Construction treatment method aiming at floor heave problem of mine roadway bottom plate

Abstract

The invention relates to the technical field of roadway bottom plate heaving floor reinforcing and supporting, in particular to a construction treatment method for solving the mine roadway bottom plate heaving floor problem. The hollow steel pipe pile is applied to treatment of the sliding type floor heave, the hollow steel pipe pile and the grouting slurry are combined to form the steel pipe concrete pile, the sliding type floor heave is treated to a great extent by means of the excellent property of the steel pipe concrete pile, meanwhile, the concrete prestressed hardened layer is laid on the broken bottom plate, and a foundation is provided for installation of the hollow steel pipe pile; the problems of hole collapse, sinking and the like in the drilling process are prevented; in order to reduce the influence of water on the broken bottom plate as much as possible, a waterproof hardened layer is laid on the concrete prestressed hardened layer, and the stability of the broken bottom plate is further protected; and finally, a matched construction scheme is provided for treatment of the sliding type floor heave, and compared with a related floor heave treatment technology, the problem of sliding type floor heave of the broken bottom plate can be effectively solved, and long-term stability of the broken bottom plate is kept.

Description

Technical Field

[0001] The invention relates to the technical field of tunnel floor floor heave reinforcement and support, and in particular to a construction treatment method for the problem of mine tunnel floor heave. Background Art

[0002] Coal mines are the ballast of our industrial energy production. How to ensure their efficient and safe production is particularly important. As coal mines enter deep mining, floor drum becomes the most common phenomenon of tunnel deformation during mining, which seriously affects the safety of life and property of coal mine enterprise personnel and hinders the efficient production of mines. In summary, how to effectively control the ability of tunnels to resist sliding deformation and reduce the problem of floor drum in tunnels based on existing support conditions has become a major issue that needs to be solved in this technical field. Summary of the invention

[0003] The purpose of the present invention is to provide a construction treatment method for the bottom bulge problem of mine tunnel floor.

[0004] The object of the present invention is achieved by the following means: a construction treatment method for the bottom bulge problem of the mine tunnel floor, the construction steps are as follows: Q1. Clean the crushing bottom plate: clean the loose crushing bottom drum in the crushing bottom plate, restore the original cross-sectional dimensions of the tunnel space, and keep the crushing bottom plate flat; Q2. Laying concrete prestressed hardened layer: Laying concrete prestressed hardened layer with concrete on the crushing bottom plate; Q3. Drilling holes for steel tube concrete piles: Use mining drilling equipment to drill holes for steel tube concrete piles on the prestressed concrete hardened layer. The holes for steel tube concrete piles need to pass through the prestressed concrete hardened layer and the broken bottom plate, and finally stabilize in the stable rock layer of the bottom plate; Q4. Install hollow steel pipe piles: insert the bottom of the hollow steel pipe pile into the stable rock layer of the bottom plate along the steel pipe concrete pile drilling hole, inject anchoring liquid into the steel pipe concrete pile drill for the initial fixation of the bottom of the hollow steel pipe pile and the stable rock layer of the bottom plate, and reserve the top of the hollow steel pipe pile outside the steel pipe concrete pile drilling hole; Q5. Grouting: Grouting is carried out through hollow steel pipe piles into the broken bottom plate. While the grouting slurry fills the hollow steel pipe piles and combines to form high-strength steel pipe concrete piles, it penetrates and seals the cracks in the surrounding rock of the bottom plate under high pressure; Q6. Pre-tightened steel tube concrete piles: lay anchor nets flat on the prestressed concrete hardening layer, pass the hollow steel tube piles through the center of the anchor nets, set square trays on the anchor nets, and pre-tighten the hollow steel tube piles and the square trays on the prestressed concrete hardening layer through locks; Q7. Laying the waterproof hardened layer: Lay the waterproof hardened layer on the prestressed concrete hardened layer, bury the hollow steel pipe piles, square trays and locks in the waterproof hardened layer, and the construction process is completed after the waterproof hardened layer is hardened and fixed.

