KR101202845B1 - Hybrid ground reinforcing method by earth anchor and soil nail - Google Patents

Abstract

The initial tension of the earth anchor tension material is applied to the ground first to initially resist some of the ground deformation loads, and in addition, the earth anchor tension material and the soil nail reinforcement material simultaneously resist the insufficient ground load. Disclosed is a ground reinforcement method by synthesizing an earth anchor and a soil nailing in one drilling hole in which the structural resistance system of the earth anchor method and the small nail method are simultaneously operated in one drilling hole.
The ground reinforcement method includes the step of introducing an initial tension force to the ground by pre-tensioning the earth anchor tension material at the ground surface in the anchorage formed in the ground inside the expected fracture surface of the ground; And a step of reinforcing the ground by the adhesive force over the entire drilling hole to allow the nail nail reinforcement installed over the entire length of the drilling hole to be fixed later in the drilling ground.

Description

HYBRID GROUND REINFORCING METHOD BY EARTH ANCHOR AND SOIL NAIL}

The present invention relates to a ground reinforcement method by synthesizing an earth anchor and a small nailing in one drilling hole. More specifically, by initially applying a load to the ground as the initial tension of the earth anchor tension member, it initially resists part of the ground deformation load, and in addition, the earth anchor tension member and the soil nail reinforcement resist resistance at the same time. The present invention relates to a ground reinforcement method by synthesizing earth anchors and soil nails in which a structural resistance system of the earth anchor method and the small nail method are simultaneously operated in one drilling hole.

In general, as a device for reinforcing and stabilizing the ground, such as the slope that is concerned about destruction, there are largely divided Soil Nail (Earth Nail) method and Earth Anchor (Earth Anchor) method.

In general, the earth anchor method is an effective method that resists the activity of the ground by incorporating a high strength steel plate (or wall) into the deep ground with high strength steel wire and introducing high tension to the steel wire. It is used.

Earth anchors, for example, drill a hole in the wall of earthenware to insert PC steel wire, then grout the mortar to fill it, and create an anchor on the back to introduce tension to bind the earthen wall and the ground together. do.

That is, through the active zone divided by the expected fracture surface (C) of the back ground of the slope structure 10 installed on the slope as shown in Figure 1a to form a perforated hole to the ground inside the expected fracture surface (C) ,

Install a tension member 20 extending over the entire length of the perforation hole and penetrating the slope structure 10;

When the injected grouting material is cured so that the grouting material 30 is injected into the drilling hole only in the ground inside the expected fracture surface,

After tensioning the tension member 20, it may be referred to a method of reinforcing the ground by fixing by wedges, etc. in the not shown pressure plate installed on the front of the slope structure (10).

Therefore, the earth anchor method, which is generally constructed of a tension material using a stranded wire and a grouting material by cement grout, may be used in various ways such as support for temporary earth wall, permanent anchor earth wall, transmission tower foundation, dam reinforcement, buoyancy anchor of underground structure, slope reinforcement, etc. Apply.

However, these earth anchor methods generally require high tension material and strong pressure plate or wall to resist them. When the tension member is relaxed at the anchorage site, tension loss occurs, and there is a problem that requires continuous management after construction.

Soil nail method, on the other hand, installs reinforcement materials such as relatively short (3 ~ 10m) steel or glass synthetic fiber on rock, and combines surface protection to protect the excavation surface with shotcrete. Stabilization of steep slopes.

That is, as shown in Figure 1b through the active zone (Active Zone) divided by the anticipated fracture surface (C) of the sloped back ground to form a drill hole to the ground inside the expected fracture surface (C), too,

Install a reinforcing material (40, rebar, etc.) extending over the entire length of the hole,

When the injected grouting material is cured by injecting the grouting material into the entire hole,

The reinforcing material 40 may be referred to as a method of reinforcing the ground by the fixing force (F2) formed between the punching hole and the grouting material by fixing the fixing nut, etc. in the pressure plate not shown in front of the slope.

