JP2011099317A - Method for embedding anchor for preventing rockfall - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for embedding an anchor for preventing a rockfall, which can sufficiently and uniformly bear the earth pressure of the peripheral area and stably cope with tensile forces from multiple directions. <P>SOLUTION: When vertical and horizontal ends and cross points of wire ropes stretched across the length and breadth in a net-like form along the ground surface of a slope 2 are fixed to the ground, vertical and horizontal strings are stretched at required intervals along the ground surface of a predetermined construction place. The cross points of the vertical and horizontal strings are set as an installation place of the anchor, a right-angled direction to the ground surface is measured in at least two directions at the cross points, and then required pipe anchors 3 are driven in the right-angled direction to an vertically inclined surface using the measured angles as a reference line. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a rock fall prevention anchor burying method in a rock fall prevention facility laid on a slope.

On slopes with scattered rocks, etc., there is a risk of rocks falling due to weathering of slopes, erosion of slopes by running water, earthquakes, etc., and causing a serious accident by directly hitting roads and houses below.
As a countermeasure, in Japanese Patent No. 2679966, the wire rope is laid so that the nets are vertically and horizontally meshed so as to be in close contact with the ground surface of the slope, so that the floating stone is pressed against the ground surface, the falling energy of the floating stone is absorbed, and the stone is stationary. A construction method is disclosed.

In this method, the top, bottom, left, and right ends of the wire rope are fixed to the ground with anchors, the crossing portions of the wire rope are fastened with clips, and the required wire rope crossing portions are fixed to the ground of the slope with the anchors, In the above prior art, a method is adopted in which the anchor is formed by digging holes in a plurality of locations on the slope, filling the solidified material, and inserting and fixing the anchor, and therefore it takes time to solidify the filler and the cost is high. In addition, there is a problem that the yield strength varies because the optimum driving angle and direction with respect to the slope are not disclosed.

If the slope where the anchor is to be installed is not rock, but soil, gravel, or stone, the pipe anchor is suitable, and the anchor is driven into the intersection of the mesh rope. It was common to install it perpendicularly to the road cross section.
However, since pipe anchors gain bearing capacity due to the surrounding earth pressure, embedding perpendicular to the earth's axis is greatly affected by the soil quality and volume of the front (valley side), and there are irregularities in the target slope. Alternatively, when there is a notch slope that is similar to a swamp, the amount of earth and sand on the valley side decreases corresponding to the swollen slope, so the earth pressure around the pipe is not uniform.

In addition, because of the peculiarity of the rope fall prevention net that crosses the rope vertically and horizontally, the anchor has an upward, downward, leftward, rightward or a combined pulling force through the rope. Since it works, if it is driven in the vertical direction with respect to the earth's axis as before regardless of the topography of the slope, the earth pressure on the top, bottom, left, and right becomes uneven and the tensile force from below is proof, but the upper or There was a problem that sufficient earth pressure resistance was not guaranteed for pulling from the left and right.
Japanese Patent No. 2679966

  The present invention has been made in order to solve the above-described problems, and the object of the present invention is to sufficiently and uniformly receive the surrounding earth pressure and to be stable against tensile forces from multiple directions. It is an object to provide an anchor burying method for falling rocks having the same proof strength in all directions.

  In order to achieve the above object, the present invention follows the surface of the planned site for fixing the vertical and horizontal wire ropes, which are stretched in a mesh pattern along the slope surface, and the ends of the right and left sides and the intersections on the ground. The vertical and horizontal yarns are stretched at the required intervals, and the intersection of the vertical and horizontal yarns is set as the anchor installation location. At the intersection, at least two directions are measured at right angles to the ground surface, and the required pipe with the measurement angle as the reference line. The anchor is driven at a right angle to a surface inclined in the vertical direction.

When an initial movement of a rock is started at one place, a tensile force is applied to the anchors on the top, bottom, left and right of the stone, and falling rocks often occur at multiple places at the same time. When fastening and holding the left and right ends and the intersection,
The vertical and horizontal yarns are stretched at the required intervals along the ground surface of the planned construction site, and the intersection of the warp and weft is set as the anchor installation location, and at least two directions are measured at right angles to the ground surface at the intersection. Since the pipe anchor is driven into the ground with the measurement angle as the reference line, the earth pressure against the anchor is equalized, and the same proof stress is obtained in all directions, up and down, left and right, preventing the movement of rocks and falling rocks stably and reliably can do.

Also, in measuring at least two directions perpendicular to the ground surface at the intersection, a tripod-shaped jig equipped with a guide pipe that penetrates the rod-shaped member in the center is used, so it can be accurately performed with simple operations. A right angle can be made in a 360 degree direction.

