KR20140001554A

KR20140001554A - Steel pipe joint structures of rotary pile and pile construction method using the same

Info

Publication number: KR20140001554A
Application number: KR1020120069423A
Authority: KR
Inventors: 문형록; 이광신
Original assignee: 반석기초이앤씨(주)
Priority date: 2012-06-27
Filing date: 2012-06-27
Publication date: 2014-01-07

Abstract

The present invention provides a steel pipe connection structure of the rotary pile and a pile construction method using the same, so that there is no obstacle protruding into the connection portion of the adjacent steel pipe in the longitudinal direction to free the intake and take-out of the mechanism required for grouting filling. The steel pipe connection structure of the rotary pile according to a preferred embodiment of the present invention is a rotary file including a plurality of steel pipes having one or more spiral wings in the same outer diameter and outer circumferential surface thereof and being interconnected in a lengthwise direction along the penetration depth to penetrate into the strata. The steel pipes adjacent to each other are characterized in that they have at least one pair of attached metal plates whose ends are overlapped with each other on the outer peripheral surface near the joint surface side, and are welded to the entire joint surface after the cross sections are butted together.

Description

Steel pipe joint structures of rotary pile and pile construction method using the same}

The present invention relates to a steel pipe connection structure of the pile pile and a pile construction method using the same, in particular a rotary to free the insertion and withdrawal of the mechanism required for grouting filling so that there is no obstacle protruding into the connection portion of the adjacent steel pipe in the longitudinal direction Steel pipe connection structure of pile and pile construction method using the same.

Rotary piles are introduced into the ground through rotation to give tip support with friction and spiral wings. Rotary piles also have inherent strength, resisting horizontal shear forces. As such, the principal friction, tip bearing and horizontal shear resistance are important factors that the rotary pile must have to support the foundation concrete structure.

In order to increase the principal friction and horizontal shear resistance, the cross-sectional diameter of the steel pipe should be increased, but the rotary pile is made of steel pipe with a small diameter of less than 200mm ~ 300mm, so it is difficult to achieve more resistance strength. In addition, the rotary pile causes frictional expansion, which causes the hole to expand to the upper periphery during rotational penetration.

In addition, the tip bearing capacity is dependent on the spiral wing, which causes the strata to loosen the strata during rotational penetration, resulting in excessive initial settlement upon load loading on the rotary pile. Therefore, if the settlement of the rotary pile exceeds the limit (for example, 1 inch), even if the bearing capacity of the steel pipe with high yield strength and high tensile strength is high, it cannot be used as a foundation pile.

In addition, the rotary pile has a small bearing capacity of about 50 to 60 tons, so that the load is increased when the load (or design load) is larger than 100 tons, for example, thereby increasing the additional construction cost.

Background art of the present invention is Korean Patent Registration No. 10-0686697, there is a support pile that serves both tension and compression. It is a pile embedded in the ground connected to a heavy-duty rotary output end, such as an earth drill or auger, a hollow pipe having a predetermined length, and forms an inclined sharp portion at its tip, and is connected to the rotary output end at its rear end. It is provided with a circular long main pipe having a connecting flange, wherein the outer circumferential surface of the main pipe is characterized in that it is provided with one or more swivel blades spirally rotated.

However, in the background art, since the tip bearing force depends only on the turning blades, there is a problem that settlement occurs under load due to the loose ground.

On the other hand, in order to reach the support pile up to the support layer, a plurality of main pipes are required to be connected to each other structure. In this case, the connection structure may be welded or bolted, but when bolted, it protrudes into the main pipe. In this case, if you want to insert a separate device into the main pipe for special purpose, the bolt becomes an obstacle, making it impossible. Therefore, a solution for this is required.

Korea Patent Registration No. 10-1011583 Korea Patent Registration No. 10-0566068

The object of the present invention is to provide a steel pipe connection structure of the rotary pile and a pile construction method using the same, so that there is no obstacle protruding into the connection portion of the adjacent steel pipe in the longitudinal direction, the insertion and withdrawal of the mechanism required for grouting filling is free. have.

