Granular particle size decreasing calculation method and system for sealing concentrated leakage passage of earth and rockfill dam body

Abstract

The application discloses a method and system for calculating the particle size of a granular body for plugging concentrated leakage channels of an earth and rockfill dam body, and comprises the following steps: obtaining the dry bulk density r of the granular body s and the dry density p s ; establishing a corresponding relationship between the granular body with different particle sizes and sizes; respectively establishing calculation formulas of the underwater weight G i , the drag force F Di and the uplift force F Li of the granular body, and then establishing a moment balance calculation formula based on G i , F Di and F Li ; establishing a relationship between the particle size D i and the water flow velocity V i ; through on-site pigment tracing test, the particle sizes D i‑1 and D i of the granular body required for i-1 and i plugging are calculated; whether the difference between the particle sizes D i‑1 and D i of the granular body required for i-1 and i plugging meets a set condition is judged, if yes, further plugging is not needed; if not, further plugging is needed. The application solves the problems of horizontal conveying and range control of coarse granular material during plugging, and solves the problem of dynamic water plugging of a leakage channel with a leakage flow rate of m 3 / s and a cross section of m 2 .

Description

Technical Field

[0001] The present invention relates to the field of water conservancy and hydropower engineering, and in particular to a method and system for calculating the decreasing particle size of granular matter for blocking concentrated leakage channels in an earth-rock dam body. Background Art

[0002] There are 98,600 reservoir dams in service in my country. Since 1954, more than 3,500 dams have collapsed. Dam failure due to leakage is the leading cause of dam failure. Under the action of long-term high water head, the performance of the dam body and foundation deteriorates, and dam leakage is inevitable. If the leakage reaches m 3 / s level, especially the risk of earth-rock dam collapse has increased significantly, posing a serious threat to people's livelihood safety.

[0003] m 3 / S-class earth-rock dam concentrated leakage is a precursor to dam failure. With its large cross-section, large flow rate, and high flow velocity, the water flow continuously erodes the dam filling material. If it is not sealed in time, it can easily lead to catastrophic consequences. In addition, the southwest region of my country often encounters underground karst water seepage problems, which pose a major threat to project safety. For example: at the end of 2008, during the trial water storage of a large hydropower station in Guizhou, the karst cave connected to the No. 1 diversion tunnel was penetrated by the upstream reservoir water, and the water seepage flow rate reached 40.0m 3 / s, nearly causing huge economic losses by delaying the start of power generation by a year. Water blocking in the deep channels within the dam body and foundation is a hidden, deep underground project that requires complex technology and is extremely difficult to construct.

[0004] In response to the difficulties in sealing and emptying reservoirs during emergency operations and the lack of rapid emergency plugging technology, the engineering community has proposed a method of throwing coarse aggregate into the channel to block the leakage path of the dam body, namely the method of throwing loose granular plugging. The technical principle of this method is to throw loose granular materials into the deep permeable channels of the dam foundation through large-diameter holes in the ground, so that the water-passing section of the leakage channel in the dam body is gradually reduced until the entire section of the leakage channel is filled with loose granular materials to achieve the initial water blocking effect. Then, anti-seepage grouting is carried out using loose granular materials as the skeleton to achieve complete water blocking. However, some people believe that as sand and pebbles are thrown, the flow section of the water blocking section is reduced, the water flow velocity will inevitably increase, and the sand and pebbles will inevitably be washed away by the water flow, making it difficult to achieve the purpose of water blocking. In addition, due to the lack of theoretical guidance at present, some people still have doubts about throwing loose granular materials. Summary of the Invention

[0005] The conventional casting method is used for emergency plugging of concentrated leakage channels in earth-rock dam bodies, resulting in problems such as reduced flow section, increased water velocity, easy washing away of granular materials by water flow, and unsatisfactory plugging effect. Based on the principle of progressive filling with decreasing particle size, the present invention proposes a method and system for calculating the stable particle size of granular materials for plugging concentrated leakage channels in earth-rock dam bodies. The method uses the reverse reconstruction of the anti-filtration body plugging method of "progressive filling with decreasing particle size materials" to block the leakage path of dam body particles, achieving the leakage control goal of "active interception + hydraulic transition + anti-filtration protection", solving the problem of horizontal transportation and range control of coarse granular materials during leakage plugging, and overcoming the problem of dam body leakage flow rate of m 3 / s level, cross section up to m 2 It can be used specifically for emergency plugging of concentrated leakage channels in earth-rock dams and for reinforcement of earth-rock dam bodies.

