A construction method for preventing water penetration during drilling of mountain tunnels

Abstract

The present invention relates to the technical field of mountain tunnel construction, especially the field of drilling construction for mountain tunnels. Specifically, it relates to a construction method for preventing water penetration during drilling of mountain tunnels, which solves the problem in the prior art that when water leakage occurs in the mountain during drilling, it is necessary to retract the drill and enter again for plugging, resulting in the ejection of mountain water. It can quickly plug the sudden mountain water, ensure the construction progress, prepare several plugging strips in advance in the factory, and during the drilling construction process, when water leakage occurs in the mountain, stop the drilling work of the spiral drill rod, and fill several plugging strips into the feeding cavity; convey the plugging strips through the feeding cavity to a position close to the drill bit, and then discharge the plugging strips into the hole to plug the water leakage point of the mountain.

Description

Technical Field

[0001] The present invention relates to the technical field of mountain tunnel construction, especially the field of drilling construction of mountain tunnels, and specifically relates to a construction method for preventing water penetration during drilling of mountain tunnels. Background Art

[0002] During the construction of mountain tunnels, rock layers are often encountered. The construction method of those skilled in the art is to first drill holes in the mountain through drilling equipment, and then fill explosive charges in the holes for subsequent construction. Due to the need to fill explosive charges, there are strict requirements for the diameter and depth of the holes.

[0003] The most commonly used equipment is a drilling rig for drilling, such as a rock mountain drilling machine disclosed in the patent with the patent publication number CN112523691A. The mountain is drilled through a spiral drill rod. However, some parts of the mountain are rich in a large amount of water. When the drill hole reaches the area rich in mountain water, water will seep out of the drill hole. In order to block the mountain water, the conventional method is to retract the drill and then enter again for plugging. Then, a large amount of water will gush out, affecting subsequent construction such as explosive filling, and even requiring re-drilling. Summary of the Invention

[0004] The present invention provides a construction method for preventing water penetration during drilling of mountain tunnels, which solves the problem that when water leakage occurs during drilling in the prior art and it is necessary to retract the drill and enter again for plugging, resulting in the ejection of mountain water, and can quickly block the sudden mountain water and ensure the construction progress.

[0005] The present invention is achieved through the following technical solutions:

[0006] A construction method for preventing water penetration during drilling of mountain tunnels includes the following steps:

[0007] S10. Prepare a number of plugging strips in advance at the factory;

[0008] S20. A feeding cavity is arranged along the axial direction inside the spiral drill rod. The drilling rig enters the site, and the spiral drill rod is connected to the power head of the drilling rig;

[0009] S30. Measure and set out the drilling position on the mountain and drive in a mark;

[0010] S40. Start the drilling rig, align the drill bit of the spiral drill rod with the drilling position for drilling construction. While the spiral drill rod drills into the mountain to form a hole, the outer spiral blades on the outside of the spiral drill rod discharge the mountain debris;

[0011] S50. During the drilling construction, when water leakage of the mountain occurs, stop the drilling work of the spiral drill rod, and fill a number of plugging strips into the feeding cavity;

[0012] S60. Transport the sealing strip through the feeding chamber to a position close to the drill bit, and then discharge the sealing strip into the hole to seal the mountain water leakage point.

[0013] Further, the sealing strip is made of sulfoaluminate cement, bentonite, superabsorbent resin, polypropylene fiber, nano-silica, slow-release coagulant and plasticizer.

[0014] Further, the preparation of the sealing strip includes the following steps:

[0015] S1001. Add sulfoaluminate cement and bentonite to a mixer and mix to form a uniform base material;

[0016] S1002. Add superabsorbent resin, polypropylene fiber and nano-silica in sequence and mix to form a mixture;

[0017] S1003. Prepare an aqueous solution of the slow-release coagulant and plasticizer, and synchronously inject the aqueous solution into the mixture of S1002 through a spray system;

[0018] S1004. After stirring and mixing, form a plastic paste, and extrude the plastic paste through a screw extruder into an initial strip-shaped material;

[0019] S1005. Steam-cure the initial strip-shaped material, and then naturally dry it until the moisture content ≤ 5% to finally form a sealing strip.

[0020] Further, the shape of the sealing strip is long strip-shaped, and the length of the sealing strip is 20 - 40 cm.

[0021] Further, in step S20, the area between the drill bit and the outer spiral blade is defined as the water seepage monitoring area, and a water seepage monitoring module is provided in advance in the water seepage monitoring area;

[0022] In step S50, during the drilling construction, when mountain water leakage occurs, the water seepage detection module monitors water seepage in the hole, and then stops the drilling work of the spiral drill rod.

