WO2020248596A1 - Protection structure for preventing ground heave caused by tunnel grouting reinforcement and grouting method - Google Patents

Protection structure for preventing ground heave caused by tunnel grouting reinforcement and grouting method Download PDF

Info

Publication number
WO2020248596A1
WO2020248596A1 PCT/CN2020/070390 CN2020070390W WO2020248596A1 WO 2020248596 A1 WO2020248596 A1 WO 2020248596A1 CN 2020070390 W CN2020070390 W CN 2020070390W WO 2020248596 A1 WO2020248596 A1 WO 2020248596A1
Authority
WO
WIPO (PCT)
Prior art keywords
grouting
arch
tunnel
reverse
curved arch
Prior art date
Application number
PCT/CN2020/070390
Other languages
French (fr)
Chinese (zh)
Inventor
王树仁
张纪云
李春柳
龚健
王新宇
许来斌
Original Assignee
河南理工大学
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 河南理工大学 filed Critical 河南理工大学
Publication of WO2020248596A1 publication Critical patent/WO2020248596A1/en

Links

Images

Classifications

    • E—FIXED CONSTRUCTIONS
    • E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
    • E02D—FOUNDATIONS; EXCAVATIONS; EMBANKMENTS; UNDERGROUND OR UNDERWATER STRUCTURES
    • E02D3/00—Improving or preserving soil or rock, e.g. preserving permafrost soil
    • E02D3/12—Consolidating by placing solidifying or pore-filling substances in the soil
    • E—FIXED CONSTRUCTIONS
    • E21—EARTH OR ROCK DRILLING; MINING
    • E21D—SHAFTS; TUNNELS; GALLERIES; LARGE UNDERGROUND CHAMBERS
    • E21D11/00—Lining tunnels, galleries or other underground cavities, e.g. large underground chambers; Linings therefor; Making such linings in situ, e.g. by assembling
    • E21D11/003—Linings or provisions thereon, specially adapted for traffic tunnels, e.g. with built-in cleaning devices
    • E—FIXED CONSTRUCTIONS
    • E21—EARTH OR ROCK DRILLING; MINING
    • E21D—SHAFTS; TUNNELS; GALLERIES; LARGE UNDERGROUND CHAMBERS
    • E21D11/00—Lining tunnels, galleries or other underground cavities, e.g. large underground chambers; Linings therefor; Making such linings in situ, e.g. by assembling
    • E21D11/04—Lining with building materials
    • E21D11/10—Lining with building materials with concrete cast in situ; Shuttering also lost shutterings, e.g. made of blocks, of metal plates or other equipment adapted therefor
    • E—FIXED CONSTRUCTIONS
    • E21—EARTH OR ROCK DRILLING; MINING
    • E21D—SHAFTS; TUNNELS; GALLERIES; LARGE UNDERGROUND CHAMBERS
    • E21D11/00—Lining tunnels, galleries or other underground cavities, e.g. large underground chambers; Linings therefor; Making such linings in situ, e.g. by assembling
    • E21D11/14—Lining predominantly with metal
    • E21D11/15—Plate linings; Laggings, i.e. linings designed for holding back formation material or for transmitting the load to main supporting members
    • E21D11/152—Laggings made of grids or nettings
    • E—FIXED CONSTRUCTIONS
    • E21—EARTH OR ROCK DRILLING; MINING
    • E21D—SHAFTS; TUNNELS; GALLERIES; LARGE UNDERGROUND CHAMBERS
    • E21D11/00—Lining tunnels, galleries or other underground cavities, e.g. large underground chambers; Linings therefor; Making such linings in situ, e.g. by assembling
    • E21D11/14—Lining predominantly with metal
    • E21D11/18—Arch members ; Network made of arch members ; Ring elements; Polygon elements; Polygon elements inside arches
    • E—FIXED CONSTRUCTIONS
    • E21—EARTH OR ROCK DRILLING; MINING
    • E21D—SHAFTS; TUNNELS; GALLERIES; LARGE UNDERGROUND CHAMBERS
    • E21D20/00—Setting anchoring-bolts
    • E—FIXED CONSTRUCTIONS
    • E21—EARTH OR ROCK DRILLING; MINING
    • E21D—SHAFTS; TUNNELS; GALLERIES; LARGE UNDERGROUND CHAMBERS
    • E21D9/00—Tunnels or galleries, with or without linings; Methods or apparatus for making thereof; Layout of tunnels or galleries
    • E21D9/001—Improving soil or rock, e.g. by freezing; Injections
    • E—FIXED CONSTRUCTIONS
    • E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
    • E02D—FOUNDATIONS; EXCAVATIONS; EMBANKMENTS; UNDERGROUND OR UNDERWATER STRUCTURES
    • E02D2250/00—Production methods
    • E02D2250/003—Injection of material
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E10/00—Energy generation through renewable energy sources
    • Y02E10/20—Hydro energy