Soil nail method, which is generally constructed with reinforcement using reinforcing steel and grouting with cement grout, can be applied to a wide range of tunnel reinforcement, existing structure reinforcement, slope reinforcement in addition to stabilization of cut slope or earth wall.

However, since the small nail method has a relatively weak resistance, it is difficult to apply when the deep fracture behavior of the ground and the ground where deformation is strictly limited occurs because the number of installed per unit area is large and the ground deformation is allowed to some extent.

The ground reinforcement device which combines earth anchor tension material and soil nail reinforcement is introduced.

That is, as shown in FIG. 1C, the support bar 50 extending to an arbitrary length, the front end fixing part 60 fixed to the front end of the support bar 50, and the rear end of the support bar 50 are fixed. A ground reinforcement device including a rear end fixing part 70 and a strand wire 80 connected to the front end fixing part 60 and the rear end fixing part 70 is introduced.

Accordingly, the tensile reinforcement device is settled by filling the cement paste into the boring hole in the state in which the tensile wire 80 is provided with a tensile force and the support bar 50 is provided with a compressive force by tensioning the strand wire 80 of the device.

After curing the cement paste, the ground can be stabilized by fixing the support bar 50 and the strand 80 with a pressure plate.

However, according to this method, using the reinforcement that introduced the compressive force to the support bar 50 by the strand (80), the same method as the small nail simply improved the reinforcement does not contribute significantly to the stability of the ground, so the general small nail method and In comparison, it is not an economically improved method.

Therefore, the present invention uses the ground reinforcement device that combines the advantages of the earth anchor method and the Soil Nail method, by the ground anchor method performs some ground reinforcement role as the initial tension, and the lack of ground reinforcement tension material and end for To solve the ground reinforcement method by combining earth anchor and soil nailing in one drilled hole that can have more effective and economical ground reinforcement effect by enabling the fixed soil nail reinforcement to act as additional ground reinforcement. It is assumed that the technical problem.

Therefore, the present invention is the construction method and structure shape to apply the small nails in the same way in order to make the construction by the small equipment that is the advantage of the small nail and the low cost of construction as it is,

In order to prevent displacement by surface tension and collapse of surface sediment, which is an advantage of earth anchor method, tension material is settled by grouting on stable ground inside anticipated fracture surface, and then tension is applied to earth nail method. The initial tension was to be introduced. The present invention

Ground reinforcement method for reinforcing the ground by inserting the composite ground reinforcement device equipped with earth anchor tension material, soil nail reinforcement material and grouting material injection hose together into the perforated hole formed on the inner and outer ground of the expected fracture surface of the ground. To

Fixing the earth anchor tension material in the anchorage formed by grouting on the inner ground of the expected fracture surface of the ground and introducing the initial tension to the ground by tensioning at the ground surface; And

Soil nail reinforcement installed over the entire length of the drilled hole is to be settled later in the perforated ground outside the expected fracture surface and to reinforce the ground by the adhesive force over the entire drilled hole in the synthesis of earth anchor and soil nailing The ground reinforcement method is provided.

Also preferably in the case of the initial tension is introduced into the ground first insert the synthetic ground reinforcement device into the drill hole and then the primary grouting material is injected only to the ground inside the expected fracture surface of the ground by the packer, the injected 1 After the secondary grouting material is cured, the secondary grouting material is additionally injected into the boring hole so as to be made by tensioning and fixing only the earth anchor tension material on the ground surface before the secondary grouting material is cured.

Also preferably, the ground reinforcement by the reinforcing material for the soil nail is made by the step of allowing the reinforcing material for the soil nail to be fixed in the perforated ground after curing the secondary grouting material injected into the perforation hole.

Also preferably, the non-tensioning tension material for the earth anchor is used so that the earth anchor tension material does not directly contact the secondary grouting material injected into the drilling hole.

