A method for arranging tunnel intersections for compressed gas energy storage in abandoned shaft and tunnel space

Abstract

The present invention provides a method for arranging tunnel intersections for compressed gas energy storage in abandoned shaft and tunnel spaces, and relates to the technical field of shaft and tunnel utilization. The method includes: using geophysical detection methods to conduct preliminary detection of tunnel intersections, determine the stress and deformation state of the tunnel surrounding rock at the tunnel intersection, and determine the range of the elastic-plastic zone; divide the tunnel intersection into multiple areas; dig equilateral triangle grooves on both sides of the tunnel; reinforce the tunnel surrounding rock by grouting and grouting anchors; set a ventilation pipe in the middle of the tunnel, and set a three-way valve in the intersection area of ​​the tunnel, and wrap a protective layer on the outside of the ventilation pipe; fill and seal according to the regional division. This method can effectively reduce the difficulty of management through regional grouting reinforcement management, and also improve the bearing capacity of the tunnel. It uses connecting pipes to connect multiple tunnels to ensure smooth gas circulation; in addition, the tunnel intersections set by this method have better airtightness and stability, which provides convenience for compressed gas energy storage.

Description

Technical Field

[0001] The invention relates to the technical field of shaft and tunnel utilization, and in particular provides a method for arranging tunnel intersections for compressed gas energy storage in abandoned shaft and tunnel spaces. Background Art

[0002] New energy (such as wind energy and solar energy) is an ideal alternative energy source because of its rich resources, wide distribution, renewable nature, and environmental friendliness. However, the uncertainty and uncontrollability of wind power and photovoltaic power have resulted in the inability of wind turbines connected to the power grid to meet the requirements of stability, continuity, and adjustability. The constant change in output power can easily impact the power grid, and the dispatching and operating personnel are unable to make effective power generation plans for wind power generation, which in turn leads to an increase in system backup power, peak-shaving capacity, and system operating costs, threatening the safe and stable operation of the system. Compressed air energy storage technology can better solve the intermittent and instability problems of clean energy generation. By using its dual regulation function, it can better enhance the peak-shaving capacity of the power grid. The use of compressed air energy storage technology can be an effective means of regulating power supply and reusing abandoned mines.

[0003] With the further advancement of coal mine production reduction, a large number of abandoned shafts and tunnels are left in abandoned mines. Rational use of underground space, avoiding waste of space resources, and realizing the reuse of abandoned mines are issues that need to be urgently addressed today. Using abandoned shafts and tunnels as compressed gas energy storage space and building compressed gas energy storage power stations can, on the one hand, effectively utilize a large amount of abandoned underground space; on the other hand, the development of compressed air energy storage technology also further promotes the development of renewable energy. In the operation of compressed gas energy storage power stations, abandoned shafts and tunnels play an important role as storage space for high-pressure air. The key issue in its construction is the sealing of abandoned shafts and tunnels as gas storage space and the stability of surrounding rocks.

[0004] In the prior art, Chinese patent CN106593486A discloses a steel tube concrete composite support for tunnel intersections. The invention connects the support frame and the lap frame through a docking device and injects concrete slurry to form a steel tube concrete structure for overall support. This method does not take into account the influence of parts such as casing and grouting ports on the overall strength of the composite support during the treatment process; and this method does not consider the airtightness problem at the tunnel intersection, and cannot guarantee the airtightness at the tunnel intersection, and cannot be well applied to the treatment of tunnel intersections for compressed gas energy storage in abandoned shaft and tunnel space.

[0005] Chinese patent CN 203374284U discloses a fully enclosed section masonry support for soft rock tunnels, which uses anchor rods and steel mesh sprayed concrete layer anchor mesh spraying support as the primary support, the inner layer of masonry constitutes a horseshoe-shaped section composite support, and the anti-bottom arch is poured and backfilled with gangue to form a fully enclosed complete support. Although this support method forms a closed support space, its sealing performance is poor and cannot meet the use requirements of compressed gas energy storage utilization in abandoned shaft and tunnel space.

