Precipitation parameter determination method considering economic and environmental influences

Abstract

The invention belongs to the technical field of precipitation parameter determination methods, and particularly relates to a precipitation parameter determination method considering economic and environmental influences, which considers engineering cost, influences on surrounding buildings, a precipitation range and a precipitation depth in a precipitation process, establishes an objective function and constraint conditions, and determines a permeability coefficient in the function. The method not only pursues the rainfall effect, but also considers the economic cost and the environmental influence at the same time, and realizes the comprehensive optimization among the cost, the environmental influence and the rainfall effect by establishing an optimization model comprising a plurality of targets and constraint conditions.

Description

Technical Field

[0001] The present invention belongs to the technical field of precipitation parameter determination methods, and in particular relates to a precipitation parameter determination method taking economic and environmental impacts into consideration. Background Art

[0002] Foundation pit dewatering is an important technical measure in the construction of earthwork, foundation and foundation engineering. Its main purpose is to remove moisture from the foundation pit soil, promote soil consolidation, improve foundation strength, and reduce lateral displacement and settlement of soil slopes, stabilize slopes, eliminate quicksand, and reduce the uplift of the base soil, so that the construction of foundation and foundation engineering located below natural groundwater can proceed smoothly. At present, the main purpose is simply to meet the design requirements of dewatering, and the impact on the economy and environment is not considered during the dewatering process.

[0003] The invention patent application with patent application number 201810801923.5 discloses a foundation pit dewatering optimization design method based on genetic algorithm and groundwater model, which then establishes an optimization model that takes into account the minimization of dewatering costs, and obtains the optimal foundation pit dewatering decision plan by repeatedly calling and running the groundwater flow simulation model.

[0004] It mainly uses genetic algorithms to optimize the location and pumping flow of precipitation wells to reduce construction costs. However, it does not consider environmental impact and the safety of surrounding buildings; that is, it does not find a balance between the environment and the economy. Moreover, it focuses on optimization at the technical and engineering levels, rather than the feasibility of actual operations and environmental sustainability. Summary of the invention

[0005] In response to the above technical problems, the present invention provides a method for determining precipitation parameters taking into account economic and environmental impacts, which minimizes costs by comprehensively considering project cost, pumping depth, pumping range and settlement amount.

[0006] In order to solve the above technical problems, the technical solution adopted by the present invention is:

[0007] A method for determining precipitation parameters that takes into account economic and environmental impacts. During the precipitation process, the project cost, the impact on surrounding buildings, the precipitation range, and the precipitation depth are considered to establish an objective function and constraint conditions, and determine the permeability coefficient in the function.

[0008] Among them: The required dewatering depth of the foundation pit is S 0 , m; precipitation range is M, m 2 ; The maximum allowable surface settlement range is M y , m 2 ; The maximum allowable underground pumping depth is S y ; The maximum allowable settlement depth of the ground surface is s y, mm; the total cost of the project cannot exceed Q'; suppose there are m precipitation wells, and the distances between each precipitation well are equal;

[0009] The functional expression of the project cost and the minimum impact on the surrounding environment is:

[0010] Q min =p 1 (Z 1 +Z 2 )+p 2 S′+p 3 R′+p4s′

[0011] Where: p 1 、p 2 、p 3 and p 4 are the weights corresponding to the project cost, pumping depth, pumping range and settlement respectively; Z 1 is the cost of pumping the well, Z 2 For pumping costs,

[0012] The constraints corresponding to different factors are as follows:

[0013]

[0014] The cost of pumping water from the well is Z 1 ,but:

[0015] Z 1 =m×v 1

[0016] Where: v 1 The unit price for building a pumping well.

[0017] The pumping cost is Z 2 ,but

[0018] Z 2 =m×S×v 2 .

[0019] Foundation pit dewatering will inevitably cause surface settlement. The settlement caused by dewatering (mm) is expressed by the following formula:

[0020]

[0021] Where: s is the final settlement, mm; ΔP is the average load applied to the soil layer by the water level change, kPa; Hi is the thickness of the calculated soil layer, m; Ei is the compression modulus of the soil layer, mPa.

