JP2007077695A - Pile fastening structure and fastener used therefor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a pile fastening structure or the like capable of corresponding also to big rotary torque and impact, etc. in the case of rotation. <P>SOLUTION: The pile fastening structure is equipped with fastened metal fittings 2 having tapered flange sections 2a in the fastening end sections and integrally formed in each fastening end section between two circular pipes A and B to be fastened, a fastening metal fitting 1 having tapered surfaces corresponding to tapers of the flange sections 2a in interior surfaces 1d and 1e opposed to a recess section 1A, abutting each fastening end section and holding the flange section by the recess section 1A and a bolt 3 placed so as to pass through the abutting surface of each fastened metal fitting 2 by holding/fixing the flange sections in a state to abut each flange section, the fastening metal fitting 1 is pulled near to each fastened metal fitting section 2 side by the bolt 3 to constitute the pile fastening structure holding/fixing both flange sections 2a, such a recess section 2k that one space G is formed in a state to face/abut on the each abutting surface 2b is correspondingly provided, and in the case of fastening, an engaging body F of a form corresponding to the space G is placed in the recess section 2k. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a pile fastening structure for fastening between pipes of piles disposed in the ground mainly for supporting an upper structure such as a building in the field of construction and civil engineering, and these piles. The present invention relates to a fastener suitable for a fastening structure between circular pipes including

At the construction site or civil engineering site, the ground where the superstructure such as a building is made for the purpose of strengthening the ground is a steel pipe or concrete pipe of a predetermined length (in this specification and claims, it is also referred to as “pipe”). The pile for soil is arranged in sequence. The pile is placed in the soil by screwing with a screw pile, by placing a pile with a driving device, or by inserting a pile into the drilled hole.
The arrangement of piles in the soil has the following technical problems. In the following, the case of screwing will be described as an example. Generally, the length of the ready-made pipes that make up the pile is shorter than the screwing (driving) depth, so multiple pipes are tightened sequentially in the longitudinal direction on site. Thus, it is generally performed to screw in one pile having a desired length.

  And conventionally, fastening between the fastening ends of the pipes constituting the screw pile used in the screwing method is different from the piles of other methods, due to the transmission of rotational torque, the fastening part is very large `` Since the torsional stress and shearing stress are applied, and in some cases the stress is applied with an impact force, this is performed by welding that is excellent in torsional stress, shear stress and impact resistance. Or by forming a screw on the outer periphery of one pipe and the inner periphery of the other pipe, and screwing with a screw.

  However, in the former case, the reliability of the welded part due to on-site welding, the work depends on the weather, etc., and the pile welding work period, the skilled worker of welding is attached to the site. There are problems in workability and economy, such as things that must be avoided. On the other hand, the latter case is not suitable because a screw is formed at the end of the pipe by machining, which is expensive in price and demands for cost reduction after the bubble collapse. Further, since the thickness of the screwed portion becomes about ½, there is a possibility that the strength is insufficient in this portion.

  By the way, when the present inventor experimented about fastening between pipes, in the case of a square pipe, the bolts for clamping and fixing the flange portion of the pipe end and the fastening metal fitting are at the corners of the corners. When placed, it is firmly clamped. However, in the case of a circular pipe such as the screw pile as described above, there is no corner. It became clear that it could not be clamped and fastened.

  In view of such circumstances, the present applicant is superior in terms of workability and in terms of fastening strength, particularly in terms of torsional strength at the fastening surface (contact surface) required for the pile. A pile fastening structure and a fastener used for the pile fastening structure that are excellent in terms of shear strength at the contact surface and also in economical efficiency have been provided (see Patent Document 1).

  The pile fastening structure and the fastener are suitable as a fastener when the pipe constituting the above-described pile is circular, and can also be used as a fastener for a circular pipe other than the pile.

In this specification, the fastening bracket and the fitting to be fastened are expressed as "... brackets" for convenience, but the material is not limited to those made of metal, and cement, plastic or Used in a wide range of concepts, including those of other materials such as ceramics.
JP 2002-194735 A

  By the way, as described above, the pile fastening structure and the fastener have excellent operational effects as compared with those before that.

  However, when the pile is to be screwed into the soil, depending on the ground conditions, the engagement portion between the concave portion and the convex portion formed on the contact surface of the fastener to be fastened may cause an impact during rotation. In rare cases, however, it may not be tolerated.

