A construction method for a tunnel in soil-rock strata to cross a pipeline leakage area

Abstract

The present invention belongs to the technical field of tunnel reinforcement and relates to a construction method for a tunnel in a soil-rock stratum passing through a pipeline leakage area. First, taking the rock layer thickness, the range of the leakage area, and the tunnel diameter as parameters, the pipeline leakage type of the tunnel in the soil-rock composite stratum passing through the pipeline leakage area is judged. Then, the local resin normal-temperature curing lining method is used to repair the leaking pipeline, the stratum grouting is used to reinforce the pipeline leakage area, and the upper half-section grouting or the advanced small-diameter pipe grouting is used to reinforce the tunnel construction. Through on-site actual construction verification, it can be applied to the subway tunnel construction under the condition of pipeline leakage in the soil-rock composite stratum and has the value of popularization and application. It divides the underground pipeline leakage range into four types, and corresponding reinforcement means are taken according to the influence of different leakage types on the stability during the tunnel excavation process, including two treatment measures of reinforcing the pipeline leakage area and simultaneously reinforcing the pipeline leakage area and the tunnel construction range, effectively improving the stratum reinforcement quality.

Description

Technical Field:

[0001] The present invention belongs to the technical field of tunnel reinforcement, and particularly relates to a construction method for a tunnel passing through a pipeline leakage area in a soil-rock stratum, and corresponding repair and reinforcement are carried out for the pipeline leakage types in the tunnel passing through the pipeline leakage area in the soil-rock composite stratum. Background Art:

[0002] In recent years, pipeline accidents and ground collapse accidents have occurred frequently during underground tunnel construction, seriously threatening personal safety and wasting project investment. The leakage of underground pipelines is an important inducement for accidents. Affected by the leakage of underground pipelines, the soil layer in the leakage area tends to be saturated, and the mechanical parameters are weakened. Under the softening effect of the stratum passing through the pipeline leakage area, the self-stability of the surrounding rock after being disturbed by tunnel excavation is poor, and excessive deformation is likely to occur. In severe cases, risk accidents such as collapse and rockfall may occur, endangering the safety of tunnel construction. Based on the huge threat posed by the severe leakage or rupture of underground pipelines, especially the upper and lower water pipelines, to tunnel construction, it is necessary to detect the leakage situation of pipelines along the line before actual tunnel excavation, and after detecting the leakage area, classify and grade the severity of the leakage area, and select different reinforcement schemes according to different pipeline leakage situations. For the treatment measures for reinforcing the pipeline leakage area in the soil-rock composite stratum, mainly the in-pipe repair technology is used to plug the pipeline to prevent further leakage, and then the ground grouting method is used to reinforce the saturated and softened soil around the pipeline leakage area. For the tunnel construction stability problem affected by the pipeline leakage in the soil-rock composite stratum, mainly the upper half-section grouting and advanced small pipe grouting are used to ensure the safety and stability of the front heading face during tunnel excavation.

[0003] The current reinforcement methods for pipeline leakage areas mainly include surface grouting and repair of leaking pipelines. Among them, the repair methods for leaking pipelines mainly use trenchless repair technologies, including CIPP in-situ curing method, PVC pipe segment lining method, mechanical spiral winding method, pipe jacking method, pipe bursting method, steel sleeve lining method, spraying method, etc. For example: A method for designing the wall thickness of mortar lining disclosed in Chinese Patent No. 202210953851.2 includes: based on the defect data of the existing pipeline, determining the first equivalent elastic modulus of the existing pipeline under the current state and the second equivalent elastic modulus when reaching the designed service life after repair; based on the line load on the crown of the existing pipeline per unit length and the second equivalent elastic modulus, determining the vertical deformation amount of the crown of the existing pipeline when reaching the designed service life after repair; according to the first equivalent elastic modulus, the second equivalent elastic modulus and the line load on the crown, determining the equivalent additional load required for the existing pipeline to reach the vertical deformation amount of the crown under the current state; based on the equivalent additional load and the assumed value of the mortar lining wall thickness, determining the stress state parameters of the existing pipeline after repair according to the assumed value of the mortar lining wall thickness; comparing the stress state parameters with the standard strength parameters, and judging whether to use the assumed value of the mortar lining wall thickness as the target wall thickness value of the mortar lining according to the comparison result.

