KR101058520B1 - Earth retaining wall using phc pile and construction method of the same - Google Patents

Abstract

PURPOSE: An earth retaining wall using PHC piles and a construction method thereof are provided to reduce construction time by previously assembling a reinforcing body for reinforcing a stress transfer beam. CONSTITUTION: An earth retaining wall using PHC piles comprises Prestressed High-strength Concrete piles(10) and a stress transfer beam(20). The PHC piles are installed along the border line of a lot in a row. A pair of grouting grooves(111) are formed on the outer surfaces of the PHC piles. Each PHC pile has a hollow. The stress transfer beam comprises a reinforcing body and concrete. The reinforcing body comprises a pair of base plates, multiple web reinforcing bars, upper reinforcing bars, a pair of middle reinforcing bars, vertical reinforcing bars and spiral reinforcing bars. The concrete is placed in the hollows and tops of the PHC piles.

Description

Earth Retaining Wall Using PHC Pile And Construction Method Of The Same}

The present invention relates to a retaining wall composed of a PHC pile and a construction method thereof.

The clogging method can be classified into various types according to the type of the retaining wall to maintain the independence of the back soil sediment and the type of support (structure) to support it. The earthen wall includes H pile + earth plate, steel pile, CIP (Cast in Place Pile), SCW (Soil Cement Wall), Diaphragm Wall (Slurry Wall), etc. Ground anchor method, Soil nailing method and the like.

The earthquake wall or earth wall was originally a temporary structure for the purpose of resisting the side pressures such as earth pressure and water pressure that occur during the foundation excavation work. The purpose of use is diversified.

In particular, in recent years, due to the appearance of continuous cast-in-place reinforced concrete walls, which are developed in response to pollution prevention such as noise and settlement, they are not only used as temporary temporary wall, but also used as part of the building body such as foundation pile and seismic wall.

In order to select the most effective method among the various screening methods, the soil condition, site condition, impact on the site, construction cost, construction period, and workability should be considered.

It is an object of the present invention to provide a retaining wall composed of a PHC pile and a construction method thereof that can serve as a pile for supporting a ground layer structure and at the same time as an external formwork for constructing a basement wall.

According to a preferred embodiment of the present invention, a pair of order grouting grooves, which are constructed in a line along the ground boundary line and have a predetermined eccentric distance to the center line passing through the center of the cross section, are formed on the outer circumferential surface and have hollows therein. Multiple PHC files; And a pair of base plates disposed on the upper surfaces of the PHC piles in a direction crossing the PHC piles, parallel to each other, parallel to the base plates at regular intervals along the longitudinal direction of the base plates. Reinforcing bar, the upper bar is installed in parallel with the base plate to connect the upper part of the abdominal reinforcement, a pair of intermediate reinforcement is installed in parallel with the upper bar to connect the sides of the abdominal reinforcement, inserted into the hollow of each PHC pile A reinforcement comprising a plurality of vertical reinforcing bars of cylindrical shape and spiral reinforcement inserted into the hollow of each PHC pile and surrounding the vertical reinforcing bars of cylindrical shape, and a top and a hollow of each PHC pile to receive the reinforcing body therein. Retaining wall made of PHC pile, characterized in that it comprises a stress shear beam made of concrete to be poured Ball.

According to another suitable embodiment of the present invention, the abdominal reinforcement has a shape that is bent in an inverted V-shaped or c-shaped with the legs.

According to another suitable embodiment of the present invention, it further comprises a plurality of transverse bars disposed in a direction perpendicular to the longitudinal direction of the intermediate reinforcement and coupled to the abdominal reinforcement to fix the position of the intermediate reinforcement.

According to another suitable embodiment of the present invention, a pair of order grouting grooves having a predetermined eccentric distance rearward with respect to the center line passing through the center of the cross section along the ground boundary line is formed on the outer circumferential surface and has a hollow PHC pile. Constructing in the underground; Arranging the tofu of each PHC file; Cylindrical reinforcing bar is constructed by assembling a plurality of vertical and spiral reinforcing bars into the hollow of each PHC pile, and by assembling a pair of base plates, a plurality of abdominal reinforcing bars, an upper reinforcing bar and a pair of intermediate bars Installing the constructed triangular truss so as to be located on an upper surface of the PHC pile; And installing the formwork and placing the concrete so that the reinforcement is embedded and filled in the hollow of the PHC pile, and a construction method of the retaining wall constituted by the PHC pile is provided.

