CN116771374A - Double-ring hoop-shaped grouting reinforcement structure for tunnel underpass existing pipeline and construction method thereof - Google Patents

Abstract

This application discloses a double-ring hoop-shaped grouting reinforcement structure for a tunnel to pass through an existing pipeline and a construction method thereof. The structure includes a double-ring hoop-shaped grouting reinforcement area, including an arc-shaped solidification belt located below the pipeline, and the arc-shaped solidification belt. The semicircular grouting reinforcement zone connected and wrapped by the shaped solidification belt and the grouting isolation zone semi-surrounded by the pipe are formed by injecting the grouting isolation zone into the semicircular grouting channel. It is made of ultra-high performance cement slurry filled with composite fibers. This application adopts micro-disturbance trenchless grouting reinforcement technology, which eliminates the need for overall excavation of the overlying soil of underground pipelines, greatly saving pipeline reinforcement costs; it is extremely applicable both in densely populated urban areas and in uninhabited areas with complex terrain. , and has little impact on the surrounding strata, landforms, vegetation and other natural landscapes, and has a certain environmental protection effect. It is especially suitable for the reinforcement construction of underground large-diameter and ultra-long pipelines in key projects under disturbance from other constructions.

Description

Double-ring hoop-shaped grouting reinforcement structure for tunnel underpass existing pipeline and construction method thereof

Technical Field

The application relates to the technical field of underground pipeline safety control, in particular to a double-ring hoop-shaped grouting reinforcement structure for a tunnel underpass existing pipeline and a construction method thereof.

Background

The underground pipeline is responsible for urban gas transmission, water transmission, power transmission, communication, pollution discharge and the like, and the normal operation of urban life is ensured by the normal operation of the underground pipeline, so that the underground pipe network system plays a vital role in urban resident life and production construction. Meanwhile, as the urban mass of China is continuously accelerated, the population density of cities is gradually increased, and the number and the length of underground pipelines are also increased year by year. The existing underground pipeline laying modes include an upper burying mode, a ditch burying mode and a tunnel mode, and after pipelines are buried into the stratum by different burying modes, the pipeline can be acted on the pipeline during normal operation of the pipeline no matter whether the pressure existing in the pipeline or the pressure of an external soil body exists. Namely, the pipeline is mainly subjected to internal pressure, surrounding soil load, overlying traffic load and the like in an initial stable state.

However, in the tunnel construction process under the existing underground pipeline, the stratum is disturbed to deform due to tunnel excavation, the stratum deformation further generates additional stress and additional deformation on the underground pipeline, and when the additional stress generated by the tunnel construction applied to the pipeline exceeds the deformation resistance of the pipeline, the pipeline can generate damage forms such as leakage, fracture, overlarge deformation, explosion and the like. And because the underground pipeline belongs to hidden engineering, the sedimentation deformation control and maintenance of the existing underground pipeline are more difficult compared with the above-ground facilities. According to the application, on the basis of an indoor model test, an outer ring hoop reinforcement treatment technology is carried out on the existing pipeline, and the tunnel excavation model test shows that in the diameter range of 2 times of tunnel excavation, the deformation and stress generated by the pipeline can be greatly reduced on the reinforcing hoop of the existing pipeline above, the maximum sedimentation value and the maximum positive and negative bending moment value of the pipeline are smaller than those of the underground pipeline which is not subjected to reinforcement hoop treatment, and the integral rigidity of the underground pipeline is increased, the deformation resistance and stress resistance are increased, and the influence of tunnel excavation on the disturbance effect of the underground pipeline can be reduced through the local node reinforcement effect of the pipeline.

Disclosure of Invention

The application aims to provide a double-ring hoop grouting reinforcement structure for a tunnel penetrating through an existing pipeline and a construction method thereof, which are used for restraining an underground pipeline in a circumferential direction through an annular grouting hardening area formed around the pipeline, so that further sedimentation deformation of the pipeline caused by soil sedimentation is reduced, additional bending moment generated by bending deformation of the pipeline is reduced, and disturbance influence of tunnel construction on the underground pipeline is reduced, and at least one technical problem related to the background technology can be solved.

In order to solve the technical problems, the application is realized as follows:

the embodiment of the application provides a double-ring hoop-shaped grouting reinforcement structure for a tunnel to penetrate through an existing pipeline, which comprises the following components:

the double-hoop grouting reinforcement area comprises an arc-shaped solidification area positioned below a pipeline, a semicircular grouting reinforcement area connected with the arc-shaped solidification area and wrapping the pipeline, and a grouting isolation area arranged to semi-surround the pipeline, wherein the grouting isolation area is formed by grouting and filling composite fiber ultra-high-performance cement grouting material in a semicircular grouting channel in the grouting isolation area.

