KR20100078632A - Construction method of combined micro-pile with existing structure - Google Patents

Abstract

PURPOSE: A construction method for coupling a micro-pile with an existing structure is provided to safely transfer a load applied to a building by changing the stress direction of the load. CONSTITUTION: A construction method for coupling a micro-pile with an existing structure is as follows. A hole for a micro-pile is drilled in foundation concrete(101) and foundation ground(102). The hole drilled in the foundation ground is filled with cement milk or mortar. A part of the hole drilled in the foundation concrete is reamed in a circumference direction. The hole drilled in the foundation concrete is filled with cement milk or mortar.

Description

Construction method of Combined micro-pile with existing structure

The present invention relates to a method of joining a micro pile with an existing structure, and more particularly, to add a basic reinforcement according to occurrence of additional load due to settlement, flotation or extension of an existing structure, which is used for ground reinforcement in civil engineering and construction. The present invention relates to a method of combining micro piles with existing structures in the construction of micro piles that can be constructed in general.

A micro pile generally refers to a micropile formed in the ground and a pulley or support force generated in the structure by the main surface ground friction, or a small diameter pile (generally 300 mm or less in diameter) that can simultaneously cope. As it is used, it has the advantage of supporting large loads compared to forming small-diameter piles by using small equipment, so it is mainly applied to a condition where entry of large equipment is difficult due to space constraints or site conditions. .

Basically drills the foundation ground and inserts the core rod into the core, and the space between the core and the drill hole inserted in the drill hole is cured by injecting or filling cement milk or mortar. To form.

And the upper part of the micro pile is installed a pressure plate located in the foundation concrete, and then cast the foundation concrete to play a role to transfer the load by integrating with the upper structure.

However, in the case of the existing structure, the concrete is already poured and cured, so that it has an anchor bolt structure, a shear bolt reinforcement structure, and a multi-plate structure (Publication Patent No. 10-2008-0008294) for combining the micro pile and the existing structure. It is disclosed as a prior art.

This structure is incorporated in the foundation concrete and plays a role in transferring the load of the superstructure to the foundation ground.

Anchor bolt structure and shear bolt reinforcement structure reinforces the pulling stress or compressive stress received by the upper structure by using anchor bolt or shear bolt, and has the advantage as a structure that depends on the reinforcement force by anchor bolt or shear bolt. Installation of anchor bolts and shear bolts for joining existing structures of micro piles reinforced during extension of buildings is problematic in that the foundation concrete needs to be demolished and restored in a wide and deep manner, thus reducing work efficiency.

The multi-plate structure is disclosed to improve the construction efficiency of the above-described anchor bolt structure and shear bolt structure, and distributes the load of the superstructure by the friction force between the shearing and grout and the grouting material and the cut surface of the perforated foundation concrete. As a structure to increase the workability, but the head structure of the micro pile has a complex disadvantage of installing more than one stage of the composite structure of the lower lock nut, shearing, spacer and the upper lock nut.

An object of the present invention for solving the above-mentioned conventional problems is to simplify the construction of the existing reinforcement of the existing structure, and to change the transfer stress direction of the load (pulling stress and compressive stress) received by the foundation structure to enable safe load transfer To propose a micro pile combined construction method with existing structures.

The construction method of the reinforcement micropile according to the present invention for solving the above problems includes (a) drilling a hole for inserting the micropile into the foundation concrete; (b) drilling holes for inserting micro piles into the foundation ground; (c) inserting the micro pile into the holes drilled in (a) and (b); (d) grouting or filling cement milk or mortar to the foundation ground; (e) expanding a portion of the perforated hole in the base concrete in the circumferential direction; (f) fastening a nut and filling the hole of the foundation concrete with cement milk or mortar.

In addition, the construction method of the reinforcement micro pile according to the present invention, (a) a step of drilling a hole for inserting the micro pile into the foundation concrete; (b) drilling holes for inserting micro piles into the foundation ground; (c) inserting the micro pile into the holes drilled in (a) and (b); (d) grouting or filling cement milk or mortar up to the foundation ground; (e) fastening a nut to the micropile; (f) expanding a portion of the perforated hole in the base concrete in the circumferential direction and filling the unfilled portion with cement milk or mortar.