Embodiments of the present invention will be described below with reference to the accompanying drawings.
1 to 3 show an example of a rockfall prevention facility obtained by applying the present invention. In FIG. 1, RD is a road, 2 is a slope existing above the road RD, and FIG. As shown in the figure, floating stones ST are scattered, and standing trees WD are scattered. In this example, the slope 2 is adjacent to the first inclined area 2A and the first inclined area 2A, which is inclined with a component only in the vertical direction with respect to the road when viewed from the direction indicated by the white arrow. A second inclined region 2B in which a component inclined in the vertical direction and a component inclined in the horizontal direction are combined, and a third inclined region which is adjacent to the second inclined region 2B and is inclined with a component only in the vertical direction. 2C.
The second inclined area 2B indicates a lot of terrain, and the inclination in the left-right direction switches in the middle of the width direction, and the left area 2B1 that is higher as it approaches the first inclined area 2A, and the third inclination The closer to the region, the higher the right region 2B2. Note that the left region 2B1 and the right region 2B2 are not necessarily at the same inclination angle.

N is a rope net type rock fall prevention device according to the present invention, and is laid over the entire slope or the required range of the slope 2 where the floating stones ST and standing trees WD are scattered as described above. For example, the horizontal wire rope 1B is crossed so as to have a 2m square mesh shape, and is routed around the standing tree WD as much as possible, and is stretched along the terrain so as to pass over the floating stone ST.
The vertical terminal of each main vertical wire rope 1A and the horizontal terminal of each main horizontal wire rope 1B are fixed to the ground by anchors 3 and 3, respectively, and the intersection of the main vertical wire rope 1A and main horizontal wire rope 1B. Is fixed to the anchors 3 and 3 via a coupling fitting 4 such as a cross grip.

Between the main vertical wire rope 1A and the main horizontal wire rope 1B, a vertical auxiliary rope 10A and a horizontal auxiliary rope 10B having relatively small diameters are arranged as necessary, as shown in FIGS. 5 (d) and 5 (e). In this way, the intersecting portion is fastened by a coupling fitting 40 such as a cross clip or a cross grip. The main vertical wire rope 1A and the main horizontal wire rope 1B have a diameter of 14 mm, for example, and the auxiliary rope has a diameter of 12 mm. Both are made of a corrosion-resistant material, or are corrosion-resistant by surface treatment such as galvanization. Is given.

Of the anchors, when the target site is a rock, drill holes and insert an anchor body such as a deformed steel bar into the hole to solidify mortar or resin. In FIG. 3, it is shown as 3 '. However, when the target site is earthy and sandy, a pipe anchor configured by processing a pipe such as a steel pipe is used, and the vertical direction and the horizontal direction are respectively changed from the first inclined region to the third inclined region. It is buried at intervals of 2m.

In the present invention, the wire rope is located in the required range of the upper and lower, left and right end portions and crossing portion anchors 3, that is, in a region where a substantially equivalent proof stress is required in a 360-degree azimuth (thus all). However, it is not perpendicular to the cross section of the road 1 (perpendicular to the ground axis), and the first inclined region 2A and the third In addition to the inclined region 2C, the second inclined region 2B is embedded in a right angle in an orientation of 360 degrees with respect to the anchor installation target slope.
Here, “right-angled, substantially right-angled” means to include a case where it is not strictly 90 degrees with respect to the slope, and this must include an error in the measurement from the topography and work surface of the construction site. Because there is no. Although the allowable range of errors is not generally determined, it can be said that there is no problem in terms of proof strength if the range is usually 10 to 20 degrees.
FIG. 4 schematically shows the embedded state of FIG. 2, where L represents the anchor length, and in the first inclined area 2A and the third inclined area 2C, it is almost vertically with respect to the road when viewed from the front. Since it is inclined only by the direction component, each anchor 3 in this region has its axis buried in a right angle with respect to the normal inclination angle.

  In the second inclined area 2B, a component that is inclined in the vertical direction with respect to the road and a component that is inclined in the left-right direction are combined, and in the left area 2B1, the left and right anchors become higher as they approach the first inclined area 2A. It is embedded so as to be perpendicular to the inclination angle α in the direction and perpendicular to the inclination angle in the vertical direction. Since the vertical inclination angle here is smaller than that of the first region 2A, even if each anchor has the same length, the anchor of the left region 2B1 is apparently higher in the contour line viewed from the front. It is inserted. Since the right region 2B2 of the second inclined region 2B is higher as it approaches the third inclined region, the anchor is buried in contrast to the left region 2B.

