KR102400508B1 - Construction method of retaining wall installation structure - Google Patents

Abstract

The present invention relates to a construction method of a retaining wall installation structure, which comprises: a first step of excavating a certain depth from the ground to perform excavation, driving a plurality of H beams to be close to the excavated cutting surface, and installing a plurality of earth plates by being coupled between the plurality of H beams to be supported on the cutting surface; a second step of horizontally mounting horizontal beams to connect the plurality of H beams; a third step of driving an anchor through the horizontal beam of the second step and burying the anchor to be inserted into the cutting surface at a certain depth; and a fourth step of injecting and hardening cement paste around the anchor of the cutting surface to fix the anchor. The present invention can prevent the weakening of the ground.

Description

Construction method of retaining wall installation structure

The present invention relates to a construction method of a retaining wall installation structure, and more particularly, a retaining wall installation structure to which a ground anchor is applied, which can stably support a wale (horizontal beam) installed to fix a tension member inserted into the ground. It relates to the construction method of

When excavating the ground to construct the foundation or underground structure of a structure such as a building, a retaining wall is used to prevent the ground on the back of the excavation from collapsing due to earth pressure. This retaining wall is composed of a retaining wall and a supporting structure.

The thumb pile and earth plate construction method is a representative construction method among retaining methods, and is the most applied because of the lowest construction cost. It is composed of a plurality of earth plates to prevent the piles of soil from collapsing toward the front.

In the retaining method, the raker method, which has been used for a long time among supports, has been mainly used in cases where it is difficult to apply a horizontal brace because the site width is more than 50.0m.

Since the H-beam alone cannot resist the earth pressure of the soil behind it, a large number of supporting materials (struts, ground anchors, rakers, etc.) must be used to reinforce it.

A ground anchor is used as an effective method to apply a transverse or vertical binding force and a preceding load to the structure by introducing a high tension force to high-strength steel to anchor the target structure to the ground.

In the ground anchor method, a hole is drilled in the retaining wall instead of a brace in order to fix civil engineering or building structures on the ground, and the grout is filled and hardened together with the insertion of a tension member into the hole, and then a tensile force is introduced into the tension member to support the earth pressure. it's a technique

Ground anchor method is applied to support work of temporary earth wall, permanent anchor earth wall, transmission tower foundation, buoyancy anchor of reinforced underground structure of dam, slope reinforcement, etc.

The anchor body used in the ground anchor method stabilizes the structure from excessive stress, deformation, displacement, etc. occurring in the ground by fixing high-strength tensile members such as PC strands to both the structure and the inside of the ground and applying a prestress at the civil engineering site. make it

According to the prior art, the load supporting part is constructed by drilling a hole to a certain depth into the ground, inserting a steel material, and then injecting and hardening the concrete mortar into the hole.

After that, the end of the steel is connected to the thumb pile so that the supporting force is exerted.

However, in this prior art, there is a risk of weakening the ground because the diameter of the hole must be enlarged and formed deeply in order to secure sufficient bearing capacity of the steel, and since the drilling process of the hole takes a lot of time, there is a problem of cost increase.

Korean Patent Application No. 10-2013-0018222

The present invention has been devised to solve the problems of the prior art, and it is possible to prevent weakening of the ground by making the depth of drilling for the ground shallow. The purpose of this is to provide a construction method for retaining wall installation structures in which concrete mortar is injected into halls and anchorages by forming a field, and steel material is charged so that strong bearing capacity can be exerted.

The above object of the present invention is to perform excavation by excavating to a certain depth from the ground, driving a plurality of H-beams to be close to the excavated cut surface, coupled between the plurality of H-beams to be supported on the cut surface, so that a plurality of Step 1 of installing the earth plate; Step 2 of mounting a horizontal beam horizontally to connect the plurality of H-beams; A third step of inserting an anchor through the horizontal beam of the second step and burying the anchor so that the anchor is inserted to a predetermined depth in the cut surface; Including; step 4 of injecting cement paste around the area where the anchors of the cut surface are embedded, and curing the anchors to fix the anchors; step 4 is to drill the tunnel to a certain depth using a drilling bit for the cut surface The construction of a retaining wall installation structure, characterized in that an extension is formed at the end of the tunnel so that the diameter is expanded, an anchor is inserted up to the tunnel and the extension, and cement paste is injected into the tunnel and the extension method can be achieved.