Definitions

  • subway projects have increasingly become the main direction of urban public transportation development.
  • the subway not only enhances the speed of travel and saves people's time, but also plays a good role in promoting the development of urban environmental protection.
  • Our country is in a period of accelerating industrialization and urbanization. Millions of people are flooding into big cities, putting tremendous pressure on urban management and urban transportation.
  • the subway project is a large-scale civil engineering with large investment, long construction period and complex technology.
  • the subway project has the characteristics of concealment, the uncertainty of the geological environment, and the complexity of construction technology, which will inevitably lead to a large number of risks during the construction period, complex types, and even greater economic losses after an accident.
  • the grout diffusion radius is generally about 25cm, so in actual construction, the grouting hole spacing is usually designed to be about 50cm to ensure that under effective grouting pressure, the grout diffusion radius of the two grouting holes overlaps. , It has been achieved that the rock and soil between the grouting holes are fully reinforced.
  • the object of the present invention is to provide a protective structure and a grouting method for preventing the grouting reinforcement of the tunnel from causing the ground surface uplift, so as to solve the above-mentioned problems in the prior art and effectively prevent the grouting reinforcement from causing the ground surface uplift.
  • the supporting structure is an anchor rod hanging on the inner wall of the tunnel body, or a steel arch support or a combined support composed of the above two.
  • the thickness of the reverse arch is 3-4 m, and the thickness of the forward arch is greater than 2 m.
  • the vertical centerline of the tunnel body, the vertical centerline of the forward curved arch, and the vertical centerline of the reverse curved arch are collinear.
  • an advanced grouting pipe arranged obliquely toward the direction of the tunnel is provided on the top of the inner contour of the tunnel body, and the outlet of the advanced grouting pipe is located in the coverage area of the forward curved arch and the reverse curved arch between.
  • a tunnel advance grouting method based on the above-mentioned protective structure for preventing the tunnel grouting reinforcement from causing ground uplift including the following steps:
  • Surface drilling and grouting before the tunnel is constructed to the area to be protected, along the direction of the tunnel body, perform surface drilling on the surface of the stratum with loose rock and soil directly above its direction.
  • the surface drilling is arranged in a plum blossom shape, in the same row
  • the top-view center line of the surface boreholes is perpendicular to the tunnel direction.
  • the borehole at the center has the largest depth, and the depth of the boreholes decreases from the center to both sides, and the lower ends of the surface boreholes in the same row are located on the section In the design of reverse arch range; place a repeatable grouting pipe into the surface borehole, and perform the grouting operation through the repeatable grouting pipe, so that the grout and the loose rock and soil form an integral supporting structure, which together form a reverse Arch towards
  • Tunnel support when the tunnel is constructed to the area to be protected, first dig out the rough section of the tunnel body, first spray concrete and install the supporting structure, and finally re-spray concrete;
  • the designed inverted arch is located in the loose rock and soil layer directly above the tunnel direction, the designed inverted arch is a downward convex arch, and the inverted arch is on the horizontal ground along the width direction.
  • the distance between the lower end of the repeatable grouting pipe and the lower end surface of the designed reverse arch is equal.
  • the grouting operation in step A is: the lower end of the repeatable grouting pipe is no more than 10 cm from the bottom of the borehole, initial grouting is performed first, and solidified slurry is injected into the grouting hole through the repeatable grouting pipe.
  • the grout adopts filling grouting, and the grouting pressure is controlled to be less than 0.5Mpa.
  • the grouting liquid used is composed of 325# cement, additives, and water, and the ratio is 1:0.08:2; after the initial grouting is completed 2-3h, the grout reaches In the initial setting state, the grout is initially bonded to the loose rock and sand in the loose rock and soil to form a whole. After it has a certain bearing strength, the second grouting is carried out.
  • the grouting pressure of the second grouting is greater than that of the initial grouting
  • the grouting pressure is controlled to be less than 3Mpa, and the backward segmented grouting is used.
  • the grouting fluid used is composed of 325# cement, additives and water, and the ratio is 1:0.08:2.
  • the backward segmented grouting thickness is adopted. The length is 3-4m, until a complete reverse arch is formed to increase the strength of the loose rock and soil layer.
  • the internal grouting and solidification are formed through the initial grouting and secondary grouting, and the internal grouting is solidified and the surrounding loose rock
  • the soil layer forms an integral supporting structure together to form a reverse arch for stress bearing.
  • the protective structure and grouting method for preventing the surface uplift caused by the grouting reinforcement of the tunnel utilizes the space stability theory of the curved arch and the conventional anchor and shotcrete support, steel arch frame plus shotcrete anchor support or combined support and other passive supports
  • the protection forms are organically combined, and the stress-bearing body is formed by layering, multiple grouting and combined with multiple passive support methods, forming a reverse curved arch and a forward curved arch structure successively, changing the loose rock formations around the tunnel (lane),
  • the stress distribution state of loose rock and soil layers such as sandy soil layer shifts the peak of stress concentration out of the three-zone stress area of the tunnel (roadway), and makes full use of the characteristic of large bearing capacity of the curved arch shape, which isolates the surface of the stratum.
  • the grouting not only controls the deformation of the ground and the structures on the stratum surface, prevents the uplift of the ground surface, but also fully realizes the effect of grouting reinforcement on the loose rock and soil layer.
  • the strength and stiffness of the loose rock and soil are repaired by high-pressure grouting, which improves the integrity and bearing capacity of the surrounding rock, and makes the loose rock and soil on the upper part of the tunnel (lane) stay in a good stable state for a long time, so that the When the surrounding environment and geotechnical properties are not very accurate, high-pressure grouting is formed through the protection of the reverse arch.
  • the grouting method of the present invention has a wide range of applications and is suitable for both new excavation and repair of tunnels (lanes), especially for shallow tunnels (lanes) through loose rock and sand layers.
  • the present invention is easy to form a complete set
  • the construction technical measures of the project have the characteristics of simple method, easy implementation, convenient mechanized operation, and good supporting effect. They have the value of engineering promotion and application. With the continuous development of shallow underground projects, they have significant economic benefits.
  • Figure 1 is a schematic cross-sectional view of the overall arrangement of the present invention
  • Figure 2 is a schematic cross-sectional view of the arrangement of reverse curved arches in the present invention
  • Figure 3 is a schematic diagram of the layout of the advanced grouting reinforcement zone in the present invention.
  • Figure 4 is an overall plan view of the method for preventing ground uplift caused by grouting reinforcement in reverse continuous arching in the present invention
  • the purpose of the present invention is to provide a protective structure and a grouting method for preventing the grouting reinforcement of the tunnel from causing ground uplift, so as to solve the problems existing in the prior art.
  • This embodiment provides a protective structure for preventing the surface uplift caused by tunnel grouting reinforcement. As shown in Figs. 1-4, it includes a tunnel body 8 located below the stratum surface 1. The stratum directly above the tunnel body 8 is provided with ground The reverse curved arch 5 is formed by the slurry. The reverse curved arch 5 is a downwardly convex arch. The top edge of the inner contour of the tunnel body 8 is provided with a supporting structure, which surrounds the top edge of the inner contour of the tunnel body. The outer side of the protective structure is provided with a forward arch 11 formed by drilling and grouting. The forward arch 11 is an upward convex arch. The forward arch 11, the reverse arch 5 and the supporting structure are formed together Combination supporting structure to prevent the ground uplift caused by advanced grouting.
  • the supporting structure is an anchor rod, net-sprayed anchor support 13 or a steel arch support 16 or a combined support formed on the inner wall of the tunnel body 8.
  • the thickness of the reverse arch 5 is 3 to 4 m, and the thickness of the forward arch 11 is greater than 2 m.
  • the projection length of the reverse arch 5 on the horizontal ground along the width direction is L, as the span of the reverse arch, and the depth from the lowest point of the reverse arch 5 to the horizontal ground is H, as the vector height,
  • the vertical centerline 9 of the tunnel body 8 the vertical centerline of the forward curved arch 11, and the vertical centerline of the reverse curved arch 5 are collinear.
  • the inner contour of the tunnel body 8 is provided with an advanced grouting pipe 6 arranged obliquely toward the direction of the tunnel, and the outlet of the advanced grouting pipe 6 is located at the forward curved arch 11 and the reverse curved arch 5. Between coverage.
  • the advanced grouting pipe 6 can be arranged in accordance with the existing specifications. Generally, it is laid out according to the direction of the corresponding tunnel and inclined 30°-60°. The spacing is generally controlled at about 0.5m. The drilling angle and spacing can be adjusted appropriately in special geological conditions. , This technology is an existing technology. Specifically: drill a certain depth of grouting hole in the top of the tunnel (roadway) to install a grouting pipe for medium and deep hole grouting to form internal grouting and solidification, in the reverse continuous arch 5 and forward arch 11 Under the protection of, the grouting pressure of advanced grouting for medium and deep holes can be appropriately increased, generally controlled below 8Mpa.
  • the grouting liquid used is composed of 425# cement, additives, and water, and the ratio is 1:0.08:2.
  • the top edge of the inner contour of the tunnel body 8 is composed of an upper arc-shaped part and a lower vertical edge part connected to both ends of the arc-shaped part.
  • this embodiment also provides the above-mentioned advanced grouting method for tunnels to prevent ground uplift, including the following steps:
  • the temporary facilities that need to be relocated due to the construction of the stratum surface should be transferred, and the grouting station should be arranged at a suitable position to prepare for the subsequent reverse curved arch grouting.
  • Surface drilling 2 is carried out on the surface of the stratum with loose rock and soil layer 4 directly above its strike.
  • the diameter of the surface drilling should be slightly larger than the diameter of the grouting pipe.
  • the surface drilling is arranged in a plum blossom shape. The line is perpendicular to the direction of the tunnel.
  • the depth of the borehole at the center is the largest, and the depth of the boreholes decreases from the center to both sides, and the lower ends of the same row of boreholes are located within the design reverse arch range where the section is located ;
  • the spacing of the surface boreholes 2 is 0.4-0.6m;
  • the repeatable grouting pipe is made of a hard and flexible plastic pipe (PVC pipe).
  • PVC pipe hard and flexible plastic pipe
  • the bottom end of the repeatable grouting pipe is sealed, and the pipe wall is at intervals (such as 15- 20cm)
  • Drill a circle of grout holes, each circle is equidistant with a certain number of grout holes (such as 3-4), and the relative height of the grout holes on each repeatable grouting pipe is the same to make the grout It can spread evenly and equivalently around the grouting hole.
  • the grouting operation is carried out through the repeatable grouting pipe 3, so that the grout and the loose rock and soil layer 4 form an integral supporting structure, which together form a reverse arch 5;
  • the specific method is: when the tunnel is constructed to the area to be protected, first dig out the rough section 15 of the tunnel body, and immediately carry out the initial spraying of concrete.
  • the thickness of the initial spraying concrete is generally 20-30mm, and then according to the characteristics and strength grade of the surrounding rock and soil.
  • the excavated tunnel (lane) shall be supported by anchor rod hanging net and shotcrete anchor 13, steel arch support 16 or the combination of the two to form a supporting structure.
  • spray concrete with a thickness of 80-100mm.
  • the under-excavated parts should be manually treated, the over-excavated parts should be filled in, and the leaked anchor rods and anchor cable ends should be properly treated, and finally the entire tunnel (lane) should be leveled. To ensure that the shape and size of the entire tunnel (lane) section conform to the design.
  • the positive curved arch 11 formed by grouting around the top edge of the tunnel body contour
  • the specific method is: 1 day after the compound shotcrete is finished, drill a shallow grouting hole 7 with a depth of less than 2m on the top of the tunnel (lane), and then install a grouting pipe for grouting.
  • the grouting pressure is generally controlled below 5Mpa.
  • the grouting solution used is composed of 425# cement, additives, and water, and the ratio is 1:0.08:2. It forms a forward curved arch 11 around the top of the tunnel (lane), so that it and the supporting structure form a combined support ⁇ Protection structure.
  • the specific method is: drill a certain depth of grouting hole in the top of the tunnel (roadway) and install the advanced grouting pipe 6 for medium and deep hole grouting operations to form internal grouting and solidification.
  • the outlet of the advanced grouting pipe 6 is located at Between the coverage of the forward arch 11 and the reverse arch 5, under the protection of the reverse arch 5 and the forward arch 11, the grouting pressure of the medium and deep hole advanced grouting 6 can be appropriately increased, generally controlled at 8Mpa Below, the grouting fluid used is composed of 425# cement, additives, and water, and the ratio is 1:0.08:2.
  • the distance between the advanced grouting pipes is generally controlled at about 0.5m, and the grouting hole drilling can be adjusted appropriately in case of special geological conditions. Angle and spacing.
  • Concrete is poured on the bottom plate 10 of the tunnel to form a tunnel section size that meets the design requirements.
  • the designed inverted arch is located in the loose rock and soil layer 4 directly above the tunnel direction, and the designed inverted arch is a downwardly convex arch, and the inverted arch 5 is on the horizontal ground along the width direction.
  • the distance between the lower end of the repeatable grouting pipe 3 and the lower end surface of the designed reverse arch is equal.
  • Ground reverse continuous curved arch grouting belongs to surface grouting.
  • the drilling depth is generally 6-7m. The specific depth depends on the thickness of the loose rock and soil layer or the tunnel (lane) distance from the ground surface. Depends on the distance, and then according to the selected ⁇ K, L can be calculated;
  • the width of the structure to be protected is easy to measure, so L is easy to determine.
  • the grouting hole depth H can be calculated, but it must meet the requirements of forward curvature 11 and reverse curvature.
  • the distance between arches 5 is greater than the requirement of 2m.
  • the grouting operation in step A is:
  • the lower end of the repeatable grouting pipe is no more than 10cm away from the bottom of the borehole.
  • the initial grouting is performed first.
  • the solidified slurry is injected into the grouting hole through the repeatable grouting pipe.
  • the initial grouting adopts filling grouting, and the grouting pressure is controlled to be less than 0.5 Mpa (to prevent excessive grouting pressure from damaging the shape of the reverse arch 5 and affecting the bearing capacity of the overall loose rock and soil layer).
  • the grouting fluid used is composed of 325# cement, additives, and water, and the ratio is 1:0.08: 2.
  • the grouting pressure of the secondary grouting is greater than the grouting pressure of the first grouting and is controlled to be less than 3Mpa.
  • the backward segmented grouting is adopted.
  • the grouting liquid used is composed of 325# cement, additives and water, and the ratio is 1:0.08:2, adopt backward segmented grouting with a thickness of 3-4m, until a complete reverse arch 5 is formed, so as to improve the strength of the loose rock and soil layer.
  • the grouting should be washed with water Pipe, remove the remaining grout in the pipe, through the initial grouting and secondary grouting to form internal grouting and solids, the internal grouting and solids and the surrounding loose rock and soil layers form an integral supporting structure together to form a reverse curve for stress bearing Arch 5.
  • the backward segmented grouting is the prior art. Simply put, the grouting pipe is lifted for a certain distance after the first grouting is completed, such as 20-30cm, and then the second grouting is performed, and after the second grouting is completed, the grouting is performed again The pipe is raised 20-30cm for three grouting, and so on, until the grouting thickness reaches 3-4m.
  • the present invention uses the spatial stability theory of curved arches to organically combine passive support forms such as conventional bolting and shotcrete support, steel arches plus shotcrete anchor support, or combined support.
  • passive support forms such as conventional bolting and shotcrete support, steel arches plus shotcrete anchor support, or combined support.
  • Multiple grouting and a combination of multiple passive support methods jointly form a stress bearing body, which has successively formed a reverse curved arch and a forward curved arch structure, which changes the loose rock and sand layers around the tunnel (lane).
  • the stress distribution state shifts the peak of stress concentration out of the three-zone stress area of the tunnel (lane), making full use of the arch shape, which has the characteristics of large bearing capacity, and partitions the dynamic and static loads on the ground surface to the tunnel (lane) At the same time, it also isolates the influence of excessive grouting pressure in the tunnel (lane) on the surface roads and structures, respectively ensuring the mutual stability of the two, which can achieve high-pressure grouting, which not only controls the surface, ground, and The deformation of the structure prevents the uplift of the ground surface, and at the same time fully realizes the effect of grouting reinforcement of the loose rock and soil layer.
  • the strength and stiffness of the loose rock and soil are repaired by high-pressure grouting, which improves the integrity and bearing capacity of the surrounding rock, and makes the loose rock and soil on the upper part of the tunnel (lane) stay in a good stable state for a long time, so that the When the surrounding environment and geotechnical properties are not very accurate, high-pressure grouting is formed through the protection of the reverse arch.
  • the method of the present invention has a wide range of applications, and is suitable for both new excavation and repair of tunnels (lanes), and is especially suitable for projects where shallow tunnels (lanes) pass through loose rock and sand layers.
  • the present invention is easy to form a complete set of construction
  • Technical measures have the characteristics of simple method, easy implementation, convenient mechanized operation and good supporting effect, and have the value of engineering promotion and application. With the continuous development of shallow underground projects, they have significant economic benefits.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mining & Mineral Resources (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Structural Engineering (AREA)
  • General Life Sciences & Earth Sciences (AREA)
  • Geochemistry & Mineralogy (AREA)
  • Geology (AREA)
  • Civil Engineering (AREA)
  • Architecture (AREA)
  • Soil Sciences (AREA)
  • Environmental & Geological Engineering (AREA)
  • Agronomy & Crop Science (AREA)
  • Paleontology (AREA)
  • General Engineering & Computer Science (AREA)
  • Consolidation Of Soil By Introduction Of Solidifying Substances Into Soil (AREA)
  • Excavating Of Shafts Or Tunnels (AREA)
  • Lining And Supports For Tunnels (AREA)

Abstract

A protection structure for preventing ground heave caused by tunnel grouting reinforcement and a grouting method, relating to the technical field of geotechnical engineering, civil engineering and municipal engineering, and comprising a tunnel body (8) located below a stratum surface (1). A reverse curved arch (5) formed by ground surface grouting is arranged in the stratum directly above the tunnel body (8), and the reverse curved arch (5) is arched downwards; a support structure is arranged on a top slope of the inner contour of the tunnel body (8) and surrounds the top slope of the inner contour of the tunnel body (8); a forward curved arch (11) formed by drilling grouting is arranged on the outer side of the support structure, and the forward curved arch (11) is arched upwards. A stress bearing body is jointly formed by multi-layer multiple grouting and a combination of multiple passive supporting modes, the reverse curved arch (5) and the forward curved arch (11) are formed in sequence, and the stress distribution states of the loose rock stratum, and the sandy soil layer and the like surrounding the tunnel are changed. Therefore, high-pressure grouting can be formed by protection of the reverse curved arch (5) under the condition of being not familiar with the surrounding environment and the rock-soil property.

