KR20110038443A - Connecting method and connecting structure between footing and prestressed precast concrete pile - Google Patents

Abstract

PURPOSE: Coupling structure and construction method of a pre-stressed concrete pile and an extended base are provided to minimize the damage to a pile since a length control unit without a rebar is formed on the upper part of a PC(Pre-stressed Concrete) pile so that the upper part of the pile is cut easily and rapidly. CONSTITUTION: A coupling structure of a pre-stressed concrete pile and an extended base comprises a PC pile(1). The PC pile comprises a length control unit and a tendon arranging unit. The length control unit comprises a rebar inserting pipe. The rebar inserting pipe comprises an connecting rebar(102). The connecting rebar cuts a part from the length control unit to perform a task for arranging the head of the pile. The connecting rebar forms an extended base(200) on the concrete pile using concrete. The tendon arranging unit comprises tendon(101), to which tension has been in a pretension manner.

Description

Connecting method and connecting structure between footing and prestressed precast concrete pile}

The present invention relates to a coupling structure of the prestressed concrete pile and the expansion foundation used when constructing the expansion foundation of a structure such as a building structure, a bridge, a retaining wall, and the like. In constructing prestressed concrete piles (hereinafter, referred to as "PC piles") manufactured by a cast method, the structure has a structure in which rebars can be inserted later on the upper portion of the PC piles. Coupling structure and coupling of prestressed concrete piles and expansion foundations with tension material having a structure that facilitates easy to clean the head by the top cutting, which is configured to facilitate the operation of cutting and removing unnecessary parts in the It is about a construction method.

A PC pile is installed and an enlarged foundation is installed on the upper part.In order to connect the PC pile and the enlarged foundation integrally, the reinforcing bar integrated with the main body of the PC pile is longer than a certain length (usually more than 35 times the diameter of the bar). It must be purchased and settled within the base of expansion.

In general, the PC piles have a fixed length, while the depth of the piles in which the PC piles are constructed depends on the site situation. In practice, when ordering PC piles for pile construction, it is about 2-3m to the length of the pile that is planned in consideration of the drilling error and the rebar exposure height due to the inconsistent depth of the support layer. It is common to order piles in addition, and after installing the piles on the ground, it cuts and arranges the unnecessary upper part of the pile which protrudes above the ground. In particular, there is a limit to the length of the protrusion of the pile that can protrude above the ground in order to construct an enlarged foundation on the upper part of the pile, which can reinforce the horizontal reinforcement of the enlarged foundation if the pile top protrudes above the ground. Because there is not. Therefore, if the top of the pile protrudes above the ground beyond the limited length, the rest of the pile must be cut so that the protruding length of the pile is below the limited length.

In this situation, the reinforcing bars placed in the main body of the PC pile should be removed by cutting only the concrete without damaging them.The pile head is exposed by exposing the reinforcing bars by crushing and removing the concrete of the pile body without cutting the upper part of the pile collectively. Cleaning up can be time-consuming and expensive.

The present invention was developed to overcome the limitations and problems of the prior art as described above, and quickly and easily perform a pile head cleaning operation to cut and remove the unnecessary portion of the upper part of the pile protruding above the ground after installing the PC pile At the same time, the rebar is placed between the PC pile and the enlarged foundation so that the rebar can be embedded and settled within the enlarged base for a predetermined length or more, so that the PC pile and the enlarged foundation constructed on the upper portion thereof can be firmly combined with each other. For the purpose of

In the present invention, in order to achieve the above object, as a coupling structure of a PC pile consisting of a cylindrical concrete pile body having a hollow portion, and an expansion foundation formed by concrete pouring on the upper portion, the pile body of the PC pile, Has a structure consisting of a length adjusting part in which the reinforcing bar insertion pipe into which the base connection reinforcing bar is inserted in the lower direction is embedded, and a tension material arranging part in which the tension material is applied by the pretension method to reinforce the pile body. ; Unnecessary parts are cut from the upper part of the length adjusting unit in which the basic connection reinforcing bar is not inserted yet, thereby completing the pile head cleaning operation, and the basic connection reinforcing bar is inserted into and fixed to the reinforcing pipe insertion pipe; Concrete is installed so that the foundation reinforcing reinforcing bar projecting above the concrete pile body is embedded in the interior is provided with a combined structure of the composite pile and the enlarged foundation, characterized in that the expansion base is formed on top of the concrete pile.

