JP3338387B2 - Joint of foundation pile - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to the joint portion of the foundation pile in the case of a pile of a plurality book shirttail vertically interest (hereinafter simply
This is referred to as the “pile joint”. ) .

[0002]

2. Description of the Related Art A connection portion of an existing pile is formed by welding end plates fixed to a pile end portion, by forming a screw portion at a pile end portion and joining by screw type, or by using a ring-shaped metal fitting. There are things to join.

[0003] For example, Japanese Unexamined Utility Model Publication No. 50-12512 and Japanese Unexamined Utility Model Application Publication No.
No. 730 describes a reinforcing band or a joint ring having irregularities arranged so as to straddle between upper and lower pile ends, and tightening these to integrate the upper and lower piles.

Further, Japanese Utility Model Publication No. 7-47453 discloses that
It describes that a relatively narrow connection ring having several annular grooves is pressed against a pile joint with a fastener and integrated by welding.

[0005] In the case where a knotted pile or the like is constructed as an embedded pile, the excavation hole is filled with a hardening filler such as soil mortar or cement milk, and the pile is set therein.
The foundation pile with large peripheral bearing capacity is formed by the hardening of the hardening filler.

[0006]

The method of welding the end plates is a butt welding, which requires high-precision construction on site. In the case of small-diameter piles, special skill is required, which is troublesome. This increases costs.

Further, the conventional ring-shaped joint fitting is mainly press-fitted to the end of the pile, and the joint fitting itself is integrated with the upper and lower piles. However, it is necessary to process the end of the pile. , A lot of processing time. In particular, processing on the pile side leads to an increase in the cost of the pile itself.

In addition, it takes time and effort to perform the joining work on site, and since it is assumed that the pile is integrated with the pile body by tightening or the like, the joint may not function properly if not sufficiently tightened. In addition, it is conceivable that the fitting fitting, the fastening tool, and the like protruding from the outer peripheral surface of the pile may be an obstacle depending on a mounting method.

On the other hand, a large compressive force acts on the foundation pile by supporting the upper structure, and when only the compressive force in the axial direction is considered, the transmission of the compressive force mainly between the upper and lower pile end faces is ensured. It is only necessary to integrate them.

The present invention has been made to solve the above-mentioned problems in the prior art, and does not require any special processing, is easy to perform on-site joining work, and has a structurally reasonable pile. The purpose of the present invention is to provide a joint part.

[0011]

According to a first aspect of the present invention, a joint portion of a pile has an inner diameter substantially equal to an outer diameter of the pile, and a required section of an end of a lower pile whose end faces abut each other and an upper section of the upper pile. The end of the pile has a length that covers the required section, and a metal connection pipe with a large number of irregularities formed on the inner surface is placed between the upper and lower pile ends,
It is characterized in that at least one of the upper and lower ends of the pile is relatively movable in the pile axis direction in the connection pipe against vibration or pulling force acting on the pile.

In other words, the pile support force between the upper and lower piles to be connected is basically transmitted directly between the upper and lower pile end faces, instead of integrating the pile end and the connection pipe by fixing. .

However, it is necessary to prevent the connection pipe from easily coming off from the end of the pile, and it is desirable that the connection pipe be easily fixed to a degree of temporary fixing or not completely restrained. Note that a simple stopper may be provided at the lower pile end or the connection pipe side, and the connection pipe may be supported by the stopper.

The irregularities of the connecting pipe can be provided not only on the inner surface but also on the outer surface. Claim 2 relates to the joint portion of the pile according to claim 1, wherein the connection pipe is fixed to one of the upper and lower pile ends with a bolt or a pin penetrating the pipe wall of the connection pipe. is there.

Pile is mainly made of precast concrete,
A steel pipe pile, a steel-concrete composite pile, and the like are targeted. As the connection pipe, a short-length steel pipe with an inner projection can be used, but the material is not necessarily limited.

As the steel pipe with an inner surface projection, a steel tube having a spiral projection on its inner surface is known, and in addition, there is a steel tube having a number of small projections formed on the inner surface or the outer surface of the steel tube. Of course, it may be one in which irregularities such as protrusions are formed not only on the inner surface but also on the outer surface.

