Construction method for gate shaft of water conveyance tunnel inlet and outlet of pumped storage power station

Abstract

The present invention discloses a construction method for the gate shaft of the water conveyance tunnel inlet and outlet of a pumped-storage power station, including: Step 1, excavation and support of the access section of the inlet and outlet; Step 2, excavation of the gate shaft and construction of the support structure of the gate shaft. The process of excavating the gate shaft and constructing the support structure of the gate shaft is as follows: Step 201, excavate the top shaft section and construct the support for the top shaft section; Step 201, excavate the top shaft section and construct the support for the top shaft section; Step 203, excavate the bottom interface section and construct the support for the bottom interface section. The present invention can timely close and support the surrounding rock structure around the unexcavated bottom interface section, prevent the surrounding rock structure around the bottom interface section from being damaged, ensure the stability of the surrounding rock support, ensure the excavation and shaping of the bottom interface section, reduce the quality control difficulty of the cable anchor support, and improve the construction efficiency of the support for the middle transition section and the bottom interface section.

Description

Technical Field

[0001] The invention belongs to the technical field of pumped-storage power station construction, and particularly relates to a construction method for a gate shaft at the water inlet / outlet of a water conveyance tunnel of a pumped-storage power station. Background Art

[0002] In the construction of the gate shaft project at the water inlet / outlet of a pumped-storage power station, due to the large number of free surfaces, large surrounding rock deformation, and fast deformation speed at the connection position between the gate shaft and the water conveyance tunnel inlet / outlet, especially for the surrounding rock with broken and fissured strata, the existing anchor mesh support method cannot meet the deformation conditions at the connection position between the gate shaft and the water conveyance tunnel inlet / outlet, and it is easy to have large displacement and deformation unloading, resulting in loose internal rock mass and damage to the rock layer structure, leading to the failure of support. At the same time, it brings obstacles to safe production and the rapid sequence conversion of the working face. Moreover, if multiple pressure-dispersive anchor cables are set on both the wall of the water conveyance tunnel and the wall of the gate shaft, there will be an interference phenomenon between the multiple pressure-dispersive anchor cables set on the wall of the water conveyance tunnel and the multiple pressure-dispersive anchor cables set on the wall of the gate shaft. Therefore, a construction method for a gate shaft at the water inlet / outlet of a water conveyance tunnel of a pumped-storage power station should be provided. Summary of the Invention

[0003] The technical problem to be solved by the present invention is to provide a construction method for a gate shaft at the water inlet / outlet of a water conveyance tunnel of a pumped-storage power station in view of the deficiencies in the above-mentioned prior art. The design is reasonable, which can timely close and support the surrounding rock structure around the unexcavated bottom interface section, prevent the surrounding rock structure around the bottom interface section from being damaged, ensure the stability of the surrounding rock support, ensure the excavation forming of the bottom interface section, reduce the quality control difficulty of the anchor cable support, and improve the construction efficiency of the support in the middle transition section and the bottom interface section.

[0004] To solve the above technical problem, the technical solution adopted by the present invention is: a construction method for a gate shaft at the water inlet / outlet of a water conveyance tunnel of a pumped-storage power station, characterized in that the construction method includes the following steps:

[0005] Step 1: Excavation and support of the connection section at the water inlet / outlet:

[0006] Among them, the support process of the access port connection section is as follows: A plurality of mortar bolts are arranged on the crown arch and side walls of the excavated access port connection section. The mortar bolts have an L-shaped exposed end. Then, a steel mesh is hung on the crown arch and side walls of the excavated access port connection section. A plurality of H-shaped steel belt beams are installed on the crown arch and side walls of the excavated access port connection section. The plurality of H-shaped steel belt beams are arranged at equal intervals along the length direction of the access port connection section. When the H-shaped steel belt beam contacts the L-shaped exposed end of the mortar bolt, the H-shaped steel belt beam is fixedly connected to the L-shaped exposed end. Then, C20 concrete is sprayed to form a C20 concrete support layer;

[0007] Step 2. Excavate the gate shaft and construct the support structure of the gate shaft:

[0008] The gate shaft is divided into a top shaft section, a middle transition section, and a bottom interface section from top to bottom. The bottom interface section communicates with the access port connection section of the water conveyance tunnel. The gate shaft support structure includes a top shaft section support arranged on the shaft wall of the top shaft section, a middle transition section support arranged on the shaft wall of the middle transition section, and a bottom interface section support arranged on the shaft wall of the bottom interface section. The excavation of the gate shaft and the construction process of the gate shaft support structure are as follows:

