JPH07139300A - How to build an underground structure - Google Patents

Abstract

(57) [Summary] [Purpose] Improvement of the method of constructing an underground retaining structure from the existing ground above by constructing a retaining wall from inside the tunnel excavated by the shield method. [Structure] The shield is started from the vertical shaft 1 to form tunnels 2 ₁ to 2 ₄ along the plane contour of the underground structure. The lower vertical soil retaining walls 3 _{1 to} 3 ₄ and the upper vertical water retaining walls 4 ₁ to 4 ₄ are constructed from inside the tunnel. Lowering the groundwater level inside the upper vertical water retaining walls 4 ₁ to 4 ₄ and constructing a horizontal earth retaining wall 5 between the tunnels 2 ₂ and 2 ₄ to construct a horizontal earth retaining wall 5 and a lower vertical earth retaining wall 3
_{1-3 4} a rigid joint, forming a Frame of Frame Structure. Excavating the frame to construct an underground structure. [Effect] One vertical shaft is enough. No need for structural columns or temporary columns. Easy and reliable construction of horizontal earth retaining wall and formation of frame.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of constructing an underground structure under an existing ground material such as a road, a railroad, a river or a structure.

[0002]

[Prior art and its problems] Under the tunnels excavated by the shield method, lower earth retaining walls are constructed from inside the tunnels respectively, and horizontal earth retaining walls are constructed between the tunnels on both sides. A method of excavating the inside surrounded by the earth retaining wall and the horizontal earth retaining wall and constructing an underground structure in this excavation portion is conventionally known, but in the conventional example of this method, it is necessary to start and reach the shield. Since each shaft has a vertical shaft, it is impossible to construct an underground structure if the site cannot be secured, and if the distance between the tunnels is long, a construction pillar will be installed from the ground level in the middle. It is necessary to support the mountain retaining wall, and when this structural pillar cannot be constructed from the ground, it is necessary to install a temporary pillar inside before constructing an underground structure. Lack of sex, Luo, since the construction in a state of generally a underground water, construction is difficult, there are problems like.

[0003]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a method for constructing an underground structure which does not have the above problems.

[0004]

The constructional feature of the method for constructing an underground structure according to the present invention is that a shield is started from a vertical shaft provided in a vacant lot near an existing aboveground structure, and an underground structure to be constructed below the existing aboveground structure. A tunnel is formed along the plane contour of the structure, a lower vertical earth retaining wall and an upper vertical water stop wall are constructed from the inside of the tunnel, and the groundwater level inside the upper vertical water stop wall is lowered to reach or exceed the groundwater level. Then, while constructing a horizontal earth retaining wall between the tunnels facing each other, and rigidly joining the horizontal earth retaining wall and the lower vertical earth retaining wall to form a frame structure of the ramen structure,
The point is to excavate the inside and construct an underground structure in this excavation part.

The main difference of the method of constructing an underground structure of the present invention from the conventional method is that a tunnel is formed along the plane contour of the underground structure to be constructed so that the tunnel for forming the tunnel is at one place. Even if a wide underground structure is constructed, the horizontal earth retaining wall can be constructed by rigidly joining the horizontal earth retaining wall and the lower vertical earth retaining wall to form a frame structure. We did not have to install supporting columns and temporary columns, provided an upper vertical water stop wall, lowered the groundwater level inside it, and constructed a horizontal earth retaining wall above the groundwater level and a horizontal earth retaining wall. By making a rigid connection between the wall and the lower vertical earth retaining wall, these operations can be performed easily and reliably.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The drawings are explanatory views in the case of constructing an underground structure under a road having a width W according to the present invention. In the present invention, first, a shield shaft 1 is shielded from a vertical shaft 1 provided in a vacant land on one side of the road. And a series of tunnels 2 ₁ , along the plane contour of the underground structure to be constructed under the road by the shield method.
2 ₂ , 2 ₃ , 2 ₄ are formed, but these tunnels 2 ₁ , 2
The cross-sectional shape of ₂ , 2 ₃ and 2 ₄ is preferably rectangular rather than circular.

[0007] After forming the end of the tunnel 2 _4, the shield so to ground connected to the tunnel 2 ₁ tip, vertical mine 1 may be one place.

Next, the tunnels 2 ₁ , 2 ₂ , 2 ₃ , 2 ₄
From the inside of the lower vertical earth retaining wall 3 ₁ , 3 ₂ , 3 ₃ , 3 ₄ and the upper vertical water blocking wall 4 ₁ , below and above them, respectively.
4 ₂ , 4 ₃ , 4 ₄ are constructed by an appropriate construction method, but it is desirable that the lower vertical earth retaining walls 3 ₁ , 3 ₂ , 3 ₃ , 3 ₄ have great rigidity.

[0009] Then, the upper vertical water-stop wall ₄ 1, 4,
Lowering the groundwater level inside 4 ₃ , 4 ₄ from H ₁ to H ₂ ,
A horizontal earth retaining wall 5 is constructed between the tunnels 2 ₂ and 2 ₄ facing each other in the lengthwise direction of the road at a groundwater level H ₂ or higher by a propulsion method, a horizontal boring method, or the like.

Reinforcing bars and concrete are placed inside the horizontal earth retaining wall 5, and PC steel material is also disposed if necessary, and both ends thereof are rigidly joined to the upper ends of the lower vertical earth retaining walls 3 ₂ , 3 _4. After constructing the frame structure 6 having a rigid frame structure, excavation is carried out while appropriately supporting the inside.

After excavating to the excavated bottom surface 7 of a predetermined depth, an underground structure is constructed in the excavation portion. At this time, it is preferable to use the frame 6 as a part of the skeleton of the underground structure.

[0012]

EFFECTS OF THE INVENTION Since the present invention is as described above, by forming it along the plane contour of the underground structure where the tunnel is to be constructed, only one vertical shaft for tunnel formation is required and the tunnel is horizontal. By constructing the frame structure of the ramen structure with the earth retaining wall and the lower vertical earth retaining wall, it is possible to construct a wide underground structure without installing structural columns and temporary columns, By lowering the groundwater level inward, there is an advantage that the construction of the horizontal earth retaining wall and the rigid joint construction of the horizontal earth retaining wall and the lower vertical earth retaining wall can be easily and surely performed.

[Brief description of drawings]

FIG. 1 is a plan view for explaining an embodiment of the present invention.

FIG. 2 is a sectional view taken along line XX of FIG.

FIG. 3 is an enlarged cross-sectional view taken along line YY of FIG.

[Explanation of symbols]

1: Vertical shaft, 2 ₁ , 2 ₂ , 2 ₃ , 2 ₄ : Tunnel,
3 ₁ , 3 ₂ , 3 ₃ , 3 ₄ : Lower vertical earth retaining wall, 4 ₁ , 4
₂ , 4 ₃ , 4 ₄ : Upper vertical water stop wall, 5: Horizontal earth retaining wall,
6: Frame, 7: Bottom of excavation.

Claims (1)

[Claims] 1. A shield is started from a vertical shaft provided in a vacant land near an existing ground object, and a tunnel is formed below the existing ground object along the plane contour of an underground structure to be constructed. From the inside, construct a lower vertical retaining wall and an upper vertical retaining wall, lower the groundwater level inside the upper vertical retaining wall, and construct a horizontal retaining wall between the opposing tunnels above the groundwater level. After the horizontal earth retaining wall and the lower vertical earth retaining wall are rigidly joined to form a frame structure with a rigid frame structure, the inside is excavated, and an underground structure is constructed in this excavated portion. How to build a structure.