In the present application, when the connecting pipe has substantially the same inner diameter as the outer diameter of the pile, the inner diameter refers to the inner diameter including the projection. As described above, the pile supporting force between the upper and lower piles is basically transmitted directly between the upper and lower pile end faces, and the upper and lower piles can be relatively moved in the pile axial direction within the connection pipe, so that the connection pipe, The pile does not require so large tensile strength and bending strength, and has a reasonable structure.

However, the horizontal displacement of the pile at the joint is not completely free, and a metal connection pipe having a large number of irregularities on the inner surface is used as the connection pipe, so that a straight connection without irregularities can be achieved. Compared to a tube,
The shear rigidity of the joint increases, and the required bending strength can be improved according to the position of the joint.

According to a third aspect of the present invention, a plate-like or projecting stopper is provided on the inner surface of the intermediate portion of the connecting pipe, and the case where the stopper is in contact with the end faces of the upper and lower piles is limited. With the stopper, the stopper has a positioning function, and it is possible to prevent the connection pipe from being moved carelessly. In addition, even if the clearance is large due to the relationship between the outer diameter of the pile and the inner diameter of the connection pipe, it can be dealt with.

In addition, the connecting pipe may be fixed to the end of the lower pile in advance by welding or an adhesive so that only the upper pile can be slightly moved in the connecting pipe. Claim 4 is a case where at least the lower pile to be connected is a knot pile having a knot portion and a torso portion alternately, and the connecting pipe is externally fitted to a torso portion formed at an end portion of the knot pile. .

In this case, the joints of the lower knots serve as stoppers, fulfill the function of positioning the connecting pipe, and can prevent the connecting pipe from falling down. The joint part of the pile according to claim 5 of the present application is a joint part of a lower pile composed of a knotted pile constructed in an excavation hole as an embedded pile and an upper pile having at least a lower end having a circular cross-sectional shape, At the outer periphery of the joint end of the upper and lower piles, a metal connection pipe with a large number of irregularities formed on the inner surface with an inner diameter slightly larger than the outer diameter of the trunk of the knot pile as a lower pile, the upper torso of the lower pile And the upper pile is installed so as to cover the lower end of the upper pile, and the upper and lower piles are joined by hardening of the hardening filler filled in the excavation hole.

As described above, approximately, the outer diameter of the node> the diameter of the connection pipe>
The connection pipe is installed between the top node of the lower pile and the bottom of the upper pile under the relation of the outer diameter of the trunk, and the hardening filler that solidifies the pile circumference is also introduced inside the connection pipe. In this way, the upper and lower piles are joined.

When the inner diameter of the connecting pipe is slightly larger than the outer diameter of the pile, the state is close to the engaged state, and the upper and lower piles and the connecting pipe are joined by the hardening of the hardening filler material around the joint. .

When the connecting pipe is installed, the joining work using the connecting pipe can be performed smoothly by temporarily attaching the joining ends of the upper and lower piles with an adhesive. Further, the adhesive strength of the adhesive can be added as the bonding strength. In addition, as a method of temporary attachment, not only an adhesive but also various methods such as winding an adhesive tape are conceivable.

At this time, since the connection pipe has a large number of irregularities formed on the inner surface, the connection pipe has a higher shear strength than a case where there is no irregularity, and also has excellent adhesion performance with the curable filler. In this sense, it is desirable that the inner surface of the connection pipe has irregularities, but the irregularities may be formed on both the inner and outer surfaces.

In the inventions according to claims 1 to 4, the upper and lower pile ends are not directly joined to each other, whereas in the invention according to claim 5, the upper and lower pile ends are solidified by the hardening filler. Parts are joined via connecting pipes, but it does not take much time and labor like the joints by conventional welding etc. Also, the conventional ring-shaped joint fitting is crimped to the pile end and integrated It does not cause the pile to be damaged as in the case.