[0005] As a further limitation, in Q3, the drilling depth of the CFST pile is based on the depth of the plastic zone of the roadway floor R P Set up; According to the superposition principle of elastic-plastic theory, when the lateral pressure coefficient λ≠1 of deep soft rock tunnel, the surrounding rock stress field is composed of the superposition of original rock stress and deviatoric stress; Assuming that the tunnel surrounding rock is isotropic and in an elastic stress state, the stress calculation formula is as follows:

[0006] The calculation formula for the equivalent radius of the roadway is: The radius formula of the surrounding rock plastic zone is obtained by using the stress formula and the equivalent radius formula as follows:

[0007] Where, P0-rock formation self-weight stress; R0-tunnel equivalent radius; R1-tunnel radius; σ θ - tangential stress; σ r - radial stress; R p -Radius of plastic zone; C-cohesion; φ-internal friction angle of rock; h-tunnel height; P1-support resistance; λ-lateral pressure coefficient; θ-polar angle, since λ>1, the polar angle is 90°.

[0008] As a further limitation, in Q3, the spacing between the steel tube concrete pile boreholes 4 is selected between 800-2000 mm according to an empirical formula combined with the site.

[0009] The present invention discloses a construction treatment method for the bottom drum problem of mine tunnel floor. The innovation of the present invention lies in: applying hollow steel pipe piles to the treatment of sliding type bottom drum, combining the hollow steel pipe piles with grouting slurry to form steel pipe concrete piles, utilizing the excellent properties of the steel pipe concrete piles to treat the sliding type bottom drum to a great extent, and at the same time laying a concrete prestressed hardened layer on the crushing bottom plate to provide a basis for the installation of the hollow steel pipe piles and prevent problems such as hole collapse and sinking during drilling; in order to minimize the influence of water on the crushing bottom plate, laying a water-proof hardened layer on the concrete prestressed hardened layer to further protect the stability of the crushing bottom plate; finally, a matching construction plan is proposed for the treatment of sliding type bottom drum. Compared with the relevant bottom drum treatment technology, the problem of sliding type bottom drum of the crushing bottom plate can be effectively solved, and the long-term stability of the crushing bottom plate can be maintained.

[0010] Comparison between traditional method and the method of the present invention: Comparison Items Traditional methods Method of the present invention Similar model surrounding rock deformation The maximum deformation of the tunnel surrounding rock is 20mm for the top plate, 23mm for the two sides and 30.2mm for the bottom plate. The maximum deformation of the tunnel surrounding rock is 8.8mm for the top plate, 7mm for the two sides and 12mm for the bottom plate. Lane floor repair frequency Regular repairs every 3 months or half a year, high repair costs Basically no need for repair, or only partial maintenance, saving costs Conditions of Use The bottom plate surrounding rock strength is required to be high and the whole is intact. Applicable to complex floor conditions and broken floor surrounding rock In similar simulation tests, the maximum settlement of the roof of the steel tube concrete pile-supported tunnel was 8.8mm, the maximum convergence of the two sides was 7mm, and the maximum bulging of the bottom plate was 12mm. Compared with the traditional method, the settlement of the tunnel roof was reduced by 56%, the convergence of the two sides was reduced by 69.5%, and the bulging of the bottom plate was reduced by 60%, and the deformation of the surrounding rock was effectively controlled. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] The present invention is further described in detail below in conjunction with the accompanying drawings: Figure 1 It is a schematic diagram of a construction treatment method for the bottom bulge problem of a mine tunnel floor according to the present invention; Figure 2 It is a schematic diagram of the steel tube concrete pile structure of the present invention Figure 3 Is a schematic diagram of the tunnel space of the present invention; Figure 4 Is a schematic diagram of the structure of the prestressed concrete hardened layer of the present invention; Figure 5 This is a schematic diagram of the structure of the steel tube concrete pile drilling of the present invention; Figure 6 This is a schematic diagram of the structure of the steel tube concrete pile and the steel tube concrete pile drilled connection of the present invention; Figure 7 This is a schematic diagram of the structure of the steel tube concrete pile and the prestressed concrete hardened layer connected to the present invention; Figure 8 It is a flow chart of the construction method of the tunnel sliding type floor anti-bottom heave support structure of the present invention; Fig. 9 for Figure 1 A partial enlarged view of; In the figure, 1. hollow steel pipe pile; 2. square pallet; 3. grouting slurry; 4. steel pipe concrete pile drilling; 5. tunnel space; 6. anchor net; 7. lock; 8. concrete prestressed hardened layer; 9. water-proof hardened layer; 10. crack; 11. crushing bottom plate; 12. loose crushing bottom drum. DETAILED DESCRIPTION

