CN110552704A - Construction method for underground excavation of water-rich sandy gravel stratum crossover section through urban main road - Google Patents
Construction method for underground excavation of water-rich sandy gravel stratum crossover section through urban main road Download PDFInfo
- Publication number
- CN110552704A CN110552704A CN201910871776.3A CN201910871776A CN110552704A CN 110552704 A CN110552704 A CN 110552704A CN 201910871776 A CN201910871776 A CN 201910871776A CN 110552704 A CN110552704 A CN 110552704A
- Authority
- CN
- China
- Prior art keywords
- section
- construction
- excavation
- grid
- pilot tunnel
- Prior art date
- Legal status (The legal status 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 status listed.)
- Granted
Links
- 238000010276 construction Methods 0.000 title claims abstract description 134
- 238000009412 basement excavation Methods 0.000 title claims abstract description 78
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 title claims abstract description 31
- 238000000034 method Methods 0.000 claims abstract description 67
- 238000006243 chemical reaction Methods 0.000 claims abstract description 51
- 230000002787 reinforcement Effects 0.000 claims abstract description 30
- 238000001556 precipitation Methods 0.000 claims abstract description 22
- 230000008569 process Effects 0.000 claims abstract description 13
- 229910000831 Steel Inorganic materials 0.000 claims description 55
- 239000010959 steel Substances 0.000 claims description 55
- 230000007704 transition Effects 0.000 claims description 38
- 238000005192 partition Methods 0.000 claims description 30
- 238000005553 drilling Methods 0.000 claims description 23
- 239000002689 soil Substances 0.000 claims description 22
- 239000011150 reinforced concrete Substances 0.000 claims description 19
- 239000002002 slurry Substances 0.000 claims description 17
- 238000012545 processing Methods 0.000 claims description 16
- 238000004088 simulation Methods 0.000 claims description 10
- 239000010410 layer Substances 0.000 claims description 8
- 238000003466 welding Methods 0.000 claims description 7
- 238000013461 design Methods 0.000 claims description 6
- 206010016807 Fluid retention Diseases 0.000 claims description 5
- 238000005452 bending Methods 0.000 claims description 5
- 239000004927 clay Substances 0.000 claims description 5
- 238000004140 cleaning Methods 0.000 claims description 5
- 238000010835 comparative analysis Methods 0.000 claims description 5
- 238000001914 filtration Methods 0.000 claims description 5
- 239000011229 interlayer Substances 0.000 claims description 5
- 239000000463 material Substances 0.000 claims description 5
- 238000005065 mining Methods 0.000 claims description 5
- 239000002245 particle Substances 0.000 claims description 5
- 238000009527 percussion Methods 0.000 claims description 5
- 238000004080 punching Methods 0.000 claims description 5
- 238000002360 preparation method Methods 0.000 abstract 1
- 230000000694 effects Effects 0.000 description 7
- 230000003014 reinforcing effect Effects 0.000 description 7
- 230000008901 benefit Effects 0.000 description 6
- 239000004567 concrete Substances 0.000 description 4
- 238000004519 manufacturing process Methods 0.000 description 4
- 239000004115 Sodium Silicate Substances 0.000 description 3
- 230000000903 blocking effect Effects 0.000 description 3
- 238000004364 calculation method Methods 0.000 description 3
- 230000008859 change Effects 0.000 description 3
- 239000004576 sand Substances 0.000 description 3
- 229910052911 sodium silicate Inorganic materials 0.000 description 3
- 239000004568 cement Substances 0.000 description 2
- 238000007796 conventional method Methods 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 238000003780 insertion Methods 0.000 description 2
- 230000037431 insertion Effects 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000005457 optimization Methods 0.000 description 2
- NTHWMYGWWRZVTN-UHFFFAOYSA-N sodium silicate Chemical compound [Na+].[Na+].[O-][Si]([O-])=O NTHWMYGWWRZVTN-UHFFFAOYSA-N 0.000 description 2
- 230000000007 visual effect Effects 0.000 description 2
- 239000002023 wood Substances 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000004891 communication Methods 0.000 description 1
- 238000012938 design process Methods 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
- 230000003068 static effect Effects 0.000 description 1
- 230000008961 swelling Effects 0.000 description 1
- 238000012546 transfer Methods 0.000 description 1
Classifications
-
- 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
-
- 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
- E21D9/00—Tunnels or galleries, with or without linings; Methods or apparatus for making thereof; Layout of tunnels or galleries
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21F—SAFETY DEVICES, TRANSPORT, FILLING-UP, RESCUE, VENTILATION, OR DRAINING IN OR OF MINES OR TUNNELS
- E21F16/00—Drainage
- E21F16/02—Drainage of tunnels
Landscapes
- Engineering & Computer Science (AREA)
- Mining & Mineral Resources (AREA)
- Life Sciences & Earth Sciences (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Geochemistry & Mineralogy (AREA)
- Geology (AREA)
- Architecture (AREA)
- Structural Engineering (AREA)
- Civil Engineering (AREA)
- Environmental & Geological Engineering (AREA)
- Excavating Of Shafts Or Tunnels (AREA)
Abstract
A construction method for passing through an urban main road by underground excavation at a water-rich sandy gravel stratum crossover section comprises the following steps: a. construction preparation, and precipitation construction is required before construction; b. carrying out stratum grouting reinforcement on the surrounding stratum of the crossover line section; c. carrying out underground excavation construction of the line crossing segment, and excavating the large section by adopting a double-side-wall pit guiding method; d. the underground excavation is carried out to the interrupted surface, and the double-side-wall pit guiding method is converted into the CRD method for excavation; e. and (5) carrying out underground excavation to a small section, and switching from a CRD method to a step method for excavation. The method of the invention overcomes the problems of loose structure of the water-rich sandy cobble stratum, poor stratum self-stability and large excavation risk, and strictly ensures the construction quality under the condition of ensuring safety. Meanwhile, different section conversion treatment measures are arranged at the conversion positions of different sections, all the processes are connected tightly, the settlement deformation of the whole section is controlled well, the construction period progress is fast, and the engineering cost is greatly reduced.
Description
Technical Field
The invention belongs to the rail transit equipment industry, relates to the technical field of underground structure engineering construction of urban rail transit vehicles, and particularly relates to a construction method for passing through an urban main road by underground excavation of a water-rich sandy gravel stratum crossover section.
background
along with the development and construction of urban underground space, the projects of urban underground loops, vehicle-driven communication channels, street-crossing underpasses and the like are increasingly increased, and particularly under the current domestic high-rise infrastructure environment, the construction condition of the special-shaped variable cross-section points of the undercut tunnels cannot be avoided.
