JPH02140322A - Bag body to be fitted to existing pile - Google Patents

Abstract

PURPOSE:To prevent a bag body from being slipped off a band by making the opening periphery of the bag body covering the outer periphery of the tip section of an existing pipe thick and locating the opening periphery at the outside end section of a fastening band. CONSTITUTION:A bag body 2 uniformly draw-molded so that the opening periphery (a) of a bag body 2 is made thick and the initial diameter of a band fastening section (b) is made slightly larger than the outer diameter of a pile 1 is set on the outer periphery of the tip section of the pile 1. The inside portion of the opening periphery (a) is fastened and fixed by a steel band 5 with a high tensile force. Hydraulic slurry is filled by pressure into the bag body 2 through a filling pipe and hardened to form a hardened body 8.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a bag that is attached to a ready-made pile, and more specifically, it is attached to the outer peripheral surface of the tip of a ready-made pile, and is attached to the outer peripheral surface of the tip of a ready-made pile. The present invention relates to a bag in which slurry is injected to form an enlarged portion, and particularly to a bag for attaching ready-made stakes that prevents the bag from slipping through a band.

[Conventional technology]

Piles that can be constructed in narrow spaces and have a high bearing capacity have been developed as building foundations for narrow areas such as urban areas. A bag body 2 was attached to the outer circumferential surface 11 of the tip. Such piles are known, for example, from Japanese Patent Application Laid-open No. 62-103.
This is shown in Publication No. 25. The bag body used for this type of pile has a structure that it is attached and fixed to the ready-made pile by a band 5 through an adhesive 3 and a cushioning material 4 on the outer peripheral surface of the tip of the pile body 1, as shown in FIG. 11. In the cough bag, the thickness of the fabric at the opening periphery and the band tightening area were the same or approximately similar.

After this pile is embedded in a pre-drilled hole at a predetermined depth in the soil, water is applied under a certain pressure through an injection pipe installed in the hollow part of the pile inside the bag, as shown in Figure 11. Hard slurry 7 is injected.

[Problem to be solved by the invention]

However, in a bag with such a structure,
Even if an adhesive or the like is used, there is a problem that the bag body 2 slips through the band 5 due to the injection pressure of the hydraulic slurry during pile construction, and the hydraulic slurry 7 tends to leak.

SUMMARY OF THE INVENTION An object of the present invention is to provide a bag for attaching a ready-made stake, which eliminates the drawbacks of the prior art and can easily and effectively prevent the bag from slipping through the band.

[Means to solve the problem]

In view of the above-mentioned current situation, the inventors of the present invention have arrived at the present invention as a result of intensive research focusing on the relationship between the band tightening area and the fabric thickness at the peripheral edge of the opening.

The present invention injects hydraulic slurry through an opening in a bag that covers the outer periphery of the tip of a ready-made pile, tightens the peripheral edge of the opening to the pile with a band, hardens the slurry, and forms an enlarged part in the shaft. The bag for attaching ready-made piles is characterized in that the opening peripheral edge of the bag is thick and is located at the outer end of the band.

The ready-made pile of the present invention is 1. a formed concrete pile, and does not require the presence or absence of a hollow section;
It is more preferable to have a hollow structure and include an injection pipe 6 as shown in the figure.

Further, the strength of the ready-made piles only needs to be in accordance with the bearing capacity design, and there are no particular limitations on the presence or absence of reinforcing devices such as reinforcing bars.

In the present invention, the state in which the outer periphery of the tip of the antibody is covered means that the tip of the antibody is attached and fixed with a bag in an openable state as shown in FIG. Any material that can form a bulbous protrusion integrated with the antibody tip may be used, such as one in which a bag is attached and fixed with the tip closed. However, from the viewpoints of ensuring the normal expanded shape of the bag in the soil, preventing damage to the bag when embedding antibodies in the soil, ensuring pressure resistance of the bag, and manufacturing cost of the bag, etc. As shown in FIG. 2, it is more preferable to use a structure in which the upper and lower parts of the bag are attached and fixed by hands so that the antibody tip can be released.

