Underground powerhouse drainage gallery structure constructed through TBM equipment and construction method of underground powerhouse drainage gallery structure

Abstract

The invention relates to an underground powerhouse drainage gallery structure constructed by using TBM equipment and a construction method thereof, the structure comprises an assembly hole which is arranged between a ventilation and safety hole and a main transformer exhaust tunnel of an underground powerhouse and is communicated with the main transformer exhaust tunnel, and an underground powerhouse emergency shelter can be arranged at the later stage of the assembly hole for secondary utilization; the first starting hole is formed in one side of the main transformer exhaust tunnel and communicates with the main transformer exhaust tunnel, and the TBM equipment assembled in the assembling hole enters the first starting hole through the main transformer exhaust tunnel; the annular drainage gallery is annular, is arranged in a horizontal plane in the middle of the upper part of the underground powerhouse, and penetrates through the first originating hole; the spiral descending type drainage gallery is spirally arranged around the underground powerhouse, the upper end of the spiral descending type drainage gallery is connected with the first starting hole, and the lower end is connected with a tail gate hole water-collecting well of the underground powerhouse; the diversion tunnel drainage gallery is arranged around the diversion inclined shaft and located above the diversion lower adit, a circle connected end to end is formed, and the diversion tunnel drainage gallery and the spiral drainage gallery are provided with overlapped sections.

Description

Technical Field

[0001] This invention relates to a drainage gallery structure for underground powerhouses constructed using TBM equipment and its construction method. It is applicable to the field of drainage gallery excavation technology for underground powerhouses in hydropower stations.

[0002] Drainage corridors need to be arranged around the underground powerhouse cavern complex of the hydropower station to intercept and divert seepage water from the surrounding rock, reduce the amount of seepage water entering the underground powerhouse cavern complex, prevent structural damage, and improve the operating environment of the power station.

[0003] Traditional drainage corridors are generally arranged in multiple parallel rings, each independent of the others. They are excavated using the drill-and-blast method, which loosens and damages the surrounding rock mass, detrimental to rock stability. In addition, they have disadvantages such as low mechanization, high labor input, high safety risks, long construction period, and poor working environment, which can cause occupational health damage to on-site construction and management personnel and easily lead to safety accidents. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide an underground plant drainage corridor structure and its construction method using TBM equipment, in view of the above-mentioned problems.

[0005] The technical solution adopted in this invention is: an underground powerhouse drainage corridor structure constructed using TBM equipment, comprising: The assembly tunnel is located between the ventilation and safety tunnel and the main transformer exhaust tunnel in the underground plant, and is connected to the main transformer exhaust tunnel. It is used for the assembly of TBM equipment and the installation of power supply lines and slag removal systems. The assembly tunnel can be used as an emergency refuge area in the underground plant for secondary use in the future. The first starting tunnel is located on one side of the main transformer exhaust tunnel and is connected to the main transformer exhaust tunnel. The TBM equipment assembled in the assembly tunnel enters the first starting tunnel through the main transformer exhaust tunnel. The annular drainage corridor, in the shape of a ring, is located in the horizontal plane above the middle of the underground plant and runs through the first starting hole; A spiral-shaped drainage corridor is arranged around the underground plant in a spiral shape, with the upper end of the spiral drainage corridor connected to the first starting hole and the lower end of the spiral drainage corridor connected to the tail gate water collection well of the underground plant. The water diversion tunnel drainage gallery is located around the water diversion inclined shaft and above the water diversion lower horizontal tunnel. The water diversion tunnel drainage gallery forms a loop that is connected end to end and has an overlapping section with the spiral drainage gallery. The annular drainage gallery, spiral drainage gallery, and water diversion tunnel drainage gallery were all excavated by TBM equipment.

[0006] The spiral drainage corridor passes through the tail gate ventilation tunnel, access tunnel, and construction branch tunnel of the underground plant, serving as a channel for slag removal, ventilation, and drainage during the TBM equipment excavation process.

[0007] The tailgate ventilation tunnel, the access tunnel, and the plant construction branch tunnel are respectively provided with a second starting tunnel, a third starting tunnel, and a fourth starting tunnel on one side; the spiral descending drainage gallery runs through the second starting tunnel, the third starting tunnel, and the fourth starting tunnel.

[0008] A maintenance tunnel is constructed between the access tunnel and the main transformer air intake tunnel of the underground powerhouse. The maintenance tunnel connects the access tunnel and the main transformer air intake tunnel, and the spiral descending drainage corridor runs through the maintenance tunnel. The maintenance tunnel can be reused as a traffic loop passage for the underground powerhouse in the future.

