A silt-proof and anti-scour water-dividing structure for the intersection of a karst tunnel and an underground river

Abstract

The present invention discloses an anti-siltation and anti-impact water-dividing structure for the intersection of a karst tunnel and an underground river. The structure utilizes an upstream water-dividing weir, a downstream force-dissipating weir, a porous box culvert-type V-shaped inverted siphon water pipe and an open overflow channel, so that the karst tunnel structure divides the underground river intersecting therewith into upper and lower water-passing sections; the lower water-passing section is a porous box culvert-type V-shaped inverted siphon water pipe, and the upper water-passing section is an open overflow channel. The water-dividing structure of the present invention diverts the underground river through the karst tunnel according to the dry season and the flood season. The buried depth of the V-shaped inverted siphon hole water pipe is shallow, and there is no need to adjust the water flow gradient of the underground river. In addition, the V-shaped inverted siphon hole water pipe solves the problem of siltation on the upstream side of the lining structure of the upstream karst tunnel. At the same time, the water-dividing weir reduces the impact load of the water flow on the lining structure during the flood season, so that the upper and lower diverted water loads achieve a certain degree of balance.

Description

Technical Field

[0001] The present invention relates to a silt-proof and anti-scour water diversion structure for the intersection of a karst tunnel and an underground river. This structure belongs to the field of tunnel design and construction in karst areas. It is particularly suitable for use in karst tunnel lining structures where the karst tunnel and underground river intersect, the gradient of the underground river is difficult to adjust to avoid the karst tunnel's alignment, and the karst tunnel and underground river share the same elevation. Background Art

[0002] The design and construction of highway and railway tunnels in karst areas often encounter karst underground river systems. These systems are typically composed of various karst cavities, such as karst caves. Their flow is not only recharged by their own groundwater systems but also closely correlated with surface runoff. During periods of heavy rain, their flow and velocity increase rapidly, resulting in flood peaks within a short period of time. Consequently, underground rivers in karst areas experience significant differences in water level, flow and velocity, and sediment load between dry and flood seasons.

[0003] When an underground river intersects a tunnel, conventional structural arrangements require the river to either pass beneath the karst tunnel floor or above the tunnel roof. When the river passes beneath the tunnel floor, even if the river cross-section differs significantly between dry and flood seasons, the depth of the water-passing section below the tunnel floor must be increased to meet flood flow requirements. This necessitates a significant adjustment of the river's channel gradient, a significant challenge for underground rivers. Otherwise, significant sediment will accumulate in the tunnel's water passageway, reducing the water-passing section and causing the river's buoyancy to support and scour the tunnel lining. When the river passes above the tunnel roof, the tunnel lining's water-blocking properties are significant, leading to significant sedimentation upstream of the lining, reducing the water-passing section and making it prone to flow blockages and lateral thrust and impact on the lining during flood seasons.

[0004] Patent CN101864960B discloses a method for constructing a double-arch highway tunnel in a karst area, which includes five steps: 1. Construction preparation; 2. Tunnel portal construction; 3. Construction of the tunnel entrance section using the three-pilot tunnel method and the application of the step excavation method; 4. Construction of the middle connecting section of the tunnel using the middle pilot tunnel method, and the middle pilot tunnel method uses the full-section excavation method; 5. Construction of the tunnel portal section using the three-pilot tunnel method or the middle pilot tunnel method.

[0005] Patent CN101922303B discloses a method for dealing with a karst hall under a dark river in a tunnel, the steps of which include: 1. Finding the location of the dark river karst hall and conducting a geological feature analysis; 2. Excavating auxiliary tunnels to reveal the dark river karst hall; 3. Mechanically cleaning the rock mass with safety hazards, cleaning the accumulation in the dark river hall to an appropriate position above the top of the tunnel, and constructing a diversion channel. At the same time, setting up a water dam at an appropriate position upstream of the dark river to divert the surface water flow of the dark river to the diversion channel for drainage; 4. Constructing a reinforced concrete bottom plate in the dark river hall, and performing downward drilling and grouting on the bottom plate to reinforce the karst accumulation body; 5. Excavating the tunnel.

[0006] Patent CN107268647B discloses a method for constructing an anti-seepage wall at an underground river under conditions of large flow and high velocity water movement. Anti-seepage walls are used to seal large caves or underground rivers in karst areas with large flow and high velocity water movement. The shape and span of the large cave or underground river are determined according to the leakage situation of the anti-seepage wall construction. According to the underground river with the determined shape and span, water-blocking walls with shapes and spans matching the underground river are respectively set on both sides of the axis of the anti-seepage wall at the underground river. The dynamic water on both sides of the axis of the anti-seepage wall at the underground river is blocked by two water-blocking walls, so as to form a cavity in a relatively static water state between the two water-blocking walls. Holes are made in the anti-seepage wall in the cavity to form the anti-seepage wall.

