Head hub structure suitable for deep and thick covering layer river reach diversion type power station
By designing the first hub structure in the deep covered river section, including the water inlet pool and trapezoidal dark dam, the problems of basic treatment and flood discharge and energy removal in the development of water diversion power stations are solved, and the coordination of simplified design and ecological protection is achieved, and the technical and economic feasibility is good.
Patent Information
- Application Number
- CN202421498693.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-06-27
- Publication Date
- 2025-04-08
- Estimated Expiration
- 2034-06-27
AI Technical Summary
When developing water diversion power stations in the deep covered river section, the existing technology faces the problems of basic treatment, flood discharge and energy removal technology, complex construction, blocking river habitats, reservoir area flooding and engineering investment.
Designing a first hub structure, including excavating a front water inlet pond on the deep covered riverbed, and setting up trapezoidal dark dams on the upstream and downstream sides, combining the upstream anti-shock section and the downstream sea-flow section to simplify basic treatment and flood discharge and energy-elimination building design.
By simplifying basic treatment and flood discharge and energy disposal design, the impact of power station development on the ecological environment and reservoir area flooding is reduced, and the coordination problem between power station development and environmental protection and land protection is solved, and it is technically and economically feasible.
Smart Images
Figure CN222730484U_ABST
Abstract
Description
Technical Field
[0001] The utility model belongs to the technical field of water conservancy and hydropower engineering, and specifically relates to a head hub structure suitable for a water diversion power station in a river section with a deep overburden layer. Background Art
[0002] A diversion power station usually builds a headwater hub upstream of a river section to take in water, and diverts water to the downstream of the river section through a long diversion channel to concentrate the drop between river sections to form a high head for power generation. Its notable feature is that the water backfill height of the headwater hub is usually not large, and it mainly relies on the long diversion channel to concentrate the drop in the river section. In actual design, the headwater hub of a diversion power station will be distributed with soft covering layers of varying thicknesses. Its foundation bearing capacity and anti-scouring ability are low, and its permeability is strong. When building a dam, more measures need to be taken to deal with it. Especially when the covering layer is thick, it faces huge technical challenges in foundation treatment, anti-seepage, flood discharge and energy dissipation. At the same time, there are also problems such as complex construction, blocking the natural habitat of the river, flooding of the reservoir area, and large project investment. Utility Model Content
[0003] The purpose of the utility model is to provide a head hub structure that can meet the water intake needs of the power station, simplify the design of foundation treatment and flood discharge and energy dissipation buildings, and reduce the impact of the power station development on the ecological environment and reservoir flooding when developing a water diversion power station in a river section with a deep overburden layer.
[0004] A head hub structure suitable for a water diversion power station in a river section with a deep overburden layer, characterized in that: it includes a water inlet forebay formed by excavating a riverbed with a deep overburden layer, the minimum working water depth of the water inlet forebay S=cv√b, wherein c is an empirical coefficient, the value range is 0.55~0.73, takes a small value for symmetrical water inflow and a large value for lateral water inflow; v is the water flow velocity of the gate section; d is the height of the gate orifice; the upstream and downstream bottom boundaries of the water inlet forebay are respectively connected to the power station through a water diversion channel, and the upstream and downstream boundaries of the water inlet forebay extend from the water inlet of the water diversion channel to both sides respectively, and the water inlet The boundaries of the left and right banks of the water front pool are set from the bottom of the water front pool to the slopes on both sides. The elevation of the bottom of the water front pool = dead water level - minimum working water depth - water inlet height of the water diversion channel - silt thickness; upstream dam and downstream dam are set on the upstream and downstream sides of the water front pool respectively. The cross-sections of the upstream dam and the downstream dam are trapezoidal. The dam top elevations of the two dams are lower than the natural water level of the river and higher than the natural riverbed line. An upstream anti-scouring section is set on the upstream side of the upstream dam, and a downstream sea floodplain section is set on the downstream side of the downstream dam. Both the upstream anti-scouring section and the downstream sea floodplain section are cross-river and connected with the slopes on both sides.
[0005] Preferably, a concrete anti-seepage plate with structural joints is provided at the bottom of the pool before water inlet, and the spacing between the structural joints is 20m.
[0006] Furthermore, the normal water level of the water inlet front pool is the natural water level corresponding to the multi-year average flow of the river, and the dead water level is the natural water level corresponding to the multi-year average dry season flow.
[0007] Furthermore, the upstream anti-scouring section and the downstream sea floodplain section are composed of wire mesh gabions, reinforced concrete blocks or large-diameter rock masses laid along the natural riverbed.