[0022] The impact radius of precipitation is expressed as follows:

[0023]

[0024] Where: S is the water level drop during pumping, m; H is the aquifer thickness, m; K is the permeability coefficient, m / d;

[0025] The number of pumping wells and the required water level depth and water range are expressed as follows:

[0026] f(m)=S′

[0027] g(S′)=R′

[0028] Where: S' is the required precipitation depth S 0 The water depth that each pumping well needs to pump out when the pumping depth is S', m; R' is the pumping range when the pumping depth is S', m 2 .

[0029] Use soil drilling equipment to take soil, measure the moisture content of different soils, and determine the relationship between different soil depths above the water level and moisture content;

[0030] Before the precipitation begins, when the groundwater level is S', the soil at different depths in different parts is drilled and its moisture content is measured; assuming that the time when the precipitation depth reaches S" is t', the moisture content of the soil at the same depth in the original nearby parts is drilled at this time, and the permeability coefficient of the soil is determined by the relationship between time and moisture content;

[0031] When the soil permeability coefficient is determined, according to the formula Determine the impact range R of precipitation.

[0032] The soil drilling device includes a cylinder and a push plate, wherein the push plate is arranged in the cylinder and is slidably connected to the cylinder; the push plate is connected to a push rod; a limiter is arranged between the cylinder and the push plate; the soil is drilled by holding the push rod and using the blade at the lower end of the cylinder; after the soil is drilled, the limiter between the cylinder and the push plate is removed; the push rod is pushed, and the soil in the cylinder is pushed out by the push plate.

[0033] The cylinder and the push plate are limited by bolt connection.

[0034] Different weights are determined by expert scoring method; the expert scoring result is a data set of four parameters, each parameter contains multiple scoring results, and the entropy weight method is used to recalculate the result weights of the scoring results to obtain p 1 、p 2 、p 3 and p 4 The new weight of .

[0035] Compared with the prior art, the present invention has the following beneficial effects:

[0036] This method not only pursues precipitation effects, but also takes into account economic costs and environmental impacts. By establishing an optimization model containing multiple objectives and constraints, it achieves comprehensive optimization among costs, environmental impacts and precipitation effects.

[0037] By combining expert scoring with the entropy weight method, the weights of different objectives (such as project cost, pumping depth, pumping range and settlement) in the optimization model are scientifically determined, which improves the objectivity and accuracy of decision-making.

[0038] By establishing a mathematical model of precipitation-induced sedimentation and the radius of precipitation impact, the impact of precipitation projects on the surrounding environment can be quantitatively evaluated, providing a scientific basis for environmental protection. A variety of algorithms such as ant colony algorithm, particle swarm algorithm and fish swarm algorithm can be used to calculate the objective function value, and the average value is taken as the optimal solution, which improves the diversity and optimization of the solution.

[0039] The permeability coefficient is directly measured by a simple soil sampling device, which provides more accurate parameters for the precipitation plan and overcomes the problem that the permeability coefficient is difficult to accurately measure in traditional methods. The optimal distribution and number of precipitation wells are accurately calculated through the mathematical model of the precipitation influence radius, making the precipitation plan more scientific and reasonable.

[0040] By comprehensively evaluating the project cost, environmental impact and precipitation effect, comprehensive decision support is provided to decision makers, making the precipitation plan more in line with actual project needs.

[0041] Through innovations such as multi-objective optimization, scientific determination of weights, real-time monitoring, quantitative assessment of environmental impacts, algorithm diversity and optimization, direct determination of permeability coefficients, and precise calculation of precipitation impact range, a comprehensive, scientific, and efficient method for determining precipitation parameters is provided. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] Figure 1 It is a precipitation arrangement diagram of the present invention;

[0043] Figure 2 It is a structural schematic diagram of the soil drilling device of the present invention;

[0044] Figure 3 is a cross-sectional view of the soil drilling device of the present invention;

[0045] Among them: 1 is a cylinder, 2 is a push plate, 3 is a push rod, 4 is a bolt, and 5 is a blade. DETAILED DESCRIPTION

[0046] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments.

[0047] Example 1

[0048] The present invention no longer simply aims to meet the design requirements for precipitation, but takes into account the cost, impact on surrounding buildings, precipitation range, precipitation depth, and establishes an objective function and constraint conditions. Determination of the permeability coefficient in the function.