[0012] like Figure 8 As shown, a construction method of a tunnel sliding type floor anti-bottom heave support structure of the present invention comprises the following steps: Q1. Cleaning the crushing bottom plate: To ensure the normal progress of the tunnel construction, first clean the loose crushing bottom drum 12 area in the crushing bottom plate 11, restore the original cross-sectional dimensions of the tunnel space 5, and keep the crushing bottom plate 11 flat.

[0013] Q2. Laying the prestressed concrete hardening layer 8: After the original size of the tunnel space 5 is restored, the prestressed concrete hardening layer 8 is laid on the crushing bottom plate 11 with concrete of designed proportion. After the prestressed concrete hardening layer 8 reaches the expected strength, the next step of construction can be carried out.

[0014] Q3. Drilling steel tube concrete pile borehole 4: When the prestressed concrete hardened layer 8 reaches the expected strength, the steel tube concrete pile borehole 4 is drilled on the prestressed concrete hardened layer 8 using mining drilling equipment according to the construction plan. The spacing and drilling depth of the steel tube concrete pile borehole 4 are constructed according to the designed depth. The steel tube concrete pile borehole 4 needs to pass through the prestressed concrete hardened layer 8 and the broken bottom plate 11, and finally stabilize in the stable rock layer of the bottom plate.

[0015] In Q3, the drilling depth of the steel tube concrete pile is based on the depth of the plastic zone of the tunnel floor R P Set up; According to the superposition principle of elastic-plastic theory, when the lateral pressure coefficient λ≠1 of deep soft rock tunnel, the surrounding rock stress field is composed of the superposition of original rock stress and deviatoric stress; Assuming that the tunnel surrounding rock is isotropic and in an elastic stress state, the stress calculation formula is as follows:

[0016] The calculation formula for the equivalent radius of the roadway is: The radius formula of the surrounding rock plastic zone is obtained by using the stress formula and the equivalent radius formula as follows:

[0017] Where, P0-rock formation self-weight stress; R0-tunnel equivalent radius; R1-tunnel radius; σ θ - tangential stress; σ r - radial stress; R p -Radius of plastic zone; C-cohesion; φ-internal friction angle of rock; h-tunnel height; P1-support resistance; λ-lateral pressure coefficient; θ-polar angle, since λ>1, the polar angle is 90°.

[0018] As a further limitation, in Q3, the spacing between the steel tube concrete pile boreholes 4 is selected between 800-2000 mm according to an empirical formula combined with the site.

[0019] Q4. Install the hollow steel pipe pile 1: insert the bottom end of the hollow steel pipe pile 1 into the stable rock layer of the bottom plate along the steel pipe concrete pile drilling hole 4, and inject anchoring liquid into the steel pipe concrete pile drilling hole 4 appropriately to facilitate the initial fixation of the bottom end of the hollow steel pipe pile 1 and the stable rock layer of the bottom plate, while the top part of the hollow steel pipe pile 1 is reserved outside the steel pipe concrete pile drilling hole 4 to facilitate subsequent anchoring.

