A treatment method for tunnel collapse and water inrush

Abstract

The present invention discloses a method for treating tunnel collapse and water inrush, which relates to the technical field of tunnel engineering. The method is as follows: drilling and sampling, using a drilling and sampling device to drill and sample the planned tunnel route, and the sampling depth is 30-50 meters. When the tunnel reaches two-thirds of the sampling depth. Through the setting of this treatment method, when tunnel collapse and water inrush occur, the adjacent non-collapsed areas are reinforced and drained immediately, and only when the water level height inside the tunnel is lower than the set height can the following steps be carried out. By reinforcing the collapsed area and repairing the collapsed area, the possibility of the outer layer material of the collapsed area collapsing into the collapsed area is reduced during the cleaning of crushed stones and soil, ensuring construction safety. When a water leakage point is found, it is blocked by plugging water, which can effectively treat tunnel collapse and water inrush and reduce the possibility of secondary collapse.

Description

Technical Field

[0001] The present invention relates to the technical field of tunnel engineering, and specifically to a method for treating tunnel collapse and water inrush. Background Technique

[0002] In water conservancy projects, in order to convey water or discharge flood, closed water conveyance channels are often excavated through mountains, which are called hydraulic tunnels. Water inrush, also known as sudden water inrush, refers to the sudden large amount of water inrush that occurs during the construction of underground chambers and roadways when passing through areas with developed karst caves, especially when encountering underground river systems, thick water-bearing sand and gravel layers, and large fracture zones connected to surface water. The groundwater (pore water source, fissure water source, karst water source) and surface water source in the ore body and surrounding rock voids gush out under the action of pressure, which is called water inrush.

[0003] During the use or construction of a tunnel, tunnel collapse may occur, and the collapse may be related to groundwater activities. Therefore, the situation of simultaneous occurrence of tunnel collapse and water inrush may occur. For this reason, a method for treating tunnel collapse and water inrush is proposed. Summary of the Invention

[0004] The purpose of the present invention is to provide a method for treating tunnel collapse and water inrush to solve the problems raised in the above background technique.

[0005] To achieve the above purpose, the present invention provides the following technical solution: A method for treating tunnel collapse and water inrush, the method is as follows:

[0006] Drill and sample, use a drill sampling device to drill and sample the planned tunnel route, the sampling depth is 30 - 50 meters, and when the tunnel reaches two-thirds of the sampling depth, use the drill sampling device again for sampling, and drain the soil layer.

[0007] Reinforce the adjacent non-collapsed areas, reinforce the 5 - 10-meter tunnel area connected to the collapsed area, reinforce the inside of the support lining through a steel arch support, install a steel arch support inside the support lining, and connect the steel arch supports through reinforcing bars.

[0008] Drain water, adopt a stepped drainage method, install a water pump every 500 - 600 meters along the tunnel, one end of the water pump is provided with a water pipe, and a water tank is provided on one side of the water pump. The following steps can be carried out only when the water level height inside the tunnel is one-tenth or less of the internal height of the tunnel.

[0009] Clean the crushed stones and soil and reinforce the collapsed area. Install several fixed anchor rods along the inner wall edge of the support lining in the non-collapsed area towards the collapsed area. The fixed anchor rods are located inside the steel arch support. The installation of the fixed anchor rods starts from the top of the steel arch support and ends at the bottom. The length of the installed fixed anchor rods is 6 - 10 meters. The length of the fixed anchor rods in the non-collapsed area is two-fifths of the total length, and the length in the collapsed area is three-fifths of the total length. The fixed anchor rods are grouting anchor rods, and grout is injected through the grouting anchor rods to the edge position of the collapsed area. The grout is cement slurry. After the cement slurry cools and fixes, clean the crushed stones. The cleaning of the crushed stones is carried out from the top to the bottom inside the tunnel. The crushed stones to be cleaned are located in the inner area of several fixed anchor rods. When the depth of cleaning the crushed stones and soil is two-fifths of the length of the fixed anchor rods, install fixed anchor rods again on the reinforced inner wall of the collapsed area;

[0010] Repair of the collapsed area. When cleaning the crushed stones and soil, temporarily reinforce the collapsed area at the same time. A wire mesh is installed between the collapsed area and the outer wall of the steel arch support;

[0011] Water blocking. When cleaning the crushed stones and soil and repairing the collapsed area, when encountering a water leakage position, carry out grouting to block water;

[0012] The tunnel structure includes a support lining. On one side of the inner bottom of the support lining, there is a water passage. The top of the water passage is fixedly connected with a protective plate, and water passing holes are opened at the top of the protective plate.