According to another suitable embodiment of the present invention, after the step of constructing the PHC pile further comprises the step of injecting the grout into the order grouting groove.

According to the present invention, the stress transmission beam is firmly connected to the upper end of the PHC pile, so that the PHC piles can be integrally behaved against the side pressure acting on the retaining wall in accordance with the excavation.

In addition, the PHC pile acts as a pile to support the ground layer structure, so that the load transmitted from the ground layer wall or column through the stress transmission beam can be effectively transmitted to the PHC pile so that the meteorological layer wall or column can be constructed as close to the ground boundary as possible. Therefore, the use of the land can be improved.

In addition, since the reinforcement to reinforce the stress transmission beam may be pre-assembled, the construction period for constructing the retaining wall is shortened and the workability is improved.

The following drawings, which are attached in the present specification, illustrate exemplary embodiments of the present invention, and together with the detailed description of the present invention, serve to further understand the technical spirit of the present invention. It should not be construed as limited.
1 is a perspective view showing a retaining wall according to the present invention, Figure 2 is a cross-sectional view (sectional view taken along the line AA of Figure 1) of the retaining wall.
3 is a perspective view showing a state in which the reinforcement constituting the stress transmission beam according to an embodiment of the present invention is installed on the upper surface of the P pile, Figure 4 is a plan view.
5 is a perspective view showing a state in which the reinforcement constituting the stress transmission beam according to another embodiment of the present invention is installed on the upper surface of the P pile, Figure 6 is a plan view.
Figure 7 shows the construction method of the retaining wall according to the present invention in order.

In the following the present invention will be described in detail with reference to the embodiments shown in the accompanying drawings, but the embodiments presented are exemplary for a clear understanding of the present invention is not limited thereto.

1 is a perspective view showing a retaining wall according to the present invention, Figure 2 is a cross-sectional view (sectional view taken along the line A-A of Figure 1).

1 and 2, the retaining wall according to the present invention includes a plurality of PHC piles (10) constructed in a line in the ground, and a stress transmission beam 20 for connecting them to each other across the top of the PHC pile do.

PHC pile 10 may be constructed by the embedded pile method. That is, the cement paste is injected while drilling the ground along the ground boundary line, and the PHC pile 10 is inserted and finally struck, or the tip fixing liquid and the main surface fixing liquid are injected while the ground is drilled, and the PHC pile 10 is repeatedly inserted. PHC file 10 can be installed in a line in the ground. However, if the effects of noise or vibration can be neglected, it is also possible to construct by type method.

PHC file 10 applied to the present invention can be applied to a known PHC file, but in that case there is a disadvantage that a separate process may be required for the order. Thus, in the present invention, as shown in Figure 2, PHC pile 10 having a pair of order grouting groove 111 is formed with a predetermined eccentric distance e to the rear with respect to the center line CL passing through the center of the cross section on the outer peripheral surface ).

Thus, a pair of order grouting groove 111 is formed to have a predetermined eccentric distance (e) to the rear with respect to the center line (CL) passing through the center of the cross section has the advantage that can be constructed as close as possible. If a pair of order grouting grooves 111 are formed on the center line CL passing through the center of the cross section, the grouting agent is spaced apart from each other to allow the grouting agent to spread to the rear of the pile, and also to prevent the grouting agent from leaking forward. Although it is necessary to take a countermeasure, when the degree grouting groove 111 has a predetermined eccentric distance e rearward with respect to the center line CL passing through the center of the cross section as in the present invention, the grouting agent is brought into close contact with the adjacent pile. It can be prevented or minimized.

As an injection method of the grouting agent (chemical liquid), a known LW method (Lables Wasser Glass), SCW method (Special Chemical Grouting Method), JSP method (Jumbo Specila Pile), etc. may be selectively applied.

