Water inlet / outlet building combined structure type for loess stratum

Abstract

The utility model provides a water inlet / outlet building combined structure type for loess strata, namely a water inlet / outlet building arranged in an upper reservoir, and strata at the bottoms of the upper reservoir and the water inlet / outlet building are a rock stratum and a loess layer in sequence from bottom to top. The water inlet / outlet building comprises a side type water inlet / outlet, an emergency gate tower and a water diversion vertical shaft, the side type water inlet / outlet is formed in the downstream side of the upper reservoir, the emergency gate tower is built on the loess layer and communicated with the side type water inlet / outlet, one end of the water diversion vertical shaft is communicated with the emergency gate tower, and the other end of the water diversion vertical shaft is communicated with the emergency gate tower. The other end of the diversion shaft serves as the starting end of the water pipeline; a supporting body is arranged at the bottom of the emergency gate tower, penetrates through the loess layer and is embedded into the rock stratum. The foundation treatment problem of the thicker loess layer is solved, the loess collapsibility is reduced, the bearing capacity of the base is improved, and the foundation settlement is reduced.

Description

Technical Field

[0001] The utility model belongs to the technical field of pumped storage power station engineering, and in particular relates to a combined structural type of water inlet / outlet buildings used in loess strata. Background Art

[0002] The inlet / outlet of a pumped storage power station is an engineering facility built in the upper and lower reservoirs to control water flow. Its function is to reasonably allocate the power generation or pumping water volume of the hydraulic units according to the load requirements of the power system to ensure the safe and economical operation of the power station. Since a pumped storage power station has two operating conditions, pumping (water pump condition) and power generation (turbine condition), the water flow is bidirectional. The inlet and outlet of a pumped storage power station are combined into one. The upper reservoir is the inlet in the power generation condition and the outlet in the pumping condition, and vice versa, so they are collectively referred to as inlets / outlets.

[0003] The inlet / outlet buildings of pumped storage power stations must adapt to the hydraulic conditions of two-way water flow as well as the characteristics of frequent and large fluctuations in water levels. Usually, a combination of vertical inlet / outlet + gate wells is adopted, which has flexible layout and relatively low requirements for terrain and geological conditions. The excavation volume is small, the structure is generally circular in cross-section, the head loss is small, the structure is simple in force, which is conducive to engineering construction and structural safety, and can better solve the problem of inlet / outlet crossing the dam.

[0004] At present, common shaft-type inlet / outlet structures are such as patent announcement number CN103205954A, which discloses a shaft-type inlet / outlet structure for a pumped-storage power station. The flow channel formed between the diverter piers is used for both water inlet and water outlet conditions. Since the diverter piers are fixed, the structure of the flow channel can only be fixed. For water outlet or water inlet, if the flow channel gradually increases along the direction of water flow, the water flow velocity can be effectively alleviated, thereby reducing the mechanical energy lost by internal collision of the water flow and collision between the water flow and the flow channel. However, the fixed flow channel structure is bound to make it impossible for one of the water outlet or water inlet to achieve the gradual increase of the flow channel along the direction of water flow. The head loss of the inlet and outlet of this structure will be relatively large.

[0005] Although there are well-type water inlet and outlet buildings for pumped-storage power stations such as the one disclosed in patent announcement number CN206736873U, which respectively realize the water discharge and water inlet conditions by setting an upper diverter plate and a lower inlet plate, the integral structure of the two plates is large in volume and inconvenient to install. In addition, after the two plates are stacked, the upper and lower flow channels also overlap. Although the electromagnetic valve of the flow channel can be opened and closed to realize the opening and closing of the flow channel, even so, the closed flow channel will also affect the open flow channel, causing the water flow through the open flow channel to be turbulent and swirling, and finally causing unnecessary head loss. In addition, the patent, such as the electromagnetic valve, the upper and lower plate welding form, shows that the scheme is only applicable to small well-type water inlets and outlets, and is not applicable to large well-type water inlets and outlets used in pumped-storage power stations.