In addition, the anchor anchor tension material and the soil nail reinforcement is preferably fixed in the perforated ground is to be fixed by the fixing member and the fixing nut for the tension member including a wedge on the pressure plate installed to contact the surface of the perforated ground.

The composite ground reinforcement device of the present invention allows the construction of small equipment by introducing a small initial tension on the slope and the application of a small pressure plate, so that in addition to the initial tension, the small nail reinforcement and the earth anchor strand are jointly resistant to the ground behavior. So

Like the small nail method, it is possible to use small equipment and apply small pressure plate.

As the initial tension of the earth anchor method, the ground reinforcement installation interval by the small nail method can be extended and economic ground reinforcement is possible.

It is possible to prevent the surface sedimentation by the introduction of the initial tension force, and to check the adhesion of the grouting material to prevent the secondary work.

The introduction of the initial tension force by the earth anchor method strengthens the displacement suppression force than the small nail method, so that two structural effects by the small nail method and the earth anchor method can be obtained.

The scope of the present invention is shown by the following claims rather than the above description, and all changes or modifications derived from the meaning and scope of the claims and their equivalents should be construed as being included in the scope of the present invention. do.

Figure 1a is a ground reinforced cross-sectional view by the conventional earth anchor method,
Figure 1b is a ground reinforced cross-sectional view by the conventional small nail method,
Figure 1c is a nail nail reinforcement combines the tension member and the reinforcement previously introduced,
Figure 2 is a cross-sectional view of the installation of the composite ground reinforcement device according to the present invention,
3 is a loading action diagram of the composite ground reinforcement device according to the present invention,
4A, 4B and 4C are flowcharts of the ground reinforcement method using the composite ground reinforcement device according to the present invention.

DETAILED DESCRIPTION Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art may easily implement the present invention. The present invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. In the drawings, parts irrelevant to the description are omitted in order to clearly describe the present invention, and like reference numerals designate like parts throughout the specification.

<Synthetic ground reinforcing device 100 according to the present invention>

2 illustrates a reinforcement device 100 in which the earth anchor and the soil nail are synthesized according to the present invention.

First, the tip fixing head 110 is formed at the tip of the reinforcing device 100, and the tip fixing head is a bulbous role and grouting injection of the earth anchor tension member 120 by primary grouting material injection and curing. It is formed of a cylindrical sphere that serves as a guide member for setting the installation position of the hose 140.

The end fixing head 110 is fixed to the end of the anchor anchor material 120 of the present invention, the soil nail reinforcement 130 and the grouting injection hose 140 is extended to the inner end of the hole drilling hole Will be

Accordingly, the tip fixing head 110 is tightened by an insertion hole 111 into which a reinforcement member for a soy nail, such as a reinforcing bar formed with a thread, is inserted into the outer peripheral surface, and an earth anchor tension member 120 such as an unattached strand. A plurality of hose insertion holes 113 into which the fixing holes 112 and the primary grouting injection hose 140 are inserted are formed,

The insertion hole 111 is formed so as to penetrate through the tip fixing head 110 by the number of reinforcing material for the nail nail (130),

The fixing hole 112 is formed to penetrate the front fixing head 110 by the number of the tension member 120 for earth anchors,

The hose insertion hole 113 is also formed to penetrate the front fixing head 110 by the number of grouting injection hose 140.

The reinforcement device 100 of the present invention can be seen that the earth anchor tension member 120, the soil nail reinforcement 130 and the primary grout injection hose 140 to be installed together.

The earth anchor tension member 120, the soy nail reinforcement member 130 and the grouting injection hose 140 to maintain the spaced apart from each other in the drill hole and the anchor anchor tension member 120 is tightened by tightening, etc. If possible, the intermediate fixing head 110a may be additionally installed in accordance with the fixing length of the at least one synthetic ground reinforcement device 100.

This intermediate fixing head (110a) is to be installed only in the fixing site to be described later to ensure a sufficient bulbous role.