[0020] Q5. Grouting: After the installation of the hollow steel pipe pile 1 is completed, grouting is carried out toward the broken bottom plate 11 through the hollow steel pipe pile 1. The grouting slurry 3 is combined with the hollow steel pipe pile 1 to form a high-strength steel pipe concrete pile. At the same time, the grouting slurry 3 penetrates into the bottom plate surrounding rock cracks 10 under the action of high pressure, sealing the bottom plate surrounding rock cracks 10 and improving the surrounding rock strength.

[0021] Q6. Install the anchor net 6 and pre-tighten the steel tube concrete pile: lay the anchor net 6 on the prestressed concrete hardened layer 8, and the center of the anchor net 6 passes through the hollow steel tube pile 1. At the same time, ensure the flatness of the anchor net 6 during the laying process; after the anchor net 6 is laid, pre-tighten the top of the steel tube concrete pile through the square tray 2 and the lock 7, and the bottom end of the square tray 2 is crimped onto the anchor net 6 to press the anchor net 6 onto the prestressed concrete hardened layer 8. Pre-tighten the hollow steel tube pile 1 and the square tray 2 on the prestressed concrete hardened layer 8 through the lock 7. Because the anchor net 6 effectively disperses the pre-tightening force at the bottom of the square tray 2, the pre-stressed concrete hardened layer 8 is prevented from being fractured by the square tray 2 during the pre-tightening of the steel tube concrete pile.

[0022] Q7. Laying water-proof hardened layer 9: Lay water-proof hardened layer 9 on the concrete prestressed hardened layer 8, cover the hollow steel pipe pile 1, square tray 2 and lock 7 in the water-proof hardened layer 9 to prevent water from affecting the surrounding rock and steel pipe concrete piles of the crushing bottom plate 11. After the water-proof hardened layer 9 is hardened and fixed, the construction process is basically completed. Laying water-proof hardened layer 9 can further strengthen the bottom plate and prevent water from contacting the bottom plate, reducing the impact of water on the crushing bottom plate 11.

[0023] Figure 1 , Fig. 9As shown in the figure, a tunnel sliding type bottom plate anti-bottom drum support structure is obtained by adopting the above construction treatment method. Among them, the hollow steel pipe pile 1 and the grouting slurry 3 form a steel pipe concrete pile support structure with good mechanical properties. After the loose broken surrounding rock of the tunnel bottom plate is cleaned, the concrete prestressed hardened layer 8 is laid on the broken bottom plate 11, and the steel pipe concrete pile borehole 4 is drilled on the concrete prestressed hardened layer 8. The steel pipe concrete pile borehole 4 passes through the concrete prestressed hardened layer 8 and extends to the stable area of ​​the broken bottom plate 11. The hollow steel pipe pile 1 is inserted into the steel pipe concrete pile borehole 4, one section is connected to the concrete prestressed hardened layer 8, and the other section is connected to the stable area of ​​the broken bottom plate 11. The concrete prestressed hardened layer 8 is connected to the stable area of ​​the broken bottom plate 11. The prestressed hardened layer 8 is a prerequisite for the hollow steel pipe pile 1 and the steel pipe concrete pile drilling 4. After the steel pipe concrete pile drilling hole 4 is drilled in the prestressed concrete hardened layer 8, grouting is performed into the surrounding rock of the crushed bottom plate 11 through the hollow steel pipe pile 1. While the grouting slurry 3 forms a steel pipe concrete pile with the hollow steel pipe pile 1, the grouting slurry 3 diffuses through the hollow steel pipe pile 1 to fill the cracks 10 in the bottom plate surrounding rock, thereby strengthening the bottom plate surrounding rock. In order to prevent the hydrolysis of the surrounding rock of the crushed bottom plate 11 by air water and seepage water, a waterproof hardened layer 9 is laid on the prestressed concrete hardened layer 8 to further strengthen the protection of the surrounding rock of the crushed bottom plate 11.

