JP2742709B2 - How to build a ground reinforcement support in the ground - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention is to construct a ground reinforcement support above a large space such as a high-rise building or a warehouse in a deep underground. It is about the method.

[Conventional technology]

To construct a space underground, (a) excavate a portion corresponding to the outer periphery of the underground space from the ground in a groove shape, construct a reinforced concrete wall in the trench, and then construct the inside of the interior surrounded by the wall. A method of excavating and excavating the ground is used. In order to construct an underground space below existing buildings, (b) excavate a vertical hole along the outer periphery of the existing building and attach a supporting pile. A horizontal hole is excavated along the bottom of the building at the upper end of the building, a supporting beam such as reinforced concrete is formed in the horizontal hole to support the existing building, and then the lower part is excavated and the ground is excavated. The soiling method is known as the underpinning method,
To construct a space at a deep depth of 50m or more, (c) excavate an annular tunnel around the underground space, cast concrete into the excavated part, construct a reinforcing ring, A method is known in which a reinforcing ring is stacked and the upper part is gradually formed into an arch shape as a reinforcing ring having a smaller diameter to form a reinforcing wall surface, and then the ground inside is excavated and discharged (see JP-A-64-43699). Have been.

[Problems to be solved by the invention]

In the conventional method (a), when the depth is shallow, the retaining wall can be supported by cutting beams and excavation can be performed vertically, but when the depth is as large as 50 m or more, it is necessary to excavate with an open cut with a glue, The construction requires a site much larger than the underground space, and in urban areas, etc., there is a building, etc., so it is impossible to secure vacant land, so excavation is impossible, and the volume of excavated soil is large and the excavation cost is expensive There is a problem that
Method (b) is to excavate a large-diameter hole for both vertical and horizontal holes that can be used by workers. Therefore, in order to protect existing buildings with huge loads, the injection method for reinforcing the ground and the construction of continuous underground walls are required. Arbitrary location because there is a need for a large amount of necessary and careful construction so as not to affect existing buildings, and there must be a building with an area equal to the area of the underground space If an underground space of any size cannot be constructed, and if the bottom of existing buildings does not exist to a sufficient depth, the size of There are problems that cannot be supported, (c)
The method requires drilling a tunnel because it excavates a tunnel, requiring a large amount of concrete lining.
It takes a long time to complete the construction because the tunnels are stacked in multiple layers,
In addition, when the area of the underground space is large, there is a problem that it is impossible to construct a large underground space because the strength of the members supporting the ceiling portion is small.

The present invention solves the above-described problems, and provides a ground reinforcement support in the ground so that an economical large-depth underground space can be constructed in any place and in any size by a simple operation. The task is to build.

[Means for solving the problem]

In order to solve the above-mentioned problem, the present invention is to erect a large number of tubular bodies having windows at the depth of the hard clay layer in the ground,
Horizontal holes and oblique holes are drilled between the adjacent tubular bodies in the horizontal and oblique directions by a water jet from the window of the tubular body, and these holes and the tubular body are filled with a fluid solidifying agent and solidified. To form a truss-like net structure,
In the case of a permeable ground without a hard clay layer, after the truss-like network structure is solidified, a method of constructing a ground reinforcement support in the ground in which a foamable synthetic resin liquid is injected into the ground is provided. It's something to worry about.

[Embodiment and operation]

An embodiment of the present invention will be described together with the operation with reference to the drawings.