[0004] The reinforcement methods in the tunnel excavation area mainly include pipe shed support, sectional grouting, and advanced small pipe grouting, etc. For example, a composite reinforcement method for a shallow-buried tunnel in a soil-rock composite stratum disclosed in Chinese Patent No. 202110297747.8 includes the following steps: S1, surface grouting. A plurality of grouting holes are vertically drilled on the surface above the shallow-buried tunnel to be excavated to form a grouting hole group. In the grouting hole group, the bottom of the grouting hole directly above the shallow-buried tunnel is located on the contour line of the shallow-buried tunnel, and the bottoms of the other grouting holes are located at the soil-rock boundary line. Then, a mixed double slurry of cement slurry and water glass is injected into each grouting hole, and the mouths of each grouting hole are filled and tamped with concrete; S2, pipe shed support. Large-diameter steel pipes are inserted into the surrounding rock arch of the shallow-buried tunnel in order from high to low. The side wall of the large-diameter steel pipe is provided with first holes, and then cement slurry is pressed into the large-diameter steel pipe so that part of the cement slurry flows out from the first holes and consolidates on the surrounding rock arch; S3, advanced small pipe support. First, spray concrete to seal the face of the shallow-buried tunnel and form a grout stop plate on the face. Then, a plurality of support holes are drilled on the grout stop plate in order from high to low. After that, small-diameter steel pipes are inserted into the support holes. The small-diameter steel pipes are simultaneously supported on the steel arch. The side wall of the small-diameter steel pipe is provided with second holes, and then cement slurry is pressed into the small-diameter steel pipe so that part of the cement slurry flows out from the second holes and consolidates. It also discloses a composite reinforcement structure for a shallow-buried tunnel in a soil-rock composite stratum, including a surface soil layer, a rock layer, and a tunnel excavation area; a grouting hole group is formed on the surface, a surrounding rock arch is formed above the tunnel excavation area, a plurality of large-diameter steel pipes arranged obliquely with respect to the horizontal plane are inserted into the surrounding rock arch, the tunnel excavation area has a face, and a steel arch is provided in the tunnel excavation area. A grout stop plate is provided on the face, and small-diameter steel pipes inserted into the face are inserted into the grout stop plate. A composite grouting reinforcement method for a tunnel in a water-rich fine sand layer disclosed in Chinese Patent No. 202210627048.X includes the following steps: Step 1, determine the positions of grouting holes, and determine the drilling positions and drilling angles of grouting holes (2) according to the predetermined reinforcement range; Step 2, composite grouting. 2.1 The first stage is forward grouting, which is used to improve the soil body, reduce the water permeability of the soil body, and improve the hole-forming efficiency for the second-stage grouting reinforcement; 2.2 The second stage is backward grouting, which is used to reinforce the soil body; Step 3, end of grouting.A grouting method for soft rock tunnels disclosed in Chinese Patent No. 202210082711.2 includes the following steps: Step 1: Drill circumferential grouting holes and install anti-corrosion grouting pipes; Step 2: Put in cement, fly ash, bentonite, sand and gravel, and quicklime, add water and stir evenly to form liquid A; Step 3: Stir the water glass stock solution and water evenly to form water glass with a Baume degree of 45°Bé, that is, liquid B; Step 4: Use a grouting pump to transport liquid A to the mixing pump; Step 5: Use a grouting pump to transport liquid B to the mixing pump; Step 6: The mixing pump stirs liquid A and liquid B evenly, and injects the formed grouting slurry into the formation gap around the tunnel through the circumferential grouting holes, and the grouting pressure is 0.5-1.0 Mpa.

[0005] Few patents in the prior art classify and grade the severity of the leakage area according to the actual engineering situation and adopt corresponding reinforcement methods. Therefore, it is necessary to develop and design a repair and reinforcement method for the pipeline leakage type that can target the pipeline leakage area where the tunnel in the soil-rock composite formation passes through. Summary of the Invention:

[0006] The purpose of the present invention is to overcome the shortcomings of the prior art and develop and design a construction method for a tunnel in a soil-rock formation passing through a pipeline leakage area, so as to improve the formation strength and reduce the occurrence of accidents.

