A rapid storage method of rainwater and flood based on GM grey model

Abstract

The invention discloses a rainwater rapid storage method based on the GM grey model. The first step is to collect historical average rainfall and groundwater level data, and establish a model between the multi-year monthly average rainfall Y and the groundwater level x; the second step is to establish a GM grey model between the monthly average rainfall and the rainfall frequency according to the multi-year monthly average rainfall corresponding to different rainfall occurrence frequencies; the third step is to obtain the monthly average rainfall under the design rainfall guarantee rate according to the GM grey model and the flood season design rainfall guarantee rate, and obtain the groundwater level distribution under the flood season design rainfall guarantee rate according to the model in the first step; the fourth step is to establish an anti-seepage wall according to the groundwater level distribution in the third step. Through the prediction of the flood season groundwater level, the horizontal perforated pipe and the vertical perforated pipe are set in a targeted manner, so that the flood season rainwater is introduced into the pores of the aquifer, and the underground reservoir surrounded by the underground anti-seepage wall is filled, thereby improving the utilization rate of the flood season rainwater.

Description

Technical Field

[0001] The invention belongs to the technical field of rapid storage of rainwater and flood, and in particular relates to a rapid storage method of rainwater and flood based on a GM grey model. Background Art

[0002] With the development of the economy and society, the contradiction between water use for production and life and water use for ecological environment has become increasingly prominent. Improving the utilization rate of surface water resources, especially increasing the ecological water supply in the dry season and improving the ecological water supply guarantee rate by intercepting and storing rainwater and flood water, is particularly important for improving the regional ecological environment and promoting the construction of water ecological civilization.

[0003] There are areas with thick Quaternary alluvial deposits in the valleys and alluvial plains in front of the mountains, which are suitable for building underground reservoirs to store and utilize rainwater. Determining the scope and height of the underground anti-seepage wall of the underground reservoir is the basis for building an underground reservoir, but the application of existing theories in this regard is still blank.

[0004] In view of the fact that rain and flood waters during the flood season rise and fall sharply and last for a short time, the key to improving the utilization rate of rain and flood water is to intercept and store as much rain and flood water as possible and quickly direct it into underground reservoirs. Summary of the invention

[0005] The purpose of the present invention is to provide a rapid storage method for rainwater based on the GM grey model, so as to intercept and store as much rainwater as possible and quickly introduce the rainwater into the underground reservoir, thereby achieving the purpose of improving the utilization rate of rainwater and improving the regional ecological environment.

[0006] The object of the present invention is achieved by the following technical means, a rainwater rapid storage method based on the GM grey model, comprising the following steps:

[0007] The first step is to collect historical average rainfall and groundwater level data and establish a model between the multi-year monthly average rainfall Y and the groundwater level x;

[0008] The second step is to establish the GM grey model GM (1,1) between the monthly average rainfall and the rainfall frequency according to the multi-year monthly average rainfall corresponding to different rainfall frequencies;

[0009] The third step is to obtain the average monthly rainfall under the design rainfall guarantee rate based on the GM gray model established in the second step and the design rainfall guarantee rate during the flood season, and to obtain the groundwater level distribution under the design rainfall guarantee rate during the flood season based on the model in the first step;

[0010] Step 4: Build an anti-seepage wall according to the groundwater level distribution in step 3;

[0011] In the fourth step, the scope and height of the underground anti-seepage wall of the regional underground reservoir are determined in combination with the minimum burial depth requirements of the regional groundwater level;

[0012] In the first step, the model between the multi-year monthly average rainfall Y and the groundwater level x is Y=e cx+d ;

[0013] The specific method of establishing the GM grey model GM (1,1) between the monthly average rainfall and the rainfall frequency is as follows:

[0014] S1, analyze the corresponding monthly average rainfall value Y under different rainfall occurrence frequencies p of 5%~50% from January to December i , i represents the month, i=1~12;

[0015] S2, the original monthly average rainfall Y at different frequencies in a single month i （0） =(Y i （0） (5%),Y i （0） (10%)...Y i （0） (50%)), perform an accumulation, and generate a sequence of Y i （1） =(Y i （1） (5%),Y i （1） (10%)…Y i （1） (50%));

[0016] S3, the monthly cumulative sequence Y obtained from S2 i （1） , establish the monthly average rainfall prediction GM gray model GM (1,1): , whose discrete form is

[0017] , k=1,2,…,9; p=5k;

[0018] S4, based on S3, the least squares method is used to determine the parameters a and u as follows;

[0019]

[0020] in: ,

[0021] S5, repeat S2, S3 and S4 to establish the GM grey model GM (1,1) for the monthly average rainfall prediction of each month.

[0022] In the fourth step, the scope and height of the underground anti-seepage wall of the regional underground reservoir are determined in combination with the minimum burial depth requirement of the regional groundwater level.

[0023] Within the underground warehouse, transverse perforated pipes arranged transversely along the horizontal plane are evenly distributed.