Description

防止隧道注浆加固引起地表***的防护结构及注浆方法Protective structure and grouting method for preventing ground uplift caused by tunnel grouting reinforcement 技术领域Technical field
本发明涉及岩土工程技术领域和土建市政技术领域，特别是涉及一种防止隧道注浆加固引起地表***的防护结构及注浆方法；适用于浅埋隧(巷)道穿越松散岩层、砂土层时超前注浆加固容易引起地表***、道路开裂、建筑物倾斜等一系列问题的永久性隧(巷)道工程。The invention relates to the technical field of geotechnical engineering and the technical field of civil engineering and municipal administration, in particular to a protective structure and a grouting method for preventing ground uplift caused by tunnel grouting reinforcement; suitable for shallow buried tunnels (lanes) to pass through loose rock layers and sand It is a permanent tunnel (road) project that can easily cause a series of problems such as surface uplift, road cracking, and building tilt.
背景技术Background technique
随着经济全球化的发展和城市化进程的加快，地铁工程越来越成为城市公共交通发展的主要方向。地铁不仅增强了出行的快捷性，节省了人们的时间，还为城市环保建设的开展起到了良好的促进作用。我国正处在工业化和城市化加速发展的时期，数以百万计的人口涌入大城市，给城市管理和城市交通带来巨大的压力。与其他工程相比，地铁工程是一项投资大、建设周期长、技术复杂的大型土木工程。地铁工程具有隐蔽性、地质环境的不确定性、施工技术复杂性等特点，这势必造成工程在施工期内的风险数量多、种类复杂，甚至出现事故后造成较大的经济损失。With the development of economic globalization and the acceleration of urbanization, subway projects have increasingly become the main direction of urban public transportation development. The subway not only enhances the speed of travel and saves people's time, but also plays a good role in promoting the development of urban environmental protection. Our country is in a period of accelerating industrialization and urbanization. Millions of people are flooding into big cities, putting tremendous pressure on urban management and urban transportation. Compared with other projects, the subway project is a large-scale civil engineering with large investment, long construction period and complex technology. The subway project has the characteristics of concealment, the uncertainty of the geological environment, and the complexity of construction technology, which will inevitably lead to a large number of risks during the construction period, complex types, and even greater economic losses after an accident.
地铁处于城市喧闹、人口密集、建构筑物密集的市区，为修建地铁而开挖的隧(巷)道位于整个地壳的浅部位置，需穿越松散岩层、砂土层时，这无疑增大了开挖和支护的难度。全国范围来看，地铁普遍建在地下20米左右深处，据统计北京、天津、广州、上海4个地铁城市，建造的隧(巷)道在地下20米左右，北京五号线深度达到24米。根据土壤、地质、线路分布不同，建造地铁深度也有差异，世界上有些国家如俄罗斯、伦敦等都是地下50米左右深度。The subway is located in a noisy, densely populated, and densely constructed urban area. The tunnel (lane) excavated for the construction of the subway is located in the shallow part of the entire crust. This is undoubtedly increased when it needs to pass through loose rock and sand layers. Difficulty of excavation and support. Nationwide, subways are generally built at a depth of about 20 meters underground. According to statistics, in Beijing, Tianjin, Guangzhou, and Shanghai, the tunnels (lanes) built are about 20 meters underground, and the depth of Beijing Line 5 reaches 24. Meter. Depending on the soil, geology, and line distribution, the depth of subway construction is also different. Some countries in the world, such as Russia and London, have a depth of about 50 meters underground.
针对隧(巷)道位于松散岩层、砂土层这种情况，且施工时会穿越松散岩土层、地面已有道路或其他建构筑物，目前一般隧(巷)道的施工只有极少部分端头部位采用明挖法，百分之九十的路线长度采用暗挖法中的钻爆法、盾构法、掘进机法、新奥法等方法。原本完成稳定的岩土层经历隧(巷)道的开挖必将改变原有的应力状态引起应力重新分布。上覆岩层及建构筑物的重量会引起隧(巷)道的变形，故必须对已开挖的隧(巷)道进行支护， 同时需要对隧(巷)道与地表间的松散岩层、砂土层进行加固，这段松散散岩层、砂土层称为埋深。目前对该部分岩土体加固基本上采用注浆的方法，由于隧(巷)道埋深较浅，相对于整个地层厚度来说是一个薄薄的壳体，隧(巷)道距地表较近为了达到注浆加固的效果，一般需要较大的注浆压力，但过大的注浆压力又会引起岩土体上拱直至地表发生***现象，破坏地表原有的状态、引起地表道路开裂、建构筑物不均匀沉降。此时若降低注浆压力，虽可以起到控制地表***变形的目的，但压力太低会直接导致浆液扩散半径的减小，以至于达不到加固岩土体的效果。根据经验得浆液扩散半径一般在25cm左右，故实际施工中通常将注浆钻孔间距设计为50cm左右，以保证在有效的注浆压力下，两个注浆孔的浆液扩散半径有交叉重合现象，已达到使注浆孔之间岩土体得到充分地加固。若注浆压力降低后，不但浆液的扩散半径会减小，常规的注浆孔间距根本无法保证周围岩土体得到充分加固，导致注浆体不连续，影响浆岩土混合体的受力状态，因此，其改进和创新势在必行。In view of the situation that the tunnel (lane) is located in the loose rock and sand layer, and the construction will pass through the loose rock and soil, there are roads or other structures on the ground, the current construction of general tunnels (lane) only has a very small part of the end The head part adopts the open excavation method, and 90% of the route length adopts the drilling and blasting method, the shield method, the roadheader method, and the new Austrian method in the undercut method. The excavation of the tunnel (lane) that was originally completed and stabilized will inevitably change the original stress state and cause the stress to redistribute. The weight of the overlying rock layer and the structure will cause the deformation of the tunnel (lane), so the excavated tunnel (lane) must be supported. At the same time, the loose rock layer and sand between the tunnel (lane) and the ground must be supported. The soil layer is reinforced, and this section of loose rock and sand is called the buried depth. At present, this part of the rock and soil is basically reinforced by grouting. Due to the shallow buried depth of the tunnel (lane), it is a thin shell relative to the thickness of the entire stratum. The tunnel (lane) is relatively far from the ground surface. In order to achieve the effect of grouting reinforcement, generally larger grouting pressure is required, but excessive grouting pressure will cause the rock and soil to arch up until the surface uplifts, destroy the original state of the surface, and cause surface road cracking , The uneven settlement of structures. At this time, if the grouting pressure is reduced, although it can achieve the purpose of controlling the surface uplift and deformation, too low pressure will directly cause the reduction of the grout diffusion radius, so that the effect of strengthening the rock and soil can not be achieved. According to experience, the grout diffusion radius is generally about 25cm, so in actual construction, the grouting hole spacing is usually designed to be about 50cm to ensure that under effective grouting pressure, the grout diffusion radius of the two grouting holes overlaps. , It has been achieved that the rock and soil between the grouting holes are fully reinforced. If the grouting pressure is reduced, not only will the diffusion radius of the grout be reduced, but the conventional grouting hole spacing cannot ensure that the surrounding rock and soil are fully reinforced, resulting in discontinuity of the grout and affecting the stress state of the grout-rock-soil mixture. Therefore, its improvement and innovation are imperative.
发明内容Summary of the invention
本发明的目的是提供一种防止隧道注浆加固引起地表***的防护结构及注浆方法，以解决上述现有技术存在的问题，能够有效防止注浆加固引起地表***。The object of the present invention is to provide a protective structure and a grouting method for preventing the grouting reinforcement of the tunnel from causing the ground surface uplift, so as to solve the above-mentioned problems in the prior art and effectively prevent the grouting reinforcement from causing the ground surface uplift.
为实现上述目的，本发明提供了如下方案：In order to achieve the above objective, the present invention provides the following solutions:
本发明提供一种防止隧道注浆加固引起地表***的防护结构，包括位于地层表面下方的隧道本体、反向曲拱和正向曲拱，所述反向曲拱设置于所述隧道本体正上方的地层内，所述反向曲拱由地表注浆形成，所述反向曲拱为呈向下凸起的拱形，所述隧道本体内轮廓的顶帮上设置有支护结构，围绕所述隧道本体内轮廓的顶帮，在所述支护结构的外侧设置有由钻孔注浆形成的所述正向曲拱，所述正向曲拱为呈向上凸起的拱形，所述正向曲拱、所述反向曲拱和所述支护结构共同形成防止超前注浆引起地表***的联合体支护结构。The present invention provides a protection structure for preventing ground uplift caused by grouting and reinforcement of tunnels, comprising a tunnel body located below the ground surface, a reverse curved arch and a forward curved arch, the reverse curved arch being arranged directly above the tunnel body In the stratum, the reverse arch is formed by surface grouting, the reverse arch is a downward convex arch, and the top edge of the inner contour of the tunnel is provided with a supporting structure surrounding the The top edge of the inner contour of the tunnel body is provided with the positive arch formed by drilling and grouting on the outer side of the supporting structure, and the positive arch is an upward convex arch. The forward curved arch, the reverse curved arch and the supporting structure jointly form a combined supporting structure that prevents advance grouting from causing ground uplift.
优选地，所述支护结构为设置在所述隧道本体内壁上的锚杆挂网喷锚支护或钢拱架支护或以上二者构成的联合支护。Preferably, the supporting structure is an anchor rod hanging on the inner wall of the tunnel body, or a steel arch support or a combined support composed of the above two.
优选地，所述反向曲拱的厚度为3-4m，所述正向曲拱的厚度大于2m。Preferably, the thickness of the reverse arch is 3-4 m, and the thickness of the forward arch is greater than 2 m.
优选地，所述反向曲拱沿宽度方向在水平地面的投影长度为L，作为反向曲拱的跨度；所述反向曲拱最低点到水平地面的深度为H，作为矢高；所述反向曲拱的矢跨比为△K，△K＝H/L，则△K为1/5-1/6。Preferably, the projection length of the reverse curved arch on the horizontal ground along the width direction is L, which is used as the span of the reverse curved arch; the depth from the lowest point of the reverse curved arch to the horizontal ground is H, which is used as the vector height; The rise-span ratio of reverse arch is △K, △K=H/L, then △K is 1/5-1/6.
优选地，所述隧道本体的竖向中心线、所述正向曲拱的竖向中心线以及所述反向曲拱的竖向中心线共线。Preferably, the vertical centerline of the tunnel body, the vertical centerline of the forward curved arch, and the vertical centerline of the reverse curved arch are collinear.
优选地，所述隧道本体内轮廓的顶帮上设置有朝向隧道走向倾斜设置的超前注浆管，所述超前注浆管的出口位于所述正向曲拱和所述反向曲拱覆盖范围之间。Preferably, an advanced grouting pipe arranged obliquely toward the direction of the tunnel is provided on the top of the inner contour of the tunnel body, and the outlet of the advanced grouting pipe is located in the coverage area of the forward curved arch and the reverse curved arch between.
一种基于上述的防止隧道注浆加固引起地表***的防护结构进行的隧道超前注浆方法，包括以下步骤：A tunnel advance grouting method based on the above-mentioned protective structure for preventing the tunnel grouting reinforcement from causing ground uplift, including the following steps:
