A tunnel surrounding rock harmful gas advanced sectional detection device and method

Abstract

The application provides a tunnel surrounding rock harmful gas advanced sectional detection device and method, which comprises a gas outlet pipe, a flexible sealing assembly and a detection assembly. The gas outlet pipe is provided with a flexible sealing assembly at each end. The detection assembly is arranged on the gas outlet pipe. The gas outlet pipe is provided with a gas outlet hole. The gas outlet pipe is communicated with a negative pressure pump. The detection assembly is used for detecting harmful gas. A pressure sensor is arranged in the detection assembly and used for detecting whether gas seeps from the internal joint fissure of surrounding rock in the sealing area of the flexible sealing assembly. The gas in the sealing area of the tunnel drilling hole is extracted by the way of actively inputting negative pressure. The gas in the sealing area rapidly migrates and diffuses. Finally, the gas in the sealing area is detected by the detection assembly, so that the detection efficiency and accuracy are ensured. The way of negative pressure gas suction can also detect whether the surrounding rock has gas seepage, so that the safety of the tunnel is ensured.

Description

Technical Field

[0001] This invention relates to the field of hazardous gas detection in tunnel surrounding rock, specifically to an advanced segmented detection device and method for hazardous gases in tunnel surrounding rock. Background Technology

[0002] Hazardous gas hazards are the third largest disaster during tunnel construction, after mudslides, water inrushes, and rock bursts. Southwest my country is characterized by its undulating terrain, complex geological structure, frequent earthquakes, and significant hazard effects. Typical hazardous gas tunnel projects in Southwest China include the Longxi Tunnel, Zhegushan Tunnel, Yuelongmen Tunnel, Huangjialiang Tunnel, and Hongdoushan Tunnel. The types of hazardous gases seeping from the surrounding rock mainly include methane, carbon monoxide, hydrogen sulfide, and nitrogen oxides. The seepage of hazardous gases from the surrounding rock is unpredictable and seriously endangers the health and lives of construction workers, posing a significant challenge to tunnel construction. Therefore, advanced detection of hazardous gases in the surrounding rock is crucial for guiding the safe construction of tunnels with hazardous gas hazards.

[0003] The prior art, disclosed in CN114294063B, describes a rapid segmented detection device and method for harmful gases in tunnel surrounding rock. This prior art involves segmenting the tunnel using flexible sealing components, followed by detection using a gas detection component positioned between two flexible seals. This detection method is time-consuming because the gas in the sealed section within the borehole is in a relatively stable state. Stable gas does not actively migrate to the gas detection component for detection; it only comes into contact with the component when the gas is in a slow-moving state, resulting in poor detection timeliness. Furthermore, while this prior art discloses segmented detection, it does not explore how to expel the harmful gases, thus failing to provide a theoretical basis for allowing construction workers to directly perform construction operations inside the tunnel. Summary of the Invention

[0004] The purpose of this invention is to provide an advanced segmented detection device and method for harmful gases in tunnel surrounding rock, so as to solve the problems mentioned in the background art.

[0005] To achieve the above objectives, the present invention provides the following technical solution:

[0006] A tunnel surrounding rock hazardous gas advanced segmented detection device includes an outlet pipe, a flexible sealing assembly, and a detection assembly. A flexible sealing assembly is provided at each end of the outlet pipe, and the detection assembly is mounted on the outlet pipe.

[0007] The vent pipe is provided with an vent hole and is connected to a negative pressure pump. The detection component is used to detect harmful gases, and the detection component is equipped with a pressure sensor to detect whether there is gas seeping out from the joints and fissures inside the surrounding rock in the sealing area of ​​the flexible sealing component.

[0008] Preferably, the detection component is mounted on the exhaust pipe and forms a sliding pair in the direction of the central axis of the exhaust pipe.

[0009] Preferably, the detection device further includes a linear drive mechanism, wherein the actuating component of the linear drive mechanism is connected to the detection component.

[0010] Preferably, the linear drive mechanism includes a turbine, a drive rod, and a sliding frame. The turbine is rotatably installed inside the exhaust pipe and located near the negative pressure pump. The drive rod is rotatably installed inside the exhaust pipe and connected to the turbine. The outer surface of the drive rod is provided with a cross-shaped double helix guide groove. The sliding frame is fitted into a horizontal guide groove on the exhaust pipe, and the guide rod on the sliding frame cooperates with the cross-shaped double helix guide groove on the drive rod.

[0011] Preferably, the detection component includes a support frame and a gas sensor, the support frame being mounted on the gas outlet pipe and the gas sensor being mounted on the support frame.