The punching bit for drilling the tunnel and extension of the fourth step includes a body having a bit blade on the outer surface, a variable blade formed to protrude and retract at the end of the body, and a variable blade to protrude and retract by being formed inside the end of the body. It is characterized in that it includes; a power supply line formed inside the body and connected to the actuator, and a power generator provided outside the body and connected to the power supply line.

According to the present invention, it is possible to prevent weakening of the ground by making the depth of drilling for the ground for installing the ground anchor shallow, but the bearing capacity of the ground anchor can be strengthened, and the length of the tunnel is shortened but a large-diameter extended anchorage is formed By doing this, concrete mortar is injected into the tunnel and anchorage, and a ground anchor is inserted so that strong bearing capacity can be exerted, thereby reducing the length of the tunnel relatively, reducing construction cost and period, and preventing the weakening of the ground. there is

1 is a process flow diagram showing a construction method of a retaining wall installation structure according to the present invention;
2 is a construction drawing showing a retaining wall installation structure according to the present invention;
3 is a view showing a punched bit;
4 is a flowchart showing a process of further installing a steel structure to the retaining wall installation structure according to the present invention;
5 is a flowchart showing the process of installing the deck plate assembly to the steel structure installed in the retaining wall installation structure according to the present invention;
6 is a view showing a cross-sectional structure of a first heat insulating material according to an embodiment of the present invention;
7 is a view showing a cross-sectional structure of a second heat insulating material according to an embodiment of the present invention.

Hereinafter, embodiments will be described in detail with reference to the accompanying drawings. However, since various changes may be made to the embodiments, the scope of the patent application is not limited or limited by these embodiments. It should be understood that all modifications, equivalents and substitutes for the embodiments are included in the scope of the rights.

Specific structural or functional descriptions of the embodiments are disclosed for purposes of illustration only, and may be changed and implemented in various forms. Accordingly, the embodiments are not limited to the specific disclosure form, and the scope of the present specification includes changes, equivalents, or substitutes included in the technical spirit.

Although terms such as first or second may be used to describe various elements, these terms should be interpreted only for the purpose of distinguishing one element from another. For example, a first component may be termed a second component, and similarly, a second component may also be termed a first component.

When a component is referred to as being “connected to” another component, it may be directly connected or connected to the other component, but it should be understood that another component may exist in between.

The terms used in the examples are used for the purpose of description only, and should not be construed as limiting. The singular expression includes the plural expression unless the context clearly dictates otherwise. In this specification, terms such as "comprise" or "have" are intended to designate that a feature, number, step, operation, component, part, or a combination thereof described in the specification exists, but one or more other features It should be understood that this does not preclude the existence or addition of numbers, steps, operations, components, parts, or combinations thereof.

Unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which the embodiment belongs. Terms such as those defined in commonly used dictionaries should be interpreted as having a meaning consistent with the meaning in the context of the related art, and should not be interpreted in an ideal or excessively formal meaning unless explicitly defined in the present application. does not

In addition, in the description with reference to the accompanying drawings, the same components are given the same reference numerals regardless of the reference numerals, and the overlapping description thereof will be omitted. In describing the embodiment, if it is determined that a detailed description of a related known technology may unnecessarily obscure the gist of the embodiment, the detailed description thereof will be omitted.

Advantages and features of the present invention and methods of achieving them will become apparent with reference to the embodiments described below in detail in conjunction with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but will be implemented in a variety of different forms, and only these embodiments allow the disclosure of the present invention to be complete, and common knowledge in the technical field to which the present invention belongs It is provided to fully inform the possessor of the scope of the invention, and the present invention is only defined by the scope of the claims.

In the embodiments of the present invention, unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which the present invention belongs. have meaning Terms such as those defined in a commonly used dictionary should be interpreted as having a meaning consistent with the meaning in the context of the related art, and unless explicitly defined in an embodiment of the present invention, an ideal or excessively formal meaning is not interpreted as

The shapes, sizes, proportions, angles, numbers, etc. disclosed in the drawings for explaining the embodiments of the present invention are illustrative and the present invention is not limited to the illustrated matters. In addition, in describing the present invention, if it is determined that a detailed description of a related known technology may unnecessarily obscure the gist of the present invention, the detailed description thereof will be omitted. When 'include', 'have', 'consist', etc. mentioned in this specification are used, other parts may be added unless 'only' is used. When a component is expressed in the singular, cases including the plural are included unless otherwise explicitly stated.

