Reservoir emptying pipeline canal entering system and method

Abstract

The invention belongs to a channel entering structure in the technical field of reservoir emptying, and particularly relates to a channel entering system and method for a reservoir emptying pipeline. The system comprises a water conveying channel, an overflow well is arranged on one side of the water conveying channel, and an emptying pipeline is connected to one side of the overflow well; the top of the water conveying channel is provided with a water passing section corresponding to the overflow well; an overflow opening is formed in the side, facing the water passing section, of the overflow well and used for controlling the overflow flow of water. Water flowing out of the overflow port passes through the water section to form runoff; the runoff is attached to the slope surface of the water conveying channel and slowly enters the channel through the water passing section. After the emptying pipeline passes through the overflow well, water flow energy of the emptying pipeline can be eliminated, then overflow is carried out through the overflow port, the overflow port is connected with a water passing road surface, water flow is smoothly guided into a channel, and the channel side slope is prevented from being scoured.

Description

Technical Field

[0003] The invention belongs to a channel inlet structure in the technical field of reservoir emptying, and in particular relates to a reservoir emptying pipeline channel inlet system and method. Background Art

[0005] During the operation of the reservoir, when cracks appear in the dam body, leakage around the dam, etc., it is necessary to drain a certain amount of storage capacity and then deal with the dam in a targeted manner. Therefore, it is necessary to set up a draining pipe at a position 2 to 6 meters lower than the dam elevation to drain the storage capacity, and the pipe diameter is determined according to the draining time required by the reservoir.

[0006] See also Figure 1 As shown, the vent pipe is connected to the downstream channel through a pipeline. In order to dissipate energy, an energy dissipation valve well is set at the connection between the pipeline and the vent pipe. However, due to the pressure inside the pipeline, when water is suddenly released from the end of the pipeline, it will spray out at a high speed. This high kinetic energy water flow will cause a considerable impact on the slope of the channel; see Figure 2 As shown in Figure 2, when water flows at a large angle and hits the channel slope, most of the kinetic energy it carries is used to counteract the friction and other resistance between soil particles, causing these particles to break away from their original positions and be carried away by the water flow, causing scouring damage to the slope.

[0007] Patent publication number CN205576835U discloses a multi-stage self-collapsing earth flood diversion dam protected by geosynthetics, see Figure 3 As shown, two parallel trenches are opened downstream of the dam, the parallel trenches are the first trench 18-1 and the second trench 18-3, and a road 18-4 is set between the first trench 18-1 and the second trench 18-3 to further dissipate energy and prevent erosion by using the trench road.

[0008] It can be seen that it is urgent to propose a reservoir emptying pipeline into the canal system that can use the road to pass water. Summary of the invention

[0010] Based on the above background, since the amount of water flowing through the reservoir is much smaller than that of flood diversion, and the location of the water outflow is fixed, the following problems arise:

[0011] The water will flow directly along the ditch and will not flow through the road surface to reach the canal;

[0012] It is difficult for water to form runoff on the road, resulting in large areas of water accumulation on the road;

[0013] The height of water flow on the road surface cannot be controlled, which brings uncertain risks to road traffic.

[0014] In order to solve the above problems, the present invention provides a reservoir emptying pipe inlet channel system, which includes a water conveyance channel, an overflow well is arranged on one side of the water conveyance channel, and an emptying pipe is connected to one side of the overflow well;

[0015] A water-passing section is provided on the top of the water delivery channel corresponding to the overflow well;

[0016] The overflow well is provided with an overflow port on one side facing the water flow section, and the overflow port is used to control the overflow flow of water;

[0017] Wherein, the water flowing out of the overflow port forms runoff through the water section;

[0018] The water-passing section allows the runoff to follow the slope of the water conveyance channel and flow into the channel slowly.

[0019] First, preliminary energy dissipation is carried out through the overflow well. After energy dissipation, the overflow flow of water is controlled through the overflow port to avoid water accumulation in the water-passing section and limit the water-passing height to ensure the safety of vehicle passage. In addition, the water flowing out through the rectangular overflow port has an increased linear length, which means that the water flow is dispersed, reducing the water flow energy density per unit area. The treated water flow is gentler, reducing the risk of erosion to downstream channels and slopes.