  The present invention has been made in view of such a situation, and an object thereof is to provide a pile fastening structure and a fastener that can cope with a large rotational torque and impact during rotation.

The above problem can be solved by the pile fastening structure according to the first invention. That means
The pile fastening structure according to the first aspect of the present invention is a taper that protrudes inward at the fastening end portion that faces and abuts, and the surface on the side away from the abutment surface that is the end surface is thin on the inner peripheral end side. For fastening to be integrally formed at each fastening end portion facing each other between two circular pipes to be fastened having a flange portion formed in a shape at the fastening end portion and constituting a pile for buried in soil Metal fittings,
The inner surface of the concave portion having a U-shaped cross section has a tapered surface corresponding to the taper of the flange portion of the fitting to be fastened, and the two fastening fittings are opposed to each other and brought into contact with each other. Fastening fittings that sandwich the flange portions with the U-shaped recesses in the
A bolt that clamps and fixes the abutting flange portion with a U-shaped concave portion of the fastening metal fitting in a state in which the flange portions of the two to-be-fastened metal fittings face each other and are in contact with each other;
The bolt is disposed so as to penetrate the contact surface of the fastened metal fitting in the radial direction of the corresponding contact surface, and the fastening metal fitting is attracted to the fastened metal fitting side by the bolt, so that two fastened metal fittings are obtained. A pile fastening structure configured to clamp and fix the flange portion of
A concave portion is formed on each of the contact surfaces of each of the fittings to be fastened / abutted so as to form an integral space in a state of being opposed / abutted,
At the time of fastening, an engagement body having a shape substantially corresponding to the space is disposed in the recess, and the pair of fastening hardware is fastened by the fastening hardware and the bolt.

  Thus, according to the pile fastening structure according to the first invention (the invention described in claim 1), the two pipes constituting the pile or a part of the pile according to the configuration described as the premise of the present invention. If the abutment surfaces of the respective fastening fittings formed integrally with the end of the flange are brought into contact with each other, the tapered surfaces of the flange portions of these two fastening fittings are on the outside. Both tapered inner protrusions are formed, and the U-shaped recesses of the fastening metal fittings each having a tapered surface are fitted into the protrusions. Then, in this state, if the bolt is penetrated in the radial direction and the fastening metal fitting and the fastening metal fitting are sandwiched, the fastening to the both tapered protrusions formed by the flange portion of the fastening metal fitting is performed. Fitting of the concave part with the taper surface of the metal fitting by the strong “wedge action” is completed, and as a result, the fitting parts to be fastened are firmly fastened by the fastening metal fitting, and the pile or part of the pile It is possible to firmly fasten the two pipes forming the pipe, and it is possible to provide an excellent pile fastening structure having a high earthquake resistance and a bending strength and a shear strength equal to or higher than those of the pipe.

  Further, in addition to such an operational effect, as described above, as an operational effect peculiar to the present invention, as described above, the engaging body is disposed in an integral space formed by the recesses formed on the contact surfaces of the two fastening fittings. By doing so, a large stress (rotational torque) can be transmitted in the rotational direction between the two fasteners to be fastened via the engagement body. In addition, in this case, since the engaging body is constituted by a member different from the fitting for fastening, the engaging body on which a large shearing force or the like acts due to the rotational torque is adapted to the use conditions. If it is made of a material having a high permissible shear stress as appropriate, it can be used without any problem even under severe conditions in accordance with the conditions.

In the pile fastening structure according to the first aspect of the invention, the concave portion is a cylindrical concave portion, and the engaging body is a columnar body having a height twice that of the concave portion, due to the rotational torque acting on the pile fastening structure. The compressive force acts on the contact surface of the engaging body and the recess that contacts it, and the distribution state of this stress (compression stress) on the contact surface is largely at the outer side of the wall thickness of the fitting to be fastened. Or since it becomes small as it goes to the inner surface direction, the situation where the to-be-fastened metal fitting is damaged can be avoided. In addition, the contact area between the engaging body and the abutting surface of the recess that contacts the engaging body can be made as large as possible, and the acting stress distribution changes smoothly. Therefore, it is possible to avoid a situation where the fastening hardware is damaged.
Further, in the case of the above configuration, since the recess and the engagement body are both circularly machined, it is easy to perform machining, and it is possible to reduce the dimensional difference between the recess (the space) and the engagement body. In some cases, the structure is stronger due to the impact force generated at the beginning of rotation.

