KR20100081676A - Soil nail including a plurality of foldable scales - Google Patents

Abstract

PURPOSE: A soil nail with a plurality of foldable scales is provided to ensure high pull-out resistance to a cut embankment surface and thereby reduce noise and vibration during construction. CONSTITUTION: A soil nail comprises a core, an outer sheath, scales(24), and a bent portion(22). The core is formed of reinforced plastic or metal. The outer sheath is formed of synthetic resin for covering the core. The scales are alternately formed between a leading end(12) and a tail end(14). The bent portion is formed on an edge of the scale.

Description

SOIL NAIL INCLUDING A PLURALITY OF FOLDABLE SCALES}

The present invention relates to a saw nail used to reinforce the slope of cut soil, and more specifically, to a saw nail that can maximize the pull resistance with the base using a plurality of scales formed on the outer peripheral surface.

Soil nailing method is to be able to resist the earth pressure of the back surface of the reinforcing structure by configuring a part of the soil of the excavation surface as one large reinforcement. Therefore, the Soil Nailing Structure formed by the Soil Nailing Method externally supports the back earth pressure on the same principle as the gravitational soil structure, and internally the reinforcing material nail (rebar) and the surroundings of the nail Interaction with the ground forms a local resistance system.

The Soil Nailing Method is similar to the Reinforced Earth method in the concept of forming a reinforcement composed of a mass of soil and reinforcement by reinforcement materials installed at regular intervals in the ground. The material is different from the standardized reinforced earth process. In particular, the biggest difference between the two is that, in terms of construction, the sawing nailing is a series of reinforcement work from the top to the bottom through the pit or cut process, while the reinforcement method is the method of reinforcing from the bottom up Therefore, even in the same cross section, the generated displacement and the stress distribution show a considerable difference.

Soil nailing is to excavate the slope or excavation surface to a stable height, and at the same time, to install the surface protection hole with shotcrete, and to drill the reinforcement on the excavation back ground by drilling or other methods. The reinforcement soil is formed by simple operation.

Ground excavation to install front guards and stiffeners is essentially the same as general ground excavation. However, in the case of saw nailing, the excavation surface is often used as a main body structure, so it is necessary to excavate to the exact position and shape, and the excavation depth, injection grout or shockcrete that the ground can stand on depending on soil quality In consideration of the curing period to obtain the predetermined strength, the depth of excavation and the timing of the next excavation should be determined.

Excavation is carried out to the middle between the nail and the nail to be installed. If there is an aquifer or non-adhesive sand layer in the middle of the strata, or if it is difficult to stand on its own, it can be solved to some extent by using a method of inserting a reinforcement or placing a jaw in advance, or using a ready-made panel. The stop line of the excavation ground is excavated flat and perpendicular to the wall. If part of the excavated wall surface is collapsed during excavation, if the surface treatment is performed by spraying with shockcrete, the amount of shockcrete will be increased. So, put the soil on the sack and accumulate on the collapsed part, and spray on it. Is effective.

Drilling is used to install reinforcement materials, such as rock drills and boring machines. Most drilling is carried out using fluids (air, water, nissu, cement grout, bentonite).

The choice of fluid during drilling is very important in terms of the prevention of wall collapse. Wet perforations should be avoided, except in special cases (rocks, areas of collapse). Impact perforations are, in principle, used for solid soils, but in fact they can also be used for hard soils, and have proven to be applied to soils that have limited utility due to the nature of the soil. Impact rotary drilling can be used independently or in combination of the impact force and rotational force, respectively. This method has a wide range of applicability and is therefore the most frequently used method for non-homogeneous or changeable soils.

For drilling, there is a method of drilling immediately after excavation of the ground and a method of drilling after shoveling concrete for stability of the excavation ground. The reinforcement is inserted into the reinforcement after drilling in a tight ground such as rock, and grouting, but it is difficult to install or grout the reinforcement in the collapsible ground, because the self-supporting wall is difficult. In such decayed grounds, casings are used to prevent the collapse of hollow walls, or special self-supporting boring machines designed for application to decayed grounds are used.

After drilling, the inside of the hole must be cleaned. At this time, the wall of the hole may be scoured, so water should not be used except in special cases such as viscous soil. Casing may be used in the case where the minimum wall maintenance is difficult, but the casing is economically removed by injecting grout. When drilling, pay attention to the position, spacing, diameter, depth, etc. of the drilling to ensure a predetermined degree.

Nails used for saw nailing may use deformed steel or other steel rods that can be used as nails, and any harmful soil or oil on the grout and the parts to be attached should be removed in advance. Nails used in permanent structures must take into account the allowance for corrosion or use rust-treated steel. It is recommended that nails be used as they are without seamless seams, but if the insertion length is unavoidable and inevitably connected, the coupler should be used and should not be connected by normal welding. When inserting a nail, spacers should be used to ensure that the nail is centered in the drilled hole to ensure the minimum thickness of the grout.

In the case of installing the nail and grouting, grouting cement milk into the life of the lifelessly in the usual case and installing the casing, when recovering the casing, the wall of the hole does not collapse before it is completely hardened after grouting. The casing should be removed.