[0009] The drainage corridor of the water diversion tunnel is formed by connecting multiple straight sections and multiple connecting sections end to end. The straight sections are located on both sides of the water diversion inclined shaft, and the two ends of the connecting sections connect the first end of one straight section and the second end of another straight section. The connecting section includes an arc connecting section, and the arc connecting section on the water diversion tunnel drainage gallery is tangent to the spiral descending drainage gallery.

[0010] The spiral descending drainage corridor is provided with overflow drainage sections at certain intervals. The bottom plate of the overflow drainage section includes an overflow drainage trough in the middle and drainage ditches on both sides. The overflow drainage trough is covered with a cover plate. The drainage ditches are connected to the overflow drainage trough through several overflow holes. The overflow drainage trough is connected to the spiral descending drainage corridor section below it through several overflow drainage holes.

[0011] A construction method for the underground powerhouse drainage gallery structure includes: Based on the ventilation and safety tunnel and the main transformer exhaust tunnel of the underground powerhouse, the construction assembly tunnel is used; based on the main transformer exhaust tunnel of the underground powerhouse, the first construction starting tunnel is used. The TBM equipment is transported to the assembly tunnel through a ventilation and safety tunnel and a main transformer exhaust tunnel, and the TBM equipment is assembled inside the assembly tunnel. The assembled TBM equipment inside the tunnel is pushed to the first starting tunnel through the main transformer ventilation tunnel. The TBM equipment starts from the first starting tunnel, excavates a circle along the preset circular path and returns to the first starting tunnel to complete the circular drainage corridor. The TBM equipment started again from the first starting tunnel and excavated along the preset spiral path; When the TBM equipment excavates along the preset spiral path to the overlapping section of the spiral descending drainage gallery and the water diversion tunnel drainage gallery, the TBM equipment enters the preset water diversion tunnel drainage path. After the TBM equipment excavates a circle along the preset water diversion tunnel drainage path and returns to the overlapping section, it continues to excavate along the preset spiral path until it reaches the tail gate water collection well of the underground powerhouse. The TBM equipment is received and dismantled in the sump well of the tail gate, and then exits through the tail gate transport tunnel and the access tunnel of the underground plant.

[0012] The beneficial effects of this invention are: This invention uses a spiral descending drainage gallery as the drainage gallery around the underground plant, and connects the annular drainage gallery and the spiral descending drainage gallery through the spiral descending drainage gallery, so as to facilitate the excavation of each gallery by TBM equipment.

[0013] This invention, by employing TBM (Tunnel Boring Machine) excavation, can significantly reduce the loosening and damage to the surrounding rock mass caused by the excavation of underground powerhouse drainage channels, thus promoting rock mass stability. It also boasts advantages such as a high degree of mechanization and automation, significantly reducing labor input, drastically shortening the construction period, and significantly improving the working environment. Furthermore, it reduces safety risks in underground engineering construction and enhances project quality and inherent safety.

[0014] In this invention, the spiral drainage corridor passes through the tail gate ventilation tunnel, the access tunnel, and the construction adit of the underground plant. Thus, the tail gate ventilation tunnel, the access tunnel, and the construction adit can be used as channels for slag removal, ventilation, and drainage during the excavation of the TBM equipment, thereby reducing the difficulty of slag removal, ventilation, and drainage. Attached Figure Description

[0015] Figure 1 This is a three-dimensional diagram of the overall layout of an embodiment of this application.

[0016] Figure 2 This is a cross-sectional view of the overall layout of an embodiment of this application.

[0017] Figure 3 This is a detailed cross-sectional view of a typical TBM tunnel section according to an embodiment of this application.

[0018] Figure 4 This is a detailed cross-sectional view of a typical assembly tunnel section and a maintenance tunnel section according to an embodiment of this application.

[0019] Figure 5 This is a detailed cross-sectional view of a typical tunnel section in an embodiment of this application.

[0020] Figure 6 , Figure 7 This is a schematic diagram of the overflow drainage section in an embodiment of this application.

[0021] The diagram is labeled as follows: 11. Spiral descending drainage gallery; 12. Circular drainage gallery; 13. Water diversion tunnel drainage gallery; 14. Overflow drainage channel; 15. Cover plate; 16. Overflow hole; 21. Assembly hole; 22. Inspection hole; 23. First launching hole; 24. Second launching hole; 25. Third launching hole; 26. Fourth launching hole; 3. Overflow drainage hole. Detailed Implementation

[0022] Example 1: Figure 1 , Figure 2 As shown, this embodiment is an underground plant drainage gallery structure constructed using TBM equipment, including: a spiral descending drainage gallery, a ring drainage gallery, a water diversion tunnel drainage gallery, an assembly tunnel, a maintenance tunnel, a first starting tunnel, a second starting tunnel, a third starting tunnel, and a fourth starting tunnel, etc.