  In the pile fastening structure according to the first invention, the wall portion (inner peripheral wall portion) forming the recess is discontinuous between the outer peripheral portion and the inner peripheral portion of the fastener to be fastened, and the engaging body is the fastener to be fastened. If part of the outer peripheral surface and the inner peripheral surface are exposed, the state in which the engaging body is disposed can be visually confirmed even after the coupling is completed. Further, when the recess is a cylindrical recess and the engagement body is a columnar body, the area of the contact surface of the engagement body can be further increased, and the area of the contact surface of the corresponding fastened fitting is also Rather than being determined by the thickness of the metal fitting to be fastened, it becomes a cylindrical partial cylindrical surface of the inner peripheral wall of the recess that has a larger dimension, and therefore it is possible to reduce the compressive stress or shear stress per unit area. Become. In addition, the state of change in the stress distribution on the cylindrical contact surface can be made smoother.

  In the pile fastening structure according to the first aspect of the present invention, when at least one pair of the recesses is provided to face the virtual center of the contact surface of the fastener to be fastened, This is a preferable configuration in that it can receive stress evenly. Needless to say, two pairs or more may be provided instead of one pair as necessary.

Moreover, in order to solve the said subject, the fastener concerning this 2nd invention has comprised the following structures. That means
The fastener according to the second aspect of the present invention has a tapered shape that protrudes inward at the fastening end portion that faces and abuts, and the surface on the side away from the abutment surface that is the end surface is thin on the inner peripheral end side. Fastening fittings integrally formed at the fastening end portions facing each other between the two circular pipes to be fastened, which have a flange portion formed on the fastening end portion and constitute the pile for buried in the soil When,
The inner surface of the concave portion having a U-shaped cross section has a tapered surface corresponding to the taper of the flange portion of the fitting to be fastened, and the two fastening fittings are opposed to each other and brought into contact with each other. Fastening fittings that sandwich the flange portions with the U-shaped recesses in the
A bolt that clamps and fixes the abutting flange portion with a U-shaped recess of the fastening metal fitting in a state in which the flange portions of the two to-be-fastened metal fittings face each other and are in contact with each other;
The bolt is disposed so as to penetrate the contact surface of the fastened metal fitting in the radial direction of the corresponding contact surface, and the fastening metal fitting is attracted to the fastened metal fitting side by the bolt, and two fastened metal fittings are obtained. A fastener configured to clamp and fix the flange portion of
A concave portion is formed on the respective abutting surfaces of each of the fittings to be abutted and abutted so as to form an integral space in a state of facing and abutting,
At the time of fastening, an engagement body having a shape substantially corresponding to the space is disposed in the recess, and the pair of fastening hardware is fastened by the fastening hardware and the bolt.

Thus, according to the pile fastening structure according to the second invention (invention of claim 5), when the two fasteners to be fastened are brought into contact with each other by the configuration described as the premise of the invention, Both tapered inner protrusions are formed with the tapered surfaces of the flange portions of the two fasteners to be outward facing, and these protrusions are formed on the outer surface of the fastening brackets having tapered surfaces. It is generally fitted by a shaped recess. Then, if the fastening fitting and the fastening fitting are screwed by placing bolts in the through-holes formed in the abutting contact surface from this generally fitted state, Completion and the fastening hardware to be opposed to each other are firmly fastened by a “wedge action” by the fastening hardware. Moreover, since the bolt is disposed on the contact surface, the fastening portion of the pipe has shear strength and torsional strength that are higher than those of the pipe to be fastened. As a result, for example, it is possible to effectively transmit the rotational torque acting at the time of construction in the pile screwing method to the pile tip of the underground part.
In particular, due to the configuration unique to the second invention, as in the first invention, as described above, the engaging body is provided in an integral space formed by the recesses formed in the contact surfaces of the two fastening fittings. By arrange | positioning, a big stress (rotational torque) can be transmitted between two to-be-fastened metal fittings in a rotation direction via this engaging body. In addition, in this case, since the engaging body is constituted by a member different from the fitting for fastening, the engaging body on which a large shearing force or the like acts due to the rotational torque is adapted to the use conditions. If it is made of a material having a high permissible shear stress as appropriate, it can be used without any problem even under severe conditions in accordance with the conditions.
This fastener is a fastener suitable for the first invention.