[0006] In order to solve the above technical problems, the present invention is implemented through the following technical solutions:

[0007] In a first aspect, the present invention provides a method for calculating the particle size reduction of granular material for blocking concentrated leakage channels in an earth-rock dam body, comprising:

[0008] According to the test, the dry bulk density r of the granular body is obtained s and dry density ρ s ;

[0009] Establish the corresponding relationship between granular bodies of different particle sizes and their dimensions through measurement and calculation;

[0010] Establish underwater weight G respectively i , drag force F Di and upper lift F Li The calculation formula, based on G i 、F Di and F Li Establish the moment balance calculation formula;

[0011] Based on the moment balance calculation formula, the particle size D is established. i With water flow velocity V i The relationship between

[0012] Based on the established particle size D i With water flow velocity V i The relationship between the two is calculated by on-site pigment tracer test to obtain the particle size D required for the i-1th and i-th plugging. i-1 、D i ;

[0013] Determine the particle size D required for the i-1th and i-th plugging i-1 、D iIf the difference satisfies the set condition, further plugging is not needed; if the requirement is not satisfied, further plugging is needed.

[0014] As a further technical solution of the present application, the step of establishing the corresponding relationship between the different particle sizes of the granular body and the size by measurement calculation comprises:

[0015] Through the field measurement of the granular body, the length B i , the width L i , the height H i of the granular body with different particle sizes of 5-250mm are obtained, the particle size interval is 20mm, and the corresponding relationship between D i -f(B i , L i , H i ) is established.

[0016] As a further technical solution of the present application, the calculation formula of the underwater weight G i , the drag force F Di and the lifting force F Li is as follows:

[0017] G i =1 / 6×(r s -r)×π×D i 3 (1)

[0018]

[0019] The moment balance calculation formula established based on G i , F Di and F Li is as follows:

[0020] F Di ×L Di +F Li ×L Li =G i ×L Gi (4)

[0021] In formula (2)-(4), C Di is the flow resistance coefficient; C Li is the lifting coefficient; through the established corresponding relationship between D i -f(B i , L i , H i ), L Gi =L Li =1 / 2×L i , L Di =H i .

[0022] As a further technical solution of the present invention, the particle size D i With water flow velocity V i The relationship between them is as follows:

[0023]

[0024] ξ i =(4 / 3×L Gi / (C Li ×L Li +C Di ×L Di )) 1 / 2 (6)

[0025] In formula (6), ξ i is the process parameter; C Di is the flow resistance coefficient; C Li is the lifting coefficient; by establishing D i ~f(B i , L i 、H i ) correspondence, and L Gi =L Li =1 / 2×L i , L Di =H i .

[0026] As a further technical solution of the present invention, the particle size D required for the i-1th and i-th plugging is obtained by calculation. i-1 、D i The steps include:

[0027] The average water velocity V1 in the channel before the first plugging was calculated through the dye tracer test, and the particle size D1 required for the first plugging was calculated;

[0028] Repeat the pigment tracer test and particle size calculation to calculate the particle size D required for the i-1th and i-th plugging. i-1 、D i .

[0029] As a further technical solution of the present invention, the non-uniformity coefficient C of the granular body u and the curvature coefficient C C The calculation formula is as follows:

[0030] C u =D max / D min (7)

[0031] C c =D avg2 / (D min ×D max ) (8)

[0032] D min =min(D1, D2…D i-1 , D i ) (9)

[0033] D avg =(D1+D2+…+D i-1 +D i ) / i (10)

[0034] D min =max(D1, D2…D i-1 , D i ) (11)

[0035] Among them, the non-uniformity coefficient C u Required to be greater than or equal to 5, curvature coefficient C C The requirement is between 1 and 3.

[0036] As a further technical solution of the present invention, the particle size D i-1 、D i The difference between the two conditions meets the following conditions: (D i-1 -D i ) / D i-1 ≤10%.