[0023] In this embodiment, the assembly tunnel is located between the ventilation and safety tunnel and the main transformer exhaust tunnel in the underground plant, and is connected to both the ventilation and safety tunnel and the main transformer exhaust tunnel, for assembling TBM equipment; the first starting tunnel is located on the side of the main transformer exhaust tunnel away from the assembly tunnel, is connected to the main transformer exhaust tunnel, and corresponds to the position of the assembly tunnel, and the TBM equipment assembled in the assembly tunnel can enter the first starting tunnel through the main transformer exhaust tunnel.

[0024] In this example, the annular drainage corridor is a ring-shaped structure located in the horizontal plane above the underground powerhouse and passes through the first launching tunnel; the spiral descending drainage corridor is spiral-shaped and surrounds the underground powerhouse, with the upper end of the spiral drainage corridor connected to the first launching tunnel and the lower end of the spiral drainage corridor connected to the tailgate tunnel sump of the underground powerhouse.

[0025] In this embodiment, the spiral drainage corridor passes through the tail gate ventilation tunnel, the access tunnel, and the construction adit of the underground powerhouse, thereby enabling the tail gate ventilation tunnel, the access tunnel, and the construction adit to be used as slag removal, ventilation, and drainage channels during the TBM equipment excavation process.

[0026] In this embodiment, a second starting tunnel, a third starting tunnel, and a fourth starting tunnel are respectively provided on one side of the tail gate ventilation tunnel, the access tunnel, and the plant construction adit. During the excavation process along the spiral drainage corridor, the TBM equipment enters the corresponding chamber from one side of the tail gate ventilation tunnel, the access tunnel, and the plant construction adit, and starts again from the starting tunnel on the other side to carry out subsequent excavation construction.

[0027] In this example, a maintenance tunnel is set up between the access tunnel to the underground plant and the main transformer air intake tunnel. The maintenance tunnel connects the access tunnel to the main transformer air intake tunnel, and the spiral descending drainage corridor runs through the maintenance tunnel.

[0028] In this embodiment, a water diversion tunnel drainage corridor is provided around the water diversion inclined shaft and above the water diversion lower horizontal tunnel. The water diversion tunnel drainage corridor forms a loop that is connected end to end and has an overlapping section with the spiral drainage corridor.

[0029] In this example, the drainage gallery of the water diversion tunnel is formed by connecting four straight segments (straight segments I, II, III, and IV in sequence) and four connecting segments end to end. The four connecting segments include three arc connecting segments and one straight connecting segment. The four straight segments are arranged on both sides of the three water diversion inclined shafts, and the axis of the straight segments is parallel to the axis of the lower water diversion tunnel. The first end of straight segment I is connected to the second end of straight segment II via an arc connecting segment (near the spiral drainage gallery). The first end of straight segment II is connected to the second end of straight segment III via an arc connecting segment (near the water diversion inclined shaft). The first end of straight segment III is connected to the second end of straight segment IV via an arc connecting segment (near the spiral drainage gallery). The first end of straight segment IV is connected to the second end of straight segment I via a straight connecting segment. The straight connecting segments are connected by arc transitions.

[0030] In this embodiment, the arc connecting section between straight segments I and II is tangent to and overlaps with the spiral descending drainage corridor, forming an overlapping section.

[0031] In this embodiment, the annular drainage gallery, spiral drainage gallery, and water diversion tunnel drainage gallery are all formed by excavation using TBM equipment. For example... Figure 3 As shown, the tunnel section excavated by the TBM equipment has a circular cross-section with a diameter of 3.53m and a turning radius of not less than 30m. Figure 4 As shown, in this example, the assembly tunnel and maintenance tunnel have a gate-shaped cross-section, measuring 8.7m × 9.7m, with a length of not less than 42.5m. Figure 5 As shown, in this embodiment, the cross-sections of the first, second, third, and fourth starting holes are circular, with a diameter of 3.9m and a length of not less than 7m.

[0032] The construction method of the underground powerhouse drainage corridor structure in this embodiment specifically includes the following steps: S100. Using the ventilation and safety tunnel and the main transformer exhaust tunnel of the underground powerhouse as construction access, construct the assembly tunnel between the ventilation and safety tunnel and the main transformer exhaust tunnel; using the main transformer exhaust tunnel of the underground powerhouse as construction access, construct the first starting tunnel on one side of the main transformer exhaust tunnel.