[0007] Patent CN109826081A, a large-scale karst cave, underground river arch span structure and construction in a tunnel, including complete bedrock, arch seats, main arch rings, backfill layer, cave wall protection and steel temporary support. The arch seats are located above the complete bedrock on both sides of the karst cave and underground river. The cave walls are well protected around the karst cave and underground river. The main arch rings are supported on the arch seats on both sides. The backfill layer is between the arch span structure and the upper tunnel structure. The tunnel construction steel temporary support is divided into vertical steel temporary support and longitudinal steel temporary support. The longitudinal steel temporary support is located below the tunnel structure. The tunnel primary support frame falls on the longitudinal steel temporary support. The longitudinal steel temporary support is supported to the bottom of the karst cave using vertical steel temporary support.

[0008] Patent CN110004990A, a method and device for pressure relief construction in basements in water-rich underground river areas. The device includes a water filter pipe installed in a drainage hole and a concealed-stem elastic-seat gate valve and a pressure reducing valve fixed to the outer end of the water filter pipe in sequence. A pressure gauge is installed on the water filter pipe between the concealed-stem elastic-seat gate valve and the pressure reducing valve. Water filter holes are evenly distributed on the lower pipe wall of the water filter pipe, and the water outlet end of the pressure reducing valve is connected to the drainage hose. Summary of the Invention

[0009] Technical problem: The purpose of the present invention is to provide a silt-proof and anti-impact water-dividing structure for the intersection of a karst tunnel and an underground river, so as to solve a series of problems such as poor water flow, siltation, anti-floating of the lining structure and flood impact that may occur when the underground river and the tunnel intersect, and the traditional structural arrangement method either passes through the lower part or the upper part of the karst tunnel.

[0010] Technical solution: The anti-siltation and anti-scour water diversion structure of the present invention at the intersection of a karst tunnel and an underground river includes a sand settling tank, a trash rack, a water diversion weir, an eight-shaped embedded ground anchor plate foundation, an open overflow channel, a wear-resistant rubber belt, two waterproof doors, a porous box culvert type V-shaped inverted siphon water pipe, a force dissipation weir, and a force dissipation pier; the structure is supported by an eight-shaped embedded ground anchor plate foundation, a porous box culvert type V-shaped inverted siphon water pipe is arranged on the eight-shaped embedded ground anchor plate foundation, and a porous box culvert type V-shaped inverted siphon water pipe is arranged on the porous box culvert type V-shaped inverted siphon water pipe. There are two waterproof doors on the siphon water supply pipeline, and open overflow channels are provided on both sides of the two waterproof doors; the upstream of the open overflow channel is the upper water flow section, and a grit chamber is provided upstream of the open overflow channel, a trash rack is provided in the grit chamber, a diversion weir is provided on the right side of the trash rack, and a wear-resistant rubber belt is provided at the connection between the diversion weir and the water inlet of the porous box culvert type V-shaped inverted siphon water supply pipeline; the downstream of the open overflow channel is the lower water flow section, and a stilling weir is provided downstream of the open overflow channel.

[0011] In the water diversion structure, the upstream water diversion weir, the downstream stilling weir, the porous box culvert type V-shaped inverted siphon water supply pipeline and the open overflow channel enable the karst tunnel structure to divide the underground river intersecting with it into upper and lower water-passing sections; the lower water-passing section is a porous box culvert type V-shaped inverted siphon water supply pipeline, which mainly serves as a water-passing channel in the dry season and prevents siltation and sand flushing in the upstream section of the karst tunnel; the upper water-passing section is an open overflow channel, which mainly serves as a water-passing channel in the flood season and prevents siltation and sand flushing in the downstream section of the karst tunnel.

[0012] In the water diversion structure, the sedimentation tank is located at the front end of the upstream side of the water diversion structure; the stilling weir is located at the rear end of the downstream side of the water diversion structure; the trash rack is located in front of the water inlet of the porous box culvert type V-shaped inverted siphon water supply pipeline in the sedimentation tank; the water diversion weir is located on the upstream side close to the outside of the water diversion structure and connected to the edge of the sedimentation tank; the stilling weir is located on the downstream side close to the outside of the water diversion structure; the porous box culvert type V-shaped inverted siphon water supply pipeline passes through the bottom of the karst tunnel structure, connecting the upstream sedimentation tank and the downstream stilling weir; two waterproof doors constitute an inspection door channel, which is placed above the V-shaped inverted siphon water supply pipeline.