In addition, if necessary, a spacer 150 serving as a kind of spacer is installed between the tip and the intermediate fixing heads 110 and 110a so that the earth anchor tension member 120, the soil nail reinforcement 130, and the grouting injection hose ( 140) do not leave the position during construction.

The spacer 150 has a disc shape, and a semi-circular groove is formed in the central through hole and the outer circumferential surface thereof, so that the reinforcement member for the small nail 130, the tension member 120 for the earth anchor and the hose 140 for grouting injection are structurally required. Considering the required number of will be properly arranged and supported.

In addition, since there is no reason for the fixing head to serve as a bulb of the earth anchor tension member 120 in the activity site to be described later, only the spacer 150a is installed in the activity field.

Furthermore, the packer 170 is installed inside the drilling hole H located in the inner ground G1 of the anticipated fracture surface C. For this purpose, the packer 170 is also provided with an earth anchor tension member 120 and a soil nail reinforcement material. 130 and grouting injection hose 140 will form a number of holes through which they can pass.

The packer 170 is the primary grouting when the primary grouting material 160 is injected through the hose 140 for grouting injection into the drilling hole H of the inner ground G1 of the expected fracture surface C. The ash 160 has the inherent function of the packer which is injected into only the inner ground G1 of the expected fracture surface C so as to be cured, and the punching hole H is fixed by the packer 170. And the activity will be divided into the drill hole (H2).

At this time, the anchoring hole (H1) is a section in which the tension material for earth anchors is fixed after the curing of the primary grouting material 160,

The activity drilling hole (H2) may be referred to as a section in which the reinforcing material for the soy nail 130 is fixed at the same time as the primary grouting material of the fixing hole (H2) after curing the second grouting material.

Thus, in the anchoring punching hole H1, as shown in FIG. 3, the initial resistance to the ground deformation load is due to the resistance of the adhesive force at the contact portion between the primary grouting material 160 and the punching hole, which is fixed and cured by the earth anchor tension member 120. The tension force (F) can be introduced to suppress the initial displacement of the ground and effectively resist the collapse of the surface soil.

That is, the tension force of the earth anchor tension member 120 in the present invention because the small nail reinforcement member 130 further resists the ground deformation load, so that the tension force is introduced to significantly reduce the size than when using the conventional earth anchor method alone. It will be possible to miniaturize the equipment and enable the small size of the pressure plate.

Next, as shown in FIG. 3, the nail nail reinforcement 130 is fixed to the secondary grouting material 180 cured in the active drilling hole H2 by the reinforcing material for the nail nail 130 extending from the fixing hole H1. It can be seen that it is possible to effectively secure the main ground reinforcing effect in addition to the earth anchor tension member 120 by the attachment force (F1, F2) in the contact with the drilling hole.

Thus, the synthetic ground reinforcement device 100 according to the present invention is to make full use of the most economical nail reinforcement material 130, but the earth to be able to effectively suppress the displacement of the ground with the initial tension and effectively resist the collapse of the surface soil It can be said that the method using the anchor tension material 120 at the same time.

Therefore, it can be seen that the process of determining the installation position of the packer 170 by determining the length of the anchoring hole H1 is very important. The length of the anchoring hole H1, that is, the length of the anchorage is an anchor anchor for earth anchors. Initial tension by (120) and later enough to be able to resist the tensile force transmitted by the installation of the reinforcement material for the soil nail 130, but should be positioned to extend to the inner ground of the expected fracture surface (C).

In addition, the soil nail reinforcement 130 is extended from the inner ground of the expected fracture surface (C) to the ground surface (G3) through which the final boring hole is formed via the outer ground to determine the active drilling hole (H2) ,

The extension length of the entire drilling hole H is determined by the final fixing hole H1 and the active hole H2.

In addition, the present invention according to the conventional ground anchoring method on the ground (G1) of the expected fracture surface (C) on the basis of the position where the packer 170 is installed (which is determined by calculating the required length of the actual anchorage). So that the ground reinforcement mechanism is applied as it is,

Ground reinforcement by the above method is applied by applying the soil reinforcement mechanism by the Soil Nail method to all the drilled holes covering the projected fracture surface (C) inner ground (G1) and the projected fracture surface (C) outer ground (G2). It can also be seen that the design can be applied as it is.