[0006] In addition, for the geological conditions of thick loess, if a vertical inlet / outlet + gate well type is adopted, about 3 / 4 of the height of the gate well will be in the loess layer and in the open air, and there will be risks in the completion of the gate well, its own stability and structural safety. Utility Model Content

[0007] In order to avoid the well formation and stability problems of gate wells in thick loess layers and solve the foundation treatment problem of thick loess layers, the utility model provides a combined structural type of inlet / outlet buildings for loess layers, which not only solves the foundation treatment problem of thick loess layers and improves the bearing capacity of the base, but also reduces the loess collapsibility and foundation settlement.

[0008] In order to achieve the above purpose, the utility model adopts the following technical solutions:

[0009] A combined structural type of an inlet / outlet building for loess strata, namely, an inlet / outlet building arranged in an upper reservoir, wherein the strata at the bottom of the upper reservoir and the inlet / outlet building are rock strata and loess strata from bottom to top, the inlet / outlet building comprises a side inlet / outlet, an emergency gate tower and a water diversion shaft, the side inlet / outlet being arranged on the downstream side of the upper reservoir, the emergency gate tower being built on the loess stratum and being connected with the side inlet / outlet, one end of the water diversion shaft being connected with the emergency gate tower, and the other end being used as the starting end of a water delivery pipeline; in addition, a support body is provided at the bottom of the emergency gate tower, and the support body passes through the loess stratum and is embedded in the rock stratum.

[0010] Furthermore, the side inlet / outlet includes an inlet / outlet straight section and an inlet / outlet diffusion section, the inlet / outlet straight section is arranged on the side close to the upper reservoir, the inlet / outlet diffusion section is behind the inlet / outlet straight section, the large diameter end of the inlet / outlet diffusion section is connected to the inlet / outlet straight section, and the small diameter end of the inlet / outlet diffusion section is connected to the emergency gate tower.

[0011] As a further preferred embodiment of the present invention, the support body comprises a plurality of concrete cast-in-place piles arranged side by side and at intervals.

[0012] Furthermore, the concrete cast-in-place piles are arranged at the bottom of the emergency gate tower, with a layout range of 20 to 30 m along the water flow direction and 25 to 29 m perpendicular to the water flow direction.

[0013] Preferably, the pile diameter of the concrete bored pile is ∅90-110 cm, the length of each concrete bored pile is 50-70 m, and the spacing between adjacent concrete bored piles is 2-4 m.

[0014] Furthermore, the loess layer is divided into Q3 Malan loess layer, Q2 Lishi loess layer and Q1 Wucheng loess layer from top to bottom, the thickness of the bottom of the accident gate tower is 35~50m from the Q2 Lishi loess layer, and the concrete bored piles pass through the Q2 Lishi loess layer and Q1 Wucheng loess layer from top to bottom and are embedded in the rock layer.

[0015] Compared with the prior art, the beneficial effects of the utility model are:

[0016] 1. The utility model arranges a gate tower in the reservoir. The gate tower is located at the downstream side of the upper reservoir and close to the water pipeline to avoid the well formation and stability problems of the accident gate well in the thick loess layer.

[0017] 2. The utility model adopts a method of arranging multiple concrete bored piles at the bottom of the accident gate tower, which solves the problem that the loess foundation cannot meet the requirements for the foundation of concrete buildings and reduces foundation settlement. The concrete bored piles successively pass through the Q2 Lishi loess layer and the Q1 Wucheng loess layer and then are embedded in the rock layer, thereby improving the bearing capacity of the base.

[0018] The above description is only an overview of the technical solution of the utility model. In order to more clearly understand the technical means of the utility model and implement it according to the contents of the specification, the following is a detailed description of the preferred embodiments of the utility model in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other design solutions and drawings can be obtained based on these drawings without paying creative work.

[0020] Figure 1 Schematic diagram of the inlet / outlet structure for loess strata.

[0021] Description of reference numerals:

[0022] 1. Upper reservoir;

[0023] 2. Side water inlet / outlet;

[0024] 3. Accident gate tower;

[0025] 4. Dam;

[0026] 5. Concrete cast-in-place piles;

[0027] 6. Q3 Malan loess layer;

[0028] 7. Q2 Lishi loess layer;

[0029] 8. Q1 Wucheng loess layer;

[0030] 9. Rock formation;

[0031] 10. Water diversion shaft.

