1. A construction method for mud burst and water burst of a tunnel is characterized by comprising the steps of constructing a grout stop wall in a tunnel A, grouting and reinforcing a tunnel face in a step B, pre-supporting and arch sheathing supporting a pipe shed in advance in a step C, grouting and reinforcing radially in a step D, and encrypting, monitoring and measuring distribution points in a step E;

and step E is implemented when the step A, the step B, the step C and the step D are carried out simultaneously, and hydrostatic pressure, water quantity and mud gushing quantity are measured for judging the treatment effect of treating mud gushing and water gushing in each step.

2. The method of claim 1, wherein a grout stop wall is constructed in the hole in step A; when the distance between slurry in the tunnel and the tunnel face reaches 3m, the construction is stopped, massive prefabricated parts and tunnel ballast are adopted in the process of constructing the slurry stop wall, construction is carried out in three steps, and a drain pipe, a grouting pipe and an orifice pipe are buried in each stage of the slurry stop wall, so that the slurry stop wall is used as drilling guide of a grouting hole in case that the grouting pipe is flushed out during tunnel drainage, grouting and grouting.

3. The method according to claim 1, wherein the tunnel face is reinforced by grouting in step B; after a grout stop wall is constructed in a hole, judging whether the geological condition of constructing a pipe shed in the hole is a fault fracture zone or not, grouting and reinforcing a tunnel face in the process of constructing the pipe shed in the hole, arranging a pipe shed construction working chamber at the rear section of the working face, and setting the size of the pipe shed construction working chamber in combination with the construction space of the pipe shed; the area of the cross section is increased, supporting parameters are properly improved, the length of a grouting pipe on the tunnel face is 4-5.5 m, the distance between adjacent steel pipes is 1.0m and the grouting pipe is arranged in a quincunx shape, grouting is carried out in a horizontal grouting mode, the water-cement ratio of a grouting material is controlled to be 0.4-0.6, the grouting pressure is controlled to be 0.5-1.0 MPa, and the optimal slurry mixing ratio and the optimal grouting pressure need to be determined through field tests before formal grouting.

4. The method according to claim 1, wherein the step C comprises pre-supporting the pipe shed in advance and supporting the pipe shed with an arch; after grouting reinforcement of the tunnel face is completed, the guide pipe is arranged on the cover arch and used as a fixed end of the pipe shed, and the angle and the direction of the pipe shed erection are controlled by the guide pipe, so that the accuracy of the construction direction of the pipe shed is ensured.

5. The method for constructing mud and water burst in a tunnel according to claim 4, wherein the fixed end of the pipe shed is a sleeve arch, the I-shaped steel is arranged in the sleeve arch, the orifice pipe and the I-shaped steel are welded together, the steel arch, the reinforcing mesh and the orifice pipe are welded in a double-sided welding mode, the length of a welding seam is ensured to be more than 2.5d-3d (d is the diameter of the orifice pipe), the sleeve arch is made of concrete, and the early strength agent is properly added according to actual construction conditions;

in the pipe shed construction process, in order to ensure the stability of the cover arch construction and properly use the temporary support to improve the stability of the cover arch, the pipe shed is made of hot-rolled seamless steel pipes with the wall thickness of 8mm, the spacing of the steel pipes is controlled to Be 0.3m, the elevation angle is controlled to Be 2-3 degrees, cement-water glass slurry is used as grouting liquid in the pipe shed grouting process, the volume ratio of the cement-water glass slurry is controlled to Be 1: 0.3-1: 1, and the water glass concentration is controlled to Be 30-35 Be'.

6. The method for constructing mud-bursting and water-bursting tunnel according to claim 1, wherein the step D is implemented by radial grouting reinforcement; the method comprises the steps of performing radial grouting to pre-support the tunnel after pipe shed advanced pre-support and arch support, using steel perforated pipes with the length of 4.5M, controlling the longitudinal spacing of the steel perforated pipes to be 1.5M, controlling the circumferential spacing to be 0.6M, ensuring that the inclined angle is inclined upwards by 60 degrees, wherein in the construction stage, all pipe length and grouting depth parameters need to be strictly performed according to the construction design, determining the optimal grouting pressure and optimal mixing ratio parameters through field tests before starting comprehensive grouting work, adopting M30 cement mortar as grouting materials when grouting construction is carried out, controlling the water cement ratio to be (0.5-0.8) to 1, adding an appropriate amount of water glass or calcium chloride, dividing grouting into initial pressure and final pressure, controlling the initial pressure to be 0.5-1.0 MPa, controlling the final pressure to be 2.0MPa, and strictly performing grouting from two sides to the arch crown direction.