Optionally, the composite fiber ultra-high performance cement grouting material comprises, by weight, 290-310 parts of 42.5-grade ordinary Portland cement slurry, 15 parts of water glass, 20 parts of primary fly ash, 15 parts of S75-grade slag, 43 parts of secondary silica fume, 3 parts of naphthalene sulfonate water reducer, 38 parts of complex recycled fiber and 100-120 parts of water.

Optionally, the water-cement ratio of the 42.5-grade ordinary Portland cement slurry is 0.4-0.6; the seepage rate of cement slurry is not more than 3-8%; the naphthalene sulfonate water reducer is a high-performance water reducer with the water reducing rate of 18-25%.

Optionally, the complex recycled fiber comprises common steel fiber and waste tire recycled steel fiber, the length-diameter ratio is 45-50, and the length is 3mm, 5mm and 7mm according to the following ratio of 4:2:1 by mass ratio.

Optionally, one end of the double-ring hoop-shaped grouting reinforcement area is communicated with a grouting end, and the other end is communicated with a grouting end; the depth of downward excavation of the slurry inlet end and the slurry outlet end is 25-100 cm under the average elevation of the flat site, and the length and the width of the excavation area are respectively 6 times of the diameter of the semicircular grouting channel of the double-ring hoop-shaped grouting reinforcement area.

Optionally, the semicircular grouting reinforcement area is formed by grouting around the pipeline through a drilling machine, a grouting guide pipe connecting device and a vertical grouting guide pipe; the grouting pipe connecting device is formed by connecting 1 cross-shaped grouting main pipe, 5 vertical grouting connecting pipes, 2L-shaped grouting connecting pipes, 4 pipeline connecting tee joints and a plurality of grouting sleeves through threads; the vertical grouting guide pipe is made of steel grouting guide pipe with the diameter of 32mm, three grouting outlets are formed in the section of the same height of the guide pipe, the included angles of the grouting outlets are 120 degrees, and grouting holes are formed in the end part of the grouting guide pipe, so that grouting reinforcement of the grouting guide pipe in all directions is ensured.

Optionally, the arc-shaped curing belt is formed by grouting a grouting hose with a grouting outlet by a grouting pump in a semicircular grouting channel drilled by a drill bit, a drill control wire and a drill central control system acquisition vehicle in cooperation with a drill; the grouting isolation belt is formed by grouting in a semicircular grouting channel formed by pumping out the grouting hose after grouting the arc-shaped curing belt by the grouting hose, and filling the ultra-high performance cement grouting material of the composite fiber.

Optionally, the grouting hose adopts 3-10 mm steel spring as supporting framework, wraps a layer of non-woven fabric filtering cloth layer outside, and then is externally connected with a layer of PE sleeve with thickness of 2-5 mm, the outermost layer is wrapped by nylon wire, and pipe section connectors are arranged at two ends of the grouting hose and are connected with steel lock buckles.

Optionally, the grouting hose is provided with a plurality of circular grout outlets in 1.4 times of the underground pipeline, four grout outlets are distributed on each cross section in the range, and the distance between each grout outlet is 100-150 mm; the grouting hose has three forms of a grouting port according to the volume shape of a grouting port channel, the grouting port channel is in an inverted ladder funnel shape within the range of 0.4 times of the diameter of an underground pipeline in the middle of the grouting hose, and the included angle of the grouting port is 97 degrees and 67 degrees; in the diameter range of 0.4-0.9 times of the underground pipeline, the pulp outlet channel is cylindrical with the same size of the upper and lower cross section areas, and the included angle of the pulp outlet is 105 degrees and 75 degrees; in the diameter range of 0.9-1.4 times of the underground pipeline, the pulp outlet channel is in an inverted cone shape with a small upper part and a large lower part. The included angles of the pulp outlets are 111 degrees and 81 degrees.