Here, it is preferable that the cross section of the said dilation part is triangular shape, and the said dilation part is one or more.

Here, the nut has a trapezoidal cross section, and the nut of the trapezoidal shape is preferably fastened by being positioned in a trapezoidal, inverted trapezoidal or forward / historical trapezoidal combination.

Here, the nut is to change the transfer stress direction of the load according to the compressive stress, the pull stress or the compression / pull stress received by the structure, in the case of being subjected to the trapezoidal, the pull stress when the load is subjected to the compressive stress In the case of both trapezoidal and compressive / pull stress, it is preferable to be positioned and fastened in a forward / reverse trapezoidal coupling form.

According to the above-described configuration of the present invention, the micro pile with the existing structure that enables safe load transfer by converting the transfer stress direction of the load (pulling stress and compressive stress) that the building receives while being easy to construct when reinforcing the existing structure. It enables the combined construction method.

Hereinafter, with reference to the accompanying drawings looks at the construction method and the effect of the micro pile combined with the existing structure according to the present invention.

The micro pile used in the present invention generally refers to a file having a small diameter. When using the micro pile, the micro pile has a merit of supporting a large load compared to forming a file having a small diameter using small equipment. Therefore, it is mainly applied to the condition that entry of large equipment is difficult due to space constraints or site conditions. In particular, in the construction of a micropile that can be additionally constructed for reinforcement due to additional load generation due to settlement or flotation or extension of the existing structure described in the present invention, a construction useful for joining a micropile with an existing structure. Specifies the method.

Looking at the configuration of the first to fourth embodiments according to Figures 1 to 3, the foundation concrete (101, 201, 301) and the foundation ground (102, 202, 302) is formed under the building.

The foundation grounds 102, 202, and 302 are divided into a soft layer made of clay, sand, and the like and a support layer made of rock, but are not separately specified in the present invention.

The construction of the completed micro pile structure system includes: the foundation concrete (101, 201, 301) layer and the foundation ground (102, 202, 302), the drill hole into which the micro pile is inserted, and the micro pile (103, 203, 303). , Fills 106, 206, 306, dilatations 107, 207, 307 and nuts 108, 208, 308.

The micro pile construction method having such a structure will be described below with reference to the first and fourth embodiments.

[First of Micro Pile Coupling with Existing Structures Example ]

Figure 1a shows a process diagram of the construction method of the reinforcing micro pile according to the first embodiment of the present invention.

First, a process (A) of drilling a hole for inserting a micro pile into a foundation concrete and a process (B) of drilling a hole for inserting a micro pile into a foundation ground are performed.

Thereafter, the micro pile 103 is inserted into the drilling hole made in the steps (A) and (B) and then installed (C). In this case, the spacer 104 may be placed in the middle of the micro pile 103 so that the micro pile 103 has a constant distance between the center of the drilling hole, that is, the inner circumferential surface of the drilling hole and the micro pile 103. In this case, the plurality of micro piles 103 may be connected and used by the coupler 105.

When the micro pile 103 is positioned in step (C), a grouting step (D) of filling cement milk or mortar is performed to the height of the foundation ground 102.

After the grouting process is performed, a process (E) of expanding a part of the base concrete 101 to form an expansion hole is performed.

The cross section of the dilating part 107 is triangular in shape, and expands so that the extending surface becomes narrower as it goes out of the circumferential surface along the circumferential surface of the drilling hole. It may extend from 30 degrees to 60 degrees.

After the expansion is completed, the nut 108 is fastened and the process (F) of filling the boring hole of the foundation concrete 101 with cement milk or mortar finishes all processes.

The structure of the nut 108 used in the step (F) is trapezoidal in cross section, and in the first embodiment of the present invention, the nut 108 is positioned and fastened in a trapezoidal shape, The angle of the inclined side is formed almost similar to the slope of the cross section of the dilator 107.

The micro pile construction structure according to the first embodiment of the present invention enters the basic concrete 101 and plays a role of transferring the load of the upper structure to the foundation ground.