[0020] Secondly, the runoff on the water-passing section is spread out, and the spread runoff will slowly enter the channel along the slope of the water transfer channel. In this way, the runoff can contact the slope at a smaller angle rather than impact vertically, and the direct impact force of the water flow on the slope will be greatly reduced. This design reduces the direct destructive effects of water flow velocity and kinetic energy on the slope, and helps reduce the risk of soil particles being carried away by water. By allowing the runoff to spread out and flow along the slope, the contact area between the water flow and the slope is increased, which not only reduces the water flow energy density per unit area, but also extends the length of the water flow path on the slope, which is conducive to further dispersing the energy of the water flow and reducing its erosion ability on the slope.

[0021] Moreover, by adjusting the angle of the runoff into the channel, the water can flow more smoothly along the slope, which can effectively reduce the formation of turbulence and eddies, thereby alleviating damage to the slope.

[0022] As a further improvement of the technical solution, the water-passing section is paved with drainage boards; specifically, the water-passing section is a water-passing structure with high sides and low middle, thereby obtaining a first side slope and a second side slope.

[0023] In one technical solution: the cross-sections of the first side slope and the second side slope are both isosceles triangles;

[0024] The first side slope and the second side slope are arranged on the top of the water conveyance channel.

[0025] In another technical solution: a groove is dug on the top of the water conveyance channel on one side facing the overflow well;

[0026] A first side slope and a second side slope are respectively arranged on both sides of the groove;

[0027] The cross-sections of the first side slope and the second side slope are right triangles.

[0028] Furthermore, the top of the water conveyance channel is lifted upward;

[0029] The bottom surface of the trough is flush with the upper edge of the water delivery channel.

[0030] Alternatively, a trapezoidal notch is provided on one side where the water conveyance channel is connected to the water-passing section;

[0031] The notch is connected to the water-passing section.

[0032] Preferably, the slope ratio of the first side slope to the second side slope is 1:8.

[0033] In terms of water flow, a slope ratio of 1:8 can form a longer water flow section and increase the water flow area. At the same time, a gentle slope may reduce the water flow speed and reduce erosion. Because the water needs to be guided to the opposite channel, a certain slope is required to ensure the direction of the water flow, and 1:8 is gentle enough to allow water to flow naturally without being too fast, thereby reducing scour.

[0034] In addition, gentle slopes have less impact on tires, allowing vehicles to pass more smoothly, especially for large vehicles or vehicles traveling at high speeds, reducing the risk of loss of control.

[0035] As a further improvement of the technical solution, the top of the water conveyance channel is a paved maintenance road;

[0036] A plate is built on the water-passing section, and the plate is used for vehicles to pass through;

[0037] The two ends of the plate are arranged at an oblique angle, and the oblique angle is adapted to the inclination angles of the first side slope and the second side slope.

[0038] In this solution, the 1:8 gentle slope makes the contact area between the plate and the slope larger, the force is more evenly distributed, the local stress concentration is reduced, and the risk of plate deformation or damage is reduced; because the two ends of the plate are supported on the gentle slope, the mid-span deflection of the plate is small, which can better withstand vehicle loads. Even force distribution and reduced deflection can effectively extend the service life of the plate.

[0039] A method for the above-mentioned reservoir emptying pipeline into the canal system is also provided, which comprises the following steps:

[0040] S1, water flows into the overflow well through the vent pipe;

[0041] S2, the water in the overflow well flows out through the overflow port;

[0042] Then, it passes through the water-passing section to form runoff and flows into the water transfer channel.

