JP2572753Y2 - Pile-free joint structure - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a non-welded joint structure for concrete piles to be cast in the ground.

[0002]

2. Description of the Related Art The conventional joint structure of a pile is a welding joint. Such welding requires a welding technician, the work is governed by the weather, and the welding strength depends on the skill of the operator, which is unreliable, and the ratio of welding time is very large. In order to solve this, Japanese Unexamined Utility Model Publication No. 3-83224 discloses a non-welded joint structure for piles. In this technology, an annular groove is provided in the outer diameter near the butt end of the pile, a split inner ring is engaged with this groove, and an outer ring is fitted to the outer diameter by tightening the inner ring with a cylindrical taper. It was done. This joint structure has an outer diameter of 30
It can be applied to piles of 0 to 1000 mmφ, has advantages such as easy assembly, no need for on-site welding, and the ability to standardize the dimensions and precision of joints to easily produce products of constant quality. .

[0003]

As described above, the non-welded joint structure for piles has many advantages. However, since the inner ring is tightened by the cylindrical taper ring, the structure is configured so that the taper is tightened in the pile driving direction. You. Then, the outer ring has an outer diameter larger than the outer diameter of the pile, and when the pile is driven, a push-up force by the ground is further applied in a tightening direction.
At this time, the extra tightening force applied to the outer ring generates an extra hoop tension in the outer ring, which may cause plastic deformation of the outer ring.Therefore, it is necessary to limit the hoop tension to within an allowable stress level. is there.

An object of the present invention is to develop and provide a pile-free welded joint structure which solves the above-mentioned problems.

[0005]

According to the present invention, a flange is provided at an end of a pile to be connected, and a split inner ring which is integrated by tightening the upper and lower flanges in the longitudinal direction of the pile is externally fitted to the upper and lower flanges. Then, a cylindrical taper is provided on the outer diameter of the inner ring, and a pile-free welded joint structure for joining the pile by tightening the inner ring by externally fitting an outer ring having an inner diameter taper fitted to the cylindrical taper, The lower end of the outer ring at the specified tightening position of the outer ring is dimensioned such that the lower end of the outer ring is higher than the lower end of the inner ring, and the protective ring abuts on the lower end of the inner ring and has an outer diameter equal to the outer diameter of the outer ring. A non-welded joint structure for a pile, which is fitted to a lower pile.

[0006]

[Function] In the non-welded joint structure of a pile to which the present invention is applied, an axial thrust is applied to the outer ring when driving the pile because the diameter of the outer ring is larger than the outer diameter of the pile. In the present invention, this thrust is received by the protection ring. The protection ring is loosely fitted to the outer diameter of the lower pile, abuts against the lower end of the inner ring during pile driving, and has the same outer diameter as the outer ring. It is supported by force and has the effect of supporting the thrust received from the ground on the inner ring and protecting the outer ring from applying this thrust.

For this protection to work effectively, the lower end of the outer ring must be above the lower end of the inner ring when the outer ring is tightened to the outer diameter of the inner ring.

[0008]

1 shows a pile-less welded joint structure 1 of a pile according to the present invention. At the lower end of the upper pile 1a, a flange 2a having an inclined portion 3a is attached to the upper outer periphery, and at the upper end of the lower pile 1b, a flange 2b having an inclined portion 3b is attached to the lower outer periphery, and outside the flanges 2a and 2b. Outer diameter, and inclined portions 3a,
3b is pushed up and down to integrate the flanges 2a2b.
The split inner ring 3 is externally fitted. The outer diameter of the inner ring 3 is
The upper pile side has a large-diameter cylindrical taper. This cylindrical taper is 1/20. The outer ring 5 is fitted to the outer diameter. The outer ring 5 has a cylindrical taper 6 on the inner diameter, and is fitted to the outer cylindrical taper 4 of the inner ring 3. Outer ring 5
When the outer ring 5 is fitted to the inner ring 3 with a regular pressing force, the lower end of the inner ring 3 is dimensioned to be higher than the lower end of the inner ring 3. Table 1 shows an example of the manufacturing dimensions of the outer ring and the generated strain. Table 1 defines the fitting pressure (jack pressure) of the outer ring for each pile diameter, and the strain is 300 × 10 so as to satisfy the long-term and short-term stresses in all cases.
^The inner diameter of the outer ring was set so as to generate a hoop tension of about ^-6 . When the manufacturing tolerance of the flange and the inner ring is +1.2 mm to -0.45 mm, the tolerance of the position of the outer ring in the axial direction is about ± 8.5 mm. Therefore,
If the length of the inner ring is longer than the length of the outer ring by 20 mm, the lower end of the outer ring is higher than the lower end of the inner ring in all cases.

