KR20090030424A - Soil-nail for reinforcing a slope - Google Patents

Abstract

A soil nail for the slope reinforcement is provided that the management to the shear stress generated in the forecast activity surface of four sides is possible since the shear resistance of nail, and the bend resistance power and drawing resistance are strengthened. A soil nail for the slope reinforcement comprises a rod-shaped nail(110) which is inserted so that the head be exposed to the perforation hole(103) punched in four sides(101), a sheath pipe(120) covering the outer circumference of nail from the head of nail with the regular length, a hook-shaped packer(130) which is installed at the nail, and which expands and adheres closely with the perforation hole if the urethane drug solution is injected in inside, a steel pipe(140) which is inserted in nail in order to be positioned in the forecast activity surface of four sides and is slid, an urethane injection hose(150) which is installed so that urethane be injected in packer, a grout injecting hose(160) for injecting the grout into the perforation hole, an air exhaust hose(170) taking good care of the air within the perforation hole with exhaustion, a pressing plate(180) inserted in the head of nail, a nut(190) which adheres the anchor plate closely to four sides of the perforation hole surrounding and fixed.

Description

Slope reinforcement nails {SOIL-NAIL FOR REINFORCING A SLOPE}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a soil-nail used in a soil-nailing method, and more particularly, to a slope through pressure grouting and introduction of a pre-tension to a nail. The present invention relates to a slope reinforcement nail that has excellent resistance to sliding and strengthens shear resistance, bending resistance and pullout resistance to cope with the shear force generated in the expected activity of slope.

In Korea, which has a narrow land and many mountainous areas, it is essential to develop slopes with large-scale land construction, road construction, and railway construction. However, due to the inhomogeneous distribution of soil and rock, slopes can be collapsed due to natural disasters such as heavy rains and earthquakes, or it can be anxious to lose valuable lives and property due to sliding.

Therefore, a variety of slope reinforcement methods for stabilizing slopes have been developed and applied in civil works. In particular, the soil nailing method is a method using the shear resistance of the nail, as shown in Figure 4a to insert the nail 110 into the ground of the slope at a relatively tight interval to increase the overall shear strength of the ground itself, It is a construction method that not only suppresses the displacement of the ground expected during and after construction, but also suppresses the ground activity in the expected activity surface (a) of the slope.

Conventional construction methods of the soil nailing method first excavate the slope to form a drill hole with a downward slope of about 10 ° ~ 20 °. Next, after the nail is inserted, cement grout is filled and solidified to form a nail structure, and the nail is fixed to the slope using a pressure plate and a nut. At this time, shotcrete may be placed on the front of the slope where the nail is installed.

As a prior art of a soil nail used in the soil nailing method, a "pressure-type soil nailing packer" of the Utility Model No. 290351 is disclosed. According to this, the packer is installed on the head side of the nail, and the foaming urethane chemical is injected and cured into the packer to grout at a high pressure through the grout injection hose installed in the nail in a state of completely sealing the perforation hole. This increases the effective diameter of the grout solidified body has the advantage of improving the resistance to the pull out of the nail and the activity of the slope.

Further, as a prior art of small nails, a "pretensioned nail structure" of registered utility model No. 359052 is disclosed. According to this, a sheath pipe is installed on the nail so that a part of the nail is not settled by cement grout, and a tension is introduced to the nail. As a result, passive earth pressure is induced inside the front wall of the slope, so that the shear strength of the surrounding ground is increased, and the resistance to the activity of the slope is improved.

However, while the small nails according to the prior art are beneficial to improve the resistance to the activity of the slope, excessive shear force occurs in the expected active surface (a) of the slope reinforced with nail 110 as shown in Figure 4b Compared to the nail (110) lacks the shear resistance of the nail itself due to the lack of shear resistance (a), the nail 110 is broken, or the deflection resistance and pull-out resistance is insufficient to be bent or pulled in the direction that the slope flows down easily. Loss of resistance to slope activity occurs. As a result, the small nail according to the prior art has a problem in stabilizing the slope due to the lack of shear resistance, bending resistance and pull resistance of the nail to the shear force generated in the expected activity of the slope.

The present invention has been made for the above problems, and an object of the present invention is to provide a slope reinforcement nail that strengthens the shear resistance, bending resistance and pull resistance of the nail to the shear force generated in the expected activity surface of the slope.