[0013] Furthermore, when reinforcing the adjacent non-collapsed area, the length of the reinforcement is positively correlated with the size of the cross-section of the tunnel. The outer wall of the steel arch support is adapted to the inner wall of the support lining.

[0014] Furthermore, there is a quick-setting agent inside the cement slurry. The fixed anchor rods are grouted using a grouting machine, and the fixed anchor rods are installed using a rock drill.

[0015] Furthermore, for cleaning the crushed stones, mainly use a rock drill to break them and use weak blasting as an auxiliary. When cleaning the crushed stones, a rock drill is needed to break large stones, and the crushed stones and soil are transported by a transport device.

[0016] Furthermore, when blocking water, when the water pumping volume of a single water pump per unit time is less than three-fifths of the rated water pumping volume of the water pump, carry out water blocking.

[0017] Furthermore, the repair of the collapsed area includes installing grouting anchor rods and building a support lining. For every 0.2 - 0.3 meters of crushed stones and soil cleaned, build a support lining with a width of 0.2 - 0.3 meters.

[0018] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0019] For the method for treating tunnel collapse and water inrush, through the setting of this treatment method, when a tunnel collapse and water inrush occur, the adjacent non-collapsed areas are reinforced and drained immediately. And only when the water level inside the tunnel is lower than the set height can the following steps be carried out. By reinforcing and repairing the collapsed area, the possibility of the outer layer material of the collapsed area collapsing into the collapsed area is reduced during the cleaning of gravel and soil, ensuring construction safety. When a water leakage point is found, it is blocked by a water plugging method, which can effectively treat tunnel collapse and water inrush and reduce the possibility of secondary collapse. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a cross-sectional view of the tunnel structure of the present invention;

[0021] Figure 2 It is a schematic diagram of the reinforcement and repair of the collapsed area of the present invention;

[0022] Figure 3 It is a schematic diagram of the reinforcement and repair of the collapsed area of the present invention.

[0023] In the figure: 1, support lining; 2, water passage; 3, protection plate; 4, grouting bolt; 5, steel arch support. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0024] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0025] It should be noted that in the description of the present invention, the orientation or positional relationship indicated by the terms "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. is based on the orientation or positional relationship shown in the accompanying drawings. It is only for the convenience of describing the present invention and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation to the present invention.

[0026] In addition, it should be understood that for the convenience of description, the dimensions of each component shown in the accompanying drawings are not drawn according to the actual proportional relationship. For example, the thickness or width of some layers may be exaggerated relative to other layers.

[0027] It should be noted that similar reference numerals and letters indicate similar items in the following drawings. Therefore, once an item is defined or described in one drawing, it will not require further specific discussion and description in the descriptions of subsequent drawings.

[0028] As Figure 1 - Figure 3 shown, the present invention provides a technical solution: a method for treating tunnel collapse and water inrush, and the method is as follows:

[0029] Drill for sampling. Using a drill sampling device, drill for sampling along the planned tunnel route. The sampling depth is 30 - 50 meters. When the tunnel reaches two-thirds of the sampling depth, use the drill sampling device again for sampling, and drain the soil layer.

[0030] Reinforce the adjacent non-collapsed areas. Reinforce the 5 - 10-meter tunnel area connected to the collapsed area. Reinforce the inside of the support lining 1 through the steel arch support 5. By installing the steel arch support 5 inside the support lining 1, the steel arch supports 5 are connected by reinforcing bars.

