JP2000352296A - Method o constructing passage just under underground structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To shorten a term of works by constructing a pipe roof by inserting a plurality of pipes into a cured part obtained by injecting chemicals to the foundation crushed stone or natural ground on a lower side of an underground structure, and excavating the inside of the roof to construct a passage. SOLUTION: Underground passages connecting to a passage is constructed at both sides of natural ground, chemicals are injected to the natural ground and the foundation crushed stone between the underground passages and cured to form a cured part 25 at a lower side of a subway 10 and the like. Then a plurality of top pipes 15 are laterally aligned one line and inserted in a top end of the passage, and steel sheer piles 22 are laterally aligned one line and inserted in a bottom of the passage. Ten a plurality of side pipes 16 are longitudinally aligned one line and inserted form the top pipes 15 toward the lower side to execute the back filling grouting on the cured part 25 by utilizing the pipes 15, 16. Core members 17 are inserted into the top pipes 15, and inside filling concrete 18 is filled in the pipes 15, 16 to construct a pipe roof 11. Then the cured part 25 surrounded by the roof 11 and the steel sheer piles 2 is excavated, and the passage is constructed by forming a primary lining 12 and a secondary lining 13. Thereby a term of works can be shortened.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for forming a passage directly under an underground structure.

[0002]

2. Description of the Related Art For example, when a passage intersecting with a subway is formed immediately below a subway, an underpeening method has conventionally been generally used. This underpeening method is to excavate only the upper part of the planned passage area immediately below the subway first, and to use the excavated space to directly support the subway, for example, use a plurality of H-beams etc. Piles are continuously driven by a BH (boring hill) method or the like in order to form the earth retaining walls located on both sides of the passage while being arranged horizontally. Then, a passage is formed by excavating the inside of the retaining wall.

[0003]

However, when a passage is formed directly under the subway by the underpeening method as in the prior art, a portion of the passage is excavated, a lower girder is disposed each time, and a soil retaining wall is used. Since the piles have to be driven in, the construction period is lengthened, and work such as placement of the support girder and pile driving for the retaining wall is performed directly under the subway, so that the workability is deteriorated. Such a problem is not limited to a subway, and occurs similarly when a passage is formed immediately below an underground structure.

[0004] An object of the present invention is to solve such a problem, and it is possible to shorten the working time and reduce the work directly under the underground structure. An object of the present invention is to provide a method for forming a passage.

[0005]

SUMMARY OF THE INVENTION The present invention is a method for forming a passage immediately below an underground structure, and is configured as follows to solve the above-mentioned technical problem. That is, the present invention forms a hardened portion by injecting a chemical solution into the foundation crushed stone or ground under the underground structure, forms a pipe roof by inserting a plurality of pipes into the hardened portion, the pipe roof, The passage is formed by excavating the inside of the roof.

[0006] A core material can be inserted into the pipe at least at the top end of the pipe roof, concrete can be filled into the pipe, and a sheet pile can be inserted into the bottom of the passage. The underground structure may be a subway.

(Action) According to the method of forming a passage directly under an underground structure according to the present invention, a hardened portion is formed by injecting a chemical solution into a base crushed stone or ground under the underground structure, and the hardened portion is formed. By inserting a plurality of pipes into the pipe fool, the pipe roof can support the underground structure through the hardened part, so that the entire inside of the pipe roof can be excavated, The man-hour can be reduced, and the work directly under the underground structure can be reduced as compared with the conventional underpeening method.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a method for forming a passage immediately below an underground structure according to the present invention will be described below in detail with reference to the drawings.

FIG. 1 is a sectional view showing a passage 1 to which a method for forming a passage immediately below an underground structure according to the present invention is applied. The passage 1 is disposed immediately below the underground structure, for example, the subway 10 so as to intersect with the subway 10. Passage 1
, A gate-shaped pipe rule 11, a sheet pile 22 disposed below the pipe roof 11, and primary linings 12 and 2, which are cast inside the pipe roof 11 and the sheet pile 22. Next lining 13 and pipe roof 11
Crushed stone 26 (Fig. 2) between the subway 10 and the subway 10
There is provided a curing unit 25 which is cured by injecting a chemical.

The pipe roof 11 is composed of a plurality of top pipes 15 buried in a horizontal line directly below the subway 10 and a plurality of side pipes 16 arranged in a vertical line below both ends of the top pipe 15. Is formed. As shown in FIG. 2, a core member 17 such as an H-section steel is inserted into the top pipe 15, and the top pipe 15 is further filled with a filling concrete 18. Thus, the second moment of area of the top pipe 15 is increased, and the amount of bending of the top pipe 15 is reduced. The side pipe 16 is filled with a filling concrete 18.

Next, a method of constructing the passage 1 will be described. Here, first, as shown in FIG. 3, a space portion connected to the passage 1, for example, underground passages 20 and 21 is provided on both sides of the ground 14 where the passage 1 is to be constructed. Underpass 20, 2
1 keeps subway 10 off. Next, a chemical solution is injected into the ground 14 and the foundation crushed stone 26 between the underpasses 20 and 21, and the current ground is improved (reinforcement work).

