JPH10152852A - Method of building underground structure and structural member used therein - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method of building an underground structure, which is safe, which can simply and precisely build the structure, and which can reduce the building cost and shorten the construction period thereof, and to provide structure members used therefor. SOLUTION: A method of building an underground structure comprises the steps of driving sheathing wall members 20 into the ground, excavating the ground surrounded by sheathing wall members 20 through underwater-excavation up to a predetermined depth D, after floating an assembly of a ring-like working face fixture 21 having no opening in the lower part thereof, and a ring-like member 10 set up on the fixture 21 on the water surface inside of the sheathing members 10, arranging a float scaffold 22 in the ring-like members 10, laying ring-like members 10, 10... in a next lot, so as to adjust the buoyancy, and joining the ring-like members 10 together while increasing the depth thereof, after sinking the ring-like members 10 up to a desired depth, inserting a tremie pipe 23 into the ring-like members 10 through a vertical shaft, thereafter placing concrete in the ring-like members 10, and underwater placing a hardener between the ring-like members 10 and the sheathing wall members 20 so as to build an underground structure.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for constructing an underground structure and a structural member used for the method.

[0002]

2. Description of the Related Art Conventionally, underground structures for use in the air, such as foundations for supporting buildings and shafts, have been constructed mainly by a deep foundation method or an underground wall method. Therefore, these construction methods will be briefly described with reference to FIGS. FIG.
Fig. 8 shows the deep foundation method, and Fig. 8 shows the underground continuous wall method.

First, a construction procedure by the deep foundation method will be described with reference to FIG. A worker enters the mine and excavates the pit wall manually using a scoop or the like. At this time, excavation is performed while attaching a formwork to prevent collapse of the pit wall. Further, if necessary, a chemical solution or the like is injected. Also,
In order to prevent oxygen deficiency in the pit, air is blown by a blower 100.

[0004] The excavated earth and sand is carried out of the mine by winding a bucket 102 attached to a tower 101 assembled on the mine with a winch 103. Also, the spring water from the excavation is drained out of the pit by the pump 104. Then, after reaching a desired depth, a reinforcing bar is erected in the pit and concrete is poured with a tremy tube or the like. Earth retaining material is removed or buried depending on the condition of the ground and the purpose. In this way, an underground structure is constructed.

This deep foundation method is excellent in that it allows visual confirmation of the excavated surface, that it can be constructed even in places where large construction machines such as mountainous areas and sloping land are difficult to carry in, and that noise and vibration are small. I have.

Next, a construction procedure by the underground continuous wall method will be described with reference to FIG. First, excavation for the preceding panel is performed using the excavator 110. At this time, in order to prevent the collapse of the surrounding ground, the excavation trench is filled with a stable liquid (FIG. 8A). After the excavation is completed, the reinforced cage 111a incorporating the joint between the walls is suspended by a crane. Reinforcing cage 111a
After the completion of the installation, the partition plate 112 and the joint protective material 113
Is inserted (FIG. 8B). Subsequently, concrete is sequentially poured from the groove bottom using the tremy tube 114 into the portion partitioned by the partition plate 112 (FIG. 8C). Thus, the preceding panel is completed.

Subsequently, the excavator 110 excavates the following panel (FIG. 8 (d)). After the excavation is completed, the joint is cleaned using a joint cleaning machine. Like the preceding panel,
The rebar basket 111b for the succeeding panel is erected between the preceding panels (FIG. 8E). Then, concrete is sequentially poured from the groove bottom using the tremy tube 114 (FIG. 8).
(F)). In this way, an underground structure having a continuous wall is constructed (FIG. 8 (g)).

The underground wall construction method is excellent in that it has little effect on the surrounding ground, has a wide application range from soft ground to rock, and has low noise and vibration and can prevent construction pollution. In recent years, along with the improvement of construction technology, not only as a temporary retaining water barrier, but also a permanent underground outer wall that bears long-term earth pressure water pressure, or a seismic wall that bears horizontal force during an earthquake , Is used as a foundation pile.

Recently, various construction methods of underground structures have been developed. One of them, the press-fitting open caisson method, will be described with reference to FIG. FIG. 9 is an explanatory diagram of the press-fit type open caisson method. This method first installs a ground anchor 120 in the ground, builds a caisson 121 on the ground, and excavates the inside underwater,
By taking a reaction force to the steel wire of the anchor 120, the supporting plate 122,
It is pressed into the ground by the jack 124 via the loading girder 123. After that, when the caisson 121 is sunk to a desired depth, bottom slab concrete is cast to construct an underground structure.