Subway construction is generally located in busy urban areas, and urban main roads need to be crossed during construction, so that the main road safety is guaranteed as the key point of construction, and the requirement on pavement settlement control caused by construction is very strict. The construction of the crossover section has multiple section types, frequent conversion, multiple abrupt sections, large difference of section excavation profiles, and the large-amplitude abrupt section conversion cannot be completed by adopting conventional methods such as expanding excavation and reverse back excavation; when the section cross line section is constructed, the section types are more, and the conversion is frequent; and moreover, a plurality of abrupt sections exist, the difference of the excavation profiles of the sections is large, and the soil body is disturbed for a plurality of times during initial excavation, so that the settlement of the road and the upper pipeline is directly influenced. In addition, in the construction process, the sinking, the swelling and the collapse of the road surface are easily caused by tunnel collapse, water burst or deep hole grouting construction and the like; accidents such as sinking, uplifting and collapsing can have great influence on the traffic of the urban main road. In the construction process, production efficiency is directly influenced by overall arrangement, manpower transfer, section conversion, grouting quality and other links. Especially, the section conversion and grouting effect directly influence the pavement settlement control.
and if the subway construction is in a water-rich sandy gravel stratum, the excavation risk is large due to loose sandy gravel structure, large porosity, poor stratum self-stability and the like. How to ensure the construction quality and the safety of the crossover section becomes a difficult problem to be overcome urgently.
Disclosure of Invention
in order to solve the problems, the invention provides a construction method for passing through an urban trunk road by underground excavation at a water-rich sandy gravel stratum crossover section. The invention belongs to the rail transit equipment industry, and overcomes the problems of loose structure of water-rich sandy gravel stratum, poor stratum self-stability and large excavation risk, and strictly ensures the construction quality under the condition of ensuring safety. Meanwhile, the method of the invention sets different section conversion treatment measures at the conversion positions of different sections through rigorous and compact calculation, the working procedures are connected tightly, the settlement deformation of the whole section is controlled well, the construction period progress is fast, the method is suitable for sections with variable section sizes, the engineering cost is greatly reduced, and in addition, the stability and the safety of the conversion position of the whole section are fully ensured.
the invention adopts the technical scheme that the construction method for passing through the urban trunk road by underground excavation at the crossover section of the water-rich sandy gravel stratum comprises the following steps:
a. And (4) preparing for construction, wherein precipitation construction is required before construction, and the water level is reduced to 0.5-1m below the structural floor. And the interlayer retention water is treated clearly and in time to ensure the construction safety;
b. Carrying out stratum grouting reinforcement on the surrounding stratum of the crossover line section, after the stratum grouting reinforcement is finished, erecting a temporary steel support at the crossover line section, and then building an arched pipe shed and carrying out pipe shed grouting reinforcement;
c. carrying out underground excavation construction of the line crossing section, and excavating the large section by adopting a double-side-wall pit guiding method: excavating an upper step of the pilot tunnel, constructing a primary support of the upper step of the pilot tunnel, constructing a temporary support of the side wall of the upper step of the pilot tunnel, and if necessary, arranging a temporary inverted arch of the upper step of the pilot tunnel; excavating a lower step of the pilot tunnel, constructing a primary support of the lower step of the pilot tunnel, and constructing a temporary support of the side wall of the lower step of the pilot tunnel; excavating an upper step of the backward heading, primarily supporting the upper step of the backward heading after construction, temporarily supporting the side wall of the upper step of the backward heading, and if necessary, arranging a temporary inverted arch of the upper step of the backward heading; excavating a following pilot tunnel lower step, primarily supporting the following pilot tunnel lower step after construction, and temporarily supporting the side wall of the following pilot tunnel lower step after construction; reserving core soil at the arch part of the upper step of the middle tunnel, and reserving a primary support of the core soil at the arch part of the middle tunnel during construction; excavating middle step reserved core soil of the middle tunnel and lower step reserved core soil of the middle tunnel, and constructing an inverted arch primary support of the middle tunnel; dismantling all temporary supports, and constructing an inverted arch and an arch wall secondary lining;
d. And (3) carrying out subsurface excavation to the interrupted surface, and switching from a double-side-wall pit guiding method to a CRD method for excavation: excavating an upper step of the pilot tunnel, constructing a primary support of the upper step of the pilot tunnel, and constructing a temporary support of a middle partition wall of the upper step and a temporary inverted arch of the upper step of the pilot tunnel; excavating a lower step of the pilot tunnel, constructing a primary support of the lower step of the pilot tunnel, and constructing a temporary support of a middle partition wall of the lower step; excavating a backward guide pit upper step, primarily supporting the backward guide pit upper step, and constructing a backward guide pit lower step temporary inverted arch; excavating a backward pilot tunnel lower step, and primarily supporting the backward pilot tunnel lower step; dismantling the temporary support of the middle partition wall of the upper step and the temporary support of the middle partition wall of the lower step, and constructing an inverted arch and an arch wall for secondary lining; when the double-side-wall temporary inverted arch is converted, the left middle partition wall of the double side walls moves leftwards to be overlapped with the CRD middle partition wall, and the upper and lower step temporary inverted arches of the double side walls move downwards to be overlapped with the upper and lower step temporary inverted arches of the CRD;
e. And (3) carrying out underground excavation to a small section, and converting the underground excavation into excavation by a step method through a CRD method: and excavating and supporting the upper step and the lower step.
preferably, each construction method is provided with a section transition area during conversion, the primary lining width of the section transition area is 2000-4000mm, grids are arranged at the section transition area and the section conversion position, the grid processing of the section transition area is performed according to the interval of 360-380mm, the grids are lofted one by one, the grids are formed by welding after cold bending forming by steel bars, and the sections have two forms consisting of 3 and 4 main bars; the diameter of the main rib is 25-30mm, and the height of the section is 150-160 mm; the main reinforcement is connected with a contact steel bar, the diameter of the contact steel bar is 15-20mm, and the contact steel bar is welded at the end part of the main reinforcement by a connecting plate; trial assembly is carried out after the grid is machined, and all unit elements of the grid are connected through mining bolts.
In any of the above schemes, preferably, the upper part of the grid at the section transition is processed by I25b I-shaped steel, and the top width of the primary lining at the section transition is properly expanded according to the height of the section steel; the grid is divided into 25 units for processing, and steel plates with the width of 25mm and the thickness of 10mm are welded on the outer sides of the middle plate and the bottom plate of the grid; the grid of section conversion department is the shaped steel material, and the grid of section transition zone perpendicular to section axle center is encrypted and is arranged, adopts welded connection with the grid of section conversion department.
In any of the above schemes, preferably, the precipitation construction comprises the following specific steps: checking the position of the dewatering well, excavating after confirming that no fault exists, and burying a wall protecting pipe; after the wall protecting pipe is buried, a percussion drill is used for punching and drilling holes, and meanwhile, slurry is used for protecting the wall, so that the height of slurry in the holes is kept, the holes are prevented from collapsing, and the holes are formed when the drilling depth reaches a designed value; vertically putting a reinforced concrete well pipe after hole forming; filling gravels into the precipitation well with the reinforced concrete well pipe fixed, and forming a filtering layer for precipitation; cleaning the dewatering well, and filling clay to seal the well.
In any of the above schemes, preferably, the bore diameter of the borehole is 610-620mm, the inner diameter of the reinforced concrete well pipe is 300mm, the outer diameter is 400mm, and the particle size of the gravel is 5-6 mm.
In any of the above schemes, preferably, the circumferential distance of the arched pipe sheds is 0.5-0.6 m, and the arched variable-section tunnels are surrounded by the pipe sheds; the length of a single section of the arched pipe shed is 4m or 2m, and the pipe sheds are overlapped in a staggered mode through staggered use.