In the pile fastening structure according to the second aspect of the invention, the concave portion is a cylindrical concave portion, and the engaging body is a columnar body having a height approximately twice that of the concave portion, the rotational torque acting on the pile fastening structure. The compressive force acts on the abutment surface of the engaging body and the concave portion that contacts the engaging body. The distribution state of this stress (compression stress) on the abutment surface is greatly increased in the central portion of the thickness of the metal fitting for fastening. Therefore, it is possible to avoid a situation in which the fastener to be fastened is damaged. In addition, the contact area between the engaging body and the abutting surface of the recess that contacts the engaging body can be made as large as possible, and the acting stress distribution changes smoothly. Therefore, it is possible to avoid a situation where the fastening hardware is damaged.
Further, in the case of the above configuration, since the concave portion and the engaging body are both circularly processed, machining can be performed using a rotary tool, so that it is easy to do, and the concave portion (the space) and the engaging body The dimensional difference (dimensional accuracy) can be further reduced, and in such a case, the structure is stronger against the impact force generated at the beginning of rotation.

  In the pile fastening structure according to the second invention, a through hole having a circular cross section is formed in the contact portion between the contact surfaces of the pair of fasteners facing each other in a state where the corresponding contact surfaces are in contact with each other. Preferably, a groove having a semicircular cross section is formed in each contact surface in the radial direction, and a hole having a circular cross section corresponding to the through hole is formed in the fastening bracket. As a configuration in which the taper surface is inserted between the metal fittings and a taper surface is used (a wedge action is used), the taper surfaces of the two upper and lower metal fittings to be fastened are preferably tightened evenly.

  Thus, according to the pile fastening structure according to the first invention and the fastener according to the second invention configured as described above, the pile that can cope with transmission of a large rotational torque, impact and the like during rotation. Fastening structures and fasteners can be provided.

[Example 1]
Hereinafter, a pile fastening structure according to an embodiment of the present invention and a fastener used in the structure will be specifically described with reference to the drawings.

  1 is a plan view showing the configuration of a fastener of a pile fastening structure according to one embodiment of the present invention, FIG. 2 is a side view from the direction of arrows II-II in FIG. 1, and FIG. FIG. 4 is a cross-sectional view taken along the line III-III in FIG. 1 showing the configuration of the recess and the engaging body that transmit the rotational torque in the fastening structure shown in FIG. FIG. 2 is a partial plan view of a contact surface of the fastener to be fastened shown in FIG. 1.

  1, 2, or 3, 1 is a fastening metal fitting, 2 is a fastening metal fitting, 3 is a headed bolt for screwing the fastening metal fitting 1 and the fastening metal fitting 2, and 4 is a bolt 3. A nut to be screwed, A is one circular pipe to be fastened (circular steel pipe for pile), and B is another circular pipe to be fastened (circular steel pipe for pile).

  As shown in FIGS. 2 and 3, the fitting 2 to be fastened is welded in advance at the end of one circular pipe A to be fastened at a factory or the like (reference numeral “10” in FIGS. 2 and 3). (Refer to the part of ")". Further, the fastening fitting 2 having the same physical structure as the fastening fitting 2 is welded to the end portion on the fastening side of the other circular pipe B to be fastened (reference numerals in FIGS. 2 and 3). (Refer to “10”). Then, the fastening end portions of the two circular pipes A and B arranged so that the fastening end portions in the longitudinal direction face each other are opposed to each other. By being clamped and fixed by the metal fitting 1, both pipes are firmly fastened.

  As shown in FIG. 3 in a side sectional view, the metal fitting for fastening 2 has a size in which the outer periphery coincides with the outer periphery of a circular pipe A or a circular pipe B as shown in FIG. As shown in FIG. 3, a flange portion 2a is provided around the inner periphery of the end portion to be fastened, and the flange portion 2a is in contact with the flange portion 2a. The surface 2c on the side away from the surface 2b is formed in a tapered shape that gradually becomes thinner on the inner peripheral end 2d side. The contact surface 2b is a plane orthogonal to the longitudinal direction (direction to be connected) of the circular pipe A or the circular pipe B. The contact surface 2b has a radial dimension from the ring-shaped center (virtual center O2 of the contact surface) in the radial direction when viewed from above, and is substantially equal in dimension to the cross section of the bolt 3. A plurality of grooves 2f (see FIG. 1 and FIG. 5) having a semicircular cross section (exactly slightly larger) are formed (in this embodiment, four locations are equally distributed).

