JP2780848B2 - Bottom grouting method for concrete structures - Google Patents

Description

[Detailed description of the invention] [Industrial application field] This invention puts concrete structures on a base and joins them together, and injects grout into the gap between these concrete structures and the base. And a bottom grouting method for a concrete structure for filling the gap.

[Prior art] For example, when constructing an underground structure such as a basement or an underground storage, as an alternative to cast-in-place concrete, the present applicant has disclosed in an underground space where the ground has been dug up undisclosed.
Joining and integrating multiple U-shaped concrete structures,
We have devised a means to provide a basement.

4 (A), (B), (C), (D), (E)
It is a figure which shows the process at the time of constructing the said underground building.

When constructing this underground structure, first, as shown in FIG. 4 (A), the ground is dug down to provide a space underground,
The bottom surface of this space is flattened, and concrete is dumped on the bottom surface to form a base 1. Leveling steel pipes 4, 4 for placing concrete structures 2, 3 on the base 1
... is provided. Next, as shown in FIG. 4 (B), a plurality of U-shaped concrete structures 2, 2,. The structures 2, 2, ... are arranged along the axial direction.

Next, as shown in FIG. 4 (C), the concrete structures 3, 3,... Which will be the walls of the rear wall portion of the U-shaped concrete structures 2, 2,. And in advance,
Each of the concrete structures 2, 2,... And the concrete structures 3, 3,.
The PC steel materials 6, 6, ... are inserted into the through holes 5, 5, ...
The steel materials 6, 6,... Are pulled by jacks, and tensile stress is applied to the PC steel materials 6, 6, so that the concrete structures 2, 3 are pressure-welded.

Next, as shown in FIG. 4 (D), the berths 7, 7,... For constructing a house on the underground building are placed on the concrete structures 2, 3.

Next, as shown in FIG. 4 (E), a grout material such as mortar is injected into a gap between the bottoms of the concrete structures 2 and 3 and the base 1 to fill the gap.

In such a general grouting method, as shown in FIG. 5, first, the grout material is not leaked out.
The lower ends of the outer peripheries of the joined concrete structures 2, 3 are surrounded by, for example, a packing 8 made of rubber or the like, and injection pipes 9, 9,... The discharge ports are inserted one by one into the concrete structures 2 and 3 in a row, and the grout material is filled. On the other end side of the concrete structures 2 and 3 of the packing 8, grout material filled from the injection pipe 9 was used to check that the bottoms of the concrete structures 2 and 3 were completely filled. Material discharge hole 10
And place it.

And after filling with grout, concrete structure 2,
The building constituting the house is placed on the reference numeral 3 via the ligaments 7, 7,....

[Problems to be Solved by the Invention] By the way, the grout material is injected into the gap between the concrete structure and the base from one end of the integrated concrete structure, and when the grout material is discharged from the outlet at the other end. When the filling of the grout material is completed, it is determined whether or not the gap between the concrete structure and the base is completely filled with the grout material by discharging the grout material from the outlet. However, when the grout was discharged from the discharge port, it was not possible to confirm whether or not the gap between the concrete structure and the foundation was actually completely filled with the grout.

For example, when filling grout material with one injection tube,
If air bubbles are formed between the base and the concrete structure, the grout material may be injected around the air bubbles and discharged from the outlet. In this case, there is a high possibility that the bubbles will not be discharged even if a certain amount of grout material is discharged from the discharge port.

The present invention has been made in view of the above circumstances,
It is an object of the present invention to provide a method for bottom grouting of a concrete structure capable of reliably filling a gap between a base and a concrete structure with a grout material without any gap.

[Means for Solving the Problems] The method for grouting a bottom of a concrete structure according to the present invention comprises the steps of: placing a plurality of concrete structures on a base in an axial direction thereof, and integrating the concrete structures with each other; Filling a gap between the base and the concrete structure with a grout material, comprising: a bottom grouting method for the concrete structure, the method comprising: placing a plurality of concrete structures at the positions of the base where the concrete structure is to be mounted before installing the concrete structure. The grout material injection pipe is set so that the position of the discharge port is gradually shifted in the axial direction of the concrete structure, and after the concrete structure is installed, the grout material injection pipes are set. And a grout material is filled between the base and the concrete via the vial.

[Operation] According to the above configuration, the positions of the discharge ports of the plurality of grout material injection pipes set in advance below the concrete structure are:
The grout material is spread out and filled around the multiple discharge ports that are displaced because the structure is shifted stepwise along the axial direction of the concrete structure. It is possible to reliably fill the space where there is no possibility of being filled.

Hereinafter, a first embodiment of the present invention will be described with reference to the drawings.

The method for grouting the bottom of a concrete structure according to the first embodiment shown in FIGS.
As shown in FIGS. (A), (B), (C), (D) and (E), a concrete structure devised by the present applicant is joined and integrated to construct an underground structure such as a basement. Components that are applied and are the same as those in the method shown in FIG. 4 and the like are denoted by the same reference numerals and description thereof is omitted.

When constructing an underground structure, as described above, the ground is first dug down, an underground space is provided, the bottom surface of the underground space is leveled, the concrete is thrown away, and the base 1 is provided. A leveled steel pipe 4 (shown in FIG. 4 (A)) for arranging U-shaped concrete structures 2, 2,... Next, four grout material injection pipes 9 are arranged along the axial direction of the concrete structures 2, 2,... As shown in FIG. In this case, the discharge ports 9a of the injection pipe 9 are arranged so as to be shifted stepwise at predetermined intervals.