[0012] Preferably, the flexible sealing assembly includes a support plate, an airbag, and an air pump. The support plate is sleeved on the end of the air outlet pipe, while the airbag is disposed on the outer circumference of the support plate, wherein the airbag is connected to the air pump.

[0013] Preferably, one end of the air outlet pipe is connected to the connecting pipe, and the negative pressure pump is connected to the connecting pipe.

[0014] A detection method for a tunnel surrounding rock hazardous gas advanced segmented detection device as described above includes the following steps:

[0015] S1, insert the vent pipe into the advanced borehole at the tunnel face;

[0016] S2 achieves the sealing effect by flexibly contacting the inner wall of the tunnel borehole with the flexible sealing component;

[0017] S3, the negative pressure pump introduces negative pressure into the vent pipe, so the gas in the blocked area is discharged along the vent pipe. At this time, the gas in the borehole blocked area is in a continuous flow state, and the pressure sensor can detect whether there is gas seeping into the advance borehole along the joints and fissures inside the surrounding rock.

[0018] S4, the detection component detects the gas in a continuously flowing state to determine whether there are gases harmful to the human body;

[0019] S5, move the air outlet pipe so that the detection component can detect different locations inside the advanced borehole.

[0020] Preferably, in step S3, the pressure sensor detects whether gas is seeping out by means of a negative pressure pump drawing air from the tunnel borehole sealing area. If no harmful gas seeps out of the surrounding rock, the pressure inside the sealing area will continue to decrease, and the pressure sensor can directly detect this. Conversely, the pressure sensor reading will not fluctuate significantly, and the pressure sensor reading can be used to directly and intuitively determine whether gas is seeping out along the joints and fissures inside the surrounding rock.

[0021] Compared with the prior art, the beneficial effects of the present invention are:

[0022] This invention extracts gas from the tunnel borehole sealing area by actively introducing negative pressure. The gas in the sealing area then rapidly migrates and diffuses. Ultimately, all the gas in the sealing area is detected by a detection component, ensuring the efficiency and accuracy of the detection. Furthermore, the negative pressure suction method can also detect whether there is gas seepage from the surrounding rock, ensuring the safety of the tunnel interior. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the overall structure of the present invention;

[0024] Figure 2 This is a three-dimensional schematic diagram of the air outlet pipe and its assembly components in this invention;

[0025] Figure 3 for Figure 2 Cross-sectional view under full sectioning;

[0026] Figure 4 This is a three-dimensional schematic diagram of the linear drive mechanism in this invention;

[0027] Figure 5 This is a three-dimensional schematic diagram of the detection component in this invention.

[0028] In the diagram: 1. Exhaust pipe, 2. Flexible sealing assembly, 3. Detection assembly, 4. Pressure sensor, 5. Linear drive mechanism, 6. Negative pressure pump, 11. Exhaust port, 12. Connecting pipe, 21. Support plate, 22. Airbag, 23. Air pump, 31. Support frame, 32. Gas sensor, 51. Turbine, 52. Drive rod, 53. Sliding frame. Detailed Implementation

[0029] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0030] Example:

[0031] Please see Figures 1 to 5 The present invention provides a technical solution:

[0032] A segmented advanced detection device for harmful gases in tunnel surrounding rock includes an outlet pipe, a flexible sealing assembly, and a detection assembly, wherein:

[0033] A flexible sealing component 2 is installed at each end of the vent pipe 1. The flexible sealing component 2 can seal the pre-drilled borehole in the tunnel, thus preventing harmful gases from seeping into the tunnel environment along the borehole. A detection component 3 is installed on the vent pipe 1, located in the middle section of the vent pipe 1. The vent pipe 1 has an vent hole 11 and is connected to a negative pressure pump 6. The negative pressure pump 6 and the vent pipe 1 can actively draw out the gas in the borehole sealing area of ​​the tunnel. The detection component 3 is used to detect harmful gases, and a pressure sensor 4 is installed inside the detection component 3 to detect whether there is gas seepage along the joints and fissures inside the surrounding rock in the sealing area of ​​the flexible sealing component 2. Since harmful gases may exist in the surrounding rock of the tunnel, the pressure sensor 4 detects the change in air pressure in the sealing area to determine whether gas seepage exists, which can effectively prevent construction workers from directly entering the tunnel where there is a risk of harmful gas seepage.

[0034] As a preferred embodiment, the negative pressure pump 6 is connected to an external gas storage tank to prevent the negative pressure pump 6 from directly discharging the extracted harmful gases into the tunnel environment.

