A method for treating floor heave in roadways with fractured rock floor

Abstract

This invention discloses a method for treating floor heave in roadways with fractured soft rock floors, relating to the field of roadway floor heave treatment technology. The method includes: firstly, drilling holes on both sides of the roadway floor; applying pressure to the surrounding rock around the borehole walls using a pressurizing device to laterally compact the borehole walls; constructing prestressed concrete piles in the pressurized and expanded boreholes; installing steel pipes, composed of several threaded sections, into the boreholes; placing anchor cables within the installed steel pipes; grouting concrete into the steel pipes; and applying pre-tightening force to the anchor cables to form prestressed concrete piles; grouting the gap between the prestressed concrete piles and the boreholes, forming an integral structure with the prestressed concrete piles; and finally, pouring waterproof concrete onto the roadway floor to seal seepage channels. This invention, by combining mechanical pressurization with grouting and anchoring systems, can ensure the stability and load-bearing capacity of soft rock floors during long-term operation.

Description

Technical Field

[0001] This invention relates to the field of roadway floor heave treatment technology, specifically to a method for treating floor heave in roadways with soft rock fractured floor. Background Technology

[0002] In deep, high-pressure roadways, floor heave is a frequent occurrence. Severe floor heave can lead to roadway deformation and instability, equipment damage and transportation difficulties, increased risk of flooding and inundation, support system failure, reduced traffic flow and work efficiency, and increased maintenance costs. Consequently, mines invest significant manpower and resources in "repairing" the heave. If floor heave is not effectively controlled and managed, it can even lead to complete roadway instability and collapse, ultimately resulting in the abandonment of the entire mining area. Therefore, the structure and methods for managing floor heave are a crucial technical means to effectively improve the safety and stability of roadways.

[0003] Mechanical compaction devices in coal mine roadways are primarily used to reinforce the roadway floor to prevent floor heave and rock deformation. Commonly used mechanical compaction equipment includes hydraulic jacks, floor support devices, anchoring systems, and vibratory compaction equipment. Hydraulic jacks use the high-pressure thrust generated by the hydraulic system to locally compact soft rock layers, while floor support devices provide uniform pressure over large areas. Anchoring systems connect the floor to the surrounding rock mass using anchor bolts, enhancing overall stability. Vibratory compaction equipment compacts soft rock layers through vibration, making it particularly suitable for large-area floor compactions.

[0004] The advantages of mechanical pressurization devices are their ability to rapidly increase the density of the base plate, prevent bulging, and offer high flexibility. However, mechanical pressurization also has limitations, such as uneven pressurization potentially leading to localized deformation, and higher equipment procurement and maintenance costs. Although mechanical pressurization can significantly improve base plate stability in the short term, it cannot guarantee the stability and load-bearing capacity of soft rock base plates during long-term operation.

[0005] Therefore, existing technologies need further improvement. However, for long-term reinforcement, it is often necessary to combine other methods, such as grouting and anchoring systems, to ensure the stability and load-bearing capacity of soft rock base plates during long-term operation. Summary of the Invention

[0006] The purpose of this invention is to provide a method for treating floor heave in roadways with fractured soft rock floor slabs. This method combines mechanical pressurization with grouting and anchoring systems to ensure the stability and load-bearing capacity of the soft rock floor slab during long-term operation.

[0007] To achieve the above objectives, the present invention adopts the following technical solution: a method for treating floor heave in roadways with fractured soft rock floors, comprising the following steps: Step 1, drilling holes on both sides of the roadway floor; Step 2, applying pressure to the surrounding rock around the borehole wall using a pressurizing device to laterally compact the borehole wall; the pressurizing device includes an operating lever, a hydraulic pump, a cylinder, an inlet pipe, an outlet pipe, a hydraulic control valve, a reset bolt, a cylinder body, a plunger, a pressurizing column, a pressurizing arm, and a housing; the operating lever is connected to the cylinder, and the hydraulic pump is used to pressurize the cylinder. Manual pressurization is performed; the oil cylinders are respectively connected to an oil inlet pipe and an oil outlet pipe. The oil inlet pipe is connected to a hydraulic control valve. The lower part of the hydraulic control valve is connected to a plunger. The hydraulic control valve controls the pressurization of the plunger, so that hydraulic oil enters the plunger. The plunger and the pressurizing column are connected by a piston. The lower part of the piston is connected to the pressurizing column. The pressurizing column includes a housing, a pressurizing arm and a telescopic rod. Oil is injected into the housing to form a pressurizing column oil chamber. The plunger pushes the piston to pressurize the hydraulic oil in the pressurizing column oil chamber.