[0013] In the water diversion structure, an eight-shaped embedded ground anchor plate foundation is adopted, and a segmented annular reinforced grid frame structure on the outer side of the structure along the longitudinal direction of the tunnel serves as the water diversion structure load-bearing reinforcement component, which is separated from the porous box culvert type V-shaped inverted siphon water supply pipeline and serves as a vertical force transmission component for the water diversion weir and the stilling weir.

[0014] In the water diversion structure, a wear-resistant rubber belt containing vibration-damping beads is arranged on the water-facing surface of the water channel; a wear-resistant rubber belt containing vibration-damping beads is arranged at the connection between the water diversion weir and the water inlet of the porous box culvert type V-shaped inverted siphon water supply pipeline, forming an anti-impact and anti-seepage structure.

[0015] In the water-dividing structure, during the dry season, the underground river water only flows from the porous box culvert type V-shaped inverted siphon water pipe to cross the karst tunnel, and the water-binding effect of the porous box culvert type V-shaped inverted siphon water pipe scours away the sediment deposited in the sedimentation tank during the flood season; during the flood season, the underground river water flows through the two water passages of the porous box culvert type V-shaped inverted siphon water pipe and the open overflow channel to cross the karst tunnel, carrying away the sediment deposited in the porous box culvert type V-shaped inverted siphon water pipe and at the bottom of the stilling weir, and the stilling weir reduces the scouring effect of the water flow on the downstream river channel during the flood season.

[0016] The stilling weir is provided with a stilling pier.

[0017] Beneficial effects: The water-dividing lining structure of the present invention enables the underground river to be diverted through the karst tunnel according to the dry season and the flood season. The V-shaped inverted siphon water supply pipeline is buried at a shallow depth, and there is no need to adjust the water flow gradient of the underground river. In addition, the V-shaped inverted siphon water supply pipeline solves the problem of silt accumulation on the upstream side of the lining structure in the upstream karst tunnel. At the same time, the water diversion weir reduces the impact load of the water flow on the lining structure during the flood season, so that the upper and lower diverted water loads achieve a certain degree of balance. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a front view of the present invention;

[0019] Figure 2 It is an overall diagram of the present invention;

[0020] Figure 3 A top view of the present invention;

[0021] Figure 4 This is a schematic diagram of the V-shaped inverted siphon water pipeline of the present invention.

[0022] Figure 5 Schematic diagram of the water distribution system of the present invention,

[0023] Figure 6 is a schematic diagram of a trash rack according to the present invention,

[0024] Figure 7 It is a diagram of the force dissipation system of the present invention;

[0025] The figure includes: sedimentation tank 1, trash rack 2, water diversion weir 3, eight-shaped embedded ground anchor plate foundation 4, open overflow channel 5, wear-resistant rubber belt 6, two waterproof doors 7, porous box culvert type V-shaped inverted siphon water supply pipeline 8, stilling weir 9, and stilling pier 10. DETAILED DESCRIPTION

[0026] When an underground river and a tunnel intersect, the traditional structural arrangement either passes through the lower part of the karst tunnel or the upper part of the karst tunnel, which will lead to a series of problems such as poor water flow, sedimentation, anti-floating of the lining structure and flood impact. The present invention discloses a karst tunnel and an underground river intersecting anti-siltation and anti-impact water-dividing lining structure. The structure utilizes an upstream water diversion weir, a downstream force dissipation weir, a porous box culvert-type V-shaped inverted siphon water pipe and an open overflow channel integrated with the lining structure, so that the karst tunnel lining structure divides the underground river intersecting therewith into upper and lower water-passing sections. The lower water-passing section is a porous box culvert-type V-shaped inverted siphon water pipe, which mainly serves as a water-passing channel in the dry season and prevents siltation and sand flushing in the upstream section of the karst tunnel; the upper water-passing section is an open overflow channel, which mainly serves as a water-passing channel in the flood season and prevents siltation and sand flushing in the downstream section of the karst tunnel. The water-dividing lining structure of the present invention allows the underground river to be diverted through the karst tunnel according to the dry season and the flood season. The V-shaped inverted siphon water supply pipeline is buried at a shallow depth, and there is no need to adjust the water flow gradient of the underground river. In addition, the V-shaped inverted siphon water supply pipeline solves the problem of silt accumulation on the upstream side of the lining structure when crossing the karst tunnel. At the same time, the water diversion weir reduces the impact load of the water flow on the lining structure during the flood season, so that the upper and lower diverted water loads achieve a certain degree of balance.