The embedding pile is basically provided by embedding a ready-made pile into the ground excavated to a depth substantially equal to the entire length thereof, and a hardening filler (soil mortar) mixed with excavated soil at the time of excavation. Etc.), or the lower pile is submerged in a single hardening filler such as cement milk, and the upper pile is connected and further submerged. In some cases, it is conceivable that the lower pile and the upper pile are connected in advance and then laid.

The joint part of the pile according to claim 6 of the present application is a joint part of a lower pile composed of a knotted pile constructed as an embedded pile in an excavation hole and an upper pile having at least a lower end having a circular cross section. There is a metal connection in which a large number of irregularities are formed on the inner surface having an inner diameter larger than the outer diameter of the trunk of the knotted pile as the lower pile and smaller than the outer diameter of the knotted part on the outer periphery of the joint end of the upper and lower piles The pipe is installed so as to cover the upper torso of the lower pile and the lower end of the upper pile, and a spacer is interposed between the inner surface of the connection pipe and the joint end of the upper and lower piles, so that the hardening The filler is infiltrated between the joint ends of the upper and lower piles held by the spacer and the connecting pipe, and the upper and lower piles are joined by hardening of the hardening filler inside and outside the connecting pipe. is there.

Claim 6 is the case where the difference between the inner diameter of the connecting pipe and the outer diameter of the pile is large, and the amount of the hardening filler entering the inside of the connecting pipe is large as compared with the case of claim 5. In this case, the adhesion effect due to the unevenness formed on the inner surface of the connection pipe increases.

In this case, the connection pipe can be held at a predetermined position by interposing a spacer between the connection ends of the upper and lower piles and the connection pipe. As a spacer,
A plurality of wedge-shaped jigs that are driven between the joint end of the pile and the inner surface of the connection pipe, protrusions that protrude more than the outer surface of the joint end of the pile or the inner surface of the connection pipe. A large number of screws), a plurality of threaded guide pins penetrating through the pipe wall of the connection pipe, and the amount of penetration into the inside can be adjusted in a threaded manner by utilizing the shape memory characteristics of a shape memory alloy. Spacers and the like used as wedges are conceivable.

[0031]

FIG. 1 shows an embodiment of a joint portion of a pile according to the first aspect of the present invention. A lower pile 1a and an upper pile 1b are formed with a large number of irregularities on the inner surface. The connection is made through the connection pipe 2.

In this example, a steel pipe with an inner projection is used as the connecting pipe 2, and the inner diameter at the tip of the inner projection 2 a is substantially the same as the outer diameter of the pile 1. In addition, the connecting pipe 2 has a length h that covers an end required section of the lower pile 1a and an end required section of the upper pile 1b, whose end faces abut each other.

The axial compressive force due to the overload (mainly the load on the upper structure) is transmitted directly from the lower end surface of the upper pile 1b to the upper end surface of the lower pile 1a. Bending resistance is given to horizontal displacement of the upper and lower piles 1a and 1b without bearing the overload.

In this case, the connecting pipe having the projection 2a has a higher bending rigidity than a straight pipe having no projection.
There is an advantage that the shear strength is high. In addition, because of the large number of protrusions 2a, the upper and lower piles 1a and 1b are guided to the center of the connection pipe 2, and the axial compression force due to the mounting load between the connection pipe 2 and the piles 1a and 1b is increased and decreased. It is directly and smoothly transmitted between the pile 1b and the pile 1a.

Further, there is a slight clearance between the outer surfaces of the upper and lower piles 1a and 1b and the tip of the projection 2a of the connection pipe 2, and when connecting the piles 1a and 1b, the connection pipe 2
To the end of the lower pile 1a, or to insert the upper pile 1b into the connecting pipe 2.

In the figure, reference numeral 3 denotes a connection pipe 2 for the lower pile 1a.
Although a protrusion-like stopper for preventing slipping is shown, various means for preventing slipping are conceivable. FIG. 2 shows an embodiment of a joint portion of a pile according to claim 2 of the present application. In this example, as means for preventing sliding down, a bolt 4 penetrating the connecting pipe 2 made of a steel pipe with an inner surface projection is provided, and the connecting pipe 2 is fixed to the lower pile 1a. In this case, especially when the pile is built, the connecting pipe 2
There is an advantage that displacement can be reliably prevented.