[0035] In a preferred embodiment, the detection component 3 is mounted on the exhaust pipe 1 and forms a sliding pair along the central axis of the exhaust pipe 1. Therefore, the position of the detection component 3 can be changed accordingly to adapt to different detection environments.

[0036] In a preferred embodiment, the detection device further includes a linear drive mechanism 5, wherein the actuating component of the linear drive mechanism 5 is connected to the detection component 3. The linear drive mechanism 5 drives the detection component 3 to reciprocate longitudinally, thereby enabling the detection component 3 to quickly contact the gas being detected when detecting harmful gases, thus improving detection efficiency.

[0037] In a preferred embodiment, the linear drive mechanism 5 includes a turbine 51, a drive rod 52, and a sliding frame 53. The turbine 51 is rotatably mounted inside the air outlet pipe 1 and located near the negative pressure pump 6. The drive rod 52 is rotatably mounted inside the air outlet pipe 1 and connected to the turbine 51. The outer surface of the drive rod 52 is provided with a cross-shaped double-helix guide groove. The sliding frame 53 is fitted into a transverse guide groove on the air pipe 1. The guide rod on the sliding frame 53 engages with the cross-shaped double-helix guide groove on the drive rod 52. The transverse guide groove is parallel to the central axis of the air outlet pipe 1. When the drive rod 52 rotates, the cross-shaped double-helix guide groove drives the sliding frame 53 to reciprocate. The detection component 3 is connected to the sliding frame 53, which serves as the actuating component. When the negative pressure pump 6 extracts harmful gas from the tunnel borehole sealing area, it drives the turbine 51 to rotate. The turbine 51 then drives the drive rod 52 to rotate synchronously. The rotating drive rod 52 drives the sliding frame 53 to move back and forth, so that the detection component 3 can move back and forth along the axial direction of the gas outlet pipe 1. Thus, the detection component 3 actively contacts the harmful gas, ensuring the efficiency of detection.

[0038] In a preferred embodiment, the above embodiment uses the negative pressure pump 6 to draw air and drive the turbine 51 to rotate, thereby providing power for the sliding frame 53 to move the detection component 3 horizontally. In order to ensure that the detection component 3 reaches the preset motion state, the sliding frame 53 and the horizontal guide groove are in sliding contact, the detection component 3 and the air outlet pipe 1 are in sliding contact, and the negative pressure pump 6 is a high-pressure air pump.

[0039] As a preferred embodiment, the linear drive mechanism 5 is not limited to the turbine 51, drive rod 52 and sliding frame 53. It can also be composed of slider, lead screw and motor. Of course, it can also be a linear electric cylinder, linear air cylinder and other components. Ultimately, it can drive the detection component 3 to reciprocate and translate without interfering with the motion of other components. Those skilled in the art can adaptively select the specific drive structure according to actual needs.

[0040] In a preferred embodiment, the detection component 3 includes a support frame 31 and a gas sensor 32. The support frame 31 is mounted on the gas outlet pipe 1, and the gas sensor 32 is mounted on the support frame 31.

[0041] In a preferred embodiment, the gas sensor 32 is used to detect the concentration of gases such as H2S, SO2, CH4, NO2, CO, CO2, etc., or to measure a single harmful gas. That is, the support frame 31 is equipped with one or more gas sensors 32.

[0042] In a preferred embodiment, the flexible sealing assembly 2 includes a support plate 21, an airbag 22, and an air pump 23. The support plate 21 is sleeved on the end of the air outlet pipe 1, while the airbag 22 is disposed on the outer circumference of the support plate 21, wherein the airbag 22 is connected to the air pump 23. Gas is then introduced into the airbag 22 by the air pump 23 to cause it to expand, thus making the airbag 22 come into close contact with the inner wall of the tunnel borehole to achieve a sealing effect.

[0043] In a preferred embodiment, one end of the vent pipe 1 is connected to the connecting pipe 12, and the negative pressure pump 6 is also connected to the connecting pipe 12. Therefore, when detecting harmful gases at different depths within the borehole, the number of connecting pipes 12 is increased, allowing the vent pipe 1 to reach a preset position. In other words, the position of the vent pipe 1 within the borehole is changed by connecting multiple connecting pipes 12.

