Design method of bilateral beveled flip bucket, flood discharge building and construction method

Abstract

The invention discloses a design method of a bilateral beveled flip bucket, a flood discharge building and a construction method, and relates to the technical field of water conservancy projects. The design method of the double-side beveled flip bucket comprises the following steps: firstly, designing a beveled diffusion bucket body type, and determining a hydraulic jump boundary on the beveled flip bucket according to an outlet hydraulic jump form under the designed lifting flow; a downstream bottom plate of the hydraulic jump boundary and a guide wall on the same side are cut off together to form a double-side beveled flip bucket, and double-side beveled vertexes correspond to the maximum emergent height; moving the beveled starting points on both sides along the upstream; on the premise that the positions of the beveled vertexes on the two sides are not changed, the reverse arc radius of the bottom plate is adjusted, the proportion of the water flow lifting angle to on-way outflow is changed, and the transverse positions of the beveled vertexes on the two sides are adjusted according to the arrangement of the downstream plunge pool or the river channel trend. According to the flood discharge building, the bilateral beveled flip bucket is designed through the bilateral beveled flip bucket design method. The construction method constructs the flood discharge building. The method has the beneficial effects of being good in adaptability, high in energy dissipation and scour prevention performance and wide in application prospect.

Description

Technical Field

[0001] The present invention relates to the technical field of water conservancy projects, and in particular to a design method for a double-sided beveled embankment, a flood discharge building and a construction method. Background Art

[0002] Many large and medium-sized hydropower projects are being planned and constructed in the southwest region. Most of these projects are located in high mountain valleys, and their flood discharge structures often employ a diversion energy dissipation method. This involves the flood discharge being ejected into the air through a diversion sill at the end of the structure, where it diffuses and picks up a large amount of air before falling into the downstream river channel or plunge pool. Because these projects exhibit high head, large flow, narrow valleys or plunge pools, and deep overburden during flood discharge, various types of diversion sills are required to ensure that the downstream water falls in the center of the river channel / plunge pond. At the same time, through air diffusion, the impact kinetic energy per unit area is minimized, thereby reducing the impact pressure and flow velocity in the downstream plunge pool, or alleviating local scour in the downstream river channel, thereby ensuring the safety of the energy dissipation structures or bank protection.

[0003] At present, the commonly used types of levees in China are mainly divided into two types: horizontal diffusion and vertical diffusion. The horizontal diffusion type levee is suitable for situations where the downstream water body is open, or the flood discharge structure is located on the shore, and the water flow needs to be projected to the center of the river channel, such as flat diffusion levee, tongue-shaped levee, unilateral diffusion levee, etc. Its characteristic is that while the water flow is diffusing laterally, the direction of the water flow can be changed to adjust the horizontal landing point of the water flow; the vertical diffusion type levee is suitable for situations where the downstream water surface is narrow, or the river channel downstream of the flood discharge structure is straight, such as narrow slit levee, wide tail pier, swallowtail levee, etc. Its characteristic is that the water flow is fully stretched longitudinally to adjust the longitudinal landing point of the water flow.

[0004] If a transversely diffused cantilever structure is used, there will be a problem of insufficient cantilever distance when the flow rate is small, and the water flow will easily hit the bank; if a longitudinally diffused cantilever structure is used, the water flow direction cannot be adjusted laterally. When the angle between the flood discharge structure and the river channel is large, it is also necessary to prevent the water flow from impacting the opposite bank under large flow rates.

[0005] Therefore, designing a type of ridge that can better disperse water tongues, dissipate energy in the air as much as possible, and has strong adaptability is a technical problem that needs to be solved urgently. Summary of the Invention

[0006] The technical problem to be solved by the present invention is that the horizontal diffusion embankment and the vertical diffusion embankment in the existing technology have certain defects and limited adaptability. The purpose is to provide a design method, a flood discharge building and a construction method for a double-sided beveled embankment, which adopts the corresponding technical scheme and has the beneficial effects of good adaptability, strong energy dissipation and anti-impact properties and broad application prospects.