[0009] Step 201. Excavate the top shaft section and construct the top shaft section support:

[0010] Among them, the construction process of the top shaft section support is as follows: A plurality of mortar bolts are arranged on the shaft wall of the excavated top shaft section. Then, a steel mesh is hung on the shaft wall of the excavated top shaft section. Then, C20 concrete is sprayed to form a C20 concrete support layer;

[0011] Step 202. Excavate the middle transition section and construct the middle transition section support:

[0012] Among them, the construction process of the middle transition section support is as follows: arrange a plurality of mortar bolts on the shaft wall of the excavated middle transition section, hang a steel mesh on the shaft wall of the excavated middle transition section, install an H-shaped steel belt beam on the shaft wall of the excavated middle transition section. The H-shaped steel belt beam is arranged circumferentially along the shaft wall of the middle transition section, and the H-shaped steel belt beam is fixedly connected to the L-shaped exposed end of the mortar bolt. Then, spray C20 concrete to form a C20 concrete support layer. After that, drill a plurality of first inclined tension anchor cable installation holes and a plurality of second inclined tension anchor cable installation holes in the formed C20 concrete support layer. Both the first inclined tension anchor cable installation holes and the second inclined tension anchor cable installation holes penetrate obliquely to the C20 concrete support layer of the water inlet and outlet connection section. Then, insert and anchor the first inclined tension anchor cable in each of the first inclined tension anchor cable installation holes, and insert and anchor the second inclined tension anchor cable in each of the second inclined tension anchor cable installation holes;

[0013] Step 203, excavate the bottom interface section and construct the bottom interface section support:

[0014] Among them, the construction process of the bottom interface section support is as follows: arrange a plurality of mortar bolts on the shaft wall of the excavated bottom interface section, hang a steel mesh on the shaft wall of the excavated bottom interface section, install an H-shaped steel belt beam on the shaft wall of the excavated bottom interface section. The H-shaped steel belt beam is arranged circumferentially along the shaft wall of the bottom interface section, and the H-shaped steel belt beam is fixedly connected to the L-shaped exposed end of the mortar bolt. Then, spray C20 concrete to form a C20 concrete support layer.

[0015] The construction method of the water inlet and outlet gate shaft of the pumped storage power station water conveyance tunnel as described above is characterized in that: the excavation and support of the water inlet and outlet connection section, the excavation and support construction of the top shaft section, and the excavation and bottom interface section support construction of the excavated bottom interface section all need to be carried out in segments alternately.

[0016] The construction method of the water inlet and outlet gate shaft of the pumped storage power station water conveyance tunnel as described above is characterized in that: in step two, the length of the mortar bolt ranges from 6m to 7m, a plurality of the mortar bolts are arranged in a plum blossom shape, the row spacing between adjacent two rows of the mortar bolts is 1.5m, the length of the L-shaped exposed end is 0.5m, the H-shaped steel belt beam is a circular steel belt beam matching the inner wall of the gate shaft, and the spacing between adjacent two H-shaped steel belt beams along the vertical direction of the gate shaft is 1.5m, and the thickness of the C20 concrete support layer ranges from 10cm to 15cm.

[0017] The construction method of the gate shaft at the water inlet and outlet of the water conveyance tunnel of the pumped-storage power station described above is characterized in that: in step one, the H-shaped steel belt beam includes an arc section matching the crown arch of the section connected to the water inlet and outlet and a straight section matching the side wall, and the distance between two adjacent H-shaped steel belt beams is 0.5 m.

[0018] The construction method of the gate shaft at the water inlet and outlet of the water conveyance tunnel of the pumped-storage power station described above is characterized in that: a plurality of first obliquely tensioned anchor cable installation holes and a plurality of second obliquely tensioned anchor cable installation holes are arranged at equal intervals along the circumferential direction of the middle transition section. A plurality of first obliquely tensioned anchor cable installation holes are located above a plurality of second obliquely tensioned anchor cable installation holes. The inclination angle of the first obliquely tensioned anchor cable installation holes ranges from 55° to 60°, and the inclination angle of the second obliquely tensioned anchor cable ranges from 70° to 75°.