A、地表钻孔注浆；隧道施工至待保护地段之前，沿隧道本体的走向，在其走向正上方具有松散岩土层的地层表面进行地表钻孔，地表钻孔呈梅花形布置，同一行地表钻孔的俯视中心连线与隧道走向垂直，同一行地表钻孔中，位于中心的钻孔深度最大，由中心向两侧钻孔深度依次递减，且同一行地表钻孔下端均位于该断面所在的设计反向曲拱范围内；往地表钻孔内安放可重复注浆管，通过可重复注浆管进行注浆操作，使浆液与松散岩土层形成一个整体支护结构，共同组成反向曲拱；A. Surface drilling and grouting; before the tunnel is constructed to the area to be protected, along the direction of the tunnel body, perform surface drilling on the surface of the stratum with loose rock and soil directly above its direction. The surface drilling is arranged in a plum blossom shape, in the same row The top-view center line of the surface boreholes is perpendicular to the tunnel direction. Among the surface boreholes in the same row, the borehole at the center has the largest depth, and the depth of the boreholes decreases from the center to both sides, and the lower ends of the surface boreholes in the same row are located on the section In the design of reverse arch range; place a repeatable grouting pipe into the surface borehole, and perform the grouting operation through the repeatable grouting pipe, so that the grout and the loose rock and soil form an integral supporting structure, which together form a reverse Arch towards
B、隧道支护；待隧道施工至待保护地段时，先掘出隧道本体的毛断面，进行初喷混凝土并安装支护结构，最后复喷混凝土；B. Tunnel support; when the tunnel is constructed to the area to be protected, first dig out the rough section of the tunnel body, first spray concrete and install the supporting structure, and finally re-spray concrete;
C、隧道钻孔注浆；复喷混凝土1天后，围绕隧道本体内轮廓的顶帮钻孔注浆形成的正向曲拱；C. Tunnel drilling and grouting; 1 day after re-spraying concrete, a positive arch formed by grouting around the top edge of the tunnel body contour;
D、超前注浆；在反向曲拱与正向曲拱之间进行超前注浆；D. Advance grouting; advance grouting between the reverse curved arch and the forward curved arch;
E、底板浇筑；对隧道的底板进行混凝土浇筑，形成符合设计要求的隧道断面尺寸。E. Bottom pouring; concrete pouring of the tunnel bottom plate to form a tunnel section size that meets the design requirements.
优选地，所述设计反向曲拱位于隧道走向的正上方的松散岩土层内，设计反向曲拱呈向下凸起的拱形，所述反向曲拱沿宽度方向在水平地面的投影长度为L，作为反向曲拱的跨度，反向曲拱最低点到水平地面的深度 为H，作为矢高，反向曲拱的矢跨比为△K，△K＝H/L，则△K为1/5-1/6。Preferably, the designed inverted arch is located in the loose rock and soil layer directly above the tunnel direction, the designed inverted arch is a downward convex arch, and the inverted arch is on the horizontal ground along the width direction. The projection length is L, as the span of the reverse arch, the depth from the lowest point of the reverse arch to the horizontal ground is H, as the vector height, the ratio of the span of the reverse arch is △K, △K=H/L, then △K is 1/5-1/6.
优选地，所述可重复注浆管的下端与设计反向曲拱下端面的间距相等。Preferably, the distance between the lower end of the repeatable grouting pipe and the lower end surface of the designed reverse arch is equal.
优选地，所述步骤A中注浆操作为：可重复注浆管下端离钻孔底不超过10cm，先进行初期注浆，通过可重复注浆管往注浆孔内注入固化浆液，初期注浆采用充填注浆，注浆压力控制在小于0.5Mpa，所使用注浆液为325#水泥、添加剂、水组成，其比例为1:0.08:2；待初期注浆结束2-3h，浆液达到初凝状态，浆液与松散岩土层中的松散岩层、砂土层初步粘结成一个整体，具有一定承载强度后，进行二次注浆，二次注浆的注浆压力大于初次注浆的注浆压力，且控制在小于3Mpa，采用后退分段式注浆，所使用注浆液为325#水泥、添加剂、水组成，其比例为1:0.08:2，采用后退分段式注浆厚度为3-4m，直至形成完整的反向曲拱，以达到提高松散岩土层强度的作用，通过初期注浆和二次注浆形成内部注浆加固体，内部注浆加固体与周围松散岩土层形成一个整体支护结构共同组成用于应力承载的反向曲拱。Preferably, the grouting operation in step A is: the lower end of the repeatable grouting pipe is no more than 10 cm from the bottom of the borehole, initial grouting is performed first, and solidified slurry is injected into the grouting hole through the repeatable grouting pipe. The grout adopts filling grouting, and the grouting pressure is controlled to be less than 0.5Mpa. The grouting liquid used is composed of 325# cement, additives, and water, and the ratio is 1:0.08:2; after the initial grouting is completed 2-3h, the grout reaches In the initial setting state, the grout is initially bonded to the loose rock and sand in the loose rock and soil to form a whole. After it has a certain bearing strength, the second grouting is carried out. The grouting pressure of the second grouting is greater than that of the initial grouting The grouting pressure is controlled to be less than 3Mpa, and the backward segmented grouting is used. The grouting fluid used is composed of 325# cement, additives and water, and the ratio is 1:0.08:2. The backward segmented grouting thickness is adopted. The length is 3-4m, until a complete reverse arch is formed to increase the strength of the loose rock and soil layer. The internal grouting and solidification are formed through the initial grouting and secondary grouting, and the internal grouting is solidified and the surrounding loose rock The soil layer forms an integral supporting structure together to form a reverse arch for stress bearing.
本发明相对于现有技术取得了以下有益技术效果：Compared with the prior art, the present invention has achieved the following beneficial technical effects:
本发明提供的防止隧道注浆加固引起地表***的防护结构及注浆方法，利用曲拱的空间稳定理论与常规的锚喷支护、钢拱架加喷锚支护或联合支护等被动支护形式有机结合，通过分层次、多次注浆和联合多种被动支护方式共同形成应力承载体，先后形成了反向曲拱和正向曲拱结构，改变隧(巷)道周围松散岩层、砂土层等松散岩土层的应力分布状态，将应力集中的峰值偏移出隧(巷)道的三带受力区，充分利用曲拱形状具有承载力大的特点，隔断了地层表面的动、静荷载对隧(巷)道的影响，同时也隔断了隧(巷)道超前注浆压力过大对地表道路、建构筑物的影响，分别保证了两者的相互稳定，可实现高压注浆，既控制了地层表面地面、建构筑物的变形，防治了地表的***，同时也充分实现了松散岩土层注浆加固的效果。通过高压注浆对松散的岩土体进行强度刚度的修复，提高了围岩的整体性和承载力，使隧(巷)道上部松散岩土体长久处于较好的稳定状态，从而可以实现对周围环境、岩土性质掌握不十分准确的情况下，通过反向曲拱的保护形成高压注浆。本发明的注浆方法应用范围广泛，对新掘和返修隧(巷) 道均适用，尤其适用于浅部隧(巷)道穿越松散岩层、砂土层的工程，本发明易形成一套完善的施工技术措施，具有方法简单，便于实施，机械化操作方便，支护效果好的特点，具有的工程推广应用价值，随着浅部地下工程的不断发展具有显著的经济效益。The protective structure and grouting method for preventing the surface uplift caused by the grouting reinforcement of the tunnel provided by the present invention utilizes the space stability theory of the curved arch and the conventional anchor and shotcrete support, steel arch frame plus shotcrete anchor support or combined support and other passive supports The protection forms are organically combined, and the stress-bearing body is formed by layering, multiple grouting and combined with multiple passive support methods, forming a reverse curved arch and a forward curved arch structure successively, changing the loose rock formations around the tunnel (lane), The stress distribution state of loose rock and soil layers such as sandy soil layer shifts the peak of stress concentration out of the three-zone stress area of the tunnel (roadway), and makes full use of the characteristic of large bearing capacity of the curved arch shape, which isolates the surface of the stratum. The impact of dynamic and static loads on the tunnel (lane), while also isolating the influence of the excessive pressure of the tunnel (lane) advanced grouting on the surface roads and structures, respectively, to ensure the mutual stability of the two, which can achieve high-pressure injection The grouting not only controls the deformation of the ground and the structures on the stratum surface, prevents the uplift of the ground surface, but also fully realizes the effect of grouting reinforcement on the loose rock and soil layer. The strength and stiffness of the loose rock and soil are repaired by high-pressure grouting, which improves the integrity and bearing capacity of the surrounding rock, and makes the loose rock and soil on the upper part of the tunnel (lane) stay in a good stable state for a long time, so that the When the surrounding environment and geotechnical properties are not very accurate, high-pressure grouting is formed through the protection of the reverse arch. The grouting method of the present invention has a wide range of applications and is suitable for both new excavation and repair of tunnels (lanes), especially for shallow tunnels (lanes) through loose rock and sand layers. The present invention is easy to form a complete set The construction technical measures of the project have the characteristics of simple method, easy implementation, convenient mechanized operation, and good supporting effect. They have the value of engineering promotion and application. With the continuous development of shallow underground projects, they have significant economic benefits.
附图说明Description of the drawings
为了更清楚地说明本发明实施例或现有技术中的技术方案，下面将对实施例中所需要使用的附图作简单地介绍，显而易见地，下面描述中的附图仅仅是本发明的一些实施例，对于本领域普通技术人员来讲，在不付出创造性劳动的前提下，还可以根据这些附图获得其他的附图。In order to explain the embodiments of the present invention or the technical solutions in the prior art more clearly, the following will briefly introduce the drawings needed in the embodiments. Obviously, the drawings in the following description are only some of the present invention. Embodiments, for those of ordinary skill in the art, without creative work, other drawings can be obtained from these drawings.
图1为本发明的整体布置剖面示意图；Figure 1 is a schematic cross-sectional view of the overall arrangement of the present invention;
图2为本发明中反向曲拱布置剖面示意图；Figure 2 is a schematic cross-sectional view of the arrangement of reverse curved arches in the present invention;
图3为本发明中超前注浆加固区布置剖面示意图；Figure 3 is a schematic diagram of the layout of the advanced grouting reinforcement zone in the present invention;
图4为本发明中反向连续曲拱防止注浆加固引起地表***方法的整体平面示意图；Figure 4 is an overall plan view of the method for preventing ground uplift caused by grouting reinforcement in reverse continuous arching in the present invention;
图中：1-地层表面；2-地表钻孔；3-可重复注浆管；4-松散岩土层；5-反向曲拱；6-超前注浆管；7-浅部注浆孔；8-隧道本体；9-隧道本体的竖向中心线；10-底板；11-正向曲拱；12-超前注浆加固区；13-锚杆挂网喷锚支护；14-隧道本体的横向中心线；15-隧道本体的毛断面；16-钢拱架支护。In the picture: 1- stratum surface; 2- surface drilling; 3- repeatable grouting pipe; 4- loose rock and soil layer; 5- reverse arch; 6-advance grouting pipe; 7- shallow grouting hole 8-tunnel body; 9-vertical centerline of tunnel body; 10-base plate; 11-positive curved arch; 12-advance grouting reinforcement area; 13-bolt hanging net and spray anchor support; 14-tunnel body The transverse centerline of the tunnel; 15- the gross section of the tunnel body; 16- the steel arch support.
具体实施方式Detailed ways
下面将结合本发明实施例中的附图，对本发明实施例中的技术方案进行清楚、完整地描述，显然，所描述的实施例仅仅是本发明一部分实施例，而不是全部的实施例。基于本发明中的实施例，本领域普通技术人员在没有做出创造性劳动前提下所获得的所有其他实施例，都属于本发明保护的范围。The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative work shall fall within the protection scope of the present invention.