In any of the above aspects, preferably, the determination of the grid form is specifically: establishing a grid model design by using BIM, optimizing grid formats according to different section sizes and excavation modes, and performing simulation comparative analysis to form an effective model; and a finite element simulation construction process is adopted to predict the surface subsidence, and a pertinence measure for reducing subsidence is formulated by combining a prediction conclusion, so that a grid form is determined.
In the method, each construction step and the form of the primary support grating of the transition line section are optimized, including reduction of the blocking removal range, optimization of the form of the variable-section grating, control of grouting parameters and the like, technical countermeasures and management measures are researched and made, and then field experiments and adjustment measures are carried out to determine the final control method.
The invention is obtained according to years of practical application practice and experience, adopts the best technical means and measures to carry out combined optimization, obtains the optimal technical effect, is not simple superposition and splicing of technical characteristics, and has obvious significance.
the invention has the beneficial effects that:
1. The method of the invention overcomes the problems of loose structure of the water-rich sandy cobble stratum, poor stratum self-stability and large excavation risk, and strictly ensures the construction quality under the condition of ensuring safety. Meanwhile, the method of the invention sets different section conversion treatment measures at the conversion positions of different sections through rigorous and compact calculation, the working procedures are connected tightly, the settlement deformation of the whole section is controlled well, the construction period progress is fast, the method is suitable for sections with variable section sizes, the engineering cost is greatly reduced, and in addition, the stability and the safety of the conversion position of the whole section are fully ensured.
2. the invention optimizes the excavation mode of the transition section between different excavation methods, realizes reasonable control from various aspects of safety, quality, production efficiency and the like, and has remarkable economic and social benefits.
3. by arranging the interval transition section, the invention has frequent conversion and a plurality of abrupt cross-section grating connection forms, thereby reducing the blocking removal range, enabling the stratum settlement control to be more effective and reducing the influence of construction on the surrounding environment.
4. The invention improves and innovates the traditional construction method of section conversion, and does not eliminate the potential safety hazard of the traditional method; the construction method has the advantages of simple process, reasonable measures, strong construction safety and stability, strong adaptability and better social and economic benefits, and the ground surface settlement and the tunnel deformation can be effectively controlled.
Drawings
FIG. 1 is a construction flow chart of the construction method for crossing urban main roads by underground excavation of a cross section of a water-rich sandy gravel stratum according to the invention.
Detailed Description
The invention is further described with reference to the following figures and specific examples, but the scope of the claims is not limited thereto.
Example 1
And (5) constructing a subway station in a central area of a certain northern city. The subway station is located in a busy city section, and needs to go down to cross a city trunk road during construction. A transition line segment is arranged at the west end of the interval, the section types are many, and the conversion is frequent; and moreover, a plurality of abrupt sections exist, the difference of the excavation profiles of the sections is large, the conventional method cannot complete large-amplitude abrupt section conversion, the maximum section is 15m multiplied by 12m, and the distance between the maximum section and the adjacent standard section is only 2.3 m. The main structure of the interval is mainly positioned on a medium-coarse sand layer, a fine sand layer and a pebble-round gravel layer, and the settlement of the road and the upper pipeline can be directly influenced by disturbing the soil body for multiple times during initial excavation.
Therefore, the construction method for crossing the urban arterial road by underground excavation of the water-rich sandy gravel stratum cross line segment is finally determined by a multi-way scheme. As shown in fig. 1, the method comprises the steps of:
a. And (4) preparing for construction, wherein precipitation construction is required before construction, and the water level is reduced to 0.5-1m below the structural floor. And the interlayer retention water is treated clearly and in time to ensure the construction safety;
b. Carrying out stratum grouting reinforcement on the surrounding stratum of the crossover line section, after the stratum grouting reinforcement is finished, erecting a temporary steel support at the crossover line section, and then building an arched pipe shed and carrying out pipe shed grouting reinforcement;
c. Carrying out underground excavation construction of the line crossing section, and excavating the large section by adopting a double-side-wall pit guiding method: excavating an upper step of the pilot tunnel, constructing a primary support of the upper step of the pilot tunnel, constructing a temporary support of the side wall of the upper step of the pilot tunnel, and if necessary, arranging a temporary inverted arch of the upper step of the pilot tunnel; excavating a lower step of the pilot tunnel, constructing a primary support of the lower step of the pilot tunnel, and constructing a temporary support of the side wall of the lower step of the pilot tunnel; excavating an upper step of the backward heading, primarily supporting the upper step of the backward heading after construction, temporarily supporting the side wall of the upper step of the backward heading, and if necessary, arranging a temporary inverted arch of the upper step of the backward heading; excavating a following pilot tunnel lower step, primarily supporting the following pilot tunnel lower step after construction, and temporarily supporting the side wall of the following pilot tunnel lower step after construction; reserving core soil at the arch part of the upper step of the middle tunnel, and reserving a primary support of the core soil at the arch part of the middle tunnel during construction; excavating middle step reserved core soil of the middle tunnel and lower step reserved core soil of the middle tunnel, and constructing an inverted arch primary support of the middle tunnel; dismantling all temporary supports, and constructing an inverted arch and an arch wall secondary lining;
d. And (3) carrying out subsurface excavation to the interrupted surface, and switching from a double-side-wall pit guiding method to a CRD method for excavation: excavating an upper step of the pilot tunnel, constructing a primary support of the upper step of the pilot tunnel, and constructing a temporary support of a middle partition wall of the upper step and a temporary inverted arch of the upper step of the pilot tunnel; excavating a lower step of the pilot tunnel, constructing a primary support of the lower step of the pilot tunnel, and constructing a temporary support of a middle partition wall of the lower step; excavating a backward guide pit upper step, primarily supporting the backward guide pit upper step, and constructing a backward guide pit lower step temporary inverted arch; excavating a backward pilot tunnel lower step, and primarily supporting the backward pilot tunnel lower step; dismantling the temporary support of the middle partition wall of the upper step and the temporary support of the middle partition wall of the lower step, and constructing an inverted arch and an arch wall for secondary lining; when the double-side-wall temporary inverted arch is converted, the left middle partition wall of the double side walls moves leftwards to be overlapped with the CRD middle partition wall, and the upper and lower step temporary inverted arches of the double side walls move downwards to be overlapped with the upper and lower step temporary inverted arches of the CRD;
e. And (3) carrying out underground excavation to a small section, and converting the underground excavation into excavation by a step method through a CRD method: and excavating and supporting the upper step and the lower step.
the construction method comprises the steps that a section transition area is arranged during conversion, the primary lining width of the section transition area is 2000-4000mm, grids are arranged in the section transition area and the section conversion position, grid processing of the section transition area is performed according to the distance of 360-380mm, roof lofting processing is performed one by one, the grids are formed by welding after cold bending forming of steel bars, and the sections are formed by 3 and 4 main bars; the diameter of the main rib is 25-30mm, and the height of the section is 150-160 mm; the main reinforcement is connected with a contact steel bar, the diameter of the contact steel bar is 15-20mm, and the contact steel bar is welded at the end part of the main reinforcement by a connecting plate; trial assembly is carried out after the grid is machined, and all unit elements of the grid are connected through mining bolts.
the upper part of the grid at the section conversion part is processed by I25b I-shaped steel, and the top width of the primary lining at the section conversion part is properly expanded according to the height of the section steel; the grid is divided into 25 units for processing, and steel plates with the width of 25mm and the thickness of 10mm are welded on the outer sides of the middle plate and the bottom plate of the grid; the grid of section conversion department is the shaped steel material, and the grid of section transition zone perpendicular to section axle center is encrypted and is arranged, adopts welded connection with the grid of section conversion department.
the concrete steps of precipitation construction are as follows: checking the position of the dewatering well, excavating after confirming that no fault exists, and burying a wall protecting pipe; after the wall protecting pipe is buried, a percussion drill is used for punching and drilling holes, and meanwhile, slurry is used for protecting the wall, so that the height of slurry in the holes is kept, the holes are prevented from collapsing, and the holes are formed when the drilling depth reaches a designed value; vertically putting a reinforced concrete well pipe after hole forming; filling gravels into the precipitation well with the reinforced concrete well pipe fixed, and forming a filtering layer for precipitation; cleaning the dewatering well, and filling clay to seal the well.