[0010] This construction method is safe because no workers enter the mine. In addition, there is no need to perform ground improvement, there is no need for a plant for stabilizing liquid, and it is economical, and there is no problem of raising or lowering nearby neighboring buildings.

[0011]

However, as described above, the deep foundation method is based on manual work, and requires a worker to enter the mine to perform work. Poisonous gas generation and stagnation may occur. In addition, regarding excavation, it is necessary to respond to the collapse of the pit wall by injecting chemicals etc. according to the ground conditions while constantly conducting ground surveys and comparing and examining excavated earth and sand. It can also have an effect. That is, the deep foundation method has such various problems.

On the other hand, in the underground continuous wall method, it is necessary to improve the ground of the bottom slab and prevent the continuous slab from being collapsed in order to prevent collapse of the bottom slab. In addition, excavation is performed by filling the excavation trench with a stable liquid to prevent collapse of the hole wall. Therefore, there is a problem that since a plant for a stabilizing solution is required, a large site and construction cost are required. In addition, there is a problem that the time required for installation / removal of the plant is long, and the construction period is prolonged accordingly.

Further, in the press-fitting open caisson method, since the skeleton construction work and the excavation work are performed alternately, it is necessary to repeat the curing of the skeleton and the detachment work of the supporting plate, the loading girder, and the jack. It costs. Furthermore, when press-fitting the caisson, several jacks are inserted into the loading girder and the caisson is press-fitted.If the force applied to each jack is not precisely adjusted, the vertical accuracy cannot be ensured. There is a problem that work is troublesome. In addition, even if this adjustment is performed accurately, there is a possibility that a press-fit may be performed at an angle due to a change in the stratum.

Accordingly, the present invention has been made to solve the above-mentioned problems, and it is possible to construct an underground structure which is safe, can be easily and accurately constructed, and can reduce the construction cost and the construction period. An object of the present invention is to provide a construction method and a structural member used for the method.

[0015]

In order to solve the above-mentioned problems, according to the first aspect of the present invention, in a method of constructing an underground structure, a soil retaining material is driven into the ground, and the ground retaining material is used. A first step of excavating the partitioned interior to a desired depth by underwater excavation, and forming an annular hollow structural member on an annular blade fitting having no opening at the bottom, the water surface inside the earth retaining material; After floating, the second step of installing a float scaffold inside the annular hollow structural member and adjusting the buoyancy by installing an annular hollow structural member of the next lot on the annular hollow structural member floating on the water surface And a third step of joining the annular hollow structural members to each other using the float scaffold, and sequentially decreasing the depth by repeating the third step to lay down an underground structure having a desired depth. And four steps. .

At the time of excavation, since there is no need for an operator to enter the mine, the construction can be performed safely. Further, since there is no need to change the water in the pit, it is not necessary to perform ground improvement. Therefore, the configuration of the earth retaining material can be simplified, and since no formwork is involved, labor saving and shortening of the construction period are possible, and the construction cost can be reduced. In addition, the excavation work and the assembling work of the structural members are independent, and the assembling work and the submerging work of the structure proceed simultaneously, so that the construction period can be shortened. Here, the shape of the annular hollow structural member includes shapes such as a circular shape, an elliptical shape, an oval shape, and a rectangular shape. That is, since the inner wall surface of the annular hollow structural member only needs to form a closed curved surface, the annular hollow structural member can be manufactured in various shapes.

Further, since the sunk depth can be changed by adjusting the buoyancy of the structural member for underwater construction, the joining operation performed on the float scaffold can be easily performed. In addition, since there is no need to apply external force to the structural members during the laying operation as in the case of the press-fit type open caisson method, it is possible to perform the construction without using construction equipment such as jacks. In addition, when the structural member is installed in the ground, the buoyancy is used and the buoyancy is gradually buried while maintaining the gravity balance. Therefore, even if the excavation hole is slightly bent, the structural member can be accurately sunk in the vertical direction. .

According to a second aspect of the present invention, in order to solve the above problem, in the construction method of the underground structure, after the fourth step of the underground structure construction method according to the first aspect, Casting concrete into the annular hollow structural member,
Thereafter, underwater concrete is poured into the bottom of the pit, and a hardening material is poured underwater between the annular hollow structural member and the earth retaining material to construct an underground structure.

