Method for excavating frozen soil of connecting channel by using Airdox blasting system

Abstract

The invention discloses a method for excavating frozen soil of a connecting channel by using an Ai rdox blasting system. The method comprises the following steps: step (1), arranging blasting holes in an excavation tunnel face of the frozen soil of the connecting channel; (2) a blasting cartridge is installed in the blasting hole, and the air inlet end of the blasting cartridge is connected with air supply equipment of an Ai rdox blasting system; (3) the gas supply equipment is started for blasting the blasting cartridges, and only one blasting cartridge is blasted each time; and (4) after all the blast holes are blasted, the excavation condition is checked, and secondary crushing is conducted manually through an air pick. The technical problems that an existing communication channel frozen soil excavation method is poor in safety and low in construction efficiency can be solved.

Description

Technical Field

[0001] The present invention relates to the technical field of frozen soil excavation of communication channels, and more specifically to a method for excavating frozen soil of communication channels by using an Airdox blasting system. Background Art

[0002] my country's subway construction is in full swing, and the total mileage of subways is increasing. Correspondingly, the number of subway access channel construction projects has also increased. Subway access channels basically use artificial freezing methods to stop water and load to form frozen walls to reinforce the strata. Due to the large differences in the properties of frozen soil, thawed soil and hard rock, it is difficult to excavate frozen soil. At present, manual pneumatic picks are generally used to excavate frozen soil in access channels, and the excavation efficiency is extremely low.

[0003] CN116817689A discloses a method for excavating subway communication channels using a carbon dioxide fracturing device, which uses a carbon dioxide fracturing device to break up the frozen soil in the communication channel, causing little vibration damage to the frozen wall, low noise, no flying rocks during blasting, and basically no environmental pollution. However, this method requires a large number of carbon dioxide fracturing devices, and there are still certain safety hazards during the filling and transportation of the carbon dioxide fracturing devices, and it is necessary to wait for a period of time for ventilation after blasting before continuing the operation.

[0004] CN116677391A discloses a static crushing agent excavation method for subway communication channels, which uses static crushing agents to crush frozen soil in communication channels. This method is vibration-free, noise-free, and does not damage frozen walls. However, when this method is used to crush frozen soil, it is necessary to expand the static crushing agents in the middle and lower crushing holes, crush the frozen soil in the center, and then load the auxiliary crushing holes. This will result in a long cracking time for each crushing. In addition, the hole spacing of the crushing holes is small, and a large number of crushing holes need to be constructed, so the construction efficiency is low.

[0005] Therefore, it is necessary to find new methods for excavating frozen soil in connecting channels to improve the safety and efficiency of frozen soil excavation construction in connecting channels. Summary of the invention

[0006] To this end, the technical problem to be solved by the present invention is to provide a method for excavating frozen soil in a communication channel using an Airdox blasting system, so as to solve the technical problems of poor safety and low construction efficiency of the existing methods for excavating frozen soil in communication channels.

[0007] In order to solve the above technical problems, the present invention provides the following technical solutions:

[0008] A method for excavating frozen soil in a communication channel using an Airdox blasting system, mainly using gas jet and high-pressure gas quasi-static expansion action, supplemented by artificial secondary crushing, to excavate a subway communication channel after the frozen wall is formed, specifically comprising the following steps:

[0009] Step (1), arranging blasting holes on the excavation face of frozen soil in the communication channel;

[0010] Step (2), inserting a blasting tube into the blasting hole, and connecting the high-pressure gas inlet end of the blasting tube to the gas supply equipment of the Airdox blasting system;

[0011] Step (3), starting the gas supply device to blast the blasting tubes, blasting only one blasting tube at a time; after starting the gas supply device, when the gas pressure reaches the pressure required for blasting, the shear plate in the blasting tube is broken, and the high-pressure air is suddenly released, so that a large number of cracks are generated in the frozen soil around the blasting tube;

[0012] Step (4), after all the blasting tubes are blasted, check the excavation situation and then perform secondary crushing manually using a pneumatic pick.

[0013] Airdox blasting is a physical blasting technology that uses mechanical equipment or physical changes to generate high-pressure gas. An Airdox blasting tube is installed in the medium, and the high-pressure gas in the blasting tube is instantly released through a manual or automatic operating mechanism, which impacts the surrounding medium and breaks it by expansion. The present invention improves the Airdox blasting system using the Airdox blasting technology and uses it for excavating frozen soil in the communication channel, which can effectively solve the technical problems of poor safety and low construction efficiency in the background technology.