[0031] Drainage. Adopt a stepped drainage method. Install water pumps every 500 - 600 meters along the tunnel. One end of the water pump is provided with a water pipe, and a water tank is provided on one side of the water pump. The following steps can only be carried out when the water level height inside the tunnel is one-tenth or less of the internal height of the tunnel.

[0032] Clean the crushed stones and soil and reinforce the collapsed area. Install a number of fixed anchor bolts along the inner wall edge position of the support lining 1 of the non-collapsed area towards the collapsed area. The fixed anchor bolts are located inside the steel arch support 5. The fixed anchor bolts are installed starting from the top of the steel arch support to the bottom of the steel arch support 5. The length of the installed fixed anchor bolts is 6 - 10 meters. The length of the fixed anchor bolts in the non-collapsed area is two-fifths of the total length, and the length in the collapsed area is three-fifths of the total length. The fixed anchor bolts are grouting anchor bolts 4. Grout towards the edge position of the collapsed area through the grouting anchor bolts 4. The grout is cement slurry. After the cement slurry cools and fixes, clean the crushed stones. The crushed stones are cleaned from the top to the bottom inside the tunnel. The cleaned crushed stones are located in the internal area of a number of fixed anchor bolts. When the depth of cleaning the crushed stones and soil is two-fifths of the length of the fixed anchor bolts, install fixed anchor bolts again on the reinforced inner wall of the collapsed area.

[0033] Repair of the collapsed area. When cleaning the crushed stones and soil, simultaneously conduct temporary reinforcement treatment on the collapsed area. Install a wire mesh between the collapsed area and the outer wall of the steel arch support 5.

[0034] Water plugging. When cleaning the crushed stones and soil and repairing the collapsed area, when encountering a water leakage position, conduct grouting for water plugging.

[0035] The tunnel structure includes a support lining 1. On one side of the inner bottom of the support lining 1, there is a water passage 2. The top end of the water passage 2 is fixedly connected with a protective plate, and water passing holes are opened at the top end of the protective plate.

[0036] When strengthening adjacent non-collapsed areas, the length of the reinforcement is positively correlated with the size of the cross-section of the tunnel. The outer wall of the steel arch support 5 is adapted to the inner wall of the support lining 1.

[0037] There is a quick-setting agent inside the cement slurry. The fixed anchor rods are grouted using a grouting machine, and the fixed anchor rods are installed using a rock drill.

[0038] Clean the crushed stones. Mainly use a rock drill to break them, supplemented by weak blasting. To clean the crushed stones, a rock drill needs to be used to break large stones, and the crushed stones and soil are transported through a transportation device.

[0039] When plugging water, if the water pumping volume of a single water pump per unit time is less than three-fifths of the rated water pumping volume of the water pump, water plugging is carried out.

[0040] The repair of the collapsed area includes installing grouting anchor rods 4 and building a support lining 1. For every 0.2 - 0.3 meters of crushed stones and soil cleared, a support lining 1 with a width of 0.2 - 0.3 meters is built.

[0041] When dealing with the collapse, the anti-drainage work should be strengthened. Collapses are often related to groundwater activities. To control collapses, water should be treated first. In the actual use process of the tunnel, tunnel collapses and water inrushes may occur simultaneously. Therefore, the treatment of collapses and water inrushes needs to be carried out simultaneously. Tunnel water inrush is a dynamic failure phenomenon caused by the destruction of the aquifer structure during the tunnel construction process, which changes the hydrodynamic conditions and the mechanical equilibrium state of the surrounding rock, resulting in the instantaneous release of the energy stored in the underground water body in the form of fluid.