[0043] Compared with the prior art, the present invention has the following beneficial effects:

[0044] In the reservoir emptying pipe entering the channel system and method, after the emptying pipe passes through the overflow well, the water flow energy of the emptying pipe can be eliminated and then overflowed through the overflow port, and the overflow port is connected to the water road surface to smoothly guide the water flow into the channel to avoid scouring the channel slope. In addition to ensuring that the water flows smoothly into the channel, the water road surface can also provide a good driving experience without damaging the channel embankment road, and can eliminate the adverse effects of water accumulation on the road surface on driving, thereby improving driving stability. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] Figure 1 It is a schematic diagram of the plan layout of the water discharge structure of the present invention;

[0047] Figure 2 This is a schematic diagram of the water discharge structure at the end of the pipeline;

[0048] Figure 3 It is a schematic diagram of the structure of parallel grooves;

[0049] Figure 4 It is a schematic diagram of the plan layout of the vent pipeline end entering the channel of the first embodiment;

[0050] Figure 5 This is a schematic diagram of the vent pipeline entering the channel structure of the first embodiment;

[0051] Figure 6 The second schematic diagram of the venting pipeline entering the channel structure of the first embodiment;

[0052] Figure 7 It is a schematic diagram of the cross-sectional structure of the venting pipeline entering the channel of the first embodiment;

[0053] Figure 8 It is a schematic diagram of the structure of a venting pipeline with a venting pipe according to the second embodiment;

[0054] Fig. 9 It is a schematic diagram of the venting pipeline entering the channel structure of the second embodiment;

[0055] Fig.10 It is a schematic diagram of the venting pipeline entering the channel structure of the third embodiment;

[0056] Fig.11 This is a schematic diagram of the structure of a venting pipeline with a plate material according to the fourth embodiment. DETAILED DESCRIPTION

[0058] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0059] To solve the problem that water cannot form controllable runoff on the road.

[0060] See also Figure 4 and Figure 5 As shown, the first embodiment proposes a reservoir emptying pipeline into the canal system, in which drainage boards are laid on the maintenance road 200 laid on the canal top to drain the accumulated water from the road surface. These drainage boards are set on the surface of the road surface, and the road surface forms a "floating" water-passing section 230 (water-passing structure) with high sides and low middle, which can quickly form runoff to flow into the water conveyance channel 100. The water conveyance channel 100 is a channel for carrying the reservoir to be emptied. The high positions on both sides form slopes 210 and 220 with a slope ratio of 1:8. The slopes 210 and 220 form enclosures. The slopes 210 and 220 are respectively connected to the roads 201 and 202 on both sides to ensure that vehicles can pass smoothly and maintain the stability and safety of the road.

[0061] Among them, Figure 5 As shown, the cross-section of the first side slope 210 and the second side slope 220 is an isosceles triangle structure. The first side slope 210 and the second side slope 220 laid on the maintenance road 200 form two steep slopes respectively. The two steep slopes are spaced a certain distance apart, and the slope ratios of the slopes on both sides of the steep slopes are both 1:8. The runoff formed by water flowing between the two steep slopes is perpendicular to the road line of the maintenance road 200, so that it can flow into the water transfer channel 100 in a concentrated manner.

[0062] Specifically, at least one vent pipe 400 is laid to the water delivery channel 100, such as Figure 4 As shown, an energy dissipation valve well is constructed near the water delivery channel 100, and then a section of venting pipe 400 parallel to the water delivery channel 100 is connected under the support of the anchor pier, wherein the anchor pier is equipped with surface steel bars, the steel bars are HPB300, the diameter is 10mm, and the spacing is 200mm, the venting pipe 400 is made of Q345C steel, and the inner wall of the steel pipe is anticorrosive (the bottom layer is 60μm thick epoxy zinc-rich paint; the middle layer is 80μm thick epoxy micaceous iron intermediate paint; the surface layer is 120μm thick water tank paint). The anti-corrosion bottom layer of the steel pipe outer wall is 160μm thick; the middle layer is 120μm thick of special epoxy sealing paint; the surface layer is 120μm thick of modified epoxy paint.