The embodiment of the application also provides a construction method of the double-ring hoop-shaped grouting reinforcement structure for the tunnel to penetrate through the existing pipeline, which comprises the following steps:

step S1, surveying a field around a grouting site, and determining surrounding stratum geological conditions, buried depth of existing pipelines, horizontal positions of pipeline axes, pipe tunneling distances, tunnel excavation diameters and directions of the pipelines and tunnels in a grouting range;

s2, performing site leveling, namely designing an engineering drawing of a semicircular grouting channel below the bottom of the pipeline according to the embedded depth position of the existing pipeline and the excavation diameter of the tunnel, calculating the length and depth to be drilled by a drilling machine, determining a drilling track by using a directional drilling device, designing a line channel, and determining a grouting end and a grouting end of the semicircular grouting channel according to the line channel;

s3, starting the drilling machine, excavating a semicircular channel by a drill bit, and simultaneously, pulling a grouting hose to enter from a grouting end and exit from a grouting end, so that the semicircular grouting hose with quincuncial grouting ports is arranged in the bottom range of the pipeline, and the grouting ports are only arranged in the diameter range of the pipeline;

s4, performing semicircular grouting at a grouting end and a grouting end by using a grouting pump to form an arc-shaped curing belt at the bottom of the pipeline;

step S5: after the grouting body has certain strength, the semicircular grouting hose is pulled out, and the semicircular grouting channel is filled with cement slurry to form a grouting isolation belt;

step S6: after the bottom arc-shaped curing belt and the grouting isolation belt below the bottom of the pipeline are completed, drilling a plurality of vertical grouting channels which are arranged side by utilizing a drilling machine 5 in a diameter range of about 1.2 times of the pipeline, wherein the arrangement direction of one row of grouting channels is vertical to the pipeline axis, the drilling depth of the grouting channels is increased along with the increase of the excavation central axis of the pipeline, the grouting channels are symmetrically distributed about the pipeline central axis, and the tail ends of the grouting channels form a semicircular surrounding form above the pipeline;

step S7: vertical grouting guide pipes with grouting holes at the tail ends are inserted into the grouting channels for simultaneous grouting, the grouting outlets are uniformly arranged along the circumference of the guide pipes, three grouting holes are arranged at each section to form a semicircular grouting reinforcement area, and a double-ring hoop grouting reinforcement area is integrally formed with semicircular grouting below the bottom of the pipeline;

step S8: repeating the steps S2-S7, carrying out annular grouting reinforcement with unequal intervals of each ring at the position of the pipeline within the range of double tunnel excavation diameter, wherein the grouting interval of each ring of the pipeline is 400-500 mm within the range of tunnel excavation diameter; in the range of 1-2 times tunnel excavation diameter, the grouting interval of each ring is 1000mm;

step S9: and (3) extracting and cleaning all vertical grouting guide pipes and grouting hoses, filling and compacting all grouting channels, a grouting end and a grouting end, disassembling equipment, and cleaning a construction site.

The beneficial effects of the application are as follows:

1. the composite fiber superhigh-performance cement grouting material mixed with cement in building industry, industrial waste, etc. is one cement grouting material with high strength, high adhesion and low porosity, and has obviously raised soil strength and compression modulus and relatively high water stopping, filling and supporting functions.

2. By adopting the construction method provided by the application, the lower semicircular grouting and the upper semicircular grouting are carried out on the pipeline, the hoop grouting is integrally formed, and the hoop grouting is carried out on soil around the pipeline in the main disturbance range of tunnel excavation, so that the pipeline is restrained by the surrounding soil under the action of the hoop, the bending rigidity is increased, the pipeline settlement amount is reduced, the damage of the pipeline caused by the cracking, the damage and the like caused by the settlement is effectively reduced, the risk of pipeline leakage at the reinforced part is reduced, the pipeline safety control of the pipeline penetrating through the existing pipeline under the tunnel construction is effectively improved, the risk problem existing in the tunnel construction is reduced, and the future existing pipeline maintenance cost is reduced.

3. According to the application, by adopting a micro-disturbance non-excavation grouting reinforcement technology, the soil body covered on the underground pipeline is not required to be excavated integrally, and the pipeline reinforcement cost is greatly saved; the method is extremely suitable for urban areas with dense population and unmanned areas with complex terrains, has little influence on natural landscapes such as surrounding stratum landforms, vegetation landscapes and the like, has a certain environmental protection effect, and is particularly suitable for reinforcement construction of key engineering pipelines of underground large-diameter overlength pipelines under other construction disturbance.

4. The micro-disturbance non-excavation reinforcement technology adopted by the application has the advantages of simpler operation, higher construction speed, small disturbance to stratum, lower investment cost and reinforcement cost and remarkable social and economic benefits.