The bore diameter of the drill hole is 610-620mm, the inner diameter of the reinforced concrete well pipe is 300mm, the outer diameter of the reinforced concrete well pipe is 400mm, and the particle size of the gravel is 5-6 mm.
The annular space of the arched pipe shed is 0.5-0.6 m, and the arched variable-section tunnel is surrounded by the pipe shed; the length of a single section of the arched pipe shed is 4m or 2m, and the pipe sheds are overlapped in a staggered mode through staggered use.
The determination of the grid form is specifically as follows: establishing a grid model design by using BIM, optimizing grid formats according to different section sizes and excavation modes, and performing simulation comparative analysis to form an effective model; and a finite element simulation construction process is adopted to predict the surface subsidence, and a pertinence measure for reducing subsidence is formulated by combining a prediction conclusion, so that a grid form is determined.
Example 2
A construction method for passing through main city roads by underground excavation at a crossover section of a water-rich sandy gravel stratum. As shown in fig. 1, the method comprises the steps of:
a. And (4) preparing for construction, wherein precipitation construction is required before construction, and the water level is reduced to 0.5-1m below the structural floor. And the interlayer retention water is treated clearly and in time to ensure the construction safety;
b. carrying out stratum grouting reinforcement on the surrounding stratum of the crossover line section, after the stratum grouting reinforcement is finished, erecting a temporary steel support at the crossover line section, and then building an arched pipe shed and carrying out pipe shed grouting reinforcement;
c. Carrying out underground excavation construction of the line crossing section, and excavating the large section by adopting a double-side-wall pit guiding method: excavating an upper step of the pilot tunnel, constructing a primary support of the upper step of the pilot tunnel, constructing a temporary support of the side wall of the upper step of the pilot tunnel, and if necessary, arranging a temporary inverted arch of the upper step of the pilot tunnel; excavating a lower step of the pilot tunnel, constructing a primary support of the lower step of the pilot tunnel, and constructing a temporary support of the side wall of the lower step of the pilot tunnel; excavating an upper step of the backward heading, primarily supporting the upper step of the backward heading after construction, temporarily supporting the side wall of the upper step of the backward heading, and if necessary, arranging a temporary inverted arch of the upper step of the backward heading; excavating a following pilot tunnel lower step, primarily supporting the following pilot tunnel lower step after construction, and temporarily supporting the side wall of the following pilot tunnel lower step after construction; reserving core soil at the arch part of the upper step of the middle tunnel, and reserving a primary support of the core soil at the arch part of the middle tunnel during construction; excavating middle step reserved core soil of the middle tunnel and lower step reserved core soil of the middle tunnel, and constructing an inverted arch primary support of the middle tunnel; dismantling all temporary supports, and constructing an inverted arch and an arch wall secondary lining;
d. and (3) carrying out subsurface excavation to the interrupted surface, and switching from a double-side-wall pit guiding method to a CRD method for excavation: excavating an upper step of the pilot tunnel, constructing a primary support of the upper step of the pilot tunnel, and constructing a temporary support of a middle partition wall of the upper step and a temporary inverted arch of the upper step of the pilot tunnel; excavating a lower step of the pilot tunnel, constructing a primary support of the lower step of the pilot tunnel, and constructing a temporary support of a middle partition wall of the lower step; excavating a backward guide pit upper step, primarily supporting the backward guide pit upper step, and constructing a backward guide pit lower step temporary inverted arch; excavating a backward pilot tunnel lower step, and primarily supporting the backward pilot tunnel lower step; dismantling the temporary support of the middle partition wall of the upper step and the temporary support of the middle partition wall of the lower step, and constructing an inverted arch and an arch wall for secondary lining; when the double-side-wall temporary inverted arch is converted, the left middle partition wall of the double side walls moves leftwards to be overlapped with the CRD middle partition wall, and the upper and lower step temporary inverted arches of the double side walls move downwards to be overlapped with the upper and lower step temporary inverted arches of the CRD;
e. And (3) carrying out underground excavation to a small section, and converting the underground excavation into excavation by a step method through a CRD method: and excavating and supporting the upper step and the lower step.
The construction method comprises the steps that a section transition area is arranged during conversion, the primary lining width of the section transition area is 2000-4000mm, grids are arranged in the section transition area and the section conversion position, grid processing of the section transition area is performed according to the distance of 360-380mm, roof lofting processing is performed one by one, the grids are formed by welding after cold bending forming of steel bars, and the sections are formed by 3 and 4 main bars; the diameter of the main rib is 25-30mm, and the height of the section is 150-160 mm; the main reinforcement is connected with a contact steel bar, the diameter of the contact steel bar is 15-20mm, and the contact steel bar is welded at the end part of the main reinforcement by a connecting plate; trial assembly is carried out after the grid is machined, and all unit elements of the grid are connected through mining bolts.
The upper part of the grid at the section conversion part is processed by I25b I-shaped steel, and the top width of the primary lining at the section conversion part is properly expanded according to the height of the section steel; the grid is divided into 25 units for processing, and steel plates with the width of 25mm and the thickness of 10mm are welded on the outer sides of the middle plate and the bottom plate of the grid; the grid of section conversion department is the shaped steel material, and the grid of section transition zone perpendicular to section axle center is encrypted and is arranged, adopts welded connection with the grid of section conversion department.
The concrete steps of precipitation construction are as follows: checking the position of the dewatering well, excavating after confirming that no fault exists, and burying a wall protecting pipe; after the wall protecting pipe is buried, a percussion drill is used for punching and drilling holes, and meanwhile, slurry is used for protecting the wall, so that the height of slurry in the holes is kept, the holes are prevented from collapsing, and the holes are formed when the drilling depth reaches a designed value; vertically putting a reinforced concrete well pipe after hole forming; filling gravels into the precipitation well with the reinforced concrete well pipe fixed, and forming a filtering layer for precipitation; cleaning the dewatering well, and filling clay to seal the well.
The bore diameter of the drill hole is 610-620mm, the inner diameter of the reinforced concrete well pipe is 300mm, the outer diameter of the reinforced concrete well pipe is 400mm, and the particle size of the gravel is 5-6 mm.