本发明的目的是提供一种防止隧道注浆加固引起地表***的防护结构及注浆方法，以解决现有技术存在的问题。The purpose of the present invention is to provide a protective structure and a grouting method for preventing the grouting reinforcement of the tunnel from causing ground uplift, so as to solve the problems existing in the prior art.
为使本发明的上述目的、特征和优点能够更加明显易懂，下面结合附图和具体实施方式对本发明作进一步详细的说明。In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments.
本实施例提供一种防止隧道注浆加固引起地表***的防护结构，如图1-4所示，包括位于地层表面1下方的隧道本体8，隧道本体8正上方的地层内设置有由地表注浆形成的反向曲拱5，反向曲拱5为呈向下凸起的拱形，隧道本体8内轮廓的顶帮上设置有支护结构，围绕隧道本体内轮廓的顶帮，在支护结构的外侧设置有由钻孔注浆形成的正向曲拱11，正向曲拱11为呈向上凸起的拱形，正向曲拱11、反向曲拱5以及支护结构共同形成防止超前注浆引起地表***的联合体支护结构。This embodiment provides a protective structure for preventing the surface uplift caused by tunnel grouting reinforcement. As shown in Figs. 1-4, it includes a tunnel body 8 located below the stratum surface 1. The stratum directly above the tunnel body 8 is provided with ground The reverse curved arch 5 is formed by the slurry. The reverse curved arch 5 is a downwardly convex arch. The top edge of the inner contour of the tunnel body 8 is provided with a supporting structure, which surrounds the top edge of the inner contour of the tunnel body. The outer side of the protective structure is provided with a forward arch 11 formed by drilling and grouting. The forward arch 11 is an upward convex arch. The forward arch 11, the reverse arch 5 and the supporting structure are formed together Combination supporting structure to prevent the ground uplift caused by advanced grouting.
本实施例中，为保证使用效果，所述支护结构为设置在隧道本体8内壁上的锚杆挂网喷锚支护13或钢拱架支护16或以上二者构成的联合支护。In this embodiment, in order to ensure the use effect, the supporting structure is an anchor rod, net-sprayed anchor support 13 or a steel arch support 16 or a combined support formed on the inner wall of the tunnel body 8.
本实施例中，所述的反向曲拱5的厚度为3-4m，正向曲拱11的厚度大于2m。In this embodiment, the thickness of the reverse arch 5 is 3 to 4 m, and the thickness of the forward arch 11 is greater than 2 m.
本实施例中，所述反向曲拱5沿宽度方向在水平地面的投影长度为L，作为反向曲拱的跨度，反向曲拱5最低点到水平地面的深度为H，作为矢高，反向曲拱的矢跨比为△K，△K＝H/L，则△K为1/5-1/6。In this embodiment, the projection length of the reverse arch 5 on the horizontal ground along the width direction is L, as the span of the reverse arch, and the depth from the lowest point of the reverse arch 5 to the horizontal ground is H, as the vector height, The rise-span ratio of reverse arch is △K, △K=H/L, then △K is 1/5-1/6.
若地层表面不水平时，水平地面的基准取最低点。If the stratum surface is not level, take the lowest point as the datum of level ground.
所述正向曲拱11和反向曲拱5的间距大于2m，由于地下空间隧道的埋深不同，反向曲拱拱顶(最低点)距正向曲拱拱顶(最高点)的距离根据实际情况进行选择，在正、反两个曲拱的保护下，在其中间夹层进行高压注浆达到加固围岩体的作用，达到围岩体与注浆体协同受力的效果。The distance between the forward arch 11 and the reverse arch 5 is greater than 2m. Due to the different buried depths of underground space tunnels, the distance between the reverse arch vault (lowest point) and the forward arch vault (highest point) The choice is made according to the actual situation. Under the protection of the front and back arches, high pressure grouting is carried out in the middle interlayer to strengthen the surrounding rock mass and achieve the effect of synergistic force on the surrounding rock mass and the grouting body.
本实施例中，所述隧道本体8的竖向中心线9、正向曲拱11的竖向中心线以及反向曲拱5的竖向中心线共线。In this embodiment, the vertical centerline 9 of the tunnel body 8, the vertical centerline of the forward curved arch 11, and the vertical centerline of the reverse curved arch 5 are collinear.
本实施例中，所述的隧道本体8内轮廓的顶帮上设置有朝向隧道走向倾斜设置的超前注浆管6，超前注浆管6的出口位于正向曲拱11和反向曲拱5覆盖范围之间。In this embodiment, the inner contour of the tunnel body 8 is provided with an advanced grouting pipe 6 arranged obliquely toward the direction of the tunnel, and the outlet of the advanced grouting pipe 6 is located at the forward curved arch 11 and the reverse curved arch 5. Between coverage.
超前注浆管6按照现有规范进行布置即可，一般按照相对应隧道走向向外倾斜30°-60°布设，间距一般控制在0.5m左右，遇特殊地质情况可适当调整钻孔角度和间距，该技术为现有技术。具体为：在隧(巷)道内的顶帮打一定深度的注浆孔安装注浆管进行中深孔注浆作业，形成内部注浆加固体，在反向连续曲拱5和正向曲拱11的保护下，可适当提高中深 孔超前注浆的注浆压力，一般控制在8Mpa以下，所使用注浆液为425#水泥、添加剂、水组成，其比例为1:0.08:2。The advanced grouting pipe 6 can be arranged in accordance with the existing specifications. Generally, it is laid out according to the direction of the corresponding tunnel and inclined 30°-60°. The spacing is generally controlled at about 0.5m. The drilling angle and spacing can be adjusted appropriately in special geological conditions. , This technology is an existing technology. Specifically: drill a certain depth of grouting hole in the top of the tunnel (roadway) to install a grouting pipe for medium and deep hole grouting to form internal grouting and solidification, in the reverse continuous arch 5 and forward arch 11 Under the protection of, the grouting pressure of advanced grouting for medium and deep holes can be appropriately increased, generally controlled below 8Mpa. The grouting liquid used is composed of 425# cement, additives, and water, and the ratio is 1:0.08:2.
隧道本体8内轮廓的顶帮是由上部的圆弧形部分和连接在圆弧形部分两端下部竖直边部分组成的。The top edge of the inner contour of the tunnel body 8 is composed of an upper arc-shaped part and a lower vertical edge part connected to both ends of the arc-shaped part.
基于上述防止隧道注浆加固引起地表***的防护结构，本实施例还提供了上述防止地表***的隧道超前注浆方法，包括以下步骤：Based on the above-mentioned protective structure for preventing ground uplift caused by grouting reinforcement in tunnels, this embodiment also provides the above-mentioned advanced grouting method for tunnels to prevent ground uplift, including the following steps:
A、地表钻孔注浆A. Surface drilling and grouting
隧道施工至待保护地段之前，先对地层表面因施工需要迁移的临时设施进行转移，在合适位置布置注浆站，为后续的反向曲拱注浆做好准备，沿隧道本体的走向，在其走向正上方具有松散岩土层4的地层表面进行地表钻孔2，地表钻孔的直径以稍大于注浆管直径为宜，地表钻孔为梅花形布置，同一行钻孔的俯视中心连线与隧道走向垂直，同一行钻孔中，位于中心的钻孔深度最大，由中心向两侧钻孔深度依次递减，且同一行钻孔下端均位于该断面所在的设计反向曲拱范围内；Before the construction of the tunnel to the area to be protected, the temporary facilities that need to be relocated due to the construction of the stratum surface should be transferred, and the grouting station should be arranged at a suitable position to prepare for the subsequent reverse curved arch grouting. Surface drilling 2 is carried out on the surface of the stratum with loose rock and soil layer 4 directly above its strike. The diameter of the surface drilling should be slightly larger than the diameter of the grouting pipe. The surface drilling is arranged in a plum blossom shape. The line is perpendicular to the direction of the tunnel. In the same row of boreholes, the depth of the borehole at the center is the largest, and the depth of the boreholes decreases from the center to both sides, and the lower ends of the same row of boreholes are located within the design reverse arch range where the section is located ；
所述地表钻孔2的间距为0.4-0.6m；The spacing of the surface boreholes 2 is 0.4-0.6m;
往钻孔内安放可重复注浆管3，可重复注浆管选用硬质弹性好的塑料管(PVC管)，可重复注浆管底端密封，管壁上每隔一段距离(如15-20cm)钻有一圈出浆小孔，每圈等距设置一定数量的出浆小孔(如3-4个)，且各个可重复注浆管上出浆小孔的相对高度相同，以使浆液在注浆孔周围能均匀等效扩散。Place a repeatable grouting pipe 3 into the borehole. The repeatable grouting pipe is made of a hard and flexible plastic pipe (PVC pipe). The bottom end of the repeatable grouting pipe is sealed, and the pipe wall is at intervals (such as 15- 20cm) Drill a circle of grout holes, each circle is equidistant with a certain number of grout holes (such as 3-4), and the relative height of the grout holes on each repeatable grouting pipe is the same to make the grout It can spread evenly and equivalently around the grouting hole.
通过可重复注浆管3进行注浆操作，使浆液与松散岩土层4形成一个整体支护结构，共同组成反向曲拱5；The grouting operation is carried out through the repeatable grouting pipe 3, so that the grout and the loose rock and soil layer 4 form an integral supporting structure, which together form a reverse arch 5;
B、隧道支护B. Tunnel support
待隧道施工至待保护地段时，先掘出隧道本体的毛断面15，进行初喷混凝土并安装支护结构，最后复喷混凝土；When the tunnel is constructed to the area to be protected, first dig out the gross section 15 of the tunnel body, carry out the initial spraying of concrete and install the supporting structure, and finally re-spray the concrete;
具体方法为：待隧道施工至待保护地段时，先掘出隧道本体的毛断面15，立即进行初喷混凝土，初喷混凝土厚度一般为20-30mm，然后根据周围岩土层的特性和强度等级对开挖的隧(巷)道进行锚杆挂网喷锚支护13、钢拱架支护16或二者联合支护形成支护结构，最后复喷混凝土，厚度一般为80-100mm，复喷完成后要对欠挖的部位进行人工处理，对超挖 的部位进行填平，并将外漏的锚杆、锚索端头进行适当处理，最后对整个隧(巷)道进行找平处理，以保证整个隧(巷)道断面的形状大小符合设计。The specific method is: when the tunnel is constructed to the area to be protected, first dig out the rough section 15 of the tunnel body, and immediately carry out the initial spraying of concrete. The thickness of the initial spraying concrete is generally 20-30mm, and then according to the characteristics and strength grade of the surrounding rock and soil. The excavated tunnel (lane) shall be supported by anchor rod hanging net and shotcrete anchor 13, steel arch support 16 or the combination of the two to form a supporting structure. Finally, spray concrete with a thickness of 80-100mm. After spraying is completed, the under-excavated parts should be manually treated, the over-excavated parts should be filled in, and the leaked anchor rods and anchor cable ends should be properly treated, and finally the entire tunnel (lane) should be leveled. To ensure that the shape and size of the entire tunnel (lane) section conform to the design.
C、隧道钻孔注浆C. Tunnel drilling and grouting
复喷混凝土1天后，围绕隧道本体内轮廓的顶帮钻孔注浆形成的正向曲拱11；One day after spraying the concrete, the positive curved arch 11 formed by grouting around the top edge of the tunnel body contour;
具体方法为：复喷混凝土结束1天后，在隧(巷)道顶帮打深度2m以下的浅部注浆孔7，然后安装注浆管进行注浆，注浆压力一般控制在5Mpa以下，所使用注浆液为425#水泥、添加剂、水组成，其比例为1:0.08:2，围绕隧(巷)道顶帮形状形成正向曲拱11，使其与支护结构共同形成联合体支护结构。The specific method is: 1 day after the compound shotcrete is finished, drill a shallow grouting hole 7 with a depth of less than 2m on the top of the tunnel (lane), and then install a grouting pipe for grouting. The grouting pressure is generally controlled below 5Mpa. The grouting solution used is composed of 425# cement, additives, and water, and the ratio is 1:0.08:2. It forms a forward curved arch 11 around the top of the tunnel (lane), so that it and the supporting structure form a combined support护结构。 Protection structure.
