A composite section stilling pool

Abstract

The present invention discloses a composite cross-section energy dissipation pool, which belongs to the technical field of energy dissipation pool design. It can solve the problem that energy dissipation and sand / mud and rock flow discharge cannot be taken into account at the same time in the existing flood discharge and energy dissipation structure, and ice is easily formed at the outlet when operating at a small flow rate in winter, which endangers the safe operation of the flood discharge and energy dissipation structure. The energy dissipation pool includes: a pool body structure, including a bottom plate and side walls vertically connected to opposite ends of the bottom plate; a plurality of diversion and energy dissipation structures, which are distributed on the bottom plate in multiple rows along the direction of water flow, and each diversion and energy dissipation structure has a diversion surface and a water-blocking surface; the angle between the diversion surface and the corresponding side wall is an acute angle, which is used to guide the water flow to the middle of the bottom plate; the water-blocking surface is connected to the downstream end of the diversion surface, which is used to block water; the height of the water-blocking surface is higher than the height of the diversion surface; a rapids trough is opened in the middle of the bottom plate along the direction of water flow; and a plurality of diversion and energy dissipation structures are distributed on both sides of the rapids trough. The present invention is used for energy dissipation structures.

Description

Technical Field

[0001] The invention relates to a composite cross-section stilling pool, belonging to the technical field of stilling pool design. Background Art

[0002] In hydropower and water conservancy projects, bottom flow energy dissipation has become one of the most widely used energy dissipation types in the construction of water discharge structures due to its advantages such as high energy dissipation efficiency, stable inflow flow, small tailwater fluctuation, and small flood discharge atomization effect. The flood discharge energy dissipation structures supporting pumped storage projects and water conservancy and hydropower projects are often set up in narrow river valleys or natural channels. Due to the limitations of terrain conditions, the downstream energy dissipation pool usually needs to be dug down or energy dissipation sills are set up to raise the water level to produce a submerged water jump.

[0003] The flood discharge and energy dissipation structures supporting pumped storage projects and water conservancy and hydropower projects usually operate for a long time at a small flow rate, while taking into account the operation of large-flow flood discharge carrying silt / mudslides. However, the existing flood discharge and energy dissipation structures cannot take into account both energy dissipation and sand / mudslide discharge. The silt / mudslide carried by the downstream water flow is easy to accumulate in the energy dissipation pool, and the water flow swirls and wears the concrete of the energy dissipation pool when dissipating energy, making it difficult to ensure the safety and durability of the structure. With the continuous acceleration of the construction speed of pumped storage power stations, this problem has become more prominent. In addition, in cold and severely cold areas, the temperature is low in winter, the flood volume is small, and the flow rate is low. The flood discharge and energy dissipation structures supporting pumped storage projects and water conservancy and hydropower projects are prone to ice at the outlet, endangering the safe operation of the flood discharge and energy dissipation structures. Summary of the invention

[0004] The present invention provides a composite cross-section energy dissipation pool, which can solve the problem that energy dissipation and sand / mud and rock flow discharge cannot be taken into account simultaneously in the existing flood discharge and energy dissipation structure, and ice is easily formed at the outlet during low flow operation in winter, endangering the safe operation of the flood discharge and energy dissipation structure.

[0005] The present invention provides a composite section stilling pool, the stilling pool comprising:

[0006] A tank structure, comprising a bottom plate and side walls vertically connected to opposite ends of the bottom plate;

[0007] A plurality of diversion and force dissipation structures are arranged in multiple rows on the bottom plate along the water flow direction, each of the diversion and force dissipation structures has a diversion surface and a water-blocking surface; the angle between the diversion surface and the corresponding side wall is an acute angle, which is used to guide the water flow to the middle of the bottom plate; the water-blocking surface is connected to the downstream end of the diversion surface, which is used to block water; the height of the water-blocking surface is higher than the height of the diversion surface;

[0008] A rapids trough is provided in the middle of the bottom plate along the water flow direction; and a plurality of diversion and force dissipation structures are distributed on both sides of the rapids trough.

