Advanced grouting reinforcement method

Abstract

The invention discloses an advanced grouting reinforcement method. The method comprises the steps that S1, drill holes are formed in the periphery of a roadway to be excavated in advance; s2, high-pressure water is injected into the drill hole to open an original closed crack in the surrounding rock; and S3, an ultrasonic transducer is placed in the drill hole, the ultrasonic transducer generates ultrasonic waves to enable water in the crack to vibrate, and meanwhile, grouting is conducted in the drill hole adjacent to the drill hole where the ultrasonic transducer is placed. According to the advanced grouting reinforcement method, the grouting range is widened, the grouting amount is increased, and the forming quality and stability of the inner section of the roadway are guaranteed.

Description

Technical Field

[0001] The invention relates to the technical field of deep earth energy development engineering, and in particular to an advanced grouting reinforcement method. Background Art

[0002] When the excavation face of a roadway (tunnel) encounters a broken zone, the roof and side of the roadway (tunnel) are prone to large-scale falling before anchor rods and cables are used for support, which seriously affects the quality of cross-section forming and greatly reduces the support speed and effect.

[0003] In the related technology, in order to ensure the quality and stability of the cross-section forming, the roadway (tunnel) is generally treated in advance, that is, the roadway is directly grouting reinforced. However, since the surrounding rock to be excavated at the excavation face is in a stress concentration area, under the action of high stress, the cracks at the cross-section are easily squeezed and closed, resulting in a significant reduction in the opening of the cracks, making it difficult for the slurry to enter the cracks, affecting the grouting effect, and it is difficult to solve the phenomenon of surrounding rock falling during the roadway (tunnel) excavation process. Summary of the invention

[0004] The present invention aims to solve one of the technical problems in the related art at least to a certain extent. To this end, an embodiment of the present invention provides an advanced grouting reinforcement method.

[0005] The advanced grouting reinforcement method of the embodiment of the present invention comprises:

[0006] S1. Drill holes in advance around the tunnel to be excavated;

[0007] S2, injecting high-pressure water into the borehole to open the original closed cracks in the surrounding rock;

[0008] S3, placing an ultrasonic transducer in the borehole, the ultrasonic transducer generating ultrasonic waves to vibrate the water in the crack, and injecting grout into the borehole adjacent to the borehole in which the ultrasonic transducer is placed.

[0009] The advance grouting reinforcement method of the embodiment of the present invention is to first open holes in advance around the tunnel to be excavated, and inject high-pressure water into the holes so that the high-pressure water enters the original cracks in the surrounding rock through the cracks on the inner wall of the holes to open the original closed cracks in the surrounding rock. An ultrasonic transducer is used to generate ultrasonic waves to the high-pressure water in the cracks so that the water in the cracks can maintain continuous vibration to ensure that the cracks are always in an open state. At the same time, grouting is injected into adjacent holes to facilitate the entry of slurry into the cracks, thereby increasing the grouting amount and grouting range, ensuring the quality and stability of the cross-section forming in the tunnel, and thus improving the tunneling speed and support effect.

[0010] In some embodiments, sand and gravel are mixed in the high-pressure water, and the sand and gravel remain in the cracks.

[0011] In some embodiments, S1 includes: opening a plurality of the boreholes at intervals around the tunnel, the distance between adjacent boreholes is greater than 0 and less than or equal to 2m, the diameter of the borehole is greater than or equal to 100mm, and the depth of the borehole is greater than or equal to 50m.

[0012] In some embodiments, the S2 includes:

[0013] S21, injecting high-pressure water from the bottom of the borehole to the opening of the borehole in a stepwise backward manner along the extension direction of the borehole;

[0014] S22, a hole sealer is arranged in the borehole, the hole sealer moves from the bottom of the borehole to the opening of the borehole along the extension direction of the borehole, and the hole sealer is used to seal the high-pressure water in the borehole.

[0015] In some embodiments, in S21, high-pressure water is injected into the borehole once every 2m-3m along the extension direction of the borehole.

[0016] In some embodiments, before S3 and after S2, the boreholes other than the boreholes not provided with the ultrasonic transducer and the boreholes to be grouting are blocked.

[0017] In some embodiments, S3 includes: injecting slurry from the bottom of the borehole to the opening of the borehole in a segmented backward manner along the extension direction of the borehole, and the ultrasonic transducer moves from the bottom of the borehole to the opening of the borehole along the extension direction of the borehole in the adjacent borehole and is synchronized with the grouting.

[0018] In some embodiments, in S3, slurry is injected into the borehole once every 5m-20m along the extension direction of the borehole.