The annular space of the arched pipe shed is 0.5-0.6 m, and the arched variable-section tunnel is surrounded by the pipe shed; the length of a single section of the arched pipe shed is 4m or 2m, and the pipe sheds are overlapped in a staggered mode through staggered use.
The determination of the grid form is specifically as follows: establishing a grid model design by using BIM, optimizing grid formats according to different section sizes and excavation modes, and performing simulation comparative analysis to form an effective model; and a finite element simulation construction process is adopted to predict the surface subsidence, and a pertinence measure for reducing subsidence is formulated by combining a prediction conclusion, so that a grid form is determined.
in addition, in order to further improve the construction effect, the concrete steps of grouting reinforcement in the step b are as follows:
(1) processing a phi 108 multiplied by 6mm seamless steel pipe into pipe sections with three specifications of single length of 1.5m, 1.0m and 0.5m, respectively processing locking pieces for connection at two ends of the pipe sections, and processing a plurality of phi 15-20mm grouting holes on the pipe wall of the pipe sections;
(2) accurately measuring the hole position of a drill hole for installing a guide pipe, and drilling a guide hole by using a water drill before formal drilling construction;
(3) sequentially building a scaffold by using steel pipes from bottom to top and from two sides to the middle according to hole positions, and paving the upper surface by using a wood plate;
(4) Placing a drilling machine on a wood board of a scaffold, adjusting the height and the angle, fixing the drilling machine, and checking whether each pipeline and each connecting piece are correct or not;
(5) A drill bit and a drill rod of the drilling machine penetrate through the guide pipe, are aligned to the marked hole site hole center, and are used for straight drilling, and the inclination of the hole is controlled through the guide of the guide pipe to form a drilled hole;
(6) Connecting a plurality of pipe sections into a guide pipe through a locking piece for later use, immediately jacking the guide pipe corresponding to the drilled hole into the hole by using a drilling machine after the drilling is finished, and removing the drilling machine to drill the next hole after the guide pipe is installed;
(7) after the guide pipe is installed, adopting the slurry of cement-sodium silicate double slurry to carry out forward grouting at the grouting pressure of 0.6-0.8 MPa; the weight ratio of the cement slurry to the sodium silicate slurry in the slurry is 1: 1; the mass ratio of water to ash in the cement slurry is 1: 1; the baume degree of the sodium silicate slurry is 28-30 Be.
The grouting reinforcement method strictly controls the drilling process according to the structural characteristics of the water-rich sandy gravel stratum, and controls the safety and construction quality of underground excavation construction from multiple aspects; the self-arching effect of the pipe shed is combined with the self-stability performance of the sand and pebbles under the precipitation condition, so that a relatively ideal reinforcing effect is achieved; the method has little disturbance to the ground and little later settlement on the ground.
In addition, a reinforcing measure is arranged at the section conversion part, and the reinforcing measure specifically comprises the following steps: excavating a larger section at the section conversion part to serve as a primary support of the tunnel, and determining a pipe shed construction position according to the distance between the tunnel with the smaller section and the tunnel face and the pipe shed construction angle; drilling holes at proper positions of the vault of the tunnel with the larger cross section to form a pipe shed, wherein the insertion angle of the pipe shed is 1-2 degrees, and the steel pipes of the pipe shed are seamless steel pipes with the diameter of 108mm and the wall thickness of 6mm and are installed in sections; grouting the inside of the pipe, and after the advance grouting reinforcement of the pipe shed is finished, continuously excavating a tunnel face to erect a steel frame grid at the construction position of the pipe shed and welding the steel frame grid with the pipe shed; drilling a hole at a proper position of the arch crown of the tunnel with the larger cross section to form a small advanced guide pipe, wherein the insertion angle of the small advanced guide pipe is 1-2 degrees, and the small advanced guide pipe is arranged at a cross section conversion position; after the advance small guide pipe grouting reinforcement is completed, continuously excavating a tunnel face, erecting a steel frame grid at the position where the advance small guide pipe is constructed, and welding the steel frame grid with the advance small guide pipe; and (3) constructing a tunnel with a larger cross section to a variable cross section, drilling a deep hole grouting pipe according to stratum conditions, grouting and reinforcing, and occluding with a pipe shed and an advanced small guide pipe reinforcing range to ensure the safety of the tunnel with the smaller cross section.
the small advanced guide pipe is a grouting steel perforated pipe; the deep hole grouting pipe is a grouting PVC pipe. The pipe shed is welded and fixed with the steel frame of the primary tunnel support, and the advanced small conduit is welded and fixed with the steel frame of the primary tunnel support. The deep hole grouting pipes are arranged at intervals of 600-700 mm.
The reinforcing measure can meet the related functional requirements of general stratum underground excavation, ensure the safe construction of the underground excavation, and simultaneously enlarge the stratum reinforcing area to have less influence on the ground and the surrounding important buildings. Therefore, the problems of difficulty in underground excavation construction and poor effect are solved, and the underground excavation construction method has wide application value in the construction fields of urban subway tunnels and the like.
Example 3
a construction method for passing through main city roads by underground excavation at a crossover section of a water-rich sandy gravel stratum. As shown in fig. 1, the method comprises the steps of:
a. and (4) preparing for construction, wherein precipitation construction is required before construction, and the water level is reduced to 0.5-1m below the structural floor. And the interlayer retention water is treated clearly and in time to ensure the construction safety;
b. Carrying out stratum grouting reinforcement on the surrounding stratum of the crossover line section, after the stratum grouting reinforcement is finished, erecting a temporary steel support at the crossover line section, and then building an arched pipe shed and carrying out pipe shed grouting reinforcement;
c. Carrying out underground excavation construction of the line crossing section, and excavating the large section by adopting a double-side-wall pit guiding method: excavating an upper step of the pilot tunnel, constructing a primary support of the upper step of the pilot tunnel, constructing a temporary support of the side wall of the upper step of the pilot tunnel, and if necessary, arranging a temporary inverted arch of the upper step of the pilot tunnel; excavating a lower step of the pilot tunnel, constructing a primary support of the lower step of the pilot tunnel, and constructing a temporary support of the side wall of the lower step of the pilot tunnel; excavating an upper step of the backward heading, primarily supporting the upper step of the backward heading after construction, temporarily supporting the side wall of the upper step of the backward heading, and if necessary, arranging a temporary inverted arch of the upper step of the backward heading; excavating a following pilot tunnel lower step, primarily supporting the following pilot tunnel lower step after construction, and temporarily supporting the side wall of the following pilot tunnel lower step after construction; reserving core soil at the arch part of the upper step of the middle tunnel, and reserving a primary support of the core soil at the arch part of the middle tunnel during construction; excavating middle step reserved core soil of the middle tunnel and lower step reserved core soil of the middle tunnel, and constructing an inverted arch primary support of the middle tunnel; dismantling all temporary supports, and constructing an inverted arch and an arch wall secondary lining;
d. And (3) carrying out subsurface excavation to the interrupted surface, and switching from a double-side-wall pit guiding method to a CRD method for excavation: excavating an upper step of the pilot tunnel, constructing a primary support of the upper step of the pilot tunnel, and constructing a temporary support of a middle partition wall of the upper step and a temporary inverted arch of the upper step of the pilot tunnel; excavating a lower step of the pilot tunnel, constructing a primary support of the lower step of the pilot tunnel, and constructing a temporary support of a middle partition wall of the lower step; excavating a backward guide pit upper step, primarily supporting the backward guide pit upper step, and constructing a backward guide pit lower step temporary inverted arch; excavating a backward pilot tunnel lower step, and primarily supporting the backward pilot tunnel lower step; dismantling the temporary support of the middle partition wall of the upper step and the temporary support of the middle partition wall of the lower step, and constructing an inverted arch and an arch wall for secondary lining; when the double-side-wall temporary inverted arch is converted, the left middle partition wall of the double side walls moves leftwards to be overlapped with the CRD middle partition wall, and the upper and lower step temporary inverted arches of the double side walls move downwards to be overlapped with the upper and lower step temporary inverted arches of the CRD;
e. and (3) carrying out underground excavation to a small section, and converting the underground excavation into excavation by a step method through a CRD method: and excavating and supporting the upper step and the lower step.