As shown in FIG. 5 (a), each anchor 3 of the terminal has a ring portion of a winding grip 5 wound around the ends of the main vertical wire rope 1A and the main horizontal wire rope 1B on the head protruding from the ground surface. 50 is fitted externally and is prevented from coming off by a pin 30 penetrating the pipe.
Further, as shown in FIG. 5C, a cap 31 is fitted to each anchor 3 in the mesh region at a head protruding from the ground surface, and is fixed by a pin 30 penetrating the pipe. A bolt 32 for fixing a grip is planted on the cap 31, and a coupling metal fitting composed of oval boards 40 and 41 that form a pair at the top and bottom across the intersection of the main vertical wire rope 1A and the main horizontal wire rope 1B. One end of 4 is passed through the bolt 32 and tightened with a nut to be integrated with the anchor. The other end of the coupling fitting 4 is fastened with a bolt nut 33.

When the present invention is applied to all anchors, the mesh-like ropes 1A and 1B holding the float stone ST are always embedded at right angles to the slope angle at any inclination, The surrounding earth pressure is applied sufficiently and uniformly, and the same proof stress can be obtained in all directions.
Therefore, the same stable support force can be obtained in both the first inclined region and the second inclined region, and even if the floating stone ST moves and a multidirectional load is applied, it can be firmly received.
That is, since the crossing portion of the rope is fastened by the connecting metal fittings 4 and 40, when an initial movement of one rock falls at one place, a tensile force is applied to the upper and lower and left and right anchors of the stone. The force applied to these individual anchors varies depending on the terrain and the situation of rock fall, and rock fall often occurs simultaneously at multiple locations, and the force applied to the anchor 3 is complicated by the force of the rope. Since the anchor 3 is driven into the inclined surface at a substantially right angle, the equal strength is maintained in the vertical and horizontal directions, and rockfall can be reliably prevented.

  Since the slope component is compounded in the vertical direction and the horizontal direction, the anchor has not been embedded so as to form a right angle with respect to the inclination angle α in the horizontal direction. For this reason, the earth pressure is not uniform over the entire circumference of the anchor, and the anchor strength is different between the first inclined area 2A and the second inclined area 2B, and a sufficient rock fall prevention effect cannot be achieved. For this reason, it was difficult to expect a sufficient effect even if the rockfall prevention device N was installed in a swamp where there is a sufficient risk of rockfall, but according to the present invention, it is almost equivalent to an anchor other than the swarm area. Strength anchors can be installed in many areas, and can be stably supported even when a falling rock is applied by a rope net.

The construction of the anchor does not prohibit the adoption of a conventional method of hitting and driving a pipe anchor from behind, and this method may be adopted when the soil has almost no gravel, In geology where gravel is expected to exist, in the striking method that adjusts the direction of driving manually, when the stone is buried in the soil in the anchor driving direction, the anchor driving direction is shifted by the stone, Since the earth pressure in the rope tension direction cannot be sufficiently obtained and the earth pressure on the upper, lower, left and right sides tends to be uneven, it is preferable to adopt a special anchor embedding device and construction method developed by the present applicant.
FIGS. 6 and 7 show an example suitable for the present invention, where 6 is a bit independent of the pipe anchor 1, 7 is a hammer portion 7 </ b> A for giving an axial striking force and rotational motion to the bit 6 and a rotation. The excavation assembly includes a shaft portion (rod portion) 7 </ b> B connected in series and connected to a bit 6.

Reference numeral 8 denotes a pedestal feed base installed at a construction site, which is provided with a main body 8A and a support 8B which are formed in a long rectangular frame shape so as to serve also as a guide rail, and the main body 8A is reversible for rotating the rotating shaft portion. A drive motor 9 as a rotatable excavator is slidably attached with a pedestal 9a, and a wire rope 100 from a winch 100A is connected to the pedestal 9a to suspend the drive motor 9. Reference numeral 100B denotes a winch that temporarily suspends the excavating assembly 7 and the anchor pipe when connecting to the drive motor 9. In this example, the drive motor 9 is a hydraulic motor, and includes a compressed air feed header 90 coaxially.

Reference numeral 11 denotes an air compressor disposed elsewhere, and is connected to a compressed air feed header 90 of the drive motor 9 via a hose 110. Reference numeral 12 denotes a hydraulic unit with a generator that supplies pressure oil to the drive motor 9, and has an operation panel 13 </ b> A including a control valve in the vicinity thereof, and is connected to the drive motor 9 through a hose 130. .
Reference numeral 14 denotes a water supply system used when the anchor embedding geology is clayey. The water supply system 14 has a water tank 14A and a pump 14B, and is connected to an appropriate place of the compressed air supply system by a hose 140.