D、超前注浆D. Advance grouting
在反向曲拱5与正向曲拱11之间的超前注浆加固区12进行超前注浆加固；Carry out advanced grouting reinforcement in the advanced grouting reinforcement zone 12 between the reverse curved arch 5 and the forward curved arch 11;
具体方法为：在隧(巷)道内的顶帮打一定深度的注浆孔并安装超前注浆管6进行中深孔注浆作业，形成内部注浆加固体，超前注浆管6的出口位于正向曲拱11和反向曲拱5覆盖范围之间，在反向曲拱5和正向曲拱11的保护下，可适当提高中深孔超前注浆6的注浆压力，一般控制在8Mpa以下，所使用注浆液为425#水泥、添加剂、水组成，其比例为1:0.08:2，超前注浆管间距一般控制在0.5m左右，遇特殊地质情况可适当调整注浆孔钻孔角度和间距。The specific method is: drill a certain depth of grouting hole in the top of the tunnel (roadway) and install the advanced grouting pipe 6 for medium and deep hole grouting operations to form internal grouting and solidification. The outlet of the advanced grouting pipe 6 is located at Between the coverage of the forward arch 11 and the reverse arch 5, under the protection of the reverse arch 5 and the forward arch 11, the grouting pressure of the medium and deep hole advanced grouting 6 can be appropriately increased, generally controlled at 8Mpa Below, the grouting fluid used is composed of 425# cement, additives, and water, and the ratio is 1:0.08:2. The distance between the advanced grouting pipes is generally controlled at about 0.5m, and the grouting hole drilling can be adjusted appropriately in case of special geological conditions. Angle and spacing.
E、底板浇筑E. Floor pouring
对隧道的底板10进行混凝土浇筑，形成符合设计要求的隧道断面尺寸。Concrete is poured on the bottom plate 10 of the tunnel to form a tunnel section size that meets the design requirements.
所述的设计反向曲拱位于隧道走向的正上方的松散岩土层4内，设计反向曲拱呈向下凸起的拱形，所述反向曲拱5沿宽度方向在水平地面的投影长度为L，作为反向曲拱的跨度，反向曲拱5最低点到水平地面的深度为H，作为矢高，反向曲拱的矢跨比为△K，△K＝H/L，则△K为1/5-1/6；The designed inverted arch is located in the loose rock and soil layer 4 directly above the tunnel direction, and the designed inverted arch is a downwardly convex arch, and the inverted arch 5 is on the horizontal ground along the width direction. The projection length is L, as the span of the reverse arch, the depth from the lowest point of the reverse arch 5 to the horizontal ground is H, as the vector height, the ratio of the span of the reverse arch is △K, △K=H/L, Then △K is 1/5-1/6;
所述可重复注浆管3的下端与设计反向曲拱下端面的间距相等。The distance between the lower end of the repeatable grouting pipe 3 and the lower end surface of the designed reverse arch is equal.
地表钻孔深度的确定方法有以下两种：There are two methods for determining the depth of surface drilling:
a、地面反向连续曲拱注浆属于地表层注浆，钻孔深度一般在6-7m， 具体深度视松散岩层、砂土层构成的松散岩土层的厚度或隧(巷)道距地表的距离而定，再根据选取的ΔK，可计算出L；a. Ground reverse continuous curved arch grouting belongs to surface grouting. The drilling depth is generally 6-7m. The specific depth depends on the thickness of the loose rock and soil layer or the tunnel (lane) distance from the ground surface. Depends on the distance, and then according to the selected ΔK, L can be calculated;
b、实际中待保护建构筑物的宽度是容易测量的，则L就易确定，选择合适的ΔK后，则注浆孔深度H就能计算得到，但必须满足正向曲拱11和反向曲拱5的间距大于2m的要求。b. In practice, the width of the structure to be protected is easy to measure, so L is easy to determine. After choosing the appropriate ΔK, the grouting hole depth H can be calculated, but it must meet the requirements of forward curvature 11 and reverse curvature. The distance between arches 5 is greater than the requirement of 2m.
所述步骤A中注浆操作为：The grouting operation in step A is:
可重复注浆管下端离钻孔底不超过10cm，先进行初期注浆，通过可重复注浆管往注浆孔内注入固化浆液，初期注浆采用充填注浆，注浆压力控制在小于0.5Mpa(防止注浆压力过大破坏反向曲拱5的形状，影响整体松散岩土层的承载力)，所使用注浆液为325#水泥、添加剂、水组成，其比例为1:0.08:2。The lower end of the repeatable grouting pipe is no more than 10cm away from the bottom of the borehole. The initial grouting is performed first. The solidified slurry is injected into the grouting hole through the repeatable grouting pipe. The initial grouting adopts filling grouting, and the grouting pressure is controlled to be less than 0.5 Mpa (to prevent excessive grouting pressure from damaging the shape of the reverse arch 5 and affecting the bearing capacity of the overall loose rock and soil layer). The grouting fluid used is composed of 325# cement, additives, and water, and the ratio is 1:0.08: 2.
待初期注浆结束2-3h，浆液达到初凝状态，浆液与松散岩土层(4)中的松散岩层、砂土层初步粘结成一个整体，具有一定承载强度后，进行二次注浆，二次注浆的注浆压力大于初次注浆的注浆压力，且控制在小于3Mpa，采用后退分段式注浆，所使用注浆液为325#水泥、添加剂、水组成，其比例为1:0.08:2，采用后退分段式注浆厚度为3-4m，直至形成完整的反向曲拱5，以达到提高松散岩土层强度的作用，注浆完毕后，应用水冲洗注浆管，清除管内残留浆液，通过初期注浆和二次注浆形成内部注浆加固体，内部注浆加固体与周围松散岩土层形成一个整体支护结构共同组成用于应力承载的反向曲拱5。After the initial grouting is completed for 2-3 hours, the grout reaches the initial setting state, and the grout is initially bonded to the loose rock and sand in the loose rock and soil layer (4) to form a whole. After having a certain bearing strength, perform secondary grouting , The grouting pressure of the secondary grouting is greater than the grouting pressure of the first grouting and is controlled to be less than 3Mpa. The backward segmented grouting is adopted. The grouting liquid used is composed of 325# cement, additives and water, and the ratio is 1:0.08:2, adopt backward segmented grouting with a thickness of 3-4m, until a complete reverse arch 5 is formed, so as to improve the strength of the loose rock and soil layer. After the grouting is completed, the grouting should be washed with water Pipe, remove the remaining grout in the pipe, through the initial grouting and secondary grouting to form internal grouting and solids, the internal grouting and solids and the surrounding loose rock and soil layers form an integral supporting structure together to form a reverse curve for stress bearing Arch 5.
所述后退分段式注浆为现有技术，简单来说就是首次注浆完成后提起注浆管一定距离，比如20-30cm，进行二次注浆，二次注浆完成后再次将注浆管提起20-30cm进行三次注浆，如此反复，直到注浆厚度达到3-4m。The backward segmented grouting is the prior art. Simply put, the grouting pipe is lifted for a certain distance after the first grouting is completed, such as 20-30cm, and then the second grouting is performed, and after the second grouting is completed, the grouting is performed again The pipe is raised 20-30cm for three grouting, and so on, until the grouting thickness reaches 3-4m.
由上述情况可以清楚的看出，本发明利用曲拱的空间稳定理论与常规的锚喷支护、钢拱架加喷锚支护或联合支护等被动支护形式有机结合，通过分层次、多次注浆和联合多种被动支护方式共同形成应力承载体，先后形成了反向曲拱和正向曲拱结构，改变隧(巷)道周围松散岩层、砂土层等松散岩土层的应力分布状态，将应力集中的峰值偏移出隧(巷)道的三带受力区，充分利用曲拱形状具有承载力大的特点，隔断了地层表面的动、静荷载对隧(巷)道的影响，同时也隔断了隧(巷)道超前注浆压力过大对地表 道路、建构筑物的影响，分别保证了两者的相互稳定，可实现高压注浆，既控制了地层表面地面、建构筑物的变形，防治了地表的***，同时也充分实现了松散岩土层注浆加固的效果。通过高压注浆对松散的岩土体进行强度刚度的修复，提高了围岩的整体性和承载力，使隧(巷)道上部松散岩土体长久处于较好的稳定状态，从而可以实现对周围环境、岩土性质掌握不十分准确的情况下，通过反向曲拱的保护形成高压注浆。本发明的方法应用范围广泛，对新掘和返修隧(巷)道均适用，尤其适用于浅部隧(巷)道穿越松散岩层、砂土层的工程，本发明易形成一套完善的施工技术措施，具有方法简单，便于实施，机械化操作方便，支护效果好的特点，具有的工程推广应用价值，随着浅部地下工程的不断发展具有显著的经济效益。It can be clearly seen from the above situation that the present invention uses the spatial stability theory of curved arches to organically combine passive support forms such as conventional bolting and shotcrete support, steel arches plus shotcrete anchor support, or combined support. Multiple grouting and a combination of multiple passive support methods jointly form a stress bearing body, which has successively formed a reverse curved arch and a forward curved arch structure, which changes the loose rock and sand layers around the tunnel (lane). The stress distribution state shifts the peak of stress concentration out of the three-zone stress area of the tunnel (lane), making full use of the arch shape, which has the characteristics of large bearing capacity, and partitions the dynamic and static loads on the ground surface to the tunnel (lane) At the same time, it also isolates the influence of excessive grouting pressure in the tunnel (lane) on the surface roads and structures, respectively ensuring the mutual stability of the two, which can achieve high-pressure grouting, which not only controls the surface, ground, and The deformation of the structure prevents the uplift of the ground surface, and at the same time fully realizes the effect of grouting reinforcement of the loose rock and soil layer. The strength and stiffness of the loose rock and soil are repaired by high-pressure grouting, which improves the integrity and bearing capacity of the surrounding rock, and makes the loose rock and soil on the upper part of the tunnel (lane) stay in a good stable state for a long time, so that the When the surrounding environment and geotechnical properties are not very accurate, high-pressure grouting is formed through the protection of the reverse arch. The method of the present invention has a wide range of applications, and is suitable for both new excavation and repair of tunnels (lanes), and is especially suitable for projects where shallow tunnels (lanes) pass through loose rock and sand layers. The present invention is easy to form a complete set of construction Technical measures have the characteristics of simple method, easy implementation, convenient mechanized operation and good supporting effect, and have the value of engineering promotion and application. With the continuous development of shallow underground projects, they have significant economic benefits.
本发明应用了具体个例对本发明的原理及实施方式进行了阐述，以上实施例的说明只是用于帮助理解本发明的方法及其核心思想；同时，对于本领域的一般技术人员，依据本发明的思想，在具体实施方式及应用范围上均会有改变之处。综上，本说明书内容不应理解为对本发明的限制。The present invention uses specific examples to illustrate the principles and implementation of the present invention. The description of the above examples is only used to help understand the method and core idea of the present invention; at the same time, for those of ordinary skill in the art, according to the present invention There will be changes in the specific implementation and scope of application. In summary, the content of this specification should not be construed as a limitation of the present invention.