[0007] The present invention is achieved through the following technical solutions: In a first aspect, the present invention provides a design method for a double-sided beveled ridge, which includes the following methods: S1. Design the shape of a single oblique diffuser sill and determine the hydraulic jump boundary line on the oblique diffuser sill based on the outlet hydraulic jump shape at the designed lift flow rate. S2. The bottom plate downstream of the hydraulic jump boundary line and the guide wall on the same side are removed to form a double-sided beveled overhang, and the double-sided beveled vertices of the double-sided beveled overhang correspond to the maximum exit height; S3. Under the premise that the position of the double-side bevel vertices remains unchanged, the bevel starting points on both sides are moved upstream to adjust the length of the double-side bevel; S4. Under the premise that the position of the double-sided bevel vertices remains unchanged, adjust the bottom plate anti-arc radius to change the water flow angle and the outflow ratio along the process.

[0008] S5. Adjust the lateral position of the bilateral bevel vertices according to the layout of the downstream plunge pond or the direction of the river.

[0009] Furthermore, in the present invention, in the above step S1, the outlet angle of the single-bevel diffuser is 10 degrees to 40 degrees, and the outlet height is 0m to 30m.

[0010] Furthermore, in the present invention, in the above step S1, the plane cutting angle of the single-bevel-cut diffusion step is 45±3 degrees.

[0011] Furthermore, in the present invention, in the above step S3, the double-sided beveled length of the double-sided beveled ridge is not less than 2 times the groove width, and the lateral width of the double-sided beveled ridge is not more than 2 times the groove width.

[0012] Furthermore, in the present invention, in the above step S3, the bilateral beveled edges are located upstream of the hydraulic jump boundary line.

[0013] In a second aspect, the present invention further provides a flood discharge building, characterized in that the double-sided beveled overhang is designed using the design method of the double-sided beveled overhang as described in claim 1.

[0014] Furthermore, in the present invention, when there are two or more flood discharge structures and they are arranged in the center of a river channel or a water cushion pond, the double-sided beveled embankments are arranged symmetrically, and the anti-arc curves of the embankment bottom plates are the same.

[0015] Furthermore, in the present invention, when there are two or more flood discharge structures and they are arranged on the bank of a river or a water cushion pond, the double-sided beveled embankments are arranged in an asymmetrical manner.

[0016] Furthermore, in the present invention, the above-mentioned method adjusts the starting point of the bottom plate anti-arc so that the inner ridge is low and the outer ridge is high. When multiple ridges discharge water together, the water flow overlaps in the air, the water flow position of the outer ridge is higher, and the water flow position of the inner ridge is lower, forming a dynamic water cushion to dissipate energy.

[0017] In a third aspect, the present invention further provides a construction method, characterized in that the flood discharge building as described in claim 6 is constructed.

[0018] Compared with the prior art, the present invention has the following advantages and beneficial effects: The present invention proposes a design method, flood discharge structure and construction method for a double-sided beveled sill. During the design, the water flow is diffused laterally by changing the double-sided bevel width; the water flow is stretched longitudinally by changing the double-sided bevel length; the water inflow direction is changed by adjusting the position of the double-sided bevel apex; the water inflow angle and the diversion ratio along the way are changed by adjusting the bottom arc radius of the double-sided beveled sill. The above optimized design is adopted during the design so that the flood discharge water inflow form can better adapt to the energy dissipation conditions of the narrow river valley and water cushion pond downstream, improve the energy dissipation and anti-scouring effect, and save engineering investment. The design method, flood discharge structure and construction method of the double-sided beveled sill of the present invention have important application value for the flood discharge and energy dissipation design of high dam projects. In the future, the present invention has broad application prospects in high-head hydropower stations planned and constructed in areas with high altitudes, high slopes and deep cover layers. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solutions of the exemplary embodiments of the present invention, the following briefly introduces the drawings required for use in the examples. It should be understood that the following drawings only illustrate certain embodiments of the present invention and should not be considered as limiting the scope. A person of ordinary skill in the art can also derive other relevant drawings based on these drawings without inventive effort. In the drawings: Figure 1 A schematic diagram of the double-sided beveled ridge of the present invention; Figure 2 A side view of the double-sided beveled ridge of the present invention (with the hydraulic jump portion removed); Figure 3 This is a schematic diagram of the top surface of the double-sided beveled ridge of the present invention; Figure 4 Schematic diagram of the single-bevel diffusion barrier of the present invention; Figure 5 Schematic diagram of the process of adjusting the starting position of the double-sided bevel cutting according to the present invention; Figure 6 This is a schematic diagram of the double-sided beveled ridge after the vertex position is adjusted according to the present invention; Figure 7 This is a schematic diagram of the double-sided beveled sill guide wall after position adjustment of the present invention; Figure 8 Schematic diagram of the optimized shape of the oblique diffusion ridge of the present invention.