In interpreting the components, it is construed as including an error range even if there is no separate explicit description.

In the case of a description of the positional relationship, for example, when the positional relationship of two parts is described as 'on', 'on', 'on', 'beside', etc., 'right' Alternatively, one or more other parts may be positioned between two parts unless 'directly' is used.

Reference to an element or layer “on” another element or layer includes any intervening layer or other element directly on or in the middle of another element. Like reference numerals refer to like elements throughout.

The size and thickness of each component shown in the drawings are illustrated for convenience of description, and the present invention is not necessarily limited to the size and thickness of the illustrated component.

Each feature of the various embodiments of the present invention may be partially or wholly combined or combined with each other, and as those skilled in the art will fully understand, technically various interlocking and driving are possible, and each embodiment may be implemented independently of each other, It may be possible to implement together in a related relationship.

Among the accompanying drawings, FIG. 1 is a process flow diagram showing a construction method of a retaining wall installation structure according to the present invention, FIG. 2 is a construction drawing showing a retaining wall installation structure according to the present invention, and FIG. 3 is a view showing a drilling bit, FIG. 4 is a flowchart showing the process of further installing a steel structure to the retaining wall installation structure according to the present invention, Figure 5 is a flowchart showing the process of installing the deck plate assembly to the steel structure installed in the retaining wall installation structure according to the present invention, Figure 6 is a view showing the cross-sectional structure of the first insulator according to the embodiment of the present invention, Figure 7 is a view showing the cross-sectional structure of the second insulator according to the embodiment of the present invention.

1 and 2, the construction method of the retaining wall installation structure according to the present invention,

Perform excavation by excavating to a certain depth from the ground, driving a plurality of H-beams (B) close to the excavated cut surface (L), and coupling between the plurality of H-beams (B) to the cut surface (L) a first step (S1) of installing a plurality of earth plates 110 to be supported;

Step 2 (S2) of mounting a horizontal beam horizontally to connect a plurality of H-beams;

A third step (S3) of inserting an anchor (K) through the horizontal beam (120) of the second step (S2) and embedding the anchor (K) to a predetermined depth into the cut surface (L);

4 step (S4) of injecting and curing the cement paste 100 around the anchor (K) of the cut surface (L) where the anchor (K) is embedded, and curing the anchor (K) to be fixed; includes.

The first step (S1) is to dig the ground to a certain depth with an excavator to perform excavation.

The H-beam (B) is inserted at regular intervals so that it is close to the cut surface (L) excavated by excavation and is constructed so that it is vertically embedded. A plurality of H-beams B are arranged at equal intervals.

A plurality of H-beams (B) has a 'C'-shaped groove formed on the side thereof in the longitudinal direction, and both ends of the earth plate 110 are inserted into the grooves of the H-beams B on both sides. this is combined The earth plate 110 coupled in this way supports the cut surface L to withstand earth pressure.

In the second step ( S2 ), the horizontal beam 120 is mounted to connect the H-beam B and the H-beam B . The horizontal beam 120 is mounted by a connection method such as welding or bolting.

A beam having an H-shaped cross section is applied to the horizontal beam 120 , and after forming a plurality of through holes in a vertical surface, the anchors K may be coupled through each through hole.

In step 3 (S3), the anchor (K) is inserted through the horizontal beam (120), and the anchor (K) is embedded so that the anchor (K) is inserted to a predetermined depth in the cut surface (L).

Step 4 (S4) is to inject and harden the cement paste 100 around the anchor (K) of the cut surface (L) is embedded so that the anchor (K) is fixed.

Step 4 (S4) is to form a tunnel 132 by drilling to a predetermined depth using a punching bit 160 for the cut surface L, and to expand the diameter at the end of the tunnel 132, an extension part ( 134) is formed.

The anchor K is inserted up to the tunnel 132 and the extension 134 formed in this way.

Thereafter, the cement paste 100 is injected into the tunnel 132 and the expansion part 134 and hardened so as to be integrated.

The cement paste 100 is a mixture of water and cement, and after being injected into the tunnel 132 and the expansion part 134 , it is hardened and has a hard hardness after a certain period of time has elapsed.

