake backwater jacking is 43.7%, the contribution rate of the M river incoming water is 51.1%, and the contribution rate of the other factors is 5.2%.

FIG. 7 is a graph showing the variation of the contribution rate of the N lake backwater jacking on the water level of the section a, and FIG. 8 is a box diagram showing the contribution rate of the factors on the water level of the section a. The N lake backwater jacking influence contribution rate change curve and the comprehensive influence contribution rate box chart of all factors are shown in FIGS. 7 and 8.

The method for quantifying the influence of the backwater jacking on the water level change is only used as an example to describe the invention, and is not used for limiting the invention.

Fig. 9 is a schematic structural view of a system for quantifying the influence of a backwater top support on water level variation, as shown in fig. 9, the invention further provides a system for quantifying the influence of a backwater top support on water level variation, including: a hydrological model building unit 910 and a water level variation analyzing unit 920;

the hydrological model building unit 910 is configured to determine a backwater jacking hydrological simulation model based on historical hydrological data of the target river reach;

the water level change analysis unit 920 is configured to determine a water level change response characteristic and a contribution rate of the water level change response characteristic to the water level change of the target river reach according to the backwater roof support hydrological simulation model based on target hydrological data of the target river reach at a target time interval; wherein the water level change response characteristic is a factor affecting the water level change of the target river reach.

The Hydrological model building unit 910 is configured to mine and analyze Hydrological data based on historical Hydrological data of the target river reach, simulate a water level change process of the target river reach, and determine a backwater jacking Hydrological simulation model (a Hydrological model understanding backing water jack model, which is referred to as an HMCBJ model for short) in consideration of a backwater jacking.

And the water level change analysis unit 920 is configured to determine, based on the target hydrological data of the target river reach at the target time interval, a factor that the response characteristic of the water level change indicates to affect the water level change of the target river reach according to the backwater jacking hydrological simulation model. And calculating the contribution rate of different water level change response characteristics to the water level change of the target river reach.

According to the system for quantifying the influence of the backwater jacking on the water level change, provided by the invention, the backwater jacking hydrological simulation model is determined to carry out analog reproduction on the river channel water level change process by analyzing the historical hydrological data of the target river reach. On the basis, the water level change response characteristics and the contribution rate of the water level change response characteristics to the water level change of the target river reach are calculated, the quantitative analysis of the influence contribution of the backwater jacking to the water level change is realized, and the accuracy of identifying the cause of the high flood level is effectively improved.

It should be noted that, the system for quantifying the influence of the backwater top support on the water level change provided by the present invention is used for executing the method for quantifying the influence of the backwater top support on the water level change, and the specific implementation manner is consistent with the method implementation manner, and is not described herein again.

Fig. 10 is a schematic physical structure diagram of an electronic device provided in the present invention, and as shown in fig. 10, the electronic device may include: a processor (processor)101, a communication interface (communication interface)102, a memory (memory)103 and a communication bus 104, wherein the processor 101, the communication interface 102 and the memory 103 complete communication with each other through the communication bus 104. The processor 101 may invoke logic instructions in the memory 103 to perform a method of quantifying the effect of backwater jacking on water level changes, the method comprising: determining a backwater jacking hydrological simulation model based on historical hydrological data of the target river reach; determining a water level change response characteristic and a contribution rate of the water level change response characteristic to the water level change of the target river reach according to the backwater jacking hydrological simulation model based on the target hydrological data of the target river reach in a target time interval; wherein the water level change response characteristic is a factor affecting the water level change of the target river reach.

In addition, the logic instructions in the memory 103 may be implemented in the form of software functional units and stored in a computer readable storage medium when the logic instructions are sold or used as independent products. Based on such understanding, the technical solution of the present invention may be embodied in the form of a software product, which is stored in a storage medium and includes instructions for causing a computer device (which may be a personal computer, a server, or a network device) to execute all or part of the steps of the method according to the embodiments of the present invention. And the aforementioned storage medium includes: various media capable of storing program codes, such as a usb disk, a removable hard disk, a Read-only memory (ROM), a Random Access Memory (RAM), a magnetic disk, or an optical disk.

In another aspect, the present invention also provides a computer program product comprising a computer program stored on a non-transitory computer readable storage medium, the computer program comprising program instructions which, when executed by a computer, enable the computer to perform a method for quantifying the effect of a backwater jacking on a water level change, the method comprising: determining a backwater jacking hydrological simulation model based on historical hydrological data of the target river reach; determining a water level change response characteristic and a contribution rate of the water level change response characteristic to the water level change of the target river reach according to the backwater jacking hydrological simulation model based on the target hydrological data of the target river reach in a target time interval; wherein the water level change response characteristic is a factor affecting the water level change of the target river reach.