[0019] The present invention has the following advantages compared with the prior art:

[0020] 1. When constructing the support for the middle transition section in step 202 of the present invention, by combining the mortar anchor rods, steel mesh sheets, H-shaped steel belt beams, C20 concrete support layers, first obliquely tensioned anchor cables and second obliquely tensioned anchor cables, the surrounding rock structure around the unexcavated bottom interface section can be timely and hermetically supported, so that the surrounding rock structure around the bottom interface section is not damaged, ensuring the stability of the surrounding rock support and ensuring the excavation forming of the bottom interface section.

[0021] 2. In step 202 of the present invention, by arranging a plurality of first obliquely tensioned anchor cables and a plurality of second obliquely tensioned anchor cables, the plurality of first obliquely tensioned anchor cables and the plurality of second obliquely tensioned anchor cables penetrate obliquely through the C20 concrete support layer of the water inlet and outlet connection section, and a circular tensioned anchoring support structure is formed in the surrounding rock structure around the unexcavated bottom interface section. It is not necessary to arrange a plurality of pressure-dispersive anchor cables on both the tunnel wall of the water conveyance tunnel and the shaft wall of the gate shaft, which can avoid the interference between the plurality of pressure-dispersive anchor cables arranged on the tunnel wall of the water conveyance tunnel and the plurality of pressure-dispersive anchor cables arranged on the shaft wall of the gate shaft, reducing the quality control difficulty of the anchor cable support and improving the construction efficiency of the support for the middle transition section and the bottom interface section.

[0022] 3. The construction process of the present invention is reasonably designed, convenient for construction and popularization and application.

[0023] In summary, the present invention is reasonably designed, can timely and hermetically support the surrounding rock structure around the unexcavated bottom interface section, so that the surrounding rock structure around the bottom interface section is not damaged, ensuring the stability of the surrounding rock support, ensuring the excavation forming of the bottom interface section, reducing the quality control difficulty of the anchor cable support, and improving the construction efficiency of the support for the middle transition section and the bottom interface section.

[0024] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Description of the Drawings

[0025] Figure 1 is a flowchart of the present invention.

[0026] Figure 2 is a schematic structural diagram of the present invention.

[0027] Figure 3 is a schematic diagram of the support structure of the water inlet and outlet connection section of the present invention.

[0028] Figure 4 is a schematic diagram of the support structure of the middle transition section of the present invention.

[0029] Description of the Reference Numerals:

[0030] 1 - water conveyance tunnel; 2 - water inlet and outlet connection section; 3 - top shaft section;

[0031] 4 - middle transition section; 5 - bottom interface section; 6 - mortar anchor bolt;

[0032] 6-1 - L-shaped exposed end 7 - H-shaped steel strip beam;

[0033] 8-1 - first diagonal tension anchor cable installation hole; 8-2 - first diagonal tension anchor cable installation hole;

[0034] 9-1 - first diagonal tension anchor cable; 9-2 - second diagonal tension anchor cable;

[0035] 10 - steel mesh; 11 - C20 concrete support layer. Detailed Embodiments

[0036] As Figures 1 to 4 shown, a construction method for the water inlet and outlet gate shaft of the water conveyance tunnel of a pumped-storage power station, the construction method comprising the following steps:

[0037] Step 1, excavation and support of the water inlet and outlet connection section 2:

[0038] Among them, the support process of the access port connection section 2 is as follows: A plurality of mortar bolts 6 are arranged on the crown arch and side walls of the excavated access port connection section 2. The mortar bolt 6 has an L-shaped exposed end 6-1. Then, a steel mesh 10 is hung on the crown arch and side walls of the excavated access port connection section 2. A plurality of H-shaped steel strip beams 7 are installed on the crown arch and side walls of the excavated access port connection section 2. The plurality of H-shaped steel strip beams 7 are arranged at equal intervals along the length direction of the access port connection section 2. When the H-shaped steel strip beam 7 contacts the L-shaped exposed end 6-1 of the mortar bolt 6, the H-shaped steel strip beam 7 is fixedly connected to the L-shaped exposed end 6-1. Then, C20 concrete is sprayed to form a C20 concrete support layer 11;

[0039] Step 2. Excavate the gate shaft and construct the support structure of the gate shaft:

[0040] The gate shaft is successively divided into a top shaft section 3, a middle transition section 4, and a bottom interface section 5 from top to bottom. The bottom interface section 5 communicates with the access port connection section 2 of the water conveyance tunnel 1. The support structure of the gate shaft includes a top shaft section support arranged on the shaft wall of the top shaft section 3, a middle transition section support arranged on the shaft wall of the middle transition section 4, and a bottom interface section support arranged on the shaft wall of the bottom interface section 5. The excavation of the gate shaft and the construction process of the support structure of the gate shaft are as follows:

[0041] Step 201. Excavate the top shaft section 3 and construct the top shaft section support:

[0042] Among them, the construction process of the top shaft section support is as follows: A plurality of mortar bolts 6 are arranged on the shaft wall of the excavated top shaft section 3. Then, a steel mesh 10 is hung on the shaft wall of the excavated top shaft section 3. Then, C20 concrete is sprayed to form a C20 concrete support layer 11;

[0043] Step 202. Excavate the middle transition section 4 and construct the middle transition section support:

[0044] Among them, the construction process of the middle transition section support is as follows: arrange a plurality of mortar bolts 6 on the shaft wall of the excavated middle transition section 4, hang a steel mesh 10 on the shaft wall of the excavated middle transition section 4, install an H-shaped steel belt beam 7 on the shaft wall of the excavated middle transition section 4, the H-shaped steel belt beam 7 is arranged circumferentially along the shaft wall of the middle transition section 4, and fixedly connect the H-shaped steel belt beam 7 with the L-shaped exposed end 6-1 of the mortar bolt 6. Then, spray C20 concrete to form a C20 concrete support layer 11. After that, drill a plurality of first inclined tension anchor cable installation holes 8-1 and a plurality of second inclined tension anchor cable installation holes 8-2 on the formed C20 concrete support layer 11. Both the first inclined tension anchor cable installation holes 8-1 and the second inclined tension anchor cable installation holes 8-2 penetrate obliquely through the C20 concrete support layer 11 of the water inlet and outlet connection section 2. Then, insert and anchor a first inclined tension anchor cable 9-1 into each of the first inclined tension anchor cable installation holes 8-1, and insert and anchor a second inclined tension anchor cable 9-2 into each of the second inclined tension anchor cable installation holes 8-2;

[0045] Step 203: Excavate the bottom interface section 5 and construct the bottom interface section support:

[0046] Among them, the construction process of the bottom interface section support is as follows: arrange a plurality of mortar bolts 6 on the shaft wall of the excavated bottom interface section 5, hang a steel mesh 10 on the shaft wall of the excavated bottom interface section 5, install an H-shaped steel belt beam 7 on the shaft wall of the excavated bottom interface section 5, the H-shaped steel belt beam 7 is arranged circumferentially along the shaft wall of the bottom interface section 5, and fixedly connect the H-shaped steel belt beam 7 with the L-shaped exposed end 6-1 of the mortar bolt 6. Then, spray C20 concrete to form a C20 concrete support layer 11.

[0047] In this embodiment, when constructing the middle transition section support in step 202, by combining the mortar bolt 6, the steel mesh 10, the H-shaped steel belt beam 7, the C20 concrete support layer 11, the first inclined tension anchor cable 9-1 and the second inclined tension anchor cable 9-2, the surrounding rock structure around the unexcavated bottom interface section 5 can be timely and closed for support, so that the surrounding rock structure around the bottom interface section 5 is not damaged, ensuring the stability of the surrounding rock support and ensuring the formation of the excavated bottom interface section 5.

[0048] In this embodiment, in step 202, by arranging a plurality of first obliquely tensioned anchor cables 9-1 and a plurality of second obliquely tensioned anchor cables 9-2, the plurality of first obliquely tensioned anchor cables 9-1 and the plurality of second obliquely tensioned anchor cables 9-2 penetrate obliquely through the C20 concrete support layer 11 of the water inlet and outlet connection section. The plurality of first obliquely tensioned anchor cables 9-1 and the plurality of second obliquely tensioned anchor cables 9-2 form an annular tensioned anchorage support structure within the surrounding rock structure around the bottom interface section 5 that has not been excavated. It is not necessary to arrange a plurality of pressure-dispersed anchor cables on both the inner wall of the water conveyance tunnel 1 and the inner wall of the gate shaft, which can avoid interference between the plurality of pressure-dispersed anchor cables arranged on the inner wall of the water conveyance tunnel 1 and the plurality of pressure-dispersed anchor cables arranged on the inner wall of the gate shaft, reduce the difficulty of quality control of the anchor cable support, and improve the construction efficiency of the support for the middle transition section and the bottom interface section.

