KR102578665B1 - Concrete Reinforcing Method Using Reaction Anchor - Google Patents

Abstract

In order to reinforce the existing foundation, the present invention excavates the lower part of the existing foundation, inserts a micropile, installs a reaction anchor on the upper part of the existing foundation, and preloads the reaction anchor to the required load on the micropile as a reaction force to meet the added load. A reaction anchor that can reduce the load sharing ratio of the existing foundation structure and facilitates wire loading of the micro pile using a reaction anchor without installing a separate wire loading device, while also allowing the micro pile to be anchored using the reaction anchor. This is about the existing foundation reinforcement method using .
A preferred embodiment of the present invention includes the steps of (a) forming a through hole 11 by drilling a hole vertically through the existing foundation; (b) forming an enlarged excavation groove by expanding and excavating from the bottom of the through hole to a certain depth; (c) forming a drill hole by drilling soil to a certain depth from the bottom of the enlarged excavation groove; (d) forming a reinforcing bar network in the micropile at a certain height and inserting the micropile into the drilling hole through the through hole so that the reinforcing bar network is located in the enlarged excavation groove; (e) Grouting and curing the drilled hole with grout material; (f) installing a reaction anchor on the outside of the through hole at the top of the existing foundation so that it protrudes to the top of the existing foundation, and installing a support plate on the top of the reaction anchor so as to be located on the top of the micropile; (g) connecting a hydraulic press to the upper part of the micropile and operating the hydraulic press with the support plate as a reaction force to load the micropile up to the required load; (h) Grouting and curing the enlarged excavation groove and through hole with grout material; (i) installing a fixing plate on the top of the micro pile and the reaction anchor to fix it.

Description

Existing foundation reinforcement method using reaction anchor {Concrete Reinforcing Method Using Reaction Anchor}

The present invention relates to a method of reinforcing an existing foundation using a reaction anchor. More specifically, to reinforce the existing foundation, the lower part of the existing foundation is excavated, a micro pile is inserted, a reaction anchor is installed on the upper part of the existing foundation, and the reaction anchor is installed. The stability of the existing foundation can be secured by reducing the load sharing ratio of the existing foundation structure for the added load by preloading the micropile up to the required load as a reaction force, and it is possible to reduce the settlement of the entire foundation structure, so separate wire loading is possible. This relates to an existing foundation reinforcement method using a reaction anchor that facilitates wire loading of the micropile using the reaction anchor without installing a device and at the same time allows the micropile to be anchored using the reaction anchor.

When the upper load increases due to expansion or change of use of a building, micropiles are widely used to reinforce the foundation concrete installed on the ground.

In the conventional technology, the micropile top fixation method forms a wide drilled hole to install the micropile, resulting in a large cross-sectional loss of the basic concrete, and as the reinforced concrete is combined with the basic concrete, a pile punching shear occurs at the joint area. ) phenomenon is prone to occur, and there is a problem in that it is not easy to fix the reinforcing bars to the foundation concrete inside the drilled hole.

In particular, due to technical problems in vertical extension remodeling of apartments, when the internal strength of the existing foundation and piles due to expansion is insufficient, the foundation and piles are expanded. However, at this time, the expanded foundation and piles constructed afterward had a mechanical problem in that they could not share and receive the existing load. Therefore, micro piles, etc. were constructed and wire loading was done using a separate wire loading device. However, this is difficult and expensive to construct because a separate wire loading device must be installed on the existing foundation and removed again after going through the wire loading process. There were increasing problems.

The technology behind the present invention includes Patent Publication No. 2014-0017381, “Method for reinforcing basic structures using micropiles” (Patent Document 1). In the background technology, a small-diameter drill hole (12b) is formed from the upper surface to the lower surface of the reinforced portion of the basic concrete (10) so that the micro pile can be installed; To enable the installation of a concrete bulb supporting the lower surface of the foundation concrete 10 at a predetermined width, the width is enlarged from the small diameter drill hole 12b at the bottom of the foundation concrete 10 to allow the ground to a predetermined depth. Forming a large-diameter drilling hole (12a) in (24); Installing a hollow circular casing (23) at a predetermined depth in the ground at the bottom of the large-diameter drilling hole (12a) so that the micro pile (22) can be installed; A lock nut 21, a base plate 20, and a lock nut 21 are sequentially fastened to the micro pile 22 having male threads formed on the outer peripheral surface, and the micro pile 22 is installed in the casing 23; and filling the small-diameter and large-diameter drilling holes with reinforced concrete (11). We propose a 'reinforcement method of a basic structure using micropiles' comprising:

However, the above background technology is difficult to form a large-diameter drilling hole (12a) in the lower part of the basic concrete (10) and does not provide an appropriate method, and the base plate (20) is inserted through the small-diameter drilling hole (12b). There was a problem where it could not be concluded.