[0007] In order to achieve the above purpose, the specific process of the construction method for a tunnel in a soil-rock formation passing through a pipeline leakage area involved in the present invention is as follows: First, taking the rock layer thickness h (the thickness of the rock layer covering the tunnel), the leakage area range hp (the distance between the bottom of the pipeline leakage area and the top of the tunnel), and the tunnel diameter D as parameters, judge the pipeline leakage type of the tunnel in the soil-rock composite formation passing through the pipeline leakage area. Then, adopt one or more of the local resin normal temperature curing lining method, formation grouting, upper half-section grouting, and advanced small pipe grouting for repair and reinforcement. Among them, the local resin normal temperature curing lining method repairs the leaking pipeline, the formation grouting reinforces the pipeline leakage area, and the upper half-section grouting and advanced small pipe grouting reinforce the tunnel construction.

[0008] When h > 0.5D, regardless of the size of hp, adopt the local resin normal temperature curing lining method in the trenchless pipeline repair technology to repair the leaking pipeline and reinforce the pipeline leakage area;

[0009] When h ≤ 0.5D, hp > D, adopt the local resin normal temperature curing lining method and surface grouting to repair the leaking pipeline and reinforce the pipeline leakage area;

[0010] When h ≤ 0.5D, 0.5D < hp ≤ D, adopt the local resin normal temperature curing lining method and advanced small pipe grouting to repair the leaking pipeline, reinforce the pipeline leakage area, and reinforce the tunnel construction;

[0011] When h ≤ 0.5D and hp ≤ 0.5D, ground grouting, upper half-section grouting and advanced small duct grouting are adopted to reinforce the pipeline leakage area and the tunnel construction.

[0012] For the local resin room-temperature curing lining method involved in the present invention, the mass ratio of epoxy resin to curing agent is 1.5 - 2:1; during winter construction, a steam-assisted heating process is adopted to ensure that the curing temperature of the epoxy resin is 5 - 50°C.

[0013] The surface grouting involved in the present invention is the surface rigid sleeve valve pipe segmental backward grouting. The saturated soil body in the pipeline leakage area is grouted and reinforced by drilling from the ground using a mechanical drilling method; the grouting pipe is a steel pipe with a diameter of Φ100×3.5, and an external flange is connected for easy disassembly; the slurry injection range is within 2m in all directions of the pipeline leakage area. The grouting slurry is a mixed double slurry composed of a water glass aqueous solution with a Baume degree of 35 - 40°Bé and an AlCl3 cement slurry with a water-cement ratio of 0.7 - 0.9:1.1 in a mass ratio of 8 - 10:100. The mixed double slurry is filled between the rigid sleeve valve grouting pipe and the grouting hole and inside the rigid sleeve valve grouting pipe. The grouting pressure is 0.4 - 0.5 Mpa, and the grouting speed is 20 - 40 L / min; for the slurry stopping method, an external sleeve valve pipe slurry stopper and an internal double-pipe hydraulic expansion slurry stopper are used; the grouting reinforcement effect is inspected by methods such as core sampling detection method and analysis method.

[0014] The advanced small duct grouting involved in the present invention is carried out before tunnel excavation support. The φ42 advanced small duct grouting pre-support form is adopted. The circumferential and longitudinal spacing of the advanced small ducts is 0.75m×1.5m, the penetration depth is 3m, and the penetration inclination angle is 15° - 20°. The slurry is composed of a cement slurry with a water-cement ratio of 0.9 - 1:1 and a water glass aqueous solution with a mass percentage concentration of 3% in a mass ratio of 1:0.6 - 1; among them, the advanced small duct is a hot-rolled steel pipe with an outer diameter of 42mm, a thickness of 3.5mm, and a length of 3m. The pipe end is in a sharp cone shape to facilitate embedding into the rock and soil stratum. Several overflow holes are reserved on the pipe body in a plum blossom-shaped staggered arrangement for grouting reinforcement. The aperture of the overflow holes is 5mm, and the spacing is 100mm.

[0015] The upper half-section grouting involved in the present invention adopts forward grouting. The slurry is composed of water, phosphoric acid, and water glass in a volume ratio of 12:1:3. The slurry injection range is 2m outside the tunnel excavation line. The grouting pressure is 0.3 - 0.4 Mpa. Grouting is carried out in a clockwise direction from the outside to the inside according to the tunnel section direction. After the circumferential grouting along the excavation line is completed, drilling and grouting are carried out inward in turn.