In addition, in the present invention as a method of combining the expansion foundation by placing concrete on the upper part of the PC pile consisting of a cylindrical concrete pile body having a hollow portion, the reinforcement insertion pipe is inserted into which the foundation connection reinforcement is inserted from the upper direction to the lower direction Installing a PC pile having a pile body having a length body and a pile main body having a tension member arrangement in which a tension member is applied by a pretension method to reinforce the pile body; Performing a pile head cleaning operation by cutting a protruding portion greater than an insertion height of an enlarged base from an upper part of a length adjusting unit in which a foundation connection reinforcing bar is not yet inserted; Inserting and fixing the basic connection reinforcing bars embedded in the expanded foundation into the reinforcing bar insertion pipes; And a step of placing the concrete so that the foundation connection reinforcing bars protruding above the upper portion of the pile body are embedded therein to integrally form an enlarged foundation on the upper portion of the PC pile. A joint construction method is provided.

According to the present invention, in preparation for cutting the upper part of the PC pile according to the planned height, at the time of cutting the upper part of the pile, the upper part of the pile is easily formed by forming a length adjusting part in which the reinforcing bar is not arranged on the upper part of the PC pile. It can be cut quickly and collectively, and the rebar is placed between the PC pile and the expansion foundation while minimizing damage to the pile body, and the rebar is embedded and settled in the expansion foundation over a certain length. The expansion base is firmly combined with each other.

Hereinafter, with reference to the drawings showing an embodiment of the present invention will be described a specific configuration of the present invention.

1 shows a schematic exploded cross-sectional perspective view of a PC pile 1 according to the invention. FIG. 2 is a schematic cross-sectional view showing a state in which the PC pile 1 according to the present invention is installed in the ground, and in FIG. 3, the length of the length adjusting part A is arranged after the state of FIG. 2. A schematic cross-sectional view is shown showing a shape in which an enlarged foundation 200 is installed on the top.

PC pile 1 of the present invention is composed of a cylindrical concrete pile body having a hollow portion 10, the prestress tension member 101 is disposed in the pile body over the entire length. The prestressed tension member 101 is tensioned in a pretensioning manner. That is, to produce the PC pile (1) by centrifugal molding the concrete in a state in which the tension member 101 in advance.

The PC pile 1 of the present invention, as shown in Figure 1, the length adjustment portion is embedded with a reinforcing rod pipe 13 is inserted into the foundation body reinforcement reinforcement 102 in the pile body from the top to the bottom ( A) and the tension member 101 for reinforcing the pile body may be divided into a tension member arrangement portion B to remain.

As will be described later, when the pile body of the PC pile 1 is cut by the length adjusting part A, the tension member 101 continues to settle in the pile body of the PC pile 1 to exert a tension force. The tension member 101 in the tension member arrangement part B may further include an intermediate fixing member 110 such as a nut or a wedge. As shown in the figure, the intermediate fixing member 110 is preferably located at the upper start portion of the tension member arrangement (B). An example of the intermediate fixing member 110 may be a nut. A nut is formed on the outer surface of the tension member 101 to fasten the nut to the thread, thereby integrally attaching the nut to the tension member 101 as the intermediate fixing member 110. It can be combined to install, the nut or wedge may be coupled to the tension member 101 by welding. The intermediate fixing member 110 may be provided in plurality in the tension member arrangement portion (B) section. In the drawing, member number 112 is an end fixing member 112 made of a nut or the like provided to fix the tension member 101 at the upper end of the tension member 101.

The length adjustment part A corresponding to the upper portion of the PC pile 1 is provided with a reinforcing bar insertion pipe 13 into which the basic connection reinforcing bar 102 is to be inserted. The reinforcement pipe 13 may be formed of a corrugated pipe having wrinkles formed on the surface of the pile body in order to enhance the bonding force with the concrete of the pile body, and various methods such as forming protrusions on the surface or roughening the surface itself. It may have a surface configuration to promote the adhesion. The reinforcement pipe 13 may be coupled to the tension member 101 at an outer surface thereof, or may be located between the tension member 101. When the outer surface of the reinforcing pipe 13 is coupled to the tension member 101, the outer surface of the tension member 101 and the outer surface of the reinforcing pipe 13, which extends to the length adjusting part A and are arranged to be long, are welded or the like. They are joined together and integrated by a method. Unlike the embodiment illustrated in the drawings, when the reinforcing pipe 13 is separated from the tension member 101 and positioned between the tension members 101, the reinforcing pipes (not shown) such as a band reinforcement or a spiral reinforcement are mediated. As such, the tension member 101 and the rebar insertion pipe 13 may be integrated. In this way, when the reinforcement insertion pipe 13 is integrated with the tension member 101, the reinforcement insertion pipe 13 is fixed when the PC pile 1 is manufactured to maintain its position.