[0019] In some embodiments, the depth of the slurry used to seal the borehole is greater than or equal to 200 mm in the extension direction of the borehole.

[0020] In some embodiments, the pressure of the high-pressure water is greater than or equal to 20 MPa, and the flow rate of the high-pressure water is greater than or equal to 1.5 m 3 / min, when grouting into the borehole, the pressure of the slurry is greater than or equal to 40MPa, and the rated flow rate of the slurry is greater than or equal to 1m 3 / min. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a schematic diagram of the advance grouting reinforcement method according to an embodiment of the present invention.

[0022] Figure 2 It is a schematic diagram of grouting in the advanced grouting reinforcement method according to an embodiment of the present invention.

[0023] Figure 3 It is a schematic diagram of the movement of the hole sealer in the advance grouting reinforcement method according to an embodiment of the present invention.

[0024] Figure numerals: 1, drill hole; 2, crack; 3, ultrasonic transducer; 31, probe; 4, high-pressure water injection pump; 5, hydraulic grouting pump; 51, grouting pipe; 6, hole sealer; 7, surrounding rock. DETAILED DESCRIPTION

[0025] Embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and intended to be used to explain the present invention, but should not be understood as limiting the present invention.

[0026] like Figure 1-3 As shown, the advanced grouting reinforcement method of the embodiment of the present invention includes:

[0027] S1. Drill holes 1 are opened in advance around the tunnel to be excavated.

[0028] S2. Inject high-pressure water into the borehole 1 to open the closed cracks 2 in the surrounding rock 7. Specifically, high-pressure water is injected into the borehole 1 by a high-pressure water injection pump 4. The pressure of the high-pressure water is greater than or equal to 20 MPa, and the flow rate of the high-pressure water is greater than or equal to 1.5 m 3 / min, so that it is easy to enter the original cracks 2 in the surrounding rock 7 through the cracks 2 on the inner wall of the borehole 1 to open the original closed cracks in the surrounding rock 7, and the cracks 2 are divergent.

[0029] S3. An ultrasonic transducer 3 is placed in the borehole 1. The ultrasonic transducer 3 generates ultrasonic waves to vibrate the water in the crack 2. At the same time, grouting is injected into the borehole 1 adjacent to the borehole 1 in which the ultrasonic transducer 3 is placed.

[0030] Specifically, a high-power, large-amplitude ultrasonic transducer 3 is placed in the borehole 1. The ultrasonic transducer 3 can generate high-energy ultrasonic waves. Based on the water medium in the crack 2, the water in the crack 2 can continuously maintain high-frequency vibrations, ensuring that the crack 2 is always in an open state. Specifically, the transmitter power is greater than or equal to 185KW, and the transducer electrical power density is 32KW.

[0031] Specifically, while the ultrasonic transducer 3 is vibrating, in the borehole 1 adjacent to the borehole 1 in which the ultrasonic transducer 3 is placed, an ultra-high pressure, large flow hydraulic grouting pump 5 is used to perform high pressure splitting grouting into the borehole 1 through a grouting pipe 51, and the rated grouting pressure of the hydraulic grouting pump 5 is greater than or equal to 40 MPa, and the rated flow rate is greater than or equal to 1m 3 / min, the grouting material is micro-nano high-performance double-liquid grouting material, the particle size is D 95 Less than 5μm, bonding strength with coal rock ≥3.5MPa, 2h compressive strength ≥10MPa, initial setting time 30min-1h, ensuring that the slurry can further expand the crack 2 when entering the crack 2, thereby increasing the grouting amount and grouting range.

[0032] The advance grouting reinforcement method of the embodiment of the present invention is to first open a borehole 1 in advance around the tunnel to be excavated, and inject high-pressure water into the borehole 1 so that the high-pressure water can enter the original cracks in the surrounding rock 7 through the cracks on the inner wall of the borehole 1 to open the original closed cracks 2 in the surrounding rock 7, and generate ultrasonic waves to the high-pressure water in the cracks 2 through the ultrasonic transducer 3 to keep the water in the cracks 2 vibrating continuously to ensure that the cracks 2 are always in an open state. At the same time, grouting is injected into the adjacent borehole 1 to facilitate the slurry to enter the cracks 2, thereby increasing the grouting amount and grouting range, ensuring the quality and stability of the cross-section forming in the tunnel, thereby improving the tunneling speed and support effect.