[0049] Precipitation parameter determination

[0050] 1. Computational model and principle

[0051] The required dewatering depth of the foundation pit is S 0 , m; precipitation range is M, m 2 ; The maximum allowable surface settlement range is M y , m 2 ; The maximum allowable underground pumping depth is S y ; The maximum allowable settlement depth of the ground surface is s y , mm; the total project cost cannot exceed Q'; suppose there are m precipitation wells, and the distances between each precipitation well are equal.

[0052] Assume the cost of pumping water from the well is Z 1 ,but:

[0053] Z 1 =m×v 1 (1)

[0054] Where: v 1 The unit price for building a pumping well.

[0055] Assume that the pumping cost is Z 2 ,but

[0056] Z 2 =m×S×v 2 (2)

[0057] Foundation pit dewatering will inevitably cause surface settlement. The settlement caused by dewatering (mm) can be expressed by the following formula:

[0058]

[0059] Where: s is the final settlement, mm; ΔP is the average load applied to the soil layer by the water level change, kPa; Hi is the thickness of the calculated soil layer, m; Ei is the compression modulus of the soil layer, mPa.

[0060] The impact radius of precipitation can be expressed as follows:

[0061]

[0062] Where: S is the water level drop during pumping, m; H is the aquifer thickness, m; K is the permeability coefficient, m / d.

[0063] From formula (4), it can be seen that the pumping range of a pumping well is related to the water level drop. When the water level drop range of a pumping well is to reach the required water level drop range and drop depth of the foundation pit, the water level drop must be much greater than the required drop depth S. 0 When more pumping wells are added, the dewatering range of multiple pumping wells will inevitably increase, and the dewatering depth must be less than the dewatering depth of one dewatering well. Therefore, the number of pumping wells and the required dewatering water level depth and dewatering range can be expressed by the following formula:

[0064] f(m)=S′ (5)

[0065] g(S′)=R′ (6)

[0066] Where: S' is the required precipitation depth S 0 The water depth that each pumping well needs to pump out when the pumping depth is S', m; R' is the pumping range when the pumping depth is S', m 2 .

[0067] Then the function expression of the project cost and the minimum impact on the surrounding environment is:

[0068] Q min =p 1 (Z 1 +Z 2 )+p 2 S′+p 3 R′+p4s′ (7)

[0069] Where: p 1 、p 2 、p 3 and p 4 They are the weights corresponding to the project cost, pumping depth, pumping range and settlement. The constraints corresponding to different factors are as follows:

[0070]

[0071] 2. Parameter determination and calculation method

[0072] like Figure 1 In the precipitation arrangement shown, the water level depth drops from S' to S", and the precipitation impact range expands from R' to R".

[0073] 2.1 Parameter determination

[0074] (1) Permeability coefficient

[0075] Soil is taken using a soil drilling device, and the moisture content of different soils is measured to determine the relationship between the moisture content and the different soil depths above the water level. As the precipitation work continues, the greater the precipitation depth, the greater the change in soil moisture content closer to the groundwater, and the smaller the moisture content of the surface soil within a certain range. As the precipitation depth continues to increase, the moisture content of the surface soil increases, and the affected range also increases.

[0076] Before the precipitation begins, when the groundwater level is S', the soil at different depths in different parts is drilled and its moisture content is measured. Assuming that the time when the precipitation depth reaches S' is t', the moisture content of the soil at the same depth in the original nearby parts is drilled at this time, and the permeability coefficient of the soil is determined by the relationship between time and moisture content.

[0077] (2) Precipitation impact range

[0078] When the soil permeability coefficient is determined, the influence range R of precipitation can be determined according to formula (4).

[0079] (3)p 1 、p 2 、p 3 and p 4 Determination

[0080] Different weights are determined by the expert scoring method. Since the precipitation location has different impacts on the surrounding area, the values ​​of the four weight parameters are different in different locations. The expert scoring result of the present invention is a data set of four parameters, and each parameter contains multiple scoring results. Multiple different weights will inevitably lead to complex calculations, different locations calculate different results, there may be contradictions between the results, and the calculation results will be larger or smaller, resulting in waste of resources. In order to overcome the influence of more data and the subjectivity of expert scoring, this paper uses the entropy weight method to recalculate the result weights of the scoring results to obtain p 1 、p 2 、p 3 and p 4 The new weight of .