Ground Reinforcement Method by Combining Earth Anchors and Soil Nails

The ground reinforcement method by synthesizing the earth anchor and the soil nail may be referred to as a method of reinforcing a slope using the synthetic ground reinforcement device 100 according to the present invention.

Looking at these methods in the order of construction as follows.

First, as shown in FIG. 4A, it can be seen that the slope due to sectioning and filling is formed into a slope, and the expected fracture surface (C) outside the ground (G2) is predicted failure unless otherwise reinforced by the expected fracture surface (C). There is a fear of collapse while sliding along the surface (G) inner ground (G1).

In the prior art, by forming an aperture hole to penetrate the outer surface G2 and the inner ground G1 of the expected fracture surface C by an economical soil nail method, and inserting a reinforcement material for the soil nail in the hole, grouting Soil reinforcement was carried out by injecting ash and curing. In most cases, the most economical method among the current ground reinforcement methods is used, but the number of drill holes is the most.

Of course, earth anchors can be used to reinforce the ground by forming anchorages in the inner ground of the expected fracture surface (C). The construction is complicated and economically disadvantageous because a rigid structure that can withstand it must be formed.

In addition, in the case of using a ground reinforcement device that combines the conventional tension member and the support bar (Fig. 1c) when the grouting (cement injection material) in the state that the compression force is introduced to the support bar by the tension member

This simply shows the effect of improving the reinforcement of the small nail and there is a problem that it may be difficult to expect a sufficient ground reinforcement effect because it does not directly introduce tension to the ground.

In other words, it is a problem that the earth anchor tension material to be used only for the purpose of introducing prestress to the reinforcement for soil nails can not be an effective ground reinforcement method.

Thus, the present invention first, as shown in FIG. C) It is formed to extend to the inner ground G1 of the expected fracture surface C via the outer ground G2.

At this time, it can be seen that the total extension length of the drilling hole (H) is determined by the final anchoring hole (H1) and the active hole (H2).

Next, as described above, the tip fixing head 110, the intermediate fixing head 110a, the spacer 150 is the earth anchor tension member 120, the soil nail reinforcement 130 and the grouting injection hose 140 Installed with

The composite ground reinforcement device 100 of the present invention, in which the packers 170 and 170a are set to have a fixed hole H1 formed therein, is inserted and installed in the hole H.

Next, using the compressor for grouting injection not shown as shown in Figure 4b to the packer 170 through the grouting injection hose 140 installed in the synthetic ground reinforcement device 100 It is injected into the fixing puncture hole (H1) is separated by the curing.

At this time, it is important to first cure the first grouting material 160, and then to anchor the tension anchor 120 for earth anchor on the ground surface (G3).

This is because the tension force introduced to the earth anchor tension member 120 can sufficiently resist the anchoring hole H1 by the attachment force so as to partially suppress the displacement of the ground and effectively resist the collapse of the surface soil. can do.

To this end, the present invention injects and cures the primary grouting material 160 only in the anchoring hole H1 by the packer 170, and then passes through the active boundary surface C from the packer 170 to the ground surface G3. The secondary grouting material 180 is injected into the activity drilling hole H2.

The secondary grouting material 180 is additionally injected into the activity drilling hole (H2) by using a separate injection tube not shown, and the secondary grouting material 180 by using the packer 170a additionally installed in the drilling hole if necessary. ) Can be injected into the activity drilling hole (H2).

At this time, upon installation of the composite ground reinforcement device 100 according to the present invention, the earth anchor plate tension member 120 and the soil nail reinforcement member 130 penetrates the packer 170a and is installed on the ground surface G3. ) To extend slightly.