In FIG. 1, a vertical hole 3 reaching a supporting ground 2 is drilled in a ground 1 by an auger boring machine. In this case, as shown in FIG. 5, the vertical holes 3 are arranged at a density corresponding to the geology of the ground 1 in a shape having an area requiring reinforcement. Perforated vertical hole 3
And a tubular body 4 such as a steel pipe is inserted into the supporting ground 2 to be fixed thereto. Around the side surface of the tubular body 4, a plurality of windows 6 are provided at an intermediate portion corresponding to the depth of the hard clay layer 5 in the ground 1, and a high-pressure water pipe 7 is inserted into the tubular body 4 from the ground. A horizontal hole 9 and a slant hole 10 are bored from one tubular body 4 to an adjacent tubular body 4 by dripping the water jet 8 horizontally and obliquely upward and downward from its tip.
(Refer to FIG. 1, FIG. 2, and FIG. 5.) Next, as shown in FIG. 2, a reinforcing material such as carbon fiber or metal fiber was mixed into the tubular body 4, the lateral hole 9, and the oblique hole 10 ( A truss-like network structure 12 is formed by injecting a fluid solidifying material 11 such as cement grout or synthetic resin. In some cases, depending on the strength of the truss-like net structure 12, there is a case 11 'where it is not necessary to inject the fluidized solidified material 11 into the tubular body 4 below the truss-like net structure 12.

Next, the ground reinforcement support is constructed by solidifying the fluidized solidified material 11. Since this ground reinforcing support has a state in which the solidified truss-like network structure 12 and the hard clay layer 5 in the ground 1 are combined, the adhesive force of the hard clay layer 5 and the truss-like network structure 12 are integrated. In order to exhibit the function of supporting the load on the ground 1, the underground space 1 can be constructed by excavating the ground 1 under the ground 1 and discharging the soil from the standing pile 13 as shown in FIG. At this time, when the hard clay layer 5 does not exist and the soil is permeable, the foamable synthetic resin liquid is pressed into the ground, foamed by the moisture in the ground, and penetrated into the ground by the expansion pressure of the synthetic resin itself. A method of solidifying and strengthening the ground can be used.

In the underground space 14, various buildings 15 can be constructed as shown in FIG.

〔The invention's effect〕

Since the present invention erects a tubular body and drills a horizontal hole and an oblique hole from the tubular body by a water jet,
(1) The work is simpler and easier than a worker excavating the inside of a vertical hole and a horizontal hole, (2) no protective work is needed to strengthen the surrounding ground, and (3) the excavation cost is reduced. (4) The construction period can be shortened, and (5) The ground reinforcement support can be constructed by erecting a tubular body from the ground, so that an underground space can be constructed at any place. (6) Since the solidified material in the upright tubular body, the horizontal hole and the oblique hole forms the truss-like net structure in the ground, the ground becomes integral with the truss-like net structure by its adhesive force. It is possible to firmly support the upper ground, not to mention that the ground does not fall due to the shearing resistance of the soil, and (7) it is possible to construct a vast underground space because the construction area is not limited.

[Brief description of the drawings]

FIG. 1 to FIG. 4 are explanatory diagrams each shown in a cut front view,
FIG. 5 is an explanatory diagram shown in a plan view. 1 ... ground, 4 ... tubular body, 5 ... hard clay layer, 6 ...
Window, 8: Water jet, 9: Horizontal hole, 10: Oblique hole, 11: Fluid solidification material, 12: Truss-like net structure

 ──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-2-108799 (JP, A) JP-A-2-108798 (JP, A) JP-A-1-198926 (JP, A) JP-A 64-64 83799 (JP, A)

Claims (3)

(57) [Claims] 1. A tubular body (4) having a window (6) at an intermediate portion is erected in the ground (1) in a horizontal direction by a water jet (8) from a window (6) of the tubular body (4). A horizontal hole (9) and a diagonal hole (10) are formed between the tubular bodies (4) adjacent to each other in a diagonal direction, and flow is caused to flow through these holes (9), (10) and the tubular body (4). A method for constructing a ground reinforcement support in the ground in which a truss-like net structure (12) is formed by filling and solidifying a stiffening material (11). 2. The method according to claim 1, wherein the ground on which the truss-like network structure (12) is formed is a hard clay layer (5). 3. The method for constructing a ground reinforcing support in the ground according to claim 1, wherein the foamable synthetic resin liquid is injected into the ground (1) of the truss-like net structure (12).