FIG. 3 shows an embodiment of a joint portion of a pile according to claim 3 of the present application. In this example, connection pipe 2
There is a partition plate 5 as a stopper at the center of the stake. When the partition plate 5 connects the upper and lower piles 1a and 1b,
Positioning and connection are easy.

FIG. 4 shows an embodiment of a joint portion of a pile according to claim 4 of the present application. This example is a case where the pile 1 is a knotted pile. When connecting the upper and lower knotted piles 1a and 1b via the connecting pipe 2 made of a steel pipe with an inner surface projection, a node 7 having a larger diameter than the connecting pipe 2 serves as a stopper. Function, positioning,
Easy connection.

FIG. 5 shows another embodiment of the joint portion of a pile according to claim 1 of the present application. In this example, a connecting pipe 2 made of a steel pipe with an inner surface projection is previously mounted on the upper part of the lower pile 1a. The structure is such that the upper pile 1b is simply inserted into the connection pipe 2 at the time of on-site joining, with the adhesive 9 being fixed.

FIG. 6 shows still another embodiment of the joint portion of the pile according to claim 1 of the present application, in which an adhesive 7 is applied to the projection 2a over the entire length of the connecting pipe 2 made of a steel pipe with an inner projection.
Is applied to join the upper and lower piles 1a and 1b. However, also in this case, the upper and lower piles 1a and 1b and the connecting pipe 2 are not integrated, but the displacement of the connecting pipe 2 is mainly prevented. When a large tensile force or bending force is applied, the bonding by the adhesive 7 is broken, so that the upper and lower piles 1
a and 1b are relatively movable in the connection pipe 2 in the axial direction of the pile 1.

FIG. 7 shows an embodiment of a joint portion of a pile according to claim 5 of the present application.
The case where a concrete round pile is added as the upper pile 1b to the knotted pile as a (however, the same applies to steel pipe piles, steel-concrete composite piles, and other piles with at least a circular cross section at the lower end) Can be).

In this example, the connection pipe 2 is
The inner diameter at the portion a is the trunk 1 of the knotted pile as the lower pile 1a.
A connecting pipe 2 slightly larger than the outer diameter of a is used. In addition,
The figure shows a case where a steel pipe with an inner surface projection having a spiral projection 2a on the inner surface is used as the connection pipe 2, but a large number of discontinuous small projections 2a are formed as in the case of FIGS. It may be what has been done.

As a typical construction procedure, first, a hardening filler 11 such as soil mortar or cement milk is used.
A knotted pile as the lower pile 1a is sunk to a predetermined depth in the excavation hole 10 filled with.

With the upper end of the lower pile 1a near the opening of the excavation hole 10, the connection pipe 2 is put on the uppermost node 7 of the knot 1 and temporarily fixed with an adhesive or the like as necessary. . As the connecting pipe 2, a steel pipe with an inner projection having a length of several tens of cm to about 1 m or the like whose inner diameter at the protrusion 2 a is slightly larger than the outer diameter of the trunk 1 a of the node pile 1 is used.

Subsequently, a lower end portion of a concrete round pile in this example is inserted into the upper part of the connection pipe 2 as an upper pile 1b. At this time, an adhesive is applied to one or both of the joining ends of the upper and lower piles 1a and 1b, and the upper and lower piles 1a and 1b are applied.
By temporarily attaching a and 1b to each other in the connection pipe 2, workability can be improved.

In this way, with the upper and lower piles 1a, 1b connected, the pile is further sunk to a predetermined depth, and at this time, the hardening filler 11 is inserted into the gap between the connection pipe 2 and the piles 1a, 1b. By flowing in and solidifying the hardening filler 11, the upper and lower piles 1a, 1b and the connection pipe 2 are integrated from inside and outside of the connection pipe 2, and required rigidity is secured.

The procedure of laying and joining is as follows. The connecting pipe 2 is placed above the lower pile 1a laid down partway as described above.
In general, the upper pile 1b is connected, and the upper pile 1b is further laid down to a predetermined depth.
After connecting a and 1b with each other using the connection pipe 2 or an adhesive or the like as necessary, it is also possible to settle down.