Drawings

For a clearer description of the technical solutions of the embodiments of the present application, the drawings that are needed in the description of the embodiments will be briefly introduced below, it being obvious that the drawings in the description below are only some embodiments of the present application, and that other drawings can be obtained according to these drawings without inventive effort for a person skilled in the art, wherein:

fig. 1 is a schematic diagram of excavation of a semicircular grouting channel at the bottom of a pipeline penetrating through an existing pipeline under a tunnel and layout of grouting hoses, which are provided by the embodiment of the application;

FIG. 2 is a schematic diagram of a semicircular grouting reinforcement area and an annular reinforcement zone area at the bottom of a pipeline penetrating through an existing pipeline under a tunnel according to an embodiment of the present application;

FIG. 3 is a schematic diagram of a dual-ring grouting reinforcement technology for a tunnel to penetrate through an existing pipeline and an implementation method thereof according to an embodiment of the present application;

FIG. 4 is a schematic diagram of a pipe bottom semicircular grouting hose device for a tunnel to pass through an existing pipeline according to an embodiment of the present application

FIGS. 5 (a) - (c) are schematic diagrams of a cross section and a grout outlet structure of a grouting hose at the bottom of a tunnel penetrating through an existing pipeline according to an embodiment of the present application;

FIG. 6 is a schematic diagram of a vertical grouting guide pipe device for performing semicircular grouting reinforcement above a pipeline penetrating through an existing pipeline under a tunnel, which is provided by the embodiment of the application;

FIG. 7 is a schematic diagram of a cross-sectional structure and a grouting outlet of a grouting conduit above a pipeline penetrating an existing pipeline under a tunnel according to an embodiment of the present application;

FIG. 8 is a schematic diagram of a grouting pipe connection device for synchronously performing semicircular grouting above a pipeline penetrating through an existing pipeline under a tunnel, which is provided by the embodiment of the application;

fig. 9 is a schematic diagram of grouting effect after hoop grouting reinforcement performed on a pipeline penetrating through an existing pipeline under a tunnel according to an embodiment of the present application.

Detailed Description

The following description of the embodiments of the present application will be made clearly and fully with reference to the accompanying drawings, in which it is evident that the embodiments described are some, but not all embodiments of the application. All other embodiments, which can be made by those skilled in the art based on the embodiments of the application without making any inventive effort, are intended to be within the scope of the application.

The terms first, second and the like in the description and in the claims, are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order. It is to be understood that the data so used may be interchanged, as appropriate, such that embodiments of the present application may be implemented in sequences other than those illustrated or described herein, and that the objects identified by "first," "second," etc. are generally of a type, and are not limited to the number of objects, such as the first object may be one or more. Furthermore, in the description and claims, "and/or" means at least one of the connected objects, and the character "/", generally means that the associated object is an "or" relationship.

The double-ring hoop grouting reinforcement structure for the tunnel underpass existing pipeline and the construction method thereof provided by the embodiment of the application are described in detail through specific embodiments and application scenes thereof by combining the accompanying drawings.

Referring to fig. 1 to 8, an embodiment of the present application provides a dual-hoop grouting reinforcement structure for a tunnel to be penetrated with an existing pipeline, which includes a dual-hoop grouting reinforcement area 29, including an arc-shaped curing zone 23 located below a pipeline, a semicircular grouting reinforcement area 25 connected with the arc-shaped curing zone 23 and wrapping the pipeline, and a grouting isolation belt 24 arranged to semi-surround the pipeline, wherein the grouting isolation belt 24 is formed by grouting and filling composite fiber ultra-high performance cement grouting material in a semicircular grouting channel therein.

Specifically, the composite fiber ultra-high performance cement grouting material comprises, by weight, 290-310 parts of 42.5-grade ordinary Portland cement slurry, 15 parts of water glass, 20 parts of primary fly ash, 15 parts of S75-grade slag, 43 parts of secondary silica fume, 3 parts of naphthalene sulfonate water reducer, 38 parts of complex recycled fibers and 100-120 parts of water.

The water-cement ratio of the 42.5-grade ordinary Portland cement slurry is 0.4-0.6; the seepage rate of cement slurry is not more than 3-8%; the naphthalene sulfonate water reducer is a high-performance water reducer with the water reducing rate of 18-25%.

The complex recovery fiber comprises common steel fiber and waste tire recovery steel fiber, the length-diameter ratio is 45-50, and the length is 3mm, 5mm and 7mm according to the following ratio of 4:2:1 by mass ratio.

The arc-shaped curing belt 23 is formed by grouting by a grouting pump 22 through a grouting hose 6 provided with a grouting outlet 13 in a semicircular grouting channel drilled by a grouting channel drilling machine device formed by a drilling machine drill bit 3, a drilling machine control wire 4 and a drilling machine central control system acquisition vehicle 5.