[0081] Here are the steps:

[0082] The first step is to construct a matrix. Obtain the eigenvalue fuzzy matrix of each evaluation object;

[0083] The second step is data standardization, which is to make the original data dimensionless to make it comparable.

[0084] The third step is to calculate the proportion of each indicator;

[0085] The fourth step is to calculate the entropy value of each indicator;

[0086] Step 5: Calculate the coefficient of difference term;

[0087] Step 6: Calculate the weight of the indicator;

[0088] 2.2 Calculation method

[0089] The algorithm uses ant colony algorithm, particle swarm algorithm and fish swarm algorithm to calculate the objective function value, and selects the average of the three as the optimal value of the objective function. The algorithm is only used as a tool to implement the present invention, not as a specific invention right.

[0090] Example 2

[0091] Based on Example 1, this example proposes a simple soil sampling device for determining the moisture content of soil. The device is easy to operate and is convenient for real-time monitoring of precipitation conditions at the construction site.

[0092] The precipitation influence radius of the present invention requires the measurement of the permeability coefficient, and the measurement of the permeability coefficient can also indirectly analyze whether the precipitation scheme can meet the precipitation requirements.

[0093] The permeability coefficient is determined by using Darcy's theorem:

[0094]

[0095] Where: q is the seepage volume per unit time; L is the seepage distance; A is the water flow section; h 2 -h 1 is the water head difference between the two ends.

[0096] The invention proposes a simple soil sampling device for determining the water content of soil according to Darcy's theorem.

[0097] like Figure 2 and 3 As shown, the soil drilling device includes a cylinder 1 and a push plate 2, wherein the cylinder 1 is partially a hollow metal structure and the lower part is a metal blade 5. The push plate 2 is arranged in the cylinder 1 and is slidably connected to the cylinder 1; the push plate 2 is connected to a push rod 3; a limiter is arranged between the cylinder 1 and the push plate 2; by holding the push rod 3, the blade 5 at the lower end of the cylinder 1 is used to drill the soil; after the soil is drilled, the limiter between the cylinder 1 and the push plate 2 is removed; the push rod 3 is pushed, and the soil in the cylinder 1 is pushed out by the push plate 2.

[0098] Specifically, the position limit can be achieved by using bolts 4; corresponding connection holes are provided on the upper end of the cylinder 1 and the push plate 2; the bolts 4 are passed through the connection holes and the nuts are screwed on. To remove the position limit, only the nuts need to be loosened and the bolts 4 can be pulled out.

[0099] The specific implementation process is as follows:

[0100] 1. Drilling of soil

[0101] By holding the push rod 3, the blade 5 at the lower end of the cylinder 1 is used to drill the soil; after the soil is drilled, the limit between the cylinder 1 and the push plate 2 is removed; the push rod 3 is pushed, and the push plate 2 pushes out the soil in the cylinder 1 to obtain a cylindrical soil.

[0102] 2. Calculation of permeability coefficient:

[0103] Drill the soil from any area of ​​the construction site and divide the cylindrical soil into 1 part every 5 cm from top to bottom. Weigh each part m 1i , dry the soil and weigh it to m 2 , we can get the weight of water at different depths m i =m 1i -m 2 . Without considering the seepage distance L, h 2 -h 1 is the distance between different soil depths, A is the cross-sectional area of ​​cylinder 1, and the permeability coefficient of the soil in the vertical direction can be obtained according to formula (15).

[0104] 3. Analysis of water content in precipitation-affected areas:

[0105] Drill two soil bodies at different distances from the precipitation point in the precipitation area, and the elevations of the two soil bodies are the same. As in 1, measure the weight of water at the same depth in the two soil bodies, and compare the difference between the two weights to analyze whether the layout of the precipitation plan is reasonable. If the difference between the two is not large, but the weight difference with the soil water outside the area is large, it proves that the precipitation plan covers the precipitation area and the precipitation plan has little impact on the outside of the area.