Steel pipe connection structure of the rotary pile according to an embodiment of the present invention,

In a rotary pile comprising a plurality of steel pipes having the same outer diameter and one or more spiral wings on the outer circumferential surface and are interconnected in the longitudinal direction according to the penetration depth and penetrated into the strata,

The mutually adjacent steel pipes are characterized in that they have at least one pair of additional metal plates whose ends are overlapped on the outer circumferential surface close to the joint surface side, and are welded all around the joint surface after the cross sections are butted together.

Steel pipe connection structure of the rotary pile according to another embodiment of the present invention,

In connection part of mutually neighboring steel pipe,

A dilatation portion forcibly extending an inner diameter of one end portion and a plurality of bolt insertion holes penetrating the dilation portion;

Forming the same number of screw holes as the bolt inserting holes at the ends of the steel pipes inserted into the expanding portions;

A joint bolt inserted into the bolt insertion hole and screwed to the screw hole;

The joint bolt is characterized in that it is configured not to protrude to the inner diameter portion of the steel pipe located inside after fastening.

In connection part of mutually neighboring steel pipe,

A cylindrical coupling having a plurality of penetrating bolt insertion holes inserted into the outer diameter portion of either end of the steel pipe and fixed by welding;

Forming a screw hole equal to the bolt insertion hole on an end side of the steel pipe inserted into the cylindrical coupling;

Pile construction method using the steel pipe connection structure of the rotary pile according to the present invention,

Positioning the lower steel pipe perpendicular to the ground, and connecting the connecting socket to the upper end of the lower steel pipe and rotating penetration;

Separate the connecting socket from the lower steel pipe, and then raise the upper steel pipe vertically, butt the lower surface to the upper surface of the lower steel pipe, and then overlap a pair of additional metal plates on the outer peripheral surface of the upper and lower steel pipes. Welding to joint;

The connecting socket is connected to the upper steel pipe and then the upper and lower steel pipe is characterized in that the construction, including the step of rotating penetration into the ground.

According to the steel pipe connection structure of the rotary pile of the present invention and the pile construction method using the same, the connection part of the steel pipe adjacent to the longitudinal direction by welding the metal plate, or by forming a bulge at either end or using a cylindrical coupling It can prevent the tightening bolt from protruding inside. Therefore, the mechanism necessary to obtain a solidified layer by grouting filling is free to enter and take out into the steel pipe, so that the grout material can be infiltrated and solidified into the ground around the distal end of the desired lower steel pipe, thereby greatly improving the tip bearing capacity.

The following drawings, which are attached in this specification, illustrate the preferred embodiments of the present invention, and together with the detailed description thereof, serve to further understand the technical spirit of the present invention. It should not be construed as limited.
Figure 1a to 1c is a view of the various connections of the neighboring steel pipe of the rotary pile having a connection structure according to the present invention.
Figure 2 is an overall assembly state of the rotary pile having a connection structure according to the present invention.
3 is an exploded view of FIG. 1;
4 and 5 is a construction sequence diagram of a rotary pile having a connection structure according to the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below with reference to the embodiments shown in the accompanying drawings, but the present invention is not limited thereto.

The present invention is characterized in that the bolt does not protrude into the inner diameter of the steel pipe when connecting the connection of the steel pipes constituting the rotary pile with a bolt. That is, in the present invention, when the plurality of steel pipes are connected by bolts in the longitudinal direction, there is no protrusion of the bolts into the connection parts, so that the insertion of a mechanism used for a specific purpose is performed well.