FIG. 8 shows an embodiment of a joint portion of a pile according to claim 6 of the present application, in which a guide pin 12 is used as a spacer. In this example, the same node pile as the lower pile 1a is used as the upper pile 1b.

The guide pins 12 are provided in advance at the lower and upper portions of the connecting pipe 2 at two to four places, respectively, penetrating the pipe wall. Thus, the amount of penetration can be adjusted.

When connecting the knots as the lower stake 1a and the upper stake 1b, the uppermost knot of the lower knot in the state in which the guide pin 12 is loosened (the amount of penetration is reduced). The lower pile 1a and the connection pipe 2 are fixed by putting the lower end of the connection pipe 2 on 7 and screwing the guide pin 12 into place. At that time, by adjusting the amount of penetration of each guide pin 12,
The connection pipe 2 can be positioned.

Subsequently, the lower torso 6 of the upper joint pile is inserted into the inside of the connection pipe 2, and the guide pins 12 are similarly screwed to fix the upper and lower piles 1 a and 1 b to the connection pipe 2. At this time, by applying the adhesive 4 to the joining ends of the upper and lower piles 1a and 1b, the joining operation can be performed more smoothly in a state where the node piles are temporarily attached.

In the state where the upper and lower piles 1a and 1b made of knots are connected, submerging as an embedded pile is performed in the drilling hole 10 filled with the hardening filler 11 such as soil mortar or cement milk. Guide pin 1
The hardening filler 11 penetrates into the space in the joint between the knotted pile and the connection pipe 2 with the interposition of the hardening filler 2 and the hardening filler 11
Is hardened, the joining of the upper and lower knots is completed.

Note that a large number of small projections 2 are provided on the inner surface of the connection pipe 2.
a, the bending stiffness of the connecting pipe 2 itself,
In addition to increasing the shear rigidity, the adhesive force with the curable filler 11 also increases.

FIG. 9 shows another embodiment of the joint portion of the pile according to claim 6 of the present application, in which a wedge 6 is used instead of the guide pin 12 of FIG. In this example, as the upper pile 1b, a steel-pipe concrete composite pile (SC pile) is used instead of the nodal pile.

As a construction procedure, first, a knotted pile as the lower pile 1a is sunk to a predetermined depth in an excavation hole 10 filled with a hardening filler 11 such as soil mortar or cement milk.

With the upper end of the lower pile near the opening of the excavation hole 10, the connecting pipe 2 having a large number of small projections 2a on the inner surface is put on the knot 7 at the uppermost part of the knot. The lower pile 1a and the connection pipe 2 are fixed by driving wedges 13 (4 to 6 places) between the upper body 6 and the inner surface of the connection pipe 2.

Subsequently, the lower end of the upper pile 1b is inserted into the upper part of the connection pipe 2. At this time, the upper and lower piles 1a and 1b are temporarily fixed with the adhesive 4 as needed. In this way, with the upper and lower knots 1 connected, it is further sunk to a predetermined depth. At this time, the hardening filler 11 flows into the gap in the connecting pipe 2, and the hardening filler 11 is solidified to integrate the upper and lower piles 1 a and 1 b with the connecting pipe 2, thereby securing necessary rigidity. .

As described above, the upper and lower piles 1a,
It is also possible to settle after connecting 1b with each other using the connecting pipe 2 or the adhesive 4 if necessary.

[0059]

According to the present invention, a cylindrical connecting pipe having irregularities on the inner surface is used for the connecting portion between the piles, so that no special processing is required on both the pile side and the connecting tool side. The on-site joining work simply involves placing a connecting pipe on the pile end,
Alternatively, only the end of the pile is inserted into the connection pipe, and the workability is excellent. Since the structure is simple and the workability at the site is good, the cost can be reduced. Since the upper and lower piles can be moved relative to each other in the pile axis direction within the connection pipe against vibration or pulling force due to an earthquake or the like acting on the pile, the connection pipe only needs to bear substantially only bending force and shear force. Since a connecting pipe having irregularities on the inner surface and, if necessary, on the inner and outer surfaces is used, the bending strength and the shear strength at the connecting pipe portion can be increased. When applied to embedded piles, the presence of the protrusions increases the adhesion to the curable filler.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an embodiment of the invention according to claim 1 of the present application.

