CN104047256A - Water level response estimation method of river bed evolutions in different areas under hydrodynamism - Google Patents

Abstract

A water level response estimation method of river bed evolutions in different areas under hydrodynamism comprises the following steps: collecting runoff data of riverway areas to be estimated since hydrologic records, determining dominant discharge, and selecting a dominant formative runoff date according to the type of a tide to actually measure the tide level process at the river mouth; acquiring an actually measured natural river bed topographic map before and after the dominant formative runoff date; acquiring the geological data of the natural river bed, and determining the burial depth and the width of sand beds on cross sections; determining the characteristic parameters of bed load and suspended load through a soil test; establishing a flow and sediment mathematics calculation model according to the basis data; determining the roughness of the natural river bed through the water level verification, the sand content verification of the suspended load, and erosion-siltation verification of a terrain; analyzing the evolution property of the natural river bed under the common effect of dominant formative runoff and the tideway, and classifying the evolution property of the river bed in three groups under hydrodynamism; forecasting the future riverway water level change rule under hydrodynamism.

Description

The water level response appraisal procedure of zones of different river bed change under hydrodynamism

[technical field]

The present invention relates to Hydraulics and River Dynamics Technical Development Area, specifically the water level response appraisal procedure of zones of different river bed change under a kind of hydrodynamism.

[background technology]

Natural stream channel is under the Natural Water dynamic actions such as runoff and tide, or the natural phenomena deforming due to the human intervention such as dig sand, build a dam, and is referred to as river bed change.The impact of river bed change involves a wide range of knowledge, " pull one hair and move the whole body ", because of river bed change, maximum power station, East China Shuikou Hydraulic Station on the Min River, Fujian Province, the golden pheasant large gate on Jinjiang, partial loss of function or the subject to severe risks of damage that the important water conservancy projectss such as large gate and western small stream large gate are drawn in the north on Jiulongjiang River, even rebuild, cause tremendous economic loss; Moreover, due to river bed change, on the Min River and Jiulongjiang River, there are the Wan Shouqiao of centuries history, big vast Shan Guqiao, east of a river Gu Qiao and 15 ponds, family in succession to be ruined, river bed change also makes hydrodynamic condition change, shrink back in river mouth, wetland disappears, salty tide traces back, some getting water from water head site mouths of Fujian Province provincial capital Foochow change because river bed change causes flow condition, chlorine ion concentration was once exceeding standard ten times, scrap because hydrodynamic condition changes the precious new diversion works in Zhangzhou City and the second water works, Zhangzhou City, has a strong impact on field irrigation and urban drinking water safety.

Under elemental effect, the development in following riverbed, to rest in the following river characteristics of motion under runoff and tide acting in conjunction to change crucial, be directly connected to city intake water mouth, across Jiang Qiaoliang, wear river subway, shipping and city dyke etc. relate to the safety of river building, most important to the sustainable development of two sides, river economic society.

[summary of the invention]

The invention provides the water level response appraisal procedure of zones of different river bed change under a kind of hydrodynamism, the method can disclose the deformation characteristic of natural stream channel under hydrodynamism, determine under runoff and tide acting in conjunction, the following water level variation of each cross-section of river of natural river, for relating to the construction service of river building.

The present invention is achieved in that

Under hydrodynamism, the water level response appraisal procedure of zones of different river bed change, comprises the steps:

Step 1: collected the Streamflow Data since there is hydrologic record in region, river course to be assessed, determine channel forming disahcge, tidal stencils is selected to make a runoff a day river mouth actual measurement tidal level process is occurred;

Step 2: gather and make a runoff generation rear natural stream channel actual measurement topographic map a few days ago;

Step 3: gather natural stream channel geologic information, determine each section sand bed buried depth, sand bed width;

Step 4: the characteristic parameter of determining bed load and suspended load by soil test;

Step 5: according to above-mentioned basic data, set up the husky computational mathematics model of water;

Step 6: by water level verify, suspended load sand content checking, landform erosion and deposition verify, rule is determined natural stream channel roughness;

Step 7: make natural stream channel under a runoff and trend acting in conjunction and develop property analysis, under hydrodynamism, river bed change character three classes are divided: specifically comprise:

If natural river course total length is Lt, extracting river course calculating section number is n, and through k hydrodynamism, it is Dimax that extraction river course respectively calculates section limiting scour, i=1～n, riverbed overall average dinting depth riverbed overall average incision speed the maximum incision speed of riverbed overall average $V\max =\frac{D_{\max }}{k},$ :