[0032] In order to make the above-mentioned purposes, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below in conjunction with the accompanying drawings and specific implementation methods. DETAILED DESCRIPTION

[0033] The content of the present invention can be further understood in conjunction with the following detailed description of the preferred implementation method of the present invention and the included embodiments. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as those generally understood by ordinary technicians in the field to which the present invention belongs. If the definition of a specific term disclosed in the prior art is inconsistent with any definition provided in the present invention, the definition of the term provided in the present invention shall prevail.

[0034] In a typical implementation of this application, please refer to Figure 1 , a combined structural type of an inlet / outlet building for a loess stratum, that is, an inlet / outlet building arranged in an upper reservoir 1, wherein the strata at the bottom of the upper reservoir 1 and the inlet / outlet building are, from bottom to top, a rock stratum 9 and a loess stratum, specifically, the inlet / outlet building comprises a side inlet / outlet 2, an emergency gate tower 3 and a water diversion shaft 10, wherein the side inlet / outlet 2 is arranged on the downstream side of the upper reservoir 1, the emergency gate tower 3 is built on the loess stratum and is connected to the side inlet / outlet 2, one end of the water diversion shaft 10 is connected to the emergency gate tower 3, and the other end serves as the starting end of a water delivery pipeline; it is worth mentioning that a support body is provided at the bottom of the emergency gate tower 3, wherein the support body passes through the loess stratum and is embedded in the rock stratum 9.

[0035] In a specific embodiment, the side inlet / outlet includes an inlet / outlet straight section and an inlet / outlet diffusion section, the inlet / outlet straight section is arranged on a side close to the upper reservoir 1, the inlet / outlet diffusion section is behind the outlet straight section, the large diameter end of the inlet / outlet diffusion section is connected to the inlet / outlet straight section, and the small diameter end of the inlet / outlet diffusion section is connected to the accident gate tower 3.

[0036] It should be further explained that the loess layer is divided into Q3 Malan loess layer 6, Q2 Lishi loess layer 7 and Q1 Wucheng loess layer 8 from top to bottom, the bottom of the accident gate tower 3 is 35~50m thick from the Q2 Lishi loess layer 7, and the concrete bored piles 5 pass through the Q2 Lishi loess layer 7 and Q1 Wucheng loess layer 8 from top to bottom and are embedded in the rock layer 9.

[0037] In the utility model, the upper reservoir 1 is limited by special topographic and geological conditions, and the inlet / outlet structure is located on the loess layer. From top to bottom, the loess is divided into Q3 Malan loess layer 6, Q2 Lishi loess layer 7 and Q1 Wucheng loess layer 8, with a total thickness of about 60m. Among them, the Q1 Wucheng loess layer does not have collapsibility, the upper soil layer of the Q2 Lishi loess layer has collapsibility, and the Q3 Malan loess layer has collapsibility. In order to reduce the impact of loess collapsibility, the loess within the scope of the upper reservoir inlet / outlet building is excavated to the area of ​​Q2 Lishi loess layer 7.

[0038] A combination of a side inlet / outlet + gate tower with a simple shape, better flow pattern and less head loss is adopted in the upper reservoir. If the accident gate tower 3 is built directly on loess, the foundation bearing capacity cannot meet the specification requirements, which will affect the safety of the dam 4, and the foundation treatment needs to be carried out at the bottom of the gate tower. In the utility model, the thickness of the Q2 Lishi loess layer 7 at the bottom of the accident gate tower is about 40m, and the thickness of the Q1 Wucheng loess layer 8 at the bottom of the layer is about 15m. Below the loess layer is the Triassic feldspar sandstone and mixed sandstone with unequal thicknesses 9. The bottom of the gate tower is supported by a support body, which includes a plurality of concrete cast-in-place piles 5 arranged side by side and at intervals. In specific implementation, the concrete cast-in-place piles 5 are arranged at the bottom of the accident gate tower 3, and the layout range is 20~30m along the water flow direction (i.e., the upstream and downstream direction) and 20~29m vertical to the water flow direction (i.e., the left and right sides). The pile diameter of the concrete pile 5 is ∅90-110 cm, the length of each concrete pile 5 is 50-70 m, and the distance between adjacent concrete piles 5 is 2-4 m.