[0006] The existing methods for managing tunnel intersections are generally combined support and anchor mesh support. These methods all provide support for tunnel intersections and play a good supporting and protective role; but they do not take into account the airtightness requirements when the tunnel is used as a gas storage. Because no certain treatment is done for the airtightness of the tunnel intersections, they are not suitable for the management of tunnel intersections for compressed gas energy storage in abandoned shaft and tunnel space. Summary of the invention

[0007] In order to achieve the management of tunnel intersection positions, improve the tunnel bearing capacity, and ensure the airtightness and stability of the intersection positions, the present invention provides a method for arranging tunnel intersections for compressed gas energy storage in abandoned shaft and tunnel spaces, and the specific technical scheme is as follows.

[0008] A method for arranging a tunnel intersection for compressed gas energy storage in an abandoned shaft and tunnel space, characterized in that the steps include:

[0009] S1. Use geophysical detection methods to conduct preliminary detection of the tunnel intersections, determine the stress and deformation state of the tunnel surrounding rock at the tunnel intersections, and determine the elastic-plastic zone range of the tunnel surrounding rock;

[0010] S2. Divide the roadway intersection area into multiple areas;

[0011] S3. Dig equilateral triangle grooves on both sides of the tunnel;

[0012] S4. Grouting the surrounding rock of the tunnel and constructing grouting anchor reinforcement;

[0013] S5. Set up a ventilation pipe in the middle of the tunnel, set up a three-way valve at the intersection of the tunnels, and wrap a protective layer outside the ventilation pipe;

[0014] S6. Fill and seal according to the area division.

[0015] Preferably, the geophysical exploration method includes a direct current resistivity method, an electromagnetic survey method and a gravity survey method.

[0016] Preferably, the side length of the equilateral triangle is 0.3-0.7 times the width of the lane, and the groove and the lane space form a truncated cone cavity structure.

[0017] Preferably, the tunnel surrounding rock grouting specifically involves grouting reinforcement of the plastic failure zone of the tunnel surrounding rock, and the grouting anchors fill the cracks and pores in the elastic zone of the tunnel surrounding rock.

[0018] Preferably, the protective layer includes a first PE film layer, a steel mesh layer and a second PE film layer, and the first PE film layer, the steel mesh layer and the second PE film layer are arranged in sequence from inside to outside.

[0019] It is also preferred that the filling and sealing process includes: arranging steel mesh, setting slurry retaining plates, filling and grouting with concrete, and removing the slurry retaining plates after the slurry solidifies.

[0020] It is also preferred that the filling and sealing is performed by grouting in sequence according to the multiple areas divided in step S2.

[0021] It is also preferred that when the intersection area is divided, each area does not contain an intersection, and the intersection is located at the boundary of adjacent areas.

[0022] It is further preferred that a valve is provided on the ventilation pipe, and the ventilation pipe is a hollow steel pipe.

[0023] It is further preferred that the method for arranging the intersection points of the tunnels for compressed gas energy storage in abandoned shaft and tunnel spaces can also be applied to sharp intersections or bull nose intersections.

[0024] The beneficial effect of the method for arranging tunnel intersections for compressed gas energy storage in abandoned shaft and tunnel space provided by the present invention is that the method divides the areas in detail at the tunnel intersections, and successively reinforces and manages the tunnels by dividing the areas, thereby improving the bearing capacity of the tunnels and ensuring the stability of the tunnel surrounding rocks. At the same time, the tunnels are connected by two-way pipes to ensure smooth flow of gas; the method reduces the pressure of the surrounding rocks at the tunnel intersections by making the ventilation pipe the main part that bears the gas pressure, effectively avoiding surrounding rock damage, and the method is applicable to the treatment of various types of tunnel intersection positions, has a wide range of applicability, and has good management effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a flow chart of the method for arranging the intersection of the abandoned shaft and lane space for compressed gas energy storage;

