Roof water-containing roadway anchor cable hole sealing device and method

Abstract

The invention relates to a roof water-containing roadway anchor cable hole sealing device and method, and belongs to the technical field of roadway supporting. The hole sealing method comprises the following steps: (1) calculating the hole expanding height and the slurry diffusion radius according to the section of a roadway; (2) designing a roadway roof support form and an interval row distance; (3) a drill bit constructs an anchor cable drill hole; (4) chambering the outer side of the anchor cable drill hole by using an anchor cable drilling machine; (5) supporting the anchoring agent by using an anchor cable, and slowly feeding into the drill hole; (6) a hole sealing and grouting device is installed, specifically, a hole sealing device, a tray and a lock are sequentially arranged at the tail of the anchor cable; and (7) the anchor cable is tensioned and pre-tightened through a tensioning machine tool, materials in the hole sealing device are rapidly mixed and pressed to enter cracks of the roadway surrounding rock broken area, the materials are rapidly hardened into high-strength sealing materials, and therefore the effective water plugging effect is achieved. After the grouting hole sealing method is used, the strength of rock mass in a broken area of the roadway roof is remarkably improved, and the overall stability of the roadway roof is improved.

Description

Technical Field

[0001] This invention relates to the technical field of roadway support, specifically to a sealing device and method for anchor cable holes in a water-bearing roadway with a roof. Background Technology

[0002] During the excavation of deep roadways, the continuous influence of "high temperature, high humidity, high temperature, high wind speed, and high ground disturbance" factors leads to intense mine pressure, severe deformation and damage of the surrounding rock, and frequent failure of support components. This results in a large number of loose, fractured, and difficult-to-support roadways requiring frequent repairs. Roof falls are particularly prominent during roadway excavation and frequent repairs. Anchor cable support technology has been widely applied in coal mine roadway support. This technology injects a cementing grout into loose, fractured rock containing numerous fissures, re-cementing the fractured rock into a stronger, consolidated mass. This not only improves the physical and mechanical properties of the fractured surrounding rock but also significantly increases its cohesion and internal friction angle, thereby enhancing the strength and overall bearing capacity of the surrounding rock and contributing to its long-term stability. However, when the roadway roof is covered by an aquifer and the ends of the anchor cable boreholes extend into the water-rich area, water from the roof will continuously seep along the anchor cable boreholes and, under the guidance of the steel strips or reinforced beams, form a water-sprinkling zone on the roadway roof. This water-sprinkling phenomenon not only worsens the underground working environment but also poses a serious threat to the safety of roadway construction.

[0003] Currently, grouting anchor cables are commonly used to address the problem of water seepage from the roof of roadways. While grouting anchor cables can effectively control water seepage during the roadway excavation stage, during the mining phase, the roof cracks will further expand and penetrate the aquifer due to the pressure from the advance support, causing water seepage to recur. Summary of the Invention

[0004] To address the problem of water seepage from the roof of water-bearing roadways during existing working face mining, this invention provides a sealing device and method for anchor cable holes in water-bearing roadways to solve the aforementioned problem. The invention first calculates the enlargement height and slurry diffusion radius based on the roadway cross-section and designs the spacing between anchor cables. Next, anchor cable holes are drilled and enlarged according to the calculated enlargement height. Then, the anchor cables are anchored, and a sealing device, tray, and lock are sequentially installed at the tail end of the anchor cables. Finally, the anchor cables are tensioned, causing the sealing device to fracture due to pressure against the surrounding rock. The material inside the sealing device rapidly mixes and is pressurized into the fractured areas of the surrounding rock in the roadway, quickly hardening into a high-strength sealing material, thereby achieving an effective water-blocking effect.