The punching bit 160 for drilling the tunnel 132 and the extension 134 of the fourth step is, as shown in FIG. 3, a body 162 having a bit blade 164 formed on its outer surface, and the body 162 ) is formed to protrude and protrude at the end of the variable blade 166, and is formed inside the end of the body 162 and is configured to include an actuator 168 for triggering the protruding and retracting operation of the variable blade 166.

The body 162 is made of a circular rod shape, a screw thread-shaped bit blade 164 is formed on the outer peripheral surface, and a variable blade 166 is formed on the outer peripheral surface of the front end.

The variable blade 166 is inserted into the body 162 and the variable blade 166 protrudes by the operation of the actuator 168. By being rotated, the body 162 may be perforated to a larger diameter than the expanded portion 134 .

In addition, a power supply line (not shown) formed inside the body 162 and connected to the actuator 168, and a power generator provided outside the body 162 and connected to the power supply line (not shown) includes ;

The actuator 168 is driven by the hydraulic pressure generated by the power generator to rotate the body 162 at high speed.

As the body 162 rotates at high speed, the cut surface L is drilled, and preferably, the tunnel 132 is formed inclined by drilling downwardly inclined.

After the tunnel 132 is drilled to a certain depth, the extension part 134 may be formed by drilling in a state in which the variable blade 166 is drawn out.

Accordingly, the diameter of the extension 134 is larger than that of the tunnel 132 .

The diameter of the expansion part 134 is larger than the tunnel 132, and the cement paste 100 is injected and hardened in the expansion part 134 to serve as a kind of weight, and the anchor K is It is inserted therein so that it is cured integrally with the cement paste 100 so as to have a strong supporting force.

Since the bearing force for the anchor K is proportional to the length and diameter of the tunnel 132, the longer the tunnel 132 is formed or the larger the diameter is, the greater the bearing capacity for the anchor K may be.

However, depending on the characteristics of the ground, making the tunnel 132 long or forming the tunnel 132 large is more likely to be restricted, and it takes a lot of time and money to make the tunnel 132 long or large. can only be consumed.

Accordingly, in the present invention, the tunnel 132 is formed short, but time and cost can be saved by forming the enlarged part 134 at the end of the tunnel 132, but the bearing capacity for the anchor K can be strengthened.

After the fourth step (S4), a fifth step (S5) of forming the steel structure 20 in the excavated ground may be included.

Referring to FIG. 4 , in step 5 ( S5 ), the location of the terrain on which the steel structure 20 is to be installed and the height of the terrain are measured ( S101 ).

When the location of the terrain and the height of the terrain are surveyed, the ground is dug by the set depth calculated based on the survey results (S102).

When excavation is performed, rubble is laid at the excavation location (S103).

When rubble is installed, a PE film is placed on the rubble (S104).

When the PE film is placed, concrete is poured on the PE film to form a discard layer (S105).

When the discarding layer is formed, a region in which the base structure is to be formed is marked on the discarding layer (S106).

When the region is marked, the first insulating material 14 is disposed on the region (S107).

Referring to FIG. 6 , the first insulating material 14 is disposed on the upper surface of a plurality of bead method thermal insulation panels 141 and a plurality of bead method insulation panels 141 stacked in multiple layers on the upper surface of the discard layer 13, A plurality of pressure bars 142 for pressing and supporting the plurality of bead method insulation panels 141, and a rubber elastic panel 143 disposed on the upper surface of the plurality of bead method insulation panels 141, and an elastic panel ( 143) may include a first rock wool panel 144 disposed on the upper surface.

Referring back to FIG. 4 , when the first heat insulating material 14 is disposed, the first reinforcing bars and the second reinforcing bars are disposed on the first heat insulating material 14 in a grid structure ( S108 ).

When the first reinforcing bars and the second reinforcing bars are arranged in a grid structure, the formwork is arranged along the perimeter of the area so that the first insulating material, the first reinforcing bars and the second reinforcing bars are accommodated therein (S109).

When the formwork is arranged, sanitary equipment and electrical equipment are arranged (S110).

When the sanitary facilities and the electrical facilities are arranged, the anchor bolt assemblies are respectively arranged at the positions where the steel pillars are to be installed (S111).

When the anchor bolt assembly is arranged, the foundation structure 10 is formed by pouring concrete in the formwork (S112).

When the base structure is formed, the base plate is coupled to each of the anchor bolt assemblies exposed to the upper part of the base structure using a fastening member (S113).