[0024] The transverse perforated pipes arranged transversely along the horizontal plane are also connected to vertical perforated pipes extending vertically downwards, so as to guide the rainwater in the flood season into the pores of the aquifer.

[0025] The transverse perforated pipes have multiple layers, and the burial depth of the uppermost layer of transverse perforated pipes is the same as the minimum burial depth requirement of the area.

[0026] The beneficial effects of the present invention are as follows: by predicting the range and depth of the groundwater level during the flood season, horizontal perforated pipes and vertical perforated pipes are set in a targeted manner, so that rainwater during the flood season is introduced into the pores of the aquifer, filling the underground reservoir surrounded by the underground anti-seepage wall, storing rainwater to the maximum extent, improving the utilization rate of rainwater during the flood season, and having good social, economic and ecological environmental benefits. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a flow chart of the rapid storage method of rainwater and flood based on GM grey model;

[0028] Figure 2 To design the regional groundwater level distribution map under the guaranteed rainfall rate;

[0029] Figure 3 Open-hole pipe distribution map for rapid storage of stormwater;

[0030] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments. DETAILED DESCRIPTION

[0031] [Example 1]

[0032] like Figure 1 As shown, a rapid storage method for rainwater based on the GM grey model includes the following steps:

[0033] The first step is to collect historical average rainfall and groundwater level data and establish a model between the multi-year monthly average rainfall Y and the groundwater level x;

[0034] The second step is to establish the GM grey model GM (1,1) between the monthly average rainfall and the rainfall frequency according to the multi-year monthly average rainfall corresponding to different rainfall frequencies;

[0035] The third step is to obtain the average monthly rainfall under the design rainfall guarantee rate based on the GM gray model established in the second step and the design rainfall guarantee rate during the flood season, and to obtain the groundwater level distribution under the design rainfall guarantee rate during the flood season based on the model in the first step;

[0036] The fourth step is to build an anti-seepage wall based on the groundwater level distribution in the third step.

[0037] like Figure 2 As shown, the groundwater level in the groundwater level monitoring well is used to obtain the data in the underground aquifers at each depth, and a model between the multi-year monthly average rainfall Y and the groundwater level x is established through historical data;

[0038] According to the historical data, a GM grey model GM (1,1) is established between the monthly average rainfall and the rainfall frequency; the rainfall frequency is obtained according to the historical average rainfall and can be obtained by a known method.

[0039] According to the GM gray model GM (1,1) between the monthly average rainfall and the rainfall frequency, as well as the design rainfall guarantee rate, the monthly average rainfall under the design rainfall guarantee rate is obtained. Then, according to the model between the multi-year monthly average rainfall Y and the groundwater level x, the groundwater level distribution under this monthly average rainfall is determined. The groundwater level distribution is as follows: Figure 2 As shown, we can understand the scope of water accumulation in each underground aquifer and the depth of the underground aquifer containing water, so as to understand the scope and height of the groundwater level distribution, and design the scope and depth of the anti-seepage wall in a targeted manner.

[0040] In the first step, the model between the multi-year monthly average rainfall Y and the groundwater level x is Y=e cx+d The specific values ​​of c and d are obtained by the data fitting method of exponential function.

[0041] The specific method of establishing the GM grey model GM (1,1) between the monthly average rainfall and the rainfall frequency is as follows:

[0042] S1, analyze the corresponding monthly average rainfall value Y under different rainfall occurrence frequencies p of 5%~50% from January to December i , i represents the month, i=1~12;

[0043] S2, the original monthly average rainfall Y at different frequencies in a single month i （0） =(Y i （0） (5%),Y i （0） (10%)...Y i （0） (50%)), perform an accumulation, and generate a sequence of Y i （1） =(Y i （1） (5%),Y i （1） (10%)…Y i（1） (50%));

[0044] S3, the monthly cumulative sequence Y obtained from S2 i （1） , establish the monthly average rainfall prediction GM gray model GM (1,1): , whose discrete form is

[0045] , k=1,2,…,9; p=5k (%). Among them, k and p are constants.

[0046] S4, based on S3, the least squares method is used to determine the parameters a and u as follows;

[0047]

[0048] in: ,

[0049] S5, repeat S2, S3 and S4 to establish the grey model GM (1,1) for the average monthly rainfall prediction for each month.

[0050] In S2, S3 and S4, a grey model GM (1,1) for the average monthly rainfall prediction of a single month, for example, January, is established in turn; then S2, S3 and S4 are repeated to establish the grey model GM (1,1) for the average monthly rainfall prediction of February, March ... December.

[0051] After establishing the gray model GM (1,1) for predicting the average monthly rainfall from January to December, the future average monthly rainfall is predicted according to the designed rainfall guarantee rate, and the predicted groundwater level distribution map is obtained through the model between the multi-year monthly average rainfall Y and the groundwater level x to predict the range and depth of groundwater during the rainy season, so as to design the range and burial depth of the anti-seepage wall to store the sudden precipitation during the rainy season in the reservoir formed by the anti-seepage wall.

