JPH02240320A - Construction method of cast-in-place concrete pile - Google Patents

Abstract

PURPOSE:To make it possible to cut off easily an extra fill section without generating noises or dust by coating main reinforcements in the extra fill section with coating covers, and using a reinforcing cage having a partition cover capable of opening and shuttling to the inside of the main reinforcements of the lower part of the extra fill section. CONSTITUTION:Main reinforcements in an extra fill section 3 are respectively coated with coating covers 4, a partition cover 5 capable of opening and shutting is mounted to the inside of main reinforcements 2 of the lower part of the extra fill section 3 in a state of opening to erect into an excavated hole (m), and concrete (n) is placed into the hole (m) from a tremie pipe T. Then, a handle section 6a of a pulling cord is pulled, and hanging cord 5b is cut off to blockade an opening 5a of the partition cover 5 into the concrete (n). The main reinforcement 2 in the extra fill section 3 are separated and insulated from the concrete (n) by the coating covers 4, and pile bodies 1a are separated and insulated from the extra fill section 3 by the partition cover 5. According to the constitution, the extra fill section of a pile head can be easily cut off.

Description

Detailed Description of the Invention (Industrial Field of Application) The present invention provides an on-site construction method for transmitting the load of a superstructure to the supporting ground when there is no ground near the ground surface that can directly support the load of the superstructure. It concerns the construction method of concrete piles.

(Prior art) If there is no ground that can directly support the load of the superstructure near the ground surface, piles that reach the supporting ground are driven into the ground to transfer the load to the supporting ground. There is a pile foundation method.

This pile foundation construction method includes hammering construction method, embedded pile construction method, cast-in-place concrete construction method, etc., but in recent years, the following methods have been developed: ■ It is possible to construct long piles (50 to 60 m) and piles of arbitrary shapes, and ■ It is relatively easy to dispose of residual soil. For these reasons, the cast-in-place concrete pile method is frequently used. It is used.

This cast-in-place concrete pile construction method involves erecting a reinforcing bar cage into a hole drilled in the ground, filling it with concrete, and after the concrete has hardened, the excess portion of the pile head that protrudes above the ground is removed for strength reasons. The situation had been resolved.

The excess portion of the head of the sleeper was cut out using static crushing agents, drilling tools, etc.

(Problem to be solved by the invention) However, when cutting out the excess portion of the head of the sleeper, it is not easy to cut out using a static crushing agent because vertical cracks occur, and when drilling iwatsuki, a large amount of noise and a large amount of dust are generated. However, there were problems in that it not only had a negative impact on the surrounding environment, but also took a lot of time.

The present invention has been made in view of the above-mentioned problems, and its purpose is to provide a cast-in-place concrete pile in which the excess portion of the pile head of a cast-in-place concrete pile can be easily removed in a short time without generating noise or dust. -I. To provide a pile construction method.

(Means for Achieving the Object) In order to achieve the above object, the structure of the present invention is such that the main reinforcing bars of the reinforcement section are each covered with a covering cover, and the main reinforcing bars at the bottom of the reinforcement section are covered with covers. A reinforcing bar cage with a partition cover that can be opened and closed is installed in a hole drilled underground, and the core is filled with concrete, and then the partition blade bar is immediately closed in concrete and piled. This invention consists in a construction method for cast-in-place concrete piles, which is characterized by insulating the main body and the extra heap.

(Function) According to the above configuration, the extra layer and the main reinforcement are separated by the covering cover, and the pile main body and the extra layer are separated by the partition cover, so the extra layer is separated from the main reinforcing bar by the partition cover. It can be easily cut off from

(Example) Hereinafter, an example of the method for constructing cast-in-place concrete piles of the present invention will be described based on the drawings.

Figures 1 to 5 show the process diagrams for cast-in-place concrete 1 to pile A. First, as shown in Figure 1,
A hole m is excavated underground, and reinforcing bars n1 are erected in the core m.

The reinforcing bars fil are composed of a plurality of main reinforcing bars 2 and tie bars 2a arranged at appropriate intervals outside the main reinforcing bars 2,
Each main reinforcement 2 of the upper reinforcement section 3 is covered with a cover 4, and a partition cover 5 is housed inside the lower end of each main reinforcement 2 of the upper reinforcement section 3.

Further, a spacer is interposed between the main reinforcement 2 of the extra portion 3 and the hole m.

The partition cover 5 is a semicircular or crescent-shaped sheet made of soft synthetic resin with an opening 5a that can be opened and closed, and the outer periphery is fixed to the main reinforcing bars 2, and the reinforcing bars are attached with the opening 5a open. f! The string that can be easily cut on the inner surface of 1 is string 5b.
It is attached with etc. Further, a drawstring 6 for closing the opening 5a is provided at the upper end of the opening 5a, and a pull portion 6a of the drawstring 6 passes through the outside of the strap 2a and connects to the excess portion 3.
It is locked to the upper end of the main reinforcement 2.

The partition cover 5 is not limited to the one described above as long as it is a sheet with excellent waterproof properties.

Next, as shown in FIG. 2, concrete n is injected into the hole m in which the reinforcing bars n1 have been installed through a tremie pipe to form a pile body 1a.

As shown in FIG. 3, after the concrete n is filled up to the excess portion 3 directly above the partition cover 5,
By alternately pulling both the handle parts 6a, the hook is attached to the string 5.
b is cut, the opening 5a of the partition cover 5 is closed in concrete, and the pile main body 1a and the heap portion 3 are insulated.

In this case, the partition cover 5 is blocked in the concrete, so it may not be completely blocked, but even in that case, it is possible to insulate the pile body 1a and the extra layer 3.

Next, as shown in FIG.
By destroying the surrounding surface of the pile body 1a in which is buried,
The concrete in the excess portion 3 can be easily cut out. this is,
The main reinforcing bars 2 of the extra portion 3 are covered with the covering cover 4 and the main reinforcing bars 2
This is because the pile main body 1a and the extra heap portion 3 are separated by the partition cover 3.

(Effects of the Invention) The present invention has the following effects by having the above configuration.

■ The reinforcing bar cage, in which the main reinforcing bars of the extra heap are each covered with a covering cover, and a partition cover that can be opened and closed is attached to the inner side of the main reinforcing bars at the bottom of the extra heel, is inserted into a hole drilled underground. A pile in which the partition cover is buried after the concrete has hardened, by immediately closing the partition cover in concrete to insulate the pile body and the extra heap after filling concrete for erection and coreization. The excess portion can be easily cut off from the pile body by simply destroying the peripheral surface of the body, and generation of large noise and dust can be prevented.

■ Cast-in-place concrete 1 - Since the excess portion of the pile can be easily cut out, the construction period can be shortened and the construction cost can be reduced.

[Brief explanation of drawings]

1 to 5 are process diagrams of the method for constructing cast-in-place concrete piles of the present invention, and FIG. 6 is an enlarged plan view of the method. In the figure, A: Cast-in-place concrete 1: Reinforcing bar capacity 2: Excess portion 3: Covering cover 4: Partition cover 5: Main reinforcing bar
m; hole n: concrete. Figure 4 7A Figure 5

Claims (1)

[Claims] A reinforcing bar cage is constructed in a hole drilled underground, in which the main reinforcing bars of the extra heap are each covered with a covering cover, and a partition cover that can be opened and closed is attached to the inner side of the main reinforcing bars at the bottom of the extra heel. 1. A method for constructing a cast-in-place concrete pile, characterized in that after the hole is filled with concrete, the partition cover is immediately closed in concrete to insulate the pile body and the extra heap.