[0033] S200: The TBM equipment is transported to the assembly tunnel through the ventilation and safety tunnel and the main transformer exhaust tunnel, and the assembly of the TBM equipment and the installation of the power supply line and slag removal system are completed in the assembly tunnel.

[0034] S300. The assembled TBM equipment inside the tunnel is pushed to the first starting tunnel through the main transformer exhaust tunnel. The TBM equipment starts from the first starting tunnel, excavates a circle along the preset circular path and returns to the first starting tunnel, completing the excavation and construction of the circular drainage corridor.

[0035] The S400 and TBM equipment started again from the first starting tunnel and excavated along the preset spiral path until they reached the tail gate sump of the underground powerhouse, completing the excavation and construction of the spiral descending drainage corridor.

[0036] When the TBM equipment excavates along the preset spiral path to the overlapping section of the spiral descending drainage gallery and the water diversion tunnel drainage gallery, the TBM equipment enters the preset water diversion tunnel drainage path, excavates one circle along the preset water diversion tunnel drainage path and returns to the overlapping section, and then continues to excavate along the preset spiral path.

[0037] When the TBM equipment excavates along the preset spiral path to the tail gate ventilation tunnel, the TBM equipment enters the second starting tunnel located on the other side of the tail gate ventilation tunnel. The TBM equipment starts again from the second starting tunnel and continues to excavate along the preset spiral path. During the continued excavation process, the tail gate ventilation tunnel is used as a channel for slag removal, ventilation and drainage.

[0038] When the TBM equipment excavates along the preset spiral path to the main transformer intake tunnel, it enters the maintenance tunnel between the main transformer intake tunnel and the access tunnel (using the access tunnel and the main transformer intake tunnel as construction channels, the maintenance tunnel construction is completed in advance). In the maintenance tunnel, the TBM equipment is inspected, supplied with power, and slag is removed. Then, the TBM equipment is sent to the third starting tunnel through the access tunnel. The TBM equipment starts again from the third starting tunnel and continues to excavate along the preset spiral path. During the continued excavation, the access tunnel is used as a slag removal, ventilation and drainage channel.

[0039] When the TBM equipment excavates along the preset spiral path to the plant construction adit, the TBM equipment enters the fourth starting hole located on the other side of the plant construction adit through the plant construction adit. The TBM equipment starts again from the fourth starting hole and continues to excavate along the preset spiral path. During the continued excavation process, the plant construction adit is used as a channel for slag removal, ventilation and drainage.

[0040] The drainage corridor descends in a spiral pattern, with the slope of straight sections controlled within 5% and the slope of turning sections controlled within 3%.

[0041] S500: The TBM equipment is received and dismantled in the sump well of the tail gate tunnel, and then exits through the tail gate transport tunnel and the access tunnel of the underground plant.

[0042] S600, pour concrete for the bottom slab of the annular drainage gallery, spiral drainage gallery and water diversion tunnel drainage gallery, and form drainage ditches on the bottom slab; use the annular drainage gallery, spiral drainage gallery and water diversion tunnel drainage gallery to set up drainage curtains for seepage prevention of underground powerhouse.

[0043] Example 2: In Example 1, the annular drainage corridor and the water diversion tunnel drainage corridor discharge water to the collection well through a spiral descending drainage corridor. Since the spiral descending drainage corridor in Example 1 is set up in a spiral shape around the underground plant, its length is relatively long. The flow of the spiral descending drainage corridor will gradually increase like the confluence of rivers, which may exceed the carrying capacity of the drainage ditch in some cases.

[0044] To solve the above problems, such as Figure 6 , 7 As shown, in this embodiment, overflow drainage sections are provided at regular intervals on the spiral descending drainage gallery. The bottom plate of each overflow drainage section includes an overflow drainage trough in the middle and drainage ditches on both sides, which connect with the drainage ditches in the rest of the gallery. The overflow drainage trough and the drainage ditches are separated by a partition wall, and the overflow drainage trough is covered with a cover plate supported by the partition wall. The partition wall has several overflow holes, which connect the drainage ditches and the overflow drainage trough. When the water level in the drainage ditches exceeds a certain level, some water can overflow into the overflow drainage trough through the overflow holes. In this embodiment, the overflow drainage trough is connected to the overflow drainage section of the spiral descending drainage gallery directly below it through several overflow drainage holes.

[0045] In this example, the overflow drainage sections are all located near the collection well, and the vertical positions of each overflow drainage section are basically corresponding. The overflow drainage section at the bottom extends directly to the collection well.