Note that δh in Table 1 shows the amount of change between the position before and after the outer ring 5 is fitted when the outer ring 5 is fitted. Next, the protection ring 10 is externally fitted to the lower pile,
The inner ring is brought into contact with the lower end, and its outer diameter is made substantially equal to the outer diameter of the outer ring. The degree of fitting outside the lower pile may be loose fitting. For this reason, the position holding set bolt 11
It is preferable to provide the following. The outer diameter of the protection ring 10 may be equal to the outer diameter of the outer ring 6. The load received by the protection ring varies depending on the diameter of the pile, the stratum condition, the impact driving condition, and the like, but the upper limit may be designed to be about 20 tons.

FIG. 2 shows a modification of the shape of the protection ring of FIG. 1. Depending on the positional relationship between the inner ring 3 and the outer ring 5, the protection ring 10 is formed so as to fit the outer diameter of the inner ring 3. It may be determined appropriately, for example, by providing a taper at the lower end of the outer diameter of the protection ring 10.

[0011]

[Table 1]

[0012]

[Effects of the Invention] According to the present invention, a non-welded joint structure of a pile, which is easy to assemble, does not require on-site welding, and which can standardize the dimensions and accuracy of the joint and easily manufacture a product of constant quality. Since the hoop tension of the outer ring is prevented from becoming excessive in the above, the outer ring can be held within the allowable stress that does not cause plastic deformation, and it is also applicable to piles on gravel layers and gravel layers An excellent effect is achieved.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a non-welded joint structure of a pile according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view illustrating a non-welded joint structure of a pile according to an embodiment of the present invention.

[Explanation of symbols]

1a, 1b pile 2a, 2b flange 3 inner ring 4 taper 5 outer ring 6 taper 7, 8 lower end 10 protection ring

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Hiromichi Sugami 3-18-16 Towa, Adachi-ku, Tokyo (72) Inventor Hirofumi Kato 5-10-3 Takinoi, Funabashi-shi, Chiba (72) Inventor Author Satoru Yamada 1-400, Yoshino-cho, Omiya City, Saitama Prefecture 14 (72) Inventor Hiroshi Kasahara 4-57-15, Higashi-Omiya, Omiya City, Saitama Prefecture (58) Fields investigated (Int. Cl. ⁶ , DB name) E02D 5/24 103

Claims (1)

(57) [Scope of request for utility model registration] 1. A flange fixed to an end of a pile to be connected, and a two-part flange having an outer fitting on the upper and lower flanges, a slope for tightening the flange in a longitudinal direction of the pile, and a cylindrical taper on an outer diameter. A non-welded joint structure for a pile comprising: an inner ring; and an outer ring having an inner diameter taper, which is externally fitted to the inner ring, pressed in the axial direction of the pile, and tightens the inner ring to integrally join the pile. The ring is dimensioned so that the lower end of the outer ring at the specified tightening position is higher than the lower end of the inner ring, while the lower pile abuts against the lower end of the inner ring and has the same outer diameter as the outer diameter of the outer ring. A non-welded joint structure for a pile, wherein a protective ring having a diameter is loosely fitted.