[0044] A detection method for a segmented advanced detection device for harmful gases in tunnel surrounding rock includes the following steps:

[0045] S1, insert the vent pipe 1 into the advanced borehole at the tunnel face;

[0046] S2, the flexible sealing component 2 makes flexible contact with the inner wall of the tunnel borehole to achieve the sealing effect;

[0047] S3, negative pressure is introduced into the vent pipe 1 by the negative pressure pump 6, and the gas in the sealing area is discharged along the vent pipe 1. At this time, the gas in the borehole sealing area is in a continuous flow state, and the pressure sensor 4 can detect whether gas seeps into the advance borehole along the joints and fissures inside the surrounding rock. Specifically, the pressure sensor 4 detects whether gas seeps out by drawing air from the tunnel borehole sealing area by the negative pressure pump 6. If no harmful gas seeps out of the surrounding rock, the pressure inside the sealing area will continue to decrease, and the pressure sensor 4 can directly determine whether gas seeps out along the joints and fissures inside the surrounding rock.

[0048] S4, the detection component 3 detects the gas in a continuously flowing state to determine whether there is any gas harmful to the human body;

[0049] S5, move the air outlet pipe 1 so that the detection component 3 can detect different locations inside the advanced borehole.

[0050] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A tunnel surrounding rock hazardous gas advanced segmented detection device, comprising an outlet pipe (1), a flexible sealing component (2), and a detection component (3), wherein a flexible sealing component (2) is provided at each end of the outlet pipe (1), and the detection component (3) is disposed on the outlet pipe (1), characterized in that: The vent pipe (1) is provided with a vent hole (11), and the vent pipe (1) is connected to the negative pressure pump (6). The detection component (3) is used to detect harmful gases, and the detection component (3) is provided with a pressure sensor (4) to detect whether there is gas seeping out from the joints and fissures inside the surrounding rock in the sealing area of ​​the flexible sealing component (2). The detection component (3) is installed on the exhaust pipe (1) and forms a sliding pair in the direction of the central axis of the exhaust pipe (1); The detection device further includes a linear drive mechanism (5), wherein the actuating component of the linear drive mechanism (5) is connected to the detection assembly (3); The linear drive mechanism (5) includes a turbine (51), a drive rod (52), and a sliding frame (53). The turbine (51) is rotatably installed in the exhaust pipe (1) and located near the negative pressure pump (6). The drive rod (52) is rotatably installed in the exhaust pipe (1) and connected to the turbine (51). The outer surface of the drive rod (52) is provided with a cross-shaped double helix guide groove. The sliding frame (53) is fitted in a horizontal guide groove on the exhaust pipe (1). The guide rod on the sliding frame (53) is fitted with the cross-shaped double helix guide groove on the drive rod (52). The detection component (3) includes a support frame (31) and a gas sensor (32). The support frame (31) is mounted on the gas outlet pipe (1), and the gas sensor (32) is mounted on the support frame (31).

2. The tunnel surrounding rock hazardous gas advanced segmented detection device according to claim 1, characterized in that: The flexible sealing component (2) includes a support plate (21), an airbag (22) and an air pump (23). The support plate (21) is sleeved on the end of the air outlet pipe (1), and the airbag (22) is disposed on the outer circular surface of the support plate (21). The airbag (22) is connected to the air pump (23).

3. The tunnel surrounding rock hazardous gas advanced segmented detection device according to claim 1, characterized in that: One end of the air outlet pipe (1) is connected to the connecting pipe (12), and the negative pressure pump (6) is connected to the connecting pipe (12).

4. A detection method for a tunnel surrounding rock hazardous gas advanced segmented detection device according to claim 1, characterized in that, Includes the following steps: S1, insert the vent pipe (1) into the advanced borehole at the tunnel face; S2, the flexible sealing component (2) makes flexible contact with the inner wall of the tunnel borehole to achieve the sealing effect; S3, negative pressure pump (6) introduces negative pressure into the air outlet pipe (1), then the gas in the sealing area is discharged along the air outlet pipe (1). At this time, the gas in the borehole sealing area is in a continuous flow state, and the pressure sensor (4) can detect whether there is gas seeping into the advanced borehole along the joints and fissures inside the surrounding rock. S4, the detection component (3) detects the gas in a continuous flow state and determines whether there is a gas that is harmful to the human body; S5, move the air outlet pipe (1) so that the detection component (3) can detect different locations in the advanced borehole.

5. The detection method of the tunnel surrounding rock hazardous gas advanced segmented detection device according to claim 4, characterized in that: In the S3, the pressure sensor (4) detects whether gas is seeping out. Specifically, the negative pressure pump (6) draws air from the tunnel borehole sealing area. If no harmful gas seeps out of the surrounding rock, the pressure inside the sealing area will continue to decrease, and the pressure sensor (4) can directly obtain the result. Otherwise, the reading of the pressure sensor (4) will not fluctuate significantly. Thus, the pressure sensor (4) can directly and intuitively determine whether gas seeps out along the joints and fissures inside the surrounding rock by directly using the data measured by the pressure sensor (4).

Images