When the base plate is coupled to each of the anchor bolt assemblies, a non-shrinkage mortar is poured between the anchor bolt assembly and the base plate to integrate the anchor bolt assembly and the base plate (S114).

When the anchor bolt assembly and the base plate are integrated, the steel columns are pre-fastened to the anchor bolt assembly exposed to the upper part of the base plate by using a fastening member while the steel columns are seated on the base plate (S115).

When the steel posts are pre-fastened to the anchor bolt assembly, the connecting beams 22 are pre-fastened to the steel posts 21 using a fastening member (S116).

When the connecting beams 22 are tentatively fastened to the steel pillars 21, it is checked whether the vertical state of the steel frame pillars 21 and the horizontal state of the connecting beams 22 with respect to the upper surface of the base structure (S117).

If there is no abnormality in the vertical state of the steel frame pillars 21 and the horizontal condition of the connecting beams 22, the anchor bolt assembly and the steel frame pillars 21 are finalized by tightening the pre-fastened fastening member, and then joined through welding. (S118).

When the anchor bolt assembly and the steel frame pillars 21 are finalized, the pre-fastened fastening members are tightened to connect the steel frame pillars 21 and the connecting beams 22 to the final assembly, followed by welding (S119).

When the steel pillars 21 and the connecting beams 22 are finalized, rust coating is performed on the steel structure using painting equipment (S120).

Meanwhile, referring to FIG. 5 , the deck plate assembly is installed on the connecting beams 22 .

Arrange the deck plates of the uneven structure on top of the connecting beams 22 (S201).

When the deck plates are seated on the upper surface of the connecting beams 22, the deck plates are connected to each other to form a deck plate assembly (S202).

When the deck plate assembly is formed, the deck plate assembly is coupled and bonded to the connecting beams 22 (S203).

When the deck plate assembly is bonded to the connecting beams 22, wiring and piping are installed between the deck plate assembly (S204).

When wiring and piping are installed between the deck plate assembly, the third reinforcing bars are reinforced in a lattice form on the upper part of the deck plate assembly (S205).

When the third reinforcing bars are reinforced on the upper part of the deck plate assembly, concrete is poured on top of the third reinforcing bars to form a support layer (S206).

When the support layer is formed on the upper surface of the deck plate assembly, a second insulating material is disposed on the lower surface of the deck plate assembly (S207).

The second heat insulating material includes a fire wood panel in contact with the lower surface of the deck plate assembly, a second rock wool panel in contact with the lower surface of the fire wood panel, and a metal corrugated panel coupled to the second rock wool panel and contacting the lower surface of the second rock wool panel. may include

In addition, the second heat insulating material includes a plurality of coupling brackets coupled to the corrugated panel and in contact with the lower surface of the corrugated panel, and a plurality of fastening bolts sequentially fastened to the second rock wool panel and the fire wood panel through the plurality of coupling brackets. and a flat panel of a metal material coupled to the plurality of coupling brackets and disposed on the lower surface of the plurality of coupling brackets.

In addition, the second heat insulating material is disposed between the corrugated panel and the flat panel, the upper surface is in contact with the lower surface of the corrugated panel, and the lower surface is in contact with the upper surface of the flat panel, the extrusion method insulation panel, the glass wool insulation panel in contact with the lower surface of the flat panel; It may include a third rock wool panel in contact with the lower surface of the glass wool insulation panel.

The corrugated panel includes a protrusion in contact with the lower surface of the second rock wool panel, a screw anchor disposed on the upper surface of the protrusion and supported by being caught in multiple stages while being press-fitted into the second rock wool panel, and spaced apart from the second rock wool panel, and a plurality of couplings It may include a depression to which the bracket is coupled.

The plurality of coupling brackets are in contact with the lower surface of the depression, a bracket body configured to receive and hang a portion of the flat panel therein, and disposed on the upper surface of the bracket body, penetrate through the depression and are supported by being caught on the upper surface of the depression. , it may include a coupling pin formed in a tubular structure through which the fastening bolt can penetrate.

The flat panel may include a panel body in contact with the lower surface of the bracket body and the lower surface of the extruded insulating panel, and a "T"-shaped hook disposed on the upper surface of the panel body, accommodated in the bracket body, and supported by the bracket body. there is.