[0014] In the above method of excavating frozen soil in a communication channel using an Airdox blasting system, in step (1), the blasting holes include a central blasting barrel hole, peripheral blasting barrel holes, auxiliary empty holes and peripheral empty holes; the central blasting barrel hole is located at the center of the excavation face, and the peripheral blasting barrel holes are distributed around the central blasting barrel hole; the auxiliary empty holes are located in the area between two adjacent peripheral blasting barrel holes; and the peripheral empty holes are distributed along the area adjacent to the excavation contour line.

[0015] In the above-mentioned method of excavating frozen soil of a communication channel using the Airdox blasting system, there are 4 peripheral blasting barrel holes; the 4 peripheral blasting barrel holes are connected to form a quadrilateral, and at least one group of two peripheral blasting barrel holes located at opposite corners of the quadrilateral are equidistant from the central blasting barrel hole; there are 4 auxiliary empty holes, and the 4 auxiliary empty holes are connected to form a rectangle; there are 22 peripheral empty holes, and the 22 peripheral empty holes are evenly spaced along the area adjacent to the excavation contour line.

[0016] In the above method of excavating frozen soil of the communication channel using the Airdox blasting system, the shortest distances from all the surrounding blasting tube holes and all the auxiliary empty holes to the excavation contour line are equal.

[0017] In the above method of excavating frozen soil in the communication channel using the Airdox blasting system, the distance from the peripheral empty holes to the excavation contour line is greater than or equal to 25 cm. The peripheral empty holes are arranged in a circle along the excavation contour line, and the peripheral empty hole circle is reserved at least 25 cm from the excavation contour line as a protective layer to avoid disturbance and damage to the frozen wall during the frozen soil blasting excavation process. The distance between two adjacent peripheral empty holes is 500-600 mm; the distance between two adjacent peripheral blasting barrel holes is 1200-1500 mm; the distance from the peripheral blasting barrel hole to the central blasting barrel hole is 800-1200 mm; the distance from the peripheral blasting barrel hole to the excavation contour line is 800-1200 mm; the distance from the auxiliary empty hole to the excavation contour line is 900-1100 mm.

[0018] In the above method of excavating frozen soil in a communication channel using the Airdox blasting system, in step (1), the diameter of the blasting hole is 72 mm and the depth is 1.1 m; the diameter of the blasting tube is 60 mm and the length is 1050 mm.

[0019] The design of the above-mentioned blasting parameters such as the spacing and depth of blasting holes, and the size of blasting tubes can give full play to the crushing effect of the blasting tubes on frozen soil, thereby achieving the purpose of achieving a more ideal blasting effect while using fewer blasting tubes.

[0020] In the above method of excavating frozen soil in a communication channel using the Airdox blasting system, in step (2), the blasting tube is loaded into the central blasting tube hole and the peripheral blasting tube hole; one blasting tube is loaded into each of the central blasting tube hole and the peripheral blasting tube hole; and the release end of the blasting tube is placed at the bottom of the blasting hole.

[0021] In the above method of excavating frozen soil in the communication channel using the Airdox blasting system, in step (3), the blasting order of the blasting tubes is: first blast the blasting tubes in the central blasting tube hole, and then blast the blasting tubes in the peripheral blasting tube holes; the blasting order of the blasting tubes in the peripheral blasting tube holes is: blasting in the order of "up-left-down-right" or "up-right-down-left". This blasting order can first produce a large cavity in the center of the face, forming a new free surface, reducing the blasting difficulty of the peripheral blasting holes, and significantly improving the blasting effect of the peripheral blasting holes; in addition, during the blasting process, the design of the auxiliary holes provides free surfaces for both the central blasting tube hole and the peripheral blasting tube hole, and provides space for the expansion and crushing of frozen soil, thereby effectively improving the energy utilization rate and blasting efficiency of the blasting tube, and achieving an ideal blasting effect.

[0022] When using the Airdox blasting system to blast and excavate the frozen soil of the connecting channel, the arrangement of the blasting holes and the blasting parameters are the key to whether the frozen soil excavation can achieve an ideal blasting effect. The present invention enables the Airdox blasting system to achieve a relatively ideal blasting effect by scientifically and reasonably designing the blasting parameters such as the distribution, spacing and detonation method of the blasting holes and empty holes. When using fewer blasting tubes, the frozen soil of the connecting channel can be fully broken, and the disturbance to the frozen wall around the connecting channel is less, providing favorable conditions for the subsequent construction safety and efficiency.