the construction method comprises the steps that a section transition area is arranged during conversion, the primary lining width of the section transition area is 2000-4000mm, grids are arranged in the section transition area and the section conversion position, grid processing of the section transition area is performed according to the distance of 360-380mm, roof lofting processing is performed one by one, the grids are formed by welding after cold bending forming of steel bars, and the sections are formed by 3 and 4 main bars; the diameter of the main rib is 25-30mm, and the height of the section is 150-160 mm; the main reinforcement is connected with a contact steel bar, the diameter of the contact steel bar is 15-20mm, and the contact steel bar is welded at the end part of the main reinforcement by a connecting plate; trial assembly is carried out after the grid is machined, and all unit elements of the grid are connected through mining bolts.
the upper part of the grid at the section conversion part is processed by I25b I-shaped steel, and the top width of the primary lining at the section conversion part is properly expanded according to the height of the section steel; the grid is divided into 25 units for processing, and steel plates with the width of 25mm and the thickness of 10mm are welded on the outer sides of the middle plate and the bottom plate of the grid; the grid of section conversion department is the shaped steel material, and the grid of section transition zone perpendicular to section axle center is encrypted and is arranged, adopts welded connection with the grid of section conversion department.
the concrete steps of precipitation construction are as follows: checking the position of the dewatering well, excavating after confirming that no fault exists, and burying a wall protecting pipe; after the wall protecting pipe is buried, a percussion drill is used for punching and drilling holes, and meanwhile, slurry is used for protecting the wall, so that the height of slurry in the holes is kept, the holes are prevented from collapsing, and the holes are formed when the drilling depth reaches a designed value; vertically putting a reinforced concrete well pipe after hole forming; filling gravels into the precipitation well with the reinforced concrete well pipe fixed, and forming a filtering layer for precipitation; cleaning the dewatering well, and filling clay to seal the well.
The bore diameter of the drill hole is 610-620mm, the inner diameter of the reinforced concrete well pipe is 300mm, the outer diameter of the reinforced concrete well pipe is 400mm, and the particle size of the gravel is 5-6 mm.
The annular space of the arched pipe shed is 0.5-0.6 m, and the arched variable-section tunnel is surrounded by the pipe shed; the length of a single section of the arched pipe shed is 4m or 2m, and the pipe sheds are overlapped in a staggered mode through staggered use.
the determination of the grid form is specifically as follows: establishing a grid model design by using BIM, optimizing grid formats according to different section sizes and excavation modes, and performing simulation comparative analysis to form an effective model; and a finite element simulation construction process is adopted to predict the surface subsidence, and a pertinence measure for reducing subsidence is formulated by combining a prediction conclusion, so that a grid form is determined.
in addition, in order to further improve the construction effect, the step of determining the grid form further comprises the following steps:
S1, establishing different section sizes of the initial grating according to the support conventional shape of the tunnel, establishing a three-dimensional static and dynamic numerical model by using a finite element program, calculating and simulating a construction process, predicting surface subsidence, and formulating a pertinence measure for reducing subsidence by combining a prediction conclusion so as to determine the form of the grating; and taking the different section sizes of the initial grating as the basic input conditions during the manufacturing process of the whole grating.
S2, determining a plane where the center line of the grating is located according to different section sizes, grating models, longitudinal intervals of the grating and excavation modes where the initial grating is located, and finally obtaining the three-dimensional center line of the grating.
And S3, dividing the main framework, the node framework, the longitudinal connecting rib framework and the locking pin anchor pipe framework of the grating by using a program language in an auxiliary manner according to the center line, the model number, the node type and the node size of the grating, and setting corresponding parameters according to the common size to facilitate subsequent change and adjustment.
And S4, establishing a model, a node model, a longitudinal connecting rib model and a locking pin anchor pipe model of the grid main body by combining the grid form, and setting corresponding parameters according to the common size to facilitate subsequent change and adjustment.
And S5, generating all input condition elements of the model in the step S4 by using a program language based on the framework generated in the step S3.
S6, instantiating each model created in the step S4 to each framework position generated in the step S3 respectively by using the program language and the input condition elements generated in the step S5;
And S7, integrating the results generated in all the steps to create an integral model, wherein the input conditions of the model are different section sizes of the spatial lines and the initial grids.
And S8, selecting the three-dimensional space lines under different working conditions and different section sizes of the three-dimensional initial grids as input conditions, instantiating an integral template, and updating the parameters in the steps S3 and S4 after correspondingly adjusting the parameters to finish the final effective model.
Based on the three-dimensional BIM model and the three-dimensional space linear position, the grid BIM model is quickly established in the three-dimensional mode, the design process is accurate, visual and efficient, the requirements of grid three-dimensional visual intersection bottoms and construction precision under different section sizes can be met, the BIM design concept of the tunnel grid is met, and the application of the BIM technology in tunnel engineering is promoted. The method has high automation degree and strong practicability and has obvious popularization and application values.
the construction process is simulated by adopting finite elements, the surface subsidence is predicted, the pertinence measure for reducing subsidence is made by combining the prediction conclusion, the grid form is determined, the theoretical support is achieved, and the construction reliability is improved; and an informatization construction technology is adopted, the measurement information is fed back to the construction in time, the construction scheme and the construction parameters are adjusted in time, and the construction safety is guaranteed.
In addition, in order to achieve better technical effects, the technical solutions in the above embodiments may be combined arbitrarily to meet various requirements of practical applications.
According to the embodiment, the method disclosed by the invention overcomes the problems of loose structure of the water-rich sandy gravel stratum, poor stratum self-stability and large excavation risk, and strictly ensures the construction quality under the condition of ensuring safety. Meanwhile, the method of the invention sets different section conversion treatment measures at the conversion positions of different sections through rigorous and compact calculation, the working procedures are connected tightly, the settlement deformation of the whole section is controlled well, the construction period progress is fast, the method is suitable for sections with variable section sizes, the engineering cost is greatly reduced, and in addition, the stability and the safety of the conversion position of the whole section are fully ensured.
the invention optimizes the excavation mode of the transition section between different excavation methods, realizes reasonable control from various aspects of safety, quality, production efficiency and the like, and has remarkable economic and social benefits.
By arranging the interval transition section, the invention has frequent conversion and a plurality of abrupt cross-section grating connection forms, thereby reducing the blocking removal range, enabling the stratum settlement control to be more effective and reducing the influence of construction on the surrounding environment.