Patent Publication No. 2014-0017381 “Method for reinforcing basic structures using micro piles”

The present invention is intended to solve the above problems, and is an existing foundation that can be easily preloaded without installing a separate preloading device after excavating the lower part of the existing foundation and constructing micropiles to reinforce the existing foundation. The purpose is to provide a reinforcement method.

The present invention includes the steps of (a) forming a through hole by drilling vertically through the existing foundation; (b) forming an enlarged excavation groove by expanding and excavating from the bottom of the through hole to a certain depth; (c) forming a drill hole by drilling soil to a certain depth from the bottom of the enlarged excavation groove; (d) forming a reinforcing bar network in the micropile at a certain height and inserting the micropile into the drilling hole through the through hole so that the reinforcing bar network is located in the enlarged excavation groove; (e) Grouting and curing the drilled hole with grout material; (f) installing a reaction anchor on the outside of the through hole at the top of the existing foundation so that it protrudes to the top of the existing foundation, and installing a support plate on the top of the reaction anchor so as to be located on the top of the micropile; (g) connecting a hydraulic press to the upper part of the micropile and operating the hydraulic press with the support plate as a reaction force to load the micropile up to the required load; (h) Grouting and curing the enlarged excavation groove and through hole with grout material; The aim is to provide an existing foundation reinforcement method using a reaction anchor, which includes the step of installing and anchoring a fixing plate on the top of the micro pile and the reaction anchor.

In addition, in step (b), an expanded excavation equipment including a rod of a certain length, an excavation head portion configured to be eccentric to one side at the lower end of the rod, and a plurality of excavation bits arranged on the outer surface of the excavation head portion is used. , We intend to provide a method of reinforcing an existing foundation using a reaction anchor, which is characterized in that the excavation head is located at the bottom of the existing foundation through a through hole, and then the lower surface of the existing foundation is expanded and excavated to form an expanded excavation groove.

Additionally, in step (d), the reinforcing bar network is configured to surround a horizontal plate-shaped fixing plate, a plurality of lateral roots configured to protrude upwardly to the outside of the central portion of the fixing plate, and a plurality of lateral roots. It is intended to provide an existing foundation reinforcement method using a reaction anchor, which is composed of reinforcing bars and is configured so that the micropile penetrates the central part of the fixing plate and is coupled at a certain height.

In addition, in step (d), the outer bars of the reinforcing bar network are configured to spread outward from the bottom to the top, and the auxiliary bars are wound around the outer bars in a spiral shape and compressed so that the upper ends of the outer bars face vertically upward. We aim to provide an existing foundation reinforcement method using a reaction anchor, which is configured to fix and dismantle the fixation in the enlarged excavation groove so that the lateral root spreads outward.

In addition, in step (i), the fixing plate is a reaction anchor, characterized in that the upper part of the existing foundation is seated by forming a groove equal to the thickness of the anchoring plate so that the upper surface of the existing foundation matches the upper surface of the anchoring plate. We would like to provide existing foundation reinforcement methods using this method.

The existing foundation reinforcement method using the reaction anchor of the present invention involves excavating the lower part of the existing foundation and inserting a micropile to reinforce the existing foundation, then installing the reaction anchor on the upper part of the existing foundation, and applying the required load to the micropile using the reaction anchor as a reaction force. It is possible to secure the stability of the existing foundation by reducing the load sharing ratio of the existing foundation structure for the added load by pre-loading up to the maximum, and it is possible to reduce the settlement of the entire foundation structure, so reaction anchors can be installed without the installation of a separate pre-loading device. It has the very useful effect of facilitating wire loading on the micro pile and at the same time allowing the micro pile to be anchored using the reaction anchor.