[0009] Optionally, the stilling pool further comprises:

[0010] The transition structure is arranged on the bottom plate of the water inlet end of the pool structure, and its downstream end is connected to the upstream end of the rapid flow trough, so as to guide the water flow into the rapid flow trough.

[0011] Optionally, the diversion and force dissipation structure includes:

[0012] The diversion pier has a horizontal cross section of a right triangle, one of the right-angled faces is in close contact with the corresponding side wall, and the inclined face is the diversion face;

[0013] The energy dissipation pier has a longitudinal section of a right-angled trapezoid, and its vertical side surface is closely connected to another right-angled surface of the diversion pier; the vertical side surface of the energy dissipation pier is the water-blocking surface.

[0014] Optionally, along the water flow direction, the heights of the multiple rows of guide piers gradually decrease.

[0015] Optionally, along the water flow direction, the angles between the diversion surfaces of the multiple rows of diversion piers and the corresponding side walls gradually increase.

[0016] Optionally, the bottom slope of the rapids trough is greater than or equal to 3%.

[0017] Optionally, two diversion and energy dissipation structures are provided in each row, and the two diversion and energy dissipation structures are distributed on both sides of the rapids trough and are closely attached to the side walls on the corresponding sides respectively.

[0018] Optionally, the transition structure is a transition curved surface.

[0019] Optionally, the bottom plate is a planar slope along the direction of water flow.

[0020] Optionally, the diversion and force dissipation structure is anchored on the base plate by anchoring steel bars.

[0021] The beneficial effects that the present invention can produce include:

[0022] The composite cross-section energy dissipation pool provided by the present invention utilizes the water retaining and water-blocking effects of the energy dissipation piers. When water flows in the energy dissipation pool, a sufficient and stable water jump is formed when the water flows encounter the energy dissipation piers. At the same time, the diversion piers on both sides generate counter-flow water flows. The water flows impact and collide to dissipate energy. After the water flows roll between multiple rows of energy dissipation piers to dissipate energy, it flows into the downstream river channel and will not cause destructive scouring to the downstream river channel. This greatly reduces the difficulty of protecting the downstream of the energy dissipation pool. Compared with the traditional down-dug energy dissipation pool and energy dissipation sill type energy dissipation pool, the energy dissipation pier, the diversion pier and the rapids trough in the present invention utilize the interval between the energy dissipation piers and the scouring effect of the water flow on the diversion piers on both sides. When the water flows downward, the silt and sediment in the energy dissipation pool can be washed downstream, and the silt will not accumulate in the energy dissipation pool, thereby reducing the wear of the silt on the concrete of the energy dissipation pool. The rapids trough can make the sediment source in the energy dissipation pool flush downstream with the water flow when the energy dissipation pool is running at a small flow rate, thereby reducing the number of inspections and desilting of the energy dissipation pool. In this way, the silt can be discharged smoothly under the premise of generating a stable water jump, and the problem of sedimentation in the energy dissipation pool caused by the sediment / mudslide carried by the downstream water flow of the pumped storage power station and the water conservancy and hydropower project is solved. At the same time, the rapids trough in the present invention is set so that when the energy dissipation pool is running at a small flow rate, the water flow enters the energy dissipation pool and flows into the rapids trough through the transition surface. Since the rapids trough has a small bottom width and a large slope, the flow rate in the rapids trough is relatively large, and it is not easy to produce ice when the energy dissipation pool is running at a small flow rate in winter. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 A schematic diagram of the three-dimensional structure of a composite cross-section stilling pool provided in an embodiment of the present invention;

[0024] Figure 2 A schematic diagram of a plan view of the structure of a composite cross-section stilling pool provided in an embodiment of the present invention;

[0025] Figure 3 for Figure 2 Schematic diagram of the cross-sectional structure in the AA direction;