[0005] The technical solution of this invention is as follows: A method for sealing anchor cable holes in a water-bearing roadway in the roof includes the following steps: (1) Calculate the borehole height and slurry diffusion radius based on the roadway cross-section; (2) Design the roof support method and spacing of the roadway; (3) Construction of anchor cable drilling: Anchor cable drilling is carried out using an anchor cable drilling machine with a Φ27mm drill bit; (4) Enlarging the hole: Use an anchor cable drilling machine with a Φ75mm drill bit to enlarge the outer side of the anchor cable hole; (5) Anchoring: When installing anchor cables, a special mixing driver is installed at the lower end of the anchor cable. The anchor cable is used to push the anchoring agent into the borehole slowly to ensure that all the anchoring agent is delivered to the bottom of the hole. The hexagonal head at the tail of the special mixing driver is inserted into the anchor cable drilling machine and mixed while pushing it forward. (6) Install the sealing and grouting device: Install the sealing device, tray and lock in sequence at the tail of the anchor cable; (7) Tensioning anchor cable: The tensioning equipment is installed on the exposed section of the anchor cable. The anchor cable is tensioned and pre-tightened by the tensioning equipment, so that the sealing device is squeezed and broken by the surrounding rock. The material in the sealing device is quickly mixed and pressed into the fracture zone of the surrounding rock in the roadway, and quickly hardens into a high-strength sealing material, thereby achieving the effect of effectively blocking water.

[0006] Furthermore, in step (1), the hole enlargement height R b The calculation formula is shown in equation (I): (I) Where: reduction factor N The formula for calculating 0 is shown in equation (II): (II) In the formula: Γ t For the timing of tunnel support, when the support time after excavation is less than 8 hours, Γ t Taking 1, when the support time after excavation is 8~16h, Γ t Taking 0.75, when the support time after excavation is 16~24h, Γ t Take 0.5, when the support time after excavation is greater than 24 hours, Γ t Take 0.25; Q c This is a coefficient representing the complexity of the geological structure of the tunnel area. When the geological structure is simple... Q c When the value is 0.25, and the geological structure is of medium quality, Q c When the geological structure is complex, a value of 0.5 is used. Q c When the value is 0.75, and the geological structure is extremely complex, Q c Take 1; R 0 represents the radius of the tunnel; γ Unit weight of the rock strata; H To deepen the tunnel; CThe cohesion of the top strata; φ The internal friction angle of the top rock strata.

[0007] Furthermore, the slurry diffusion radius R k The calculation formula is shown in equation (III): (III) In the formula: P The pressure of the slurry; b The width of the crack; τ The yield strength of the slurry; r 0 represents the radius of the outer borehole.

[0008] Furthermore, the spacing between the anchor cables is ≤2. R b , R b This refers to the height of the enlarged hole.

[0009] A sealing device for anchor cable holes in a water-bearing roadway includes an anchor cable and a sealing device fitted onto the anchor cable; the center of the sealing device is a through anchor cable borehole; a tray is provided on one side of the sealing device along the anchor cable direction; a bladder is provided inside the sealing device, and the bladder is filled with sealing material; a lock is provided on the side of the tray opposite the sealing device.

[0010] Furthermore, the sealing material includes chemical material A and chemical material B; chemical material A and chemical material B are mixed and then solidified to form a sealing material.

[0011] Furthermore, the sealing device is internally divided into multiple adjacent spaces by multiple partitions, and chemical material A and chemical material B are placed in adjacent spaces.

[0012] Furthermore, a sealing strip is provided at the edge of the anchor cable borehole.

[0013] Furthermore, the sealing device has an outer diameter of 73mm, an inner diameter of 22mm, and a length of ( ). R b +50) mm, R b This refers to the height of the enlarged hole.

[0014] Furthermore, chemical material A is Marisan A-material, and chemical material B is Marisan B-material. Marisan is a silicate-modified polyurethane material, a chemically reactive polymer composed of two components: Marisan A-material and Marisan B-material. The solidified body formed after mixing and curing can bind previously loose and fragmented coal and rock masses into a unified whole, sealing cracks in the coal and rock mass, improving stress distribution, and enhancing the bearing capacity of the coal and rock mass.