[0016] Compared with the prior art, the present invention constructs a technical system for controlling the disaster risk of the soil-rock composite stratum in the pipeline leakage area during tunnel crossing based on the concept of "geophysical prospecting positioning - scientific classification - risk control", providing a theoretical basis and prevention and control measures for the construction safety of the subway tunnel in the soil-rock composite stratum passing through the pipeline leakage area; aiming at the influence of different leakage types on the stability during tunnel excavation, corresponding repair and reinforcement means are taken to achieve precise reinforcement, reduce construction time,

[0017] reduce construction costs, effectively reduce the development of surface settlement and the plastic zone of the stratum, improve the stability of the stratum, improve the excavation environment, and ensure the safe and orderly progress of construction. Brief Description of the Drawings:

[0018] Figure 1 It is a schematic diagram of pipeline leakage with small-range leakage in Embodiment 1 related to the present invention.

[0019] Figure 2 It is a schematic diagram of pipeline leakage with large-range leakage in Embodiment 1 related to the present invention.

[0020] Figure 3 It is a schematic diagram of pipeline leakage in Embodiment 2 related to the present invention.

[0021] Figure 4 It is a schematic diagram of pipeline leakage in Embodiment 3 related to the present invention.

[0022] Figure 5 It is a schematic diagram of pipeline leakage in Embodiment 4 related to the present invention.

[0023] Figure 6 It is a construction schematic diagram of the local resin curing lining method related to the present invention.

[0024] Figure 7 It is a construction schematic diagram of surface grouting related to the present invention.

[0025] Figure 8 It is a structural schematic diagram of the rigid sleeve valve grouting pipe related to the present invention.

[0026] Figure 9 It is a construction schematic diagram of upper half-section grouting related to the present invention.

[0027] Figure 10 It is a construction schematic diagram of advanced small pipe grouting related to the present invention.

[0028] Figure 11 It is a layout schematic diagram of the advanced small pipe related to the present invention.

[0029] Figure 12 It is a structural schematic diagram of the advanced small pipe related to the present invention.

[0030] The corresponding relationships marked in the figure are as follows: 1 is the soil layer, 2 is the rock layer, 3 is the tunnel, 4 is the leakage pipeline, 5 is the pipeline leakage area, 6 is the rock layer thickness, 7 is the tunnel diameter, 8 is the range of the leakage area, 9 is the conveying rod, 10 is the repairer, 11 is the rigid sleeve valve grouting pipe, 12 is the mixed double slurry, 13 is the flange, 14 is the grouting hole, 15 is the upper half-section grouting pipe, 16 is the upper half-section grouting hole, 17 is the advanced small pipe, 18 is the body of the advanced small pipe, 19 is the grouting hole of the advanced small pipe, and 20 is the pipe end of the advanced small pipe. Specific implementation method:

[0031] The present invention will be further described below in conjunction with the accompanying drawings and specific implementation methods.

[0032] Example 1:

[0033] When the construction method for a tunnel in a soil-rock stratum passing through a pipeline leakage area involved in this example is applied, for Figure 1-2 the shown rock layer thickness h > 0.5D, regardless of the size of the leakage area range 8, it is repaired and reinforced by the local resin normal-temperature curing lining method. As Figure 6 shown, the specific implementation steps are as follows:

[0034] (1) Seal the pipeline leakage area 5 and clean the repair area of the leakage pipeline 4;

[0035] (2) Cut the fiberglass according to the size of the leakage pipeline 4 to be repaired;

[0036] (3) Mix the epoxy resin and the curing agent in a mass ratio of 2:1 to form a sealing gelling material;

[0037] (4) Apply the sealing gelling material evenly onto the fiberglass to make them fully contact;

[0038] (5) Install the fiberglass on the repairer 10 and position it at the leakage point of the leakage pipeline 4 under the guidance of an endoscopic device through the conveying rod 9;

[0039] (6) Inflate the repairer 10 and maintain the set pressure to make the fiberglass and the leakage point fully bond within the gelling time of the sealing gelling material;

[0040] (7) Release the pressure of the repairer 10 and check the close-fitting condition of the sealing gelling material.