As a result, as shown in FIG.
The hardened part 25 is formed below the ground, and the inflow of groundwater can be prevented, and the collapse angle of the ground can be set to about 67.5 °. Therefore, the ground reaction force coefficient is expected to be 5 to 6 times that of the normal ground. It is possible to stabilize the hardened portion 25 during excavation.

Next, a plurality of top pipes 15 are inserted in a row at the top end of the passage 1, and a plurality of steel sheet piles 22 are inserted in a row at the bottom of the passage 1 as a sheet pile. Here, there is another underground structure (not shown) on the bottom side of the passage 1 and there is not enough working space for inserting the pipe, so the steel sheet pile 22 that can be inserted is inserted. Pipes can be inserted if there is enough working space.

Subsequently, as shown in FIG. 5, a plurality of side pipes 16 extend downward from the top pipes 15 at both ends.
Is inserted vertically in a line. Next, back filling is performed into the hardened portion 25 using the top pipe 15 and the side pipe 16.
As a result, the periphery of the top pipe 15 and the side pipes 16 is filled with the reinforcing material, and the gap is filled. Next, the core member 17 is inserted into the top pipe 15, and
5 and the side pipe 16 are filled with filling concrete 18. Thereby, the portal-type pipe roof 11 is formed.

Next, as shown in FIG.
The hardened portion 25 surrounded by 1 and the steel sheet pile 22 is excavated sequentially from the end. In this case, since the entire cross section can be excavated, the excavation time can be reduced. Also, in this case,
Since the collapse angle of the hardened portion 25 is about 67.5 ° due to the injection of the chemical, it is possible to prevent the hardened portion 25 from being collapsed during excavation. As the excavation proceeds, the pipe roof 11 is sequentially exposed from the end, and this is appropriately supported by the shoring 23.

After the hardened portion 25 surrounded by the pipe roof 11 and the steel sheet pile 22 is excavated in this way, concrete is poured on the inner peripheral surfaces of the pipe roof 11 and the steel sheet pile 22 as shown in FIG. Then, the primary lining 12 and the secondary lining 1
Form 3 Thereby, the construction of the passage 1 is completed.

If the load on the ground 14 above the subway 10 is large and the strength of the pipe roof 11 cannot withstand it, the ground 14 above the subway 10 is removed and this part is replaced with EPS (Styrofoam). ) Can be used to reduce the weight.

As described above, according to the method for forming a passage directly under a subway according to the present invention, the base crushed stone 2 under the subway 10 is provided.
After a chemical solution is injected into the ground 6 or the ground 14 to form a hardened portion 25 and the pipe fool 11 is formed in the hardened portion 25,
Since the inside of the pipe roof 11 is excavated, it is possible to excavate the entire cross section, and the working time can be reduced as compared with the conventional underpeening method, and the subway 10 can be excavated.
It is possible to reduce the work directly under the subway 1
The effect on 0 can be minimized.

In the above embodiment, the subway 10
Although the case where the passage 1 is formed immediately below is described, the present invention is not limited to this, and can be applied to the case where the passage 1 is formed immediately below various underground structures.

[0020]

As described above, according to the present invention,
Since the inside of the pipe roof can be excavated by full-section excavation, the work time can be reduced as compared with the conventional underpeening method, and the work directly under the underground structure can be reduced. The effect on objects can be minimized.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a passage to which a method for forming a passage immediately below an underground structure according to the present invention is applied.

FIG. 2 is a sectional view showing a top pipe of a pipe roof according to the present invention.

FIG. 3 is a diagram illustrating a method of forming a passage immediately below an underground structure according to the present invention.

FIG. 4 is a diagram illustrating a method for forming a passage immediately below an underground structure according to the present invention.

FIG. 5 is a diagram illustrating a method of forming a passage immediately below an underground structure according to the present invention.

FIG. 6 is a diagram illustrating a method of forming a passage immediately below an underground structure according to the present invention.

[Explanation of symbols]

 Reference Signs List 1 passage 10 subway (underground structure) 11 pipe roof 14 ground 15 top pipe (pipe at top end) 17 core member 18 filled concrete 22 steel sheet pile (sheet pile) 25 hardened section 26 basic crushed stone

Claims (5)

[Claims] 1. A pipe roof is formed by injecting a chemical solution into a foundation crushed stone or ground under an underground structure to form a hardened portion, and inserting a plurality of pipes into the hardened portion, wherein the pipe roof is formed. A method for forming a passage immediately below an underground structure, wherein the passage is formed by excavating the inside of the building. 2. A core material is inserted into at least a top end portion of the pipe roof.
3. The method for forming a passage immediately below an underground structure according to item 1. 3. The method according to claim 1, wherein the pipe is filled with concrete. 4. The method according to claim 1, wherein a sheet pile is inserted into a bottom portion of the passage. 5. The method according to claim 1, wherein the underground structure is a subway.