It should be further noted that the grouting channel drilling rig device is arranged above the pipeline beside the surface slurry outlet end 1 and the slurry inlet end 2.

The grouting isolation belt 24 is formed by grouting in a semicircular grouting channel formed by the grouting hose 6 after grouting the arc-shaped curing belt 23 by the grouting hose 6, and filling the ultra-high performance cement grouting material of the composite fiber.

The grouting hose 6 adopts a steel spring with the thickness of 3-10 mm as a supporting framework 7, a layer of non-woven fabric filter cloth layer 8 is wrapped outside, a PE sleeve 9 with the thickness of 2-5 mm is further externally connected, the outermost layer is wrapped by a nylon wire mesh 10, and pipe section connectors 11 are arranged at two ends of the grouting hose 6 and are connected with steel lock buckles 12.

Four grout outlets 13 are distributed on each cross section of the grouting hose 6, the grout outlets of the grouting hose 6 are in three forms according to the volume shape of the grout outlet channels, and the grout outlet channels are of inverted trapezoid funnel shapes within the range of 0.4 times of the diameter of the underground pipeline in the middle of the grouting hose, and the included angles of the grout outlets are 97 degrees and 67 degrees; in the diameter range of 0.4-0.9 times of the underground pipeline, the pulp outlet channel is cylindrical with the same size of the upper and lower cross section areas, and the included angle of the pulp outlet is 105 degrees and 75 degrees; in the diameter range of 0.9-1.4 times of the underground pipeline, the pulp outlet channel is in an inverted cone shape with a small upper part and a large lower part. The included angles of the pulp outlets are 111 degrees and 81 degrees. The setting range of the grouting hose outlet is about 1.4 times of the diameter range of the underground ultra-long pipeline.

The semicircular grouting reinforcement zone 25 is formed by grouting around the pipe by the drilling machine 5, the grouting pipe connecting device 17 and the vertical grouting pipe 14.

The grouting pipe connecting device 17 is formed by connecting 1 cross-shaped grouting main pipe 18, 5 vertical grouting connecting pipes 19, 2L-shaped grouting connecting pipes 20, 4 pipe connecting tee joints 26 and a plurality of grouting sleeves 21 through threads.

The vertical grouting guide pipe 14 is a steel grouting guide pipe with the diameter of 32mm, three grouting openings 15 are formed in the section of the same height of the guide pipe, the included angles of the grouting openings are 120 degrees, and grouting holes 16 are formed in the end part of the grouting guide pipe, so that grouting reinforcement of the grouting guide pipe in all directions is ensured.

One end of the double-ring hoop-shaped grouting reinforcement area 29 is communicated with a grouting end 2, and the other end is communicated with a grouting end 1; the depth of downward excavation of the slurry inlet end 2 and the slurry outlet end 1 is 25-100 cm under the average elevation of the flat field, and the length and the width of the excavation area are 6 times of the diameter of the semicircular grouting channel of the double-ring hoop-shaped grouting reinforcement area 29 respectively.

Referring to fig. 1-3 and fig. 9, the embodiment of the application further provides a construction method of a double-annular grouting reinforcement structure for a tunnel to penetrate through an existing pipeline, comprising the following steps:

step S1, surveying a field around a grouting site, and determining surrounding stratum geological conditions, buried depth of existing pipelines, horizontal positions of pipeline axes, pipe tunneling distances, tunnel excavation diameters and directions of the pipelines and tunnels in a grouting range;

before step S1, the method further includes the steps of: the working conditions of the existing underground ultra-long pipeline are strictly investigated, and the disturbance influence of pipeline axis distribution, pipeline diameter, pipeline wall thickness, pipeline materials and structures near the pipeline on the pipeline is clear.

S2, performing site leveling, namely designing an engineering drawing of a semicircular grouting channel below the bottom of the pipeline according to the embedded depth position of the existing pipeline and the excavation diameter of the tunnel, calculating the length and depth to be drilled by a drilling machine, determining a drilling track by using a directional drilling device, designing a line channel, and determining a grouting end and a grouting end of the semicircular grouting channel according to the line channel;

it should be noted that, after determining the slurry inlet end 2 and the slurry outlet end 1 of the semicircular grouting channel, the slurry inlet end 2 and the slurry outlet end 1 with corresponding areas are drilled so as to ensure that the directional drilling machine performs positioning drilling.