FIG. 7 shows details of the pipe anchor 3 and the bit 6. The pipe anchor 3 has a length of 1500 to 3500 mm, for example, and is plated with zinc or aluminum zinc alloy.
The pipe anchor 3 has a hole for attaching a retaining pin (bolt) at the upper end portion, and the cap is crowned after being embedded. On the other hand, a propulsive force receiving portion 3B is integrally provided at the tip portion.
In this example, the propulsive force receiving portion 3B is made of a steel ring 3B. In the example of FIG. 7, the propulsion receiving portion 3B has an outer diameter substantially the same as the outer diameter of the anchor body 3A, and the inner diameter is smaller than the inner diameter of the anchor body 3A. The ring 3B is thinned from an appropriate position in the longitudinal direction so that the upper half 300 has an outer diameter that substantially matches the inner diameter of the anchor main body 3A, and the upper half 300 is fitted into the anchor main body 3A. The thick lower half 301 is extended from the tip of the anchor body 3A, and the boundary portion between the upper half 300 and the lower half 301 is welded to the anchor body 3A.

The bit 6 includes a bit head 6A in which a chip made of cemented carbide or the like is disposed on the end surface, and a housing (device) 6B in which a shaft-like portion 60 protrudes rearward. The bit head 6A is of an expandable / shrinkable type called an enlarged diameter bit. As an example, an eccentric type in which the diameter is increased during rotation in a predetermined direction and reduced in diameter in the opposite direction as illustrated in FIG. 7A may be used, or a multi-blade split type may be used, or FIG. (B) It may be a type that has a hook shape as shown in (c) and is locked by a rotatable piece attached to several places in the circumferential direction. In any case, a size that is equal to or smaller than the inner diameter of the ring 3B when the diameter is reduced and that can be appropriately larger than the outer diameter of the lower half of the ring 3B when the diameter is increased is selected.
At the rear end of the housing 6B, a collar portion 601 having an overhang amount capable of colliding with the end surface of the ring upper half 300 serving as the propulsive force receiving portion 3B is provided. The housing 6B is provided such that an axial groove 603 for guiding slime passes through the flange portion 601.

  The hammer portion 7A has a cylindrical shape, and the shaft-like portion 60 is connected to the tip portion so as to be integral with the rotation and relatively movable in the axial direction, and is movable between the hammer portion 7A and the housing 7B in the axial direction. It has become.

  The rotating shaft portion 7B has a pipe shape and is concentrically connected to the rear end of the hammer portion 7A. The rotation shaft portion 7B may have a required length by connecting a plurality of rotation shaft portions 7B. In any case, the rear end of the rotation shaft portion 7B is connected to the output shaft of the drive motor 9. Therefore, when the rotating shaft portion 7B rotates, the hammer portion 7A and the bit 6 are rotated synchronously. The compressed air supplied to the compressed air feed header 90 is sent to the hammer portion 7A through the rotary shaft portion 7B and acts on the piston portion in the shaft-like portion of the bit 6.

  The installation of the gantry 8 is arbitrary, and the support 8B may be fixed to the ground surface with the pin anchor 80. Further, if necessary, the upper portion of the gantry 8 may be supported on the ground surface with the holding rope 8C.

  The pipe anchor embedding method according to the present invention will be described. Normally, the pipe anchor 3 and the excavation assembly 7 including the bit 6 are in a separated state, and the excavation assembly 7 further includes the hammer portion 7A, the rotary shaft portion 7B, and the bit 6. Since it can be disassembled, it can be reduced in size and weight and can be easily carried into the site.

In burial, the location where the rock fall prevention device N on the inclined surface is laid is investigated, and the construction range Y consisting of the lateral width L and the longitudinal width H is determined as shown in FIG. Cut down the bush, etc., and arrange the construction range Y. Standing trees are not cut in principle, but if there is a possibility that the rope cannot be stretched in a mesh shape such as 2m square, the minimum cutting may be performed.
Next, as shown in FIG. 9, a strip TP such as a fiber rope, a flat braid, and a plastic tape is stretched in a rectangular shape so as to surround the construction range Y. The strip TP may be fixed by inserting a pin or the like into the ground. The upper and lower horizontal stripes TP1 and the left and right vertical stripes TP2 are marked, for example, at intervals of 2 m in the horizontal (left and right) direction and at intervals of 2 m in the vertical (up and down) direction. These marking positions become the terminal fixing anchor positions of the main vertical wire rope 1A and the main horizontal wire rope 1B.