Next, concrete structures 2 and 3 are installed along the leveling steel pipe 4 in the axial direction, and these concrete structures 2 and 3 are connected to PC steel members 6 and 6 (shown in FIG. 4 (C)).
Press-welding.

Next, as shown in FIG. 1 and FIG. 2, the lower ends of the concrete structures 2 and 3 joined together are stuck with mortar or the like to prevent the grout material from overflowing. next,
The discharge ports 9a, 9 of the respective injection pipes 9, 9,... Of the mortar section 8a for bonding the side faces of the joined concrete structures 2, 3
Six grout material discharge holes 10 are provided at intermediate positions between the positions corresponding to a.

Next, a grout material is supplied to each of the injection pipes 9. The grout material spreads from the discharge ports 9a, 9 ... of each of the injection pipes 9, 9 ... and fills the gap between the base 1 and the concrete structures 2, 3. When the gap between the base 1 and the concrete structures 2 and 3 is filled with the grout material, the grout material overflows from each of the discharge holes 10.

After confirming that the grout material overflows from the discharge holes 10 and 10, the grout material injection is stopped.

As described above, according to the concrete structure bottom grouting method of this embodiment, the concrete structure,
The discharge ports 9a of the four injection pipes 9 arranged in the axial direction of ...
The grout material spreads out from each of the discharge ports 9a, 9a, ... and is injected into the gap between the base 1 and the concrete structures 2, 3, because the 9a ... are arranged stepwise at predetermined intervals. Therefore, the grout material can be filled all over.

Also, by providing the six discharge holes 10 at positions intermediate the positions corresponding to the discharge ports 9a, 9a,... On both side surfaces of the concrete structure, the air between the base 1 and the concrete structures 2, 2 is reduced. It is quickly discharged and there is little possibility that air bubbles are trapped between the foundation 1 and the concrete structures 2, 3.

Further, since the grout material is injected from the four discharge ports 9a, 9a, the injection amount per time is large, and the grout material injection operation can be completed in a short time.

FIG. 3 is a drawing showing a second embodiment of the present invention.

The method for bottom grouting of a concrete structure according to the second embodiment is different from the first embodiment in that a plurality of injection pipes 9, 9 are provided.
Are arranged from one end of the joined concrete structures 2 and 3, whereas a plurality of injection pipes 9, 9 are arranged from both ends. Components that are the same as the components shown are given the same reference numerals, and descriptions thereof are omitted.

In this second embodiment, the injection tube 9 is placed on the base 1,
9 are arranged, three injection pipes 9 from each end
Are arranged along the axial direction of the concrete structures 2, 2,..., And the discharge ports 9a of the respective injection pipes 9 are arranged so as to be shifted stepwise at predetermined intervals. And, as in the first embodiment,
Concrete structures 2 and 3 are installed and joined, and grout is injected.

The method for grouting the bottom of a concrete structure according to the second embodiment has the same effect as that of the first embodiment, and the grout material is more quickly poured by arranging the injection pipes 9 from both ends. can do.

In these examples, the number of the injection pipes 9 was 4
The number of these injection pipes 9, 9... Is determined in consideration of the area of the bottoms of the joined concrete structures 2, 3 and the like, and is limited to four or six. Not something. In this embodiment, the underground structure is applied to the construction by joining the U-shaped concrete structures 2, 2,..., But the bottom grout method of the concrete structure according to the present invention is applied to a plurality of concrete structures on the base. This is a method in which a structure is installed and joined together, and a grout material is injected into the bottom of the concrete structure, and its use is not limited to the construction of an underground structure.

[Effects of the Invention] As described above in detail, according to the method for grouting a bottom of a concrete structure according to the present invention, before installing the concrete structure, a plurality of grout materials are injected into a position of a base on which the concrete structure is to be installed. Since the pipe is set so that the position of the discharge port is shifted stepwise in the axial direction of the concrete structure, the grout material spreads around the discharge port and is filled. Thereby, the possibility that there is no place where the grout material is not filled is low, and the grout material can be reliably injected into the gap between the base and the concrete structure.

[Brief description of the drawings]

1 and 2 are views showing a first embodiment of the present invention. FIG. 1 shows a state in which a concrete structure is placed on a grout material injection pipe arranged on a base. FIG. 2 is a plan view, and FIG. 2 is a perspective view of a concrete structure integrally joined on a base. FIG. 3 is a drawing showing a second embodiment of the present invention, and is a plan view showing a state in which a concrete structure is placed on a grouting material injection pipe arranged on a base, and FIG. A), (B), (C), (D), and (E) are perspective views showing a construction process of an underground building, and FIG. 5 is a plan view showing a conventional bottom grout method of a concrete structure. 1 ... foundation, 2 ... concrete structure, 3 ... concrete structure, 9 ... grout material injection pipe, 9a ... discharge port

Claims (1)

(57) [Claims] 1. A step of placing a plurality of concrete structures on a base in an axial direction thereof and integrating the concrete structures with each other, and filling a grout material in a gap between the base and the concrete structures. A bottom grouting method for a concrete structure, comprising: before installing the concrete structure, a plurality of grout material injection pipes at the position of the base where the concrete structure is to be installed, and the position of the discharge port thereof is a concrete structure. It is set so that it is displaced stepwise in the axial direction of the object, and after the concrete structure is installed, the grout material is filled between the base and concrete through the grout material injection pipes. A bottom grout method for a concrete structure.