Next, although the bag body of the present invention is generally cylindrical in shape, both ends of the bag body may have a draw-molding structure, a draw-down structure, or a contracted structure so that it can be evenly attached to ready-made stakes, or a hand-held structure. The contact portion may be reinforced by folding back the bag and making it double. As a means of obtaining a cylindrical shape, any method may be used, such as sewing sheets, a ventilation structure with ears, seamless bag weaving using a Paff1 shuttle or a circular loom, etc. From the viewpoint of improving the adhesion of the bag to the surface, it is most preferable to use seamless bag weave, which has a uniform fabric thickness over the entire circumference.

The material of the bag is cloth, and from the viewpoint of dehydration properties and strength of the hydraulic slurry 7, cloth made of synthetic fibers such as polyamide, polyester, polyvinyl alcohol, polyolefin, aromatic polyamide, etc. is preferable.

When a dehydrating bag is made in this way, a hydraulic slurry such as a cement-based slurry is injected into the antibody bag during construction, and the water in the hydraulic slurry is removed by a predetermined injection pressure (for example, 3 to 12 kg/cni). Water is removed through the bag surface, and the hydraulic slurry becomes a dense and strong hardened body 8 after hardening.

In the present invention, the hydraulic slurry refers to a cement I-mixture in a fluidized state, and typical examples include cement milk, mortar, and concrete. The mixing ratio of water and additive materials to be mixed with cement can be determined by comprehensively considering the required material strength of the cured product, operability during injection, material cost, abrasion resistance strength of the fabric, water permeability of the fabric, etc. desirable.

In addition, if the enlarged part of the pile can be integrated with the ready-made pile and form a bulbous projection at the tip of the pile, its shape may be a simple bulbous shape or it may have multiple irregularities. There may be.

The bag opening in the present invention refers to the opening 9 on one or both sides of the cylindrical body, as shown in FIG. 2 or 3.

Further, the peripheral edge of the opening in the present invention is, for example, a portion corresponding to A in FIG. 1, and in the present invention, the belt tightening is located at the outer end of the corresponding portion.

In the present invention, the state of wall thickness means that at the initial thickness of the fabric, when the band is tightened, the increase in the thickness of the fabric at the peripheral edge of the opening relative to the fabric thickness at the corresponding area is 3 mm or more and 15 mm or less, preferably 5 mm or more and 12 mm or less. ■ 1 or less, more preferably 7 dragons or more 10
A state of being lower than a dragon.

If the incremental thickness T of the fabric around the opening does not reach 3 mm,
Due to the high internal pressure applied to the bag, the fabric that forms the opening periphery is tightened, causing problems such as slipping through the narrow gap between the belt and the antibody, causing hydraulic materials such as cement milk to leak out, and if the diameter exceeds 15 mm. Although the purpose of preventing the bag from slipping out of the belt is achieved, problems such as a decrease in handling properties and an increase in processing cost arise because the opening peripheral portion becomes extremely bulky due to the thick wall processing. In other words, the incremental thickness of the fabric around the opening is 1511 or more than 3.
By doing the following, the purpose of the present invention, which is to prevent the bag from slipping through, can be achieved without impairing the performance or the like.

As a means to increase the apparent thickness T of the fabric around the opening, first, as shown in FIG. Second, as shown in Figures 5 to 7, the fabric is folded into a laminate, or the relevant part is made into a multilayer structure, or the fabric is made denser.The third is As shown in FIG. 8, an example of a method is to integrate an elastic material such as a rubber backing 13 with anti-slip properties into the fabric forming the opening periphery by sewing or welding, as appropriate. You just have to choose a reasonable method for the amount. On this occasion,
In order to prevent the thick fabric from flattening, when a rope-like object is inserted into a passage formed by folding the fabric as shown in Fig. 4, the rope-like object becomes flat due to external pressure and forms a band. In order to prevent the fastening from slipping through the parts, it is preferable to use a highly rigid material such as a monofilament rope, cotton, hemp rope, or wire rope.

In this case, whether the built-in rope-like object is completely or partially embedded, it is sufficient that it is integrated with the fabric, and the ends of the rope-like object are not joined. It may be open or closed, as long as it does not leave the passage.