In addition, in the past, the diameter of the drilling hole needed to be drilled about 10 cm larger than the diameter of the pile, but when applying the PHC pile 10 according to the present invention, the diameter of the drilling hole can be made much smaller, so that the PHC pile 10 is connected to the earth boundary. Construction is possible as close as possible.

When the construction of the PHC pile is completed, clean the head of the PHC pile before installing the stress transfer beam. At this time, the head of the PHC pile is cleanly cut to the steel wire by a cutter.

After the PHC pile 10 is constructed and the head is arranged, a stress transmission beam 20 is installed to connect them to each other across the top of the PHC pile 10. The stress transmission beam 20 is composed of a reinforcement and concrete that is reinforced by the reinforcement and connects them to each other across the top of the PHC pile 10.

Figure 3 is a perspective view showing a state in which the reinforcement constituting the stress transmission beam according to an embodiment of the present invention is installed on the upper surface of the P pile, Figure 4 is a plan view.

As shown in FIG. 3, the reinforcement 20a constituting the stress transmission beam 20 according to the present invention is provided with respect to the pair of base plates 21a and 21b and the base plates 21a and 21b. A plurality of abdominal reinforcement (22), the upper reinforcing bar 23, and a pair of intermediate reinforcement (24a), a pair of intermediate reinforcement (24a) and 24b that connects the abdominal reinforcement (22) to each other vertically spaced ), A plurality of vertical bars 26 and vertical bars 26 inserted into the hollow 112 of the PHC pile 10 and having an upper end connected to the cross bars 25 to fix the position of It includes a spiral reinforcing bar 27.

The pair of base plates 21a and 21b are each composed of a strip-shaped steel sheet having a constant thickness and a longer length than the width, and they are arranged in a direction crossing the PHC piles 10 on the upper surface of the PHC pile 10. Parallel to each other in the direction of the retaining wall). PHC pile (10) is to clean the head after the construction at this time, because the cutting to clean the pile including the steel wire by the cutter, the seat plate fixed to the head of the pile is also removed abdominal reinforcement (22) on the upper surface of the PHC pile (10) It is difficult to fix it. The base plates 21a and 21b provide a surface on which the abdominal reinforcement 22 can be welded.

On the upper surface of the base plates 21a and 21b, a plurality of abdominal reinforcing bars 22 are welded at regular intervals along the longitudinal direction of the base plates 21a and 21b perpendicular to the surface. Abdominal reinforcing bar 22 is bent in a substantially inverted V-shaped shape and has a leg portion 222 extending horizontally at each end. The abdominal reinforcing bar 22 may be bent in multiple stages, such as steel bar, deformed reinforcing bar, and the leg part 222 and the inverted V-shaped part 221 may be integrally formed. The leg portion 222 may be bent to be retracted inwardly or spread outwardly and welded to the upper surfaces of the base plates 21a and 21b.

The upper reinforcement 23 is installed to connect the upper part of the abdominal reinforcement 22 to each other, and the intermediate reinforcement 24a and 24b are installed to connect the side surfaces. The upper reinforcement 23 is installed in parallel with the base plate (21a) (21b) to connect the upper portion of the abdominal reinforcement (22) to each other. The upper reinforcement 23 is disposed inside the bent portion of the inverted V-shaped portion 221 of the abdominal reinforcement 22 and may be connected to the abdominal reinforcement 22 by welding. Intermediate reinforcing bar (24a) (24b) is composed of a pair and installed in parallel with the upper reinforcing bar 23 to connect each side of the abdominal reinforcement (22) with each other. The intermediate reinforcing bars 24a and 24b may be disposed in parallel with the upper reinforcing bar 23 at the middle height of the abdominal reinforcing bar 22 and connected to the abdominal reinforcing bars 22 by welding. In the figure, the upper reinforcement 23 is disposed inside the bent portion of the inverted V-shaped portion 221 of the abdominal reinforcement 22 and the intermediate reinforcement 24a and 24b are disposed outside the abdominal reinforcement 22. However, the arrangement position is not limited thereto, and the installation positions of the intermediate bars 24a and 24b may also be installed higher or lower than the middle height of the abdominal reinforcement 22.