7. The method of claim 1, wherein the step E of encrypting the monitoring and measuring distribution points to perform monitoring and measuring determines the effect of water burst and mud burst treatment; the monitoring measurement comprises monitoring measurement during construction and monitoring measurement during operation, the monitoring measurement during construction strengthens hydrological measurement and observation, measures hydrostatic pressure, water quantity and mud gushing quantity, observes changes of groundwater water quantity and water pressure and whether mud burst or siltation occurs, monitors and measures the change condition of strengthened groundwater and measures the stress and deformation condition of a tunnel structure during operation, and continuously monitors the primary support and secondary lining deformation, stress condition and hydrological condition of the inclined shaft tunnel.

Background

The tunnel construction is influenced by various adverse geological disasters, wherein mud burst and water burst are the problems frequently occurring in tunnel construction in a water-rich area, the tunnel water burst can destroy the ecological environment for a long time, so that the problems of worsening construction conditions, threatening lining safety in the tunnel operation period and the like can be caused, and engineering geological disasters can be even caused seriously, so that the research on the tunnel water burst treatment has strong practical significance.

The water leakage treatment of the existing tunnel adopts a plugging method, the water leakage can be blocked by the plugging method, however, the water flow is easy to diffuse and is disorderly scurried to cause uncontrollable water catastrophe, fine particles in tunnel surrounding rocks are easy to flow out due to the water leakage, the broken surrounding rock structure is locally hollowed and collapsed, the water pressure rising caused by the plugging can threaten the stability of the lining, the safety of the tunnel construction and the operation period is influenced, the water leakage is greatly deteriorated in the tunnel construction environment, and the construction difficulty is increased.

Disclosure of Invention

In order to overcome the defects of the prior art, the invention provides a construction method for tunnel mud-bursting and water-flushing.

The method comprises the steps of A, treating measures in a tunnel, B, grouting and reinforcing a tunnel face, C, pre-supporting and arch supporting a pipe shed in advance, D, radially grouting and reinforcing, and E, encrypting, monitoring and measuring and distributing points.

And step E is implemented when the step A, the step B, the step C and the step D are carried out simultaneously, and the hydrostatic pressure, the water quantity and the mud gushing quantity are measured and used for judging the treatment effect of treating the mud gushing and the water gushing in each step.

And further, constructing a grout stopping wall in the step A, stopping construction when the distance between slurry in the tunnel and the tunnel face reaches 3m, applying massive prefabricated parts and tunnel ballast in the process of constructing the grout stopping wall, and constructing in three steps, wherein each level of grout stopping wall needs to embed a certain number of drain pipes, grouting pipes and orifice pipes for drilling guide of grouting holes in case that the grouting pipes are flushed out during tunnel drainage, grouting and grouting.

Through the technical scheme, the drainage and grouting work in the tunnel can be completed.

Further, grouting and reinforcing the tunnel face in the step B; the geological condition of the pipe shed in the tunnel is usually a fault fracture zone, and the tunnel face must be reinforced by grouting firstly in the process of carrying out the construction of the pipe shed in the tunnel. The method comprises the steps of arranging a pipe shed construction working chamber at the rear section of a working face, wherein the excavation radius of the pipe shed construction working chamber is generally larger than the normal excavation radius, if the area of a cross section is increased, the support parameters are properly improved, the length of a grouting pipe of a tunnel face is about 4-5.5 m, the distance between adjacent steel pipes is about 1.0m, the grouting pipe is arranged in a quincunx shape, horizontal grouting is applied to perform concrete grouting, cement ash of grouting materials is controlled between (0.6-3.0) and 1, grouting pressure is controlled between 0.5-1.0 MPa, and the optimal slurry mixing ratio and grouting pressure are determined through field tests before formal grouting.

Through the technical scheme, the excavation work can be ensured to be carried out stably and smoothly.