[0023] Further, the installation of the water seepage monitoring module includes the following steps:

[0024] S201. Process a sensor groove in the water seepage monitoring area;

[0025] S202. Install a water immersion sensor in the sensor groove;

[0026] S203. Assemble a protective cover with grid holes on the sensor groove.

[0027] Further, in step S20, a one-way discharge door is provided in advance in the water seepage monitoring area, and the one-way discharge door communicates with the feeding chamber;

[0028] In step S60, after the plugging strip enters the feeding cavity, it is conveyed to a position close to the drill bit by the conveying method of the shaftless spiral blade, and then the plugging strip is discharged into the hole through the one-way discharge door to plug the mountain water leakage point.

[0029] Further, in step S40, the rotation speed of the spiral drill pipe is controlled to 10 - 15 revolutions per minute.

[0030] The beneficial effects achieved by the present invention compared with the prior art are as follows:

[0031] 1. The present invention provides a construction method for preventing water penetration in mountain tunnels during drilling. When mountain water leakage occurs during the drilling construction process, the work of the spiral drill pipe is stopped, several plugging strips are filled into the feeding cavity, the plugging strips are conveyed to a position close to the drill bit through the feeding cavity, and then the plugging strips are discharged into the hole to plug the mountain water leakage point. This replaces the previous plugging method that requires redrilling and secondary pipe lowering, can quickly plug, has high construction efficiency, avoids the problem of water spraying during redrilling, and reduces construction costs;

[0032] 2. The plugging strip is made of sulfoaluminate cement, bentonite, superabsorbent resin, polypropylene fiber, nano - silica, slow - release coagulant and plasticizer. The polypropylene fiber enables the plugging strip to have sufficient anti - bending ability, and the superabsorbent resin can expand when encountering rainwater to form a water - stop layer, ensuring that the plugging strip can quickly plug when entering the water leakage area;

[0033] 3. An infiltration monitoring module is provided in advance in the infiltration monitoring area defined between the drill bit and the outer spiral blade. During the drilling construction process, when mountain water leakage occurs, the infiltration detection module can accurately monitor whether infiltration occurs in the hole. If infiltration occurs, the drilling work of the spiral drill pipe is stopped, avoiding a large amount of mountain water spraying and bringing difficulties to subsequent construction;

[0034] 4. Through the construction method for preventing water penetration in mountain tunnels described in the present invention, mountain water can be plugged in time, reducing the impact on the construction progress, and having high economic value and promotion value. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 is a schematic flow chart of the construction method for preventing water penetration in mountain tunnels described in the present invention;

[0036] Figure 2 is a schematic working diagram of the drill rig described in the present invention;

[0037] Figure 3 is a schematic internal view of the feeding cavity described in the present invention;

[0038] Figure 4Installation state diagram of the seepage monitoring module described in the present invention;

[0039] In the figure: 1, feeding chamber; 2, power head; 3, outer spiral blade; 4, shaftless spiral blade; 5, feed bin; 6, drive motor; 7, water immersion sensor; 8, one-way discharge door; 9, protective cover; 10, drill rig. Specific implementation mode

[0040] Next, the technical solutions in the embodiments of the present application will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments of the present application, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present application.

[0041] In the description of the invention, it should be understood that the orientation or positional relationship indicated by terms such as "front", "rear", "upper", "lower", "left", "right", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present invention.

[0042] In the prior art, when constructing a tunnel in a mountain body, it is necessary to drill holes on the side wall of the mountain body. Usually, the depth of the hole is about 2-3 m, and the inner diameter of the hole is 20-25 cm. When drilling operations are carried out through a spiral drill rod, the problem of mountain water gushing out occurs in the area where the mountain water is rich. If it is not blocked and treated in time, this hole cannot be used. In order to block the mountain water, the conventional method is to retract the drill and then enter again for blocking. However, this is likely to delay time and increase the risk of mountain water gushing. To solve this problem, as Figure 1 shown, the applicant reforms the tunnel drilling construction method. This embodiment discloses a construction method for preventing water penetration in mountain tunnels, including the following steps:

[0043] S10. Prepare several sealing strips in the factory in advance;