[0039] In some specific embodiments, the concrete piles 5 are preferably arranged in a range of 25m in the upstream and downstream directions and 26.9m in the direction perpendicular to the water flow. The concrete piles 5 preferably have a pile diameter of ∅100cm, each concrete pile 5 preferably has a length of 60m, and adjacent concrete piles 5 preferably have a spacing of 3m.

[0040] When in use, the combined structure of the water inlet / outlet building for loess strata provided by the utility model is located in the upper reservoir, and in the pumped storage power station project, it serves as the starting point (turbine working condition) or end point (water pump working condition) of the water transmission and power generation system. The water in the reservoir passes through the straight section and diffusion section of the water inlet / outlet, and then connects to the gate tower, and finally connects to the water transmission pipeline through the water diversion shaft, so that the water in the reservoir circulates through the plant to achieve the purpose of power generation or pumping water.

[0041] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the utility model, rather than to limit it. Although the utility model has been described in detail with reference to the aforementioned embodiments, ordinary technicians in this field should understand that they can still modify the technical solutions recorded in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not make the essence of the corresponding technical solution deviate from the scope of the technical solution of the embodiments of the utility model.

Claims

1. A combined structure of an inlet / outlet building for loess strata, namely, an inlet / outlet building arranged in an upper reservoir (1), wherein the strata at the bottom of the upper reservoir (1) and the inlet / outlet building are, from bottom to top, a rock stratum (9) and a loess stratum, characterized in that: The water inlet / outlet structure comprises a side water inlet / outlet (2), an emergency gate tower (3) and a water diversion shaft (10); the side water inlet / outlet (2) is arranged on the downstream side of the upper reservoir (1); the emergency gate tower (3) is built on the loess layer and is connected to the side water inlet / outlet (2); one end of the water diversion shaft (10) is connected to the emergency gate tower (3), and the other end serves as the starting end of the water delivery pipeline; A support body is provided at the bottom of the emergency gate tower (3), and the support body passes through the loess layer and is embedded in the rock layer (9).

2. The combined structure of water inlet / outlet building for loess strata according to claim 1, characterized in that: The side inlet / outlet (2) comprises an inlet / outlet straight section and an inlet / outlet diffuser section, wherein the inlet / outlet straight section is arranged on a side close to the upper reservoir (1), and the inlet / outlet diffuser section is located behind the inlet / outlet straight section, wherein the large diameter end of the inlet / outlet diffuser section is connected to the inlet / outlet straight section, and the small diameter end of the inlet / outlet diffuser section is connected to the emergency gate tower (3).

3. The combined structure of water inlet / outlet building for loess strata according to claim 1, characterized in that: The support body comprises a plurality of concrete cast-in-place piles (5) arranged side by side and at intervals.

4. The combined structure of water inlet / outlet building for loess strata according to claim 3, characterized in that: The concrete cast-in-place piles (5) are arranged at the bottom of the emergency gate tower (3), with a layout range of 20 to 30 m along the water flow direction and 25 to 29 m perpendicular to the water flow direction.

5. The combined structure of water inlet / outlet building for loess strata according to claim 3 or 4, characterized in that: The pile diameter of the concrete bored pile (5) is ∅90-110 cm, the length of each concrete bored pile (5) is 50-70 m, and the distance between adjacent concrete bored piles (5) is 2-4 m.

6. The combined structure of water inlet / outlet building for loess layer as claimed in claim 3, characterized in that: The loess layers include, from top to bottom, a Q3 Malan loess layer (6), a Q2 Lishi loess layer (7) and a Q1 Wucheng loess layer (8); the bottom of the accident gate tower (3) is located on the Q2 Lishi loess layer (7); and the concrete cast-in-place piles (5) pass through the Q2 Lishi loess layer (7) and the Q1 Wucheng loess layer (8) from top to bottom and are then embedded in the rock layer (9).

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