JP2733279B2 - Manufacturing method of pile with bag - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a method for manufacturing a ready-made stake having a bag mounted thereon, and particularly to a method for manufacturing cement milk or concrete in a bag mounted on a ready-made stake. The present invention relates to a method for manufacturing a ready-made pile equipped with a bag used for forming an enlarged portion by injection.

(Conventional technology and its problems) Conventionally, a construction method using a ready-made pile having a bag body has been developed in order to express a high vertical bearing force.

As shown in FIG. 1, for example, this pile is a pile in which a bag is attached to the outer periphery of the tip of a ready-made pile. Such a pile is disclosed, for example, in JP-A-63-14925.

This pile is embedded in a hole of a predetermined depth in the soil excavated in advance, and then a solidified fluid such as cement milk, etc., which has been applied with a certain pressure through an injection pipe installed in the hollow part of the pile, is inserted into the bag. It has a structure that can be injected.

The conventional method of mounting the bag body of the pile is to apply an adhesive to the outer peripheral surface of the bag body mounting part, cover the bag body from above, further wind a steel belt for packing from above, and tighten it with a machine, As shown in FIG. 4, two notches 6 were inserted into a fixing bracket 5 arranged on the belt 4 and fixed. However, in such an attachment method, the belt 4 had to be wound three to four times in order to withstand the injection pressure of the caking fluid injected into the bag. However, even if the inflation pressure of the bag body 2 increases due to an increase in the injection pressure or the like, a crack occurs in the notch 6 of the fixing metal 5 and the belt 4 starts to come off from the fixing metal 5 and finally comes off. There was something to do. As shown in FIG. 5, this phenomenon occurs even when the cushioning material 7 is arranged all around the inner surface of the attachment portion of the bag body 2.
Could not be prevented. When such a crack occurs, the belt 4 starts to come off from the fixing bracket 5, and the belt 4
Since the tightening force of the bag decreases, the caking fluid leaks out and the bag 2 does not expand to a predetermined diameter.

(Means for Solving the Problems) The present invention has been made to solve the above-mentioned drawbacks in the prior art, and the belt does not fall out of the fixture even if the injection pressure rises to a relatively high value. Accordingly, it is an object of the present invention to provide a method for manufacturing a pile with a bag, which does not leak the caking fluid and does not require or double the belt.

The present invention relates to a method for manufacturing a pile with a bag, in which the bag is attached to the surface of the pile by tightening a belt, the belt is tightened and fixed by using a fixing bracket having notches at four or more places, and the bag is fixed to the pile. A method for producing a pile with a bag, which is attached to a surface.

 Hereinafter, the present invention will be described with reference to the drawings.

FIG. 1 is a half sectional view showing a state in which a solidifying fluid 3 such as cement milk is pressed into a bag body of a pile in which a bag body 2 is mounted on an outer peripheral surface of a pile body 1 which is a ready-made pile. It is. As shown in this figure, the bag 2 is attached to the outer periphery of the pile 1 by the belt 4 at the upper and lower portions.

FIG. 2 shows an enlarged view of the mounting portion at the upper part of the bag body of the pile shown in FIG. The mounting portion at the lower part of the bag has a similar structure.

Thus, the bag 2 is put on the surface of the ready-made pile 1 and fastened with the belt 4. The shape of the bag 2 is generally cylindrical, and both ends of the bag are shrunk so as to be easily attached to a ready-made pile, a tack is attached, and the contact portion with the band is folded back to form a second portion. You may make it the structure reinforced by weight. The material of the bag is generally made of cloth, and is preferably a cloth bag made of synthetic fibers such as polyamide, polyester, vinylon, and polypropylene from the viewpoint of dehydration and strength of the caking fluid. If a bag capable of dehydrating the water of the caking fluid in this manner is used, a caking fluid such as cement is injected into the bag body of the pile at the time of construction, and a predetermined pressure, for example, 6 to 10 kg / Moisture in the caking fluid is dehydrated through the bag surface by the injection pressure of cm ² , and the caking fluid becomes a dense and strong cured body after curing.

After the bag is put on the ready-made pile in this way, the belt 4 is wound and fixed from above. Generally, a steel belt is preferably used as the belt, and a steel belt for packing is suitable. The belt preferably has a width of about 10 to 500 mm and a thickness of about 1 to 3 mm.