[0024] When supporting the tunnel space 5 during the on-site application, if there is no obviously loose crushing bottom drum 12 on the crushing bottom plate 11, the prestressed concrete hardened layer 8 can be directly laid on the crushing bottom plate 11 to consolidate the surface surrounding rock of the crushing bottom plate 11, preliminarily prevent the influence of water on the crushing bottom plate 11, provide conditions for the installation of the hollow steel pipe pile 1 and the steel pipe concrete pile drilling 4, and prevent the occurrence of hole collapse and collapse during the drilling process; then select a suitable span to drill the steel pipe concrete pile drilling 4 on the prestressed concrete hardened layer 8, the steel pipe concrete pile drilling 4 extends from the prestressed concrete hardened layer 8 to the crushing bottom plate 11 surrounding rock stabilization layer, the top of the hollow steel pipe pile 1 is connected to the prestressed concrete hardened layer 8, and the bottom is connected to the steel pipe concrete pile drilling 4, and grouting is performed to the crushing bottom plate 11 surrounding rock through the hollow steel pipe pile 1. The cracks 11 in the surrounding rock of the crushing area are filled to improve the integrity of the surrounding rock of the crushing bottom plate 11, and the hollow steel pipe piles 1 are used to reduce the effective span of the bottom plate surrounding rock. At the same time, the surrounding rock of the crushing bottom plate 11 is connected and consolidated with the lower stable surrounding rock. Multiple rock layers of the bottom plate are anchored together in series to form a composite beam structure, which increases the thickness and bending moment resistance of the bottom plate rock layer, and inhibits the sliding bottom drum of the rock layer of the crushing bottom plate 11 under the action of complex stress. It effectively solves the problem that the traditional bottom plate treatment method is difficult to control the sliding bottom drum, and ensures the stability of the loose crushing bottom plate 11 surrounding rock; after the grouting is completed, in order to further reduce the influence of water on the bottom plate surrounding rock, a water-proof hardening layer 9 is laid on the concrete prestressed hardening layer 8, which greatly blocks the contact between water and the bottom plate crushing surrounding rock, which is beneficial to further ensure the stability of the crushing bottom plate 11.

[0025] If the crushing bottom plate 11 has obvious loose crushing bottom drum 12 before laying the concrete prestressed hardening layer 8, it is necessary to refer to Figure 3 and Figure 4 , clean the loose crushing bottom drum 12 on the crushing bottom plate 11 in advance, and lay the concrete prestressed hardened layer 8 on the crushing bottom plate 11 after the bottom plate is leveled to ensure the levelness of the concrete prestressed hardened layer 8.

[0026] Here, the construction method of the present invention can be adjusted according to different site conditions, such as the laying materials and laying thickness of the concrete prestressed hardened layer 8, so as to reduce the support cost while meeting the construction needs.

[0027] After the prestressed concrete hardened layer 8 is laid, the steel tube concrete pile borehole 4 is drilled at an appropriate span according to the width of the tunnel bottom plate by drilling equipment. The steel tube concrete pile borehole 4 extends from the prestressed concrete hardened layer 8 to the surrounding rock stable layer of the crushing bottom plate 11. In the actual construction process, the horizontal spacing of the steel tube concrete pile borehole 4 is designed and optimized according to the actual situation of the crushing bottom plate 11; the depth of the steel tube concrete pile borehole 4 can be calculated by a peep instrument or a bottom plate destruction depth formula, and it is necessary to ensure that the steel tube concrete pile borehole 4 enters the stable rock layer to ensure that the crushing bottom plate 11 has a good sealing effect on the surrounding rock cracks 10 after grouting.