[0049] In this embodiment, the excavation and support of the water inlet and outlet connection section 2, the construction of the excavation and support of the top shaft section 3, and the construction of the excavation and support of the bottom interface section 5 all need to be carried out alternately in sections.

[0050] In this embodiment, in step two, the length of the grouted bolt 6 ranges from 6 m to 7 m. The plurality of grouted bolts 6 are arranged in a plum blossom pattern. The row spacing between adjacent rows of the grouted bolts 6 is 1.5 m. The length of the L-shaped exposed end 6-1 is 0.5 m. The H-shaped steel strip beam 7 is a circular steel strip beam that matches the inner wall of the gate shaft. The spacing between adjacent two H-shaped steel strip beams 7 along the vertical direction of the gate shaft is 1.5 m. The thickness of the C20 concrete support layer 11 ranges from 10 cm to 15 cm.

[0051] In this embodiment, the diameter of the grouted bolt 6 ranges from 25 mm to 35 mm.

[0052] In this embodiment, in step one, the H-shaped steel strip beam 7 includes an arc section that matches the top arch of the water inlet and outlet connection section 2 and a straight section that matches the side wall. The spacing between adjacent two H-shaped steel strip beams 7 is 0.5 m.

[0053] In this embodiment, a plurality of first obliquely tensioned anchor cable installation holes 8-1 and a plurality of second obliquely tensioned anchor cable installation holes 8-2 are arranged at equal intervals along the circumferential direction of the middle transition section 4. The plurality of first obliquely tensioned anchor cable installation holes 8-1 are located above the plurality of second obliquely tensioned anchor cable installation holes 8-2. The inclination angle of the first obliquely tensioned anchor cable installation hole 8-1 ranges from 55° to 60°. The inclination angle of the second obliquely tensioned anchor cable 9-2 ranges from 70° to 75°.

[0054] In this embodiment, the number of the first diagonal stay cables 9-1 and the number of the second diagonal stay cables 9-2 are both seven. The seven first diagonal stay cables 9-1 and the seven second diagonal stay cables 9-2 are arranged at equal intervals along the circumferential direction of the middle transition section 4. The tension of the first diagonal stay cable 9-1 and the tension of the second diagonal stay cable 9-2 are both 1000 KN.

[0055] The above is only a preferred embodiment of the present invention, and does not impose any limitations on the present invention. Any simple modifications, changes, and equivalent structural changes made to the above embodiments according to the technical essence of the present invention still fall within the protection scope of the technical solution of the present invention.