The grouting shall be made to completely fill the inside of the hole and should be carried out three to six times depending on the tendency of the grouting material to penetrate the surrounding ground. The more dry soils, the better the number of injections. Finally, a cloth or stopper should be inserted to prevent the grout from overflowing from the hole entrance.

At least two injection hoses are installed, and the end of the primary injection hose is positioned at the bottom of the drilled hole, and the other hose is positioned at about 3/4 of the length of the hole at the hole entrance. Is carried out.

At the time of injection of the grout, the injection pipe is extended from the bottom to the bottom of the hole, and when the grout is filled, the injection pipe is slowly pulled out to the end of the excavation surface. In order to minimize the collapse of the inside of the wall of the hole, the injection of grout is carried out after the nail is installed.

The first injection is performed until the injection material flows from the bottom of the hole to the inlet of the hole, and every 2 to 4 hours, the second to fifth injection is made, and the final injection is made at the hole inlet.

At the end of the grouting operation, it takes at least one week for the curing period to achieve the desired strength, so care must be taken not to apply tension or impact to the nail within this period.

If nailing is applied as a permanent structure, increase the thickness of the shockcrete face plate that is constructed in a temporary form at the time of construction, or install a reinforced concrete structure thereon.

Shockcrete used for surface protection is adjusted to the strength or hardening time by changing the formulation according to the geological or construction conditions, and the construction thickness of the shockcrete is usually 7 to 15cm, and if necessary, reinforcing materials such as wire mesh or steel can be used. Also used. The method of hitting the shockcrete may be performed by dividing the first and the second, or the thickness of the designed shockcrete at once.

The method of hitting the shockcrete by dividing the first and the second is a method of hitting the first shockcrete with a thickness of 7.5 to 10 cm, followed by a wire mesh, a pressure plate, and bolting, and then hitting the shockcrete having a thickness of 7.5 to 10 cm. In this case, since the pressure plate and the nut are embedded in the shockcrete, the horizontal reinforcing bars serving as a wale beam are also connected before hitting the secondary shockcrete. One-time construction is a method of spraying shockcrete at a time by installing a wire mesh at a position 1/2 of the thickness of shockcrete on an excavation wall after grouting.

Except in special cases the device for nail installation is provided with a metal support plate and a threaded nut. The pressure plate uses roughly 150 × 150 × 12mm steel plate. Tighten the bolts by hand when installing and bolting the pressure plate immediately after the injection of shockcrete. After curing for about a day, use a wrench to reach the predetermined strength. Tighten firmly.

If a wall structure is additionally installed on the shockcrete as a permanent structure, a steel bar of about 15 to 20 cm should be welded to the four corners of the pressure plate to further support the load of the faceplate, or the protruding head of the nail should be further protruded. .

As described above, the method of reinforcing the cut soil slope using a conventional saw nail has to go through ground excavation, drilling, reinforcing material insertion, grouting, and faceplate installation, so that the air is long and expensive. Have

Therefore, the present invention is to solve the problem in the method of reinforcing cut soil slope using the conventional saw nail, the slope reinforcement nail that can shorten the air by eliminating the ground excavation, drilling and reinforcement insertion process The purpose is to provide.

Another object of the present invention is to provide a slope reinforcing nail that can maximize the pull resistance of the nail without disturbing the base.

In order to achieve the above and other objects of the present invention, according to an embodiment of the present invention, in the saw nail for reinforcing the slope of the cut soil having a front end and a distal end, a core made of plastic or metal, A sheath nail including a sheath made of a resin covering the core and having a plurality of scales alternately formed between the front end and the distal end, and a bent portion provided at one corner of the upper end of the scale.

The scale is formed by cutting a predetermined width of the outer circumferential surface of the housing, and a recess corresponding to the scale is formed on the outer circumferential surface of the housing.

The scales are provided in pairs on the outer circumferential surface of the enclosure, and a plurality of pairs of scales are alternately installed along the longitudinal direction of the enclosure.

Preferably, the distal end is formed with a screw portion to fix the pressure plate or coupler.

The exterior is preferably made of any one of polyethylene (PE), polypropylene (PP), polyester (PET), PVC.

According to the above-described configuration, the pull nail resistance of the present invention is maximized by rotating the saw nail of the present invention on the slope of the cut soil, thus eliminating construction such as ground excavation, drilling, and reinforcement insertion. It can be shortened.

In addition, since the slope of the cut soil is not punctured, the generation of noise and vibration during construction can be greatly reduced. In addition, since a large number of saw nails can be installed at relatively close intervals, even if the pull-out resistance of some saws is weakened or broken, there is an effect that the overall stability does not occur.

Hereinafter, a slope reinforcing nail according to a preferred embodiment of the present invention with reference to the accompanying drawings will be described in more detail.

1 is a schematic diagram showing a state in which the reinforcing nail is installed according to a preferred embodiment of the present invention, Figure 2 is a schematic diagram showing a state before the reinforcing nail shown in Figure 1 is installed.