[0026] Figure 4 for Figure 2 Schematic diagram of the cross-sectional structure in the middle BB direction;

[0027] Figure 5 for Figure 2 Schematic diagram of the cross-sectional structure in the CC direction;

[0028] Figure 6 for Figure 2 Schematic diagram of the cross-sectional structure in the middle DD direction;

[0029] Figure 7 A schematic diagram of a diversion and force dissipation structure provided in an embodiment of the present invention;

[0030] Figure 8 A schematic diagram of the bottom plate structure provided by an embodiment of the present invention;

[0031] Fig. 9A schematic diagram of the connection structure between the diversion and force dissipation structure and the base plate provided in an embodiment of the present invention.

[0032] Reference numerals:

[0033] 1. Bottom plate; 2. Side wall; 3. Diversion pier; 31. Diversion surface; 4. Energy dissipation pier; 41. Water-blocking surface; 5. Rapids trough; 6. Transition surface; 7. Anchor rod; 8. Keyway; 9. Seam reinforcement; 10. Waterstop; 11. Inserted reinforcement; 12. Anchor reinforcement; 13. Tooth groove; 14. Flow surface; 15. Connecting reinforcement. DETAILED DESCRIPTION

[0034] The present invention is described in detail below in conjunction with embodiments, but the present invention is not limited to these embodiments.

[0035] The embodiment of the present invention provides a composite section stilling pool, such as Figures 1 to 9 As shown, the energy dissipation pool includes:

[0036] The pool structure includes a bottom plate 1 and side walls 2 vertically connected to opposite ends of the bottom plate 1.

[0037] The bottom plate 1 is a rectangular or isosceles trapezoidal concrete structure, and the corresponding energy dissipation pool is a rectangular section or a rectangular diffusion section. Further, the bottom plate 1 can be set as a plane slope (the slope is generally less than 2%). In this example, the bottom plate 1 is set as a 1% plane slope along the water flow direction.

[0038] The downstream end of the bottom plate 1 is connected to the tooth groove 13 as a whole, and the left and right sides of the bottom plate 1 are connected to the side wall 2 as a whole.

[0039] A plurality of diversion and force dissipation structures are distributed in a plurality of rows on the bottom plate 1 along the direction of water flow, and each of the diversion and force dissipation structures has a diversion surface 31 and a water-blocking surface 41; the angle between the diversion surface 31 and the corresponding side wall 2 is an acute angle, which is used to guide the water flow and the sediment carried by the water flow to the middle part of the bottom plate 1; the water-blocking surface 41 is connected to the downstream end of the diversion surface 31, and is used to block water; the height of the water-blocking surface 41 is higher than the height of the diversion surface 31.

[0040] According to the flow rate of water flowing into the pool, multiple rows of diversion and energy dissipation structures can be arranged on the bottom plate 1, which can be arranged in parallel or in a staggered manner. In this example, a parallel arrangement is adopted, that is, two diversion and energy dissipation structures are arranged in each row, and the two diversion and energy dissipation structures are respectively close to the side wall 2 on the corresponding side. A certain distance should be left between the two diversion and energy dissipation structures in the same row to facilitate sand flushing during operation and silt removal during maintenance.

[0041] In the embodiment of the present invention, the diversion and force dissipation structure is anchored on the base plate 1 by anchoring steel bars 12 .

[0042] The above-mentioned diversion and force dissipation structure includes:

[0043] The diversion pier 3 has a horizontal cross section of a right triangle, one of the right-angled faces is in close contact with the corresponding side wall 2, and the inclined face is a diversion face 31;

[0044] The energy dissipation pier 4 has a longitudinal section of a right-angled trapezoid, and its vertical side surface is closely connected to another right-angled surface of the diversion pier 3; the vertical side surface of the energy dissipation pier 4 is a water-blocking surface 41.

[0045] Figure 1 The direction of the middle arrow is the direction of water flow, and the above longitudinal section is the section along the direction of water flow.