[0008] The cylinder body is located on the outside of the hydraulic control valve; the reset bolt is installed on the cylinder body; a hole is provided on the side wall of the outer shell, the hole is connected to a telescopic rod, the telescopic rod can extend and retract in parallel under pressure, the telescopic rod is connected to a pressure arm, when the telescopic rod extends, it drives the pressure arm to move horizontally outward to apply pressure to the borehole wall.

[0009] Step 3: For the prestressed concrete piles constructed by drilling after pressure expansion, install steel pipes into the borehole. The steel pipes are composed of several threaded sections. Place anchor cables in the installed steel pipes. After grouting concrete into the steel pipes, apply pre-tightening force to the anchor cables to form a prestressed concrete pile.

[0010] Step 4: Grouting is performed in the gap between the prestressed concrete pile and the borehole, and the grouting area forms an integral structure with the prestressed concrete pile.

[0011] Step 5: Pour waterproof concrete into the tunnel floor slab to seal the seepage channels.

[0012] In the above-mentioned method for treating floor heave in a roadway with a fractured rock floor, in step one, the extent of the fractured rock zone on the roadway floor is first determined, and then holes are drilled on both sides of the roadway floor; the drilling depth reaches the fractured rock zone on the roadway floor.

[0013] The above-mentioned method for treating floor heave in a soft rock fractured floor roadway includes a pressure column consisting of several sections, with adjacent pressure columns connected by threads, and each pressure column section being 1m long.

[0014] The above-mentioned method for treating floor heave in roadways with fractured soft rock floor involves evenly spaced four sets of holes on the sidewalls of the outer shell, with three holes in each set vertically, and each hole corresponding to a telescopic rod.

[0015] The above-mentioned method for treating floor heave in a soft rock fractured floor roadway includes a pressure display dial on the pipeline connecting the hydraulic pump and the oil cylinder. The oil outlet pipe is connected to the cylinder body. The hydraulic oil entering the plunger flows into the cylinder body by opening the reset bolt and returns to the oil cylinder through the return oil pipe.

[0016] Compared with the prior art, the present invention brings the following beneficial technical effects: (1) The present invention drills holes on both sides of the roadway floor, the drilling depth reaches the fracture zone of the floor rock strata, and uses a pressurizing device to apply pressure to the borehole wall laterally. Lateral compaction of the borehole can effectively seal the cracks and pores in the rock mass and improve the density of the rock mass. This compaction effect can enhance the overall bearing capacity of the rock mass and reduce the subsidence and deformation of the floor.

[0017] (2) The present invention can improve the stability of the borehole wall, reduce water inflow, improve construction safety, optimize drilling efficiency, reduce construction costs and enhance soil bearing capacity by designing a pressurization device.

[0018] (3) The pressurizing device designed in this invention can be effectively extended by threads to reach the depth of the bottom plate crushing zone.

[0019] (4) After the borehole is compacted, the cracks and pores of the bottom plate will be significantly reduced, the permeability coefficient will decrease, thereby preventing the infiltration and erosion of groundwater. Then, the borehole is supported by constructing prestressed concrete piles in the borehole.

[0020] (5) Grouting will further fill the remaining cracks. After the grout solidifies, it forms a solid filling material, which further improves the water resistance and stability of the base plate. The grouting area and the prestressed concrete pile form a whole, which can distribute the load borne by the prestressed concrete pile more evenly, reduce the stress concentration at the bottom or around the pile, and reduce the risk of pile failure. Attached Figure Description

[0021] Figure 1 This is a schematic diagram showing the expansion of the boreholes on both sides of the tunnel floor slab according to the present invention.

[0022] Figure 2 This is a top view of the borehole wall in the tunnel floor of the present invention.

[0023] Figure 3 This is a schematic diagram of prestressed concrete grouting for the tunnel floor slab.

[0024] Figure 4 This is a top view of the tunnel floor slab under construction.

[0025] Figure 5 This is a schematic diagram of the pressurization device of the present invention.

[0026] Figure 6 This is a top view of the pressure column of the present invention.

[0027] Figure 7 This is a partial schematic diagram of the pressure column of the present invention.