The acupressure plate 200 is fixed to the fixing hole 210 and the fixing nut 240 to allow the earth anchor tension member 120 to be fixed by the anchor anchor tension member including wedges as shown in FIGS. 2 and 4b. It can be seen that the through-hole 220 and the injection hole 230 into which the grouting injection hose 140 is inserted are formed so that the reinforcement material 130 for the nail is fixed.

Next, before the secondary grouting material 180 is cured, the earth anchor tension member 120 is fixed after being tensioned by the fixing unit 250 in the pressure plate. This is to prevent this because when the secondary grouting material 180 is cured, the initial tension force is not sufficiently transferred into the ground, but is offset from the ground surface and the effect of the tension force is lost.

Thus, the required tension is introduced first into the final anchoring hole H1 so that the displacement of the ground can be partially suppressed and the surface soil can be effectively resisted.

Next, as shown in FIG. 4c, the soy nail reinforcement member 130 is fixed to have the reinforcement effect of the soy nail reinforcement member 130 according to the present invention, which is after the secondary grouting material 180 is cured. On the pressure plate 200, the protruding end of the reinforcing material for the nails extending to the through hole 220 formed in the pressure plate 200 is to be finally fixed by the fixing nut in the pressure plate.

Thus, through the hole 220 of the nail plate 200 through the reinforcing material 130 for the nail nail extending from the tip of the anchoring hole (H1) to the pressure plate 200 installed on the drilling ground via the outer ground of the expected fracture surface. Final fixation using the fixing nut 250 to secure the adhesive force between the secondary grouting material 180 and the activity drilling hole H, so as to have a more economic ground reinforcement effect together with the earth anchor tension material. It can be seen.

100: composite ground reinforcement
110: tip settling head
110a: middle fixing head
120: tension member for earth anchor
130: Soil Nail Reinforcement
140: grout injection hose
150,150a: spacer
160: primary grouting material
170.170a: Packer
180: secondary grouting material
200: pressure plate

Claims (5)

Ground to reinforce the ground by inserting a composite ground reinforcement device equipped with earth anchor tension material, soil nail reinforcement material and grouting material injection hose together into one drilling hole formed over the inner and outer grounds of the expected fracture surface of the ground. In the reinforcement method,
Introducing an initial tension force into the ground by pre-tensioning the anchor anchor tension material on the ground surface in the anchorage formed on the inner ground of the expected fracture surface of the ground; And reinforcing the ground by the adhesive force over the entire drilling hole by allowing the nail nail reinforcement installed over the entire length of the drilling hole to be settled later in the drilling ground outside the expected fracture surface.
The step of introducing the initial tension force into the ground first, after inserting the synthetic ground reinforcement device into the drill hole, the primary grouting material is injected into only the ground inside the expected fracture surface of the ground by the packer, so that the primary grout material is cured. After the tension material for the earth anchor in the ground surface (G3) to tension the line,
The secondary grouting material is additionally injected into the drilled hole after curing the injected primary grouting material so as to be made by tensioning and fixing only the earth anchor tension material on the ground surface before the secondary grouting material is cured. Ground reinforcement method by combining earth anchor and small nailing in one drilling hole. delete According to claim 1, Ground reinforcement by the reinforcing material for the soil nail
After the second grouting material is injected into the perforated hole outside the expected fracture surface, the earth anchor and the soil nailing are synthesized in a single hole, characterized in that the reinforcing material for the nail is fixed by the ground surface. Ground reinforcement method by According to claim 3, wherein the earth anchor tension material is a non-perforated tension material is used so that the earth anchor tension material is not directly in contact with the secondary grouting material injected into the drilling hole outside the expected fracture surface. Ground reinforcement method by combining earth anchor and small nailing in hole. 4. The anchor anchor tension member and the nail nail reinforcement member of claim 3, wherein the earth anchor tension member and the soil nail reinforcement member are fixed to the ground surface by anchoring anchor anchors including wedges and a fixing nut for reinforcing nail nails. Ground reinforcement method by synthesizing earth anchor and soil nailing in one drilling hole, characterized in that.

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