Claims (10)

  1. 一种防止隧道注浆加固引起地表***的防护结构，其特征在于：包括位于地层表面(1)下方的隧道本体(8)、反向曲拱(5)和正向曲拱(11)，所述反向曲拱(5)设置于所述隧道本体(8)正上方的地层内，所述反向曲拱(5)由地表注浆形成，所述反向曲拱(5)为呈向下凸起的拱形，所述隧道本体(8)内轮廓的顶帮上设置有支护结构，围绕所述隧道本体(8)内轮廓的顶帮，在所述支护结构的外侧设置有由钻孔注浆形成的所述正向曲拱(11)，所述正向曲拱(11)为呈向上凸起的拱形，所述正向曲拱(11)、所述反向曲拱(5)和所述支护结构共同形成防止超前注浆引起地表***的联合体支护结构。A protective structure for preventing tunnel grouting reinforcement from causing ground uplift, which is characterized by comprising a tunnel body (8) located below the ground surface (1), a reverse arch (5) and a forward arch (11). The reverse curved arch (5) is arranged in the stratum directly above the tunnel body (8). The reverse curved arch (5) is formed by surface grouting, and the reverse curved arch (5) is downward A convex arch shape, a supporting structure is provided on the top edge of the inner contour of the tunnel body (8), and the top edge surrounding the inner contour of the tunnel body (8) is provided with a support structure on the outside of the supporting structure The forward arch (11) formed by drilling and grouting, the forward arch (11) is an upward convex arch, the forward arch (11), the reverse arch (5) Together with the supporting structure, a combined supporting structure is formed to prevent the ground uplift caused by advanced grouting.
  2. 根据权利要求1所述的防止隧道注浆加固引起地表***的防护结构，其特征在于：所述支护结构为设置在所述隧道本体(8)内壁上的锚杆挂网喷锚支护(13)或钢拱架支护(16)或以上二者构成的联合支护。The protective structure for preventing ground uplift caused by tunnel grouting reinforcement according to claim 1, characterized in that: the supporting structure is an anchor rod, net, and spray anchor provided on the inner wall of the tunnel body (8). 13) Or steel arch support (16) or a combined support composed of the above two.
  3. 根据权利要求1所述的防止隧道注浆加固引起地表***的防护结构，其特征在于：所述反向曲拱(5)的厚度为3-4m，所述正向曲拱(11)的厚度大于2m。The protective structure for preventing ground uplift caused by tunnel grouting reinforcement according to claim 1, characterized in that: the thickness of the reverse arch (5) is 3-4m, and the thickness of the forward arch (11) More than 2m.
  4. 根据权利要求1所述的防止隧道注浆加固引起地表***的防护结构，其特征在于：所述反向曲拱(5)沿宽度方向在水平地面的投影长度为L，作为反向曲拱的跨度；所述反向曲拱(5)最低点到水平地面的深度为H，作为矢高；所述反向曲拱(5)的矢跨比为△K，△K＝H/L，则△K为1/5-1/6。The protective structure for preventing ground uplift caused by tunnel grouting reinforcement according to claim 1, characterized in that: the projection length of the reverse curved arch (5) on the horizontal ground along the width direction is L, as the reverse curved arch Span; the depth from the lowest point of the reverse arch (5) to the horizontal ground is H, as the vector height; the rise-span ratio of the reverse arch (5) is △K, △K=H/L, then △ K is 1/5-1/6.
  5. 根据权利要求1所述的防止隧道注浆加固引起地表***的防护结构，其特征在于：所述隧道本体(8)的竖向中心线(9)、所述正向曲拱(11)的竖向中心线以及所述反向曲拱(5)的竖向中心线共线。The protective structure for preventing ground uplift caused by tunnel grouting reinforcement according to claim 1, characterized in that: the vertical centerline (9) of the tunnel body (8) and the vertical curve of the forward arch (11) Collinear to the centerline and the vertical centerline of the reverse arch (5).
  6. 根据权利要求1所述的防止隧道注浆加固引起地表***的防护结构，其特征在于：所述隧道本体(8)内轮廓的顶帮上设置有朝向隧道走向倾斜设置的超前注浆管(6)，所述超前注浆管(6)的出口位于所述正向曲拱(11)和所述反向曲拱(5)覆盖范围之间。The protective structure for preventing ground uplift caused by tunnel grouting reinforcement according to claim 1, characterized in that: an advanced grouting pipe (6) arranged obliquely toward the direction of the tunnel is provided on the top of the inner contour of the tunnel body (8) ), the outlet of the advanced grouting pipe (6) is located between the coverage of the forward curved arch (11) and the reverse curved arch (5).
  7. 一种基于权利要求1所述的防止隧道注浆加固引起地表***的防 护结构的隧道超前注浆方法，其特征在于，包括以下步骤：A tunnel advance grouting method based on the protective structure for preventing ground uplift caused by tunnel grouting reinforcement according to claim 1, characterized in that it comprises the following steps:
    A、地表钻孔注浆；隧道施工至待保护地段之前，沿隧道本体的走向，在其走向正上方具有松散岩土层(4)的地层表面进行地表钻孔，地表钻孔(2)呈梅花形布置，同一行地表钻孔(2)的俯视中心连线与隧道走向垂直，同一行地表钻孔(2)中，位于中心的钻孔深度最大，由中心向两侧钻孔深度依次递减，且同一行地表钻孔(2)下端均位于该断面所在的设计反向曲拱范围内；往地表钻孔(2)内安放可重复注浆管(3)，通过可重复注浆管(3)进行注浆操作，使浆液与松散岩土层(4)形成一个整体支护结构，共同组成反向曲拱(5)；A. Surface drilling and grouting; before the tunnel is constructed to the area to be protected, along the direction of the tunnel body, perform surface drilling on the surface of the ground with the loose rock and soil layer (4) directly above its direction, and the surface drilling (2) is Plum blossom arrangement, the top-view center line of the surface boreholes (2) in the same row is perpendicular to the tunnel direction. Among the surface boreholes (2) in the same row, the depth of the borehole at the center is the largest, and the depth of the borehole decreases from the center to both sides. , And the lower ends of the surface boreholes (2) in the same row are all located within the design reverse arch range where the section is located; a repeatable grouting pipe (3) is placed in the surface borehole (2), and the repeatable grouting pipe ( 3) Carry out grouting operation to make the grout and the loose rock and soil layer (4) form an integral supporting structure, which together form a reverse arch (5);
    B、隧道支护；待隧道施工至待保护地段时，先掘出隧道本体的毛断面(15)，进行初喷混凝土并安装支护结构，最后复喷混凝土；B. Tunnel support; when the tunnel is constructed to the area to be protected, first dig out the rough section (15) of the tunnel body, carry out the initial spraying of concrete and install the supporting structure, and finally re-spray the concrete;
    C、隧道钻孔注浆；复喷混凝土1天后，围绕隧道本体内轮廓的顶帮钻孔注浆形成的正向曲拱(11)；C. Tunnel drilling and grouting; 1 day after re-spraying concrete, a positive curved arch (11) formed by drilling and grouting around the top of the tunnel body contour
    D、超前注浆；在反向曲拱(5)与正向曲拱(11)之间进行超前注浆；D. Advance grouting; advance grouting between the reverse curved arch (5) and the forward curved arch (11);
    E、底板浇筑；对隧道的底板(10)进行混凝土浇筑，形成符合设计要求的隧道断面尺寸。E. Bottom plate pouring; concrete pouring of the tunnel bottom plate (10) to form a tunnel section size that meets the design requirements.
  8. 根据权利要求7所述的隧道超前注浆方法，其特征在于：所述设计反向曲拱位于隧道走向的正上方的松散岩土层(4)内，设计反向曲拱呈向下凸起的拱形，所述反向曲拱(5)沿宽度方向在水平地面的投影长度为L，作为反向曲拱的跨度，反向曲拱(5)最低点到水平地面的深度为H，作为矢高，反向曲拱的矢跨比为△K，△K＝H/L，则△K为1/5-1/6。The tunnel advance grouting method according to claim 7, characterized in that: the designed reverse arch is located in the loose rock and soil layer (4) directly above the tunnel direction, and the designed reverse arch is convex downward The length of the projection of the reverse arch (5) on the horizontal ground along the width direction is L, as the span of the reverse arch, and the depth from the lowest point of the reverse arch (5) to the horizontal ground is H, As the height of the arrow, the rise-span ratio of the reverse arch is △K, △K=H/L, then △K is 1/5-1/6.
  9. 根据权利要求8所述的隧道超前注浆方法，其特征在于：所述可重复注浆管(3)的下端与设计反向曲拱下端面的间距相等。The tunnel advanced grouting method according to claim 8, characterized in that the distance between the lower end of the repeatable grouting pipe (3) and the lower end surface of the designed reverse arch is equal.
  10. 根据权利要求7所述的隧道超前注浆方法，其特征在于：所述步骤A中注浆操作为：可重复注浆管(3)下端离钻孔底不超过10cm，先进行初期注浆，通过可重复注浆管(3)往注浆孔内注入固化浆液，初期注浆采用充填注浆，注浆压力控制在小于0.5Mpa，所使用注浆液为325#水泥、添加剂、水组成，其比例为1:0.08:2；待初期注浆结束2-3h，浆液 达到初凝状态，浆液与松散岩土层(4)中的松散岩层、砂土层初步粘结成一个整体，具有一定承载强度后，进行二次注浆，二次注浆的注浆压力大于初次注浆的注浆压力，且控制在小于3Mpa，采用后退分段式注浆，所使用注浆液为325#水泥、添加剂、水组成，其比例为1:0.08:2，采用后退分段式注浆厚度为3-4m，直至形成完整的反向曲拱(5)，以达到提高松散岩土层强度的作用，通过初期注浆和二次注浆形成内部注浆加固体，内部注浆加固体与周围松散岩土层形成一个整体支护结构共同组成用于应力承载的反向曲拱(5)。The tunnel advance grouting method according to claim 7, characterized in that the grouting operation in step A is: the lower end of the repeatable grouting pipe (3) is not more than 10 cm from the bottom of the borehole, and the initial grouting is performed first, Inject solidified grout into the grouting hole through the repeatable grouting pipe (3). The initial grouting adopts filling grouting, and the grouting pressure is controlled to be less than 0.5Mpa. The grouting liquid used is composed of 325# cement, additives and water. The ratio is 1:0.08:2; after the initial grouting ends 2-3h, the grout reaches the initial setting state, and the grout and the loose rock and sand in the loose rock and soil layer (4) are initially bonded into a whole, with a certain After the bearing strength, the second grouting is carried out. The grouting pressure of the second grouting is greater than the grouting pressure of the first grouting and is controlled to be less than 3Mpa. The backward segmented grouting is adopted. The grouting liquid used is 325# cement , Additives, water composition, the ratio is 1:0.08:2, the backward segmented grouting thickness is 3-4m, until a complete reverse arch (5) is formed, so as to improve the strength of the loose rock and soil layer , Through the initial grouting and secondary grouting to form internal grouting and solidification, the internal grouting and solidification and the surrounding loose rock and soil layer form an integral supporting structure together to form a reverse arch for stress bearing (5).
PCT/CN2020/070390 2019-06-13 2020-01-06 Protection structure for preventing ground heave caused by tunnel grouting reinforcement and grouting method WO2020248596A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
CN201910511046.2 2019-06-13
CN201910511046.2A CN110118090B (en) 2019-06-13 2019-06-13 Protective structure for preventing earth surface bulge caused by tunnel grouting reinforcement