[0063] It should be noted that the venting pipeline 400 is buried underground, and the trench backfill is made of excavated materials. Before the pipeline is backfilled, plant roots and humus must be removed to a depth of about 0.5m. It is strictly forbidden to backfill the trench with covering layers and organic humus. Other backfill requirements are as follows:

[0064] (1) Cushion: A medium or coarse sand cushion is set at the bottom of the pipeline, with a compaction degree ≥ 90% and Dr ≥ 0.75;

[0065] (2) Manual backfilling of the 120cm area of ​​the pipe base: backfilling both sides of the medium and coarse sand evenly at the same time without disturbing the pipe position, with a compaction degree of ≥95% and Dr ≥0.75;

[0066] (3) Manual backfilling from 120 cm from the pipe base to the pipe top: Use the excavated material to backfill evenly along both sides of the pipe at the same time to ensure that the pipe position is not disturbed, with a compaction degree of ≥95%, Dr ≥0.75, and a particle size requirement of ≤40 mm;

[0067] (4) Artificial backfill from the top of the pipe to 80 cm from the top of the pipe: use excavated materials, compaction degree ≥ 90%, Dr ≥ 0.7, and particle size requirement ≤ 40 mm;

[0068] (5) Mechanical compaction backfill from 80 cm to 130 cm from the top of the pipe: using excavated materials, compaction degree ≥ 90%, Dr ≥ 0.7;

[0069] (6) Mechanical backfilling above 130 cm from the top of the pipe: backfill to the original ground;

[0070] (7) Backfill from the bottom of the trench to 80 cm above the top of the pipe should not contain large rocks, other sharp lumps, tree roots, branches, weeds and other organic matter.

[0071] In addition, heavy machinery vibration and rolling are not allowed above the top of the pipe. For the surface layer within 1m thick of the cultivated land section, the original excavated cultivated soil is used for backfilling without compaction.

[0072] The above trench excavation, backfilling and pipeline installation construction should be carried out in accordance with the "Code for Construction and Acceptance of Water Supply and Drainage Pipeline Projects" (GB 50268-2008).

[0073] In addition, if Figure 5 As shown, the water conveyance channel 100 is accompanied by a maintenance road 200, which is also used to meet the channel top width required for channel slope stability.

[0074] like Figure 5As shown, an overflow well 300 is built at the end of the drain pipe 400, and an overflow port 310 is provided on the overflow well 300. When building, the overflow port 310 is close to one side of the water-passing section 230, and then the drain pipe 400 is connected to the overflow well 300 to realize water inflow from top to bottom, and then flows out from the overflow port 310 through the water-passing section 230 to form runoff, and then flows into the water conveyance channel 100.

[0075] See also Figure 6 As shown, the specific process of the above-mentioned channel entry method is as follows:

[0076] S1, water flows into the overflow well 300 through the vent pipe 400;

[0077] S2, the water in the overflow well 300 flows out through the overflow port 310;

[0078] Then, the water passes through the water-passing section 230 to form runoff and flows into the water conveyance channel 100 .

[0079] The overflow well 300 is provided to prevent the water from the vent pipe 400 from directly flowing into the water delivery channel 100 (i.e. Figure 2 As shown in FIG. 3 ), the channel is scoured and damaged, and the energy is dissipated through the overflow well 300. The overflow well 300 is provided with an overflow port 310. The overflow port 310 can be calculated according to the wide top weir flow. The overflow capacity of the overflow port 310 can be calculated by the following formula:

[0080] (1)

[0081] in:

[0082] is the overflow flow; is the flow coefficient, and its value is between 0.235 and 0.303; l is the total width of the overflow port 310; is the acceleration due to gravity, which is 9.81m / s²; It is the water head above the weir.

[0083] Based on the above calculation formula, see Figure 7 As shown in the figure:

[0084] The height H0 refers to the vertical height from the bottom of the overflow port 310 to the lowest point of the water-passing section 230 (i.e., the entrance of the water delivery channel 100);

[0085] The height Hp refers to the vertical height from the top of the slopes 210, 220 to the lowest point of the water-passing section 230 (ie, the total vertical height of the slopes 210, 220).

[0086] H0≤Hp, that is, the overflow port 310 must be lower than or flush with the top of the slopes 210 , 220 , to ensure that after the water flows out of the overflow port 310 , it will not overflow the top of the slopes 210 , 220 and flood the roads 201 , 202 .