[0020] The marks and corresponding parts names in the attached drawings are: 1- chute, 2- guide wall, 3- anti-arc bottom plate, 4- cantilever, 5- base, 6- anti-arc surface, 7- left cantilever, 8- right cantilever. DETAILED DESCRIPTION

[0021] In order to make the objects, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the embodiments and drawings. The schematic embodiments of the present invention and their description are only used to explain the present invention and are not intended to limit the present invention. The following detailed description of the embodiments of the present invention provided in the drawings is not intended to limit the scope of the claimed invention, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0022] It should be noted that similar numbers and letters represent similar items in the following figures. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in the subsequent figures. In the description of the embodiment of the present invention, "plurality" represents at least 2. In the description of the embodiment of the present invention, it should also be noted that, unless otherwise clearly stipulated and limited, the terms "setting", "installation" and "connection" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be a connection between the two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to the specific circumstances.

[0023] Example 1 This embodiment provides a design method for a double-sided beveled ridge, including the following methods: First, for flood discharge structures, the maximum outlet height of the cantilever must be determined. The solution is to first design a basic single-bevel diffuser shape at the outlet of the flood discharge structure. The plane bevel angle of the bevel diffuser shape is 45 degrees, the outlet cantilever angle is 10 degrees to 40 degrees (preferably 30 degrees in this embodiment), the outlet height is 0m to 30m (preferably 15m in this embodiment), and the bottom arc radius is 4 times to 10 times the water depth of the chute. Under the designed cantilever flow rate (usually the minimum working flow rate), a hydraulic jump occurs on the higher side of the outlet position of the bevel diffuser shape, and the cantilever cannot be normally cantilevered. At this time, the oblique hydraulic jump boundary line formed at the cantilever outlet can be observed and recorded.

[0024] Combine Figure 1As shown, to ensure that the water flow from the cantilever can be fully discharged at the designed cantilever discharge, the anti-arc bottom plate 3 downstream of the hydraulic jump boundary line and the guide wall 2 on the same side should be removed. Generally, the incision is also beveled, with the bevel vertex corresponding to the maximum discharge height, thus forming a double-sided bevel shape.

[0025] Furthermore, when the downstream water surface is narrow, in order to make full use of the energy dissipation of the downstream water body, the starting point of the double-sided bevel is adjusted longitudinally. Specifically, the position of the double-sided bevel apex remains unchanged, and the starting point of the double-sided bevel is moved upstream along the guide walls on both sides, so that the bevel length is increased, and the water flow is longitudinally pulled upstream. When adjusting, pay attention to controlling the near end of the water flow so that it will not hit the bank.

[0026] After determining the plane shape of the double-sided beveled ridge, combined with Figure 2 As shown, the anti-arc radius of the anti-arc surface 6 of the base of the double-sided beveled embankment can also be adjusted, the purpose is to change the outflow angle at the front end of the embankment and the outflow ratio along the double-sided beveled embankment, so that the flood discharge flow is evenly diffused longitudinally.

[0027] In the above process, the scheme can be optimized with the help of mathematical models first, and then the optimized mathematical model can be verified through physical models until the design protection requirements are met.

[0028] The design method in this embodiment is to design a base 5 with double-sided beveled embankments, the material of which is reinforced concrete. The base 5 can support the concrete structure of the upper material, and the base 5 is fixed on the bedrock of the bank slope.