In particular, it is a suitable construction method when the load received by the upper structure is a structure mainly subjected to compressive stress, and by this structure, the transfer stress direction of the compressive stress load is changed in the direction of the arrow of (F) shown in FIG. You can increase the file's functionality more efficiently.

[2nd of micro pile joining construction with existing structures Example ]

Figure 2a is a process diagram showing a second embodiment of the micro pile bonding construction with the existing structure of the present invention. The second embodiment is a step in which the steps (E) and (F) of the first embodiment described above are changed, and the nut 108 is first tightened in the step (E), and the dilator 107 is closed in the (F) step. After expansion, the process is filled with milk or mortar, and the remaining processes and conditions are the same as in the first embodiment.

[Third of micro pile joining construction with existing structure Example ]

Figure 2 shows a process diagram of the construction method of the reinforcing micro pile according to the third embodiment of the present invention.

First, a process (A) of drilling a hole for inserting a micro pile into a foundation concrete and a process (B) of drilling a hole for inserting a micro pile into a foundation ground are performed.

Thereafter, the micro pile 203 is inserted into the drilling hole made in the steps (A) and (B) and then installed (C).

When the micro pile 203 is positioned in the step (C), a grouting step (D) is performed in which cement milk or mortar is filled up to the height of the foundation ground 202.

After the grouting process is performed, a process (E) of expanding a part of the foundation concrete 201 to form an expansion hole is performed.

The cross section of the dilation portion 207 is triangular in shape and extends so that the extending surface becomes narrower as it goes out of the circumferential surface along the circumferential surface of the drilling hole, and preferably, the extended cross section is a vertically symmetrical or asymmetrical structure, and one surface is approximately 30 It may extend from an angle to 60 degrees.

After the expansion is completed, the nut 208 is fastened and all the processes are completed through the process (F) of filling the boring hole of the foundation concrete 201 with cement milk or mortar.

Here, unlike the first embodiment of the present invention, the nut 208 is positioned and fastened in an inverted trapezoid shape.

That is, the third embodiment is a construction method suitable when the load received by the superstructure is mainly a structure that receives the draw stress, and by this structure the transfer stress of the pull stress load in the direction of the arrow (F) shown in FIG. By changing the direction, the function of the reinforcement micro file can be improved more efficiently.

[4th of micro pile joining construction with existing structures Example ]

Figure 3 shows a process diagram of the construction method of the reinforcing micro pile according to the fourth embodiment of the present invention.

First, a process (A) of drilling a hole for inserting a micro pile into a foundation concrete and a process (B) of drilling a hole for inserting a micro pile into a foundation ground are performed.

Thereafter, the micro pile 303 is inserted into the drilling hole made in the steps (A) and (B) and then installed (C).

When the micro pile 303 is positioned in the step (C), a grouting step (D) is performed in which cement milk or mortar is filled up to the height of the foundation ground 302.

After the grouting process is performed, a process (E) of expanding a part of the foundation concrete 301 to form an expansion hole is performed.

The cross-section of the dilation portion 307 is triangular in shape, and extends so that the extending surface becomes narrower as it goes out of the circumferential surface along the circumferential surface of the drilling hole. It may extend from an angle to 60 degrees.

After the expansion is completed, the nut 308 is fastened and all the processes are completed through the process (F) of filling the boring hole of the foundation concrete 301 with cement milk or mortar.

Here, unlike the first and second embodiments of the present invention, the nut 308 is fastened by positioning and combining a trapezoidal and an inverted trapezoidal shape.

That is, the fourth embodiment is a suitable construction method when the load received by the upper structure is a structure that receives both the compressive stress and the drawing stress, and the compressive stress and the stress in the direction of the arrow (F) shown in FIG. By changing the transfer stress direction of the drawn stress load, the function of the reinforcement micropile can be improved more efficiently.

FIG. 4 shows another embodiment of the first embodiment, FIG. 5 shows another embodiment of the second embodiment, FIG. 6 shows another embodiment of the first embodiment, and FIG. 5 shows the first embodiment. Another embodiment of the second embodiment is shown.