Moreover, in the case of the to-be-fastened metal fitting 2 according to this embodiment, as shown in FIG. 1, with respect to the virtual center O2 among the four places between the groove 2f and the groove 2f of the contact surface 2b. In other words, two concave portions 2k that are circular and three-dimensionally cylindrical in plan view are formed at two opposite positions, that is, at an interval of 180 degrees. Since the dimension D2 of the cylindrical diameter of the recess 2k is larger than the thickness of the metal fitting 2 to be fastened, the outer peripheral wall surface and the inner peripheral wall surface of the recess 2k are discontinuous, that is, the circumference The wall portion of the recess 2k is partially cut away in the direction to form an opening 2j (see FIGS. 2 to 5).
The cylindrical recesses 2k are in contact with the contact surfaces 2b of the two fasteners 2 to be fastened, and the recesses 2k of the contact surfaces 2b form one cylindrical space G. . Then, when the two fasteners 2 to be fastened are fastened to the cylindrical space G, a circle having a size substantially matching the space G, precisely a size slightly smaller than the space G, Columnar engaging bodies F are respectively arranged.

  By the way, although the said recessed part 2k is formed in two places for every 180 degree | times on each contact surface 2b, you may form four places every 90 degree | times, In such a case, the said engaging body F is also the recessed part. Four are arranged in accordance with the number of 2k (space G).

Further, as shown in FIG. 1, the fastening metal fitting 1 has a thick wall with a partial arc on the outer peripheral surface that substantially matches the shape of the inner peripheral surface of the metal fitting 2 to be fastened. As shown in FIG. 3, it has a partial cylindrical ring shape, and as shown in FIG. Have. The inner surfaces 1d and 1e facing each other of the recess 1A are constituted by tapered surfaces having a taper angle equal to the taper angle of the tapered surface 2c of the fitting 2 to be fastened. That is, as shown in FIG. 3, the concave portion 1A is formed in the state in which the two fasteners 2 to be fastened are brought into contact with each other at the contact surfaces 2b (see FIG. 3). The size of the projection C is such that the both taper-shaped projections C composed of the two flange portions 2a are sandwiched, and therefore the depth dimension of the recess 1A is clamped in the clamped state (in FIG. 3). The dimension is slightly larger than the dimension of the protrusion C in the left-right direction), so that a so-called “furrow” M (see FIG. 3) is formed.
Further, in a state before the fastening metal fitting 1 is clamped to the fastening metal fitting 2 by the bolt 3, the curvature radius R1 of the outer peripheral surface of the fastening metal fitting 1 is shown in FIG. As described above, it is slightly larger than the radius of curvature R2 of the inner peripheral surface of the flange portion 2a of the metal fitting 2 to be fastened, that is, in a state where the metal fitting 1 for fastening is tightly sandwiched with the metal fitting 2 to be fastened. The concave portion 1A is configured to have a dimension that overlaps the corresponding tapered surface 2c in the radial direction.
Further, as shown in FIG. 3, a through hole 1H for inserting the bolt 3 is formed at the center position in the circumferential direction of the fastening bracket 1 and in the center position in the vertical direction. A flat portion 1L is formed around the through hole 1H of the inner peripheral surface 1B of the fastening bracket 1 so that the contact surface 3E of the head 3h of the bolt 3 shown in FIG. Yes.

  And in the case of a present Example, the said fastening metal fitting 1 and the to-be-fastened metal fitting 2 are the products made from the castings (metal) which can be welded, and were manufactured by casting. However, the fastening metal fitting 1 and the fastening metal fitting 2 may be forged products or manufactured by machining.

  In this embodiment, the engagement body F is made of general carbon steel having a high mechanical strength in terms of material, but is not limited to this. For example, the engagement body F may be tool steel. Alternatively, it may be stainless steel or other alloys.

  Thus, the fastening metal fitting 1 and the fastening metal fitting 2 configured as described above can be fixed to the end surfaces of the circular pipes A and B to be fastened in advance by welding at a factory or the like. It can be concluded as follows. That is, first, as shown in FIG. 1, the fastening bracket 1 is formed on the flange portion 2a of the fastening fitting 2 fixed to the end surface of one circular pipe B, as shown in FIG. A plurality, four in this embodiment, are lightly temporarily fixed with bolts 3 and nuts 4. That is, the fastening metal fitting 1 is temporarily fixed to the fastening metal fitting 2 so as to be movable toward the inner diameter side. Further, the engaging body F is disposed in the concave portion 1A of the contact surface 2b.