Other objects, specific advantages and novel features of the present invention will become more apparent from the following detailed description and preferred embodiments in conjunction with the accompanying drawings.

In order to achieve the above object, the slope reinforcing small nail according to the present invention has a rod-shaped nail inserted so that the head is exposed to the perforated hole drilled on the slope, and the outer peripheral surface of the nail having a predetermined length from the head of the nail. It has a sheath tube covering, the annular packer is installed in the nail so as to be located at the entry end of the drilling hole and the urethane chemical is injected therein and in close contact with the drilling hole, and has an inner diameter larger than the outer diameter of the sheath tube. Steel pipe that is inserted into the nail and slides so as to be located on an expected active surface of a slope, a urethane injection hose installed to inject the urethane into the packer, and grout injection installed through the packer to inject grout into the drilling hole. An air discharge hose installed through the hose and the packer, and the air discharged from the drilling hole And the jiappan to be fitted to the head of the jiappan four days, and the tensile force in four days even after purchased, characterized in that it comprises a nut for fixing by adhesion the surfaces around the perforations.

Slope reinforcing small nail according to the invention preferably further comprises a steel pipe fixing member for fixing the steel pipe located on the expected active surface of the slope to the nail.

In addition, in the reinforcement small nail according to the present invention, the packer comprises two packer plates to be spaced apart from each other and fitted to the nail, a cylindrical cloth member with both ends open, and both ends of the cloth member It is preferable that it is comprised by the fixing ring fixed to each packer plate.

In addition, the slope reinforcing small nail according to the present invention preferably further comprises a plate-shaped pull-out resistor that is fitted and fixed to the nail so as to be located at the entry end of the drilling hole. Furthermore, it is preferable that the nail further includes a plurality of spacers installed on the outer circumferential surface of the nail so as to maintain a constant distance from the drilling hole.

Slope reinforcement nail according to the present invention has the advantage that the shear resistance, bending resistance and pullout resistance to the activity of the slope is enhanced by having a steel pipe that can fully cover the expected active surface of the slope.

In addition, the slope reinforcement small nail according to the present invention is provided with a packer pressure grouting, there is an advantage that the resistance to the activity of the slope is improved by introducing a tension force to the nail.

The object of the present invention and the configuration, operation and effect of the present invention to achieve the same will be more clearly understood by the following detailed description of the preferred embodiment of the present invention with reference to the accompanying drawings.

1 is a cross-sectional view showing the structure and operation of the slope reinforcing small nail according to the present invention, Figure 2 is a front view showing the first packer plate of Figure 1, Figure 3 is a description for explaining the operation of the steel pipe of Figure 1 It is also.

Slope reinforcing small nail according to the present invention is nail 110, sheath tube 120, packer 130, steel pipe 140, urethane chemical injection hose 150, grout injection hose 160 And an air discharge hose 170, a pressure plate 180, and a nut 190.

Nail 110 has a rod shape. The nail 110 preferably has a length sufficient to be installed to extend beyond the expected active surface (a) of the slope to prevent the activity of the slope. In addition, the nail 110 is excellent in shear resistance, it is preferable to use a deformed reinforcing bar with good pull resistance so that the outer circumference is not easily drawn from the ground of the slope.

It is preferable that the drawing resistor 200 is installed at the distal end of the nail 110 corresponding to the opposite side of the head 112 of the nail so that it is not easily pulled out from the ground of the slope. In addition, it is preferable to install the plurality of spacers 210 on the outer circumferential surface of the nail 110 so that the nail 110 can be inserted at a predetermined interval in the drilling hole 130.

The nail 110 is inserted so that the head 112 of the nail is exposed to each of the plurality of perforation holes 103 drilled downward on the inclined slope 101. The nail 110 is stabilized by the cement grout is injected later to form a nail structure to prevent the activity of the slope to stabilize the slope.

The sheath tube 120 is a pipe member installed to cover the outer circumferential surface of the nail 110 to a predetermined length from the head 112 of the nail in order to introduce tension to the nail 110. As the sheath tube 120 is installed, the nail 110 is not covered with the sheath tube 120 as shown in FIG. 1, and the fixing unit 116 and the sheath tube 120 which are fixed by the cement grout injected thereafter. ) Can be divided into free parts 114 which are not covered by cement grout. The sheath tube 120 uses a plastic pipe generally used, and preferably has a length of about 2 to 3 M to introduce sufficient tension to the nail 110.