[0029] Combine Figure 1 As shown, a double-sided beveled ramp is provided on either side of the chute 1, with diffusion guide walls 2 positioned at the end of the diffusing guide walls 2, which are the starting point of the double-sided bevels. Along the way, a reverse arc bottom plate 3 is formed, allowing water to flow freely from the outlet of the guide walls 2 and diffuse along the double-sided beveled edges. The diffusion guide walls 2 are single arcs, and the diffusion radius should not be too small to ensure that negative pressure does not occur on either side of the guide walls 2.

[0030] It should be noted that the designed lifting flow is the minimum discharge flow allowed when the spillway is working. During the design, it should be ensured that it can be discharged normally and will not hit the bank and cause negative effects.

[0031] In this embodiment, the double-sided bevel length refers to the planar length from the end of the diffuser guide wall 2 to the apex of the double-sided bevel, which should be no less than twice the width of the chute 1 to ensure sufficient longitudinal diffusion of the main flow. The double-sided bevel width refers to the transverse width of the diffuser guide wall 2 outlet section, which should be no more than twice the width of the chute 1 to control the transverse diffusion width of the water flow and ensure that the apex of the double-sided bevel maintains a constant water depth.

[0032] Specifically, during the design, the anti-arc bottom plate 3 of the double-sided beveled embankment adopts a single arc form, and the anti-arc radius is 4 to 10 times the water depth of the spillway 1. The specific optimization principle is to optimize the exit angle of the double-sided beveled vertex and the diversion ratio along the process under the premise that the position of the double-sided beveled vertex remains unchanged, so as to further improve the water inflow shape and energy dissipation and anti-impact indicators.

[0033] Combine Figure 1 As shown, the double-sided bevel apex is located at the foremost edge of the embankment 4, and the bottom must be located adjacent to the bedrock slope of the river channel or the upstream bedrock slope of the plunge pool. The double-sided bevel apex height refers to the height of the double-sided bevel apex from the lowest point of the anti-arc bottom plate 3, which is the maximum exit height that can still operate normally under the designed lifting flow. The double-sided bevel apex exit angle refers to the bottom plate angle at the double-sided bevel apex, which is used to control the water entry angle and longitudinal position at the water drop point, and is preferably 20-40 degrees.

[0034] In addition, the diversion ratio along the double-bevel cut is measured by the distribution of water depth along the double-bevel cut from the starting point to the vertex. Due to the outflow along the way, the water depth of the double-bevel cut decreases along the way. If the anti-arc radius is too small and the vertex of the double-side bevel cut is too high, the water depth at this place is less than 1m. Therefore, it is necessary to adopt a flat cut at the vertex, and the incision width is 0.1~0.3 times the width of the chute 1.

[0035] Specifically, the lateral position of the double-sided bevel vertex is defined by the lateral offset coefficient k, k=0~1. When k=0.5, it means that the double-sided bevel vertex is located on the center line of the chute 1. When k=0, it means that the double-sided bevel vertex is located on the guide wall 2 on the left side of the chute 1, and the plane shape is similar to the single-sided bevel step.

[0036] Specifically, the longitudinal length of the double-beveled vertex from the starting point is defined by the longitudinal stretch coefficient m, which ranges from 0 to 3. When m=2, the longitudinal length of the double-beveled apex is twice the width of the chute 1. When m=0, the double-beveled length is 0, and the outlet is a conventional diffusion sill.

[0037] The mathematical model during design consists of two parts. The first is to analyze the outflow shape of the cantilever during flood discharge, and optimize the parameters such as the diffusion radius of the cantilever guide wall 2, the width and length of the double-sided bevel, and the bottom plate anti-arc radius. The second part is to calculate the impact pressure of the water inflow on the bottom plate and bank slope of the downstream water cushion pond, as well as the river flow velocity distribution, after the cantilever body parameters are determined. The lateral position of the double-sided bevel vertices is adjusted.

[0038] Example 2 This embodiment provides a flood discharge structure, which is designed with a double-sided beveled embankment using the design method of Example 1. The double-sided beveled embankment is arranged in the flood discharge dam section of the power station dam, facing the downstream water cushion pond, and can also be arranged at the outlet of the flood discharge tunnel on the shore to connect with the downstream river channel.