The following drawings attached to this specification illustrate preferred embodiments of the present invention, and serve to further understand the technical idea of the present invention along with the detailed description of the invention. Therefore, the present invention is limited to the matters described in the attached drawings. It should not be interpreted as limited.
Figures 1 to 9 sequentially show the existing foundation reinforcement method using the reaction anchor of the present invention.

Below, the present invention will be described in detail with reference to embodiments shown in the attached drawings, but the presented embodiments are illustrative for a clear understanding of the present invention, and the present invention is not limited thereto.

Hereinafter, the technical configuration of the present invention will be described in detail according to preferred embodiments.

Figures 1 to 9 sequentially show the existing foundation reinforcement method using the reaction anchor of the present invention.

The existing foundation reinforcement method using the reaction anchor of the present invention will be described in detail in order with reference to the drawings as follows.

First, as shown in FIG. 1, a through hole 11 is formed by drilling vertically through the existing foundation 10 (a).

The through hole 11 is drilled using various known drilling equipment 110, and the cross-sectional shape of the through hole 11 is circular.

Thereafter, as shown in FIG. 2, the bottom of the through hole 11 is enlarged and excavated to a certain depth to form an enlarged excavation groove 12 (b).

By forming an enlarged excavation groove 12 that is larger than the cross section of the through hole 11 penetrating the existing foundation 10 in the lower part of the existing foundation 10, stability is secured by minimizing damage to the existing foundation 10. While this can be done, it is possible to insert a reinforcing bar network 30, which will be described later, so that it can be anchored at the lower part of the existing foundation 10.

In this way, in order to form the enlarged enlarged excavation groove 12 on the lower surface of the existing foundation 10, various known enlarged excavation equipment can be used. In particular, as shown, the enlarged excavation equipment 170 A rod 171 of a certain length, an excavation head 172 configured to be eccentric to one side at the lower end of the rod 171, and an excavation bit 173 arranged in plural numbers on the outer surface of the excavation head 172. ), and after entering the through-hole 11 so that the excavation head part 172 is located at the lower part of the existing foundation 10, the lower surface of the existing foundation 10 is expanded and excavated to enlarge the excavation groove ( 12) can be formed.

The enlarged excavation equipment 170 configured in this way allows the excavation head portion 172 to rotate around the rod 171 when the rod 171 rotates, and therefore, the rod 171 of the enlarged excavation equipment 170 After fastening various known excavation equipment, the excavation head part 172 is inserted into the through hole 11 of the existing foundation 10 and positioned at the lower part of the existing foundation 10, and then the rod 171 penetrates. When the rod 171 is rotated by operating the excavation equipment after moving to a position in contact with or close to the inner wall of one side of the hole 11, the excavation head 172 rotates and has an enlarged cross section than the through hole 11. An enlarged excavation groove 12 is formed.

Thereafter, as shown in FIG. 3, the soil is drilled to a certain depth from the bottom of the enlarged excavation groove 12 to form a drill hole 13 (c).

Using separate excavation equipment (80), the soil is drilled to a certain depth from the bottom of the enlarged excavation groove (12) to form a drill hole (13). At this time, the size of the cross section of the drill hole (13) is the through hole. It should be made the same or similar to the size of the cross section in (11).

Thereafter, as shown in FIGS. 4 and 5, the micro pile 20 is installed in the drill hole 13 through the through hole 11 (d).

At this time, the reinforcing bar network 30 is configured at a certain height in the micro pile 20, and the reinforcing bar network 30 is located in the enlarged excavation groove 12, so that the reinforcing bar network 30 is installed at the lower part of the existing foundation 10. ) can be easily fixed to respond to punching shear, etc.

The reinforcing bar network 30 is inserted into the micro pile 20 and can be fixed at a certain height of the micro pile 20 using a fixing means 21 such as a nut to facilitate height adjustment, and such a reinforcing bar network ( 30) can be made of various shapes.

In particular, the reinforcing bar network 30 includes a plate-shaped fixing plate 31 so that the micropile 20 can be easily inserted and installed, and a plurality of plates configured to protrude upward to the outside of the central portion of the fixing plate 31. It is made of an lateral root 32 and an auxiliary reinforcing bar 33 configured to surround the plurality of lateral muscles 32, and the micropile 20 penetrates the central part of the fixing plate 31 to a certain height. It is fixed using fixing means 21, etc.