[0041] Example 2:

[0042] When the construction method for a tunnel in a soil-rock stratum passing through a pipeline leakage area involved in this example is applied, for Figure 3 the shown rock layer thickness h < 0.5D and the leakage area range 8 > D, it is repaired and reinforced by the local resin curing lining method and surface grouting. The specific implementation steps are as follows:

[0043] Step 1, local resin curing lining method, and the specific implementation steps are the same as those in Embodiment 1;

[0044] Step 2, surface grouting. As Figure 7 shown, use the surface rigid sleeve valve grouting pipe 11 to grout in a segmented and backward manner. Through mechanical drilling on the ground, grouting reinforcement treatment is carried out on the saturated soil body in the leakage area range 8; after the mixed double slurry 12 is transported from the ground delivery port to the leakage area range 8, it is mixed with the saturated and softened soil body. Through the extrusion effect, the soil density is increased, and through the wrapping effect, a protective shell is formed to realize the hardening of the soil body in the leakage area range 8, and the safety risk induced by tunnel construction is reduced to the greatest extent.

[0045] The specific construction steps of surface grouting are as follows:

[0046] (1) Measure and set the hole positions;

[0047] (2) Use mechanical drilling to drill to the designed depth;

[0048] (3) Configure and inject the casing material;

[0049] (4) Install the rigid sleeve valve grouting pipe 11;

[0050] (5) Seal and fix the rigid sleeve valve grouting pipe 11;

[0051] (6) Prepare the mixed double slurry 12 and wait for it to set;

[0052] (7) Open the loop for grouting;

[0053] (8) From bottom to top, grout in a segmented and intermittent backward manner;

[0054] (9) Clean the rigid sleeve valve grouting pipe 11;

[0055] (10) End of grouting.

[0056] Embodiment 3:

[0057] When the construction method for the tunnel crossing the pipeline leakage area in the soil-rock stratum involved in this embodiment is applied, for Figure 4 shown, the rock layer thickness h < 0.5D, 0.5D < leakage area range 8 < D, repair and reinforcement are carried out through the local resin curing lining method and the advanced small pipe grouting. The specific implementation steps are as follows:

[0058] Step 1, local resin curing lining method, and the specific implementation steps are the same as those in Embodiment 1;

[0059] Step 2, advanced small pipe grouting

[0060] (1) Advanced geological exploration and geological survey;

[0061] (2) Prepare the grouting slurry for the advanced small pipe.

[0062] (3) Check the grouting effect through on-site tests.

[0063] (4) Formulate the construction plan for the advanced small pipe and make construction preparations.

[0064] (5) Spray concrete to seal the tunnel face.

[0065] (6) Use mechanical drilling to drive in the advanced small pipe 17.

[0066] (7) Conduct grouting.

[0067] (8) Tunnel excavation.

[0068] Example 4:

[0069] When the construction method for a tunnel in a soil-rock stratum passing through a pipeline leakage area involved in this example is applied, for the Figure 5 shown rock stratum thickness h < 0.5D and leakage area range 8 < 0.5D, repair and reinforcement are carried out through the local resin curing lining method, upper half-section grouting, and advanced small pipe grouting. The specific implementation steps are as follows:

[0070] Step 1, the local resin curing lining method, and the specific implementation steps are the same as those in Example 1.

[0071] Step 2, surface grouting, and the specific implementation steps are the same as those in Example 2.

[0072] Step 3, upper half-section grouting

[0073] (1) Measure and mark the holes, and mark them on the tunnel face with paint.

[0074] (2) Position and fix the drill rig platform.

[0075] (3) Confirm and fix the drill rig platform and the pitch and roll angles.

[0076] (4) Open the hole and install the orifice pipe.

[0077] (5) Install the dust collector.

[0078] (6) Drill the grouting holes.

[0079] (7) Prepare the grouting slurry for the upper half-section.

[0080] (8) Conduct grouting.

[0081] (9) Check the grouting effect by drilling grouting effect inspection holes.

[0082] Step 4, advanced small pipe grouting, and the specific implementation steps are the same as those in Example 3.