[0028] After drilling the steel tube concrete pile hole 4, the bottom end of the hollow steel tube pile 1 is inserted into the steel tube concrete pile hole 4, the top of the hollow steel tube pile 1 is connected to the concrete prestressed hardened layer 8, and the bottom end is connected to the steel tube concrete pile hole 4 and stabilized in the stable area of ​​the bottom plate surrounding rock. Grouting is then performed through the hollow steel tube pile 1. The grouting slurry 3 can be adjusted according to the on-site geological conditions, but it is necessary to ensure that the steel tube concrete pile formed by the hollow steel tube pile 1 and the grouting slurry 3 has sufficient strength and rigidity to resist the sliding deformation of the bottom plate surrounding rock, and at the same time can block the cracks in the surrounding rock of the broken bottom plate 11. The grouting pressure and grouting speed of the grouting slurry 3 may directly affect the grouting effect, and its process parameters need to be set according to the actual on-site conditions.

[0029] The bottom anchorage of the hollow steel pipe pile 1 can be referred to Figure 5 and Figure 6The bottom end of the hollow steel pipe pile 1 is fixed in the stable rock layer of the bottom plate through the steel pipe concrete pile drilling hole 4, and the hollow steel pipe pile 1 is anchored at the bottom of the steel pipe concrete pile drilling hole 4 by grouting the hollow steel pipe pile 1. During construction, after the hollow steel pipe pile 1 is inserted into the steel pipe concrete pile drilling hole 4, the grouting slurry 3 is injected into the bottom of the steel pipe concrete pile drilling hole 4 through the hollow steel pipe pile 1, and then it needs to be fully contacted and combined with the bottom plate surrounding rock, filling the bottom plate surrounding rock cracks 10 to increase the integrity of the surrounding rock while increasing the overall strength of the hollow steel pipe pile 1. Here, the grouting slurry 3 is specially explained. The grouting slurry 3 can be selected according to the actual situation on site, and there is no fixed material. It needs to be flexibly replaced according to the on-site geological conditions, construction level, construction cost, etc. In this implementation case, due to the low strength of the broken rock mass of the bottom plate and waterproof considerations at the same time, the grouting slurry 3 uses high-strength waterproof materials.

[0030] The top of the hollow steel pipe pile 1 is fixed, which can also be referred to Figure 6 and Figure 7 The reserved part at the top of the hollow steel pipe pile 1 is combined with the square tray 2 and the lock 7 in the supporting structure outside the steel pipe concrete pile drilling hole 4; a drilling hole is reserved in the center of the square tray 2 to facilitate the sleeve connection of the hollow steel pipe pile 1, and the bottom is in contact with the concrete prestressed hardened layer 8; and the lock 7 can pre-tighten the hollow steel pipe pile 1 on the square tray 2.

[0031] The selection of square pallet 2 and lock 7, the pallet and lock can be matched according to the actual situation. The square pallet 2 and threaded lock are currently more commonly used on the market. Therefore, in consideration of construction cost while meeting the test requirements, this case uses square pallet 2 and threaded lock. The threaded lock connects the hollow steel pipe pile 1 to one end of the square pallet 2, so that the top of the hollow steel pipe pile 1 is tightly locked with the square pallet 2.

[0032] At the same time, it was found during the construction process that if the square pallet 2 is in direct contact with the prestressed concrete hardened layer 8, the square pallet 2 may fracture the prestressed concrete hardened layer 8 during the pre-tightening of the hollow steel pipe pile 1 by the lock 7. Therefore, based on the same type of construction technology solutions, an anchor net 6 is added between the square pallet 2 and the prestressed concrete hardened layer 8. The anchor net 6 can disperse the force of the square pallet 2 on the prestressed concrete hardened layer 8 to a great extent, thereby avoiding damage to the prestressed concrete hardened layer 8 due to stress concentration. At the same time, when laying the water-proof hardened layer 9, the anchor net 6 can increase the contact between the water-proof hardened layer 9 and the prestressed concrete hardened layer 8, thereby making them better connected and avoiding stratification.