[0046] refer to Figure 7 As shown, the diversion and force dissipation structure is a reinforced concrete structure formed by combining the force dissipation pier 4 and the diversion pier 3.

[0047] The diversion pier 3 is a concrete structure with a right triangle horizontal section, which is anchored on the bottom plate 1 of the energy dissipation pool by anchoring steel bars 12. The height of the diversion pier 3 is generally less than that of the energy dissipation pier 4, and is used to change the flow direction of water flow, use water flow to flush sand, and play a role in discharging sand / mud and rock flow.

[0048] The energy dissipation pier 4 is a concrete structure with a straight wall (vertical flow surface) on the water-facing surface and a right-angle trapezoidal longitudinal section, which is anchored on the bottom plate 1 of the energy dissipation pool by anchoring steel bars 12. Through the water retaining and water-holding effects of the energy dissipation pier 4, the water flow rolls between multiple rows of energy dissipation piers 4 and then flows down.

[0049] The height of the stilling pier 4 is determined comprehensively according to the design working condition single width flow, water flow velocity, and Froude number, and is positively correlated with the single width flow, water flow velocity, and Froude number. The height of the diversion pier 3 is positively correlated with the multi-year average sediment content of the water flow through the pool, and the angle between the diversion surface 31 of the diversion pier 3 and the corresponding side wall 2 is negatively correlated with the multi-year average sediment content.

[0050] In the embodiment of the present invention, the heights of the multiple rows of guide piers 3 gradually decrease along the water flow direction, so as to obtain a better energy dissipation effect.

[0051] Furthermore, along the water flow direction, the angles between the guide surfaces 31 of the multiple rows of guide piers 3 and the corresponding side walls 2 gradually increase, which can achieve better energy dissipation and sand discharge effects.

[0052] The rapid flow trough 5 is provided in the middle of the bottom plate 1 along the water flow direction; a plurality of diversion and force dissipation structures are distributed on both sides of the rapid flow trough 5 .

[0053] A rapid flow groove 5 is arranged on the bottom plate 1, and the bottom slope of the rapid flow groove 5 needs to be greater than or equal to 3%. In practical applications, the bottom slope of the rapid flow groove 5 is 3% to 5%.

[0054] Furthermore, the stilling pool also includes:

[0055] The transition structure is arranged on the bottom plate 1 at the water inlet end of the pool structure, and its downstream end is connected to the upstream end of the rapid flow trough 5 for guiding the water flow into the rapid flow trough 5 .

[0056] In practical applications, the transition structure may be a transition curved surface 6 .

[0057] The water at the inlet of the stilling basin flows into the rapid flow trough 5 through the transition curved surface 6 , and then flows out through the downstream end of the rapid flow trough 5 .

[0058] In the embodiment of the present invention, reference Figure 8 As shown, when the bottom plate 1 of the energy dissipation pool is too long or too wide, a construction joint can be set, and a key groove 8 is arranged on the joint surface to increase the contact area. There are cross-joint steel bars 9 on the concrete structure surface of the bottom plate 1 and the side wall 2, and water stop 10 and dowel 11 are arranged on the construction joint.

[0059] refer to Fig. 9 As shown, after the foundation excavation is completed, holes are drilled in the bedrock, steel bars are arranged, and cement mortar is poured to form anchors, which usually penetrate 4m to 6m into the rock mass; one end of the connecting steel bar 15 is welded to the exposed end of the anchor rod 7, and the other end of the connecting steel bar 15 is welded to the steel mesh on the flow surface 14 of the bottom plate 1. The anchor rods 7 are arranged in a plum blossom or grid shape on the concrete bottom plate 1. The diversion pier 3 and the energy dissipation pier 4 are connected to the bottom plate 1 as a whole through the anchor steel bar 12.