[0033] In some embodiments, sand and gravel are mixed in the high-pressure water, and the sand and gravel remain in the crack 2. Specifically, when the high-pressure water enters the crack 2, it will carry the sand and gravel into the crack 2, and the crack 2 is supported by the sand and gravel to ensure the opening of the crack 2, so that the slurry can enter the crack 2 during the subsequent grouting.

[0034] In some embodiments, S1 includes: a plurality of bore holes 1 are opened at intervals around the tunnel, and the distance between adjacent bore holes 1 is greater than 0 and less than or equal to 2m. When high-pressure water is injected into one of the bore holes 1 and the high-pressure water is continuously vibrated in the crack 2 through the ultrasonic transducer 3, the crack 2 in the bore hole 1 adjacent to one of the bore holes 1 is usually also susceptible to vibration, thereby ensuring the opening of the crack 2 and extending the duration of the cracking of the crack 2.

[0035] In some embodiments, the aperture of the borehole 1 is greater than or equal to 100 mm, and the depth of the borehole 1 is greater than or equal to 50 m, which is convenient for injecting high-pressure water and slurry into the borehole 1 and setting an ultrasonic transducer 3 in the borehole 1 to ensure that the borehole 1 can accommodate more slurry and ensure the amount of injected slurry.

[0036] In some embodiments, S2 includes:

[0037] S21. High-pressure water is injected from the bottom of the borehole 1 to the opening of the borehole 1 in a segmented backward manner along the extension direction of the borehole 1 to ensure the pressure of the high-pressure water injected into the borehole 1 each time, so that the high-pressure water can expand the cracks 2 in the surrounding rock 7 in segments, thereby ensuring the density and opening of the cracks 2.

[0038] S22 , a hole sealer 6 is arranged in the borehole 1 , and the hole sealer 6 moves from the bottom of the borehole 1 to the opening of the borehole 1 along the extension direction of the borehole 1 , and the hole sealer 6 is used to seal the high-pressure water in the borehole 1 .

[0039] Specifically, each time high-pressure water is injected into the borehole 1, the borehole 1 is sealed by the sealer 6, and the sealer 6 gradually moves from the bottom of the borehole 1 to the opening of the borehole 1 along the extension direction of the borehole 1 to ensure that the pressure of the high-pressure water can be released on the inner wall surface of the borehole 1 without being easily dissipated, thereby ensuring the effect of high-pressure water expanding the crack 2.

[0040] In some embodiments, in S21, high-pressure water is injected into the borehole 1 once every 2m-3m along the extension direction of the borehole 1, thereby ensuring the effect of high-pressure water on expanding the original cracks 2 in the surrounding rock 7 and the uniformity of the cracks 2, thereby ensuring the diffusion range of the slurry when grouting into the borehole 1, improving the reinforcement and support of the slurry to the cross-section in the tunnel, and ensuring the forming quality of the cross-section in the tunnel.

[0041] In some embodiments, before S3 and after S2, the boreholes 1 other than the boreholes 1 without ultrasonic transducers 3 and the boreholes 1 to be grouted are blocked. Specifically, the other boreholes 1 can be blocked by cotton yarn or the like to prevent the slurry from leaking out of the other boreholes 1 when the boreholes 1 are grouted.

[0042] In some embodiments, S3 includes: injecting slurry from the bottom of the borehole 1 to the opening of the borehole 1 along the extension direction of the borehole 1 in a segmented backward manner to ensure the pressure of the slurry injected into the borehole 1 each time, so that the slurry can fill the cracks 2 and ensure the grouting range of the slurry. At the same time, the ultrasonic transducer 3 has a probe 31, and the probe 31 moves from the bottom of the borehole 1 to the opening of the borehole 1 along the extension direction of the borehole 1 in the adjacent borehole 1 and is synchronized with the grouting to ensure that the slurry can more easily enter the cracks 2 during grouting.

[0043] In some embodiments, in S3, slurry is injected into the borehole 1 every 5m-20m along the extension direction of the borehole 1. Specifically, after each injection of slurry into the borehole 1, the borehole 1 is sealed by the sealer 6, and the sealer 6 gradually moves from the bottom of the borehole 1 to the opening of the borehole 1 along the extension direction of the borehole 1 (e.g., Figure 3 The slurry is directed in the direction indicated by the arrow in the middle) to ensure the pressure of the slurry when grouting in the borehole 1, expand the diffusion range of the slurry, and the slurry can further open the opening and extension length of the crack 2, increase the grouting amount, and ensure the reinforcement and support of the slurry on the section in the tunnel and the molding quality of the section in the tunnel.