S3, starting the drilling machine, excavating a semicircular channel by a drill bit, and simultaneously, pulling a grouting hose to enter from a grouting end and exit from a grouting end, so that the semicircular grouting hose with quincuncial grouting ports is arranged in the bottom range of the pipeline, and the grouting ports are only arranged in the diameter range of the pipeline;

after the drilling machine 5 enters the field, directional drilling construction is performed according to a designed route, and when the drilling machine bit 3 drills, the grouting hose 6 at the bottom of the pipeline is pulled into the semicircular grouting channel through the pipe section connector 11 and the steel lock catch 12.

S4, performing semicircular grouting at the grouting end 2 and the grouting end 1 by using a grouting pump to form an arc-shaped curing belt 23 at the bottom of the pipeline;

step S5: after the grouting body has certain strength, the semicircular grouting hose is pulled out, and the semicircular grouting channel is filled with cement slurry to form a grouting isolation belt;

specifically, after grouting the grouting hose 6, the grouting hose 6 is pulled out of the semicircular grouting channel by using the steel lock catch 12, grouting is performed at the grouting end 2 and the grouting end 1 by using the slurry pump 22, the drilled grouting channel is filled with cement slurry, and after the cement slurry is solidified, the grouting isolation belt 24 is formed.

Step S6: after the bottom arc-shaped curing belt 23 and the grouting isolation belt 24 below the bottom of the pipeline are completed, drilling a plurality of vertical grouting channels which are arranged side by utilizing a drilling machine 5 in a diameter range of about 1.2 times of the pipeline, wherein the arrangement direction of one row of grouting channels is vertical to the pipeline axis, the drilling depth of the grouting channels increases along with the increase of the excavation central axis of the pipeline, the grouting channels are symmetrically distributed about the pipeline central axis, and the tail ends of the grouting channels form a semicircular surrounding mode above the pipeline;

step S7: vertical grouting guide pipes with grouting holes at the tail ends are inserted into the grouting channels for simultaneous grouting, the grouting outlets are uniformly arranged along the circumference of the guide pipes, three grouting holes 15 are arranged at each section to form a semicircular grouting reinforcement area 25, and a double-ring hoop-shaped grouting reinforcement area 29 is integrally formed with semicircular grouting below the bottom of the pipeline;

step S8: repeating the steps S2-S7, carrying out annular grouting reinforcement with unequal intervals of each ring at the position of the pipeline within the range of double tunnel excavation diameter, and grouting 27 intervals of 400-500 mm in each ring of the pipeline within the range of tunnel excavation diameter; in the range of 1-2 times tunnel excavation diameter, the interval between grouting 28 rings is 1000mm;

step S9: all vertical grouting pipes 14 and grouting hoses 6 are extracted and cleaned, all grouting channels, a grouting end 2 and a grouting end 1 are filled with soil and compacted, equipment is disassembled, and a construction site is cleaned.

The beneficial effects of the application are as follows:

1. the composite fiber superhigh-performance cement grouting material mixed with cement in building industry, industrial waste, etc. is one cement grouting material with high strength, high adhesion and low porosity, and has obviously raised soil strength and compression modulus and relatively high water stopping, filling and supporting functions.

2. By adopting the construction method provided by the application, the lower semicircular grouting and the upper semicircular grouting are carried out on the pipeline, the hoop grouting is integrally formed, and the hoop grouting is carried out on soil around the pipeline in the main disturbance range of tunnel excavation, so that the pipeline is restrained by the surrounding soil under the action of the hoop, the bending rigidity is increased, the pipeline settlement amount is reduced, the damage of the pipeline caused by the cracking, the damage and the like caused by the settlement is effectively reduced, the risk of pipeline leakage at the reinforced part is reduced, the pipeline safety control of the pipeline penetrating through the existing pipeline under the tunnel construction is effectively improved, the risk problem existing in the tunnel construction is reduced, and the future existing pipeline maintenance cost is reduced.

3. According to the application, by adopting a micro-disturbance non-excavation grouting reinforcement technology, the soil body covered on the underground pipeline is not required to be excavated integrally, and the pipeline reinforcement cost is greatly saved; the method is extremely suitable for urban areas with dense population and unmanned areas with complex terrains, has little influence on natural landscapes such as surrounding stratum landforms, vegetation landscapes and the like, has a certain environmental protection effect, and is particularly suitable for reinforcement construction of key engineering pipelines of underground large-diameter overlength pipelines under other construction disturbance.

4. The micro-disturbance non-excavation reinforcement technology adopted by the application has the advantages of simpler operation, higher construction speed, small disturbance to stratum, lower investment cost and reinforcement cost and remarkable social and economic benefits.

It should be noted that, in this document, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one … …" does not exclude the presence of other like elements in a process, method, article, or apparatus that comprises the element.