Next, as shown in FIG. 10, a positioning warp HTP (fiber rope, flat braid, plastic tape, etc.) is hung from the marking position of the upper horizontal strip TP1 along the ground surface, and the lower horizontal stripe TP1 Stop at the marking position. At the same time, the weft LTP is extended along the ground surface from the left (or right) vertical stripe marking position and stopped at the right (or left) vertical stripe marking position. Accordingly, as shown in FIG. 12, the warp yarn HTP and the weft yarn LTP are stretched in a lattice pattern at intervals of 2 m in the transverse (left and right) direction and at 2 m intervals in the longitudinal (up and down) direction. The installation location of the anchor is determined.

Next, the anchor driving direction (driving angle) is determined for each anchor position ap determined in this way.
13 and 14 exemplify the first method for detecting and setting the driving direction of the 360 ° right angle anchor. The center length is the predetermined distance in the left and right direction and the predetermined distance in the vertical direction, for example, 1 m. Decide The horizontal direction and the vertical direction are equidistant. Then, a direction perpendicular to the intersection point a between the a1 ′ and a5 ′ lines in the left and right directions, for example, is detected and a pin is pierced into the ground, and the intersection a between the a3 ′ and a7 ′ lines in the vertical direction. On the other hand, a perpendicular direction is detected and a rod-like member is pierced in the ground, and the driving direction of the pipe anchor (substantially perpendicular to the surface) is determined with a direction satisfying both the horizontal and vertical directions. Such an operation is performed for each intersection ap.
The detection in the perpendicular direction may be performed with a ruler, a gyroscope, a slant, etc., and the warp and weft when determining the reference length are preferably along the ground surface in a tension state, and when the deviation from the ground surface is large, Make corrections.

  FIGS. 15 and 16 show a second method of detecting and setting the anchor driving direction. A folding tripod jig 15 is used as a tool, and the intersection (anchor center point ap) determined as described above is used. ) Around 360 ° direction right angle. The tripod-shaped jig 15 includes three legs 150 having a circumscribed circle radius of 1 m and equal leg lengths, and a centerline member having an inner diameter of about 20 mm to 30 mm hanging from the center of the top plate 151 fixed to the top end of the legs 150. The tripod-shaped jig top includes a guide pipe 152 that also serves as a slide, a slide 153 that is slidably fitted to the guide pipe 152, and an open / close bar 154 that is hinged to the slide 153 and the leg 150. The vertical height to the end is about 1 m. However, if the terrain unevenness of the construction site is extreme or has a sharp fold, correction such as reducing the circumscribed circle radius is performed.

  In detecting and setting the anchor driving direction, as shown in FIG. 16A, the center of the tripod-shaped jig 15 is installed so as to coincide with the intersection ap which is the center point of anchor installation. The installation direction (three directions) of the tripod-shaped jig 15 is arbitrary, and the guide pipe 152 that connects the center of the tripod-shaped jig 15 with the center of the ground plate from the center of the top plate of the tripod-shaped jig 15 is 360. Since it can be determined as a perpendicular direction, a rod-shaped member (for example, a pin made of round steel) 16 having a diameter of about 15 to 25 mm and a length of about 1.5 m and a sharpened tip is inserted into the guide pipe 152. Then, it is driven about 300 mm to 500 mm into the soil with a hammer or the like and is made independent as shown in FIG. Then, only the tripod-shaped jig 15 is pulled out as shown in FIG. As a result, the remaining rod-shaped member 16 becomes a reference line that is substantially perpendicular to the 360 ° direction. This is done for each intersection.

  When the anchor driving position and driving direction are determined as described above, the gantry (feed) 8 is installed. In both cases of the first method and the second method, it is installed along the rod-shaped member 16 which is a reference line. Since the anchor 3 is buried in the soil via the gantry 8, when the gantry is installed according to the reference line, it can be naturally installed in a direction perpendicular to 360 °. After the gantry is firmly installed with the rope 8C and the anchor 80 shown in FIG. 6, the bar-like member 16 serving as the reference line is pulled out and the anchor is installed. Although this will be described later, the error of the anchor driving angle is managed in the road crossing direction and the longitudinal direction, and if both directions are within about 10 to 20 degrees, it can be determined that the bearing has an equal strength in the 360 ° direction.