[0087] The slope ratio of the side slopes 210 and 220 is 1:8, the width of the water-passing section 230 is B, and the width of the overflow port 310 is l, then:

[0088] Hp = (Bl) / 2 × 1 / 8;

[0089] H0=Hp−ΔH;

[0090] Wherein, ΔH is the reserved safety height from the top of the overflow port 310 to the top of the slopes 210 and 220 (usually ≥ 0.1 m).

[0091] Next, control the water flow rate within the range of 0.5~2m / s to avoid scouring or siltation.

[0092] The width of overflow 310 is 2m, and the water head above the weir is is 0.4m, flow coefficient is 0.25; the width of the water-passing section 230 is 4 m, and the slope height Hp=B / 2×1 / 8=0.25m.

[0093] According to formula (1), we can get:

[0094] .

[0095] The water-passing section 230 is a trapezoidal section with a bottom width of B=4m. The water depth h is equal to the water head height above the weir, i.e. h=0.4m. The water-passing section area A=B×h+2×(1 / 2×8h×h)=4×0.4+8×0.4×0.4=2.4+1.28=2.88m²;

[0096] Slope correction for flow velocity:

[0097] The Manning formula is used to correct the flow velocity (assuming the roughness n=0.015), that is:

[0098] ;

[0099] in, is the flow rate; is the hydraulic radius, , wet week , then R≈0.276m; is the slope ratio.

[0100] get:

[0101] .

[0102] Through the height of the overflow port 310 (controlling the water head above the weir) and the slope of the water-passing section 230 (S=1:8), the water flow velocity is controlled at 1.2 m / s, meeting the anti-scouring requirement (<2 m / s).

[0103] In addition, the top height of the overflow port 310 is H0=Hp−0.1=0.25−0.1=0.15 m, so the maximum allowable water depth is Hmax=H0=0.15 m. The drainage capacity of the water-passing section is calculated as follows:

[0104] A´=4×0.15+8×0.15×0.15=0.6+0.18=0.78m²;

[0105] Qdrain=A´×v=0.78×1.2≈0.94 m³ / s;

[0106] Among them, Qdrain is the drainage capacity.

[0107] The overflow port 310 has a flow rate of 0.42 m³ / s, which is less than the drainage capacity of 0.94 m³ / s, so no water will accumulate.

[0108] For further information, see Figure 8 As shown, a drain pipe 320 is laid between the overflow well 300 and the water conveyance channel 100 and near the bottom surface of the overflow well 300 , and its main function is to drain the water in the overflow well 300 ; preferably, the drain pipe 320 is 1 / 8 to 1 / 10 of the diameter of the drain pipe 400 .

[0109] Second embodiment, see Fig. 9 As shown, when paving the inspection road 200 , the road surface of the inspection road 200 is raised by 0.1 m, and then a 0.1 m deep groove is dug on the side opposite to the overflow well 300 , and the bottom surface of the groove is flush with the upper edge of the water conveyance channel 100 .

[0110] In addition, side slopes 210, 220 with right triangle cross-sections are respectively arranged at the positions where the groove connects with the roads 201, 202, and the base length of the side slopes 210, 220 is 0.8m, so that the side slopes 210, 220 with a slope ratio of 1:8 are obtained.

[0111] In this embodiment, the method of entering the canal is also to lay drainage boards on the maintenance road 200 laid on the top of the canal to drain the accumulated water from the road surface. These drainage boards are set on the surface of the road surface, and the road surface forms a "sunken" water-passing section 230 with high sides and low in the middle.

[0112] The third embodiment, see Fig.10As shown, when the maintenance road 200 is paved, the road surface is flush with the upper edge of the water delivery channel 100 and no lifting treatment is performed; a 0.1m deep groove is dug on the side opposite to the overflow well 300, and slopes 210, 220 with right-angled triangle cross-sections are respectively arranged at the positions connecting the roads 201, 202 in the groove, and the bottom side length of the slopes 210, 220 is 0.8m, thereby obtaining slopes 210, 220 with a slope ratio of 1:8.

[0113] In addition, a trapezoidal notch is provided on one side of the water conveyance channel 100 where it is connected to the water passing section 230 , and the notch is connected to the water passing section 230 .