  In this state, the contact surface 2b of the metal fitting 2 to be fastened of the circular pipe B is set to the contact surface 2b of the metal fitting 2 to be fastened of the circular pipe A, and the engaging body F is set to the concave portion 1A of the circular pipe B. It abuts so that it may be inserted.

  At this time, since the fastening metal fitting 1 is temporarily fixed to the fastening metal fitting 2 and can be moved as described above, the two metal fittings for the circular pipe B are prevented from interfering with the fastener 1. The contact surface 2b of the fastening metal fitting 2 is brought into contact. Next, when the nut 4 is tightened in a state in which the contact surfaces 2b of the two circular pipes A and B are in contact with each other, as shown in FIG. 2 or FIG. 1A is sandwiched between both tapered projections C formed by the flange portions 2a of the two clamped metal fittings 2 that come into contact with each other. As a result, the "fastening action" by the taper surface causes the fastening metal fitting 1 As a result, the two fasteners 2 to be fastened are firmly fastened. In FIGS. 1 and 2, 5 is a flat washer.

  And in the fastening part fastened in this way, since the bolt 3 penetrates the two contact surfaces 2b as described above, due to the transmission of the rotational torque to this contact surface 2b, When a torsional stress and a shearing force are applied, the bolt 3 and the groove 2f portion in contact with the bolt 3 also act.

In the case of the embodiment according to the present invention, the torsional stress and shearing force also act between the engagement body F and the inner peripheral surface of the recess 2k, so that a large torsional resistance and shearing force are obtained. It will be.
As described above, due to the rotational torque acting between the engagement body F and the inner peripheral surface of the recess 2k, a compressive force acts on the contact surface of the engagement body F and the recess 2k that contacts it. The distribution state of the stress (compressive stress) on the contact surface is large at the central portion of the wall thickness of the metal fitting 2 to be fastened and decreases toward the outer surface or the inner surface, so that the metal fitting 2 to be fastened is damaged. A situation can be avoided. In addition, the contact area between the engagement body F and the contact surface of the recess 2k that contacts the engaging member F can be made as large as possible as compared with the conventional case where the surface for transmitting the compressive force is flat. Since the stress distribution to be smoothly changed, a large rotational torque can be transmitted.

 Further, since the recess 2k and the engagement body F are both circularly machined, it is easy to perform machining. Therefore, the dimensional difference (accuracy) between the recess 2k (the space G) and the engagement body F is further reduced. In such a case, the structure is stronger due to the impact force generated at the beginning of rotation. In addition, since it is cylindrical processing, it is possible to easily perform processing with a general-purpose processing tool at low cost.

In addition, when the fastening of the two metal fittings 2 to be fastened by the fastening metal fittings 1 and the bolts 3 or in the process of the fastening, as described above, the above-described arrangement of the two metal fittings 2 is arranged from the opening 2j on the outer periphery of the recess 2k. The engaging body F can be visually recognized.
Therefore, even if the engagement body F is forgotten to be disposed in the recess 2k (space G), it can be easily checked.

  As described above, according to the pile fastening structure according to the embodiment of the present invention, it is excellent in terms of workability, in terms of fastening strength, particularly in terms of torsional strength on the contact surface, and in terms of shear strength. In addition, it is possible to realize a pile fastening structure that is excellent in terms of economy.

  Moreover, according to the fastener concerning this invention, it becomes an optimal fastener for the said pile fastening structure, and it becomes a fastener with which an unnecessary precision is not requested | required inexpensively and fastening work is easy.

  The pile fastening structure according to the present invention and the fastener used in the fastening structure can be used for fastening a pile driven in order to strengthen the ground at a construction site or a civil engineering site.

It is a top view which shows the structure of the part of the fastener of the pile fastening structure concerning 1 Example of this invention. It is a side view from the II-II arrow direction of FIG. FIG. 3 is a cross-sectional view taken along the line III-III in FIG. 1 showing a configuration of a recess and a portion of an engaging body that transmit rotational torque in the fastening structure shown in FIGS. 1 and 2. FIG. 3 is a partially enlarged side view of a portion indicated by a one-dot chain line in FIG. 2. It is a partial top view of the contact surface of the to-be-fastened metal fitting shown in FIG.