[0023] In the above method of excavating frozen soil in a communication channel using an Airdox blasting system, in step (2), the blasting tube adopts a single-point blasting tube produced by China Coal Technology and Engineering Group Shenyang Research Institute Co., Ltd., or may be other blasting tubes that can use high-pressure air to achieve blasting; the air supply equipment includes an air compressor, a booster pump and a high-pressure delivery hose; the air compressor is an Ingersoll Rand Infinity series 5.5-11KW micro-oil screw air compressor; the booster pump is Yasno YSN-1005; the high-pressure delivery hose is made of Q / SXS J02.723 high-pressure steel wire winding hose; in step (3), the high-pressure gas is air, and the release pressure of the high-pressure gas is 10 to 85MPa. High-pressure gas is filled into the blasting tube through the gas supply equipment. When the pressure in the blasting tube reaches the pressure required for blasting, the shear plates in the blasting tube will be sheared and damaged under the action of the gas pressure, so that the high-pressure gas is quickly released along the exhaust holes of the blasting tube. The high-pressure gas impacts the surrounding frozen soil to form cracks and pushes outward along the crack surface, thereby breaking the frozen soil.

[0024] The above method of excavating frozen soil in the communication channel using the Airdox blasting system also includes step (5), after the excavation is completed, constructing a waterproof layer and performing reinforced concrete structure construction.

[0025] The technical solution of the present invention achieves the following beneficial technical effects:

[0026] 1. The present invention uses the Airdox blasting system to excavate the subway connecting channel, and generates high-pressure gas by mechanical means. Under the impact of the high-pressure gas jet and the quasi-static expansion of the high-pressure gas, the frozen soil produces a large number of crisscrossing macro cracks and micro cracks to form a crack network, which is easier to break with a pneumatic pick and easier to operate; compared with pure manual pneumatic pick excavation, the present invention can improve excavation efficiency, shorten excavation period, and reduce excavation costs. The present invention uses the Airdox blasting system to excavate the frozen soil of the connecting channel. Compared with the excavation method of the carbon dioxide fracturing device in the background technology, it does not require dangerous high-pressure liquid carbon dioxide, and has high safety during production, transportation, and storage; compared with the excavation method of the static crushing agent in the background technology, the crushing hole spacing is large, and there is no need to lay too many drill holes, and the construction efficiency is high.

[0027] 2. The present invention mainly uses gas jet and high-pressure gas quasi-static expansion, supplemented by artificial secondary crushing, to excavate the subway communication channel after the frozen wall is formed. Since the high-pressure gas release pressure of the Airdox blasting system in the present invention can be adjusted according to the strength of the frozen soil in the excavation face, the controllability is good. Therefore, the Airdox blasting system has little vibration damage to the frozen wall and no environmental pollution problem, and is very suitable for excavating frozen soil in subway communication channels. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 A schematic diagram of the excavation face structure of frozen soil to be excavated for a communication channel in an embodiment of the present invention;

[0029] Figure 2 Airdox blasting excavation blast hole layout diagram in the embodiment of the present invention;

[0030] Figure 3 Schematic diagram of the communication channel after excavation in the embodiment of the present invention;

[0031] Figure 4 A schematic structural diagram of a single-point blasting tube in an embodiment of the present invention.

[0032] Figures 1 to 3 The reference numerals in the figure are as follows: 1-frozen wall; 2-peripheral holes; 3-center hole for blasting tubes; 4-auxiliary holes; 5-frozen soil to be excavated in the communication channel; 6-thawed soil; 7-reinforced concrete structure; 8-communication channel; 9-peripheral holes for blasting tubes; 10-excavation contour line;

[0033] Figure 4The reference numerals in the figure are as follows: 1-connecting end; 2-blasting tube; 3-container tube; 4-connecting nut; 5-left safety outer tube; 6-right safety outer tube; 7-sliding seat valve; 8-sliding valve; 9-sliding valve head; 10-check valve seat; 11-blasting piston; 12-safety nut; 13-crossbeam; 14-baffle; 15-check valve; 16-gasket; 17 to 20 are all tight rings. DETAILED DESCRIPTION

[0034] In this embodiment, the method of excavating frozen soil in the communication channel using the Airdox blasting system includes the following steps:

[0035] Step (1), arranging blasting holes on the excavation face of frozen soil in the communication channel; the structural schematic diagram of the excavation face of frozen soil in the communication channel to be excavated in this embodiment is shown in Figure 1 ;