[0033] The laying of the water-proof hardened layer 9 can be selected according to the actual construction conditions on site. If the site is a hard rock layer and is less affected by water, it can be chosen not to lay it. At the same time, the specific materials and construction technology of the water-proof hardened layer 9 can also be selected according to site needs, as long as the site requirements are met.

Claims

1. A construction method for treating the floor heave problem of a mine tunnel, characterized in that: The construction steps are as follows: Q1. Cleaning the crushing bottom plate (11): Clean the loose crushing bottom drum (12) in the crushing bottom plate (11), restore the original cross-sectional dimensions of the roadway space (5), and keep the crushing bottom plate (11) flat; Q2. Laying a prestressed concrete hardened layer (8): Laying a prestressed concrete hardened layer (8) with concrete on the crushing bottom plate (11); Q3. Drilling a steel tube concrete pile hole (4): Use a mining drilling device to drill a steel tube concrete pile hole (4) on the prestressed concrete hardening layer (8). The steel tube concrete pile hole (4) needs to pass through the prestressed concrete hardening layer (8) and the crushed bottom plate (11), and finally stabilize in the stable rock layer of the bottom plate; Q4. Install the hollow steel pipe pile (1): insert the bottom end of the hollow steel pipe pile (1) into the stable rock layer of the bottom plate along the steel pipe concrete pile drilling hole (4), inject anchoring liquid into the steel pipe concrete pile drilling hole (4) for preliminary fixation of the bottom end of the hollow steel pipe pile (1) and the stable rock layer of the bottom plate, and leave a reserved portion of the top of the hollow steel pipe pile (1) outside the steel pipe concrete pile drilling hole (4); Q5. Grouting: Grouting is carried out through the hollow steel pipe pile (1) toward the broken bottom plate (11). The grouting slurry (3) fills the hollow steel pipe pile (1) to form a high-strength steel pipe concrete pile, and at the same time penetrates and seals the bottom plate surrounding rock cracks (10) under high pressure; Q6. Pre-tightening steel tube concrete piles: An anchor net (6) is laid flat on the concrete prestressed hardened layer (8), the center of the anchor net (6) passes through the hollow steel tube pile (1), a square tray (2) is arranged on the anchor net (6), and the hollow steel tube pile 1 and the square tray (2) are pre-tightened on the concrete prestressed hardened layer (8) by a lock (7); Q7. Laying a water-proof hardened layer (9): Lay a water-proof hardened layer (9) on the prestressed concrete hardened layer (8), bury the hollow steel pipe piles (1), the square tray (2) and the lock (7) in the water-proof hardened layer (9), and complete the construction process after the water-proof hardened layer (9) is hardened and fixed.

2. A construction treatment method for the floor heave problem of a mine tunnel as claimed in claim 1, characterized in that: In Q3, the drilling depth of the steel tube concrete pile hole (4) is based on the depth of the plastic zone of the roadway floor R P Set up; According to the superposition principle of elastic-plastic theory, when the lateral pressure coefficient λ≠1 of deep soft rock tunnel, the surrounding rock stress field is composed of the superposition of original rock stress and deviatoric stress; Assuming that the tunnel surrounding rock is isotropic and in an elastic stress state, the stress calculation formula is as follows: The calculation formula of the equivalent radius of the roadway is: The radius formula of the surrounding rock plastic zone is obtained by using the stress formula and the equivalent radius formula as follows: Where, P0-rock formation self-weight stress; R0-tunnel equivalent radius; R1-tunnel radius; σ θ - tangential stress; σ r - radial stress; R p -Radius of plastic zone; C-cohesion; φ-internal friction angle of rock; h-tunnel height; P1-support resistance; λ-lateral pressure coefficient; θ-polar angle, since λ>1, the polar angle is 90°.

3. A construction treatment method for the floor heave problem of a mine tunnel as claimed in claim 1, characterized in that: In Q3, the spacing between the steel tube concrete pile holes (4) is selected in the range of 800-2000 mm according to an empirical formula and in combination with the site.

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