The method of introducing the tension force to the nail 110 is by injecting cement grout into the punching hole 103 and pulling and pulling the head 112 of the nail using a tensioner after the fixing unit 116 of the nail is fixed. Tension force is introduced to the part 114. After the tension force is introduced, the tension force introduced is maintained by fastening the acupressure plate 180 and the nut 190 to the head 112 of the nail. At this time, it is also possible to introduce a more stable tension by installing the welded wire mesh and shotcrete on the front of the slope 101 before introducing the tension force. By introducing the tension force in the day 110, the passive earth pressure is induced inside the ground of the slope to increase the shear strength of the surrounding ground, it is possible to improve the resistance to the activity of the slope.

The packer 130 is installed to inject cement grout at high pressure into the drill hole 103 into which the nail 110 is inserted. The packer 130 is installed at the nail 110 to be positioned at the entrance end of the drilling hole 103, and is injected into the foamed urethane chemical solution so that the packer 130 is in close contact with the drilling hole 103 so that the drilling hole 103 is sealed. do. Therefore, high pressure injection of the cement grout into the drilling hole 103 enables pressure grouting. The effective diameter of the grout consolidation body 220 is increased through the pressure grouting, and thus, the pull resistance of the nail and the resistance to slope activity are improved.

At this time, the packer 130 is spaced apart from each other two packer plate (132, 132 ') to be fitted to the nail 110, both ends of the cloth member 137, and both ends of the cloth member 137 It is preferable that the fixing ring 138 is fixed to each of the two packer plate (132, 132 '). FIG. 2 is a front view illustrating the first packer plate 132 of FIG. 1. Referring to this, the first packer plate 132 is formed with a first through hole 133 at the center thereof so as to be fitted into the nail 110. have. In addition, the second through-hole 134 for the urethane chemical injection hose 150 is inserted, the third through-hole 135 for inserting the grout injection hose 160 and the air discharge hose 170 for insertion Four through holes 136 are formed. In addition, the second packer plate 132 ′ is not formed with the second through hole 134 for the urethane chemical injection hose 150 to be inserted in comparison with the first packer plate 132. It is. The first, second, third, and fourth through holes of the packer plates are preferably finished with a sealing material to prevent the urethane chemical injected into the packer 130 from escaping out of the packer 130. . The cloth member 137 of the packer uses a nonwoven fabric, and both ends of the cloth member 137 are fixed to the grooves formed on the outer circumferential surfaces of the two packer plates 132 and 132 'by the fixing ring 138.

The steel pipe 140 has an inner diameter larger than that of the sheath pipe 120 as shown in FIG. 1, and is slid into the nail so as to be located at the expected active surface (a) of the slope. In order to install the steel pipe 140, the expected activity surface (a) of the slope should be calculated in advance. The expected active surface (a) of the slope can be obtained by calculation according to conditions such as the slope of the slope and the condition of the ground. As shown in FIG. 3, the steel pipe 140 is positioned in the nail 110 and inserted into the drilling hole 103 so as to sufficiently cover the expected active surface a of the slope obtained by the calculation. At this time, the small nail preferably further comprises a steel pipe fixing member 142 for fixing the steel pipe 140 located on the expected activity surface (a) of the slope to the nail (110). The steel pipe fixing member 142 may be inserted into the nail 110 to fix the steel pipe 140, or may be fixed by welding.

The nail is sheared, bent or pulled by shear force concentrated at the expected activity surface (a) of the slope by the steel pipe 140 installed in the nail 110, thereby preventing the loss of resistance to the activity of the slope. .

Urethane chemical injection hose 150 is a hose in which the urethane chemical is injected into the packer 130 installed in the nail (110). As shown in FIG. 2, it is fitted into the second through hole 134 formed in the first packer plate 132 and installed in the packer 130. The urethane chemical solution is injected through the urethane chemical injection hose 150 so that the cloth member 137 of the packer expands to be in close contact with the punching hole 103. The injected urethane chemical has a very short curing time and has a characteristic of increasing volume upon curing. Therefore, when the injected urethane chemical liquid is cured, the urethane chemical liquid solid body 230 of FIG. 1 is formed to seal the perforation hole 103, and pressure grouting is possible.