[0028] In the diagram: 1-Space inside the tunnel; 2-Floor plate; 3-Crack; 4-Borehole; 5-Borehole expansion area; 6-Grouting port; 7-Grouting plug; 8-Plate; 9-Anchor cable; 10-Grouting area of ​​prestressed concrete pile; 11-Steel pipe; 12-Grouting area outside prestressed concrete pile; 13-Hydraulic pump; 14-First pressure display dial; 15-Operating lever; 16-Pressure control valve; 17-Hydraulic cylinder; 18-Inlet control valve; 19-Inlet pipe; 20-Suction port; 21-Outlet control valve ; 22-Outlet pipe; 23-Outlet port; 24-Outlet port; 25-Plunger; 26-Cylinder body; 27-Hydraulic control valve; 28-Second pressure display dial; 29-Pressure sensing device; 30-Reset bolt; 31-Threaded connection between the pressurizing column housing and the pressurizing column; 32-Piston; 33-Oil chamber of the pressurizing column; 34-Pressure arm; 35-Housing; 36-Telescopic rod; 37-Lower piston of the pressurizing column connector; 38-Lower switch of the pressurizing column; 39-Threaded connection at the lower end of the pressurizing column connector; 40-Pressure chamber. Detailed Implementation

[0029] This invention proposes a method for treating floor heave in roadways with fractured soft rock floors. To make the advantages and technical solutions of this invention clearer and more explicit, the invention will be further described below with reference to specific embodiments.

[0030] It is understood that the connection relationships described in this application refer to direct or indirect connections. For example, the connection between A and B can be a direct connection between A and B, or an indirect connection between A and B through one or more other electrical components. For example, A can be directly connected to C, and C can be directly connected to B, thus achieving a connection between A and B through C. It is also understood that the "A connects to B" described in this application can be a direct connection between A and B, or an indirect connection between A and B through one or more other electrical components.

[0031] The main technical concept of this invention is as follows: By drilling holes 4 on both sides of the tunnel floor slab 2 and using a pressurizing device to laterally pressurize the holes 4, a deep-level improvement effect can be achieved on the soft rock fracture floor slab, thereby improving the density and mechanical properties of the floor slab 2. Then, prestressed concrete piles are constructed in the pressurized and expanded holes 4. Grouting further fills the remaining cracks 3, and the grouting area and the prestressed concrete piles form a whole, thereby improving the overall stability of the floor slab 2. This effectively reinforces the fractured or loose rock strata of the floor slab 2, reduces the floor heave velocity, and controls the occurrence of tunnel floor heave.

[0032] like Figure 1 As shown in the schematic diagram of a soft rock fractured floor roadway, the diagram illustrates the roadway's internal space 1, floor 2, fissure 3, borehole 4, and borehole expansion zone 5. Combined with... Figure 2 and Figure 3 As shown in the figure, the grouting port 6, the grout stop plug 7, the tray 8, the anchor cable 9, the grouting area of ​​the prestressed concrete pile 10, the steel pipe 11, and the external grouting area of ​​the prestressed concrete pile 12 are shown.

[0033] Combination Figures 1 to 4 As shown, the method for treating floor heave in roadways with fractured soft rock floors includes the following steps: Step 1: Widen and resurface the roadway where floor heave has occurred, restoring it to the relevant cross-sectional dimensions, and provide temporary support. Drill holes 4 at 10m intervals in the floor slab 2 of the heave area, reaching the stable rock strata below. Examine these holes to determine the extent of the fractured rock zone in floor slab 2, providing a reference for the depth of the drill holes 4.

[0034] Step 2: Drill holes on both sides of the tunnel floor 2 using drilling equipment. The diameter of the holes is 89mm and the depth is the same as the depth of the holes obtained in Step 1, ensuring that the depth of the holes reaches the range of the rock fracture zone of the floor 2.

[0035] Step 3: Apply pressure to the weak surrounding rock around borehole 4 using a pressurizing device. This can effectively seal the fissures and pores in the rock mass and increase the density of the rock mass.