The angle management of the anchor 3 can be performed, for example, by using a slant or a ruler in the crossing direction of the road and a ruler in the longitudinal direction of the road. Good. Further, the error before and after the anchor installation may be managed at the fixed angle of the gantry based on the gantry.
In the present invention, the anchor driving direction detection / setting substantially perpendicular to the slope in the 360-degree azimuth and the installation of the anchor driving device are not limited to the above modes. That is, 1) The average slope of each 1m in the crossing direction (vertical rope) of the intersection ap where the anchor is installed is detected using a slant and a ruler, and the frame 8 is temporarily fixed. 2) After that, the road Alternatively, a method may be used in which the average gradient of 1 m left and right in the longitudinal (horizontal rope) direction is detected by a ruler, and the gantry 8 is slid in the left and right average gradient directions while maintaining the installation gradient of 1) above, and firmly fixed. The order of 1) and 2) above may be reversed. If there are extreme irregularities or sharp breaks, correct them according to the situation. In this case, the stick member need not be pierced.

If it is oriented substantially at right angles to the plane determined as described above, the drive motor 9 is mounted on the main body 8A of the gantry 8 and is suspended by the winch 10A and the rope 100, and the rotary shaft portion 7B and the hammer portion. The excavation assembly 7 assembled by connecting the 7A and the bit 6 is inserted from the rear end of the pipe anchor 3. At this time, the bit head 6A is rotated in the diameter reducing direction. Therefore, the bit head 6A descends through the pipe anchor 3 without resistance.

The virtual line in FIG. 17 shows the state at this time. For the sake of clarity, it is shown vertically in the drawing. If the bit head 6A protrudes from the lower end of the pipe anchor 3, the rotating shaft portion 7B and the hammer portion 7A are rotated. In this way, the bit head 6A is eccentric or substantially increased in diameter, and the whole or part of the bit head 6A expands to be equal to or larger than the outer diameter of the pipe anchor 3. Since the bit head 6A serves as a stopper, the pipe anchor 3 and the excavation assembly 7 are assembled together. Therefore, the whole is lifted using the winch 10B, and the rotating shaft portion 7B is connected to the drive motor 9. The preparation is now complete, and the drilling assembly will be fed under its own weight.

When the air compressor 11 is driven and compressed air is supplied to the header 90, the compressed air passes through the rotary shaft portion 7B and is press-fitted into the hammer portion 7A, and the shaft-like portion 60 of the bit 6 via the piston portion. Is strongly pressed in the axial direction, so that the bit 6 protrudes from the hammer portion 7A until the flange portion 601 of the housing 6B abuts against the ring end surface of the anchor, and therefore the bit head 6A is appropriately separated from the lower end of the ring 3B.
If pressure oil is supplied to the drive motor 9 by operating the operation panel 12A, the rotating shaft portion 7B rotates, the hammer portion 7A connected thereto rotates, and the bit 6 rotates via the shaft-shaped portion 60. To do. As a result, as shown in FIG. 17, the bit head 6 </ b> A rotates immediately in front of the pipe anchor 3, so that excavation and drilling of the formation is performed. At this time, since the flange portion 601 of the bit housing 6B is in contact with the ring end surface of the anchor, the pipe anchor 3 is propelled into the ground without rotating together with the excavating assembly 7.

  When there is a boulder, gravel, and rock mass R in front of the propulsion, these act as resistance to the propulsion of the bit head 6A. When the resistance exceeds the pressing force of the compressed air, the entire bit 6 is axially moved backward until the bit head 6A comes into contact with the lower end of the ring 3B or the lower end of the pipe anchor, which is shortened. This state is shown in FIG. Also at this time, since compressed air is supplied to the hammer portion 7A as described above, as shown in FIG. 18B, the bit 6 again until the flange portion 601 of the housing 6B contacts the end surface of the ring 3B. The forward stroke is shocked, and the bit head 6A collides with the boulders, gravel, and rock mass R.

In this way, when resistance is received by the boulders, gravel, and rock mass R, it retracts as described above and then protrudes with air pressure. During the forward stroke of the bit 6, the pipe anchor 3 is driven and driven integrally with the excavating assembly 7 by the contact between the flange portion 601 of the housing 6B and the ring 3B. The hitting is performed by repeating such an operation, and the rotation of the bit 6 is continued during that time. Therefore, the boulders, gravel, and rock mass R are efficiently crushed in a short time by such rotation and hitting. When the rock 6 has passed through the boulders, gravel, and bedrock R, and the soil has become normal soil, the bit 6 moves forward until the flange portion 601 of the housing 6B comes into contact with the end surface of the ring 3B. Become.
The slime generated in the excavation as described above is discharged to the pipe anchor space on the outer periphery of the hammer portion through the axial groove 603 of the housing 6B, and is sent back through the space on the outer periphery of the rotary shaft portion, from the rear end portion of the pipe anchor. Discharged.