At this time, a through hole (not shown) for penetration of the micropile 20 may be formed in the fixing plate 31 to facilitate installation, and a surface on which the lateral root 32 is installed may be provided.

The lateral muscle 32 is arranged radially at a certain distance from the center of the fixing plate 31, and the lower end is welded or penetrated into the fixing plate 31 so as to protrude upward and is fixed by a separate coupling means such as a nut. The lateral root 32 is allowed to protrude from the top of the plate 31. In addition, such a plurality of outer muscles 32 are formed integrally with auxiliary reinforcing bars 33 to surround the outside of the plurality of outer muscles 32.

In this way, the reinforcement network 30 is formed with the outer bars 32 and auxiliary reinforcement bars 33 on the upper part of the fixing plate 31, so that the reinforcement network 30 is inserted into the enlarged excavation groove 12 and grouted with grout material. When this is done, it is possible to prevent the grout material from being cut off by the fixing plate 31 and make it easy to fix.

In particular, the enlarged excavation groove 12 has a cross section larger than that of the through hole 11, so that it can stably support the lower part of the existing foundation 10 and effectively respond to punching shear. To this end, the reinforcing bar network 30 is used. The itself can also have a cross section larger than that of the through hole (!1).

However, when the reinforcing bar network 30 has a cross section larger than that of the through hole 11, insertion of the reinforcing bar network 30 through the through hole 11 is impossible. Therefore, in the present invention, as in FIGS. 4 and 5 Likewise, the outer bars 32 of the reinforcing bar network 30 are configured to spread outward from the bottom to the top, and the auxiliary bars 33 are spirally wound around the outer bars 32 to form the outer bars 32. Compress and secure the upper part so that it faces vertically upward.

In this way, when the auxiliary reinforcing bar 33 is wound in a spiral shape and the upper part is tightened, the upper end of the outer bar 32 is gathered to the central part and reaches a vertical state. At this time, it is tied and fixed with a separate fixing string (not shown), etc., as shown in Figure 4b. It is made in the same state as and inserted through the through hole 11, and the fixing strap (not shown) that fixed the outer bars 32 of the reinforcing bar network 30 in the enlarged excavation groove 12 in a gathered state is removed and fixed. When dismantled, the upper end of the lateral root 32 opens radially to restore it to its original state, so that the cross-section becomes larger than the size of the through hole 11, so that it can be anchored to the lower part of the existing foundation 10.

Thereafter, as shown in FIG. 6, after grouting and curing the drilled hole 13 with the grout material 90 (e), the existing foundation 10 is placed on the outside of the through hole 11 from the top of the existing foundation 10. Install the reaction anchor (40) so that it protrudes to the top (f).

After grouting and curing the grout material (90) only in the drilling hole (13), excluding the enlarged excavation groove (12), a reaction anchor (40) is installed on the upper part of the existing foundation (10). The reaction anchor (40) is a micro It is installed on the pile 20 to use it as a reaction force for wire loading using the hydraulic machine 50.

For this purpose, a plurality of reaction anchors 40 are installed symmetrically on the main surface of the through hole 11 at the top of the existing foundation 10, and are located at the top of the micro pile 20 at the top of the reaction anchor 40. The support plate 41 is fixed and installed so as to do so.

Thereafter, as shown in FIGS. 8 and 9, the hydraulic press 50 is connected to the upper part of the micro pile 20, and the hydraulic press 50 is operated using the support plate 41 as a reaction force to load the micro pile 20 up to the required load. Do so (g).

At this time, after pressurizing the required load with the hydraulic press (50), the hydraulic press (50) is maintained as is, and if no additional settlement occurs, the enlarged excavation groove (12) and through hole (11) are grouted with grout material (60) and cured. Thus, the reinforcing bar network 30 is established at the lower part of the existing foundation 10 (h).

Finally, as shown in Figure 9, a fixing plate 70 is installed on the top of the micro pile 20 and the reaction anchor 40 to organize and fix the head of the micro pile 20 (i).

In this way, the reaction anchor 40 is used as a reaction force of the hydraulic machine 50 and at the same time serves as a anchoring anchor for anchoring the end of the micro pile 20 without removing the reaction anchor 40 after loading. will be.