Claims

1. A method for constructing a gate shaft for an inlet and outlet of a water diversion tunnel of a pumped storage power station, characterized in that: The construction method comprises the following steps: Step 1: Excavation and support of the inlet and outlet connection section (2): The supporting process of the water inlet and outlet connection section (2) is as follows: a plurality of mortar anchor rods (6) are arranged on the top arch and side wall of the excavated water inlet and outlet connection section (2), wherein the mortar anchor rod (6) has an L-shaped exposed end (6-1); then, a steel mesh sheet (10) is hung on the top arch and side wall of the excavated water inlet and outlet connection section (2); a plurality of H-shaped steel strip beams (7) are installed on the top arch and side wall of the excavated water inlet and outlet connection section (2); the plurality of H-shaped steel strip beams (7) are arranged at equal intervals along the length direction of the water inlet and outlet connection section (2); when the H-shaped steel strip beams (7) are in contact with the L-shaped exposed end (6-1) of the mortar anchor rod (6), the H-shaped steel strip beams (7) are fixedly connected to the L-shaped exposed end (6-1); then, C20 concrete is sprayed to form a C20 concrete supporting layer (11); Step 2: Excavate the gate shaft and construct the gate shaft support structure: The gate shaft is divided into a top shaft section (3), a middle transition section (4) and a bottom interface section (5) from top to bottom, the bottom interface section (5) being connected to the water inlet and outlet connection section (2) of the water conveyance tunnel (1), the gate shaft support structure comprising a top shaft section support arranged on the shaft wall of the top shaft section (3), a middle transition section support arranged on the shaft wall of the middle transition section (4) and a bottom interface section support arranged on the shaft wall of the bottom interface section (5), the excavation process of the gate shaft and the construction process of the gate shaft support structure are as follows: Step 201, excavating the top shaft section (3), and constructing the top shaft section support: The construction process of the top shaft section support is as follows: a plurality of mortar anchor rods (6) are arranged on the shaft wall of the excavated top shaft section (3); a steel mesh sheet (10) is then hung on the shaft wall of the excavated top shaft section (3); and C20 concrete is then sprayed to form a C20 concrete support layer (11); Step 202: excavating the middle transition section (4) and constructing the middle transition section support: The construction process of the middle transition section support is as follows: arranging a plurality of mortar anchor rods (6) on the well wall of the excavated middle transition section (4), hanging a steel mesh sheet (10) on the well wall of the excavated middle transition section (4), installing an H-shaped steel belt beam (7) on the well wall of the excavated middle transition section (4), arranging the H-shaped steel belt beam (7) circumferentially along the well wall of the middle transition section (4), and fixing the H-shaped steel belt beam (7) to the L-shaped exposed end (6-1) of the mortar anchor rod (6), and then spraying C20 concrete to form a C20 concrete support layer (11), and then, on the formed C2 A plurality of first oblique tension anchor cable installation holes (8-1) and a plurality of second oblique tension anchor cable installation holes (8-2) are drilled on the C20 concrete support layer (11), wherein the first oblique tension anchor cable installation holes (8-1) and the second oblique tension anchor cable installation holes (8-2) are both inclined and penetrate the C20 concrete support layer (11) of the water inlet and outlet connection section (2), and then a first oblique tension anchor cable (9-1) is inserted and anchored in each of the first oblique tension anchor cable installation holes (8-1), and a second oblique tension anchor cable (9-2) is inserted and anchored in each of the second oblique tension anchor cable installation holes (8-2); Step 203, excavating the bottom interface section (5), and constructing the bottom interface section support: The construction process of the bottom interface section support is as follows: a plurality of mortar anchor rods (6) are arranged on the well wall of the excavated bottom interface section (5), a steel mesh sheet (10) is hung on the well wall of the excavated bottom interface section (5), an H-shaped steel belt beam (7) is installed on the well wall of the excavated bottom interface section (5), the H-shaped steel belt beam (7) is arranged circumferentially along the well wall of the bottom interface section (5), and the H-shaped steel belt beam (7) is fixedly connected to the L-shaped exposed end (6-1) of the mortar anchor rod (6), and then C20 concrete is sprayed to form a C20 concrete support layer (11).

2. The construction method of the water inlet and outlet gate shaft of the water diversion tunnel of the pumped storage power station according to claim 1 is characterized in that: The excavation and support of the water inlet and outlet connection section (2), the excavation of the top vertical shaft section (3) and the construction of the top vertical shaft section support, and the excavation of the excavated bottom interface section (5) and the construction of the bottom interface section support all need to be carried out alternately in sections.

3. The construction method of the water inlet and outlet gate shaft of the water diversion tunnel of the pumped storage power station according to claim 1, characterized in that: In step 2, the length of the mortar anchor rod (6) ranges from 6m to 7m, the multiple mortar anchor rods (6) are arranged in a plum blossom shape, the row spacing between two adjacent rows of the mortar anchor rods (6) is 1.5m, the length of the L-shaped exposed end (6-1) is 0.5m, the H-shaped steel belt beam (7) is a circular steel belt beam matching the inner wall of the gate shaft, the spacing between two adjacent H-shaped steel belt beams (7) along the vertical direction of the gate shaft is 1.5m, and the thickness of the C20 concrete support layer (11) ranges from 10cm to 15cm.

4. The construction method of the water inlet and outlet gate shaft of the water diversion tunnel of the pumped storage power station according to claim 1, characterized in that: In step 1, the H-shaped steel strip beam (7) includes an arc section matching the top arch of the inlet and outlet connection section (2) and a straight section matching the side wall, and the distance between two adjacent H-shaped steel strip beams (7) is 0.5m.

5. The construction method of the water inlet and outlet gate shaft of the water diversion tunnel of the pumped storage power station according to claim 1, characterized in that: The plurality of first oblique tension anchor cable installation holes (8-1) and the plurality of second oblique tension anchor cable installation holes (8-2) are arranged at equal intervals along the circumferential direction of the middle transition section (4); the plurality of first oblique tension anchor cable installation holes (8-1) are located above the plurality of second oblique tension anchor cable installation holes (8-2); the inclination angle of the first oblique tension anchor cable installation holes (8-1) ranges from 55° to 60°, and the inclination angle of the second oblique tension anchor cable (9-2) ranges from 70° to 75°.

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