[0036] To achieve lateral pressurization of the borehole wall in borehole 4, the existing pressurization device is not well-matched with borehole 4. This invention designs a pressurization device, the specific structure of which is as follows: Figure 5As shown, the pressurizing device includes a hydraulic pump 13, a first pressure display dial 14, an operating lever 15, a pressurization / unpressurization control valve 16, a cylinder 17, an oil inlet control valve 18, an oil inlet pipe 19, a suction port 20, an oil outlet control valve 21, an oil outlet pipe 22, an outlet port 23, an oil outlet 24, a plunger 25, a cylinder body 26, a hydraulic control circuit 27, a second pressure display dial 28, a pressure sensing device 29, a reset bolt 30, a pressurizing column housing connection thread 31, a piston 32, a pressurizing column oil chamber 33, a pressurizing arm 34, a housing 35, a telescopic rod 36, a lower end piston of the pressurizing column connection 37, a lower end switch of the pressurizing column 38, a lower end thread of the pressurizing column connector 39, and a pressurizing chamber 40. The hydraulic pump 13 is a manual hydraulic pump connected to the cylinder 17. The manual hydraulic pump pressurizes the cylinder 17. The operating lever 15 facilitates operation. A first pressure display dial 14 is installed on the pipeline connecting the hydraulic pump 13 and the cylinder 17 for easy pressure monitoring. The inlet pipe 19 and outlet pipe 22 are connected to the cylinder 17. The cylinder 17 contains two-thirds of its volume of hydraulic oil. The hydraulic oil enters the pressurization chamber 40 connected to the inlet pipe 19 through the inlet pipe 19 and the suction port 20. The lower part of the hydraulic control circuit 27 in the pressurization chamber 40 is connected to the plunger 25. The hydraulic control circuit 27 controls the pressurization of the plunger 25, allowing hydraulic oil to enter. The top of the plunger 25 is equipped with a plunger connection pressurization thread 31, and the lower part of the piston 32 is connected to the pressurization column. A cylinder body 26 is located outside the hydraulic control circuit 27; a reset bolt 30 is installed on the cylinder body 26. A pressure sensing device 29 is installed inside the hydraulic control valve 27, and the measured pressure is displayed on the second pressure display dial 28.

[0037] Specifically, when the hydraulic pump 13 pressurizes the cylinder 17, it opens the oil outlet control valve 21 and the suction port 20, allowing hydraulic oil to enter the pressurizing chamber 40 through the oil inlet pipe 19. The pressurization is continuously monitored until the first pressure display dials 14 and 28 reach the predetermined pressure. The hydraulic oil in the pressurizing column is separate and not interconnected with the hydraulic oil in the cylinder 17. The plunger 25 continuously extends and contacts the piston 32, squeezing the hydraulic oil in the pressurizing column, thereby increasing the hydraulic pressure within the pressurizing column. After completing the work, the hydraulic pump 13 depressurizes through the pressure relief control valve 16. The pressurizing chamber 40 opens the reset bolt 30, allowing the hydraulic oil in the pressurizing chamber 40 to enter the return pipe through the opening of the discharge port 23 and the oil outlet control valve 21, ultimately returning to the cylinder 17, and retracting the plunger 25 to its initial position. The oil outlet 24 is designed to prevent the plunger 25 from extending too far. Hydraulic oil flows out through the oil outlet 24 on the cylinder body 26 to achieve the purpose of pressure relief.

[0038] The hydraulic oil inside the pressure column is pressurized by piston 32, thereby applying lateral pressure to the sidewall of borehole 4. Specifically, the structure of the pressure column is combined with... Figure 6 , Figure 7 As shown, the pressure column includes a housing 35, a pressure arm 34, and a telescopic rod 36. Oil is injected into the housing 35 to form a pressure column oil chamber 33. The piston 32 is pushed by the plunger 25 to pressurize the hydraulic oil in the pressure column oil chamber 33. A hole communicating with the interior of the housing 35 is provided on the side wall of the housing 35. The hole is connected to the telescopic rod 36. The telescopic rod 36 can extend and retract in parallel under pressure. The telescopic rod 36 is connected to the pressure arm 34. When the telescopic rod 36 extends, it drives the pressure arm 34 to move horizontally outward to apply pressure to the borehole wall 4. The telescopic rod 36 extends outward under pressure and retracts inward when the pressure decreases. Therefore, by pressurizing, the telescopic rod 36 extends outward, thereby pushing the pressure arm 34 to apply lateral pressure to the borehole 4.

[0039] The pressure column of this invention is a segmented design, and is actually assembled on-site according to the depth of borehole 4. Each segment of the pressure column is 1m long. Considering that it can be easily placed in the tunnel, the length of the pressure column should not be too long. In actual use, adjacent pressure columns are connected and installed through the connecting thread 31 of the pressure column shell and the thread 39 at the lower end of the pressure column connector. The pressure columns are pressurized by opening the switch 38 at the lower end of the pressure column and extending the piston 37 at the lower end of the pressure column.

[0040] Preferably, the pressure column and the plunger 25 are connected by a pressure column housing connecting thread 31, which is equivalent to the pressure column housing connecting thread 31 serving as an external thread to connect the pressure column and the plunger 25.