At this time, the fixing plate 70 is seated on the upper part of the existing foundation 10 by forming a groove equal to the thickness of the fixing plate 70 so that the upper surface of the existing foundation 10 and the upper surface of the fixing plate 70 are aligned. It may be possible to do so, and it may be fixed using a separate fixing means (71).

The existing foundation reinforcement method using the reaction anchor of the present invention as described above involves excavating the lower part of the existing foundation and inserting a micropile to reinforce the existing foundation, then installing the reaction anchor on the upper part of the existing foundation, and using the reaction anchor as the reaction force to build the micropile. The stability of the existing foundation can be secured by reducing the load sharing ratio of the existing foundation structure for the added load by preloading up to the required load, and it is possible to reduce the settlement of the entire foundation structure without installing a separate preloading device. There is a very useful effect of using a reaction anchor to facilitate wire loading on a micro pile and at the same time allowing the micro pile to be anchored using a reaction anchor.

So far, the present invention has been described in detail with reference to the presented embodiments, but those skilled in the art can make various variations and modifications without departing from the technical spirit of the present invention with reference to the presented embodiments. will be. The present invention is not limited by such variations and modifications, but is limited by the claims appended below.

10: Existing foundation
11: Through hole
20: micro file
30: rebar mesh
40: reaction anchor
41: support plate
50: hydraulic machine
70: Expanded excavation equipment

Claims (5)

(a) forming a through hole (11) by drilling a hole vertically through the existing foundation (10);
(b) forming an enlarged excavation groove 12 by excavating the bottom of the through hole 11 to a certain depth;
(c) forming a drill hole (13) by drilling soil from the bottom of the enlarged excavation groove (12) to a certain depth;
(d) Constructing a reinforcing bar network 30 in the micro pile 20 at a certain height, drilling the micro pile 20 through the through hole 11 so that the reinforcing bar network 30 is located in the enlarged excavation groove 12. Inserting into the hole 13;
(e) grouting and curing the drilled hole (13) with grout material (90);
(f) A reaction anchor 40 is installed on the outside of the through hole 11 at the top of the existing foundation 10 so as to protrude to the top of the existing foundation 10, and the reaction anchor is positioned at the top of the micropile 20. Installing the support plate 41 on the upper part of (40);
(g) connecting the hydraulic press 50 to the upper part of the micro pile 20 and operating the hydraulic press 50 as a reaction force to load the micro pile 20 up to the required load;
(h) Grouting and curing the enlarged excavation groove (12) and the through hole (11) with grout material (60);
(i) Installing and anchoring a fixing plate (70) on the top of the micro pile (20) and the reaction anchor (40). An existing foundation reinforcement method using a reaction anchor, comprising: In claim 1,
In step (b),
A rod 171 of a certain length, an excavation head 172 configured to be eccentric to one side at the lower end of the rod 171, and an excavation bit 173 arranged in a plurality on the outer surface of the excavation head 172. Expanded excavation equipment (170) including,
The excavation head part 172 is characterized by entering the through hole 11 so that it is located at the lower part of the existing foundation 10 and then excavating the lower surface of the existing foundation 10 to form an enlarged excavation groove 12. Existing foundation reinforcement method using reaction anchors. In claim 1,
In step (d),
The reinforcing bar network 30 includes a horizontal plate-shaped fixing plate 31, a plurality of lateral roots 32 configured to protrude upward to the outside of the central portion of the fixing plate 31, and a plurality of lateral roots 32. It consists of auxiliary reinforcing bars (33) configured to surround the circumference,
An existing foundation reinforcement method using a reaction anchor, characterized in that the micropile (20) penetrates the central part of the fixing plate (31) and is coupled to a certain height. In claim 3,
In step (d),
The outer bars 32 of the reinforcing bar network 30 are configured to spread outward from the bottom to the top, and the auxiliary bars 33 are spirally wound around the outer bars 32 so that the upper ends of the outer bars 32 are formed. Compressed and fixed to face vertically upward,
An existing foundation reinforcement method using a reaction anchor, characterized in that the outer root (32) is configured to spread outward by dismantling the fixation in the enlarged excavation groove (12). In claim 1,
In step (i),
The fixing plate 70 is seated on the upper part of the existing foundation 10 by forming a groove equal to the thickness of the fixing plate 70 so that the upper surface of the existing foundation 10 matches the upper surface of the fixing plate 70. An existing foundation reinforcement method using a reaction anchor, characterized in that:

Images