[0039] The flood discharge structure adopts a double-sided beveled cantilever to fully stretch the flood discharge flow in the longitudinal direction, while controlling the water flow to moderately spread horizontally without damaging the slope protection on both sides, so that the energy dissipation index in the downstream water cushion pond reaches the optimal design method.

[0040] See also Figures 1 to 3 The chute 1 diffuses on the plane, with guide walls 2 on both sides and an anti-arc bottom plate 3 in the vertical direction to form a diversion flow. The outlet of the guide wall 2 is connected to the double-sided beveled diversion sill, which is located on the base 5. The water inflow pattern is changed by adjusting the double bevel width B, length L, anti-arc radius R, height H, and vertex position. The double bevel width B is the horizontal distance from the bevel starting point at the end of the guide wall 2, the double bevel length L is the longitudinal distance from the end of the guide wall 2 to the double-sided bevel vertex, and the double bevel height H is the distance from the double-sided bevel vertex to the lowest point of the chute 1 bottom plate. The double-sided bevel vertex is the intersection of the bevel edges on both sides. In order to prevent the water depth from being too small, the double-sided bevel vertex is usually cut flat. The incision width b, the horizontal position of the incision, and the height need to be determined through physical model tests. The double bevel width B and length L need to ensure that the downstream energy dissipation water body space is sufficient to accommodate the diffused water flow. The following design method is used: First, the width of the discharge channel 1 at the discharge tunnel outlet is B0 = 11m, the outlet water depth is h = 11m, and the outlet flow velocity is U = 30m / s. According to the formula: , calculate the minimum value of the radius R of the cambered bottom plate 3. In this embodiment, the cambered radius R of the cambered surface 6 is 80m, and the outlet plane initially adopts a single beveled diffusion camber. The specific shape is as follows Figure 4 As shown. The angle of the bevel plane is 45 degrees, the inner cantilever angle is 18 degrees, the height is H=3.7m, the outer cantilever angle is 43 degrees, and the height is H=21.2m. Downstream of the spillway is a water cushion pond. In order to make full use of the horizontal space, diffusion guide walls 2 are used on both sides of the cantilever. The diffusion radius r=350m, and the diffusion guide wall 2 extends to the end of the cantilever. Under the designed cantilever flow rate, the large bevel diffuser cannot be cantilevered in the area where the outlet position is higher and the flow velocity is lower, forming an oblique water jump flow state. Therefore, part of the bottom plate in the water jump area needs to be cut off together with the outer guide wall. Generally, the incision should be arranged along the water jump head. The water jump head refers to the area with high flow velocity and small water depth before the water jump occurs. The Froude number Fr>1 in this area.

[0041] Second, after cutting off the hydraulic jump part of the cantilever embankment outlet, the initial shape of the double-sided cantilever embankment is formed. The specific dimensions are as follows: Figure 5As shown in the figure, the total length of the diffusion guide wall 2 is 65.8m, the double bevel length L=13m, the starting width B=23.5m, and the outlet ejection angle is 18~28 degrees. Under the designed ejection flow, all water flows can be ejected. When the normal flow is designed, the water depth of the ejection bank increases sharply, the water tongue becomes thicker, and the water inflow is concentrated, resulting in a large impact pressure and flow rate at the bottom of the downstream water cushion pond. At the same time, the clean water body upstream of the water tongue inlet position does not participate in energy dissipation. Therefore, it is necessary to continue to move the starting point of the double-sided bevel upstream under the condition that the outlet elevation remains unchanged, so that part of the water flow is ejected in advance, so that the water body upstream of the water inlet point also participates in energy dissipation. For specific adjustment methods, see Figure 5 By continuously lengthening the bevels on both sides, the water flow's near-end water entry point is continuously retreated without hitting the bank slope. Thus, the diffusion guide wall 2 has a length of 52.5m, a double bevel length L=25m, a starting width B=19.0m, and an outlet projection angle of 8-28 degrees. Furthermore, considering that some flow is ejected in advance, which will reduce the outflow flow at the vertex of the double-sided bevels, the vertex is cut flat. Generally, the incision width b=(0.1-0.3)B, where B is the double bevel width, B=19m. In this embodiment, b=2m.