The invention improves and innovates the traditional construction method of section conversion, and does not eliminate the potential safety hazard of the traditional method; the construction method has the advantages of simple process, reasonable measures, strong construction safety and stability, strong adaptability and better social and economic benefits, and the ground surface settlement and the tunnel deformation can be effectively controlled.
The foregoing is directed to preferred embodiments of the present invention, other and further embodiments of the invention may be devised without departing from the basic scope thereof, and the scope thereof is determined by the claims that follow. However, any simple modification, equivalent change and modification of the above embodiments according to the technical essence of the present invention are within the protection scope of the technical solution of the present invention.
Claims (7)
1. A construction method for underground excavation of a water-rich sandy gravel stratum crossover section to pass through an urban main road is characterized by comprising the following steps:
a. And (4) preparing for construction, wherein precipitation construction is required before construction, and the water level is reduced to 0.5-1m below the structural floor. And the interlayer retention water is treated clearly and in time to ensure the construction safety;
b. Carrying out stratum grouting reinforcement on the surrounding stratum of the crossover line section, after the stratum grouting reinforcement is finished, erecting a temporary steel support at the crossover line section, and then building an arched pipe shed and carrying out pipe shed grouting reinforcement;
c. Carrying out underground excavation construction of the line crossing section, and excavating the large section by adopting a double-side-wall pit guiding method: excavating an upper step of the pilot tunnel, constructing a primary support of the upper step of the pilot tunnel, constructing a temporary support of the side wall of the upper step of the pilot tunnel, and if necessary, arranging a temporary inverted arch of the upper step of the pilot tunnel; excavating a lower step of the pilot tunnel, constructing a primary support of the lower step of the pilot tunnel, and constructing a temporary support of the side wall of the lower step of the pilot tunnel; excavating an upper step of the backward heading, primarily supporting the upper step of the backward heading after construction, temporarily supporting the side wall of the upper step of the backward heading, and if necessary, arranging a temporary inverted arch of the upper step of the backward heading; excavating a following pilot tunnel lower step, primarily supporting the following pilot tunnel lower step after construction, and temporarily supporting the side wall of the following pilot tunnel lower step after construction; reserving core soil at the arch part of the upper step of the middle tunnel, and reserving a primary support of the core soil at the arch part of the middle tunnel during construction; excavating middle step reserved core soil of the middle tunnel and lower step reserved core soil of the middle tunnel, and constructing an inverted arch primary support of the middle tunnel; dismantling all temporary supports, and constructing an inverted arch and an arch wall secondary lining;
d. And (3) carrying out subsurface excavation to the interrupted surface, and switching from a double-side-wall pit guiding method to a CRD method for excavation: excavating an upper step of the pilot tunnel, constructing a primary support of the upper step of the pilot tunnel, and constructing a temporary support of a middle partition wall of the upper step and a temporary inverted arch of the upper step of the pilot tunnel; excavating a lower step of the pilot tunnel, constructing a primary support of the lower step of the pilot tunnel, and constructing a temporary support of a middle partition wall of the lower step; excavating a backward guide pit upper step, primarily supporting the backward guide pit upper step, and constructing a backward guide pit lower step temporary inverted arch; excavating a backward pilot tunnel lower step, and primarily supporting the backward pilot tunnel lower step; dismantling the temporary support of the middle partition wall of the upper step and the temporary support of the middle partition wall of the lower step, and constructing an inverted arch and an arch wall for secondary lining; when the double-side-wall temporary inverted arch is converted, the left middle partition wall of the double side walls moves leftwards to be overlapped with the CRD middle partition wall, and the upper and lower step temporary inverted arches of the double side walls move downwards to be overlapped with the upper and lower step temporary inverted arches of the CRD;
e. And (3) carrying out underground excavation to a small section, and converting the underground excavation into excavation by a step method through a CRD method: and excavating and supporting the upper step and the lower step.
2. The construction method for passing through the urban main road by underground excavation of the water-rich sandy gravel stratum transition line section is characterized in that a section transition area is arranged during conversion of each construction method, the width of an initial lining of the section transition area is 2000-4000mm, grids are arranged at the section transition area and the section conversion position, the grid processing of the section transition area is performed according to the space of 360-380mm, the grids are formed by welding after cold bending forming, and the sections have two forms consisting of 3 and 4 main ribs; the diameter of the main rib is 25-30mm, and the height of the section is 150-160 mm; the main reinforcement is connected with a contact steel bar, the diameter of the contact steel bar is 15-20mm, and the contact steel bar is welded at the end part of the main reinforcement by a connecting plate; trial assembly is carried out after the grid is machined, and all unit elements of the grid are connected through mining bolts.
3. The construction method for the transitional segment of the water-rich sandy gravel stratum to be excavated and passed through the urban trunk road according to the claims 1-2 is characterized in that the upper part of a grid at the section transition is processed by I25b I-steel, and the top width of a primary lining at the section transition is expanded outwards appropriately according to the height of the section steel; the grid is divided into 25 units for processing, and steel plates with the width of 25mm and the thickness of 10mm are welded on the outer sides of the middle plate and the bottom plate of the grid; the grid of section conversion department is the shaped steel material, and the grid of section transition zone perpendicular to section axle center is encrypted and is arranged, adopts welded connection with the grid of section conversion department.
4. The construction method for the crossing of the urban arterial road by the covered excavation of the cross line section of the water-rich sandy gravel stratum as claimed in claim 3, wherein the precipitation construction comprises the following specific steps: checking the position of the dewatering well, excavating after confirming that no fault exists, and burying a wall protecting pipe; after the wall protecting pipe is buried, a percussion drill is used for punching and drilling holes, and meanwhile, slurry is used for protecting the wall, so that the height of slurry in the holes is kept, the holes are prevented from collapsing, and the holes are formed when the drilling depth reaches a designed value; vertically putting a reinforced concrete well pipe after hole forming; filling gravels into the precipitation well with the reinforced concrete well pipe fixed, and forming a filtering layer for precipitation; cleaning the dewatering well, and filling clay to seal the well.
5. the construction method for underground excavation and crossing of the urban main road for the cross section of the water-rich sandy gravel stratum as claimed in claims 1 to 4, wherein the bore diameter of the bore hole is 610-620mm, the inner diameter of the reinforced concrete well pipe is 300mm, the outer diameter of the reinforced concrete well pipe is 400mm, and the particle size of the gravel is 5-6 mm.
6. The construction method for crossing city arterial road by covered excavation of water-rich sandy gravel stratum transition line segment according to claim 5, characterized in that the annular spacing of the arched pipe sheds is 0.5-0.6 m, and the arched variable-section tunnel is surrounded by the pipe sheds; the length of a single section of the arched pipe shed is 4m or 2m, and the pipe sheds are overlapped in a staggered mode through staggered use.