&Lt; Embodiment 1 >

Rotary files 10 having one or more spiral wings 14 on the same outer diameter and outer circumferential surface as shown in FIGS. 1A and 2 and having a plurality of steel pipes 12a and 12b interconnected in the longitudinal direction and penetrated into the strata according to the penetration depth. ), The adjacent steel pipes 12a and 12b have at least one pair of additional metal plates 15 and 15 which are overlapped at both ends on the outer circumferential surface close to the joining surface side thereof, and are welded to the entire circumference of the joining surface after the cross sections are butted together. To be joined.

At this time, the pair of additional metal plates 15 and 15 may be joined to the lower side steel pipe 12a in a state in which the lower end portion of the upper side steel pipe 12b is welded in advance.

The pair of additional metal plates 15 and 15 are attached to the outer circumferential surfaces of the steel pipes 12a and 12b. Therefore, the inner surface of the additional metal plates 15 and 15 has the same curvature as the outer peripheral surface of the steel pipe 12a or 12b. Preferably, the joining surfaces of the steel pipes 12a and 12b lie in the center of the metallized plates 15 and 15.

In this way, the use of the additional metal plates 15 and 15 may remove elements protruding into the steel pipes 12a and 12b. In addition, the weld length with the steel pipes 12a and 12b is increased, so that the joint seam is ensured and the joint strength is improved.

&Lt; Embodiment 2 >

Rotary files 10 having one or more spiral wings 14 on the same outer diameter and outer circumferential surface as shown in FIGS. 1B and 2 and having a plurality of steel pipes 12a and 12b interconnected in the longitudinal direction and penetrated into the strata according to the penetration depth. ), A plurality of bolts penetrated through the expansion portion 12b-1 and the expansion portion 12b-1 forcibly extending the inner diameter of one end portion at the connecting portions of the adjacent steel pipes 12a and 12b. Insertion hole 122a is provided. In the present embodiment, the bolt insertion hole 122a is formed at a circumferential interval every 90 degrees. The bolt insertion holes 122a are arranged at regular intervals in the longitudinal direction as well as the circumferential direction. In this embodiment, all four bolt insertion holes 122a are formed in three rows in three rows, but the number of the bolt insertion holes 122a is not limited thereto.

In addition, the end of the steel pipe (12a) is inserted into the expansion portion (12b-1) is formed with the same number of screw holes 123 and the bolt insertion hole (122a). Therefore, the plurality of screw holes 123 and the bolt insertion holes 122a correspond one to one with each other when the steel pipes 12a and 12b are assembled.

A joint bolt 13 is inserted into the bolt insertion hole 122a and screwed into the screw hole 123. Therefore, the joint bolt 13 is provided in the same number as the bolt insertion hole 122a or the screw hole 123. In this case, the length of the joint bolt 13 does not exceed the sum of the thicknesses of both steel pipes 12a and 12b as shown in FIG. 3a.

Therefore, as shown in FIG. 3a, when the two steel pipes 12a and 12b are assembled, a joint bolt 13 is inserted into the bolt insertion hole 122a to be screwed to the screw hole 123. Therefore, the joint bolt 13 does not protrude to the inner diameter portion of the steel pipe 12a located inside after the joint bolt 13 is fastened.

&Lt; Third Embodiment >

Rotary files 10 having one or more spiral wings 14 on the same outer diameter and outer circumferential surface as shown in FIGS. 1C and 2 and having a plurality of steel pipes 12a and 12b interconnected in the longitudinal direction and penetrated into the strata according to the penetration depth. ), A cylindrical couple having a plurality of bolt insertion holes 11a penetrated at the connecting portions of adjacent steel pipes 12a and 12b and inserted into an outer diameter portion of either end of the steel pipes 12a and 12b and fixed by welding. The ring 11 is installed.

The bolt insertion hole 11a is provided circumferentially at intervals of 90 degrees. The bolt insertion holes 11a are arranged at regular intervals in the longitudinal direction as well as the circumferential direction. In this embodiment, all four bolt insertion holes 11a are formed in three rows in three rows, but the number of the bolt insertion holes 11a is not limited thereto.