[0026] Figure 2 It is a schematic diagram of the roadway intersection;

[0027] Figure 3 It is a schematic diagram of the area division of the lane intersection;

[0028] Figure 4 It is a schematic diagram of the groove construction at the intersection of the laneway;

[0029] Figure 5 This is a schematic diagram of tunnel grouting construction;

[0030] Figure 6 This is a schematic diagram after the intersection is governed;

[0031] In the figure: 1-tunnel, 2-tunnel surrounding rock, 3-tunnel intersection, 4-groove, 5-grouting anchor, 6-grouting hole, 7-elastic zone of surrounding rock, 8-plastic zone of surrounding rock, 9-pipeline, 10-valve. DETAILED DESCRIPTION

[0032] Combination Figures 1 to 6 As shown, a specific implementation method of a method for arranging tunnel intersections for compressed gas energy storage in abandoned shaft and tunnel spaces provided by the present invention is described.

[0033] The existing methods for managing tunnel intersections are generally combined support and anchor mesh support. These methods all provide support for tunnel intersections and play a good supporting and protective role; however, these methods do not take into account the airtightness requirements when the tunnel is used as a gas storage, so they cannot do a certain treatment for the airtightness of the tunnel intersections, and are not suitable for the management of tunnel intersections for compressed gas energy storage in abandoned shaft and tunnel space.

[0034] A method for arranging a tunnel intersection for compressed gas energy storage in an abandoned shaft and tunnel space, characterized in that the steps include:

[0035] S1. Use geophysical detection methods to conduct preliminary detection of the tunnel intersections, determine the stress and deformation state of the tunnel surrounding rock at the tunnel intersections, and determine the elastic-plastic zone range of the tunnel surrounding rock;

[0036] Geophysical exploration methods include DC resistivity, electromagnetic exploration, and gravity exploration. Preliminary exploration is conducted at the intersection of the tunnels using geophysical exploration methods, and the results of the preliminary exploration are further verified by drilling to clarify the stress and deformation state of the tunnel surrounding rock at the tunnel intersection, and to explore the scope of its elastic-plastic zone, providing a theoretical basis for subsequent grouting reinforcement of the plastic damage zone of the tunnel surrounding rock and preliminary treatment of the grouting anchor cable arrangement in the elastic core zone of the tunnel surrounding rock.

[0037] S2. Divide the roadway intersection area into multiple areas;

[0038] When dividing the intersection area, each area does not contain intersections, and the intersections are located at the junctions of adjacent areas.

[0039] like Figure 3 As shown, in this embodiment, the intersection of the lanes is divided into six areas, that is, the area at the intersection of the lanes is divided into different areas according to the principle of not including bifurcation points, and the complex lanes at the intersection of the lanes are simplified into a single simple space. Each area does not contain intersections to facilitate subsequent management.

[0040] S3. Dig equilateral triangle grooves on both sides of the tunnel;

[0041] Among them, the side length of the equilateral triangle is 0.3-0.7 times the width of the roadway, and the groove and the roadway space form a truncated cone cavity structure. Dig grooves on both sides of the roadway in each area, and the cross-section of the groove is an irregular equilateral triangle, so that the side length of the equilateral triangle is 0.3-0.7 times the width of the roadway. It has been verified on site that this ratio is convenient for construction, stable in structure, and has better effect. The groove and the original space of the roadway form a truncated cone cavity structure. The equilateral triangle-shaped truncated cone cavity can effectively increase the bonding force between the roadway surrounding rock and the grouting filling in the roadway, ensuring the stability of the roadway; on the other hand, it makes construction more convenient.