7. The construction method for the crossing of the urban arterial road by the underground excavation of the water-rich sandy gravel stratum transition line segment according to the claims 1 to 6, wherein the determination of the grid form is specifically as follows: establishing a grid model design by using BIM, optimizing grid formats according to different section sizes and excavation modes, and performing simulation comparative analysis to form an effective model; and a finite element simulation construction process is adopted to predict the surface subsidence, and a pertinence measure for reducing subsidence is formulated by combining a prediction conclusion, so that a grid form is determined.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910871776.3A CN110552704B (en) | 2019-09-16 | 2019-09-16 | Construction method for underground excavation of water-rich sandy gravel stratum crossover section through urban main road |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910871776.3A CN110552704B (en) | 2019-09-16 | 2019-09-16 | Construction method for underground excavation of water-rich sandy gravel stratum crossover section through urban main road |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN110552704A true CN110552704A (en) | 2019-12-10 |
| CN110552704B CN110552704B (en) | 2020-06-30 |
Family
ID=68740353
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201910871776.3A Active CN110552704B (en) | 2019-09-16 | 2019-09-16 | Construction method for underground excavation of water-rich sandy gravel stratum crossover section through urban main road |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN110552704B (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112576264A (en) * | 2020-12-16 | 2021-03-30 | 北京市政建设集团有限责任公司 | Tunnel excavation method for penetrating through sand bed section |
| CN114876526A (en) * | 2022-05-27 | 2022-08-09 | 中铁十一局集团有限公司 | Temporary side wall protection construction method by double side wall pit guiding method |
| CN115961513A (en) * | 2022-11-22 | 2023-04-14 | 中铁二院工程集团有限责任公司 | Method for carrying out quadruple interchange fluffing on railway by using tunnel engineering |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103643973A (en) * | 2013-12-03 | 2014-03-19 | 中铁十三局集团有限公司 | CRD construction method tunnel waterproof construction method |
| CN104612698A (en) * | 2015-01-24 | 2015-05-13 | 杭州天恒投资建设管理有限公司 | Method for constructing upper step middle partition wall of shallow-buried excavation tunnel |
| CN106050266A (en) * | 2016-07-22 | 2016-10-26 | 中铁建大桥工程局集团第五工程有限公司 | Construction method for undermining connected channel between shield sections in water-rich sand cobble stratum tunnel |
| JP6043454B1 (en) * | 2016-06-27 | 2016-12-14 | 鹿島建設株式会社 | Construction method of underground structure and underground structure |
| CN108316931A (en) * | 2018-03-05 | 2018-07-24 | 北京市政建设集团有限责任公司 | A kind of branch-cut bridge section tunnel CRD method construction methods |
| CN108843346A (en) * | 2018-07-18 | 2018-11-20 | 中铁十二局集团第二工程有限公司 | Lining construction method of the large section shallow-depth-excavation tunnel in water-rich sand layer |
| CN110219656A (en) * | 2019-07-15 | 2019-09-10 | 福建工程学院 | A kind of advance reinforcement construction method of plenty water weak surrounding rock tunneling |
-
2019
- 2019-09-16 CN CN201910871776.3A patent/CN110552704B/en active Active
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103643973A (en) * | 2013-12-03 | 2014-03-19 | 中铁十三局集团有限公司 | CRD construction method tunnel waterproof construction method |
| CN104612698A (en) * | 2015-01-24 | 2015-05-13 | 杭州天恒投资建设管理有限公司 | Method for constructing upper step middle partition wall of shallow-buried excavation tunnel |
| JP6043454B1 (en) * | 2016-06-27 | 2016-12-14 | 鹿島建設株式会社 | Construction method of underground structure and underground structure |
| CN106050266A (en) * | 2016-07-22 | 2016-10-26 | 中铁建大桥工程局集团第五工程有限公司 | Construction method for undermining connected channel between shield sections in water-rich sand cobble stratum tunnel |
| CN108316931A (en) * | 2018-03-05 | 2018-07-24 | 北京市政建设集团有限责任公司 | A kind of branch-cut bridge section tunnel CRD method construction methods |
| CN108843346A (en) * | 2018-07-18 | 2018-11-20 | 中铁十二局集团第二工程有限公司 | Lining construction method of the large section shallow-depth-excavation tunnel in water-rich sand layer |
| CN110219656A (en) * | 2019-07-15 | 2019-09-10 | 福建工程学院 | A kind of advance reinforcement construction method of plenty water weak surrounding rock tunneling |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112576264A (en) * | 2020-12-16 | 2021-03-30 | 北京市政建设集团有限责任公司 | Tunnel excavation method for penetrating through sand bed section |
| CN114876526A (en) * | 2022-05-27 | 2022-08-09 | 中铁十一局集团有限公司 | Temporary side wall protection construction method by double side wall pit guiding method |
| CN115961513A (en) * | 2022-11-22 | 2023-04-14 | 中铁二院工程集团有限责任公司 | Method for carrying out quadruple interchange fluffing on railway by using tunnel engineering |
Also Published As
| Publication number | Publication date |
|---|---|
| CN110552704B (en) | 2020-06-30 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN110552704B (en) | Construction method for underground excavation of water-rich sandy gravel stratum crossover section through urban main road | |
| CN210013697U (en) | Construction structure of near-penetrating building of underground excavation section of subway station entrance and exit | |
| CN112253133B (en) | Safe and efficient construction method for large-section underground excavation tunnel with upper soft and lower hard rock mass | |
| CN109026064B (en) | Construction method for large-span multi-arch tunnel with semi-bright and semi-dark | |
| CN109184700B (en) | Construction method for clamping rock in soft surrounding rock small-clear-distance tunnel stability | |
| CN110700841B (en) | Double-side-wall guide pit type excavation method for tunnel excavation | |
| CN102094649A (en) | Method for constructing underground space by shield-shallow buried covered excavation composite method | |
| CN110306593A (en) | A kind of station construction method | |
| CN110566223B (en) | Deep-buried PBA subway station section design method | |
| CN110230495B (en) | Core soil excavation method for double-side-wall pilot tunnel construction of subway station | |
| CN111472790A (en) | Construction structure and construction method for controlling settlement of shallow-buried underground excavation large-section tunnel | |
| CN110761811A (en) | Layered soft rock tunnel asymmetric supporting structure and construction method | |
| CN109538219B (en) | In-situ expansion super-large section and partial excavation method of broken hard rock tunnel | |
| KR20180118009A (en) | Duplex tunnel construction method | |
| KR20190079588A (en) | Construction Method of Duplex Tunnel | |
| CN110985042A (en) | Urban comprehensive pipe gallery and underground shallow-buried underground tunnel combined supporting system and process | |
| CN112922646B (en) | Building method of underground excavation station excavated by large-section single-span support through superposed arch-wall integrated type | |
| CN112727484B (en) | Shield-pipe-jacking up-down parallel overlapping tunnel structure and construction method thereof | |
| CN110735641B (en) | Construction method of transfer passage of underpass pipeline | |
| CN110761795B (en) | Construction method of shallow tunnel in loess gully | |
| CN211342952U (en) | Asymmetric supporting construction in stratiform soft rock tunnel | |
| CN210597377U (en) | Utility tunnel constructs structure with building together of subway station | |
| CN110656942B (en) | Tunnel surrounding rock deformation control method applied to granite altered zone under seepage condition | |
| CN112302662B (en) | Construction method of artificial backfill shallow-buried tunnel passing through highway | |
| CN211648187U (en) | Underground passage small-section multi-pipe parallel jacking system |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |