KR100763033B1 - A prestressing soil nailing structure - Google Patents

Abstract

The present invention relates to a reinforcing material used to compensate for the lack of stability due to sedimentation of soil or loss of soil. In particular, a rebar or steel bar is provided at the inner circumference of a pipe reinforcing material to prevent soil collapse and rockfall. And a nail nailing structure for improving the tensile strength of the pipe reinforcement by tightening with a tightening cap, and installing a PC strand in the center of the inner circumference of the pipe reinforcement, and a saw nailing structure for improving the tensile strength of the pipe reinforcement by tensioning the PC strand. will be.

In the reinforcement of the present invention, a pipe reinforcement is inserted into a hole drilled in the ground to withstand the back pressure of the ground, and the compression or tensile prestressing is applied to the outer circumferential surface of the inserted pipe reinforcement to offset the tensile stress generated in the pipe reinforcement The displacement of the excavation surface is suppressed. As a result, a more stable reinforcing structure capable of preventing the soil from falling down and falling rocks from the rock walls can be provided on the ground.

Description

A prestressing soil nailing structure

Figure 1a is a detailed view of the reinforcing material used in conventional saw nailing, Figure 1b is a side view of a conventional reinforcement installed on the rock wall by the saw nailing.

2 is a detailed view of a pipe reinforcement used in the prestressing saw nailing structure described in the first embodiment of the present invention.

3 is a side view of a pipe reinforcement used in the prestressing saw nailing structure described in the first embodiment of the present invention.

4 is a view showing a saw nailing structure when the pipe reinforcement of the first embodiment of the present invention is inserted into the ground.

5 is a view showing a prestressing saw nailing structure using the pipe reinforcement of the first embodiment of the present invention.

FIG. 6A is a detailed view of a pipe reinforcement used in the prestressing saw nailing structure described in the second embodiment of the present invention, and FIG. 6B is a side view of the pipe reinforcement.

7 is a side view of a pipe reinforcement used in the prestressing saw nailing structure described in the second embodiment of the present invention.

8 is a view showing a prestressing saw nailing structure when the pipe reinforcement described in the second embodiment of the present invention is inserted into the ground.

9 is a view showing a prestressing saw nailing structure when the pipe reinforcement of the second embodiment of the present invention is inserted into the ground.

* Description of the sign

1, 11. pipe reinforcement 2. steel rod

3. Tightening cap 4. Fixing protrusion

5. Spacer 12. Strand

8, 13. Plate 14. Fixture

The present invention relates to a reinforcing material used to compensate for the lack of stability due to sedimentation of soil or loss of soil. In particular, a rebar or steel bar is provided at the inner circumference of a pipe reinforcing material to prevent soil collapse and rockfall. Soil nailing structure that introduces tensile force to pipe reinforcement to improve tensile resistance by tightening with tightening cap and PC strand is installed in the center of inner circumference of pipe reinforcement, and this PC strand is stretched after grouting curing and tensioned to pipe reinforcement It relates to a saw nailing structure that improves the resistance.

Soil nailing is generally recognized as an advantageous method in terms of air shortening and cost reduction, and is being applied to the stability of slopes and flexible support for excavated surfaces, and its application is widely spreading.

Currently, the used nail nailing is described as follows.

1A is a detail view of a reinforcement used in conventional saw nailing. As shown in FIG. 1A, the saw nailing may be constructed with the reinforcement 100, the spacer 101, and the grouting 102.

Here, the description of the saw nailing briefly, perforated in the soil, put the reinforcing material 100 (reinforcing bar, steel bar, etc.) and filling the interior of the space with cement milk, the front surface is treated with shockcrete to integrate the reinforced soil body It distinguishes from the back ground that is not reinforced and resists earth pressure on the back, so it is externally shaped like a conventional gravity retaining wall.

As such, the saw nailing is a filling material (eg, cement milk) that is firmly filled in the reinforcement 100 tightly inserted in the perforated hole and the void space around the perforated hole, as shown in FIG. 1B. ) Is faithfully positioned with the spacer 101 so that the deformation-inducing force of the surrounding ground is resisted by the reinforcement 100.

That is, the saw nailing basically inserts reinforcement materials that can resist tensile force, shear stress and bending moment at relatively tight intervals to suppress the increase of the overall shear strength and the displacement caused by the ground, and also to be expected during or after excavation work. It is to limit relaxation.

However, the conventional reinforcement described in FIG. 1 has a limitation in tensile stress to withstand the load of the ground for such a nail nailing, and when the reinforcement is embedded in the ground, the displacement of the force is external to the excavation surface. Since present in, there was a problem difficult to form a stable reinforcing structure.

For this reason, the conventional nail nailing has a limitation that can not form a more stable structure to withstand the load of earth pressure generated in the ground.

An object of the present invention for solving the above problems is to insert a steel bar with a spacer in the center of the pipe reinforcement, to tighten the steel bar using a tightening cap to tension the outer circumferential surface of the pipe reinforcement, the tensioned pipe reinforcement to the ground After inserting, after the grout curing is completed, the tightening cap connected to the pipe reinforcement and the steel bar inside the pipe reinforcement are removed, thereby compressing the outer circumferential surface of the pipe reinforcement to offset the tensile stress generated in the pipe reinforcement and suppressing displacement movement of the excavation surface. Provides prestressing saw nailing structure.

In addition, another object of the present invention is that the PC strand is inserted into the inner center of the pipe reinforcement, the PC strand is extended to the outside through the inclined insertion hole of the plate for fixing the pipe reinforcement and the PC strand together, this extended By tensioning the PC strands after grouting curing, the outer circumferential surface of the pipe reinforcement is compressed to offset the tensile stress of the pipe reinforcement and provide a prestressed saw nailing structure that suppresses displacement movement of the excavation surface.

In order to achieve the above object, the ground to form a hole of a predetermined diameter through the drilling means at a suitable position, insert a reinforcement on the hole, and fill the interior of the hole and the space in the reinforcement with cement milk In the nail nailing structure for grouting, and after the grouting to cast the excavation surface of the ground with shockcrete,

A female reinforcement formed at both ends and a pipe reinforcement inserted into the drilling hole to withstand the upper pressure of the ground;

A steel bar positioned at an inner circumference center of the pipe reinforcement and fixed with a spacer formed at an outer circumference;

Covering the outer circumference of the both ends of the pipe reinforcement, the inner thread is formed in the inner circumference to press the steel bar in combination with the female screw of the pipe reinforcement, and constitutes a tightening portion having a fixing projection for fixing the steel bar once inside do.

Preferably, before inserting the pipe reinforcement into the drill hole, tighten the tightening portion connected to the pipe reinforcement to pressurize the steel rod, loosen the tightening portion after the grouting, and remove the steel rod inside the pipe reinforcement. Configured to compress the reinforcement.

In addition, the ground is formed through the drilling means at a suitable position, the drill hole of a predetermined diameter, the reinforcing material is inserted into the drilling hole, the inside of the hole and the inner space of the reinforcing material with grout to grout, and after the grouting In the nail nailing structure for pouring the excavated surface of the ground with shockcrete,

A pipe reinforcement inserted into a hole drilled to withstand the upper pressure of the ground;

A stranded wire located in the center of the inner circumference of the pipe reinforcement,

Plates on both sides having an inclined insertion hole so that the strand can extend to the outside, and fixing the pipe reinforcement to the ground;

It comprises a fixture for fixing the strand extending outwards through the inclined insertion port of the support member.

Preferably, after the grouting, the pipe reinforcement is compressed by pressurization of the plate by tensioning the strand located in the inner circumference of the pipe reinforcement.

Preferably the pipe reinforcement consists of steel pipes or bamboo.

Hereinafter, with reference to the accompanying drawings, the configuration and operation effects according to the present invention will be described in detail as follows.

Example  One

2 is a detailed view of the pipe reinforcement 1 used in the prestressing saw nailing structure described in the first embodiment of the present invention.

3 is a side view of a pipe reinforcement 1 used in the prestressing saw nailing structure described in the first embodiment of the present invention.

As shown in Figures 2 and 3, the configuration used in the prestressing saw nailing structure of the present invention is composed of a pipe reinforcement (1), a steel bar (2), a tightening cap (3), a spacer (5). Here, the pipe reinforcement (1) is made of a steel pipe, the outer periphery of both ends of the pipe reinforcement (1) is formed with a female screw to be coupled to the tightening cap (3). In addition, the steel bar 2 located in the inner circumferential center of the pipe reinforcement 1 is inserted into the pipe reinforcement 1 after being mounted in the center of the pipe reinforcement 1 after mounting the spacer 5 at regular intervals. Here, the steel bar 2 may be used in place of a re-bar. In addition, the tightening cap 3 forms a male screw on the inner circumference thereof so as to be coupled to the female screw of the pipe reinforcement 1, and forms a fixing protrusion 4 capable of tightly fixing the steel bar 2 to the inner end thereof.

The steel bar 2 can be tightly fixed by turning the capping caps 3 mounted at both ends so as to cover the outer periphery of both ends of the pipe reinforcement 1 having such a configuration. Here, the end of the steel bar (2) is precisely located in the center of the pipe reinforcement (1) by a fixing projection (4) protruding inside the tightening gap (3).

Once the steel rods 2 are tightly fixed to the tightening caps 3, the two tightening caps are rotated to tighten the steel rods 2, and thus the steel bars 2 are tightened on both sides with a strong force (not shown). Since the steel bar 2 is compressed to the center like the arrow of 4, the outer circumferential surface of the pipe reinforcement 1 is tensioned in the central direction opposite to the steel bar.

4 is a view showing a saw nailing structure when the pipe reinforcement of the first embodiment of the present invention is inserted into the ground.

As shown in FIG. 4, the drilling holes 6 are formed in accordance with a nailing structure in which the pipe reinforcement 1 with its outer peripheral surface tensioned in a direction opposite to the compression direction by tightening the tightening cap 3 connected to the pipe reinforcement 1. To the inside of the hole (6) and the space in the pipe reinforcement (1) filled with cement milk and grouted, the plate 8 so that the inserted pipe reinforcement (1) is in close contact with the ground (7) ) And prevent the pipe reinforcement (1) from moving using bolts and nuts (9). 4B is an enlarged view showing the structure in which the tightening cap 3 is connected to the pipe reinforcement 1.

5 is a view showing a prestressing saw nailing structure using the pipe reinforcement of the first embodiment of the present invention.

As shown in FIG. 5, after grouting and curing, loosen the cap 3 connected to one end of the installed pipe reinforcement 1 to reinforce the tensile force of the pipe reinforcement 1, and By removing the steel bar 2 located in the inner center, the outer circumferential surface of the pipe reinforcement 1 is compressed to the center, so that the displacement of the force of the compressed pipe reinforcement 1 acts into the ground and thus the pipe reinforcement 1 It is possible to offset the tensile stress from the ground 7 generated in the ground, and the portion indicated by the dotted line causes the displacement inward as in the direction of the arrow, so that the displacement near the excavation surface can be suppressed from moving to the outside. have.

In addition, although not shown, when such a pipe reinforcement is inserted into a plurality of grounds to remove one of the tightening caps connected to the ends of the pipe reinforcement, since the outer peripheral surface of the pipe reinforcement as described above is compressed to the center, the ground 7 In addition to canceling the tensile stress of the pipe reinforcing material (1) generated from the above, displacement movement in the vicinity of the excavation surface can be suppressed.

As the pipe reinforcement 1 is thus reduced, the soil inside the ground 7 is pulled together, so that the prestressing saw nailing structure can be used to prevent the ground 7 from falling down or falling rocks from the rock wall. It can form a stable reinforcement structure.

Example  2

Embodiment 2 having the same principle as Embodiment 1 above will be described below.

6 is a detailed view of the pipe reinforcement 11 used in the prestressing saw nailing structure described in the second embodiment of the present invention, and FIG. 6B is a side view of the pipe reinforcement. As shown in FIGS. 6A and 6B, the configuration used for the prestressing of the present invention is composed of a pipe reinforcement 11, a PC strand 12, a plate 13, a fixture 14, and an insertion hole 15. Here, the reinforcing material 11 is made of a steel pipe, the fastener 14 has a toothed tooth so that the center of the PC strand 12 can be located, the insertion hole 15 of the plate 13 forms an oblique inclination have.

7 is described in detail through a side view of the pipe reinforcement 11 used in the prestressing saw nailing structure described in the second embodiment of the present invention, as shown in FIG. 7, outward of the PC strand 12. The reinforcing material 11 is hermetically adhered to the plate 13, and the PC strand wire 12, which is provided in the center of the inner side of the reinforcing material 11, extends through the inclined insertion hole 15 formed in the plate 13 to the outside. It is. A toothed fixture 14 is inserted to secure this extended PC strand 12 to the plate 13.

8 is a view showing a prestressing saw nailing structure in which the pipe reinforcement 11 having the above-described configuration is inserted into the ground 18.

First, the pipe reinforcement 11 is inserted into a hole 17 drilled in the ground 18 so as to withstand the back pressure of the ground 18, and in the inner center of the pipe reinforcement 11 of the pipe reinforcement 11 The PC stranded wire 12 longer than the length is provided. In addition, the PC strands 12 and the reinforcement 11 is installed so that the plate 13 on both sides facing in different directions so as to be assembled, the plate 13 is in close contact with the ground 18, The PC strand 12 extends to the outside via the insertion hole 15 drilled into the plates 13 on both sides. Here, the plate 13 is sized to cover the pipe reinforcement 11 as well as the entire perforated hole 17 in close contact. In addition, the PC stranded wire 12 extending through the insertion opening 15 has a fixing tool 14 for fixing to the plate 13.

In this way, a tensioner such as a sole cone is fixed after fixing one side of the PC strand, and grouting the extended portion of the PC strand 12 located in the inner center of the pipe reinforcement 11 installed according to the prestressing saw nailing structure. Tension of the pipe reinforcement 11, the pipe reinforcement 11 receives a compressive force by pressurization of the plate, so that the outer circumferential surface of the pipe reinforcement 11 is compressed so that the displacement of the force of the compressed pipe reinforcement 11 is grounded. Since it acts internally, the tensile stress from the ground 18 generated in the pipe reinforcement 11 can be canceled, and the portion indicated by the dotted line is displaced inward, as shown by the arrow direction, so that the displacement of the excavation surface is moved to the outside. The movement can be suppressed.

In addition, although not shown, such a pipe reinforcement is inserted into a plurality of ground, the outer peripheral surface of the pipe reinforcement 11 inserted into the ground 18 by tensioning the PC strand 12 by a tensioner (not shown) is plate In the case of compression by pressing, the outer circumferential surface of the pipe reinforcement as described above is compressed to the center, thereby not only canceling the tensile stress of the pipe reinforcement 1 generated from the ground 7, but also displacing the displacement movement near the excavation surface. It can be suppressed.

As the pipe reinforcement 1 is thus reduced, the soil inside the ground 7 is pulled together, so that the prestressing saw nailing structure can be used to prevent the ground 7 from falling down or falling rocks from the rock wall. It can form a stable reinforcement structure.

FIG. 9 is a view showing a prestressing saw nailing structure when the pipe reinforcement 11 of the second embodiment of the present invention is inserted into the ground 18. As shown in FIG. The bar shown in FIG. 9 has the same structure as that of FIG. 8, and thus description thereof is omitted. However, the pipe reinforcement 11 is made of bamboo. By using such bamboo, it can perform the same function as the steel pipe used for the saw nailing, and can be environmentally friendly and cost-saving.

Moreover, also in Example 1, it is not only limited to a steel pipe but can also use it as bamboo as a pipe reinforcing material 11.

Therefore, by using the action of compressing the outer circumferential surface of the pipe reinforcement inserted into the drilling hole in the ground by the pre-stressing saw nailing structure having the same principle as in Example 1 and 2, the tensile stress generated in the pipe reinforcement to cancel It is possible to reduce the displacement movement of the excavation surface to prevent the earth and sand collapse.

It is described here in the table compared below that even if bamboo is used as the pipe reinforcement 11 instead of the steel pipe described in Example 2, it can have the same tensile force as the steel pipe.

Table 1 below shows the tensile strength of various metal materials.

Table 1 below shows the tensile strengths of various nonmetallic materials.

As a result, even when bamboo is used, a stable reinforcing structure such as a steel pipe can be formed as compared in the table.

The pipe reinforcing material 11 used in the saw nailing structure of the present invention may be used as long as it is not limited to steel pipes or bamboo, and can use various materials as long as it can perform the same function without departing from the scope of the invention.

As described in the present invention, by removing the steel bar by loosening the capping cap tightened on the outer periphery of the pipe reinforcement both ends according to the present invention, it is possible to offset the tensile stress generated in the pipe reinforcement inserted into the ground by soaking the outer peripheral surface of the pipe reinforcement By making the displacement of the excavation surface acting on the ground act inside, it is possible to suppress or reduce the displacement of the excavation surface.

In addition, by compressing the pipe reinforcement by tensioning the PC strands installed in the center of the pipe reinforcement after grouting by the saw nailing structure of the present invention, it is possible to offset the tensile stress generated in the pipe reinforcement, the excavation surface acting on the ground By causing the displacement to act internally, it is possible to suppress or reduce the displacement of the excavation surface.

As such, a more stable reinforcement structure can be formed by using a prestressing saw nailing structure capable of preventing the soil from falling down or falling rocks from the rock wall.

Claims (2)

In the saw nailing structure for forming a hole having a predetermined diameter through a drilling means at a suitable position of the ground, and filling and grouting the inner space of the drilling hole with cement milk, A female reinforcement formed at both ends and a pipe reinforcement inserted into the drilling hole to withstand the upper pressure of the ground; A steel bar positioned at an inner circumference center of the pipe reinforcement and fixed with a spacer formed at an outer circumference; Covering the outer circumference of the both ends of the pipe reinforcement, the inner thread is formed in the inner circumference to press the steel bar in combination with the female screw of the pipe reinforcement, and includes a fastening portion having a fixing projection for fixing the steel bar once inside Prestressing saw nailing structure, characterized in that configured. The method of claim 1, Compress the pipe reinforcement by tightening the tightening part connected to the pipe reinforcement to press the steel bar before inserting the pipe reinforcement into the drilling hole, loosening the tightening part after the grouting, and removing the steel bar inside the pipe reinforcement. A prestressing saw nailing structure, characterized in that it is configured to.

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