FIG. 2 is a sectional view showing an embodiment of the invention according to claim 2 of the present application.

FIG. 3 is a sectional view showing an embodiment of the invention according to claim 3 of the present application.

FIG. 4 is a sectional view showing an embodiment of the invention according to claim 4 of the present application.

FIG. 5 is a cross-sectional view showing another embodiment of the invention according to claim 1 of the present application.

FIG. 6 is a cross-sectional view showing still another embodiment of the invention according to claim 1 of the present application.

FIG. 7 is a sectional view showing an embodiment of the invention according to claim 5 of the present application.

FIG. 8 is a sectional view showing an embodiment of the invention according to claim 6 of the present application.

FIG. 9 is a sectional view showing another embodiment of the invention according to claim 6 of the present application.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Pile, 1a ... Lower pile, 1b ... Upper pile, 2 ... Connection pipe, 2a ... Projection, 3 ... Stopper, 4 ... Bolt , 5 ... Partition plate, 6 ... Body part, 7 ... Joint part, 8 ... end plate, 9 ... adhesive,
10: drilling hole, 11: hardening filler, 12: guide pin, 13: wedge

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-7-158015 (JP, A) JP-A-63-40035 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) E02D 5/24 101-103

Claims (6)

(57) [Claims] An inner diameter substantially equal to an outer diameter of the pile, and having a length covering an end required section of a lower pile and an end required section of an upper pile whose end faces are abutted with each other; A metal connecting pipe with a large number of irregularities formed on the inner surface is placed between the upper and lower pile ends, and at least one of the upper and lower pile ends is in the pile axial direction in the connecting pipe against vibration or pulling force acting on the pile. A joint part of a foundation pile characterized by being relatively movable. 2. The joint portion of a foundation pile according to claim 1, wherein the connection pipe is fixed to one of upper and lower pile ends with a bolt or a pin penetrating a pipe wall of the connection pipe. 3. The joint portion for a foundation pile according to claim 1, wherein a plate-like or projecting stopper is provided on an inner surface of the intermediate portion of the connection pipe, and the stopper comes into contact with end faces of upper and lower piles. 4. The pile according to claim 1, wherein the lower pile is a knot pile having a knot portion and a torso portion alternately, and the connecting pipe is fitted around a torso portion formed at an end portion of the knot pile. Or the joint part of the foundation pile of 3. 5. A joint portion between a lower pile composed of a knotted pile constructed as a buried pile in an excavation hole and an upper pile having at least a lower end having a circular cross-sectional profile, wherein an outer periphery of a joint end of the upper and lower piles is provided. In addition, a metal connection pipe having a large number of irregularities formed on the inner surface having an inner diameter slightly larger than the outer diameter of the trunk of the knotted pile as the lower pile is covered on the upper trunk of the lower pile and the lower end of the upper pile. A joint part for a foundation pile, which is installed in such a manner that the upper and lower piles are joined by the hardening of a hardening filler filled in a borehole. 6. A joint portion between a lower pile composed of a knotted pile constructed as a buried pile in an excavation hole and an upper pile having at least a lower end having a circular cross-sectional outline, and a joint end outer periphery of the upper and lower piles A metal connecting pipe having a large number of irregularities on the inner surface having an inner diameter larger than the outer diameter of the body part of the knotted pile as the lower pile and smaller than the outer diameter of the knotted part, the upper body part of the lower pile and It is installed so as to cover the lower end of the upper pile, a spacer is interposed between the inner surface of the connection pipe and the joint end of the upper and lower piles, and the hardening filler filled in the drill hole is held by the spacer. A joint part for a foundation pile, characterized in that it penetrates between the joint ends of the upper and lower piles and the connecting pipe, and the upper and lower piles are joined by hardening of a hardening filler inside and outside the connecting pipe.