[0106] Only the preferred embodiments of the present invention have been described in detail above, but the present invention is not limited to the above embodiments.

Claims

1. A method for determining precipitation parameters taking into account economic and environmental impacts, characterized in that: During the precipitation process, the project cost, the impact on surrounding buildings, the precipitation range and the precipitation depth are considered, and the objective function and constraint conditions are established to determine the permeability coefficient in the function; Among them: the required precipitation depth of the foundation pit is S0, m; the precipitation range is M, m 2 ; The maximum allowable surface settlement range is M y , m 2 ; The maximum allowable underground pumping depth is S y ; The maximum allowable settlement depth of the ground surface is s y , mm; the total cost of the project cannot exceed Q'; suppose there are m precipitation wells, and the distances between each precipitation well are equal; The functional expression of the project cost and the minimum impact on the surrounding environment is: Q min =p1(Z1+Z2)+p2S′+p3R′+p4s′ Where: p1, p2, p3 and p4 are the weights corresponding to the project cost, pumping depth, pumping range and settlement respectively; Z1 is the cost of the pumping well, Z2 is the pumping cost, The constraints corresponding to different factors are as follows:

2. A method for determining precipitation parameters considering economic and environmental impacts according to claim 1, characterized in that: The cost of pumping water from the well is Z1, then: Z1=m×v1 In the formula: v1 is the unit price of building a pumping well. If the pumping cost is Z2, then Z2=m×S×v2.

3. The method for determining precipitation parameters considering economic and environmental impacts according to claim 1, characterized in that: Foundation pit dewatering will inevitably cause surface settlement. The settlement caused by dewatering (mm) is expressed by the following formula: Where: s is the final settlement, mm; ΔP is the average load applied to the soil layer by the water level change, kPa; Hi is the thickness of the calculated soil layer, m; Ei is the compression modulus of the soil layer, mPa.

4. The method for determining precipitation parameters considering economic and environmental impacts according to claim 1, characterized in that: The impact radius of precipitation is expressed as follows: Where: S is the water level drop during pumping, m; H is the aquifer thickness, m; K is the permeability coefficient, m / d; The number of pumping wells and the required water level depth and water range are expressed as follows: f(m)=S′ g(S′)=R′ Where: S' is the water depth that each pumping well needs to pump when the required precipitation depth S0 is reached, m; R' is the pumping range when the pumping depth is S', m 2 .

5. A method for determining precipitation parameters taking into account economic and environmental impacts according to claim 1 or 4, characterized in that: Use soil drilling equipment to take soil, measure the moisture content of different soils, and determine the relationship between the moisture content and the depth of different soils above the water level; Before the precipitation begins, when the groundwater level is S', the soil at different depths in different parts is drilled and its moisture content is measured; assuming that the time when the precipitation depth reaches S" is t', the moisture content of the soil at the same depth in the original nearby parts is drilled at this time, and the permeability coefficient of the soil is determined by the relationship between time and moisture content; When the soil permeability coefficient is determined, according to the formula Determine the impact range R of precipitation.

6. A method for determining precipitation parameters taking into account economic and environmental impacts according to claim 5, characterized in that: The soil drilling device comprises a cylinder (1) and a push plate (2), wherein the push plate (2) is arranged in the cylinder (1) and is slidably connected to the cylinder (1); the push plate (2) is connected to a push rod (3); a limiter is provided between the cylinder (1) and the push plate (2); by holding the push rod (3), the soil is drilled using a blade (5) at the lower end of the cylinder (1); after the soil is drilled, the limiter between the cylinder (1) and the push plate (2) is removed; the push rod (3) is pushed, and the soil in the cylinder (1) is pushed out by the push plate (2).

7. A method for determining precipitation parameters taking into account economic and environmental impacts according to claim 6, characterized in that: The cylinder (1) and the push plate (2) are connected by bolts (4) to limit the position.

8. The method for determining precipitation parameters considering economic and environmental impacts according to claim 1, characterized in that: Different weights are determined through the expert scoring method; the expert scoring result is a data set of four parameters, each parameter contains multiple scoring results, and the entropy weight method is used to recalculate the result weights of the scoring results to obtain new weights of p1, p2, p3 and p4.

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