[0037] In a second aspect, the present invention provides a system based on the above-mentioned method for calculating the particle size reduction of granular material for blocking concentrated leakage channels in an earth-rock dam body, the system comprising:

[0038] Granular physical parameter determination module: used to obtain the dry bulk density and dry density of granular materials based on experiments;

[0039] Particle size and size correspondence establishment module: through measurement and calculation, establish the correspondence between particles of different sizes and sizes;

[0040] Mechanical balance calculation module: includes underwater weight calculation unit, drag force calculation unit and lift force calculation unit, and establishes moment balance calculation formula based on the data output by these calculation units to evaluate the stability of granular bodies in water flow;

[0041] Particle size and water flow velocity relationship model construction module: Based on the moment balance calculation formula, the relationship between particle size and water flow velocity is constructed to predict the required particle size under different water flow velocities;

[0042] Plugging particle size calculation and field test module: Using pigment tracer tests and combining the particle size and water flow velocity relationship model, the particle size required for the i-1th and i-th plugging operations is calculated, and plugging is carried out on site.

[0043] Plugging effect evaluation module: Determine whether the difference in particle size between the i-1th and i-th plugging meets the set conditions. If so, it is determined that no further plugging is required; if not, further plugging is required until the set conditions are met.

[0044] In a third aspect, the present invention provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the method for calculating the decrease in particle size of granular matter for blocking concentrated leakage channels in an earth-rock dam body.

[0045] In a fourth aspect, the present invention provides a computer device comprising a processor and a memory, wherein the memory stores a computer program, and when the processor executes the computer program, it implements the method for calculating the decrease in particle size of granular matter for blocking the concentrated leakage channel of the earth-rock dam body.

[0046] Compared with the prior art, the present invention has the following beneficial effects:

[0047] (1) Based on the principle of "progressive filling with decreasing particle size materials," this paper proposes a novel method for calculating the stable particle size of granular materials for plugging concentrated seepage channels in earth-rockfill dams. This method effectively solves the plugging failure problem caused by the conventional casting method due to uniform particle size and lack of filtration protection by gradually reducing the particle size of the granular materials and utilizing the filtration protection between the granular materials.

[0048] (2) The present invention determines the stability of granular bodies under different water flow conditions by measuring detailed physical parameters (such as dry bulk density and dry density), establishing the corresponding relationship between particle size and size, and using a mechanical equilibrium calculation model. This method provides an accurate theoretical basis, making the plugging operation more scientific and reasonable. At the same time, the method also takes into account multiple factors such as water flow velocity, granular body particle size, drag force, and lifting force, making the calculation results more accurate and able to guide on-site personnel to perform precise plugging operations.

[0049] (3) Using methods such as dye tracer testing, the actual water flow velocity within the seepage channel is directly measured, and the particle size of the granular material used for subsequent plugging is adjusted accordingly. This method based on measured data ensures that each plugging operation can be optimally responded to the current situation, thereby gradually achieving the ideal plugging effect.

[0050] (4) For m 3To address the problem of high-flow leakage at the 1.5-1.5-meter level, this invention not only considers the initial plugging effect but also focuses on long-term anti-seepage performance. By setting the requirements for the unevenness coefficient and curvature coefficient of the granular body, a good gradation relationship between the fillers is ensured, forming a stable filter layer, effectively preventing the loss of fine particles, and further strengthening the dam structure.

[0051] (5) The method of the present invention is not only suitable for blocking concentrated leakage channels in earth-rock dams, but can also be widely used in leakage prevention and reinforcement projects in earth-rock dams. The application of this method will greatly improve the safety and stability of dams, providing a strong guarantee for the sustainable development of water conservancy and hydropower projects.

[0052] (6) The calculation method of the stable particle size of granular materials is reasonable and feasible, the parameters are easy to obtain, and it is convenient for actual engineering operation, providing a good theoretical basis for engineering implementation. BRIEF DESCRIPTION OF THE DRAWINGS

[0053] Figure 1 This is a calculation flow chart of the present invention.