[0008] Preferably, the upstream and downstream slope ratio of the upstream dark dam to the downstream dark dam is 1:0.5.
[0009] The beneficial effects of the utility model are: by excavating the thick overburden of the riverbed to form a water intake forepool, and building an upstream dark dam and a downstream dark dam on the upstream and downstream sides, the water intake demand of the power station is met, the technical difficulty of the foundation treatment and flood discharge and energy dissipation of the conventional head hub dam construction is reduced, and the coordination problem of power station development and environmental protection and land protection is solved. The head hub solution is technically and economically feasible, and has good applicability when developing water diversion power stations in river sections with thick overburden, and has good application prospects. BRIEF DESCRIPTION OF THE DRAWINGS
[0010] Figure 1 This is a longitudinal section of the head structure of a water diversion power station suitable for river sections with deep overburden.
[0011] Figure 2 This is a cross-sectional view of the head structure of a water diversion power station suitable for river sections with deep overburden.
[0012] Among them, there are water inlet front pool 1, upstream dam 2, downstream dam 3, upstream anti-scouring section 4, downstream seafloor section 5, concrete anti-seepage plate 6, water diversion channel 7, thick covering layer 8, water surface line 9, natural riverbed line 10, and underlying bedrock 11. DETAILED DESCRIPTION
[0013] Embodiment 1: A head hub structure suitable for a water diversion power station in a river section with a thick overburden layer, wherein a water intake forebay 1 is formed by excavating a riverbed with a thick overburden layer 8, an upstream dam 2 and a downstream dam 3 are respectively arranged upstream and downstream of the water intake forebay 1, an upstream anti-collision section 4 is arranged on the upstream side of the upstream dam, and a downstream sea floodplain section 5 is arranged on the downstream side of the downstream dam.
[0014] In this embodiment, the riverbed thick cover layer 8 is about 80m thick, and the water inlet forebay 1 is formed by digging out part of the riverbed thick cover layer 8. The normal water level of the water inlet forebay 1 is the natural water level corresponding to the multi-year average flow of the river channel, which is 1735.82m, and the dead water level is the natural water level corresponding to the multi-year average dry season flow of the river channel, which is 1732.68m. According to the power station design reference flow of 423m 3 / s and the cross-sectional dimensions of the water inlet 7 of the water diversion channel are 10m×10mcm. The Gordon empirical formula (S=cv√b) is used to calculate that the minimum working depth of the water inlet 7 of the water diversion channel is 12.43m, the designed silt thickness at the bottom of the water inlet forebay 1 is 10m, and the bottom elevation of the water inlet forebay 1 = dead water level - minimum working depth - height of the water inlet 7 of the water diversion channel - silt thickness = 1700.25m. The upstream and downstream bottom boundaries of the water inlet forebay are connected to the power station through the water diversion channel 7, and the upstream and downstream boundaries of the water inlet forebay 1 extend 50m to both sides from the water inlet of the water diversion channel 7 to ensure that the stability of the upstream dam 2 and the downstream dam 3 is not affected when taking water, and at the same time, about 500,000m are formed. 3 The reservoir capacity has a certain reaction and adjustment ability to ensure the safe operation of the unit when the upstream water suddenly changes. The left and right bank boundaries of the water inlet pool 1 are excavated from the bottom of the water inlet pool 1 to the slopes on both sides, removing the unstable covering layer and weathered rock mass to form a stable slope.
[0015] The thick covering layer 8 has strong permeability. In order to reduce the leakage of the water inlet pool 1, a 0.8m thick concrete anti-seepage plate 6 is laid at the bottom of the water inlet pool 1, and structural joints of 15m×15m are set in the longitudinal and transverse directions to adapt to the uneven deformation of the thick covering layer 8.
[0016] The cross-section of the upstream dam 2 and the downstream dam 3 is trapezoidal, with reinforced concrete structure and a dam crest width of 5m. The dam crest elevation of the upstream dam 2 is 1735.32m, 0.5m below the normal water level of the forewater pool 1, and the dam crest elevation of the downstream dam 3 is 1732.38m, 0.3m below the dead water level of the forewater pool 1. The dam crest elevation is lower than the water surface line 9 and higher than the natural riverbed line 10. The water flows over the crest without blocking the natural habitat of the river. The water backfill height of the upstream dam 2 and the downstream dam 3 is small to avoid flooding losses in the reservoir area. The upstream and downstream slope ratios of the upstream dam 2 and the downstream dam 3 are 1:0.5.