[0042] Third, the adjusted double-sided beveled embankment has a bevel length of L = 25m, a starting width of B = 19m, a vertex width of b = 2m, a longitudinal tensile coefficient of m = L / B = 1.315, and an exit angle of 8 to 27 degrees. In principle, the beveled vertices can be arranged symmetrically. In this embodiment, two spillways are used, limiting the lateral diffusion space on the outside. To prevent the floodwater from impacting the banks of the plunge pool and increasing the alongshore flow velocity, a sensitive analysis of the lateral position of the beveled vertices was performed using mathematical model analysis methods. Two body types were designed: Type I and Type II.

[0043] Type I: The apex of the bilaterally inclined slope is outward, and the lateral deviation coefficient k=0.273, that is, when the lateral width ratio is 3:8, the flow velocity in the impact zone of the water cushion pond guide wall is 15~20m / s; Type II: The apex of the bilaterally inclined slope is inward, and the lateral offset coefficient k=0.273, that is, when the lateral width ratio is 3:8, the flow velocity in the impact zone of the water cushion pond guide wall is reduced to 0~5m / s.

[0044] Therefore, the indicators of body type II are relatively good. The plane diagram of this body type is as follows: Figure 6 shown.

[0045] Example 3 This embodiment is a further optimization of embodiment 2. When the width of the downstream cushion pond bottom is significantly narrowed, in order to prevent the flood discharge from diffusing and impacting the slope protection on both sides of the cushion pond, the double-sided beveled bank in embodiment 2 and the outer diffusion-type guide wall 2 are changed to a straight guide wall 2. The guide wall 2 is 61.5m long and the bevel length is 19m. The inner diffusion-type guide wall 2 is 45.3m long and the bevel length is 35.2m. At the same time, the vertex position of the double-sided beveled bank in embodiment 2 is moved 7m outward, the lateral deflection coefficient k=0.09, and the lateral width ratio is 1:10. The specific style is as follows Figure 7 As shown, while maintaining the longitudinal diffusion of the water flow, the length of the outer guide wall 2 is adjusted to change the direction and shape of the water inflow, and limit the range of the water inflow impact zone to the width of the water cushion pond bottom plate.

[0046] Example 4 This embodiment is the application of Example 1 in the outlet embankment of the sand flushing bottom hole on the bank of the gravity dam project. The sand flushing bottom hole is arranged on the right bank. The lateral diffusion of the outlet water flow is restricted by the right bank slope. It is necessary to diffuse the water flow to the left side and at the same time stretch it longitudinally to reduce the scouring of the downstream river channel.

[0047] First, based on the bottom hole layout plan, the plan layout of the outlet embankment was determined. Due to the limited lateral space created by the right bank cofferdam during bottom hole construction, the diffusion radius of the left guide wall 2 was set at R = 300m. A straight wall + deflector was used on the right side. This ensured that the water flow primarily spread longitudinally, while also diffusing to the left to prevent it from impacting the right bank slope. The deflector is a wedge-shaped structure added to the vertical guide wall 2 of the embankment to deflect the water flow and adjust the lateral diffusion angle of the outlet water flow.

[0048] Second, determine the radius of the bottom arc of the embankment according to the use conditions of the bottom hole. During the construction and diversion of the sand flushing bottom hole, the water depth is 10m and the flow rate is 10m / s. According to the formula , the calculated reverse arc radius R>200m. In this embodiment, the bevel length L of the pick is relatively large. In order to reduce the outlet elevation of the bevel vertex and flush away all the sediment in the chute 1, the bottom arc radius takes a larger value, R=300m.