Furthermore, it should be noted that the scope of the methods and systems in the embodiments of the present application is not limited to performing the functions in the order shown or discussed, but may also include performing the functions in a substantially simultaneous manner or in an opposite order depending on the functions involved, e.g., the described methods may be performed in an order different from that described, and various steps may also be added, omitted, or combined. Additionally, features described with reference to certain examples may be combined in other examples.

The embodiments of the present application have been described above with reference to the accompanying drawings, but the present application is not limited to the above-described embodiments, which are merely illustrative and not restrictive, and many forms may be made by those having ordinary skill in the art without departing from the spirit of the present application and the scope of the claims, which are to be protected by the present application.

Claims (10)

1. The utility model provides a double-ring hoop shape slip casting reinforced structure of existing pipeline is worn under tunnel which characterized in that includes:

the double-hoop grouting reinforcement area (29) comprises an arc-shaped solidification area (23) positioned below a pipeline, a semicircular grouting reinforcement area (25) connected with the arc-shaped solidification area (23) and wrapping the pipeline, and a grouting isolation area (24) arranged to semi-surround the pipeline, wherein the grouting isolation area (24) is formed by grouting and filling composite fiber ultrahigh-performance cement grouting material in a semicircular grouting channel in the grouting isolation area.

2. The double-ring hoop grouting reinforcement structure of a tunnel underpass existing pipeline according to claim 1, wherein the composite fiber ultra-high performance cement grouting material comprises, by weight, 290-310 parts of 42.5 grade ordinary Portland cement slurry, 15 parts of water glass, 20 parts of primary fly ash, 15 parts of S75 grade slag, 43 parts of secondary silica fume, 3 parts of naphthalene sulfonate water reducer, 38 parts of complex recycled fiber and 100-120 parts of water.

3. The dual-ring hoop-shaped grouting reinforcement structure for a tunnel underpass existing pipeline according to claim 2, wherein the cement ratio of the 42.5-grade ordinary portland cement slurry is 0.4-0.6; the seepage rate of cement slurry is not more than 3-8%; the naphthalene sulfonate water reducer is a high-performance water reducer with the water reducing rate of 18-25%.

4. The double-annular grouting reinforcement structure for a tunnel underpass existing pipeline according to claim 2 or 3, wherein the complex recycled fiber comprises common steel fiber and junked tire recycled steel fiber, the length-diameter ratio is 45-50, and the length is 3mm, 5mm and 7mm of three steel fibers are as follows: 2:1 by mass ratio.

5. The double-ring-shaped grouting reinforcement structure for a tunnel underpass existing pipeline according to claim 1, wherein one end of the double-ring-shaped grouting reinforcement area (29) is communicated with a grouting end (2), and the other end is communicated with a grouting end (1); the depth of excavation downwards of the slurry inlet end (2) and the slurry outlet end (1) is 25-100 cm under the average elevation of the flat field, and the length and the width of the excavation area are respectively 6 times of the diameter of a semicircular grouting channel of the double-ring hoop-shaped grouting reinforcement area (29).

6. The dual-hoop-shaped grouting reinforcement structure for a tunnel underpass existing pipeline according to claim 1, wherein the semicircular grouting reinforcement area (25) is formed by grouting around the pipeline through a drilling machine (5), a grouting pipe connection device (17) and a vertical grouting pipe (14); the grouting guide pipe connecting device (17) is formed by connecting 1 cross-shaped grouting main pipe (18), 5 vertical grouting connecting pipes (19), 2L-shaped grouting connecting pipes (20), 4 pipeline connecting tee joints (26) and a plurality of grouting sleeves (21) through threads; the vertical grouting guide pipe (14) is a steel grouting guide pipe with the diameter of 32mm, three grouting openings (15) are formed in the section of the same height of the guide pipe, the included angles of the grouting openings are 120 degrees, and grouting holes (16) are formed in the end part of the grouting guide pipe, so that grouting reinforcement of the grouting guide pipe in all directions is ensured.

7. The double-ring hoop-shaped grouting reinforcement structure for the tunnel underpass existing pipelines according to claim 1, wherein the arc-shaped curing belt (23) is formed by grouting a grouting pump (22) through a grouting hose (6) provided with a grouting outlet (13) in a semicircular grouting channel drilled by matching a drill bit (3), a drill control wire (4) and a drill central control system acquisition vehicle (5); the grouting isolation belt (24) is formed by grouting in a semicircular grouting channel formed by the grouting hose (6) after grouting the arc-shaped curing belt (23) by the grouting hose (6) and filling the ultra-high performance cement grouting material of the composite fiber.