[0044] The sealing strip, as a sealing material, needs to be prepared in advance because of water leakage that needs to be sealed in a timely manner, and it also needs to be convenient for subsequent transportation by the shaftless spiral blade. It is made of a water leakage sealing material in the shield field. In this embodiment, the sealing strip is made of 45 parts of sulfoaluminate cement, 20 parts of bentonite, 10 parts of superabsorbent resin, 5 parts of polypropylene fiber, 5 parts of nano-silica, 3 parts of slow-release coagulant, 2 parts of plasticizer, and 12 parts of deionized water. The polypropylene fiber enables the sealing strip to have sufficient anti-bending ability. The bentonite is a plastic carrier to prevent the material from hardening prematurely. The superabsorbent resin can swell in rainwater to form a water-stop layer, ensuring that the sealing strip can quickly seal when it enters the water leakage area. The plasticizer can improve the extrusion molding performance for the later production of the sealing strip by an extruder;

[0045] In this embodiment, the specific preparation process of the sealing strip is as follows:

[0046] S1001. Add the sulfoaluminate cement and bentonite into a mixer and mix at a speed of 30 rpm for 15 minutes to form a uniform base material;

[0047] S1002. Add the superabsorbent resin, polypropylene fiber, and nano-silica in sequence and mix at a speed of 60 rpm for 5 minutes to form a mixed material;

[0048] S1003. Prepare an aqueous solution of the slow-release coagulant and plasticizer, and synchronously inject the aqueous solution into the mixed material in S1002 through a spray system;

[0049] S1004. After stirring and mixing, form a plastic paste, and extrude the plastic paste into an initial strip-shaped material through a screw extruder;

[0050] S1005. Send the initial strip-shaped material into the curing area, set the environment to a temperature of 60°C ± 2°C and a humidity of 95% RH for steam curing, and then naturally dry until the moisture content ≤ 5% to finally form a sealing strip. The length of the sealing strip is controlled to be 20 - 40 cm, which is convenient for construction workers to carry;

[0051] The sealing strip produced by the above preparation method has good bending resistance and excellent toughness, and can be transported by a shaftless spiral blade. Then, the sealing strip is detected by the volume displacement method. Its immersion swelling rate is about 35% in 1 hour, meeting the requirements for sealing use;

[0052] S20. As Figure 2 shown, a feeding cavity 1 is arranged along the axial direction in the spiral drill pipe. The drill rig 10 enters the site, and the spiral drill pipe is connected to the power head 2 of the drill rig 10;

[0053] In this step, in order to enable the plugging strip to be quickly conveyed in the feeding chamber 1, a shaftless spiral blade 4 applicable to the conveyance of strip materials in the prior art can be used for conveyance. The specific installation process of the shaftless spiral blade 4 is as follows:

[0054] As Figures 3 - 4 shown, first, a feed bin 5 is installed at a position near the rear end of the side wall of the auger rod. The feed bin 5 communicates with the feeding chamber 1, and a discharge port is provided at a position near the front end of the feeding chamber 1; a rotary shaft with a diameter of 10 cm is welded to the front end of the shaftless spiral blade 4, and a drive shaft is welded to the rear end of the shaftless spiral blade 4;

[0055] Then, the rotary shaft at the front end of the shaftless spiral blade 4 is rotatably connected to the front end of the feeding chamber 1 through a bearing assembly. The drive shaft at the rear end of the shaftless spiral blade 4 penetrates through the rear end of the feeding chamber 1 and extends to the outside of the auger rod. The drive shaft and the rear end of the feeding chamber 1 are rotatably connected through a bearing assembly;

[0056] Finally, a drive motor 6 is installed outside the auger rod, and the drive motor 6 is fixed to the drive shaft through a coupling;

[0057] In order to facilitate the monitoring of mountain water, on the auger rod, the area between the drill bit and the outer spiral blade 3 is defined as a seepage monitoring area, and a one-way discharge door 8 is provided in the seepage monitoring area. The one-way discharge door 8 communicates with the discharge port of the feeding chamber 1. The one-way discharge door 8 can be a conventional electric gate or a common gate that can be turned outwards, so it belongs to conventional technology and will not be described in detail here. A conventional seepage monitoring module is installed in the seepage monitoring area;

[0058] The installation of this seepage monitoring module includes the following steps:

[0059] S201. A sensor groove is machined in the seepage monitoring area;

[0060] S202. An immersion sensor 7 is installed in the sensor groove;

[0061] S203. A protective cover 9 with grid holes is assembled on the sensor groove. The protective cover 9 can protect the immersion sensor 7, and at the same time, the immersion sensor 7 detects whether there is water leakage through the grid holes at all times;

[0062] S30. Measure and set out the drilling position and drive in a mark;

[0063] S40. Start the rotary drilling rig, align the auger rod with the drilling position for drilling construction, control the rotation speed to 10 - 15 revolutions per minute, and the drilling speed to 0.5 - 0.8 meters per minute; while the auger rod forms a hole in the mountain body during drilling, the outer spiral blade 3 on the outside of the auger rod discharges the mountain debris;