[0042] S4. Grouting the surrounding rock of the tunnel and constructing grouting anchor reinforcement;

[0043] The tunnel surrounding rock grouting is specifically to carry out grouting reinforcement in the plastic failure zone of the tunnel surrounding rock, and the grouting anchor cable is used to fill the cracks and pores in the elastic zone of the tunnel surrounding rock. To reinforce the tunnel surrounding rock, the grouting holes are used to carry out grouting reinforcement in the plastic failure zone of the tunnel surrounding rock, so as to enhance the strength and integrity of the tunnel surrounding rock and improve the bonding force; at the same time, the grouting anchor cable is arranged to fill the cracks and pores in the elastic core zone of the tunnel surrounding rock to form an anchoring section, and the pull rod is anchored in the rock and soil layer to give full play to the anchoring effect of the anchor cable and enhance the tensile performance of the tunnel surrounding rock; in this way, the preliminary treatment of the tunnel surrounding rock is achieved and the stability of the tunnel surrounding rock is ensured.

[0044] S5. Set up a ventilation pipe in the middle of the tunnel, set up a three-way valve at the intersection of the tunnels, and wrap a protective layer outside the ventilation pipe;

[0045] A valve is arranged on the ventilation pipe, and the ventilation pipe is a hollow steel pipe. The protective layer includes a first PE film layer, a steel wire mesh layer and a second PE film layer, and the first PE film layer, the steel wire mesh layer and the second PE film layer are arranged in sequence from the inside to the outside.

[0046] In this embodiment, a ventilation pipe is set up in the center of each tunnel. The pipe is a hollow steel pipe. At the same time, in areas 1, 4, and 6 where the tunnels intersect, pipes in three directions are connected by three-way valves; and valves are arranged on the side of areas 1, 4, and 6 away from the intersection of the tunnels to control the flow of gas.

[0047] S6. Fill and seal according to the area division.

[0048] The filling and sealing process includes: arranging steel mesh, setting slurry retaining plates, filling and grouting concrete, and removing the slurry retaining plates after the slurry solidifies. The filling and sealing is grouting and filling in sequence according to the multiple areas divided in step S2.

[0049] First, a steel mesh is arranged in area 1 to enhance the tensile and compressive properties of the filling body in the area.

[0050] Then, slurry retaining plates are arranged on both sides of area 1, and grouting ports are reserved; valves are installed on the grouting ports, and the opening and closing of the grouting ports can be controlled by the valves.

[0051] Then, grouting is carried out into area 1 through the grouting port, and concrete slurry is injected therein. Grouting can be stopped only after the grouting pressure is stably increased to the set value to ensure that the slurry completely fills the filling area.

[0052] The slurry retaining plate can be removed only after the slurry in the grouting area has solidified and stabilized.

[0053] Then, the steps of "arranging steel mesh - arranging grouting plate - injecting concrete slurry" are carried out in each area in turn as in area 1 above. If one end of the area currently being filled is already filled, there is no need to arrange a grouting plate at this end, and grouting can be carried out from the other end to ensure the continuity of the filling body.

[0054] Finally, after all areas are filled and remain stable, a complete filling body can be formed, so that the intersection of the tunnels has both stability and sealing requirements. Through regional grouting reinforcement and the use of connected pipes to connect different tunnels, the bearing capacity of the surrounding rock at the intersection of the tunnels is effectively improved, the pressure on the surrounding rock at the intersection of the tunnels is reduced, and the stability of the surrounding rock at the intersection of the tunnels is increased; at the same time, this method ensures smooth gas flow, facilitates the control of gas flow, and has stronger airtightness and is more economical.

[0055] In addition, the arrangement method of the tunnel intersection points for compressed gas energy storage in abandoned shaft and tunnel space can also be applied to tunnel intersection types such as sharp intersection points or bull nose intersection points.