In order to fix the position of the intermediate bars 24a and 24b, a plurality of transverse bars 25 disposed in a direction perpendicular to the longitudinal direction of the intermediate bars 24a and 24b and parallel to the upper surface of the PHC pile It is coupled to the rebar (22). Therefore, the number of the cross bars 25 installed corresponds to the number of the abdominal bars 22. Hook portions 251 may be formed at both ends of the cross bar 25 so that the intermediate bars 24a and 24b may be more easily assembled. The hook portion 251 may, for example, be bent to have an angle of 60 degrees or less with respect to the horizontal plane. Alternatively, the intermediate bars 24a and 24b may be welded directly to the abdominal reinforcement 22 instead of being secured to the abdominal reinforcement 22 by the transverse reinforcement 25.

A plurality of vertical rebars 26 are installed to be inserted into the hollow 112 of each PHC pile 10. The vertical rebar 26 is disposed along the circumference of the hollow of the PHC pile and each vertical rebar 26 is spaced from each other. Accordingly, the vertical rebar 26 is inserted into the hollow 112 of the PHC pile 10 while forming a cylindrical shape. The upper ends of the vertical bars 26 of some of the plurality of vertical bars 26 are connected to the transverse bars 25. For convenience of assembly, a hook portion may be formed at an upper end of the vertical rebar 26 connected to the cross rebar 25. Alternatively, a portion of the vertical reinforcement 26 may be welded to the abdominal reinforcement 22.

The spiral reinforcement 27 is installed to surround the vertical rebar 26 from the outside in order to fix the positions of the plurality of vertical rebars 26. Spiral reinforcing bar 27 may be coupled to the vertical bar 26 by welding at the intersection with the vertical bar (26).

The reinforcement constructed as described above welds a plurality of abdominal reinforcements 22 to a pair of base plates 21a and 21b, and welds the upper reinforcement 23 and the transverse reinforcement 25 to the abdominal reinforcement 22, and then The reinforcing bars 24a and 24b are welded to the cross bars 25 to form a truss having a triangular shape, which is located on the upper surface of the PHC pile 10 and the spiral reinforcing bars 27 to the plurality of vertical bars 26. Welding to form a cylindrical rebar network is inserted into the hollow 112 of the PHC pile 10 is fixed. The depth at which the cylindrical reinforcing bar (26) combined with the vertical rebar (26) and the spiral reinforcing bar (27) is inserted into the hollow 112 of the PHC pile 10 may be inserted slightly longer than the diameter or diameter of the PHC pile 10. However, the insertion depth is not limited thereto, and the PHC pile 10 and the stress transmission beam 20 may be integrally formed with respect to the cross-sectional force acting on the joint of the head and the stress transmission beam 20 of the PHC pile 10. Depth. Forming plate (not shown) may be fixed using the vertical rebar 26 to adjust the depth of the concrete filled in the hollow 112 of the PHC pile 10.

After the installation of the reinforcement (20a) is completed, the formwork is installed, and then the concrete 28 is poured and hardened. At this time, the concrete 28 is filled in the hollow 112 of the PHC pile 10 so that the stress transmission beam 20 and the PHC pile 10 are integrated. In this way, the stress transmission beam 20 formed on the upper portion of the PHC pile 10 may have a shape such as a conventional T-shaped cross section beam or a rectangular cross section beam. And a vertical member such as a column or a wall of the ground layer structure is installed on the stress transmission beam 20. In this embodiment, the structure of the reinforcement 20a embedded in the concrete 28 is composed of an inverted V-shaped triangular truss overlapping the two planar trusses to effectively reinforce the stress transmission beam for supporting the vertical member of the upper layer structure, Concrete filled in the PHC pile 10 is reinforced with a cylindrical rebar network composed of vertical rebar and spiral rebar. Therefore, the stress transmission beam 20 and the PHC pile 10 behave as one body, thereby transferring the load transmitted from the ground layer wall or the pillar to the PHC pile 10, and to the PHC pile against the side pressure acting on the retaining wall upon excavation. The PHC files can be linked together so that they act integrally.