Thereafter, the rotation of the bit 6 through the rotating shaft portion 7B by the drive motor 9 and the striking and propelling motion of the bit 6 by supplying compressed air to the hammer portion 7A are performed, so that the pipe anchor 3 is efficiently and sloped. It is propelled deeply into the ground at a substantially right angle. At this time, the pedestal 9a of the drive motor 9 is guided along the guide rail of the gantry 8, so that the drive motor 9 and each part below it are fed smoothly.
As mentioned above, even if there are boulders, gravel, and bedrock part R in the formation, it will be crushed reliably by the impact of propulsion of the bit head 6A by the rotation of the bit head 6A and the hammer part 7A, so the construction geology is limited. And can be driven quickly and smoothly. Moreover, since the pipe anchor 3 does not rotate, it can be constructed without using water in most grounds other than clay and other than viscosity, and the use of water during excavation can be reduced.

Thus, as shown in FIG. 19A, if the pipe anchor 3 has advanced to a predetermined depth at an angle perpendicular to the slope, the outer diameter of the bit head 6A is equal to the inner diameter of the ring 3B on the inner surface of the tip of the pipe anchor 3. The diameter is reduced to the following. In the illustrated embodiment, the drive motor 9 is rotated in the reverse direction. By doing so, the rotation is transmitted to the bit 6 through the rotating shaft portion 7B and the hammer portion 7A, and the outer diameter of the bit head 6A is reduced.
If the excavating assembly 7 is lifted by operating the winch 100A, the bit head 6A is housed in the pipe anchor 3 as shown in FIG. 19B, and the bit 6, the hammer portion 7A, and the rotating shaft portion 7B are connected to the pipe anchor. 3 is pulled out and only the pipe anchor 3 is left in the ground. As a result, the anchor embedded state shown in FIGS.

Burring of the pipe anchor 3 is completed at the same time as excavation and driving are completed. Since the excavating assembly 7 including the extracted bit head 6A can be repeatedly used by being inserted into the next pipe anchor, it is economical.
Since the pipe anchor 3 does not rotate, the inner and outer surfaces can be plated, and after embedding, there is no worry of corrosion if a cap is applied, so there is no need to dare injecting mortar. Simple and inexpensive.
Further, since the anchor does not rotate, as long as the gantry 8 can be installed, it is possible to embed an anchor in a direction perpendicular to the slope up to a slope of about 60 degrees, and the work can be simplified because the setup of the slope is unnecessary.

If the embedding method of the present invention is used, the pipe anchor is propelled in a non-rotating state by excavation drilling by rotation of the bit head and bit pressing / blowing through the brim brim portion and the thrust receiving portion by the hammer portion, Even if there are boulders, gravel and bedrock, they can be crushed and driven efficiently and smoothly. Moreover, after the required length has been driven, the bit head is reduced in diameter and pulled out through the pipe anchor, so that the pipe anchor is completely embedded, so that the construction can be performed quickly and the bit is not fixed to the pipe anchor and is independent. It is economical because it can be used repeatedly and the pipe anchor can be processed easily.

If the above burying operation is performed for a required intersection ap, the anchor is buried substantially perpendicular to the slope in the 360-degree azimuth. Then, the rope is installed next. The warp and weft may be removed at this point or left as they are.
As for the construction work of the rope, the upper end of each main vertical wire rope 1A is connected to the uppermost anchor by the method shown in FIG. 5A, and the end of each main horizontal wire rope 1B is connected to the left end or right end anchor. Then, the intersection of each of the main vertical wire rope 1A and the main horizontal wire rope 1B is fastened with a coupling fitting 4 as shown in FIGS. 5 (b) and 5 (c), and it is attached to the head of the pipe anchor 3 that has been driven. Join. In addition, about 1 to 5 auxiliary ropes 10A and 10B are stretched between the main vertical wire rope 1A and the main horizontal wire rope 1B, and the intersections are fastened with the coupling bracket 40 as shown in FIGS. To do.
By performing such work, the rockfall prevention facility N as shown in FIGS. 1 to 3 is completed.

In the obtained rock fall prevention facility N, the pipe anchors 3 for fixing the mesh rope can be made uniform in earth pressure on the top, bottom, left and right, and can have equal strength against the pulling force applied to the anchor, especially up, down, left and right. In addition, the fall of the floating stone can be surely and stably suppressed, and the safety can be greatly improved. In addition, since it is not necessary to cut as much as possible the sloped trees, the construction is easier, the environment is less damaged, and the aesthetic appearance is less impaired.