One class: range of instability

River is long is Lus=(30% ± 1%) * Lt;

Riverbed, region mean erosion depth Dusav=(310% ± 15%) * Dav;

Riverbed, region limiting scour Dusmax=(1350% ± 50%) * Dav;

The average incision speed in riverbed, region

The maximum incision speed in riverbed, region

Two classes: transition region

River is long is Ltr=(15% ± 1%) * Lt;

Riverbed, region mean erosion depth Dtrav=(67% ± 3%) * Dav;

Riverbed, region limiting scour Dtrmax=(376% ± 10%) * Dav;

The average incision speed in riverbed, region

The maximum incision speed in riverbed, region

Three classes: stable region

River is long is Ls=(55% ± 1%) * Lt;

Riverbed, region mean erosion depth Dsav=(17% ± 1%) * Dav;

Riverbed, region limiting scour Dsmax=(89% ± 4%) * Dav;

The average incision speed in riverbed, region

The maximum incision speed in riverbed, region

Step 8: under forecast hydrodynamism, following river water level Changing Pattern: with the long incision Dusmax in Lus river, territory, class one zone, simultaneously, keeping two, three class regions is present situation landform, in the time of can predicting generation riverbed, territory, class one zone limiting scour by the calculated with mathematical model of having set up, natural stream channel cross sections water level variation; With the long incision Dtrmax in Ltr river, territory, class two zone, meanwhile, keeping one, three class regions is present situation landform, in the time of can predicting generation riverbed, territory, class two zone limiting scour by the calculated with mathematical model of having set up, and natural stream channel cross sections water level variation; With the three long incision Dsmax in Ls rivers, class region, meanwhile, keep one, territory, class two zone is present situation landform, in the time of can predicting three generation riverbed, class region limiting scours by the calculated with mathematical model of having set up, natural stream channel cross sections water level variation.

The invention has the advantages that: 1, can verify under runoff and tide acting in conjunction, the Evolution Characteristics in natural stream channel future, define which riverbed, region basicly stable, which riverbed, region will incision, but amplitude is little, the still significantly incision of which riverbed, region, provides technical support for relating to river engineering construction; 2, can forecast under runoff, morning and evening tides acting in conjunction the Changing Pattern of the hydraulic elements such as following river water level, flow velocity, streamflow separation mouth, the split ratio of converging mouth, tidal current limit, tidal limit.

[accompanying drawing explanation]

The invention will be further described in conjunction with the embodiments with reference to the accompanying drawings.

Fig. 1 is that specific embodiment of the invention Lower Reaches of Min River is made the natural stream channel actual measurement Digital Topographic Map ' before a runoff occurs.

Fig. 2 is that specific embodiment of the invention Lower Reaches of Min River is made the natural stream channel actual measurement Digital Topographic Map ' after a runoff occurs.

Fig. 3 be the specific embodiment of the invention the husky computational mathematics model of water is carried out to water level proof diagram.

Fig. 4 be the specific embodiment of the invention the husky computational mathematics model of water is carried out to suspended load sand content proof diagram.

Fig. 5 be the specific embodiment of the invention the husky computational mathematics model of water is carried out to landform erosion and deposition proof diagram.

Fig. 6 is Lower Reaches of Min River river bed change feature figure under the hydrodynamism of the specific embodiment of the invention.

Fig. 7 is river bed change three class zoning plans under the hydrodynamism of the specific embodiment of the invention.

Under the hydrodynamism of the specific embodiment of the invention, there is a class river to drill water level variation figure of withered season of section under Shuikou Hydraulic Station dam in Fig. 8.

Under the hydrodynamism of the specific embodiment of the invention, there are two class rivers to drill water level variation figure of withered season of section under Shuikou Hydraulic Station dam in Fig. 9.

Under the hydrodynamism of the specific embodiment of the invention, there are three class rivers to drill section low water water level variation figure under Shuikou Hydraulic Station dam in Figure 10.

[specific embodiment]

The water level response appraisal procedure of zones of different river bed change under open fire dynamic action with a specific embodiment, comprises the steps: below

Step 1: amount to 5750 days Streamflow Datas year November January to 2010 nineteen ninety-five after maximum power station, the East China Shuikou Hydraulic Station on the collection Min River, Fujian Province is built up, and determines that channel forming disahcge is the peak flood flow 30600m of 2005 ³the peak flood flow 29400m of/s and 2006 ³/ s; Tidal stencils is selected to make a runoff Guanxi hydrometric station actual measurement tidal level process of day Min Jiang He Kou is occurred.