[0054] Figure 2 It is a schematic diagram of the structure of the force calculation model of the concentrated leakage channel granular body of the present invention. DETAILED DESCRIPTION

[0055] The following describes specific embodiments of the present invention in conjunction with the accompanying drawings to facilitate understanding of the present invention by those skilled in the art. Obviously, the present invention is not limited to the scope of the specific embodiments. It will be apparent to those skilled in the art that as long as various modifications are within the spirit and scope of the present invention as defined and determined by the appended claims, such modifications are non-inventive work, and all inventions and creations utilizing the inventive concept of this law are protected.

[0056] Example 1

[0057] like Figure 1 As shown, this embodiment provides a method for calculating the particle size reduction of granular material for blocking concentrated leakage channels in an earth-rock dam body. The specific steps are as follows:

[0058] (1) Obtain the dry bulk density r of the granular material according to the test s (N / cm 3 ) and dry density ρ s (g / cm 3 ), r is the water density (N / cm 3 ).

[0059] (2) Establish the corresponding relationship between granular bodies of different particle sizes and their dimensions through measurement and calculation.

[0060] Specifically: Through the on-site measurement of granular materials, different particle sizes of 5mm to 250mm are obtained (using the equivalent particle size conversion method, that is, the volume of a sphere with equivalent diameter is equivalent to the volume of a hexahedron, D i =(6×B i ×L i ×H i / π)) 1 / 3 ) of the granular body i 、Width L i , high H i The representative size is 20mm, and the particle size difference is 20mm. i ~f(B i , L i 、H i ) can be represented by a table or a simulation function.

[0061] (3) Establish the underwater weight G of the granular body i , the drag force F of the water flow Di and upper lift F Li The calculation formula, without considering the cohesion and penetration, is based on G i 、F Di and F Li Establish the moment balance calculation formula, where F Di 、F Li The starting torque of the granular body, G i The calculation model of the drag force, lifting force and gravity of the granular body in the leakage channel is shown. Figure 2 shown.

[0062] Specifically: Establish underwater weight G i , drag force F Di and upper lift F Li The calculation formula is as follows:

[0063] G i =1 / 6×(r s -r)×π×D i 3 (1)

[0064]

[0065] Based on G i 、F Di and F Li The torque balance calculation formula is as follows:

[0066] F Di ×L Di +F Li ×L Li =G i ×LGi (4)

[0067] In formula (2)-formula (4), C Di is the flow resistance coefficient, C Di ≈1.0; C Li is the lifting coefficient, C Li ≈1.0; by establishing D i ~f(B i , L i 、H i ) correspondence, and L Gi =L Li =1 / 2×L i , L Di =H i .

[0068] (4) Based on the moment balance calculation formula, establish the particle size D i With water flow velocity V i The relationship between .

[0069] Specific: Establish particle size D i With water flow velocity V i The relationship between them is as follows:

[0070]

[0071] ξ i =(4 / 3×L Gi / (C Li ×L Li +C Di ×L Di )) 1 / 2 (6)

[0072] In formula (6), ξ i For process parameters.

[0073] (5) Based on the established particle size D i With water flow velocity V i The relationship between the two is calculated by on-site pigment tracer test to obtain the particle size D required for the i-1th and i-th plugging. i-1 、D i .

[0074] Specifically: Through the on-site pigment tracer test, colored pigments are poured into the channel, and the time when the pigments are found at the outlet is measured. Calculate the average water velocity V1 (m / s) in the channel before the first plugging, substitute it into formula (5) to calculate the granular particle size D1 required for the first plugging, and use this as a basis to carry out the first granular plugging throwing;

[0075] After the first casting is completed, wait until the water flow at the leakage channel outlet is stable, then pour the color pigment into the channel for the second time, measure the time when the pigment is found at the outlet, and calculate the average flow velocity V2 (m / s) of the water flow in the channel before the second plugging, so as to calculate the granular particle size D2 required for the second plugging, and use this as a basis for the second granular plugging casting;

[0076] The same method is used to obtain the average flow velocity V of the i-1th and i-th water flows respectively through the pigment tracer test. i-1 (m / s), V i (m / s), and thus calculate the particle size D required for the i-1th and i-th plugging i-1 、D i .

[0077] (6) Determine the particle size D required for the i-1th and i-th plugging operations i-1 、D i Does the difference between the two satisfy the set condition (D i-1 -D i ) / D i-1 ≤10%, if so, no further plugging is required; if it does not meet the requirements, further plugging is required.