5 is a perspective view showing a state in which the reinforcement constituting the stress transmission beam according to another embodiment of the present invention is installed on the upper surface of the P pile, Figure 6 is a plan view.

The reinforcement 20b according to the present embodiment has the shape of the reinforcement 20a and the abdominal reinforcement 22, the number of the upper reinforcement 23 and the intermediate reinforcement 24a and 24b and the transverse reinforcement according to the embodiment described above. There is a difference in whether or not 25 is provided. For simplicity, repeated descriptions of the same elements as the elements constituting the reinforcement according to the above-described embodiments, that is, the base plate, the vertical rebar and the spiral rebar, will be omitted.

In the present embodiment, the abdominal reinforcing bar 22 'is bent in an approximately C-shape and has legs 222 extending horizontally at each end. The abdominal reinforcing bars 22 'may be bent in multiple stages such as steel bars, deformed bars, and the like to form the leg part 222 and the c-shaped part 221 integrally. The leg portion 222 may be bent to be retracted inwardly or spread outwardly and welded to the upper surfaces of the base plates 21a and 21b. When bent inwardly, the vertical portion 221a of the c-shaped portion 221 is formed to extend vertically at the end in the width direction of the base plates 21a and 21b, thereby forming a larger cross section of virtual concrete. And the more stress transfer beam can thus have a greater load capacity. In addition, by bending the abdominal reinforcing bar 22 'in a c-shape, the vertical rebar 26 and the spiral reinforcing bar 27 can be positioned to protrude further from the upper surface of the PHC pile, i.e., deeper into the stress transmission beam. As a result, the reinforcement of the stress transfer beams is further strengthened, and the coupling between the stress transfer beams and the PHC piles is further strengthened, and the stress transfer at the junction of the stress transfer beams and the PHC piles is more sure.

The upper reinforcing bar 23 is composed of at least two and is installed in parallel to the base plate (21a) (21b) to connect the horizontal portion (221b) of the abdominal reinforcement (22) with each other. In the drawing, the lower part of the horizontal portion 221b of the abdominal reinforcement 22 of the three upper reinforcement 23 was welded in parallel to the base plates 21a and 21b, but the number of the upper reinforcement 23 is not limited thereto. Of course, the installation position can also be installed above the horizontal portion.

The intermediate reinforcing bars 24a and 24b are formed in at least two pairs and are installed in parallel to the upper reinforcing bars 23 so as to connect the vertical portions of the abdominal reinforcing bars 22 to each other. In the drawing, three pairs of intermediate bars 24a and 24b were welded in parallel to the upper bars 23 inside the vertical portions 221a of the abdominal bars 22, but the number of intermediate bars 24a and 24b was welded. Is not limited thereto, and the installation position thereof may also be installed outside the vertical portion 221a. In addition, it can be coupled to the abdominal reinforcement (22) using a cross bar as in the above-described embodiment.

In the present embodiment, the abdominal reinforcement 22 'is bent in a c-shape as described above, and the abdominal reinforcement 22 is surrounded by a plurality of upper reinforcement 23 and a plurality of pairs of intermediate reinforcements 24a and 24b. As a result, the stress transfer beam can have a higher load capacity, the bond between the stress transfer beam and the PHC pile becomes more robust, and the stress transfer at the junction of the stress transfer beam and the PHC pile becomes more reliable.

Hereinafter will be described the construction method of the retaining wall according to the present invention.

First, the PHC piles 10 having a predetermined eccentric distance e and a pair of order grouting grooves 111 are formed in a row with respect to the center line CL passing through the center of the cross section on the outer circumferential surface along the ground boundary line. do. As described above, the PHC pile 10 may be constructed by an embedded pile method or a type method. In order to order the PHC piles 10 constructed in a line, the chemical solution (the grout) may be injected into the order grouting groove 111.

Next, the tofu of the PHC file 10 is arranged. At this time, the head of the PHC pile 10 is cleanly cut to the steel wire by a cutter.