[0042] When it cannot be ensured that there is no threat of water damage, borehole sampling should be carried out along the planned route of the tunnel to further explore the hydrogeological conditions. This is an important measure to prevent sudden water inrush. The water source can be drained and plugged in advance to reduce the water source pressure, which can effectively prevent collapses and water inrush in the subsequent use of this area due to this water source. By using borehole sampling to sample the soil layer where the tunnel has not been built, the structure of the soil layer can be determined. When encountering a water source during borehole sampling, the water source can be drained to reduce the water pressure, which can effectively reduce the occurrence of collapses or water inrush caused by this water source during the subsequent use. When the water source pressure decreases, the water source can be plugged. The size of the water source pressure can be judged according to the pumping volume of a single water pump. During the plugging process, the water pressure of the leakage gap may be too high. Since the pumping volume of a single water pump is used to judge the water inrush volume, the excessive water pressure of this gap is mainly caused by the too small size of the gap. For this area, the plugging method can be directly used for sealing. By borehole sampling, the structure of the soil layer where the tunnel has not been built can be determined. Draining the water source can ensure the subsequent use of the tunnel. When carrying out borehole sampling, refer to the sampling finished products. The types and humidity of the samples determine whether to build the tunnel along this route.

[0043] After the tunnel collapses, the uncollapsed section should be reinforced first to prevent the collapse cavity from expanding, especially the tunnel area connected to the collapse area. The steel arch support 5 is used for support and reinforcement. The steel arch support 5 has been produced and completed at the beginning of the tunnel construction. After the tunnel collapses, the steel arch support 5 can be directly used, which can support and reinforce the tunnel area connected to the collapse area in the shortest time and can effectively prevent the continuous expansion of the collapse. The steel arch supports 5 are fixed by reinforcing bars. Whether the volume of the collapse is small or large, the use of the steel arch support 5 requires more than the tunnel area connected to the collapse area for support and reinforcement, which can avoid secondary collapses.

[0044] Multiple collapses have caused damage to the side walls and the top of the support lining 1, while the bottom of the support lining 1 is at most cracked. By arranging the water channel 2 and the protective plate 3 on one side of the inner bottom of the support lining 1, due to the setting of the support lining 1, the possibility of damage at the angle of the support lining 1 is reduced, which can protect the water channel 2 and the protective plate 3. The protective plate 3 can protect the water channel 2. When water gushes out, insert a water pipe into the inside of the water channel 2 and move through the water channel 2 to the water channel 2 in the collapse area to drain the collapse area. The protective plate 3 is detachably installed. If the protective plate 3 is damaged and the inside of the water channel 2 in the collapse area is filled with gravel and soil, then the water in the collapse area can only be drained outside the collapse area. The number of drainage pumps can be arranged according to the water gushing volume. At the beginning of the tunnel collapse and water gushing, without knowing the water gushing volume, all the pumps are used. Subsequently, as the water level drops and the water gushing volume decreases, the number of pumps can be appropriately reduced. A filter screen is fixedly connected to one end of the water pipe. The use of the filter screen can effectively prevent gravel from entering the pump, resulting in damage to the pump and affecting the efficiency of the pump. The length of the water pipe during drainage is related to the vertical height between two adjacent pumps. When the pump transports water from a lower place to a higher place, the required water pipe length is short. When the pump transports water from a lower place to a lower place, the required water pipe length is long. The number of pumps and water pipes can be increased according to actual needs to ensure that the water level inside the tunnel can quickly drop to one-tenth of the height inside the tunnel.

[0045] Reinforcing the adjacent non-collapsed areas and drainage need to be carried out simultaneously, and the following steps can only be carried out when the water level line height inside the tunnel is one-tenth or less of the height inside the tunnel. When the water level line height inside the tunnel is lower than the set height, the water gushing volume inside the tunnel decreases, the water gushing pressure at the water gushing place inside the tunnel decreases, and the possibility of secondary collapse of the tunnel decreases.