[0078] Furthermore, the non-uniformity coefficient C of the granular body u and the curvature coefficient C C The calculation formula is as follows:

[0079] C u =D max / D min (7)

[0080] C c =D avg 2 / (D min ×D max ) (8)

[0081] D min =min(D1, D2…D i-1 , D i ) (9)

[0082] D avg =(D1+D2+…+D i-1 +D i ) / i (10)

[0083] D min =max(D1, D2…D i-1 , D i ) (11)

[0084] Among them, the non-uniformity coefficient C of the granular body is u Required to be greater than or equal to 5, curvature coefficient C C The requirement is between 1 and 3.

[0085] Example 2

[0086] A system based on the above-mentioned method for calculating the particle size reduction of granular material for blocking concentrated leakage channels in an earth-rock dam body, the system comprising:

[0087] Granular physical parameter determination module: used to obtain the dry bulk density and dry density of granular materials based on experiments;

[0088] Particle size and size correspondence establishment module: through measurement and calculation, establish the correspondence between particles of different sizes and sizes;

[0089] Mechanical balance calculation module: includes underwater weight calculation unit, drag force calculation unit and lift force calculation unit, and establishes moment balance calculation formula based on the data output by these calculation units to evaluate the stability of granular bodies in water flow;

[0090] Particle size and water flow velocity relationship model construction module: Based on the moment balance calculation formula, the relationship between particle size and water flow velocity is constructed to predict the required particle size under different water flow velocities;

[0091] Plugging particle size calculation and field test module: Using pigment tracer tests and combining the particle size and water flow velocity relationship model, the particle size required for the i-1th and i-th plugging operations is calculated, and plugging is carried out on site.

[0092] Plugging effect evaluation module: Determine whether the difference in particle size between the i-1th and i-th plugging meets the set conditions. If so, it is determined that no further plugging is required; if not, further plugging is required until the set conditions are met.

[0093] Example 3

[0094] This embodiment provides a computer-readable storage medium having a computer program stored thereon. When the program is executed by a processor, the method for calculating the decrease in particle size of granular matter for blocking concentrated leakage channels of an earth-rock dam body described in Example 1 is implemented.

[0095] Example 4

[0096] This embodiment provides a computer device including a processor and a memory, wherein the memory stores a computer program. When the processor executes the computer program, the method for calculating the decrease in particle size of granular matter for blocking the concentrated leakage channel of the earth-rock dam body described in Example 1 is implemented.

[0097] The present invention provides a system, computer-readable storage medium, and computer equipment based on the method. These technical integration and intelligent means make plugging operations more convenient and efficient, and also provide a technical foundation for future intelligent dam management.

[0098] In summary, the present invention has significant innovation and practicality in solving the problem of blocking concentrated leakage channels in earth-rock dam bodies. It not only improves the blocking efficiency and effect, but also provides a strong guarantee for the safe operation of water conservancy and hydropower projects.

[0099] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

[0100] The contents not described in detail in the specification of the present invention belong to the prior art known to those skilled in the art.