Step 2: gather Lower Reaches of Min River and make (as shown in Figure 1) in 2003 before a runoff occurs and make a runoff 2008 natural stream channel actual measurement Digital Topographic Map 's (as shown in Figure 2) after occurring.

Step 3: gather Lower Reaches of Min River natural stream channel 93km, the geologic information of 300 borings; Determine each section sand bed buried depth of natural stream channel, sand bed width, calculate sand bed area and sand bed equivalent buried depth.Coboundary is Shuikou Hydraulic Station actual measurement letdown flow process, and lower boundary is Min Jiang Kou Guanxi head and plum blossom hydrometric station measured water level graph.

Step 4: the characteristic parameter of determining bed load and suspended load by soil test.

Step 5: according to above-mentioned basic data, set up the husky computational mathematics model of water.

Step 6: the husky computational mathematics model of water is carried out to water level checking (as shown in Figure 3), suspended load sand content checking (as shown in Figure 4), landform erosion and deposition checking (as shown in Figure 5).

Step 7: after checking is satisfied, selected make a runoff and trend acting in conjunction by 6 times, natural stream channel is developed to character and be divided into range of instability, transition region and stable region.

Specifically comprise: according to Min River actual conditions, by within 6 times 2005 and 2006, making a runoff and trend acting in conjunction, obtain Lower Reaches of Min River river bed change state, extract 234 section river-bed deformation figure, every 5 sections are one group, amount to 58 groups, get its average for every group, Lower Reaches of Min River river bed change feature is as shown in Figure 6 under hydrodynamism, red in Fig. 6, yellow, blue three water surface curves, be respectively range of instability, riverbed, transition region and stable region, average dinting depth 4.72m is respectively organized in region, range of instability, organize maximum cutting-in degree 8.75m, organize minimum cutting-in degree 2.67m, transition region is respectively organized average dinting depth 1.27m, each organizes maximum cutting-in degree 1.93m, each organizes minimum cutting-in degree 0.25m, average dinting depth 0.22m is respectively organized in region, stable region, each organizes region maximum cutting-in degree 0.78m, each organizes region minimum cutting-in degree 0.04m.

Lower Reaches of Min River natural river course total length is L _t=88.12km, extracting river course calculating section number is 234, through 6 hydrodynamisms, riverbed overall average dinting depth D _av=1.310m, riverbed overall average incision speed V _av=0.218m/ time, V _max=2.95m/ time.

One class: range of instability

From mouth of a river dam site to Nanyang, the long 26.2km in section; Riverbed, region mean erosion depth Dusav=4.067m; Riverbed, region limiting scour Dusmax=17.700m; The average incision speed in riverbed, region Vusav=0.678m/ time; The maximum incision speed in riverbed, region Vusmax=2.950m/ time;

Two classes: transition region

From Nanyang to Tang, lift the long 12.87km in section; Riverbed, region mean erosion depth D _trav=0.875m; Riverbed, region limiting scour D _trmax=4.92m; Riverbed, region average incision speed V _trav=0.146m/ time; Riverbed, region maximum incision speed V _trmax=0.820m/ time;

Three classes: stable region

From Tang, lift to horse hair Bai Yantan the long 49.05km in section; Riverbed, region mean erosion depth Dsav=0.220m; Riverbed, region limiting scour Dsmax=1.17m; The average incision speed in riverbed, region Vsav=0.037m/ time; The maximum incision speed in riverbed, region Vsmax=0.195m/ time.

Step 8: under forecast runoff, morning and evening tides acting in conjunction, following river water level Changing Pattern:

In Fig. 8, square points curve is present situation typical case day 24 hours natural stream channel stage hydrographs, Diamond spot curve is that hydrodynamism is when one class river bed change occurs, from mouth of a river dam site to Nanyang, the long 26.2km in section, during generation area riverbed limiting scour 17.700m, 24 hours riverbed stage hydrographs.Can find out: days 24 hours natural stream channel SEA LEVEL VARIATION processes of section typical case same section riverbed water level change procedure when there is a class river bed change under withered season Shuikou Hydraulic Station dam, wherein, the former lowest water level 5.52m, the latter's lowest water level 5.47m;

In Fig. 9, square points curve is present situation typical case day 24 hours natural stream channel stage hydrographs, Diamond spot curve is hydrodynamism while there is two class river bed changes, from Nanyang to Tang, lifts the long 12.87km in section, during generation area riverbed limiting scour 4.92m, 24 hours riverbed stage hydrographs.Can find out: days 24 hours natural stream channel SEA LEVEL VARIATION processes of section typical case same section riverbed water level change procedure when there is two class river bed changes under withered season Shuikou Hydraulic Station dam, wherein, and the former lowest water level 5.52m, the latter's lowest water level 3.64m:

In Figure 10, square points curve is present situation typical case day 24 hours natural stream channel stage hydrographs, and Diamond spot curve is hydrodynamism while there is three class river bed changes, and Ji Cong Tang lifts to horse hair Bai Yantan, the long 49.05km in section, riverbed, region limiting scour D _smaxduring=1.17m, 24 hours riverbed stage hydrographs.Can find out: days 24 hours natural stream channel SEA LEVEL VARIATION processes of section typical case same section riverbed water level change procedure when there is three class river bed changes under withered season Shuikou Hydraulic Station dam, wherein, the former lowest water level 5.52m, the latter's lowest water level 5.52m.

The above; be only the specific embodiment of the present invention, but protection scope of the present invention is not limited to this, anyly belongs to those skilled in the art in the technical scope that the present invention discloses; the variation that can expect easily or replacement, all should be encompassed in protection scope of the present invention.

Claims (1)

1. the water level response appraisal procedure of zones of different river bed change under hydrodynamism, is characterized in that: comprise the steps:

Step 1: collected the Streamflow Data since there is hydrologic record in region, river course to be assessed, determine channel forming disahcge, tidal stencils is selected to make a runoff a day river mouth actual measurement tidal level process is occurred;

Step 2: gather and make a runoff generation rear natural stream channel actual measurement topographic map a few days ago;

Step 3: gather natural stream channel geologic information, determine each section sand bed buried depth, sand bed width;

Step 4: the characteristic parameter of determining bed load and suspended load by soil test;

Step 5: according to above-mentioned basic data, set up the husky computational mathematics model of water;

Step 6: by water level verify, suspended load sand content checking, landform erosion and deposition verify, rule is determined natural stream channel roughness;

Step 7: make natural stream channel under a runoff and trend acting in conjunction and develop property analysis, under hydrodynamism, river bed change character three classes are divided: specifically comprise:

If natural river course total length is Lt, extracting river course calculating section number is n, and through k hydrodynamism, it is Dimax that extraction river course respectively calculates section limiting scour, i=1～n, riverbed overall average dinting depth $\mathrm{Dav}=\frac{\underset{i=1}{\overset{n}{\mathrm{\Σ}}}{D}_{i\max }}{n},i=1~n,$ Riverbed overall average incision speed $\mathrm{Vav}=\frac{D_{\mathrm{av}}}{k},$ The maximum incision speed of riverbed overall average $V\max =\frac{D_{\max }}{k},$ :

One class: range of instability

River is long is Lus=(30% ± 1%) * Lt;

Riverbed, region mean erosion depth Dusav=(310% ± 15%) * Dav;

Riverbed, region limiting scour Dusmax=(1350% ± 50%) * Dav;

The average incision speed in riverbed, region

The maximum incision speed in riverbed, region

Two classes: transition region

River is long is Ltr=(15% ± 1%) * Lt;

Riverbed, region mean erosion depth Dtrav=(67% ± 3%) * Dav;

Riverbed, region limiting scour Dtrmax=(376% ± 10%) * Dav;

The average incision speed in riverbed, region

The maximum incision speed in riverbed, region

Three classes: stable region

River is long is Ls=(55% ± 1%) * Lt;

Riverbed, region mean erosion depth Dsav=(17% ± 1%) * Dav;

Riverbed, region limiting scour Dsmax=(89% ± 4%) * Dav;

The average incision speed in riverbed, region

The maximum incision speed in riverbed, region

Step 8: under forecast hydrodynamism, following river water level Changing Pattern: with the long incision Dusmax in Lus river, territory, class one zone, simultaneously, keeping two, three class regions is present situation landform, in the time of can predicting generation riverbed, territory, class one zone limiting scour by the calculated with mathematical model of having set up, natural stream channel cross sections water level variation; With the long incision Dtrmax in Ltr river, territory, class two zone, meanwhile, keeping one, three class regions is present situation landform, in the time of can predicting generation riverbed, territory, class two zone limiting scour by the calculated with mathematical model of having set up, and natural stream channel cross sections water level variation; With the three long incision Dsmax in Ls rivers, class region, meanwhile, keep one, territory, class two zone is present situation landform, in the time of can predicting three generation riverbed, class region limiting scours by the calculated with mathematical model of having set up, natural stream channel cross sections water level variation.