[0046] Obstacles such as crushed stones and soil block the tunnel and cannot be directly cleared. First, use a drilling machine to drill holes from the inner wall edge position of the support lining 1 in the non-collapse area towards the collapse area. After the drilling is completed, it is necessary to penetrate the water gushing situation. If there is no water gushing, the grouting anchor rod 4 can be directly installed, and then grouting is carried out through the grouting anchor rod 4. The rod body of the grouting anchor rod 4 is designed with a hollow structure, and the middle hole of the rod body serves as the drilling high-pressure air and water channel and the grouting channel. Compared with the solid rod body, the hollow rod body design can obtain better stiffness and shear strength. The outer surface of the anchor rod body has a standard large-pitch thread structure throughout its length. The thread structure is convenient for cutting and extending the anchor rod. Compared with the smooth rod body, it increases the bonding area between the anchor rod body and the grouting material, thereby improving the anchoring force. After the cement slurry cools and solidifies, the crushed stones and soil within the area surrounded by multiple grouting anchor rods 4 are cleared. When clearing the crushed stones and soil, when the force exerted by the outer layer area of the collapse area on the crushed stones and soil is borne by the grouting anchor rods 4 and the cooled cement, the collapse area is reinforced while clearing the crushed stones. The reinforcement method is to reinforce the collapse area by constructing the support lining 1. During the construction of the support lining 1, the grouting anchor rods 4 and the cooled cement are wrapped, making the support lining 1, the grouting anchor rods 4, and the cement integrated. Before constructing the support lining 1, the grouting anchor rods 4 are installed outside the collapse area. The grouting anchor rods 4 can not only support the collapse area but also block the flowing water. When installing and fixing the anchor rods, the positions of two adjacent batches of fixed anchor rods are staggered.

[0047] When clearing the crushed stones, use a rock drill to crush the large stones and transport the stones and soil outside the tunnel. Since the rock drill can drill holes, when drilling holes in the large stones, the large stones can be crushed by the number of drill holes and the drilling depth. When clearing the crushed stones, the collapse can be gradually cleared from both ends or one end first from top to bottom. During the clearing process, pay attention to observing whether there is a possibility of changes in the surrounding rock of the vault and the periphery to avoid secondary collapses.

[0048] At the same time, use the rock drill to drill holes and clean the holes, insert the grouting anchor rod 4 with the anchor head installed into the hole, and the barbs on the anchor head immediately hook the anchor rod. Install the grout stopper, backing plate, nut, and connect the grouting machine: Connect the tail end of the anchor rod and the selected grouting machine through a quick grouting joint, and grout: Start the machine to grout. If pressure grouting is required to improve the surrounding rock structure, just wait until the pointer on the pressure gauge rises to the design pressure.

[0049] When plugging the water leakage location, the water discharge volume at the water gushing location determines whether to plug it immediately. When the water discharge volume at the water gushing location is too large, it means that the water pressure at this location is too high. Immediately plugging will cause the plugging slurry to be washed out of the water leakage location under the action of water pressure. Therefore, it is necessary to wait until the water pressure at the water gushing location becomes smaller before plugging can be carried out. It can be judged according to the water flow rate when the water pump is pumping water. When the water flowing out of the tunnel is less, it means that the water pressure at the water gushing location is small. On the contrary, the larger it is. The pumping power of the water pump is fixed. In the early stage, the water pumping volume per unit time of the water pump is fixed. As the pumping time increases, the water gushing volume per unit time is lower than the water pumping volume of the water pump. At the same time, due to the continuous reduction of water, the water gushing volume will also slowly decrease. When the water pumping volume per unit time of the water pump is lower than the rated water pumping volume of the used water pump, the gap can be plugged at this time, and the plugging is carried out by means of grouting.

[0050] For large stones, mainly use rock drills to break them and supplemented by weak blasting. In the actual process, only large and difficult-to-carry stones are processed in the above way. Try not to use blasting if possible to reduce the possibility of secondary collapse caused by blasting.

[0051] Through the setting of this treatment method, when a tunnel collapses and water gushes out, the adjacent uncollapsed areas are reinforced and drained immediately. And only when the water level height inside the tunnel is lower than the set height can the following steps be carried out. By strengthening the collapsed area and repairing the collapsed area, when cleaning the crushed stones and soil, the possibility of the outer layer material of the collapsed area collapsing into the collapsed area is reduced, ensuring the construction safety. When a water leakage point is found, it is blocked by means of water plugging, which can effectively treat the tunnel collapse and water gushing, and reduce the possibility of secondary collapse.