[0015] The beneficial effects of this invention are as follows: The sealing method for water-bearing roadways provided by this invention differs from traditional grouting anchor cables. Its operation is simple, significantly reducing the grouting construction time of anchor cables, requiring less grout, and providing better water-blocking effects during working face mining. Using this grouting sealing method, the space between the anchor cable and the borehole can be sealed, as well as the cracks around the borehole, significantly improving the strength of the fractured rock mass in the roadway roof and enhancing the overall stability of the roadway roof. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 This is a schematic diagram of the overall structure of the present invention.

[0018] Figure 2 This is a schematic diagram of the drilling structure of the present invention.

[0019] Figure 3 This is a schematic diagram of the sealing device of the present invention.

[0020] Figure 4 This is a construction diagram of the present invention.

[0021] In the diagram: 1-Anchor cable; 2-Sealing device; 3-Tray; 4-Lock; 5-Anchor cable borehole; 6-Sealing borehole; 7-Rock fissure; 8-Bag; 9-Chemical material A; 10-Chemical material B; 11-Sealing strip; 12-Anchor cable borehole; 13-Sealing material. Detailed Implementation

[0022] To enable those skilled in the art to better understand the technical solutions of this invention, the technical solutions in the embodiments of this invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of this invention, and not all embodiments. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of this invention.

[0023] Example 1 A certain mine includes the 1512 auxiliary haulage roadway, which is located within the No. 5 coal seam. The No. 5 coal seam is 2.01–3.32 m thick, with a dip angle of 5–10°, averaging 7°. The immediate roof is an average of 2.11 m thick siltstone; the main roof is an average of 13.35 m thick gravelly coarse sandstone, which is an aquifer; and the immediate floor is an average of 7.1 m thick fine sandstone, cemented with argillaceous clay. The 1512 auxiliary haulage roadway is designed as a straight-walled, three-center arch roadway, situated within the coal seam and soft floor rock, supported by a roof coal seam with an average thickness of 1.2 m. Figures 1-3 As shown, the anchor cable hole sealing device for the water-bearing roadway includes an anchor cable and a sealing device fitted onto the anchor cable; the center of the sealing device is a through-hole of the anchor cable; a tray is provided on one side of the sealing device along the anchor cable direction; the sealing device has an outer diameter of 73mm, an inner diameter of 22mm, and a length of ( R b +50) mm; the sealing device has a bag inside, which contains chemical material A and chemical material B respectively. Chemical material A is Marisan A material and chemical material B is Marisan B material. After mixing, chemical material A and chemical material B solidify to form a sealing material; the sealing device has multiple partitions inside, and chemical material A and chemical material B are placed in adjacent partitions; a lock is provided on the side of the tray opposite to the sealing device; a sealing strip is provided on the edge of the anchor cable drill hole.

[0024] A method for sealing the holes of grouting anchor cables in the roof slab, such as Figures 1-4 As shown, the steps are as follows: (1) Calculate the borehole height and slurry diffusion radius based on the roadway cross-section; The formula for calculating the hole enlargement height is shown in equation (I): (I) Where: reduction factor N The formula for calculating 0 is shown in equation (II): (II) In the formula: Γ t For the timing of tunnel support, when the support time after excavation is less than 8 hours, Γ t Taking 1, when the support time after excavation is 8~16h, Γ t Taking 0.75, when the support time after excavation is 16~24h, Γ t Take 0.5, when the support time after excavation is greater than 24 hours, Γ t Take 0.25; Q c This is a coefficient representing the complexity of the geological structure of the tunnel area. When the geological structure is simple... Q c When the value is 0.25, and the geological structure is of medium quality, Q cWhen the geological structure is complex, a value of 0.5 is used. Q c When the value is 0.75, and the geological structure is extremely complex, Q c Take 1; R 0 represents the radius of the tunnel; γ Unit weight of the rock strata; H To deepen the tunnel; C The cohesion of the top strata; φ The internal friction angle of the top rock strata.