[0060] Usually, the sand content and the proportion of large-size sources in floods, especially mountain torrents, are positively correlated with the flood volume, and the flood volume is positively correlated with the flow rate. The energy dissipation pool described in this embodiment utilizes the water-blocking and water-blocking effects of the energy dissipation pier 4 when the flow is large, produces a stable water jump, reduces the flow rate, and ensures that no scouring damage is caused to the downstream river channel when the flood is discharged. At the same time, the diversion, sand-blocking and sand-washing effects of the diversion pier 3 and the rapids trough 5 are utilized. When the water flows downward, the silt and sedimentary materials in the energy dissipation pool can be washed downstream, reducing the wear of the silt on the concrete of the energy dissipation pool. When the flow is small, the water flows through the transition surface 6 and enters the rapids trough 5 with a steeper slope. The existence of the rapids trough 5 can ensure that a certain flow rate is maintained at a small flow rate, and the sedimentary sources in the energy dissipation pool can be washed downstream at a small flow rate and when floods are often encountered, reducing silt removal. At the same time, when the slope of the rapids trough 5 is greater than 3%, the flow rate in the rapids trough 5 can make it less likely to produce ice at low temperatures compared to traditional energy dissipation pools. The present invention fully takes into account the requirements of flood discharge, energy dissipation, sand removal and anti-freezing, and is worthy of being promoted in flood discharge and diversion buildings and flow in pumped storage projects and water conservancy and hydropower projects.

[0061] In practical application, the construction method of the above-mentioned pool structure includes the following steps:

[0062] (1) Foundation construction, the foundation of which is bedrock. The tooth groove 13 and the bottom plate 1 (or the bottom plate 1 and the side wall 2) are excavated according to the designed body shape. After the excavation is completed, holes are drilled in the rock, anchor rods 7 are installed, and grouting of the anchor rods 7 is completed;

[0063] (2) After the anchor rod 7 is constructed, one end of the connecting steel bar 15 is welded to the exposed anchor rod 7, and the other end is welded to the steel mesh of the flow surface 14 of the bottom plate 1;

[0064] (3) Steel bar installation: steel bars are manufactured and installed according to the steel bar diameter and spacing required by the design, and cross-joint steel bars are arranged at the construction joints 9;

[0065] (4) According to the requirements of the design drawings and the construction organization, install water stop 10 and dowel 11 at the construction joints of the concrete of the bottom plate 1 and the side wall 2;

[0066] (5) When pouring concrete, the bottom plate 1 should be poured first, and then the 1.5m / 1.0m side wall 2 should be poured together. If the flow surface 14 of the bottom plate 1 and the force dissipation pier 4 are made of impact-resistant and wear-resistant concrete, they should be poured together to ensure that the flatness of the bottom plate 1 and the side wall 2 meets the requirements of the design drawings and specifications.

[0067] If the tooth groove 13 needs to be provided with anchoring measures, after the foundation surface is excavated, it is paralleled with the anchoring measures of the bottom plate 1. At the same time, the foundation can be covered and consolidated with heavy grouting according to the bedrock conditions of the bottom plate 1.

[0068] The composite cross-section energy dissipation pool provided by the present invention makes full use of the water retaining and water-blocking effects of the energy dissipation pier 4, so that the water flow generates a sufficient and stable hydraulic jump upstream of the energy dissipation pier 4, avoiding the generation of a wavy hydraulic jump with almost no energy dissipation effect when the water flow is discharged. The present invention improves the phenomenon of the foundation of the flood discharge structure and the hub bank slope being damaged by the water flow by reducing the water flow velocity, and greatly reduces the downstream protection pressure.

[0069] The composite cross-section energy dissipation pool provided by the present invention makes full use of the diversion, sand interception and sand flushing functions of the diversion piers 3 and the rapids troughs 5. The diversion piers 3 on both sides generate counter-flow water flow, and the water flow impacts and collides to dissipate energy. At the same time, the water flow on both sides flushes the diversion piers 3, and the silt is not easy to accumulate, and is discharged smoothly along the gaps between the energy dissipation piers 4 along the mainstream. In addition, the rapids troughs 5 can enable the silt source in the energy dissipation pool to be flushed to the downstream in small flow and frequent floods, reducing dredging. The gap between the diversion and energy dissipation structures should be based on the principle of ensuring that the downstream water flow does not damage the foundation of the flood discharge building and the hub bank slope by the water flow, and at the same time should be greater than the minimum distance for the dredging vehicle to pass.