In yet another aspect, the present invention also provides a non-transitory computer readable storage medium having stored thereon a computer program which when executed by a processor is implemented to perform the method for quantifying the effect of the provided backwater jacking on water level variation, the method comprising: determining a backwater jacking hydrological simulation model based on historical hydrological data of the target river reach; determining a water level change response characteristic and a contribution rate of the water level change response characteristic to the water level change of the target river reach according to the backwater jacking hydrological simulation model based on the target hydrological data of the target river reach in a target time interval; wherein the water level change response characteristic is a factor affecting the water level change of the target river reach.

The above-described embodiments of the apparatus are merely illustrative, and the units described as separate parts may or may not be physically separate, and the parts displayed as units may or may not be physical units, may be located in one place, or may be distributed on a plurality of network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the solution of the present embodiment. One of ordinary skill in the art can understand and implement it without inventive effort.

Through the above description of the embodiments, those skilled in the art will clearly understand that each embodiment can be implemented by software plus a necessary general hardware platform, and certainly can also be implemented by hardware. With this understanding in mind, the above-described technical solutions may be embodied in the form of a software product, which can be stored in a computer-readable storage medium, such as ROM/RAM, magnetic disk, optical disk, etc., and includes instructions for causing a computer device (which may be a personal computer, a server, or a network device, etc.) to execute the methods of the various embodiments or some parts of the embodiments.

Finally, it should be noted that: the above examples are only intended to illustrate the technical solution of the present invention, but not to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; and such modifications or substitutions do not depart from the spirit and scope of the corresponding technical solutions of the embodiments of the present invention.

Claims

1. A method for quantifying the influence of a backwater jacking on water level change is characterized by comprising the following steps:

determining a water level change response characteristic and a contribution rate of the water level change response characteristic to the water level change of the target river reach according to the backwater jacking hydrological simulation model based on the target hydrological data of the target river reach in a target time interval; wherein the water level change response characteristic is a factor affecting the water level change of the target river reach;

the method comprises the following steps of determining a backwater jacking hydrological simulation model based on historical hydrological data of a target river reach, and specifically comprises the following steps:

determining a backwater jacking hydrological simulation model based on the hydrological data of the upstream and downstream control sections in the research period; the backwater jacking hydrological simulation model takes an upstream control section water level and a downstream control section water level as input, and takes an upstream control section flow as output;

the method for determining the backwater jacking hydrological simulation model based on the hydrological data of the upstream and downstream control sections in the research period specifically comprises the following steps:

Q＝α(Z_u-Z_d)^β(Z_u-Z₀)^b；

in the formula, Q is the flow of an upstream control section; z_uFor upstream control of the level of the cross-section, Z_dControlling the section water level for the downstream; z₀α, β and b are model undetermined parameters.

2. The method for quantifying the influence of the backwater roof support on the water level change according to claim 1, wherein the determining of the water level change response characteristic and the contribution rate of the water level change response characteristic to the water level change of the target river section according to the backwater roof support hydrological simulation model based on the target hydrological data of the target river section in the target time period specifically comprises:

3. The method for quantifying the influence of the backwater roof support on the water level change according to claim 2, wherein the determining of the water level change response characteristic based on the target hydrological data of the target river reach at the target time interval according to the backwater roof support hydrological simulation model specifically comprises:

4. The method for quantifying the influence of the backwater jacking on the water level change according to claim 1, wherein the determining of the model undetermined parameter of the backwater jacking hydrological simulation model calculation formula based on the hydrological data of the upstream and downstream control sections of the research period specifically comprises:

5. The method for quantifying the influence of the backwater top support on the water level change according to claim 4, wherein the determining of the model undetermined parameter of the backwater top support hydrological simulation model calculation formula based on the model rate timing data specifically comprises:

6. A system for quantifying the influence of a backwater jacking on water level variation is characterized by comprising: the hydrological model building unit and the water level change analyzing unit;

the water level change analysis unit is used for determining a water level change response characteristic and a contribution rate of the water level change response characteristic to the water level change of the target river reach according to the backwater roof support hydrological simulation model based on target hydrological data of the target river reach in a target time period; wherein the water level change response characteristic is a factor affecting the water level change of the target river reach;

Q＝α(Z_u-Z_d)^β(Z_u-Z₀)^b；

7. An electronic device, comprising a memory and a processor, wherein the processor and the memory communicate with each other via a bus; the memory stores program instructions executable by the processor, the processor calling the program instructions capable of performing a method of quantifying the effect of backwater jacking on water level changes as claimed in any one of claims 1 to 5.

8. A non-transitory computer readable storage medium having stored thereon a computer program, which when executed by a processor implements a method of quantifying the effect of a backwater jacking on a water level change as claimed in any one of claims 1 to 5.