At this time, the inner diameter of the cylindrical coupling 11 is inserted into the outer peripheral surface of the steel pipe 12a or 12b has the same diameter as the outer diameter of the steel pipe 12a or 12b. The length of the cylindrical coupling 11 is set to accommodate a certain length of each connecting end of the steel pipes 12a and 12b.

On the end side of the steel pipe 12a inserted into the cylindrical coupling 11, the same number of screw holes 123 as the bolt insertion holes 11a is formed. Therefore, the plurality of screw holes 123 and the bolt insertion holes 11a correspond one to one with each other when assembling the steel pipes 12a and 12b.

A joint bolt 13 is inserted into the bolt insertion hole 11a and screwed into the screw hole 123. Therefore, the joint bolt 13 is provided in equal numbers with the bolt insertion hole 11a or the screw hole 12a-1. In this case, the length of the joint bolt 13 does not exceed the sum of the thicknesses of the coupling 11 and the steel pipe 12a or 12b as shown in FIG. 1B.

Therefore, as shown in FIG. 1B, when the two steel pipes 12a and 12b are assembled, a joint bolt 13 is inserted into the bolt insertion hole 11a to be screwed to the screw hole 123. Therefore, the joint bolt 13 does not protrude to the inner diameter portion of the steel pipe 12a located inside after the joint bolt 13 is fastened.

Thus, by forming the rotary pile 10 so that the joint bolt 13 does not protrude into the inner diameter of the steel pipe 12a, the grout material (e.g., urethane resin, cement, etc.) is used to prevent tip settlement and increase tip bearing capacity. The construction of the rotary pile can be performed by tightening it. That is, the grout material through the grouting backflow prevention plate 20 drawn into the steel pipes 12a and 12b and the grouting injection pipe 22 screwed to the grouting backflow prevention plate 20 as shown in FIGS. 2 and 3. It can be injected to obtain a solidified layer.

First, as shown in FIG. 4 (a), the lower steel pipe 12a is connected to the rotary driving unit M of the drilling equipment (for example, auger, earth drill, etc.) from the top, and then rotated and inserted perpendicularly to the ground layer.

Next, the upper steel pipe 12b is connected immediately before the lower steel pipe 12a is completely inserted. At this time, the upper steel pipe (12b) and the lower steel pipe (12a) is connected through the selected connection structure of the above embodiments (Fig. 4 (b)).

For example, after separating the connecting socket 40 from the lower steel pipe 12b, the upper steel pipe 12b is erected vertically, but the lower surface is abutted on the upper surface of the lower steel pipe 12a, and then a pair of additional metal plates 15 and 15 are provided. ) Is superimposed on the outer circumferential surface of the connecting portion of the upper and lower steel pipes (12b, 12a) and welded to the front circumference of the metal sheet (15, 15) butt joint.

Next, the connecting socket 40 is connected to the upper steel pipe 12b again, and then, as shown in FIG. 4 (c), the steel pipes 12a and 12b are rotated and penetrated into the strata, and as shown in FIG. 20 and the grouting injection pipe 22 assembled therein are inserted into the steel pipes 12a and 12b. At this time, the grouting injection pipe 22 is screwed into the grouting backflow prevention plate 20 is drawn in the assembled state. When the grouting backflow prevention plate 20 reaches a predetermined depth, a urethane injection chamber is formed below the grouting backflow prevention plate 20.

Next, the upper part of the grouting injection pipe 22 is connected to the urethane injector 100, for example, and then urethane resin is pressurized. The injected urethane resin is discharged through the urethane discharge hole 125 of the lower steel pipe 12a and penetrates into the surrounding ground (Fig. 5 (b). At this time, the urethane resin is fine particles, so that even fine pores of the ground layer having clay particles are present. Therefore, the spiral wing 14 is supported by the solidified layer 200 which is solidified on the ground around the pile tip, so that the tip bearing capacity is further increased, and cement or chemical liquid may be injected instead of the urethane resin.