According to a third aspect of the present invention, in order to solve the above problems, in the construction method of an underground structure according to the second aspect, a hardening material is provided between the annular hollow structural member and the earth retaining material. After being cast underwater, the earth retaining material is removed.

When the earth retaining material is removed, the earth retaining material is pulled out before the hardened material is hardened, so that the hardened material is filled with no gap between the hardened material and the ground. Further, since the hardening material is removed and then hardened, there is no influence on the surrounding ground, and the surrounding ground and the adjacent structures are not settled or depressed.

According to a fourth aspect of the present invention, there is provided a structural member used in the method of constructing an underground structure according to the first aspect, wherein the annular hollow structural member is constructed. In addition, an opening is formed in the main girder portion so as to coincide with the vertical direction.

Since the main girder has an opening which is vertically aligned with the main girder, the tremee pipe can be hung into the structural member, and concrete can be poured sequentially from the bottom, so that the skeleton can be easily formed. Since concrete can be constructed and construction curing is not required, the construction period can be shortened. Also, even if concrete is poured directly from the opening formed in the uppermost structural member without using a tremy tube, concrete flows through the opening of each structural member, and concrete enters the structural member. Since it is filled, skeleton concrete can be constructed.

[0023]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, a structural member of an underground structure and a construction method according to the present invention will be described in detail with reference to the drawings, taking concrete embodiments. 1 to 3 show an embodiment of a structural member of an underground structure according to the present invention.
This will be described with reference to FIG. FIG. 1 is a perspective view of a structural member, FIG.
FIG. 3 is a sectional view of the structural member.

As shown in FIG. 1, FIG. 2, and FIG. 3, the structural member 1 includes six inner and outer portions, upper and lower portions, and end portions, and the material of each wall is a steel plate. It is an arc-shaped member manufactured by welding. The inside of the structural member partitioned by each steel plate is hollow. And
In the center of the steel plates 2 on the upper and lower surfaces, a vertical through hole 2a,..., On both sides thereof, vertical connection holes 2b,. Horizontal connection holes 3 on both sides
are formed respectively. These joint holes 2
b and 3b are for joining each member when constructing a structural member, and the through holes 2a and 3a are
It serves as an air hole and a concrete flow path when placing concrete after construction. As shown in FIG. 6, the vertical through holes 2a are formed at positions where the structural members 1, 1,... Are staggered in the vertical direction so as to be linear in the vertical direction. Therefore, when constructing the structural member, the tremee pipe can be inserted into the structural member when concrete is poured into the structural member. In addition, steel plates 4 on the inner and outer surfaces
A cutout 4c is formed in each of the joints a and 4b so that each member can be connected in the vertical and horizontal directions.

When four arc-shaped structural members 1 are joined in the horizontal direction, four annular members 10 as shown in FIG.
Is completed. Further, by joining this annular member 10 in the vertical direction, a structural member of an underground structure having an arbitrary length can be manufactured. Each structural member 1,1,
Are joined by bolt joining, welding, or the like.
Further, after joining, the notch 4c may be closed by welding a steel plate to the outside, or filling a filler.

As described above, the structural member 1 of the present invention
Since the inside is hollow, it is lightweight, and because it is assembled at the site, it is easy to transport to the construction site,
There is no need to take up a large storage area on site. Furthermore, a large-sized heavy machine is not required at the time of installation, and can be installed with a general-purpose heavy machine. Therefore, if an underground structure is constructed by using the structural member 1 of the present invention, the construction cost can be reduced. Also, the main girder part has an opening that matches the vertical direction, so that the tremee pipe can be hung into the structural member, and concrete can be poured sequentially from the bottom, making it easy to build concrete Can be constructed,
Moreover, since no construction curing is required, the construction period can be shortened.

Next, a method of constructing an underground structure using the annular member 10 will be described with reference to FIG. First, the earth retaining material 20 such as a steel sheet pile is installed underground deeper than the depth D of the underground structure to be constructed (FIG. 5).
(A)). Next, the inside partitioned by the earth retaining material 20 is excavated to a desired depth D by underwater excavation using an excavator (FIG. 5B). Since the earth retaining material 20 prevents the collapse of the pit wall, underwater excavation can be performed without using a stable liquid. Further, as will be described later, since the assembling of the annular member is performed by underwater construction, there is no need to perform bottom improvement, and since stress due to water pressure does not occur in the earth retaining material,
Since the configuration is simple, it is economical and leads to a reduction in construction costs.