[0114] In this embodiment, the method of entering the canal is also to lay drainage boards on the maintenance road 200 laid on the top of the canal to drain the accumulated water from the road surface. These drainage boards are set on the surface of the road surface, and the road surface forms a "sunken" water-passing section 230 with high sides and low in the middle.

[0115] Fourth embodiment, see Fig.11 As shown, this embodiment is implemented on the basis of the second and third embodiments, and a vehicle-passing plate 203 (a plate for vehicles to pass) such as a steel plate or a concrete plate is built on the water-passing section 230, but the plate 203 will not affect the formation of runoff at the water-passing section 230 at its bottom; both ends of the plate 203 are set at an angle, and the angle is adapted to the inclination of the slopes 210 and 220, so that the plate 203 built on the water-passing section 230 can be connected to the roads 201 and 202 and be flush with the road surface.

[0116] The above shows and describes the basic principles, main features and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited by the above embodiments. The above embodiments and descriptions are only preferred examples of the present invention and are not intended to limit the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, which fall within the scope of the present invention. The scope of protection of the present invention is defined by the attached claims and their equivalents.

Claims

1. A reservoir emptying pipe inlet channel system, comprising a water delivery channel (100), characterized in that: An overflow well (300) is provided on one side of the water delivery channel (100), and a venting pipe (400) is connected to one side of the overflow well (300); A water-passing section (230) is provided on the top of the water delivery channel (100) corresponding to the overflow well (300); The overflow well (300) is provided with an overflow port (310) on a side facing the water flow section (230), and the overflow port (310) is used to control the overflow flow rate of water; The water flowing out of the overflow port (310) passes through the water section (230) to form runoff; The water-passing section (230) allows the runoff to follow the slope of the water conveyance channel (100) and flow slowly into the channel.

2. The reservoir emptying pipe inlet channel system according to claim 1, characterized in that: The water-passing section (230) is formed by paving a drainage board.

3. The reservoir emptying pipe inlet channel system according to claim 2, characterized in that: The water-passing section (230) is a water-passing structure with high sides and low middle, thereby obtaining a first side slope (210) and a second side slope (220).

4. The reservoir emptying pipe inlet channel system according to claim 3, characterized in that: The cross-sections of the first side slope (210) and the second side slope (220) are both isosceles triangles; The first side slope (210) and the second side slope (220) are arranged on the top of the water conveyance channel (100).

5. The reservoir emptying pipe inlet channel system according to claim 3, characterized in that: A groove is dug on the top of the water delivery channel (100) on the side facing the overflow well (300); A first side slope (210) and a second side slope (220) are respectively arranged on both sides of the groove; The cross-sections of the first side slope (210) and the second side slope (220) are right triangles.

6. The reservoir emptying pipe inlet channel system according to claim 5, characterized in that: The top of the water conveyance channel (100) is lifted upward; The bottom surface of the groove is flush with the upper edge of the water delivery channel (100).

7. The reservoir emptying pipe inlet channel system according to claim 5, characterized in that: A trapezoidal notch is provided on one side of the water conveyance channel (100) where it connects with the water passing section (230); The notch is connected to the water passing section (230).

8. The reservoir emptying pipe inlet channel system according to any one of claims 3 to 7, characterized in that: The slope ratio between the first side slope (210) and the second side slope (220) is 1:

8.

9. The reservoir emptying pipe inlet channel system according to claim 8, characterized in that: The top of the water conveyance channel (100) is a paved maintenance road (200); A plate (203) is built on the water-passing section (230), and the plate (203) is used for vehicles to pass through; Both ends of the plate (203) are arranged at an oblique angle, and the oblique angle is adapted to the inclination angles of the first side slope (210) and the second side slope (220).

10. A method for the reservoir emptying pipeline into the canal system according to claim 1, characterized in that: It includes the following steps: S1, water flows into the overflow well (300) through the vent pipe (400); S2, the water in the overflow well (300) flows out through the overflow port (310); Then, after passing through the water-passing section (230) to form runoff, it flows into the water conveyance channel (100).

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