[0044] In some embodiments, the depth of the slurry used to seal the borehole 1 is greater than or equal to 200 mm in the extension direction of the borehole 1. Specifically, the length of the slurry after solidification in the borehole 1 is greater than or equal to 200 mm in the extension direction of the borehole 1, ensuring that the solidified slurry reinforces and supports the cross-section in the tunnel, improves the molding quality of the cross-section in the tunnel, and improves the excavation speed and support effect.

[0045] In the description of the present invention, it is to be understood that the terms “center”, “longitudinal”, “lateral”, “length”, “width”, “thickness”, “up”, “down”, “front”, “back”, “left”, “right”, “vertical”, “horizontal”, “top”, “bottom”, “inside”, “outside”, “clockwise”, “counterclockwise”, “axial”, “radial”, “circumferential”, etc., indicating orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0046] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0047] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral one; it can be a mechanical connection, an electrical connection, or communication with each other; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0048] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being "above", "above" or "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" or "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0049] In the present invention, the terms "one embodiment", "some embodiments", "examples", "specific examples", or "some examples" etc. mean that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the described specific features, structures, materials or characteristics may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0050] Although the above embodiments have been shown and described, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations on the present invention. Changes, modifications, substitutions and variations of the above embodiments by those of ordinary skill in the art are all within the scope of protection of the present invention.

Claims

1. A method for pre-grouting reinforcement, characterized in that: include: S1. Drill holes (1) are opened in advance around the tunnel to be excavated; S2, injecting high-pressure water into the borehole (1) to open the original closed cracks (2) in the surrounding rock (7); S3. An ultrasonic transducer (3) is placed in the borehole (1), wherein the ultrasonic transducer (3) generates ultrasonic waves to vibrate the water in the crack (2) opened by the high-pressure water, and at the same time, grouting is injected into the borehole (1) adjacent to the borehole (1) in which the ultrasonic transducer (3) is placed.

2. The advanced grouting reinforcement method according to claim 1, characterized in that: The high-pressure water is mixed with sand and gravel, and the sand and gravel remain in the crack (2).

3. The advanced grouting reinforcement method according to claim 1, characterized in that: The S1 comprises: a plurality of the boreholes (1) are opened at intervals around the tunnel, the distance between adjacent boreholes (1) is greater than 0 and less than or equal to 2 m, the diameter of the borehole (1) is greater than or equal to 100 mm, and the depth of the borehole (1) is greater than or equal to 50 m.

4. The advanced grouting reinforcement method according to claim 1, characterized in that: The S2 includes: S21, injecting high-pressure water from the bottom of the borehole (1) toward the opening of the borehole (1) in a stepwise backward manner along the extension direction of the borehole (1); S22. A hole sealer (6) is arranged in the borehole (1), and the hole sealer (6) moves from the bottom of the borehole (1) to the opening of the borehole (1) along the extension direction of the borehole (1), and the hole sealer (6) is used to seal high-pressure water in the borehole (1).

5. The advanced grouting reinforcement method according to claim 4, characterized in that: In the step S21, high-pressure water is injected into the borehole (1) once every 2m to 3m along the extension direction of the borehole (1).

6. The advanced grouting reinforcement method according to claim 1, characterized in that: Before S3 and after S2, the boreholes (1) other than the borehole (1) not provided with the ultrasonic transducer (3) and the borehole (1) to be grouting are blocked.

7. The advanced grouting reinforcement method according to claim 1, characterized in that: The S3 comprises: injecting slurry from the bottom of the borehole (1) to the opening of the borehole (1) in a segmented backward manner along the extension direction of the borehole (1); the ultrasonic transducer (3) moves from the bottom of the borehole (1) to the opening of the borehole (1) in the adjacent borehole (1) along the extension direction of the borehole (1) and is synchronized with the grouting.

8. The advanced grouting reinforcement method according to claim 7, characterized in that: In S3, slurry is injected into the borehole (1) once every 5m-20m along the extension direction of the borehole (1).

9. The advanced grouting reinforcement method according to claim 7, characterized in that: The depth of the slurry used to seal the borehole (1) is greater than or equal to 200 mm in the extension direction of the borehole (1).

10. The advanced grouting reinforcement method according to claim 1, characterized in that: The pressure of the high-pressure water is greater than or equal to 20 MPa, and the flow rate of the high-pressure water is greater than or equal to 1.5 m 3 / min, when grouting into the borehole (1), the pressure of the slurry is greater than or equal to 40MPa, and the rated flow rate of the slurry is greater than or equal to 1m 3 / min.

Images