[0025] Based on the actual site conditions, the support time after excavation is generally less than 8 hours, i.e., Γ t Take 1; the geological structure of the tunnel area is simple, that is... Q c If we take 0.25, then the reduction factor is... N 0 is 4, and the radius of the alley is... R 0 is 2.5m, rock stratum unit weight γ 25kN / m 3 The tunnel is buried deep H The cohesion of soft rock is 259.9m. C The internal friction angle of the soft rock is 4.79 MPa. φ It is 35°. N 0 = 4 R 0 = 2.5m γ =25kN / m 3 , H =259.9m C =4.79MPa φ Substituting 35° into equation (3), the hole enlargement height is calculated. R b It is 0.5m.

[0026] The slurry diffusion radius R k The calculation formula is shown in equation (III): (III) In the formula: P This refers to the grouting pressure; b The width of the crack; τ The yield strength of the slurry; r 0 represents the radius of the outer borehole.

[0027] According to on-site measurements, the grouting pressure P The Pa value is 500, and the crack width is... b The slurry yield strength is 0.1 mm. τ The pressure is 1.2 Pa, and the radius of the borehole outside the alley is... r 0 is 37.5mm. (The remaining text appears to be incomplete and possibly contains errors.) P=500Pa, b =2.5mm τ =1.2Pa、 r Substituting 0 = 37.5 mm into equation (3), the slurry diffusion radius is calculated. R k It is 1079mm.

[0028] (2) Design the roof support method and spacing of the roadway; The top slab anchor bolts are designed as φ22×2800mm high-strength anchor bolts, with a row spacing of 800×800mm; the anchor cables are φ21.8×9000mm steel strand anchor cables, with a row spacing of 1300×1600mm, and the row spacing of all anchor cables is ≤2. R b .

[0029] (3) Construction of anchor cable drilling: Anchor cable drilling is carried out using an anchor cable drilling machine with a Φ27mm drill bit; (4) Enlarging the hole: Use an anchor cable drilling machine with a Φ75mm drill bit to enlarge the outer side of the anchor cable hole; See Figure 1 In one embodiment, the enlarged hole height 2 has a length of 500 mm.

[0030] (5) Anchoring: When installing anchor cable 1, a special mixing driver is installed at the lower end of anchor cable 1. The anchor cable 1 is used to push the anchoring agent into the borehole slowly to ensure that all the anchoring agent is delivered to the bottom of the hole. The hexagonal head at the tail of the special mixing driver is inserted into the anchor cable drilling machine and mixed while pushing it forward. (6) Install the sealing and grouting device: Install the sealing device 2, tray 3 and lock 4 in sequence at the tail of the anchor cable 1; See Figure 3 The sealing device 2 has an outer diameter of 73mm, an inner diameter of 22mm, and a length of 550mm, with a through anchor cable borehole 5 at its center. A tray 3 is provided on one side of the sealing device 2 along the direction of the anchor cable 1. The sealing device 2 has a bag 8 inside, which contains chemical material A 9 and chemical material B 10, respectively. Chemical material A 9 is Marisan A material, and chemical material B 10 is Marisan B material. A lock is provided on the side of the tray opposite the sealing device.

[0031] (7) Tensioning the anchor cable: The tensioning equipment is installed on the exposed section of the anchor cable 1. The anchor cable 1 is tensioned and pre-tightened by the tensioning equipment, so that the sealing device 2 is squeezed and broken by the surrounding rock. The material in the sealing device 2 is quickly mixed and pressed into the crack 7 of the surrounding rock in the roadway, and quickly hardens into a high-strength sealing material 13, thereby achieving the effect of effectively blocking water.

[0032] Although the present invention has been described in detail by way of preferred embodiments, the present invention is not limited thereto. Various equivalent modifications or substitutions can be made to the embodiments of the present invention by those skilled in the art without departing from the spirit and essence of the invention, and such modifications or substitutions should all be within the scope of the present invention. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should also be covered within the protection scope of the present invention.