8. The double-ring hoop-shaped grouting reinforcement structure for the tunnel underpass existing pipeline according to claim 7, wherein the grouting hose (6) adopts a 3-10 mm steel spring as a supporting framework (7), a layer of non-woven fabric filter cloth layer (8) is wrapped outside, a layer of PE sleeve (9) with the thickness of 2-5 mm is further wrapped outside, the outermost layer is wrapped by a nylon wire mesh (10), and pipe section connectors (11) are arranged at two ends of the grouting hose and are connected with a steel lock catch (12).

9. The double-ring hoop-shaped grouting reinforcement structure for a tunnel underpass existing pipeline according to claim 8, wherein the grouting hose is provided with a plurality of circular grout outlets within 1.4 times of an underground pipeline, four grout outlets (13) are distributed on each cross section within the range, and the distance between each grout outlet is 100-150 mm; the grouting hose has three forms of a grouting port according to the volume shape of a grouting port channel, the grouting port channel is in an inverted ladder funnel shape within the range of 0.4 times of the diameter of an underground pipeline in the middle of the grouting hose, and the included angle of the grouting port is 97 degrees and 67 degrees; in the diameter range of 0.4-0.9 times of the underground pipeline, the pulp outlet channel is cylindrical with the same size of the upper and lower cross section areas, and the included angle of the pulp outlet is 105 degrees and 75 degrees; in the diameter range of 0.9-1.4 times of the underground pipeline, the pulp outlet channel is in an inverted cone shape with a small upper part and a large lower part. The included angles of the pulp outlets are 111 degrees and 81 degrees.

10. A method of constructing a double-loop grouting reinforcement structure for a down-going existing pipeline of a tunnel as claimed in any one of claims 1 to 9, comprising:

step S1, surveying a field around a grouting site, and determining surrounding stratum geological conditions, buried depth of existing pipelines, horizontal positions of pipeline axes, pipe tunneling distances, tunnel excavation diameters and directions of the pipelines and tunnels in a grouting range;

s2, performing site leveling, namely designing an engineering drawing of a semicircular grouting channel below the bottom of the pipeline according to the embedded depth position of the existing pipeline and the excavation diameter of the tunnel, calculating the length and depth to be drilled by a drilling machine, determining a drilling track by using a directional drilling device, designing a line channel, and determining a grouting end and a grouting end of the semicircular grouting channel according to the line channel;

s3, starting the drilling machine, excavating a semicircular channel by a drill bit, and simultaneously, pulling a grouting hose to enter from a grouting end and exit from a grouting end, so that the semicircular grouting hose with quincuncial grouting ports is arranged in the bottom range of the pipeline, and the grouting ports are only arranged in the diameter range of the pipeline;

s4, performing semicircular grouting at a grouting end and a grouting end by using a grouting pump to form an arc-shaped curing belt at the bottom of the pipeline;

step S5: after the grouting body has certain strength, the semicircular grouting hose is pulled out, and the semicircular grouting channel is filled with cement slurry to form a grouting isolation belt;

step S6: after the bottom arc-shaped curing belt and the grouting isolation belt below the bottom of the pipeline are completed, drilling a plurality of vertical grouting channels which are arranged side by utilizing a drilling machine 5 in a diameter range of about 1.2 times of the pipeline, wherein the arrangement direction of one row of grouting channels is vertical to the pipeline axis, the drilling depth of the grouting channels is increased along with the increase of the excavation central axis of the pipeline, the grouting channels are symmetrically distributed about the pipeline central axis, and the tail ends of the grouting channels form a semicircular surrounding form above the pipeline;

step S7: vertical grouting guide pipes with grouting holes at the tail ends are inserted into the grouting channels for simultaneous grouting, the grouting outlets are uniformly arranged along the circumference of the guide pipes, three grouting holes are arranged at each section to form a semicircular grouting reinforcement area, and a double-ring hoop grouting reinforcement area is integrally formed with semicircular grouting below the bottom of the pipeline;

step S8: repeating the steps S2-S7, carrying out annular grouting reinforcement with unequal intervals of each ring at the position of the pipeline within the range of double tunnel excavation diameter, wherein the grouting interval of each ring of the pipeline is 400-500 mm within the range of tunnel excavation diameter; in the range of 1-2 times tunnel excavation diameter, the grouting interval of each ring is 1000mm;

step S9: and (3) extracting and cleaning all vertical grouting guide pipes and grouting hoses, filling and compacting all grouting channels, a grouting end and a grouting end, disassembling equipment, and cleaning a construction site.