In addition, when making the fabric itself thicker, such as by folding and laminating the fabric, multilayer structure arrangement method, high-density method, etc., the thicker part can be coated with hardening resin, adhesive, or sizing agent. It is desirable to harden the material by impregnating or painting it to provide resistance to deformation when external force is applied.

In addition, in order to make the bag body more effective in preventing the bag from slipping out, the bag body of the ready-made pile l is attached to the part (
For hand tightening, it is extremely effective to process a concave part 10 or a convex part with a depth h on the outer peripheral surface for the purpose of preventing the band from sliding, and it is even more preferable to use it in combination with antibody processing. .

[Effect]

Next, the mounting manner and effects of the bag according to the present invention will be explained.

In FIG. 1, the opening peripheral portion A is thickened, and
Band tightening is performed by setting the bag body 2, which has been uniformly drawn and molded so that the initial diameter of the corresponding part opening is slightly larger than the outer diameter of the pile body 1, on the predetermined outer peripheral surface of the ready-made pile tip. A predetermined portion inside the opening periphery is tightened and fixed using a band steel hand 5 with high tension. The standard of the steel band hand to be used at this time, the number of tightening, and the tension of tightening should be determined appropriately according to the necessary injection pressure, and should not be limited, but for reference, for example, hydraulic slurry Injection pressure of 3~
If it is 12kg/cnl, generally the width is 10~5Q.
Made of steel with a thickness of 1 to 3 mm, the number of pieces is 1 with 1 light.
~3 pieces, and the tightening tension is preferably about 500 to 3,500 kg. This tightening force may be realized as a combined force of one or more bands.

Next, as mentioned above, a highly fluid hydraulic slurry 7 such as cement milk is injected under pressure from the ground side through the injection pipe 6 located in the center of the ready-made pile with a bag attached to the tip ( The bag expands and expands as the injection progresses.

At this time, an extremely large tensile force is applied to the fabric of the bag in the longitudinal direction of the bag, so the bag exhibits a behavior of sliding between the hand and the antibody surface. However, in the bag of the present invention, Since the peripheral edge of the opening is thick, the sliding of the bag is stopped at the transition boundary line to the thick part, and the bag can be prevented from slipping through. Therefore, the injection pressure durability of the bag according to the present invention is not due to slippage from the band portion of the bag, but rather to rupture of the bag itself, fabric breakage at the transition boundary to the thick part, or slipping of the hand, etc. Slipping will depend on other factors.

Next, the effects of the present invention will be explained in detail with reference to Examples, but the present invention is not limited to the Examples in any way.

〔Example〕

Example 1 The pile used in the experiment had an outer diameter of 350 mm, a pile length of 3 m, and a straight outer peripheral surface. In addition, a PVC pipe with a diameter of 1 inch is placed in the center of the hollow part of the pile as an injection pipe, and this PVC pipe has a T-shaped part that communicates with the inside of the bag so that cement milk can be injected into the bag through this PVC pipe. are doing.

The bag body is made of endless plain-woven tubular fabric made of nylon-66.
The thickness is 1.5 mm, and the band tightening on both ends is a drawing molding type with a diameter close to the antibody outer diameter.The dimensions are 6 Q Oam in diameter and 2200 in length after cement milk injection.
am was used. Both ends of the cylindrical fabric are folded back to form a double structure, and a rigid rope made of polypropylene monofilament J and having a diameter of 3 mm, 10 mm, and 15 mm is inserted into the passage, and the band is tightened using the fabric in the corresponding area. Test specimens were prepared in which the apparent incremental thickness of the opening peripheral fabric relative to the thickness (double state) was 3, 10, and 1511, respectively.

Next, to attach the antibody bag, the bag was placed in the bag, and a steel band was used as a belt from above the bag and tightened with a tensile force of 1000 kg to attach the bag to the antibody. Cement I-milk was injected into the bag through the injection tube while the composite was on the ground, and the bursting pressure level of the bag was evaluated.