In addition, this invention includes the following rock fall prevention construction methods and rock fall prevention facilities.
1) A plurality of vertical and horizontal wire ropes are laid in a mesh pattern so as to pass over the float stone on the slope where float stones exist, and the ends of the vertical and horizontal wire ropes are fixed by anchors. In the construction method of tightening each crossing part of the rope with a coupling bracket and connecting it to the anchor embedded in the ground along the vertical and horizontal wire ropes and pressing the float stone, the required one of the anchors is the target slope. A rock fall prevention method characterized by burying at a substantially right angle in an orientation of 360 degrees with respect to the part.
2) A plurality of vertical and horizontal wire ropes are laid in a mesh shape so as to pass over the floating stone on the slope where the floating stones exist, and the ends of the vertical and horizontal wire ropes are fixed by anchors, while the vertical and horizontal wires are fixed. In the rockfall prevention facility where the crossing part of the rope is fastened with a coupling bracket and connected to the anchor embedded in the ground, the vertical and horizontal wire ropes are along the surface of the ground and the floating stone is pressed down, the required thing of the anchor is: A rockfall prevention facility characterized by being buried at a substantially right angle in a 360 ° azimuth with respect to the target slope.

It is a perspective view showing an example of a rockfall prevention facility to which the rockfall prevention anchor according to the present invention is applied. FIG. 2 is a partially enlarged view of FIG. 1. FIG. 2 is a partially enlarged perspective view of FIG. 1. It is a front view which shows typically the embedding direction of the anchor in this invention. (a) is a side view showing the connection between the end of the main rope and the terminal fixing anchor (b) is a plan view showing the coupling relationship of the intersection of the main rope and the connection of the anchor, (c) is a side view of the same, ( d) is a plan view showing the intersection of the auxiliary ropes, and (e) is a side view thereof. It is a front view which shows the outline | summary of the embedment apparatus and method of a pipe anchor concerning this invention. (a) is a partial expanded sectional view which shows an example of the pipe anchor and excavation assembly in this invention, (b) is a partial sectional view which shows another example, (c) is a perspective view of (b). It is a perspective view which shows the example of the construction area of this invention. It is a perspective view at the stage where the strip was stretched in a rectangular shape so as to surround the construction range. It is a perspective view which shows the state in the middle of extending the warp. It is a perspective view which shows the state in the middle of extending the weft. It is a perspective view in the state where an intersection for anchor driving was formed. It is a perspective view in the state where a substantially perpendicular angle to the ground surface is determined at the intersection. (a) is the longitudinal cross-sectional view of FIG. 13, (b) is a cross-sectional view. (a) is a side view showing another example of the right angle detection / setting means of the present invention, and (b) is a plan view thereof. (a)-(c) is a side view which shows the right angle detection and setting using the means of FIG. 15 in steps. It is sectional drawing which shows the state of an embedding start stage. (a) (b) is sectional drawing which shows the behavior of a bit when there is a boulder. (a) is a sectional view showing a state where excavation and driving is completed, and (b) is a sectional view showing a state in which a bit is being extracted.

2 Slope 3 Pipe anchor 3B Ring
HTP warp
LTP weft ap
Intersection 15 Tripod-shaped jig 152 Pipe

Claims (3)

In fixing the vertical and horizontal wire ropes stretched in a mesh pattern along the slope surface to the ground,
The vertical and horizontal yarns are stretched along the surface of the planned location at the required intervals, and the intersection of the vertical and horizontal yarns is set as the anchor installation location, and at least two directions at the intersection are measured at right angles to the ground surface. A method for burying rockfall prevention anchors in which a required pipe anchor is driven at a right angle with respect to a surface inclined in the vertical direction with reference to the reference line. In fixing the vertical and horizontal wire ropes stretched in a mesh pattern along the slope surface to the ground,
The vertical and horizontal yarns are stretched along the surface of the planned location at the required intervals, and the intersection of the vertical and horizontal yarns is set as the anchor installation location, and at least two directions at the intersection are measured at right angles to the ground surface. A method for embedding a rockfall prevention anchor, wherein a required pipe anchor is driven in a vertical direction with respect to a surface inclined in the vertical direction and also in the horizontal direction with reference to the reference line. The tripod-shaped jig provided with a guide pipe that penetrates a rod-shaped member at the center is used for measuring at least two directions perpendicular to the ground surface at the intersection. Anchor burying method for rockfall prevention.

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