FIG. 4 shows another embodiment of the first embodiment, in which a plurality of expansion portions 407a and 407b are formed by vertically expanding the expansion portions in the foundation concrete 401 layer when the upper structure receives a large load of compressive stress. In addition, the plurality of nuts 408a and 408b are assembled and cement grouted, respectively, in a trapezoidal position corresponding to the plurality of expansion portions 407a and 407b. By this structure, it is possible to sufficiently perform the role of reinforcing support of the upper structure by converting the transfer stress direction in response to the compressive stress received by the upper structure.

FIG. 5 shows another embodiment of the second embodiment, in which a plurality of expansion portions 507a and 507b are formed with the expansion portions up and down equally up and down on the foundation concrete 501 layer when the upper structure is subjected to a large load of drawing stress. In addition, the plurality of nuts 508a and 508b are assembled and cement grouted at positions corresponding to the plurality of expansion portions 507a and 507b in the inverted trapezoidal shape. By this structure, it is possible to sufficiently perform the role of reinforcing support of the upper structure by converting the transfer stress direction in response to the drawn stress received by the upper structure.

FIG. 6 is an embodiment having a dilation portion 607 between the foundation concrete 601 and the foundation ground 602, and FIG. 7 is an embodiment having the dilation portion 707 at the upper end of the foundation concrete 701. In addition, the expansion portion may be formed in various forms, and the fastening position of the nut may be variously changed according to the position and shape of the expansion portion.

Although the preferred embodiments of the present invention have been described above with reference to the accompanying drawings, the above-described technical configuration of the present invention may be embodied by those skilled in the art to which the present invention pertains without changing its technical spirit or essential features of the present invention. It will be appreciated that the present invention may be practiced as. Therefore, the above-described embodiments are to be understood as illustrative and not restrictive in all respects, and the scope of the present invention is indicated by the appended claims rather than the detailed description, and the meaning and scope of the claims and All changes or modifications derived from the equivalent concept should be interpreted as being included in the scope of the present invention.

Figure 1a shows a process diagram of the construction method of the reinforcing micro pile according to the first embodiment of the present invention.

Figure 1b shows a process diagram of the construction method of the reinforcing micro pile according to the second embodiment of the present invention.

Figure 2 shows a process diagram of the construction method of the reinforcing micro pile according to the third embodiment of the present invention.

Figure 3 shows a process diagram of the construction method of the reinforcing micro pile according to the fourth embodiment of the present invention.

4 shows another embodiment of the first embodiment.

5 shows another embodiment of the second embodiment.

6 shows yet another embodiment of the first embodiment.

7 shows another embodiment of the second embodiment.

Claims (5)

(a) drilling a hole for inserting a micro pile into the foundation concrete; (b) drilling holes for inserting micro piles into the foundation ground; (c) inserting the micro pile into the holes drilled in (a) and (b); (d) grouting or filling cement milk or mortar up to the foundation ground; (e) expanding a portion of the perforated hole in the base concrete in the circumferential direction; and (f) fastening a nut and filling the hole of the base concrete with cement milk or mortar. (a) drilling a hole for inserting a micro pile into the foundation concrete; (b) drilling holes for inserting micro piles into the foundation ground; (c) inserting the micro pile into the holes drilled in (a) and (b); (d) grouting cement milk or mortar to less than the base ground; (e) fastening a nut to the micropile; and (f) expanding a portion of the perforated hole in the foundation concrete in the circumferential direction and filling the unfilled portion with cement milk or mortar. The method according to claim 1 or 2, Cross section of the expansion portion is a triangular shape, the expansion portion is one or more, micro pile coupling construction method with an existing structure. The method of claim 3, The nut has a trapezoidal cross section, and the trapezoidal nut is located in a trapezoidal, inverted trapezoidal or forward / historical trapezoidal coupling form, and a micro pile coupling construction method with an existing structure. The method of claim 4, wherein The nut is a trapezoid when subjected to a compressive stress, an inverted trapezoid when under a load of the pulled stress, so as to change the direction of the transfer stress of the load according to the compressive stress, the pull stress, or the compression / draw stress that the structure receives. Method of joining micro piles with existing structures, which are positioned and fastened in the form of forward / historical coupling when both compressive and pulling stresses are applied.

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