[0027] The present invention will be further described below with reference to the accompanying drawings and implementation examples.

[0028] To make the objectives, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention and the accompanying drawings. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts shall fall within the scope of protection of the present invention.

[0029] With reference to the accompanying drawings, the present invention provides a silt-proof and anti-impact water diversion structure for the intersection of a karst tunnel and an underground river, comprising a sedimentation tank 1, a trash rack 2, a diversion weir 3, an eight-shaped embedded ground anchor plate foundation 4, an open overflow channel 5, a wear-resistant rubber belt 6, two waterproof doors 7, a porous box culvert type V-shaped inverted siphon water supply pipeline 8, a stilling weir 9, and a stilling pier 10. The water inlet is connected to the sedimentation tank 1. The trash rack 2 is built into the sedimentation tank 1 and is located in front of the porous box culvert type V-shaped inverted siphon water supply pipeline 8. The diversion weir 3 is close to the upstream side of the lining structure, connected to the edge of the sedimentation tank 1, and connected to the open overflow channel 5 and the porous box culvert type V-shaped inverted siphon water supply pipeline 8; the porous box culvert type V-shaped inverted siphon water supply pipeline 8 connects the sedimentation tank 1 upstream and the stilling weir 9 downstream. A wear-resistant rubber belt 6 containing shock-absorbing beads is installed between the water-facing surface of the porous box culvert V-shaped inverted siphon water supply pipeline 8 and the open overflow channel 5. A wear-resistant rubber belt 6 containing shock-absorbing beads is also installed at the connection between the diversion weir 3 and the water inlet of the porous box culvert V-shaped inverted siphon water supply pipeline 8. The two waterproof gates 7 are located above the porous box culvert V-shaped inverted siphon water supply pipeline 8 downstream of the lining structure. The stilling weir 9 is located immediately downstream of the lining structure, connecting the porous box culvert V-shaped inverted siphon water supply pipeline 8 and the open overflow channel 5. The stilling weir 9 includes a stilling pier 10.

[0030] In the present invention, the water inlet, grit chamber 1, trash rack 2, and diversion weir 3 collectively constitute a water diversion system. Water flows through the water inlet into the grit chamber 1, where silt settles. Debris in the water is filtered through the trash rack 2. During the dry season, the filtered water flows through the diversion weir 3 and enters the porous box culvert V-shaped inverted siphon water supply pipeline 8. During flood season, the filtered water flows through the diversion weir 3 and enters the porous box culvert V-shaped inverted siphon water supply pipeline 8 and the open overflow channel 5.

[0031] In the present invention, the stilling weir 9 and stilling pier 10 together constitute a stilling system. Water flows through the porous box culvert V-shaped inverted siphon water pipe 8 or the open overflow channel 5 into the stilling weir 9. After passing through the stilling pier 10, the scouring force of the water flow is weakened, achieving a certain degree of balance between the upper and lower water loads.

[0032] In the present invention, the porous box culvert type V-shaped inverted siphon water supply pipeline 8 is buried shallowly and does not need to adjust the water flow gradient of the underground river. It can solve the problem of silt accumulation on the upstream side of the lining structure of the upstream karst tunnel.

[0033] In the present invention, the porous box culvert type V-shaped inverted siphon water supply pipeline 8 has the function of preventing siltation and sand flushing of the water channel and the upstream section of the karst tunnel during the dry season; the open overflow channel 5 has the function of preventing siltation and sand flushing of the water channel and the downstream section of the karst tunnel during the flood season.

[0034] In the present invention, the porous box culvert V-shaped inverted siphon water pipe 8 and the open overflow channel 5 both serve as water passages. During flood seasons, when water flow is high, water flows through both the porous box culvert V-shaped inverted siphon water pipe 8 and the open overflow channel 5, converges at the stilling weir 9, and then passes through the stilling pier 10 to reduce the scouring force of the water flow. During dry seasons, when water flow is low, water flows through the porous box culvert V-shaped inverted siphon water pipe 8 and enters the stilling weir 9, where the scouring force of the water flow is reduced by the stilling pier 10.

[0035] In the present invention, the construction joints and expansion joints of the lining structure are not arranged within the width of the underground river.