In addition, when the reinforcement insertion pipe 13 is integrated with the tension member 101 as described above, it is advantageous to fix the tension member 101 even if the pile body cut of the length adjusting part A is made as described below. When the length adjustment unit (A) is cut as described below, the tension member (101) disposed in the length adjustment unit (A) is also cut, and the reinforcement insertion pipe (13) remaining in the main body after cutting is used to fix the tension member (101). It also functions as an apparatus, and the end portion of the tension member 101 is still fixed to the pile body in the length adjustment portion A by the reinforcing pipe 13 remaining in the length adjustment portion A. The tension state of 101 is maintained. In order to enhance the bonding strength with the pile body, the reinforcement pipe 13 preferably has a shape such as a corrugated pipe whose outer surface is rough. Of course, in addition to the corrugated pipe, the bond strength of the pile body with the concrete may be improved by various methods such as forming protrusions on the surface of the reinforcement insertion pipe 13 or roughening the surface itself.

In the present invention, the reinforcing bar coupling member 30 may be provided at the lower end of the reinforcing bar insertion pipe 13. The lower portion of the basic connection reinforcing bar 102 is inserted into the reinforcing bar insertion pipe 13 is later coupled to the rebar coupling member (30). Of course, the rebar coupling member 30 may be omitted, and even if the rebar coupling member 30 is present, the lower end portion of the basic connection reinforcing bar 102 may not be coupled with the rebar coupling member 30.

In addition, the vertical reinforcing bars 106 may be additionally disposed in the tension member arrangement part B to reinforce the bending strength as described later. In this case, the upper end of the vertical reinforcing bar 106 is coupled via the reinforcing bar coupling member 30, or overlapped with the reinforcing bar insertion pipe 13 (member No. 106 see FIG. 4 to be described later).

Next, with reference to Figures 2 and 3 will be described in more detail the coupling structure and coupling construction method of the PC pile 1 and the expansion foundation 200 according to the present invention.

PC pile (1) having the above structure is buried in the ground. When the PC pile 1 is buried in the ground, as shown in FIG. 2, the length adjustment part A is not yet inserted with the foundation connection reinforcing bar 102. In this state, the pile head cleaning operation is performed to cut and remove an unnecessary portion of the upper portion of the PC pile 1, that is, the upper portion of the pile body protruding beyond the allowable height that may protrude into the enlarged foundation. Since the basic connection reinforcing reinforcement 102 does not exist in the state that does not exist it can be cut at a time using a cutter or the like. In the conventional technology described above, since the reinforcing bar exists in the pile body during the pile head cleaning operation step, and the reinforcing bar should be left exposed, the concrete around the reinforcing bar is removed by the length of the anchorage (about 1 m). You have to perform a difficult task. However, in the present invention, since cutting the pile in the absence of the reinforcing bar as described above to perform the pile head to clean the operation can be carried out very easily compared to the prior art and accordingly the effect of reducing the cost, reducing the working time Can be. In particular, when ordering the piles do not need to secure additional pile lengths as much as the exposed length of the rebar, the length of the pile to be ordered that much reduces the resulting cost.

When the length adjusting portion (A) is cut in the absence of the foundation connection reinforcing bars (102), the tension member (101) disposed in the length adjusting portion (A) is also cut, but the tension member (101) is inserted into the reinforcing pipe (13). Because it is combined with) it can minimize the relaxation of the tension force of the tension member (101). In particular, when the intermediate member 110 is provided in the tension member 101 in the tension member arrangement part B, tension relaxation may be further reduced by fixing the tension member 101 by the intermediate fixing member 110. .

After cutting the length adjustment part (A) as described above, after performing the pile head to clean the work to insert the basic connection reinforcing bars 102 in the reinforcement insertion pipe 13 as shown in Figure 3 to reinforce the head. By injecting grout material such as epoxy, cement milk, etc. into the reinforcing pipe 13, the basic connection reinforcing bar 102 may be firmly installed in the reinforcing pipe 13. At this time, the upper part of the foundation connection reinforcing bar 102 is protruded from the upper end of the pile body to a height necessary to be embedded and fixed in the expansion base.

After inserting and fixing the basic connection reinforcing bar 102 to the reinforcing bar insertion pipe 13 in this way, as shown in FIG. 3, the concrete 21 is poured on the upper part of the PC pile 1 so that the PC pile ( Integral to the upper part of 1) to form an enlarged foundation 200. At this time, as shown in the figure, the portion protruding to the outside of the foundation connection reinforcing bars 102 disposed on the PC pile 1 is embedded in the expansion base 200.

When the concrete 21 for forming the expansion base 200 is poured, the concrete 21 is filled into the hollow portion 10 of the PC pile 1, to limit the inflow depth as necessary In order to block the plate 100 in the hollow portion 10 of the PC pile (1). At this time, as shown in FIG. 3, the blocking plate may be mounted on the locking step 11 that is pre-installed in the pile hollow in the manufacturing step. Through such a configuration, the expansion foundation 200 is integrally coupled to the upper portion of the composite pile of the present invention that the lower pile 1 and the PC pile 1 are integrally formed.