Thus, through the connection structure of the present invention, there is no protruding obstacle to the inside of the steel pipe, it is possible to insert the grouting backflow prevention plate 20 and the grouting injection pipe 22. Therefore, cement or urethane resin injected through the grouting injection pipe 22 solidifies the strata around the tip of the rotary pile 10 and increases its strength, thereby improving its bearing capacity.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is evident that many alternatives, modifications and variations will be apparent to those skilled in the art in light of the above teachings. will be. The invention is not limited by these variations and modifications, but is limited only by the claims appended hereto.

11: coupling
12a, 12b: steel pipe
125: urethane discharge hole
14: spiral wing
15: metal plate
122: coupling
11a, 122a: bolt insertion hole
123: screwdriver
20: Grouting Backflow Check Plate
22: grouting injection pipe

Claims

In a rotary pile comprising a plurality of steel pipes (12a, 12b) having one or more spiral wings (14) on the same outer diameter and outer circumferential surface and are interconnected in the longitudinal direction along the penetration depth to penetrate into the strata,
The mutually adjacent steel pipes 12a and 12b have at least one pair of additional metal plates 15 and 15 having both ends overlapped on the outer circumferential surface close to the joining surface side thereof, and after the cross sections are butted together, the joints are welded all around the joint surface. Steel pipe connection structure of rotary file.

In a rotary pile comprising a plurality of steel pipes (12a, 12b) having one or more spiral wings (14) on the same outer diameter and outer circumferential surface and are interconnected in the longitudinal direction along the penetration depth to penetrate into the strata,
In the connection part of mutually adjacent steel pipes 12a and 12b,
An enlarged portion 12b-1 forcibly extending the inner diameter of one end portion and a plurality of bolt insertion holes 122a penetrated through the expanded portion 12b-1;
Forming a screw hole 123 equal to the bolt insertion hole 122a at the end of the steel pipe inserted into the expansion part 12b-1;
A joint bolt 13 inserted into the bolt insertion hole 122a and screwed to the screw hole 123;
Steel pipe connection structure of the rotary pile, characterized in that the joint bolt 13 is configured not to protrude to the inner diameter portion of the steel pipe (12a) located in the inner side after the fastening.

In a rotary pile comprising a plurality of steel pipes (12a, 12b) having one or more spiral wings (14) on the same outer diameter and outer circumferential surface and are interconnected in the longitudinal direction along the penetration depth to penetrate into the strata,
In the connection part of mutually adjacent steel pipes 12a and 12b,
A cylindrical coupling 11 having a plurality of penetrating bolt insertion holes 11a inserted into an outer diameter portion of one of the steel pipes 12a and 12b and fixed by welding;
Forming a screw hole (123) equal to the bolt insertion hole (11a) on the end side of the steel pipe (12a) inserted into the cylindrical coupling (11);
A joint bolt 13 inserted into the bolt insertion hole 11a and screwed to the screw hole 123;
Steel pipe connection structure of the rotary pile, characterized in that the joint bolt 13 is configured not to protrude to the inner diameter portion of the steel pipe (12a) located in the inner side after the fastening.

Positioning the lower steel pipe 12a perpendicularly to the ground, connecting the connection socket 40 to the upper end of the lower steel pipe 12a, and rotating the pipe;
After disconnecting the connecting socket 40 from the lower steel pipe 12b, the upper steel pipe 12b is erected vertically, but the lower surface is abutted on the upper surface of the lower steel pipe 12a, and a pair of additional metal plates 15 and 15 are removed. Welding the joints of the upper and lower steel pipes (12b, 12a) to the outer circumferential surfaces of the joints and the front edges of the upper and lower steel pipes (12, 15a);
Reconnect the connection socket 40 to the upper steel pipe (12b) and then pile, using the steel pipe connection structure of the rotary pile, characterized in that the construction including the step of rotating in the upper and lower steel pipes (12b, 12a) to the ground Construction method.