Next, the annular member 10 previously assembled on the annular blade fitting 21 on the ground is lifted by a crane and floated on the water surface in the pit. This blade fitting 21 is
The bottom has a blade shape, and a hole communicating with the vertical through hole 2a of the annular member 10 is formed at the top (not shown). Joining of the blade base 21 and the annular member 10 is also performed by bolt joining, welding, or the like.

Then, the float scaffold 22 is set inside the annular member 10 (FIG. 5C). Subsequently, the annular member 10 of the next lot is floating in the water in the mine.
Assemble on When assembling the structural member 10 of the next lot, the annular members 10 are joined in the vertical direction using the float scaffold 22. The joining at this time is also performed by bolt joining, welding, or the like. When the annular members 10 are joined to each other, the assembled annular member 10 sinks below the water surface to lower the depth due to the weight of the annular member 10 (FIG. 5D). At this time, weight is added as necessary to balance the weight (adjustment of buoyancy) to facilitate the joining work on the float scaffold. After that, the setting process is repeatedly performed until the lower end of the blade fitting 21 is fixed at a desired depth D. Here, it is also possible to use water as the weight, and the water used as the weight is replaced by concrete poured into the annular member and drained.

In the setting step, it is possible to assemble one stage at a time or at many stages. Further, when sequentially constructing the annular member 10 in the vertical direction, as shown in FIG.
Strength can be increased by the attachment effect.

The annular member 10 having a hollow structure as described above
By using the buoyancy, the buoyancy can be used in the construction process, so that the construction can be performed by a general-purpose heavy machine without requiring a large-sized heavy machine. Further, since the burial is sequentially buried while maintaining the gravity balance, the structural member can be accurately laid down in the vertical direction even if the digging hole is slightly bent.

After fixing to the desired depth D, the float scaffold 22 is removed and the sediment at the bottom of the pit is removed. And
Since the vertical through holes 2a formed on the upper and lower surfaces of the annular member 10 are open in the vertical direction, the opening (the vertical through hole 2a)
The tremy tube 23 is suspended by using a crane, and concrete is sequentially poured into the annular member 10 from the bottom (FIG. 5E). When the casting of the concrete inside the annular member 10 is completed, the bottom slab concrete is poured underwater on the bottom of the pit. Thereafter, the filling between the annular member 10 and the earth retaining material 20 is performed by casting a hardened material obtained by solidifying excavated earth and sand underwater.

Finally, the water in the mine is discharged by a pump,
Remove the earth retaining material before the filling material hardens. In some cases, the earth retaining material may be buried and killed. Through the above operations, a shaft, which is an underground structure, is constructed (FIG. 5 (f)).

When removing the earth retaining material, the earth retaining material is pulled out before the hardened material is hardened, so that the hardened material is filled without gaps between the hardened material and the ground. Further, since the hardening material is removed and then hardened, there is no influence on the surrounding ground, and the surrounding ground and the adjacent structures are not settled or depressed.

As described above, according to the method of constructing an underground structure according to the present invention, there is no need for an operator to enter a pit during excavation, so that construction can be performed safely. Further, since there is no need to change the water in the pit, it is not necessary to perform ground improvement. Therefore, the configuration of the earth retaining material can be simplified,
Further, since no mold work is involved, labor saving and shortening of the construction period are possible, and the construction cost can be reduced. In addition, the excavation work and the assembling work of the structural members are independent, and the assembling work and the submerging work of the structure proceed simultaneously, so that the construction period can be shortened.

Furthermore, the depth can be changed by adjusting the buoyancy of the structural member for underwater construction, so that the joining operation performed on the float scaffold can be easily performed. In addition, since there is no need to apply external force to the structural members during the laying operation as in the case of the press-fit type open caisson method, it is possible to perform the construction without using construction equipment such as jacks. Also, when installing structural members underground,
Since the buoyancy is used to sequentially bury the cavities while maintaining the gravity balance, the structural members can be accurately sunk in the vertical direction even if the excavation holes are slightly bent.

Although the embodiments of the present invention have been described above, the present invention is not limited to the above embodiments, and various applications are possible. For example, in the present embodiment, the outer surface of the structural member is flat, but if a protrusion is provided on this outer surface,
It is possible to construct an underground structure that is strong against pushing and pulling.