[0036] like Figure 2 As shown, the blasting holes include 1 central blasting tube hole 3, 4 peripheral blasting tube holes 9, 4 auxiliary empty holes 4 and 22 peripheral empty holes 2; the central blasting tube hole 3 is located at the center of the excavation face, the peripheral blasting tube holes 9 are distributed around the central blasting tube hole 3, and the 4 peripheral blasting tube holes 9 are connected to form a quadrilateral, and the distances from the two peripheral blasting tube holes 9 located on the left and right diagonals of the quadrilateral to the central blasting tube hole 3 are equal; the auxiliary empty holes 4 are located in the area between two adjacent peripheral blasting tube holes 9, and the 4 auxiliary empty holes 4 are connected to form a rectangle; the 22 peripheral empty holes 2 are evenly spaced along the area adjacent to the excavation contour line 10; the closest distances from all the peripheral blasting tube holes 9 and all the auxiliary empty holes 4 to the excavation contour line 10 are equal;

[0037] The closest distance between the peripheral empty holes 2 and the excavation contour line 10 is 25 cm; the distance between two adjacent peripheral empty holes 2 is 500 mm; the distance between two adjacent peripheral blasting tube holes 9 is 1202 mm; the distance between the peripheral blasting tube holes 9 and the central blasting tube hole 3 is 872 mm; the closest distance between the peripheral blasting tube holes 9 and the excavation contour line 10 is 1125 mm; the closest distance between the auxiliary empty holes 4 and the excavation contour line 10 is 995 mm;

[0038] In this embodiment, the diameters of the central blasting tube hole 3, the four peripheral blasting tube holes 9, the four auxiliary holes 4 and the 22 peripheral holes 2 are all 72 mm and the depths are all 1.1 m;

[0039] Step (2), load one blasting tube into each of the central blasting tube hole 3 and the four peripheral blasting tube holes 9, and connect the high-pressure gas inlet end of each blasting tube to the air supply equipment of the Airdox blasting system; the release end of the blasting tube is placed at the bottom of the central blasting tube hole 3 and the peripheral blasting tube hole 9; the diameter of the blasting tube is 60 mm and the length is 1050 mm; in this embodiment, the air supply equipment includes an air compressor, a booster pump and a high-pressure delivery hose; the air compressor is an Ingersoll Rand Infinity series 5.5-11KW micro-oil screw air compressor; the booster pump is Yasno YSN-1005; the high-pressure delivery hose is made of Q / SXS J02.723 high-pressure steel wire winding hose; the outlet end of the high-pressure delivery hose is connected to the air inlet end of the blasting tube; the blasting tube adopts a single-point blasting tube produced by China Coal Technology and Engineering Group Shenyang Research Institute Co., Ltd., and its structural schematic diagram is shown in Figure 4 (For details, see Gao Kun. Experimental Research and Application of High Energy Gas Impact Coal Body Permeability Enhancement Technology [D]. Fuxin: Liaoning University of Engineering and Technology, 2013). In some other embodiments, other blasting tubes that can use high-pressure gas to achieve frozen soil blasting can also be used;

[0040] Step (3), start the gas supply device to make the blasting tubes explode under the pressure of the high-pressure gas, and only blast one blasting tube at a time; the blasting order of the blasting tubes is: first blast the blasting tube in the central blasting tube hole 3, and then blast the blasting tube in the peripheral blasting tube hole 9; the blasting order of the blasting tubes in the peripheral blasting tube hole 9 is: blast in the order of top-left-bottom-right (see Figure 2 ), in some other embodiments, the blasting tubes in the surrounding blasting tube holes 9 can also be blasted in the order of upper right, lower left, to achieve the same blasting effect; the high-pressure gas is air; during blasting, the release pressure of the high-pressure gas is 40MPa;

[0041] Step (4), after all blasting tubes have been blasted, the excavation and crushing conditions are checked, and then a pneumatic pick is used for secondary crushing. In this embodiment, after all blasting tubes have been blasted, the frozen soil of the excavation face of the entire communication channel is crushed, and a crisscrossing crack network is generated, which greatly reduces the construction difficulty of subsequent manual crushing with a pneumatic pick and shortens the excavation period. In addition, during the entire excavation process, the frozen wall outside the communication channel is basically not damaged by vibration.

[0042] Step (5), after excavation is completed, a waterproof layer is constructed and reinforced concrete structure is constructed; the communication channel excavated in this embodiment is shown in Figure 3 .

[0043] Obviously, the above embodiments are merely examples for the purpose of clear explanation, and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived therefrom are still within the scope of protection of the claims of this patent application.