Next, the reinforcement 20a, 20b constructed and assembled as described above and brought into the site is installed. In other words. Cylindrical reinforcing bar network formed by assembling a plurality of vertical reinforcing bars 26 and spiral reinforcing bars 27 is inserted into the hollow 112 of each PHC pile 10, and a pair of base plates 21a and 21b are provided. A truss in the form of a triangular or quadrangle formed by assembling the abdominal reinforcing bar 22, one or more upper reinforcing bars 23, and one or more pairs of intermediate reinforcing bars 24a and 24b to the upper surface of the PHC pile 10 Position it.

Finally, after the formwork is installed, the concrete 28 is poured and hardened. At this time, the concrete 28 is filled in the hollow 112 of the PHC pile 10 so that the stress transmission beam 20 and the PHC pile 10 are integrated.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it will be understood by those skilled in the art that various changes and modifications may be made without departing from the spirit and scope of the invention . The invention is not limited by these variations and modifications, but is only limited by the scope of the appended claims.

10: PHC file
111: Order Grouting Home
20: stress transfer beam
20a, 20b: reinforcement
21a, 21b: base plate
22: abdominal reinforcement
23: upper rebar
24a, 24b: middle bars
25: transverse rebar
26: vertical rebar
27: spiral rebar
28: concrete

Claims (5)

Constructed in a line along the ground boundary line, a pair of order grouting groove 111 having a predetermined eccentric distance (e) to the rear center line (CL) passing through the center of the cross section is formed on the outer peripheral surface and hollow 112 inside A plurality of PHC files 10 with; And
The longitudinal direction of the pair of base plates 21a and 21b and the base plates 21a and 21b which are arranged in the direction crossing the PHC pile 10 on the upper surfaces of the PHC piles 10 in parallel with the interval therebetween. The upper part of the abdominal reinforcement 22 is installed in parallel with the plurality of abdominal reinforcement 22, the base plate 21a, 21b coupled to protrude perpendicularly to the base plate 21a (21b) at a predetermined distance along the The upper reinforcing bar 23, which is connected to each other, the upper reinforcing bar 23 is installed in parallel with the pair of intermediate reinforcing bars 24a, 24b connecting the sides of the abdominal reinforcement 22, each of the PHC pile 10 Reinforcement comprising a plurality of vertical bars 26 inserted into the hollow 112 and forming a cylindrical shape and spiral bars 27 surrounding the vertical bars 26 inserted into the hollow and forming a cylindrical shape of each PHC pile. And concrete 28 that is poured into the top and hollow of each PHC pile 10 to accommodate the reinforcement therein. A wall made of PHC piles, characterized in that it comprises a stress shear beam 20 made. The method according to claim 1,
Abdominal reinforcement (22) is a wall made of PHC pile, characterized in that the inverted V-shaped or c-shaped bent shape having a leg 222. The method according to claim 1,
It further includes a plurality of transverse bars 25 disposed in a direction perpendicular to the longitudinal direction of the intermediate bars 24a and 24b and coupled to the abdominal bars 22 to fix the positions of the intermediate bars 24a and 24b. A wall made of PHC piles, characterized in that. PHC pile having a pair of order grouting grooves 111 having a predetermined eccentric distance e rearward with respect to the center line cl passing through the center of the cross section along the ground boundary line and having a hollow 112 therein. Constructing (10) in a line in the ground;
Arranging the tofu of each PHC file (10);
The reinforcement according to any one of claims 1 to 3, wherein a plurality of vertical rebars 26 and a spiral reinforcing bar 27 are assembled so that a cylindrical rebar network is inserted into the hollow 112 of each PHC pile 10, The truss-shaped rebar assembly constructed by assembling a pair of base plates 21a and 21b, a plurality of abdominal reinforcing bars 22, an upper reinforcing bar 23, and a pair of intermediate reinforcing bars 24a and 24b is a PHC pile ( Installing so as to be located on the upper surface of 10); And
PHC pile, comprising the step of installing the formwork and the concrete 28 is embedded so that the reinforcement according to any one of claims 1 to 3 is embedded and filled in the hollow 112 of the PHC pile 10 Construction method of the wall consisting of. The method according to claim 4,
After the step of constructing the PHC pile (10) construction method of the earth wall wall consisting of a PHC pile, characterized in that it further comprises the step of injecting a grout agent into the order grouting groove (111).

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