[0049] Third, the height of the bevel vertex is determined based on the radius of the bottom arc of the cantilever. Physical model testing determined that the maximum exit height H of the cantilever outlet vertex is 11.9 m. This ensures that during diversion and flood discharge construction, hydraulic jumps do not occur within the cantilever and that all water flows out. The two bottom-hole cantilever sills have the same bottom plate inflection radius, but different inflection starting points. The inflection starting point of the bottom plate of the right cantilever 8 is the same as the diffusion starting point of the guide wall 2, while the inflection starting point of the bottom plate of the left cantilever 7 is 35 m downstream of the diffusion point of the guide wall 2. This results in the exit elevation of the right cantilever 8 being 8 m higher than that of the left cantilever 7, which helps disperse the water flow and reduce downstream scour.

[0050] Fourth, determine the length and width of the bevel. Under the premise that the bevel vertex remains unchanged, extend the bevel edge upstream so that the water flow is pulled longitudinally upstream, while ensuring that the proximal water flow does not form local scouring under the embankment. Through optimization research, the shape of the embankment is obtained as follows: Figure 8 When a single boom is operating, the water flow is fully diffused. When two booms release water together, the water flows overlap in the air. The water flow at the right bottom hole is higher, while the water flow at the left bottom hole is lower, forming a dynamic water cushion to dissipate energy and reduce the depth of downstream scour.

[0051] Example 5 This embodiment provides a construction method for constructing the flood discharge structure in Example 2 using reinforced concrete.

[0052] The specific implementation methods described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific implementation method of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A design method for a double-sided beveled ridge, characterized in that: Including the following methods, S1. Design the shape of a single oblique diffuser sill and determine the hydraulic jump boundary line on the oblique diffuser sill based on the outlet hydraulic jump shape at the designed lift flow rate. S2. The bottom plate downstream of the hydraulic jump boundary line and the guide wall on the same side are removed to form a double-sided beveled overhang, and the double-sided beveled vertices of the double-sided beveled overhang correspond to the maximum exit height; S3. Under the premise that the position of the double-side bevel vertices remains unchanged, the bevel starting points on both sides are moved upstream to adjust the length of the double-side bevel; S4. Under the premise that the position of the double-sided bevel vertices remains unchanged, adjust the bottom plate anti-arc radius to change the water flow angle and the outflow ratio along the process. S5. According to the layout of the downstream plunge pond or the direction of the river, adjust the horizontal position of the bilateral bevel vertices to change the horizontal position of the water inflow.

2. The design method of double-sided beveled ridge according to claim 1, characterized in that: In step S1, the outlet angle of the single-bevel diffusion barrier is 10 degrees to 40 degrees, and the outlet height is 0m to 30m.

3. The design method of double-sided beveled ridge according to claim 2, characterized in that: In step S1, the plane cutting angle of the single-bevel diffusion barrier is 45±3 degrees.

4. The design method of double-sided beveled ridge according to claim 1, characterized in that: In step S3, the double-sided beveled length of the double-sided beveled ridge is not less than 2 times the groove width, and the transverse width of the double-sided beveled ridge does not exceed 2 times the groove width.

5. The design method of double-sided beveled ridge according to claim 4, characterized in that: In step S3, the double-sided bevel edges are located upstream of the hydraulic jump boundary.

6. A flood discharge structure, characterized in that: The double-sided beveled ridge is designed using the design method of the double-sided beveled ridge as claimed in claim 1.

7. The flood discharge structure according to claim 6, characterized in that: When there are two or more flood discharge structures and they are arranged in the center of the river channel or water cushion pond, the double-sided beveled embankments are arranged symmetrically, and the anti-arc curves of the embankment bottom plates are the same.

8. The flood discharge structure according to claim 6, characterized in that: When there are two or more flood discharge structures and they are arranged on the banks of rivers or water cushion ponds, the double-sided beveled embankments are arranged asymmetrically.

9. The flood discharge structure according to claim 8, characterized in that: By adjusting the starting point of the bottom plate anti-arc so that the inner sill is lower and the outer sill is higher, when multiple sills discharge water together, the water flow overlaps in the air, the water flow position of the outer sill is higher, and the water flow position of the inner sill is lower, forming a dynamic water cushion to dissipate energy.

10. A construction method, characterized in that: Construct a flood discharge structure as described in claim 6.

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