Claims

1. A drainage gallery structure for an underground powerhouse constructed using TBM equipment, characterized in that... ,include: An assembly tunnel is located between the ventilation and safety tunnel and the main transformer exhaust tunnel in the underground plant, and is connected to the main transformer exhaust tunnel. It is used for the assembly of TBM equipment and the installation of power supply lines and slag removal systems. The first starting tunnel is located on one side of the main transformer exhaust tunnel and is connected to the main transformer exhaust tunnel. The TBM equipment assembled in the assembly tunnel enters the first starting tunnel through the main transformer exhaust tunnel. The annular drainage corridor, in the shape of a ring, is located in the horizontal plane above the middle of the underground plant and runs through the first starting hole; A spiral-shaped drainage corridor is arranged around the underground plant in a spiral shape, with the upper end of the spiral drainage corridor connected to the first starting hole and the lower end of the spiral drainage corridor connected to the tail gate water collection well of the underground plant. The water diversion tunnel drainage gallery is located around the water diversion inclined shaft and above the water diversion lower horizontal tunnel. The water diversion tunnel drainage gallery forms a loop that is connected end to end and has an overlapping section with the spiral drainage gallery. The annular drainage gallery, spiral drainage gallery, and water diversion tunnel drainage gallery were all excavated by TBM equipment.

2. The underground powerhouse drainage corridor structure constructed using TBM equipment according to claim 1, characterized in that: The spiral drainage corridor passes through the tail gate ventilation tunnel, access tunnel, and construction branch tunnel of the underground plant, serving as a channel for slag removal, ventilation, and drainage during the TBM equipment excavation process.

3. The underground powerhouse drainage corridor structure constructed using TBM equipment according to claim 1, characterized in that: The tailgate ventilation tunnel, the access tunnel, and the plant construction branch tunnel are respectively provided with a second starting tunnel, a third starting tunnel, and a fourth starting tunnel on one side; the spiral descending drainage gallery runs through the second starting tunnel, the third starting tunnel, and the fourth starting tunnel.

4. The underground powerhouse drainage corridor structure constructed using TBM equipment according to claim 1, characterized in that: A maintenance tunnel is provided between the access tunnel and the main transformer air intake tunnel of the underground plant. The maintenance tunnel connects the access tunnel and the main transformer air intake tunnel and is used for TBM equipment maintenance, subsequent power supply and slag removal. The spiral descending drainage corridor runs through the maintenance tunnel.

5. The underground powerhouse drainage corridor structure constructed using TBM equipment according to claim 1, characterized in that: The drainage corridor of the water diversion tunnel is formed by connecting multiple straight sections and multiple connecting sections end to end. The straight sections are located on both sides of the water diversion inclined shaft, and the two ends of the connecting sections connect the first end of one straight section and the second end of another straight section. The connecting section includes an arc connecting section, and the arc connecting section on the water diversion tunnel drainage gallery is tangent to the spiral descending drainage gallery.

6. The underground powerhouse drainage corridor structure constructed using TBM equipment according to claim 1, characterized in that: The spiral descending drainage corridor is provided with overflow drainage sections at certain intervals. The bottom plate of the overflow drainage section includes an overflow drainage trough in the middle and drainage ditches on both sides. The overflow drainage trough is covered with a cover plate. The drainage ditches are connected to the overflow drainage trough through several overflow holes. The overflow drainage trough is connected to the spiral descending drainage corridor section below it through several overflow drainage holes.

7. A construction method for an underground powerhouse drainage gallery structure as described in any one of claims 1 to 6, characterized in that, include: Based on the ventilation and safety tunnel and the main transformer exhaust tunnel of the underground powerhouse, the construction assembly tunnel is used; based on the main transformer exhaust tunnel of the underground powerhouse, the first construction starting tunnel is used. The TBM equipment is transported to the assembly tunnel through a ventilation and safety tunnel and a main transformer exhaust tunnel, and the TBM equipment is assembled inside the assembly tunnel. The assembled TBM equipment inside the tunnel is pushed to the first starting tunnel through the main transformer ventilation tunnel. The TBM equipment starts from the first starting tunnel, excavates a circle along the preset circular path and returns to the first starting tunnel to complete the circular drainage corridor. The TBM equipment started again from the first starting tunnel and excavated along the preset spiral path; When the TBM equipment excavates along the preset spiral path to the overlapping section of the spiral descending drainage gallery and the water diversion tunnel drainage gallery, the TBM equipment enters the preset water diversion tunnel drainage path. After the TBM equipment excavates a circle along the preset water diversion tunnel drainage path and returns to the overlapping section, it continues to excavate along the preset spiral path until it reaches the tail gate water collection well of the underground powerhouse. The TBM equipment is received and dismantled in the sump well of the tail gate, and then exits through the tail gate transport tunnel and the access tunnel of the underground plant.

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