Claims

1. A construction method for a tunnel in a soil-rock stratum to cross a pipeline leakage area, characterized in that The specific technological process is as follows: First, taking the rock stratum thickness h, the leakage area range hp, and the tunnel diameter D as parameters, determine the pipeline leakage type of the tunnel passing through the pipeline leakage area in the soil-rock composite stratum. Then, use one or more of the following methods for repair and reinforcement: local resin normal-temperature curing lining method, ground grouting, upper half-section grouting, and advanced small pipe grouting: When h > 0.5D, regardless of the size of hp, adopt the local resin normal-temperature curing lining method in the trenchless pipeline repair technology to repair the leaking pipeline and reinforce the pipeline leakage area; When h ≤ 0.5D and hp > D, adopt the local resin normal-temperature curing lining method and surface grouting to repair the leaking pipeline and reinforce the pipeline leakage area; When h ≤ 0.5D and 0.5D < hp ≤ D, adopt the local resin normal-temperature curing lining method and advanced small pipe grouting to repair the leaking pipeline, reinforce the pipeline leakage area, and reinforce the tunnel construction; When h ≤ 0.5D and hp ≤ 0.5D, adopt ground grouting, upper half-section grouting, and advanced small pipe grouting to reinforce the pipeline leakage area and reinforce the tunnel construction; Among them, the local resin normal-temperature curing lining method repairs the leaking pipeline. During winter construction, the steam-assisted heating process is adopted to ensure that the curing temperature of the epoxy resin is 5 - 50°C.

2. The construction method for a tunnel in soil-rock strata passing through a pipeline leakage area according to claim 1, wherein The surface grouting is the surface rigid sleeve valve pipe segmental backward grouting. The mechanical drilling method is used to drill holes from the ground to grout and reinforce the saturated soil in the pipeline leakage area; the grouting pipe is a steel pipe with a diameter of Φ100×3.5, and an external flange is connected; the slurry injection range is within 2m in all directions of the pipeline leakage area, the grouting pressure is 0.4 - 0.5 Mpa, and the grouting speed is 20 - 40 L / min; for the grout stopping method, an external sleeve valve pipe grout stopper and an internal double-pipe hydraulic expansion grout stopper are used; after completion, the core sampling detection method, analysis method, etc. are used to inspect the grouting reinforcement effect.

3. The construction method for a tunnel passing through a pipeline leakage area in a soil-rock stratum according to claim 1 or 2, characterized in that, The advanced small pipe grouting is carried out before the tunnel excavation support. The φ42 advanced small pipe grouting pre-support form is used to reinforce the tunnel construction. The circumferential and longitudinal spacing of the small pipes is 0.75m×1.5m, the penetration depth is 3m, and the penetration inclination angle is 15° - 20°. The slurry is composed of cement slurry with a water-cement ratio of 0.9 - 1:1 and an aqueous solution of sodium silicate with a mass percentage concentration of 3% in a mass ratio of 1:0.6 - 1.

4. The construction method for a tunnel in soil-rock stratum passing through a pipeline leakage area according to claim 1, characterized in that, The upper half-section grouting adopts the forward grouting method to reinforce the tunnel construction. The slurry injection range is 2m outside the tunnel excavation line, the grouting pressure is 0.3 - 0.4 Mpa, and the grouting is carried out in the clockwise direction from the outside to the inside according to the tunnel section direction. After the peripheral circumferential grouting along the excavation line is completed, the drilling and grouting are carried out inward in turn.

5. The construction method for a tunnel in soil-rock stratum passing through a pipeline leakage area according to claim 1, characterized in that, The mass ratio of the epoxy resin to the curing agent used is 1.5 - 2:

1.

6. The construction method for a tunnel in soil-rock stratum passing through a pipeline leakage area according to claim 2, characterized in that, The slurry for surface grouting is a mixed double slurry composed of an aqueous solution of sodium silicate with a Baume degree of 35 - 40°Bé and an AlCl3 cement slurry with a water-cement ratio of 0.7 - 0.9:1.1 in a mass ratio of 8 - 10:

100. The mixed double slurry is filled between the rigid sleeve valve grouting pipe and the grouting hole and inside the rigid sleeve valve grouting pipe.

7. The construction method for a tunnel in a soil-rock stratum passing through a pipeline leakage area according to claim 3, characterized in that, The advanced small duct is a hot-rolled steel pipe with an outer diameter of 42 mm, a thickness of 3.5 mm, and a length of 3 m. The pipe end is in a sharp cone shape, and several slurry overflow holes are reserved on the pipe body, arranged in a staggered plum blossom pattern. The aperture of the slurry overflow holes is 5 mm, and the spacing is 100 mm.

8. A construction method for a tunnel in soil-rock stratum passing through a pipeline leakage area according to claim 4, characterized in that, The grouting slurry for the upper half section is composed of water, phosphoric acid, and water glass in a volume ratio of 12:1:3.

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