Although the embodiments of the present invention have been described in more detail with reference to the accompanying drawings, the present invention is not necessarily limited to these embodiments, and various modifications may be made within the scope without departing from the technical spirit of the present invention. . Therefore, the embodiments disclosed in the present invention are not intended to limit the technical spirit of the present invention, but to explain, and the scope of the technical spirit of the present invention is not limited by these embodiments. Therefore, it should be understood that the embodiments described above are illustrative in all respects and not restrictive. The protection scope of the present invention should be construed by the following claims, and all technical ideas within the scope equivalent thereto should be construed as being included in the scope of the present invention.

Therefore, other implementations, other embodiments, and equivalents to the claims are also within the scope of the following claims.

B : H beam L : cut surface
100: cement paste 110: earth plate
120: horizontal beam K: anchor
132: tunnel 134: extension
160: punched bit 162: body
164: bit blade 166: variable blade
168: actuator

Claims (3)

1 step of excavating to a certain depth from the ground to perform excavation, driving a plurality of H beams to be close to the excavated cut surface, and installing a plurality of earth plates by being coupled between the plurality of H beams to be supported on the cut surface;
Step 2 of mounting a horizontal beam horizontally to connect the plurality of H-beams;
A third step of inserting an anchor through the horizontal beam of the second step and burying the anchor so that the anchor is inserted to a predetermined depth in the cut surface;
A fourth step of injecting cement paste around the cut surface where the anchors are embedded, and curing the anchors so that the anchors are fixed;
Step 4 above
A tunnel is formed by drilling the cut surface to a certain depth using a drilling bit, and an extension is formed at the end of the tunnel so that the diameter is expanded, an anchor is inserted up to the tunnel and the extension, and the tunnel and the extension Cement paste is injected into
Including; step 5 of forming a steel structure in the excavation ground after step 4
The 5th step is to measure the location of the terrain where the steel structure will be installed and the height of the terrain,
When the location of the terrain and the height of the terrain are surveyed, the ground is dug as much as the set depth calculated based on the results of the survey.
the process of laying rubble at the excavation site;
disposing a PE film on the rubble;
The process of forming a discard layer by pouring concrete on the PE film;
The process of reinforcing a plurality of steel pillars on the discard layer;
The process of installing a plurality of connecting beams in the transverse direction to connect the steel pillars;
The process of installing a deck plate assembly on the upper part of the connecting beams; including,
The process of installing the deck plate assembly,
The process of arranging the deck plates of the concave-convex structure on top of the connecting beams;
connecting the deck plates to each other to form the deck plate assembly;
The process of coupling and bonding the deck plate assembly to the connecting beams;
The process of reinforcing the third reinforcement in the form of a grid on the upper portion of the deck plate assembly;
forming a support layer by pouring concrete on top of the third reinforcing bars; including,
The process of disposing a first insulating material on the discard layer, and disposing a second insulating material on the lower surface of the deck plate assembly;
The second heat insulating material,
Firewood panel in contact with the lower surface of the deck plate assembly;
a second rock wool panel in contact with a lower surface of the fire wood panel;
a metal pleated panel coupled to the second rock wool panel and in contact with a lower surface of the second rock wool panel;
a plurality of coupling brackets coupled to the corrugated panel and in contact with the lower surface of the corrugated panel;
a plurality of fastening bolts passing through the plurality of coupling brackets and sequentially fastened to the second rock wool panel and the fire wood panel;
A flat panel made of a metal material coupled to the plurality of coupling brackets and disposed on a lower surface of the plurality of coupling brackets;
an extrusion method insulation panel disposed between the corrugated panel and the flat panel, the upper surface of which is in contact with the lower surface of the corrugated panel, and the lower surface is in contact with the upper surface of the flat panel;
a glass wool insulation panel in contact with the lower surface of the flat panel, and a third rock wool panel in contact with the lower surface of the glass wool insulation panel;
A method of constructing a retaining wall installation structure comprising a. The method of claim 1,
The drill bit for drilling the tunnel and the extension of step 4 is,
A body having a bit blade formed on its outer surface, a variable blade formed to protrude and protrude from an end of the body, and an actuator formed inside the end of the body to induce a retracting operation of the variable blade,
A method of constructing a retaining wall installation structure comprising: a power supply line formed inside the body and connected to the actuator; and a power generator provided outside the body and connected to the power supply line.

delete

Images