[0017] The dam foundations of the upstream dam 2 and the downstream dam 3 are not excavated to the underlying bedrock 11, and are located on a thick covering layer 8. The thick covering layer 8 of the dam foundation is compacted to improve its density and bearing capacity. At the same time, a structural joint is provided every 20m along the dam axis of the upstream dam 2 and the downstream dam 3 to adapt to the uneven deformation of the thick covering layer 8. The thick covering layer 8 of the dam foundation is not subjected to basic anti-seepage treatment, and a certain amount of infiltration is allowed, which, combined with the overflow from the dam top, can meet the discharge of the river ecological flow.
[0018] The water backflow height of the upstream hidden dam 2 and the downstream hidden dam 3 is extremely small, and basically no flooding of the reservoir area occurs. When a flood comes, the water flow in the river channel is no different from the natural flood flow state. The construction of the upstream hidden dam 2 and the downstream hidden dam 3 does not increase the erosion of the riverbed due to the concentrated drop, and no special flood discharge and energy dissipation facilities are set up.
[0019] The upstream anti-scouring section 4 and the downstream sea floodplain section 5 are located on the upstream side of the upstream dam 2 and the downstream side of the downstream dam 3, respectively. The lengths of the sections along the river are 50m and 80m respectively, and they are connected to the bank slopes on both sides of the river. The upstream anti-scouring section 4 and the downstream sea floodplain section 5 are paved with blocks with a diameter of more than 1.5m along the natural riverbed to ensure that they have sufficient anti-scouring ability when floods come, ensure the stability of the riverbed, and create local dangerous shoals and waterfalls.
[0020] The utility model relates to a head hub of a water diversion power station suitable for a river section with a deep overburden layer. Compared with the traditional water diversion power station head hub damming and water intake method, it sacrifices about 20m of available water head. Compared with the 300m-level water head utilization reduction ratio of the water diversion power station, it greatly simplifies the design of the head hub foundation treatment and flood discharge and energy dissipation buildings on the deep overburden layer 8, protects the natural habitat of the river, overcomes the contradiction between damming and waterlogging and environmental protection and land protection, and can also create a local dangerous shoal and waterfall landscape.
[0021] In summary, the utility model effectively solves various problems in the prior art and has high industrial utilization value.
Claims
1. A head hub structure suitable for a water diversion power station in a river section with a deep overburden layer, characterized by: It includes the forebay formed by excavating the riverbed with a thick overburden layer. The minimum working water depth of the forebay is calculated as S=cv√d, where c is the empirical coefficient, with a value range of 0.55~0.73, taking a smaller value for symmetrical water inflow and a larger value for lateral water inflow; v is the water flow velocity of the gate section; d is the height of the gate orifice; the upstream and downstream bottom boundaries of the forebay are connected to the power station through the water diversion channel, and the upstream and downstream boundaries of the forebay extend to both sides from the water inlet of the water diversion channel, and the left and right bank boundaries of the forebay are from the water diversion channel. The bottom of the pool is laid out toward the bank slopes on both sides, and the elevation of the pool bottom before water inlet = dead water level - minimum working water depth - height of water inlet of the water diversion channel - thickness of silt; an upstream dam and a downstream dam are respectively set on the upstream and downstream sides of the pool before water inlet. The cross-sections of the upstream dam and the downstream dam are trapezoidal, and the elevations of the dam crests of the two dams are lower than the natural water level of the river channel and higher than the natural riverbed line. An upstream anti-scouring section is set on the upstream side of the upstream dam, and a downstream sea floodplain section is set on the downstream side of the downstream dam. Both the upstream anti-scouring section and the downstream sea floodplain section are cross-river connected to the bank slopes on both sides.
2. The head hub structure of a water diversion power station suitable for a river section with a deep overburden layer as claimed in claim 1, characterized in that A concrete anti-seepage plate with structural joints is arranged at the bottom of the pool before water inlet, and the spacing between the structural joints is 20m.
3. The head hub structure of a water diversion power station suitable for a river section with a deep overburden layer as claimed in claim 1, characterized in that The normal water level of the front inlet pool is the natural water level corresponding to the multi-year average flow of the river, and the dead water level is the natural water level corresponding to the multi-year average dry season flow.
4. The head hub structure of a water diversion power station suitable for a river section with a deep overburden layer as claimed in claim 1, characterized in that The upstream anti-scouring section and the downstream sea flooding section are composed of wire mesh gabions, reinforced concrete blocks or large-diameter rock masses laid along the natural riverbed.
5. The head hub structure of a water diversion power station suitable for a river section with a deep overburden layer as claimed in claim 1, characterized in that The upstream and downstream slope ratios of the upstream and downstream dams are 1:0.5.