Claims

1. A silt-proof and anti-scour water-dividing structure for the intersection of a karst tunnel and an underground river, characterized by: The structure comprises a sedimentation tank (1), a trash rack (2), a water diversion weir (3), an eight-shaped embedded ground anchor plate foundation (4), an open overflow channel (5), a wear-resistant rubber belt (6), two waterproof doors (7), a porous box culvert type V-shaped inverted siphon water supply pipeline (8), a force dissipation weir (9), and a force dissipation pier (10); the structure is supported by an eight-shaped embedded ground anchor plate foundation (4), a porous box culvert type V-shaped inverted siphon water supply pipeline (8) is provided on the eight-shaped embedded ground anchor plate foundation (4), and two waterproof doors (7) are provided on the porous box culvert type V-shaped inverted siphon water supply pipeline (8). ), an open overflow channel (5) is provided on both sides of the two waterproof doors (7); the upstream of the open overflow channel (5) is an upper water-passing section, a sedimentation tank (1) is provided upstream of the open overflow channel (5), a trash rack (2) is provided in the sedimentation tank (1), a water diversion weir (3) is provided on the right side of the trash rack (2), and a wear-resistant rubber belt (6) is provided at the connection between the water diversion weir (3) and the water inlet of the porous box culvert type V-shaped inverted siphon water supply pipeline (8); the downstream of the open overflow channel (5) is a lower water-passing section, and a stilling weir (9) is provided downstream of the open overflow channel (5); In the water-dividing structure, the upstream water diversion weir (3), the downstream force dissipation weir (9), the porous box culvert type V-shaped inverted siphon water delivery pipe (8) and the open overflow channel (5) enable the karst tunnel structure to divide the underground river intersecting therewith into upper and lower water-passing sections; the lower water-passing section is the porous box culvert type V-shaped inverted siphon water delivery pipe (8), which mainly serves as a water-passing channel in the dry season and prevents siltation and sand flushing in the upstream section of the karst tunnel; the upper water-passing section is the open overflow channel (5), which mainly serves as a water-passing channel in the flood season and prevents siltation and sand flushing in the downstream section of the karst tunnel; In the water diversion structure, the sedimentation tank (1) is located at the front end of the upstream side of the water diversion structure; the stilling weir (9) is located at the rear end of the downstream side of the water diversion structure; the trash rack (2) is located in the sedimentation tank (1) and in front of the water inlet of the porous box culvert type V-shaped inverted siphon water supply pipeline (8); the water diversion weir (3) is located on the upstream side close to the outside of the water diversion structure and connected to the edge of the sedimentation tank (1); the stilling weir (9) is located on the downstream side close to the outside of the water diversion structure; the porous box culvert type V-shaped inverted siphon water supply pipeline (8) passes through the bottom of the karst tunnel structure and connects the upstream sedimentation tank (1) and the downstream stilling weir (9); two waterproof doors (7) constitute an inspection door channel and are placed above the V-shaped inverted siphon water supply pipeline (8); In the water diversion structure, during the dry season, the underground river water flows only from the porous box culvert type V-shaped inverted siphon water pipe (8) to pass through the karst tunnel, and the water-binding effect of the porous box culvert type V-shaped inverted siphon water pipe (8) flushes away the sediment at the bottom of the pipe during the flood season; during the flood season, the underground river water flows through the two water passages of the porous box culvert type V-shaped inverted siphon water pipe (8) and the open overflow channel (5) to pass through the karst tunnel, and takes away the sediment in the porous box culvert type V-shaped inverted siphon water pipe (8) and the bottom of the open overflow channel (5), and the stilling weir (9) reduces the flushing effect of the water flow on the downstream river channel during the flood season.

2. The anti-siltation and anti-scour water diversion structure for the intersection of a karst tunnel and an underground river according to claim 1, characterized in that: In the water diversion structure, an eight-shaped embedded ground anchor plate foundation (4) is adopted, and a segmented annular reinforced grid frame structure along the outer side of the structure in the longitudinal direction of the tunnel is used as a water diversion structure load-bearing reinforcement member, which is separated from the porous box culvert type V-shaped inverted siphon water supply pipeline (8) and serves as a vertical force transmission member for the water diversion weir (3) and the force dissipation weir (9).

3. The anti-siltation and anti-scour water diversion structure for the intersection of a karst tunnel and an underground river according to claim 1, characterized in that: In the water diversion structure, a wear-resistant rubber belt (6) containing vibration-damping beads is arranged on the water-facing surface of the water passage; a wear-resistant rubber belt (6) containing vibration-damping beads is arranged at the connection between the water diversion weir (3) and the water inlet of the porous box culvert type V-shaped inverted siphon water pipe (8), forming an anti-impact and anti-seepage structure.

4. The anti-siltation and anti-scour water diversion structure for the intersection of a karst tunnel and an underground river according to claim 1, characterized in that: The stilling weir (9) is provided with a stilling pier (10).

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