Explanation of symbols

1 ... Fastening bracket
1A ... Recess
1d, 1e ... inside
2 ... Fastening bracket
2a… Flange part
2b… Abutting surface
2k ... recess
3 ... Bolt A, B ... Round pipe
F: Engagement body
G ... space

Claims (7)

A flange portion formed in a taper shape with a surface projecting inward at a fastening end portion that faces and abuts, and a surface on a side away from a contact surface that is an end surface is thinned on an inner peripheral end side is the fastening end portion A fastening hardware integrally formed at each fastening end facing each other between the two circular pipes to be fastened that constitute the pile for burying in the soil,
The inner surface of the concave portion having a U-shaped cross section has a tapered surface corresponding to the taper of the flange portion of the fitting to be fastened, and the two fastening fittings are opposed to each other and brought into contact with each other. Fastening fittings that sandwich the flange portions with the U-shaped recesses in the
A bolt that clamps and fixes the abutting flange portion with a U-shaped recess of the fastening metal fitting in a state in which the flange portions of the two to-be-fastened metal fittings face each other and are in contact with each other;
The bolt is disposed so as to penetrate the contact surface of the fastened metal fitting in the radial direction of the corresponding contact surface, and the fastening metal fitting is attracted to the fastened metal fitting side by the bolt, and two fastened metal fittings are obtained. A pile fastening structure configured to sandwich and fix the flange portion of
A concave portion is formed on the respective abutting surfaces of each of the fittings to be abutted and abutted so as to form an integral space in a state of facing and abutting,
A pile having a configuration in which an engaging body having a shape substantially corresponding to the space is disposed in the recess when fastening, and the pair of fastening hardware is fastened by the fastening hardware and the bolt. tightening structure.   The pile fastening structure according to claim 1, wherein the concave portion is a cylindrical concave portion, and the engaging body is a columnar body having a height twice that of the concave portion.   The wall portion forming the recess is discontinuous between the outer peripheral portion and the inner peripheral portion of the fastener to be fastened, and the engaging body is partially exposed on the outer peripheral surface and the inner peripheral surface of the fastener to be fastened. The pile fastening structure according to claim 1 or 2, characterized in that.   The pile fastening structure according to any one of claims 1 to 3, wherein at least one pair of the recesses is provided against the center of the abutting surface of the fastener to be fastened. A flange portion formed in a taper shape with a surface projecting inward at a fastening end portion that faces and abuts, and a surface on a side away from a contact surface that is an end surface is thinned on an inner peripheral end side is the fastening end portion A fastening hardware integrally formed at each fastening end facing each other between the two circular pipes to be fastened that constitute the pile for burying in the soil,
The inner surface of the concave portion having a U-shaped cross section has a tapered surface corresponding to the taper of the flange portion of the fitting to be fastened, and the two fastening fittings are opposed to each other and brought into contact with each other. Fastening fittings that sandwich the flange portions with the U-shaped recesses in the
A bolt that clamps and fixes the abutting flange portion with a U-shaped recess of the fastening metal fitting in a state in which the flange portions of the two to-be-fastened metal fittings face each other and are in contact with each other;
The bolt is disposed so as to penetrate the contact surface of the fastened metal fitting in the radial direction of the corresponding contact surface, and the fastening metal fitting is attracted to the fastened metal fitting side by the bolt, and two fastened metal fittings are obtained. A fastener configured to clamp and fix the flange portion of
A concave portion is formed on the respective abutting surfaces of each of the fittings to be abutted and abutted so as to form an integral space in a state of facing and abutting,
When fastening, an engagement body having a shape substantially corresponding to the space is disposed in the recess, and the pair of fasteners to be fastened is fastened by the fastening bracket and the bolt. Ingredients.   The fastener according to claim 5, wherein the recess is a cylindrical recess, and the engagement body is a cylindrical body having a height approximately twice that of the recess. Between the contact surfaces of the pair of fasteners facing each other, a cross-sectional semicircle is formed on each contact surface so that a through hole having a circular cross section is formed in the contact portion in a state where the corresponding contact surfaces are in contact with each other. The fastener according to claim 5 or 6, wherein a groove having a shape is formed in a radial direction, and a hole having a circular cross section corresponding to the through hole is formed in the fastener.

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