 The grout injection hose 160 is installed through the packer 130 and is a hose into which cement grout is injected after the urethane chemical solid solution 130 is formed. The grout injection hose 160 is installed in the packer 130 to be inserted into the third through hole 135 of the first packer plate and the second packer plate to extend to the fixing unit 116 of the nail. High pressure spraying the cement grout through the grout injection hose 160, the grout solidified body 220 is formed when the injected cement grout is cured.

The air discharge hose 170 is installed through the packer 130 and is a hose through which the air in the drilling hole 103 is discharged when cement grout is injected. The air discharge hose 170 is installed in the packer 130 to be inserted into the fourth through hole 136 of the first packer plate and the second packer plate to extend to the fixing unit 116 of the nail. Therefore, the cement grout can be easily injected by discharging the air in the drilling hole 103 during grouting.

The acupressure plate 180 and the nut 190 are for introducing a tension force to the free portion 114 of the nail when the cement grout injected into the drilling hole 103 is cured to form the grout consolidation body 220. That is, when the tension plate 180 is pulled by pulling the head 112 of the nail using a tensioner in the state of being inserted into the head 112 of the nail, tension is introduced into the free portion 114 of the nail, and the pressure plate 180 is When the nut 190 is fastened to be tightly fixed to the slope 101, the tension force introduced into the nail 110 may be maintained.

An embodiment of the present invention described above and illustrated in the drawings should not be construed as limiting the technical idea of the present invention. The scope of protection of the present invention is limited only by the matters set forth in the claims, and those skilled in the art can change and change the technical idea of the present invention in various forms. Therefore, such improvements and modifications will fall within the protection scope of the present invention as long as it will be apparent to those skilled in the art.

1 is a cross-sectional view showing the structure and operation of the slope reinforcing small nail according to the present invention,

FIG. 2 is a front view illustrating the first packer plate of FIG. 1,

3 is an explanatory diagram for explaining the operation of the steel pipe of FIG.

4 is an explanatory diagram for explaining a problem of a small nail according to the prior art.

<Description of the symbols for the main parts of the drawings>

101: slope 103: drilling hole

110: nail 112: tofu

114: free part 116: fixing unit

120: Sheath Hall 130: Packer

132: first packer plate 132 ': second packer plate

133: first through hole 134: second through hole

135: third through hole 136: fourth through hole

137: cloth member 138: retaining ring

140: steel pipe 142: steel pipe fixing member

150: urethane chemical injection hose 160: grout injection hose

170: air discharge hose 180: pressure plate

190: nut 200: drawing resistor

210: spacer 220: grout solidified body

230: Urethane chemical solidified body

Claims (5)

A rod-shaped nail inserted to expose the head to a perforation hole drilled on a slope; Sheath tube having a certain length from the head of the nail, covering the outer peripheral surface of the nail, An annular packer installed on the nail to be positioned at the entrance end of the punching hole and expanding when urethane chemical is injected into the nail to closely contact the punching hole; A steel pipe having an inner diameter larger than an outer diameter of the sheath pipe and being slid into the nail so as to be located at an expected active surface of the slope; Urethane injection hose is installed so that the urethane is injected into the packer, A grout injection hose installed through the packer to inject grout into the hole, An air discharge hose installed through the packer and through which air in the drilling hole is discharged; Acupressure plate fitted to the head of the nail, Slope reinforcement nails including a nut for fixing the pressure plate in close contact with the periphery around the perforation hole after introducing the tension force to the nail. The method of claim 1, Slope reinforcement nails characterized in that it further comprises a steel pipe fixing member for fixing the steel pipe located on the expected activity surface of the slope to the nail. The method of claim 1, wherein the packer, Two packer plates spaced from each other and fitted to the nail, Cylindrical cloth member which is open at both ends, Slope reinforcement nails, characterized in that consisting of a fixing ring for fixing both ends of the cloth member to each of the two packer plate. The method of claim 1, Slope reinforcement nails characterized in that it further comprises a plate-shaped pull-out resistor is inserted into the nail so as to be located at the entrance end of the drilling hole. The method according to claim 1, wherein Slope reinforcement nails characterized in that it further comprises a plurality of spacers installed on the outer circumferential surface of the nail so that the nail maintains a constant distance with the drilling hole.

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