[0052] Although the embodiments of the present invention have been shown and described, for those of ordinary skill in the art, it can be understood that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principle and spirit of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A method for treating tunnel collapse and water gushing, characterized by: The method is as follows: Drilling sampling: using a drilling sampling device, drilling samples along the planned tunnel route, the sampling depth is 30-50 meters. When the tunnel construction reaches two-thirds of the sampling depth, the drilling sampling device is used again to sample and drain the soil layer; Reinforce the adjacent non-collapsed area, reinforce the tunnel area connected to the collapsed area by 5-10 meters, reinforce the interior of the support lining (1) by using steel arch support brackets (5), and install steel arch support brackets (5) inside the support lining (1), and connect the steel arch support brackets (5) with reinforced steel bars; Drainage is carried out in a stepped manner, with water pumps installed every 500-600 meters along the tunnel. A water pipe is installed at one end of the water pump, and a water tank is installed on one side of the water pump. The following steps can only be carried out when the water level inside the tunnel is one-tenth of the tunnel's internal height or less; Cleaning gravel and soil and reinforcing the collapsed area, installing several fixed anchor rods along the inner edge of the supporting lining (1) in the non-collapsed area to the collapsed area, the fixed anchor rods being located inside the steel arch support (5), the method of installing the fixed anchor rods starting from the top of the steel arch support to the bottom of the steel arch support (5), the length of the fixed anchor rods installed being 6-10 meters, the length of the fixed anchor rods located in the non-collapsed area being two-fifths of the total length, and the length of the fixed anchor rods located in the collapsed area being three-fifths of the total length, the fixed anchor rods being grouting anchor rods (4), grouting being performed toward the edge of the collapsed area through the grouting anchor rods (4), the slurry being cement slurry, and after the cement slurry is cooled and fixed, cleaning the gravel, the cleaning of the gravel is performed from the top of the tunnel to the bottom of the tunnel, the cleaned gravel being located in the inner area of several fixed anchor rods, and when the depth of the cleaned gravel and soil is two-fifths of the length of the fixed anchor rods, installing the fixed anchor rods again on the reinforced inner wall of the collapsed area; Repair of the collapsed area, while clearing the gravel and soil, temporarily reinforcing the collapsed area, with a wire mesh installed between the collapsed area and the outer wall of the steel arch support (5); Water blocking: when clearing gravel and soil and repairing landslide areas, grouting is performed to block water leaks; The tunnel structure comprises a supporting lining (1), a water channel (2) is provided on one side of the bottom of the supporting lining (1), a top end of the water channel (2) is fixedly connected to a protective plate, and a water hole is provided at the top end of the protective plate; When reinforcing the adjacent non-collapsed area, the length of the reinforcement is positively correlated with the size of the tunnel cross section, and the outer wall of the steel arch support (5) is adapted to the inner wall of the support lining (1).

2. A method for treating tunnel collapse and water gushing according to claim 1, characterized in that: The cement slurry contains a quick-setting agent, the fixed anchor rod is grouted using a grouting machine, and the fixed anchor rod is installed using a rock drill.

3. The method for treating tunnel collapse and water gushing according to claim 1, characterized in that: The gravel cleaning method mainly uses rock drill to crush the large stones, and weak blasting is used as a supplement. The gravel cleaning method requires using rock drill to crush large stones, and the gravel soil is transported by a transportation device.

4. The method for treating tunnel collapse and water gushing according to claim 1, characterized in that: During the water blocking, water blocking is performed when the water pumping capacity of a single water pump is lower than three-fifths of the rated water pumping capacity of the water pump within a unit time.

5. The method for treating tunnel collapse and water gushing according to claim 1, characterized in that: The repair of the collapsed area includes installing grouting anchor rods (4) and constructing a supporting lining (1). For every 0.2-0.3 meters of gravel and soil cleared, a supporting lining (1) with a width of 0.2-0.3 meters is constructed.

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