The results are shown in Table 1, and in both cases the injection pressure was 10 kg/
Even when the bag expanded at the cutting table, there was almost no leakage of cement milk, and although the hand shifted to the inside side for the first time at the 11 kg/ant table, no slippage of the bag was observed. Furthermore, there was no problem in attaching the bag to the antibody.

Example 2 The shape of the part for attaching the antibody bag to the depth h = 10 am
A ground experiment was conducted using the same antibody and bag as in Example 1, except that the concave structure had a width β of 100 mm.

The results are shown in Table 1, and the injection pressure was 13 kg/
Even when the bag expanded on the ctA table, there was almost no leakage of cement milk, and there was no problem in attaching the bag to the antibody.

Comparative Example 1 Using a stake with the same structure as in Example 1, a bag with an opening peripheral fabric with an incremental thickness of 0 (no rigid rope inserted) and a rigid rope with a diameter of 2.20 mm were inserted,
Similar ground experiments were conducted using test specimens with the same configuration except that the incremental thickness was 2.20 mm.

The results are shown in Table 1, and the injection pressure is 6 for the case where the incremental thickness is 0.
．． At 0 kg/-, the band begins to be pushed up by the expansion of the bag; 7. Okg/cnt was reached and the bag slipped through, resulting in cement milk leaking.

On the other hand, the injection pressure of 21 is 7.0 kg/c++t
Then the hunt started to shift, and when it reached 7.5 k+r/cut, the bag came loose and cement milk leaked. In addition, the injection pressure for the 201m one is 11kg/cnT.
Even though the bag did not slip through, there was a problem with the ease of installation.

As is clear from the above results, the products of the present invention in which the incremental thickness of the fabric around the opening was 31 mm or more and 15 mm or less exhibited high injection resistance and had no problems with the bag's fitability. However, if the incremental thickness is less than 3 ms or 1511
In each of the above cases, the results were problematic due to insufficient pressure resistance, poor fitability, etc.

Below margins ◎ ・・・・・・ ○ ・・・・・・ △ ・・・・・・ × ・・・・φ− 1.Excellent Good Fair Slightly Poor Poor Table [Effects of the Invention] The bag body of the present invention is as follows: Since the opening periphery has a thick wall structure, the antibody and the bag will not come off or shift even if the injection pressure of the hydraulic slurry that is press-fitted into the bag is higher than that of conventional bags. There is no leakage of hydraulic slurry due to this. Therefore, it is possible to greatly inflate the bag and obtain a high supporting force.

In addition, if the antibody bag is attached with a concave structure,
There is no band displacement at the mounting part, and there is no leakage of hydraulic slurry until a higher injection pressure is reached, dramatically improving the supporting force of the support pile.

[Brief explanation of the drawing]

FIG. 1 is a partial half-sectional view of an example of the present invention when the bag is attached to an antibody and expanded and inflated, and FIGS. 2 and 3 show how the bag is attached to the tip of the antibody. Cross-sectional view showing an example, No. 4
8 are vertical cross-sectional views of the fabric around the opening of the bag according to the present invention, showing an example of the thickening process of the opening periphery of the bag according to the present invention. FIG. FIG. 10 is a half-sectional view showing a state in which a bag according to an example of the present invention is attached to an antibody having a recessed part.
The figure is a half-sectional view when a conventional bag is attached to an antibody and the bag is expanded and inflated, and FIG. 11 is a partially enlarged half-sectional view of the bag attachment part of FIG. 10. l... Ready-made stake, 2... Bag body, 3... Adhesive, 4...
... cushion material, 5 ... band, 6 ... injection pipe,
7... Hydraulic slurry, 8... Cured body, 9... Bag opening portion, 10... Concave portion, 11... Antibody outer peripheral surface,
12... Rope-like object, 13... Rubber-like banking,
A...Opening periphery, opening...Band tightening part, T...
- Incremental thickness.

Claims (1)

[Claims] (1) Hydraulic slurry is injected through the opening of the bag that covers the outer periphery of the tip of the ready-made pile, the peripheral edge of the opening is tightened to the pile with a band, and the slurry is hardened to provide an enlarged part on the pile. 1. A bag for attaching ready-made piles, characterized in that the opening peripheral edge of the bag is thick and is located at the outer end of the band.