Claims

1. A method for calculating the particle size reduction of granular material for blocking concentrated leakage channels in earth-rock dam bodies, characterized in that: include: According to the test, the dry bulk density r of the granular body is obtained s and dry density ρ s ; Establish the corresponding relationship between granular bodies of different particle sizes and their dimensions through measurement and calculation; Establish the underwater weight G of the granular body i , the drag force F of the water flow Di and upper lift F Li The calculation formula, based on G i 、F Di and F Li Establish the moment balance calculation formula; Based on the moment balance calculation formula, the particle size D is established. i With water flow velocity V i The relationship between Based on the established particle size D i With water flow velocity V i The relationship between the two is calculated by on-site pigment tracer test to obtain the particle size D required for the i-1th and i-th plugging. i-1 、D i ; Determine the particle size D required for the i-1th and i-th plugging i-1 、D i Whether the difference meets the set conditions, if so, no further blocking is required; If the requirements are not met, further blocking is required; The step of establishing the corresponding relationship between granular bodies of different particle sizes and sizes by measurement and calculation includes: Through the on-site measurement of granular materials, the length B of granular materials with different particle sizes of 5 to 250 mm is obtained. i 、Width L i , high H i Size, particle size difference is 20mm, establish D i ~f(B i 、L i 、H i ) between them; The underwater weight G of the granular body is established respectively. i , the drag force F of the water flow Di and upper lift F Li The calculation formula is as follows: G i =1 / 6×(r s -r)×π×D i 3 (1) The G-based i 、F Di and F Li The torque balance calculation formula is as follows: F Di ×L Di +F Li ×L Li =G i ×L Gi (4) In formula (2)-formula (4), C Di is the flow resistance coefficient; C Li is the lifting coefficient; by establishing D i ~f(B i 、L i 、H i ) correspondence, and L Gi =L Li =1 / 2×L i , L Di =H i ; The established particle size D i With water flow velocity V i The relationship between them is as follows: x i =(4 / 3×L Gi / (C Li ×L Li +C Di ×L Di )) 1 / 2 (6) In formula (6), ξ i is the process parameter; C Di is the flow resistance coefficient; C Li is the lifting coefficient; by establishing D i ~f(B i 、L i 、H i ) correspondence, and L Gi =L Li =1 / 2×L i , L Di =H i .

2. The method for calculating the decreasing particle size of granular material for blocking the concentrated leakage channel of the earth-rock dam according to claim 1 is characterized in that: The calculation obtains the particle size D required for the i-1th and i-th plugging. i-1 、D i The steps include: The average water velocity V1 in the channel before the first plugging was calculated through the dye tracer test, and the particle size D1 required for the first plugging was calculated; Repeat the pigment tracer test and particle size calculation to calculate the particle size D required for the i-1th and i-th plugging. i-1 、D i .

3. The method for calculating the decreasing particle size of granular material for blocking the concentrated leakage channel of the earth-rock dam according to claim 1 is characterized in that: The non-uniformity coefficient C of the granular body u and the curvature coefficient C C The calculation formula is as follows: C u =D max / D min (7) C c =D avg 2 / (D min ×D max ) (8) D min =min(D1,D2…D i-1 ,D i ) (9) D avg =(D1+D2+…+D i-1 +D i ) / i (10) D min =max(D1,D2…D i-1 ,D i ) (11) Among them, the unevenness coefficient C u Required to be greater than or equal to 5, curvature coefficient C C The requirement is between 1 and 3.

4. The method for calculating the decreasing particle size of granular material for blocking the concentrated leakage channel of the earth-rock dam according to claim 1 is characterized in that: The particle size D i-1 、D i The difference between the two conditions meets the following conditions: (D i-1 -D i ) / D i-1 ≤10%.

5. A system based on the method for calculating the decrease in particle size of granular material for blocking concentrated leakage channels in earth-rock dam bodies according to any one of claims 1 to 4, characterized in that: The system comprises: Granular physical parameter determination module: used to obtain the dry bulk density and dry density of granular materials based on experiments; Particle size and size correspondence establishment module: through measurement and calculation, establish the correspondence between particles of different sizes and sizes; Mechanical balance calculation module: includes underwater weight calculation unit, drag force calculation unit and lift force calculation unit, and establishes moment balance calculation formula based on the data output by these calculation units to evaluate the stability of granular bodies in water flow; Particle size and water flow velocity relationship model construction module: Based on the moment balance calculation formula, the relationship between particle size and water flow velocity is constructed to predict the required particle size under different water flow velocities; Plugging particle size calculation and field test module: Using pigment tracer tests and combining the particle size and water flow velocity relationship model, the particle size required for the i-1th and i-th plugging operations is calculated, and plugging is carried out on site. Plugging effect evaluation module: Determine whether the difference in particle size between the i-1th and i-th plugging meets the set conditions. If so, it is determined that no further plugging is required; if not, further plugging is required until the set conditions are met.

6. A computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the method for calculating the decrease in particle size of granular material for blocking concentrated leakage channels in an earth-rock dam body as claimed in any one of claims 1 to 4.

7. A computer device comprising a processor and a memory, wherein the memory stores a computer program, and when the processor executes the computer program, it implements the method for calculating the decrease in particle size of granular material for blocking the concentrated leakage channel of the earth-rock dam body as described in any one of claims 1 to 4.

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