[0056] This method uses regional grouting reinforcement and uses connecting pipes to connect multiple tunnels. At the intersection of tunnels in abandoned shafts and tunnels, the surrounding rock is first treated initially, and then regional grouting reinforcement is performed. On the one hand, it can significantly reduce the difficulty of treatment, and on the other hand, it can effectively improve the bearing capacity of the tunnel and increase the stability of the surrounding rock at the intersection of the tunnels. In the preliminary treatment of the surrounding rock at the intersection of tunnels in abandoned shafts and tunnels, shallow grouting and deep grouting anchor cable treatment methods are used to ensure the stability of the tunnel surrounding rock. At the intersection of tunnels in abandoned shafts and tunnels, connecting pipes are used to connect multiple tunnels. On the one hand, it can ensure smooth gas flow, and installing valves makes it easier to control the gas flow direction; on the other hand, the ventilation pipe becomes the main part that carries the gas pressure, reducing the pressure borne by the surrounding rock at the intersection of the tunnels, thereby effectively avoiding the damage of the surrounding rock.

[0057] This method is universal in terms of the management method for tunnel intersections in the utilization of compressed gas energy storage in abandoned shaft and tunnel spaces, and is also applicable to other types of tunnel intersections.

[0058] Of course, the above description is not a limitation of the present invention, and the present invention is not limited to the above examples. Changes, modifications, additions or substitutions made by technicians in this technical field within the essential scope of the present invention should also fall within the protection scope of the present invention.

Claims

1. A method for arranging the intersection of abandoned shaft and lane spaces for compressed gas energy storage, characterized in that the steps include: S1. Use geophysical detection methods to conduct preliminary detection of the tunnel intersections, determine the stress and deformation state of the tunnel surrounding rock at the tunnel intersections, and determine the elastic-plastic zone range of the tunnel surrounding rock; S2. Divide the roadway intersection area into multiple areas; S3. Dig equilateral triangle grooves on both sides of the tunnel; S4. Grouting the surrounding rock of the tunnel and constructing grouting anchor reinforcement; S5. Set up a ventilation pipe in the middle of the tunnel, set up a three-way valve at the intersection of the tunnels, and wrap a protective layer outside the ventilation pipe; S6. Fill and seal according to the area division; The geophysical exploration methods include direct current resistivity method, electromagnetic exploration method and gravity exploration method; The side length of the equilateral triangle is 0.3-0.7 times the width of the lane, and the groove and the lane space form a truncated cone cavity structure; The tunnel surrounding rock grouting specifically involves grouting reinforcement of the plastic failure zone of the tunnel surrounding rock, and the grouting anchor fills the cracks and pores in the elastic zone of the tunnel surrounding rock.

2. The method for arranging the intersection of abandoned shaft and lane spaces for compressed gas energy storage according to claim 1 is characterized in that: The protective layer comprises a first PE film layer, a steel mesh layer and a second PE film layer, and the first PE film layer, the steel mesh layer and the second PE film layer are arranged in sequence from the inside to the outside.

3. The method for arranging the intersection of abandoned shaft and lane spaces for compressed gas energy storage according to claim 1 is characterized in that: The filling and sealing process includes: arranging steel mesh, setting slurry retaining plates, filling and grouting with concrete, and removing the slurry retaining plates after the slurry solidifies.

4. The method for arranging the intersection of abandoned shaft and lane spaces for compressed gas energy storage according to claim 1 is characterized in that: The filling and sealing is performed by grouting and filling in sequence according to the multiple areas divided in step S2.

5. The method for arranging the intersection of abandoned shaft and lane spaces for compressed gas energy storage according to claim 1 is characterized in that: When dividing the intersection area, each area does not contain intersections, and the intersections are located at the junctions of adjacent areas.

6. The method for arranging the intersection of abandoned shaft and lane spaces for compressed gas energy storage according to claim 1 is characterized in that: A valve is arranged on the ventilation pipe, and the ventilation pipe is a hollow steel pipe.

7. The method for arranging the intersection of abandoned shaft and lane spaces for compressed gas energy storage according to claim 1 is characterized in that: The method for arranging the intersection points of abandoned shaft and lane spaces for compressed gas energy storage is applied to the intersection points through the tip or the intersection points with the bull nose.

Images