[0064] S50. During the drilling construction process, when mountain water leakage occurs at a certain location and the water leakage phenomenon is detected by the water immersion sensor, the drilling work of the auger rod is stopped, and the drive motor is used to control the rotation of the shaftless spiral blade 4, and a number of sealing strips are transported to the feeding chamber 1 through the feeding bin 5;

[0065] S60. With the rotation and transportation of the shaftless spiral blade 4, the sealing strips are conveyed to the front end of the feeding chamber 1 close to the drill bit, and then discharged into the hole through the one-way discharge door. After the sealing strips come into contact with water, they expand and then seal the mountain water leakage point;

[0066] S70. When the water blocking is completed, wait statically for 0.5 - 1 h. After there is no more water leakage, proceed with the subsequent construction.

[0067] Through the above-mentioned construction method for preventing water penetration in mountain tunnels during drilling, when mountain water leakage occurs during the drilling construction process, the auger rod work is stopped, a number of sealing strips are filled into the feeding chamber 1, the sealing strips are conveyed to the position close to the drill bit through the feeding chamber 1, and then the sealing strips are discharged into the hole to seal the mountain water leakage point, replacing the previous sealing method that requires redrilling and secondary pipe lowering. It can quickly carry out sealing, has high construction efficiency, avoids the problem of water spraying during redrilling, and reduces the construction cost.

Claims

1. A construction method for preventing water penetration during drilling of mountain tunnels, characterized in that, It includes the following steps: S10. Prepare several plugging strips in the factory in advance. The plugging strips are strip-shaped, and the length of the plugging strips is 20 - 40 cm. The plugging strips are made of sulfoaluminate cement, bentonite, superabsorbent resin, polypropylene fiber, nano-silica, slow-release coagulant and plasticizer. S20. A feeding cavity (1) is arranged along the axial direction in the auger drill pipe. The drill rig (10) enters the site, and the auger drill pipe is connected to the power head (2) of the drill rig (10). The area between the drill bit and the outer spiral blade (3) is defined as the water seepage monitoring area, and a water seepage monitoring module is provided in the water seepage monitoring area in advance. A one-way discharge door (8) is provided in the water seepage monitoring area in advance, and the one-way discharge door (8) communicates with the feeding cavity. S30. Measure and set out the drilling position on the mountain body and drive in a mark. S40. Start the drill rig, align the drill bit of the auger drill pipe with the drilling position for drilling construction. While the auger drill pipe drills into the mountain body to form a hole, the outer spiral blade (3) on the outside of the auger drill pipe discharges the mountain debris. S50. During the drilling construction, when mountain water leakage occurs, the water seepage detection module monitors that water seeps into the hole, stops the drilling work of the auger drill pipe, and fills several plugging strips into the feeding cavity (1). S60. Transport the plugging strips through the feeding cavity (1) to a position close to the drill bit, and then discharge the plugging strips into the hole to plug the mountain water leakage point. When the plugging strip enters the feeding cavity, it is transported to a position close to the drill bit by the conveying method of a shaftless spiral blade, and then the plugging strip is discharged into the drill hole through the one-way discharge door (8) to plug the mountain water leakage point.

2. The construction method for preventing water penetration during mountain tunnel drilling according to claim 1, characterized in that, The preparation of the plugging strip includes the following steps: S1001. Add sulfoaluminate cement and bentonite to a mixer and mix to form a uniform base material. S1002. Add superabsorbent resin, polypropylene fiber and nano-silica in sequence and mix to form a mixture. S1003. Configure the slow-release coagulant and plasticizer into an aqueous solution, and synchronously inject the aqueous solution into the mixture in S1002 through a spraying system. S1004. After stirring and mixing, form a plastic paste, and extrude the plastic paste into an initial strip-shaped material through a screw extruder. S1005. Carry out steam curing on the initial strip-shaped material, and then naturally dry it until the moisture content ≤ 5% to finally form a plugging strip.

3. The construction method for preventing water penetration during mountain tunnel drilling according to claim 1 is characterized in that, The installation of the water seepage monitoring module includes the following steps: S201. Process a sensor groove in the water seepage monitoring area. S202. Install a water immersion sensor (7) in the sensor groove. S203. Assemble a protective cover (9) with grid holes on the sensor groove.

4. The construction method for preventing water penetration during mountain tunnel drilling according to any one of claims 1 to 3, characterized in that, In step S40, the rotation speed of the auger drill pipe is controlled to 10 - 15 revolutions per minute.

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