Slope reinforcing nail 10 according to the present invention is a core (C) made of reinforced plastic or steel, and the high-density polypropylene (HDP), polyethylene (PE), polypropylene (PP), which surrounds the steel core, It is composed of a sheath (S) made of any one of polyester (PET), PVC. The sheath is preferably provided as a coating on the core to prevent moisture from penetrating between the core and the sheath.

Slope reinforcing nail 10 is connected to the front end portion 12, the threaded end portion 14, the front end portion 12 and the distal end portion 14, the plurality of scales 22 And shanks 16 with 24 alternately provided. The points and scales 22 and 24 constitute part of the sheath, and are therefore made of the same material as the sheath.

The scales 22 and 24 are provided one by one on the outer circumferential surface of the shank portion 16, and the installation direction of the scale 22 is alternately arranged at 90 degrees with the installation direction of the scale 24. At the upper left corner of each of the scales 22 and 24, a bent portion 22 folded at a predetermined angle is formed. The number of scales 22 and 24 provided on the shank portion 16 is determined according to the length of the nail to be shot.

The scales 22 and 24 are formed of the same material as the material of the shank portion 16 (HDP or LDP in this embodiment), and thus have some flexibility. The scales 22 and 24 are formed by cutting a part of the sheath S at an angle with a constant width, and a recess 26 is formed in the sheath S corresponding to the scale. The upper ends of the scales 22 and 24 are separated from the recessed part 26 of the exterior in the free end state, and the lower end part is integrally connected with the lower part of the recessed part 26.

After the saw nail 10 of the present invention is installed on the slope of the cut soil, friction occurs between the bent portion 22 and the soil around the saw nail when the saw nail 10 is rotated clockwise. Therefore, when the saw nail 10 is continuously rotated, the scale is unfolded like a wing as shown in FIG. 1 by the resistance of the bent portion 22. When the plurality of scales 22 and 24 are alternately inserted into the base, alternating resistance of the nail to the base can be maximized.

As described above, the nail nail 10 according to the present invention has a threaded portion of a predetermined length formed at the distal end thereof. After the nail nail 10 is installed on the slope of the cut soil, the coupler 30 is attached to the distal end 14, and the hexagon nut 36 is fastened to the threaded portion (see FIG. 3).

Hereinafter, a method of reinforcing the slope of cut soil using the nail nail 10 according to the present invention will be described.

First, the plurality of saw nails 10 are formed at predetermined intervals on the slopes of the cut soil to be reinforced. The nail nail 10 typed to a predetermined depth is rotated in a clockwise direction, and the coupler 30 serving as a pressure plate is mounted on the distal end portion 14 of the nail nail 10, respectively.

If necessary, the steel rod or rope 34 may be sequentially inserted into the slots 32 formed on the bottoms of all the couplers 30 to further reinforce the slope of the cut soil.

After attaching the coupler 30 to the distal end 14 of the nail 10, the hexagon nut 36 is firmly fastened to the threaded portion of the distal end 14 exposed from the coupler 30 to the outside.

After hitting the shockcrete with a predetermined thickness on the slope of the cut soil, the coupler 30 and the hexagon nut 36, and curing for a predetermined period, the slope reinforcement work of the cut soil is completed.

In the above-described process, when the saw nail 10, which is typed on the slope of the cut soil, is rotated in the clockwise direction, the bent portion 22 formed at the upper left of the scales 22 and 24 causes friction with the soil around the nail to be shot, Scales 22 and 24 are automatically unfolded in the disc.

According to the structure of the saw nail of the present invention described above, since the slope of the cut soil is not punctured, it is possible to greatly reduce the occurrence of noise or vibration during construction. In addition, since a large number of saw nails can be installed at relatively close intervals as compared to a conventional saw nail, even if the pull-out resistance of some saws is weakened or broken, there is an effect that the overall stability does not occur.

While the present invention has been described with reference to preferred embodiments, the present invention is not limited or limited to the above-described embodiments. Those skilled in the art will appreciate that various changes or modifications are possible within the scope of the appended claims. The protection scope of the present invention is determined by the appended claims.

Figure 1 is a schematic diagram showing a state in which the saw nail for reinforcement is installed in accordance with a preferred embodiment of the present invention.

Figure 2 is a schematic diagram showing a state before the reinforcing saw nail shown in Figure 1 is installed.

3 is a perspective view showing a coupler mounted to the distal end of the saw nail of the present invention.

Claims (4)

In the saw nail for reinforcing the slope of the cut soil having a front end and a distal end, A core made of any one of reinforced plastic and metal; It includes an exterior made of a synthetic resin covering the core, A saw nail, characterized in that a plurality of scales are alternately formed between the front end and the distal end, and a bent portion is provided at one corner of the upper end of the scale. The method of claim 1, The scale is installed in the left and right pairs on the outer circumferential surface of the exterior, the nail nail characterized in that a plurality of pairs of scales are alternately installed along the longitudinal direction of the exterior. The method of claim 1, Soil nail, characterized in that the end portion is formed with a screw portion for fixing the pressure plate or coupler. The method of claim 1, The exterior nail is a nail nail, characterized in that made of any one of polyethylene (PE), polypropylene (PP), polyester (PET), PVC.

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