Further, C, pre-supporting and arch supporting the pipe shed in advance; after grouting reinforcement of the tunnel face is completed, installing a guide pipe on the cover arch to serve as a fixed end of the pipe shed, controlling the angle and the direction of the pipe shed building by using the guide pipe, arranging I-shaped steel inside the cover arch, and welding the orifice pipe and the I-shaped steel together; welding the steel arch, the reinforcing mesh and the orifice pipe by using a double-sided welding mode, and ensuring that the length of a welding seam exceeds 5 d; the cover arch is made of concrete, and the early strength agent can be properly added according to the actual construction condition. In the pipe shed construction process, in order to ensure the stability of the cover arch construction, the temporary support can be properly used to improve the stability of the cover arch. The pipe shed is made of hot-rolled seamless steel pipes with the wall thickness of 8mm, the spacing between the steel pipes is controlled to Be about 0.3m, the elevation angle is controlled to Be 2-3 degrees, cement-water glass slurry is used as grouting liquid in the grouting process of the pipe shed, the volume ratio is controlled to Be 1: 0.3-1: 1, and the water glass concentration is controlled to Be 30-35 Be'.

Through the technical scheme, the accuracy of the construction direction of the pipe shed can be ensured.

Further, D, radial grouting reinforcement is performed; the method comprises the steps of performing radial grouting to pre-support the tunnel after advanced pre-support and arch support of a pipe shed, generally applying steel perforated pipes with the length of 4.5M, controlling the longitudinal spacing of the steel perforated pipes to be 1.5M and the circumferential spacing to be 0.6M, ensuring that the inclined angle inclines upwards by 60 degrees, wherein in the construction stage, all pipe length and grouting depth parameters need to be strictly performed according to the construction design, before the comprehensive grouting work is started, the optimal grouting pressure and optimal matching ratio parameters need to be determined through field tests, when grouting construction is performed, M30 cement mortar is generally applied as grouting materials, the water cement ratio is controlled to be (0.5-0.8): 1, a proper amount of water glass or calcium chloride is added, the grouting is divided into initial pressure and final pressure, the initial pressure is controlled to be 0.5-1.0 MPa, the final pressure is generally 2.0MPa, and the grouting is strictly performed from two sides to the vault.

Through the technical scheme, the tunnel construction safety can be further ensured.

Further, step E, encrypting the monitoring measurement distribution points; the monitoring measurement comprises monitoring measurement during construction and monitoring measurement during operation, the monitoring measurement during construction is used for enhancing hydrological measurement and observation, measuring hydrostatic pressure, water quantity and mud burst quantity, observing groundwater water quantity change and water pressure change and observing whether mud burst or siltation occurs, the monitoring measurement during operation is used for enhancing measurement of groundwater change conditions and tunnel structure stress and deformation conditions, and continuously monitoring inclined shaft tunnel primary support and secondary lining deformation, stress conditions and hydrological conditions.

In conclusion, the method provided by the invention can effectively control the water flow diffusion of the mud inrush and water inrush of the tunnel, limit the influence caused by the mud inrush and water inrush in a controllable range, and simultaneously does not influence the tunnel construction environment.

Drawings

FIG. 1 is a schematic view of a grout stop wall of the present invention;

FIG. 2 is a schematic cross-sectional view of the treatment of the present invention.

Detailed Description

It should be noted that the embodiments and features of the embodiments can be combined with each other without conflict, and the present application will be further described in detail with reference to the drawings and specific embodiments.

Tunnel zone bedrock nature is more close the granite, belongs to mixed rock, and the weathering leads to near tunnel site rock mass breakage, and along with the motion of geological structure, inside broken rock mass can slowly enter into the country rock, and then caused tunnel and near regional geological conditions in tunnel very complicated.

Two regional faults exist around the tunnel, one of the two regional faults is a north-south trend normal fault and is marked as an F1 fault, the other one is an east-west trend normal fault and is marked as an F2 fault, the F1 fault inclines towards the west, and the other tunnel is located on the west side of the F1 fault, so that the surrounding rock mass is severely crushed due to the influence of the F1 fault, and the stability is poor. In addition, the F1 fault is used as a water guide fault and contains more fracture water, and in the process of tunnel excavation, the influence of the fracture water causes a larger water inflow amount in a hole, the F2 fault inclines to the south, and the F1 fault and the F2 fault are intersected near a certain country. The rock mass is seriously broken due to the influence of two faults, and the rock mass is stripped into mineral fine particles due to long-time weathering, a certain amount of atmospheric precipitation is stored in the gap, and the mineral fine particles and the atmospheric precipitation are mixed with each other to form slurry.