[0070] The composite cross-section energy dissipation pool provided by the present invention fully utilizes the flow capacity of the rapids trough 5. After water flows into the energy dissipation pool, it flows into the rapids trough 5 through the transition surface 6. Since the rapids trough 5 has a small bottom width and a large slope, when the flood discharge and energy dissipation structure operates at a small flow rate in winter, the flow velocity in the rapids trough 5 is relatively large, and ice is not easily generated in the energy dissipation pool.

[0071] The composite section stilling pool provided by the present invention is particularly suitable for small single width flow (single width flow less than 20m 3 / s), in discharge projects with medium and low Froude numbers.

[0072] The above are only a few embodiments of the present application and do not constitute any form of limitation to the present application. Although the present application is disclosed as above with preferred embodiments, it is not intended to limit the present application. Any technician familiar with the profession, without departing from the scope of the technical solution of the present application, using the technical content disclosed above to make slight changes or modifications are equivalent to equivalent implementation cases and fall within the scope of the technical solution.

Claims

1. A composite section stilling pool, characterized in that: The stilling pool comprises: A tank structure, comprising a bottom plate and side walls vertically connected to opposite ends of the bottom plate; A plurality of diversion and force dissipation structures are arranged in multiple rows on the bottom plate along the water flow direction, each of the diversion and force dissipation structures has a diversion surface and a water-blocking surface; the angle between the diversion surface and the corresponding side wall is an acute angle, which is used to guide the water flow to the middle of the bottom plate; the water-blocking surface is connected to the downstream end of the diversion surface, which is used to block water; the height of the water-blocking surface is higher than the height of the diversion surface; A rapids trough is provided in the middle of the bottom plate along the water flow direction; a plurality of diversion and force dissipation structures are distributed on both sides of the rapids trough; The diversion and force dissipation structure comprises: The diversion pier has a horizontal cross section of a right triangle, one of the right-angled faces is in close contact with the corresponding side wall, and the inclined face is the diversion face; The energy dissipation pier has a longitudinal section of a right-angled trapezoid, and its vertical side surface is closely connected to another right-angled surface of the diversion pier; the vertical side surface of the energy dissipation pier is the water-blocking surface.

2. The energy dissipation pool according to claim 1, characterized in that: The stilling pool also includes: The transition structure is arranged on the bottom plate of the water inlet end of the pool structure, and its downstream end is connected to the upstream end of the rapid flow trough, so as to guide the water flow into the rapid flow trough.

3. The energy dissipation basin according to claim 1, characterized in that: Along the direction of water flow, the heights of multiple rows of diversion piers gradually decrease.

4. The energy dissipation basin according to claim 1 or 3, characterized in that: Along the water flow direction, the angles between the diversion surfaces of multiple rows of diversion piers and the corresponding side walls gradually increase.

5. The energy dissipation basin according to claim 1, characterized in that: The bottom slope of the rapids trough is greater than or equal to 3%.

6. The energy dissipation basin according to claim 1, characterized in that: Two diversion and energy dissipation structures are arranged in each row. The two diversion and energy dissipation structures are distributed on both sides of the rapids trough and are closely attached to the side walls on the corresponding sides respectively.

7. The energy dissipation basin according to claim 2, characterized in that: The transition structure is a transition curved surface.

8. The stilling basin according to claim 1, characterized in that: The bottom plate is a plane slope along the water flow direction.

9. The energy dissipation basin according to claim 1, characterized in that: The diversion and force dissipation structure is anchored on the bottom plate through anchoring steel bars.

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