Publications (1)

Publication Number Publication Date
WO2020248596A1 true WO2020248596A1 (en) 2020-12-17

Family

ID=67523948

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/CN2020/070390 WO2020248596A1 (en) 2019-06-13 2020-01-06 Protection structure for preventing ground heave caused by tunnel grouting reinforcement and grouting method

Country Status (2)

Country Link
CN (1) CN110118090B (en)
WO (1) WO2020248596A1 (en)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113153379A (en) * 2021-04-27 2021-07-23 重庆永昂实业有限公司 Tunnel water-proof and drainage system and construction process
CN114263163A (en) * 2021-12-29 2022-04-01 成都大学 Grouting reinforcement method for diversion culvert passing through gravel stratum in high and cold regions and construction method
CN114483091A (en) * 2021-12-02 2022-05-13 中南大学 Sectional grouting method for large tunnel pipe shed
CN114856578A (en) * 2022-04-20 2022-08-05 中铁一局集团有限公司 Freezing and in-hole grouting improved combined bearing stratum reinforcing scheme

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN110118090B (en) * 2019-06-13 2024-03-22 河南理工大学 Protective structure for preventing earth surface bulge caused by tunnel grouting reinforcement
CN110985055B (en) * 2019-12-20 2021-04-09 中铁南方投资集团有限公司 Tunnel grouting and drainage synchronous construction method for controlling surface uplift
CN112942307B (en) * 2021-01-27 2022-10-25 山东大学 Loose soil layer grouting reinforcement method and coastal karst area grouting reinforcement method
CN113551655B (en) * 2021-07-20 2023-04-07 杭州伟业建设集团有限公司 Tunnel surpasses owes detection device and detecting system who digs
CN115045299B (en) * 2022-07-26 2024-02-02 杭州市西站枢纽开发有限公司 Deep foundation pit side wall reinforcing structure with electroosmosis drainage function and construction method

Citations (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR100760293B1 (en) * 2007-03-23 2007-09-19 주식회사 영신토건 Tunnel construction method for shallow overburden tunnel
CN101824824A (en) * 2010-04-30 2010-09-08 南京市市政设计研究院有限责任公司 Construction method of controlling raised deformation of existing buildings under foundation pits through pile slab supporting and protection
CN104533434A (en) * 2014-12-28 2015-04-22 上海隧道工程股份有限公司 Construction method of rectangular ultra-shallow covered soil tunnel
CN107044290A (en) * 2017-06-22 2017-08-15 张玉芳 The vertical slip casting steel floral tube in tunnel top props up the integral reinforcing method being combined at the beginning of tunnel
CN109162722A (en) * 2018-10-11 2019-01-08 中国石油大学(华东) It is applicable in the advanced compacting grouting and reinforcing method in loose weak stratum of shallow-depth-excavation tunnel
CN109296385A (en) * 2018-10-23 2019-02-01 杭州市市政工程集团有限公司 A kind of reinforcement means of the large span mountain tunnel hole top soil body
CN109372556A (en) * 2018-09-30 2019-02-22 淮阴工学院 A kind of sandwich arch and construction method suitable for high stressed soft rock tunnel supporting roadway surrounding rock
CN208605184U (en) * 2018-06-29 2019-03-15 中铁十五局集团有限公司 The ruggedized construction of loose highfill embankment is worn under a kind of large cross-section tunnel
CN110118090A (en) * 2019-06-13 2019-08-13 河南理工大学 For preventing tunnel grouting reinforcing from causing the safeguard structure of surface uplift
CN210068175U (en) * 2019-06-13 2020-02-14 河南理工大学 A protective structure for preventing tunnel slip casting reinforcement from arousing earth's surface uplift

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
AUPS310702A0 (en) * 2002-06-21 2002-07-11 Industrial Rollformers Pty Limited Rock bolting system
CN105484751A (en) * 2015-02-04 2016-04-13 中铁隧道勘测设计院有限公司 Method for preventing large-section rectangular pipe-jacking tunnel from generating soil loading phenomenon
CN108194100A (en) * 2017-12-21 2018-06-22 山东科技大学 A kind of accurate three-dimensional prestress strengthening method of crack coal and rock
CN108842523A (en) * 2018-05-11 2018-11-20 中铁二院工程集团有限责任公司 In-strong expansive rock or expansive soils ballastless track of high-speed railway foundation stabilization construction and construction method

Patent Citations (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR100760293B1 (en) * 2007-03-23 2007-09-19 주식회사 영신토건 Tunnel construction method for shallow overburden tunnel
CN101824824A (en) * 2010-04-30 2010-09-08 南京市市政设计研究院有限责任公司 Construction method of controlling raised deformation of existing buildings under foundation pits through pile slab supporting and protection
CN104533434A (en) * 2014-12-28 2015-04-22 上海隧道工程股份有限公司 Construction method of rectangular ultra-shallow covered soil tunnel
CN107044290A (en) * 2017-06-22 2017-08-15 张玉芳 The vertical slip casting steel floral tube in tunnel top props up the integral reinforcing method being combined at the beginning of tunnel
CN208605184U (en) * 2018-06-29 2019-03-15 中铁十五局集团有限公司 The ruggedized construction of loose highfill embankment is worn under a kind of large cross-section tunnel
CN109372556A (en) * 2018-09-30 2019-02-22 淮阴工学院 A kind of sandwich arch and construction method suitable for high stressed soft rock tunnel supporting roadway surrounding rock
CN109162722A (en) * 2018-10-11 2019-01-08 中国石油大学(华东) It is applicable in the advanced compacting grouting and reinforcing method in loose weak stratum of shallow-depth-excavation tunnel
CN109296385A (en) * 2018-10-23 2019-02-01 杭州市市政工程集团有限公司 A kind of reinforcement means of the large span mountain tunnel hole top soil body
CN110118090A (en) * 2019-06-13 2019-08-13 河南理工大学 For preventing tunnel grouting reinforcing from causing the safeguard structure of surface uplift
CN210068175U (en) * 2019-06-13 2020-02-14 河南理工大学 A protective structure for preventing tunnel slip casting reinforcement from arousing earth's surface uplift

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113153379A (en) * 2021-04-27 2021-07-23 重庆永昂实业有限公司 Tunnel water-proof and drainage system and construction process
CN113153379B (en) * 2021-04-27 2024-01-09 重庆永昂实业有限公司 Tunnel waterproof and drainage system and construction process
CN114483091A (en) * 2021-12-02 2022-05-13 中南大学 Sectional grouting method for large tunnel pipe shed
CN114263163A (en) * 2021-12-29 2022-04-01 成都大学 Grouting reinforcement method for diversion culvert passing through gravel stratum in high and cold regions and construction method
CN114856578A (en) * 2022-04-20 2022-08-05 中铁一局集团有限公司 Freezing and in-hole grouting improved combined bearing stratum reinforcing scheme

Also Published As

Publication number Publication date
CN110118090A (en) 2019-08-13
CN110118090B (en) 2024-03-22

Similar Documents

Publication Publication Date Title
WO2020248596A1 (en) Protection structure for preventing ground heave caused by tunnel grouting reinforcement and grouting method
CN104612162B (en) A kind of Deep Foundation Pit of Metro Stations excavation construction method
CN102296961B (en) Karst tunnel large-scale cavern processing method
CN105240024B (en) A kind of method of parallel shield method enlarging construction subway station
CN110617067B (en) Low-risk construction method for full-section boundary advanced pipe shed of extremely-soft surrounding rock tunnel
CN105201516B (en) A kind of main structure of subway station and its tetrad arch PBA excavating construction methods
CN106437726A (en) Ground fracture crushed zone passing construction method for shallow-buried tunnel excavation
CN114233385B (en) Treatment method for mud-bursting water of inclined shaft
CN111119128B (en) Danger-removing, reinforcing and seepage-proofing method for natural rock-fill dam of barrier lake
CN112663625A (en) Construction and protection method for shallow-buried bias-pressure weak surrounding rock tunnel portal in alpine region
CN107503362A (en) A kind of compound antiskid piling wall retaining structure and construction method suitable for reservoir stability
CN211500658U (en) Shallow tunnel supporting construction that nearly connects that buries suitable for sand ground
CN110259490A (en) A kind of Underground Subway Station construction method
CN114483109B (en) Curtain grouting advanced large pipe shed through construction method for crossing tunnel fault fracture zone
CN109518699A (en) Miniature steel pipe pile adds grid spray anchor deep foundation ditch combination supporting scheme system and its construction method
CN207003421U (en) A kind of steel plate pilework for being seated hard rock top surface
CN101838957A (en) Integral type T-shaped outer cantilever roads and construction method thereof
CN107489106A (en) A kind of rocky bed subaqueous bearing platform construction method
CN109898556A (en) A kind of underground pipe gallery structure and sunk type construction method
CN111101540B (en) Construction method for passing existing electric power tunnel on open cut tunnel
CN210068175U (en) A protective structure for preventing tunnel slip casting reinforcement from arousing earth's surface uplift
CN105926626B (en) Overlength pneumatic down hole hammer vibrates jet grouting pile construction technique
CN208917850U (en) A kind of miniature steel pipe pile adds grid to spray anchor deep foundation ditch combination supporting scheme system
CN102678127B (en) Method for constructing weakly consolidated non-stratified sandstone tunnel
CN110792440B (en) Construction method of water-rich loess tunnel penetrating through loess towards valley

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 20821973

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 20821973

Country of ref document: EP

Kind code of ref document: A1