The belt is tightened with a strong force using a tightening machine utilizing hydraulic pressure, pneumatic pressure or the like. At this time, the pulling force of the belt is
800 kg or more is preferable. The fixing of the belt is performed by connecting the upper and lower belts by making a notch 6 in the fixing bracket 5 as shown in FIG. This notch 6 is 4
It is important to put it in more than one place. It is surprising that, when the number of the notches 6 increases in this way, no crack is generated. In addition, it is generally optimal that the notch 6 is generally provided at two positions in each of the upper and lower portions. Aluminum, stainless steel or the like is suitable for the material of the fixing bracket.

In addition, as shown in FIG. 3, if the cushioning material 7 is previously arranged over the entire circumference between the bag body and the pile body of the mounting portion, it becomes possible to withstand a higher inflation pressure. The material of the cushion member 7 may be a foamed material such as polyvinyl chloride, polyethylene, or polyurethane, or a material such as rubber that closes the gap between the bag body and the pile body after band tightening. The width of the cushion member 7 may be any width as long as it is wider than the band width, and is preferably about 50 to 200 mm.

The cushion material 7 may be covered with a bag body after being attached to the pile body surface, or may be previously attached to the bag body. In addition, the cushion member 7 can be read by affixing it to the surface of the pile body with an adhesive or by simply temporarily fixing it with a tape or the like without using an adhesive.

Hereinafter, the present invention will be described in detail with reference to examples.

Example The pile used in this example has the structure shown in FIG. At the lower part, a friction cutter 8 is attached to protect the bag body when the pile is laid down. Pile diameter Di is 350mm,
The pile length is 3m. In addition, an iron pipe having a diameter of 1 inch is provided at the center of the hollow part of the pile as an injection pipe 10, and this iron pipe has a T-shaped portion connected to the inside of the bag so that cement milk can be injected into the bag through this iron pipe. doing.

The material of the bag is nylon 66, the cloth at both ends of the bag is folded back and doubled, and the tack is attached and the diameter of the mounting part is 37.
The structure was set to be 0 mm. The bag used had a diameter D of 600 mm and a length of 2200 mm after the cement milk was injected.

This bag was attached to a ready-made pile according to the attachment method of the present invention. That is, 150mm wide and 10m thick at the mounting part of the ready-made pile
After wrapping a foam of polymethane as a cushion material, the bag was set, and a steel belt for packing was wrapped from above and tightened with a tensile force of 1000 kg. The dimensions of the packing steel belt are 32 mm wide and 0.9 mm thick, with a tensile strength of 90 kg /
mm ² and wound twice. The fixing of the belt was carried out by making four notches in the fixing metal as shown in FIG.

In this way, the pile of the present invention was used as a test specimen 1 and two piles were prepared by a conventional mounting method except that a cushion material was used as shown in FIG. Were cut into three notches, and the three rolls were used as test specimens 2. Ten specimens each were prepared, and cement milk was pressed into a bag body on the ground to perform a comparative test.

As a result, the injection pressure was 10kg for all 10 piles
/ cm ² , the bag did not come off from the pile, there was no leakage of cement milk, and the bag expanded sufficiently to a predetermined diameter, whereas the specimen 2 out of 10 The belt began to come off from the fixture with the injection pressure of about 6 kg / cm ² from five piles and cement milk began to leak, and the belt came off between 7 and 10 kg / cm ² and the bag did not expand to the prescribed diameter. .

(Effect of the Invention) In the pile with the bag attached by the method of the present invention, even if the injection pressure reaches 10 kg / cm ² , there is no defect in the fixture, and the bag comes off or solidifies. The bag can be inflated to a predetermined diameter without leakage of the fluid.

[Brief description of the drawings]

FIG. 1 is a half cross-sectional view when a solidifying fluid is injected into a bag body of a pile manufactured by the mounting method according to the present invention to expand and inflate the bag body, and FIG. 2 is a bag shown in FIG. FIG. 3 is an enlarged sectional view of the bag mounting portion A shown in FIG. 1, and FIG. 4 is a mounting bracket of the bag mounting portion of the pile manufactured by a conventional mounting method. FIG. 5 is an enlarged sectional view of FIG. 1 is a pile, 2 is a bag, 3 is a solidifying fluid, 4 is a belt,
Reference numeral 5 denotes a fixing bracket, 6 denotes a cutout, 7 denotes a cushion material, 8 denotes a friction cutter, 9 denotes an adhesive, 10 denotes an injection pipe, and A denotes a bag mounting portion.

Claims (1)

(57) [Claims] 1. A method of manufacturing a pile with a bag, wherein the bag is attached to the surface of the pile by tightening a belt, the belt is tightened and fixed by using a fixing bracket having notches at four or more places. Method for manufacturing a pile with a bag, characterized in that the pile is attached to the body surface