[0041] Step 4: Construct prestressed concrete piles in the expanded borehole 4. Place steel pipe 11 in borehole 4, connect and assemble steel pipe 11 with thread 30, place anchor cable 9 in steel pipe 11, and inject grout into steel pipe 11. After grouting, install grout stop plug 7 and tray 8. After concrete grouting of steel pipe 11, apply pre-tightening force to anchor cable 9 to form prestressed concrete pile. Prestressed concrete pile is superior to ordinary concrete pile in terms of bearing capacity, deformation resistance, and self-strength, and can effectively prevent deformation of base plate 2.

[0042] Step 5: Grouting is performed in the gap between the prestressed concrete pile and borehole 4 to fill the remaining voids and cracks 3 after compaction, thereby further improving the integrity and density of the rock strata.

[0043] Step 6: Pour waterproof concrete into the tunnel floor slab 2 to seal the seepage channels and enhance the strength of the floor slab 2.

[0044] The hydraulic control valve 27, pressure arm 34, telescopic rod 36 and other structures mentioned in this invention can be implemented by those skilled in the art by referring to existing technologies.

[0045] It should be noted that those skilled in the art should recognize that the above embodiments are only used to illustrate this application and are not intended to limit this application. Any appropriate changes and variations made to the above embodiments within the essential spirit and scope of this application fall within the scope of protection claimed by this application.

Claims

1. A method for treating floor heave in a soft rock fractured floor roadway, characterized in that, Comprise the following steps in turn: Step one, drilling on both sides of the roadway floor; Step two, using a pressure device to apply pressure to the surrounding rock around the borehole wall, and compacting the borehole wall laterally; the pressure device comprises an operating rod, a hydraulic pump, an oil cylinder, an oil inlet pipe, an oil outlet pipe, a hydraulic control valve, a reset bolt, a cylinder body, a plunger, a pressure column and a pressure arm, the operating rod is connected with the oil cylinder, the hydraulic pump adopts a manual pressure mode; the oil cylinder is respectively connected with the oil inlet pipe and the oil outlet pipe, the oil inlet pipe is connected to the hydraulic control valve, the lower part of the hydraulic control valve is connected with the plunger, the plunger is pressurized by the hydraulic control valve, so that the hydraulic oil enters the plunger, the plunger is connected with the pressure column through a piston, the lower part of the piston is connected with the pressure column, the pressure column comprises an outer shell, a pressure arm and a telescopic rod, oil is injected into the outer shell to form a pressure column oil cavity, and the hydraulic oil in the pressure column oil cavity is pressurized by the piston pushed by the plunger; The outer side of the hydraulic control valve is provided with the cylinder body; the reset bolt is installed on the cylinder body; a hole is arranged on the side wall of the outer shell, the hole is connected with the telescopic rod, the telescopic rod can be parallelly telescoped in the pressurized state, the telescopic rod is connected with the pressure arm, and when the telescopic rod is elongated, the pressure arm is driven to move outward horizontally to apply pressure to the borehole wall; Step three, constructing a prestressed concrete pile on the pressurized and expanded borehole, installing a steel pipe in the borehole, the steel pipe is composed of a plurality of segments connected by threads, placing an anchor cable in the installed steel pipe, and applying a pre-tightening force to the anchor cable after grouting concrete in the steel pipe to form a prestressed concrete pile; Step four, grouting in the gap between the prestressed concrete pile and the borehole, and forming a whole structure with the grouting area and the prestressed concrete pile; Step five, pouring waterproof concrete on the roadway floor to close the water seepage channel.

2. The method for treating floor heave in a soft rock caving roadway according to claim 1, characterized in that: In step one, the range of the roadway floor rock fracture zone is determined first, and then drilling is performed on both sides of the roadway floor; the drilling depth reaches the roadway floor rock fracture zone.

3. The method for treating floor heave in a soft rock caving roadway according to claim 1, characterized in that: The pressure column is provided with a plurality of segments, adjacent pressure columns are connected by threads, and the length of each pressure column is 1m.

4. The method for treating floor heave in a soft rock caving gateway according to claim 1, characterized in that: Four groups of holes are arranged on the side wall of the outer shell in four directions, each group is vertically provided with three holes, and each hole is provided with a telescopic rod.

5. The method for treating floor heave in a soft rock caving gateway according to claim 1, characterized in that: A pressure display dial is arranged on the pipeline connecting the hydraulic pump and the oil cylinder, the oil outlet pipe is connected with the plunger, and the hydraulic oil in the plunger flows back to the oil cylinder through a backflow pipe.

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