PC pile 1 according to the present invention, when inserting the foundation connection reinforcing bars 102 may further install the foundation connection reinforcing bars 102 as needed in the field. Therefore, there is an advantage that the moment resistance of the pile can be further increased by easily further installing the foundation connection reinforcing bars 102 in accordance with the size of the bending moment acting on the upper portion of the pile.

FIG. 4 is a view corresponding to FIG. 2, which is a schematic cross-sectional view showing an embodiment in which the vertical rebar 106 is additionally disposed in addition to the tension member arrangement B. Referring to FIG. In the embodiment shown in Figure 4 is connected to the reinforcing bar insertion pipe 13, the vertical reinforcement 106 is further reinforced to the tension member arrangement (B). Specifically, as shown in the drawings, when the rebar coupling member 30 is present, a vertical rebar 106 is additionally disposed in the tension member arrangement part B, and the upper end of the vertical rebar 106 is a rebar coupling member. Vertical reinforcing bars 106 may be further provided in the tension member arrangement portion B in a form coupled to the lower portion of the 30. Through the arrangement of the vertical reinforcing bars 106 it is possible to further increase the pile stiffness in the tension member arrangement (B). Of course, in the case where the vertical reinforcing bars 106 are further disposed in the tension member arranging unit B, the upper part of the vertical reinforcing bars 106 is not provided without the reinforcing bar coupling member 30 and the reinforcing pipes 13 are disposed. It can also be connected by folding. Other configurations are the same as the above-described embodiment, and thus repeated descriptions thereof will be omitted.

1 is a schematic exploded cross-sectional perspective view of a PC pile according to the present invention.

FIG. 2 is a cross-sectional view schematically illustrating a state in which the PC pile shown in FIG. 1 is installed in the ground.

FIG. 3 is a cross-sectional view schematically illustrating a shape in which an enlarged foundation is installed on an upper part of the connection bar in the state shown in FIG.

4 is a view corresponding to FIG. 2, which is a schematic cross-sectional view of an embodiment according to the present invention in which a vertical reinforcing bar is further placed in a tension member arranging unit.

* Description of the symbols for the main parts of the drawings *

1: PC stake

101: tension material

102: foundation connection rebar

Claims (3)

As a coupling structure of the PC pile (1) consisting of a cylindrical concrete pile body having a hollow portion (10) and the expansion foundation (200) formed on the top by concrete pouring, The pile body of the PC pile (1), the length adjustment portion (A) in which the reinforcing rod insertion pipe 13 into which the basic connection reinforcing bars 102 are to be inserted from the top to the lower direction and the reinforcement of the pile body It has a structure consisting of the tension member arrangement portion (B) in which the tension member 101 is applied to the tension force by the pre-tension method; Unnecessary portions are cut from the upper part of the length adjusting part A in a state in which the basic connection reinforcing bars 102 have not yet been inserted, thereby completing the pile head cleaning work, and connecting the basic connection reinforcing bars 102 to the reinforcing pipe insertion 13. It is inserted and fixed; Combination of the PC pile and the expansion foundation, characterized in that the concrete is laid so that the foundation connection reinforcing bars 102 protruding above the concrete pile body is embedded in the interior of the concrete pile rescue. The method of claim 1, Tension material arrangement (B) is a coupling structure of the PC pile and the expansion base, characterized in that the vertical reinforcement 106 is further reinforcement. As a method of combining the expansion foundation 200 by placing concrete on the upper portion of the PC pile (1) consisting of a cylindrical concrete pile body having a hollow portion 10, A tension adjusting part (A) in which the reinforcing bar insertion pipe (13) into which the base connection reinforcing bar (102) is inserted from the upper part to the lower part is embedded, and the tension member to which the tension force is applied by the pretension method for the reinforcement of the pile body ( Installing a PC pile 1 having a pile body having a structure of a tension member arrangement portion B in which 101 is remaining; Performing a pile head cleaning operation by cutting a protruding portion greater than an insertion height of the enlarged foundation 200 in the upper part of the length adjusting part A in which the basic connection reinforcing bar 102 is not yet inserted; Inserting and fixing the basic connection reinforcing bars (102) embedded in the enlarged foundation (200) to the reinforcing bar insertion pipes (13); And Placing concrete so that the foundation connection reinforcing bars 102 protruding above the pile body is embedded therein, and integrally forming the expansion foundation 200 on the upper portion of the PC pile. Combined construction method of pile and expansion foundation.

Images