[0038]

According to the method of constructing an underground structure of the present invention, a first step of driving a soil retaining material into the ground and excavating the interior partitioned by the soil retaining material to a desired depth by underwater excavation. After floating an annular hollow structural member on an annular blade base having no opening at the bottom on the water surface inside the earth retaining material, a float scaffold is installed inside the annular hollow structural member. In the second step, an annular hollow structural member of the next lot is installed on the annular hollow structural member floating on the water surface, buoyancy is adjusted, and the annular hollow structural members are joined to each other using the float scaffold. Since the underground structure is constructed by the third step and the fourth step of sequentially repeating the third step to lower the depth and laying the underground structure having the desired depth, the underground structure is constructed. Since there is no need for workers to enter the mine, It can be. Further, since there is no need to change the water in the pit, it is not necessary to perform ground improvement. Therefore, the configuration of the earth retaining material can be simplified,
Further, since no mold work is involved, labor saving and shortening of the construction period are possible, and the construction cost can be reduced. In addition, the excavation work and the assembling work of the structural members are independent, and the assembling work and the submerging work of the structure proceed simultaneously, so that the construction period can be shortened.

Further, the depth of submersion can be changed by adjusting the buoyancy of the structural member for underwater construction, so that the joining operation performed on the float scaffold can be easily performed. In addition, since there is no need to apply external force to the structural members during the laying operation as in the case of the press-fit type open caisson method, it is possible to perform the construction without using construction equipment such as jacks. In addition, when the structural member is installed in the ground, the buoyancy is used and the buoyancy is gradually buried while maintaining the gravity balance. Therefore, even if the excavation hole is slightly bent, the structural member can be accurately sunk in the vertical direction. .

Further, according to the structural member of the present invention, since the opening corresponding to the vertical direction is formed in the main girder portion after the construction, the trumy tube is suspended in the structural member after being submerged in the ground. Therefore, it is possible to easily apply the slab concrete, and the construction period can be shortened because no curing is required.

[Brief description of the drawings]

FIG. 1 is a perspective view of a structural member according to an embodiment of the present invention.

FIG. 2 is a sectional view taken along the line AA shown in FIG.

FIGS. 3A and 3B are cross-sectional views taken along arrows in each direction shown in FIG. 2; FIG.
(C) is a cross-sectional view taken along the line cc.

FIG. 4 is a sectional view of an annular member.

FIG. 5 is an explanatory diagram of a construction method according to an embodiment of the present invention.

FIG. 6 is an explanatory view illustrating a method of joining the annular member in a vertical direction.

FIG. 7 is an explanatory diagram of a construction method of a deep foundation method.

FIG. 8 is an explanatory view of a construction method of an underground wall construction method.

FIG. 9 is an explanatory diagram of a construction method of a press-fit type open caisson method.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Structural member 2 Upper and lower surface steel plate 2a Vertical through hole 2b Vertical connection hole 3 End surface steel plate 3a Horizontal through hole 3b Horizontal connection hole 4a, 4b Side steel plate 4c Notch 10 Ring member 20 Earth retaining material 21 Blade base 22 Float scaffold 23 Tremy tube

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Atsushi Ito Kanie-cho, Kaifu-gun, Aichi Prefecture, Kanie-cho, Nitta-shi, Shimo Market 19-1, Kato Construction Co., Ltd. No. Nippon Kokan Light Steel Co., Ltd.

Claims (4)

[Claims] 1. A construction method for constructing an underground structure, comprising: a first step of driving a soil retaining material into the ground and excavating an interior partitioned by the soil retaining material to a desired depth by underwater excavation; A second step of setting a float scaffold inside the annular hollow structural member after floating the annular hollow structural member on the annular blade base having no opening on the water surface inside the retaining material; A third step of installing the next lot of annular hollow structural members on the annular hollow structural members floating on the water surface, adjusting the buoyancy, and joining the annular hollow structural members to each other using the float scaffold; And a fourth step of successively repeating the third step to lower the depth and laying an underground structure having a desired depth. 2. A method for constructing an underground structure, wherein after the fourth step of the underground structure construction method according to claim 1, concrete is poured into the annular hollow structural member,
Then, an underwater concrete is poured into the bottom of the underground, and a hardening material is poured underwater between the annular hollow structural member and the earth retaining material to construct an underground structure. Construction method. 3. The method of constructing an underground structure according to claim 2, wherein the hardening material is poured underwater between the annular hollow structural member and the earth retaining material, and then the earth retaining material is removed. Construction method of underground structure which is the feature. 4. The structural member used in the method of constructing an underground structure according to claim 1, wherein when the annular hollow structural member is constructed, an opening corresponding to a vertical direction is formed in a main girder portion. A structural member characterized by being made.