Claims

1. A method for excavating frozen soil in a communication channel using an Airdox blasting system, characterized in that: The steps include: Step (1), arranging blasting holes on the excavation face of frozen soil in the communication channel; Step (2), placing a blasting tube into the blasting hole, and connecting the air inlet end of the blasting tube to the air supply equipment of the Airdox blasting system; Step (3), starting the gas supply device to blast the blasting tubes, blasting only one blasting tube at a time; Step (4), after all the blasting holes are blasted, the excavation situation is checked, and then a secondary crushing is performed manually using a pneumatic pick.

2. The method for excavating frozen soil of a communication channel using the Airdox blasting system according to claim 1, characterized in that: In step (1), the blasting holes include a central blasting tube hole (3), peripheral blasting tube holes (9), auxiliary empty holes (4) and peripheral empty holes (2); the central blasting tube hole (3) is located at the center of the excavation face, and the peripheral blasting tube holes (9) are distributed around the central blasting tube hole (3); the auxiliary empty holes (4) are located in the area between two adjacent peripheral blasting tube holes (9); and the peripheral empty holes (2) are distributed along the area adjacent to the excavation contour line (10).

3. The method for excavating frozen soil of a communication channel using the Airdox blasting system according to claim 2, characterized in that: There are four peripheral blasting tube holes (9); the four peripheral blasting tube holes (9) are connected to form a quadrilateral, and at least one group of two peripheral blasting tube holes (9) located at opposite corners of the quadrilateral are equidistant from the central blasting tube hole (3); there are four auxiliary empty holes (4), and the four auxiliary empty holes (4) are connected to form a rectangle; there are 22 peripheral empty holes (2), and the 22 peripheral empty holes (2) are evenly spaced along the area adjacent to the excavation contour line (10).

4. The method for excavating frozen soil of a communication channel using the Airdox blasting system according to claim 3, characterized in that: The shortest distances from all the peripheral blasting tube holes (9) and all the auxiliary holes (4) to the excavation contour line (10) are equal.

5. The method for excavating frozen soil in a communication channel using an Airdox blasting system according to any one of claims 2 to 4, characterized in that: The shortest distance from the peripheral empty holes (2) to the excavation contour line (10) is greater than or equal to 25 cm; the distance between two adjacent peripheral empty holes (2) is 500 to 600 mm; the distance between two adjacent peripheral blasting tube holes (9) is 1200 to 1500 mm; the distance from the peripheral blasting tube holes (9) to the central blasting tube hole (3) is 800 to 1200 mm; the distance from the peripheral blasting tube holes (9) to the excavation contour line (10) is 800 to 1200 mm; the distance from the auxiliary empty holes (4) to the excavation contour line (10) is 900 to 1100 mm.

6. The method for excavating frozen soil of a communication channel using the Airdox blasting system according to claim 5, characterized in that: In step (1), the diameter of the blasting holes is 72 mm and the depth is 1.1 m; the diameter of the blasting tubes is 60 mm and the length is 1050 mm.

7. The method for excavating frozen soil of a communication channel using the Airdox blasting system according to claim 2, characterized in that: In step (2), the blasting tube is placed in the central blasting tube hole (3) and the peripheral blasting tube hole (9); one blasting tube is placed in each of the central blasting tube hole (3) and the peripheral blasting tube hole (9); and the release end of the blasting tube is placed in the bottom of the blasting hole.

8. The method for excavating frozen soil of a communication channel using the Airdox blasting system according to claim 2, characterized in that: In step (3), the blasting sequence of the blasting tubes is: first blasting the blasting tubes in the central blasting tube hole (3), and then blasting the blasting tubes in the peripheral blasting tube holes (9); the blasting sequence of the blasting tubes in the peripheral blasting tube holes (9) is: blasting in the order of "up-left-down-right" or "up-right-down-left".

9. The method for excavating frozen soil of a communication channel using the Airdox blasting system according to claim 1, characterized in that: In step (2), the blasting tube adopts a single-point blasting tube produced by China Coal Technology and Engineering Group Shenyang Research Institute Co., Ltd.; the air supply equipment includes an air compressor, a booster pump and a high-pressure delivery hose; the air compressor is an Ingersoll Rand Infinity series 5.5-11KW micro-oil screw air compressor; the booster pump is Yasno YSN-1005; the high-pressure delivery hose is made of Q / SXS J02.723 high-pressure steel wire winding hose; In step (3), the high-pressure gas is air, and the release pressure of the high-pressure gas is 10 to 85 MPa.

10. The method for excavating frozen soil of a communication channel using the Airdox blasting system according to claim 1, characterized in that: The method also includes step (5), after the excavation is completed, constructing a waterproof layer and carrying out reinforced concrete structure construction.

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