Claims

1. A method for sealing anchor cable holes in a water-bearing roadway in the roof, characterized in that, Includes the following steps: (1) Calculate the borehole height and slurry diffusion radius based on the roadway cross-section; (2) Design the roof support method and spacing of the roadway; (3) Construction of anchor cable drilling: Anchor cable drilling is carried out using an anchor cable drilling machine with a Φ27mm drill bit; (4) Enlarging the hole: Use an anchor cable drilling machine with a Φ75mm drill bit to enlarge the outer side of the anchor cable hole; (5) Anchoring: When installing anchor cables, a special mixing driver is installed at the lower end of the anchor cable. The anchor cable is used to push the anchoring agent into the borehole slowly to ensure that all the anchoring agent is delivered to the bottom of the hole. The hexagonal head at the tail of the special mixing driver is inserted into the anchor cable drilling machine and mixed while pushing it forward. (6) Install the sealing and grouting device: Install the sealing device, tray and lock in sequence at the tail of the anchor cable; (7) Tensioning anchor cable: The tensioning equipment is installed on the exposed section of the anchor cable. The anchor cable is tensioned and pre-tightened by the tensioning equipment, so that the sealing device is squeezed and broken by the surrounding rock. The material in the sealing device is quickly mixed and pressed into the fracture zone of the surrounding rock in the roadway, and quickly hardens into a high-strength sealing material, thereby achieving the effect of effectively blocking water.

2. The method for sealing anchor cable holes in a water-bearing roadway as described in claim 1, characterized in that, In step (1), the formula for calculating the hole enlargement height is shown in equation (I): （I） Where: reduction factor N The formula for calculating 0 is shown in equation (II): (II) In the formula: Γ t For the timing of tunnel support, when the support time after excavation is less than 8 hours, Γ t Taking 1, when the support time after excavation is 8~16h, Γ t Taking 0.75, when the support time after excavation is 16~24h, Γ t Take 0.5, when the support time after excavation is greater than 24 hours, Γ t Take 0.25; Q c This is a coefficient representing the complexity of the geological structure of the tunnel area. When the geological structure is simple... Q c When the value is 0.25, and the geological structure is of medium quality, Q c When the geological structure is complex, a value of 0.5 is used. Q c When the value is 0.75, and the geological structure is extremely complex, Q c Take 1; R 0 represents the radius of the tunnel; γ Unit weight of the rock strata; H To deepen the tunnel; C The cohesion of the top strata; φ The internal friction angle of the top rock strata.

3. The method for sealing anchor cable holes in a water-bearing roadway as described in claim 1, characterized in that, The slurry diffusion radius R k The calculation formula is shown in equation (III): (III) In the formula: P The pressure of the slurry; b The width of the crack; τ The yield strength of the slurry; r 0 represents the radius of the outer borehole.

4. The method for sealing anchor cable holes in a water-bearing roadway as described in claim 1, characterized in that, The spacing between all anchor cables is ≤2. R b , R b This refers to the height of the enlarged hole.

5. A tunnel anchor cable hole sealing device for implementing the sealing method as described in claim 1, characterized in that, It includes an anchor cable and a sealing device fitted onto the anchor cable; the center of the sealing device is a through-hole in the anchor cable; a tray is provided on one side of the sealing device along the anchor cable direction; a bag is provided inside the sealing device, and the bag contains sealing material; a lock is provided on the side of the tray opposite the sealing device.

6. The tunnel anchor cable hole sealing device as described in claim 5, characterized in that, The sealing material includes chemical material A and chemical material B; chemical material A and chemical material B are mixed and then solidified to form a sealing material.

7. The tunnel anchor cable hole sealing device as described in claim 6, characterized in that, The sealing device has multiple partitions that divide it into multiple adjacent spaces, and chemical material A and chemical material B are placed in adjacent spaces.

8. The tunnel anchor cable hole sealing device as described in claim 5, characterized in that, The edges of the anchor cable boreholes are equipped with sealing strips.

9. The tunnel anchor cable hole sealing device as described in claim 5, characterized in that, The sealing device has an outer diameter of 73mm, an inner diameter of 22mm, and a length of [missing information]. R b +50 mm, R b This refers to the height of the enlarged hole.

10. The tunnel anchor cable hole sealing device as described in claim 6, characterized in that, Chemical material A is Marisan A material, and chemical material B is Marisan B material.

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