The country rock of tunnel exit position mainly is apoplexy metaplasia country rock, and the country rock has better wholeness, and the stratum plays isolated groundwater's effect, leads to groundwater to gather in broken rock mass, leads to groundwater drainage to be not smooth and easy, rises gradually along with the water level, and the supply forms stable groundwater with excrete after balancing each other.

The water level is relatively higher, and the position of face is usually lower than groundwater level, so, the water pressure that the face bore is great, and after the completion blasting, the water barrier can be broken through, and mineral fine grain and clay can be washed out along with groundwater, finally cause the condition of gushing water and sudden mud.

The technical scheme adopted by the invention is that as underground water develops, mud outburst and water burst possibly occur during construction, so that karst and broken zone development sections endangering construction safety are generated, surrounding rocks are reinforced by grouting and water blocking according to the principle of 'drainage and blocking combination and comprehensive treatment', mud outburst and water burst are prevented, construction safety is ensured, and the water control principle of 'dredging, guiding and draining as a main part' is adopted for karst pipeline water and underground rivers revealed during construction at sections without influencing the surface environment.

The section that the groundwater loss that leads to tunnel excavation probably arouses the earth's surface environmental change and influences resident's production domestic water adopts "taking stifled waterproof measure as the main", and the measure includes treatment in the hole measure, tunnel face slip casting reinforcement, pipe shed advance preliminary bracing and cover arch support, radial slip casting reinforcement, encryption control measurement stationing.

The method comprises the steps of constructing a grout stop wall in a tunnel A, grouting and reinforcing a tunnel face B, pre-supporting and arch-sleeving supporting a pipe shed C, radially grouting and reinforcing the pipe shed D, and encrypting, monitoring and measuring points E.

As shown in FIG. 1, in the present invention, a grout stop wall is constructed in a hole; the construction method is characterized in that a grout stopping wall is constructed in a tunnel, construction is stopped when the distance between slurry in the tunnel and a tunnel face reaches 3m, massive prefabricated parts and tunnel ballast need to be applied in the process of constructing the grout stopping wall, construction is carried out in three steps, and a certain number of drain pipes, grouting pipes and orifice pipes need to be buried in each level of the grout stopping wall, and the grout stopping wall is used as drilling guide of grouting holes in case that the grouting pipes are flushed out during tunnel drainage, grouting and grouting.

In the invention, the tunnel face is reinforced by grouting; the geological condition of the pipe shed in the tunnel is usually a fault fracture zone, and in the process of carrying out the construction of the pipe shed in the tunnel, in order to ensure that the excavation work is carried out stably and smoothly, the tunnel face must be reinforced by grouting at first. The pipe shed construction working chamber is arranged at the rear section of the working surface, generally speaking, compared with the normal excavation radius, the excavation radius of the pipe shed construction working chamber is relatively larger, and the size of the pipe shed construction working chamber is reasonably arranged in combination with the construction space of the pipe shed;

if the area of the cross section is increased, the support parameters are properly improved, the length of a grouting pipe on the tunnel face of the tunnel is about 4-5.5 m, the distance between adjacent steel pipes is about 1.0m and the grouting pipes are arranged in a quincunx shape, grouting is carried out by applying a horizontal grouting mode, cement ash of a grouting material is controlled to be 0.4-0.6, grouting pressure is controlled to be 0.5-1.0 MPa, and the optimal slurry mixing ratio and grouting pressure are determined through field tests before formal grouting.