[0052] [Example 2]

[0053] like Figure 2 and Figure 3 As shown, in the fourth step, the scope and height of the underground anti-seepage wall of the regional underground reservoir are determined in combination with the minimum burial depth requirement of the regional groundwater level.

[0054] like Figure 2 As shown in the figure, after obtaining the distribution of groundwater levels and establishing a model between the multi-year monthly average rainfall Y and the groundwater level x, the range and height of the underground anti-seepage wall, as well as the minimum requirement for the top depth of the anti-seepage wall, are determined in combination with the minimum burial depth requirement of the regional groundwater level. An anti-seepage wall is set outside the groundwater level range to enclose the water stored in the underground aquifer after the rain.

[0055] Within the underground warehouse, transverse perforated pipes arranged laterally along the horizontal plane are evenly distributed.

[0056] The horizontal perforated pipes arranged laterally along the horizontal plane are also connected to vertical perforated pipes pointing vertically downward to guide the rainwater in the flood season into the pores of the aquifer.

[0057] There are multiple layers of transverse perforated pipes, and the burial depth of the topmost layer of transverse perforated pipes is the same as the minimum burial depth requirement of the area.

[0058] like Figure 3 As shown, the horizontal perforated pipes and the vertical perforated pipes can quickly replenish rainwater to the underground aquifer, making full use of the advantage of rapid water replenishment in the pipe network, overcoming the disadvantage of slow natural water replenishment in the aquifer, catering to the characteristics of the flood season and achieving the purpose of rapid storage of rainwater.

[0059] At the same time, rainwater in the aquifer is blocked by the underground anti-seepage wall of the underground reservoir, so that the rainwater is quickly stored in the underground reservoir, improving the utilization rate of rainwater.

[0060] In actual use, Figure 3 As shown, horizontal and vertical perforated pipes are evenly arranged upstream of the Yongshui structure of the stream to evenly and quickly replenish rainwater and flood water in the stream to the underground reservoir; the underground reservoir is filled with rainwater through the interception and storage function of the surrounding anti-seepage walls.

Claims

1. A rapid storage method for rainwater based on GM grey model, characterized in that: The following steps are involved: The first step is to collect historical average rainfall and groundwater level data and establish a model between the multi-year monthly average rainfall Y and the groundwater level x; The second step is to establish the GM grey model GM (1,1) between the monthly average rainfall and the rainfall frequency according to the multi-year monthly average rainfall corresponding to different rainfall frequencies; The third step is to obtain the average monthly rainfall under the design rainfall guarantee rate based on the GM gray model established in the second step and the design rainfall guarantee rate during the flood season, and to obtain the groundwater level distribution under the design rainfall guarantee rate during the flood season based on the model in the first step; Step 4: Build an anti-seepage wall according to the groundwater level distribution in step 3; In the fourth step, the scope and height of the underground anti-seepage wall of the regional underground reservoir are determined in combination with the minimum burial depth requirements of the regional groundwater level; In the first step, the model between the multi-year monthly average rainfall Y and the groundwater level x is Y=e cx+d ; The specific method of establishing the GM grey model GM (1,1) between the monthly average rainfall and the rainfall frequency is as follows: S1, analyze the corresponding monthly average rainfall value Y under different rainfall occurrence frequencies p of 5%~50% from January to December i , i represents the month, i=1~12; S2, the original monthly average rainfall Y at different frequencies in a single month i （0） =(Y i （0） (5%),Y i （0） (10%)...Y i （0） (50%)), perform an accumulation, and generate a sequence of Y i （1） =(Y i （1） (5%),Y i （1） (10%)…Y i （1） (50%)); S3, the monthly cumulative sequence Y obtained from S2 i （1） , establish the monthly average rainfall prediction GM gray model GM (1,1): , whose discrete form is ,k=1,2,…,9;p=5k; S4, based on S3, the least squares method is used to determine the parameters a and u as follows; in: , S5, repeat S2, S3 and S4 to establish the GM grey model GM (1,1) for the monthly average rainfall prediction of each month.

2. The method for rapid storage of rainwater based on GM grey model according to claim 1 is characterized by: Within the underground warehouse, transverse perforated pipes arranged transversely along the horizontal plane are evenly distributed.

3. The method for rapid storage of rainwater based on GM grey model according to claim 2 is characterized by: The transverse perforated pipes arranged transversely along the horizontal plane are also connected to vertical perforated pipes extending vertically downwards, so as to guide the rainwater in the flood season into the pores of the aquifer.

4. The method for rapid storage of rainwater based on GM grey model according to claim 2 is characterized by: The transverse perforated pipes have multiple layers, and the burial depth of the uppermost layer of transverse perforated pipes is the same as the minimum burial depth requirement of the area.

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