In the invention, the pipe shed is supported in advance and is supported by an arch; after grouting reinforcement of the tunnel face is completed, a guide pipe is arranged on the cover arch to serve as a fixed end of the pipe shed, and the angle and the direction of the erection of the pipe shed are controlled by the guide pipe, so that the accuracy of construction directions of the pipe shed is ensured; the fixed end of the pipe shed is a sleeve arch, I-shaped steel is arranged in the sleeve arch, and the orifice pipe and the I-shaped steel are welded together; welding the steel arch, the reinforcing mesh and the orifice pipe by a double-sided welding mode, and ensuring that the length of a welding seam exceeds 2.5d-3d (d is the diameter of the orifice pipe); the sleeve arch is made of concrete, and an early strength agent can be properly added according to the actual construction condition; in the pipe shed construction process, in order to ensure the stability of the cover arch construction, the temporary support can be properly used to improve the stability of the cover arch. The pipe shed is made of hot-rolled seamless steel pipes with the wall thickness of 8mm, the spacing of the steel pipes is controlled to be about 0.3m, and the elevation angle is controlled to be 2-3 degrees; in the pipe shed grouting process, cement-water glass slurry is used as grouting slurry, the volume ratio of the cement-water glass slurry is controlled to Be 1: 0.3-1: 1, and the water glass concentration is controlled to Be 30-35 Be'.

In the invention, radial grouting reinforcement is carried out; in order to further ensure the safety of tunnel construction, before tunnel excavation construction, radial grouting must be carried out to pre-support the tunnel, steel perforated pipes with the length of 4.5m are generally applied, the longitudinal distance between the steel perforated pipes is controlled to be about 1.5m, the circumferential distance is controlled to be 0.6m, the inclination angle is ensured to be inclined upwards by 60 degrees, and in the construction stage, all pipe length and grouting depth parameters must be strictly carried out according to the construction design; before the full grouting work is started, the optimal grouting pressure and the optimal mixing ratio parameters must be determined through field tests. When grouting construction is carried out, M30 cement mortar is generally used as a grouting material, the water cement ratio is controlled to be (0.5-0.8) to 1, a proper amount of water glass or calcium chloride is added, grouting is divided into initial pressure and final pressure, the initial pressure is controlled to be 0.5-1.0 MPa, the final pressure is generally 2.0MPa, and grouting is strictly carried out from two sides to the vault.

In the invention, the construction process comprises the following steps:

1, comprehensively and advance geology forecast is carried out in front of and around the face of the tunnel, and the hole distribution, the water pressure and the filling condition are mastered;

2, under the condition of ensuring safety, uncovering all karst caves in a small range and a small size by controlling blasting;

3, orderly danger elimination, water pumping, dredging and danger elimination;

4, connecting anchor rods in the solution cavity of the construction arch wall and spraying concrete protective shells on steel frames outside the backfill layers of the side walls, burying the main solution cavity and reserving in the karst pipelinesA drainage steel pipe and a concrete pumping pipe.

And 5, constructing a primary support, and constructing a horizontal I-shaped steel bracket at the position of the cross hole.

And 6, removing sludge fillers in the karst cave with the range of 5.0m at the bottom of the inverted arch, performing layered compaction and replacement filling by adopting cave dregs and backfilling C20 concrete, and constructing the reinforced concrete joist as shown in figure 2.

Dredging the dissolving cavity behind the primary support of the arch wall, arranging necessary temporary supports, and backfilling and plugging the dissolving cavity and the karst pipeline by (layering) pumping C35 concrete;

8, performing radial system grouting, and sequentially adoptingDrilling to inject cement mortar and pure cement slurry into the surrounding rock, and performing supplementary grouting until the inspection and acceptance requirements are met;

and 9, performing inverted arch filling in time.

And 10, performing secondary lining in due time according to the hydrological monitoring condition and the grouting water plugging effect.

In the invention, measurement is monitored; the monitoring measurement comprises monitoring measurement during construction and monitoring measurement during operation, wherein the monitoring measurement during construction is used for enhancing hydrological measurement and observation, measuring hydrostatic pressure, water quantity and mud burst quantity, and observing underground water quantity change, water pressure change and whether mud burst or siltation occurs or not; during operation, the monitoring measurement shall strengthen the measurement of underground water change condition and tunnel structure stress and deformation condition, and continue to monitor the inclined shaft tunnel primary support and secondary lining deformation, stress condition and hydrological condition.

The method provided by the invention can effectively control the water flow diffusion of the mud inrush and water inrush of the tunnel, limit the influence caused by the mud inrush and water inrush in a controllable range, and simultaneously does not influence the tunnel construction environment.

Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.