JPH0967823A - Slope stabilizing method and anchor fixing pedestal used therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To greatly reduce the weight when anchor fixing pedestals are conveyed and installed, advance speedily and easily work and to make it possible to stably hold the slope irrespective of unevennesses. SOLUTION: A plurality of ground anchors 4 are driven to a slope 3 cut off a bedrock, and anchor fixing pedestals 1 are installed to ground surface exposed sections of the ground anchors 4 while holding bag bodies 8 between the bottoms of the pedestals and subsoil and are temporarily fixed to tension members 6. After the neighboring anchor fixing pedestals 1 are connected to each other, the insides of them are filled with mortar from filler pouring holes. Mortar is pumped into also the bag bodies 8 and is expanded to fill up voids between the anchor fixing pedestals and subsoil 3a. After the filling of mortar to the bag bodies 8 is stopped to seal up and solidify the bag bodies 8, the anchor fixing pedestals 1 are completely anchored to the tension members 6 to complete the ground anchors 4, and the stabilized slope 3 is constructed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a slope stabilizing method for stably constructing a slope in a slope cutting work and the like, and an anchor fixing pedestal used therefor.

[0002]

2. Description of the Related Art Conventionally, as a method for stabilizing steep slopes that are cut out from the ground or slopes that are prone to landslides, a ground anchoring section of a ground anchor has been conventionally installed on the slope, and the ground anchor is exposed to the surface. There was a construction method to stabilize a slope by fixing a precast concrete block (hereinafter abbreviated as PC block) as a pedestal for anchoring to the section and performing the same work sequentially from the upper stage to the lower stage of the slope. No. 52812). However, since the weight of the PC block is large in this conventional construction method, the PC block is installed on the slope using a large heavy machine such as a crane.
Furthermore, it is necessary to support these with a crane or the like until the fixing is completed, and the work is troublesome and takes time. Further, the work is extremely difficult in a place where the PC block cannot be carried in by a crane such as a high place where the crane cannot reach. In addition, if the ground has large irregularities, the contact between the PC block and the ground will be uneven, and the bearing pressure that supports the ground as a ground anchor will be transmitted in the form of concentrated load only at the contact part, thus stabilizing the ground. It is low, the slope may be loosened, and stress may be concentrated on the PC block, leading to damage.

[0003]

SUMMARY OF THE INVENTION The problem to be solved by the present invention is to solve the above-mentioned problems and to greatly reduce the weight of the anchor fixing pedestal at the time of carrying in / installing, thereby making the work quick and easy. It is an object of the present invention to provide a slope stabilization method and an anchor fixing pedestal used therefor that can be advanced and can stably hold a slope regardless of the unevenness of the ground.

[0004]

[Means for Solving the Problems] The structure of the present invention which has solved the above problems is as follows: 1) Ground anchors are driven at predetermined vertical and horizontal intervals on a slope from which ground is cut, and a tension member for the ground anchor is provided at the center. A hollow anchor fixing pedestal having a through hole and a filling material injection hole is installed on each ground anchor ground surface portion of the slope, and the installed anchor fixing pedestals are connected to each other, and the respective filling materials are provided. After filling the filling material that hardens into the anchor fixing pedestal from the injection hole,
A slope stabilization method that completely fixes the anchor anchoring pedestal and the ground anchor tension member to hold the slope stably 2) The ground anchoring part of the ground anchor is formed into an inflatable and retractable bag inside An inflatable anchor having a structure for fixing the ground and the underground fixing part by expanding the diameter of the underground fixing part by press-fitting cement milk, and the vertical and horizontal dimensions of the anchor fixing pedestal are the vertical and horizontal dimensions of the ground anchor arrangement. The slope stabilization method described in 1) above, wherein the distance is substantially equal to the predetermined interval. 3) The anchor fixing pedestal is installed while sandwiching the bag between the anchor fixing pedestal and the slope ground, and the anchor fixing pedestals are connected to each other, and then cured in the anchor fixing pedestal and in the bag body. Fill the filling material to
The slope according to 1) or 2) above, wherein the bag body is inflated to fill a space between the anchor fixing base and the ground, and the anchor fixing base and the tension member are completely fixed after the filling material in the bag body is cured. Stabilization method 4) A hollow box-shaped structure with a hole through which the tensile member of the ground anchor penetrates at the center and a filler injection hole for filling the inside with filler at the end. Characteristic pedestal for anchor anchoring 5) An anchor anchoring according to 4), wherein the planar shape is a cross shape, and a filler injection hole and a connecting metal fitting for connection are provided at each end of the cross-shaped extending portion. For pedestal 6) By inserting square pipes into the pedestal base from four directions so that it can expand and contract, a cruciform centered on the pedestal base is constructed.
The anchor fixing pedestal according to the above 5), wherein the inserted rectangular pipe is connected to the base of the pedestal in a cross-shaped manner so that the vertical and horizontal dimensions can be adjusted.

[0005]

BEST MODE FOR CARRYING OUT THE INVENTION In the slope stabilization method of the present invention, first, a plurality of ground anchoring portions of ground anchors are formed at predetermined intervals in the vertical and horizontal directions on a slope formed by cutting out the ground to form a ground. The tension member of the anchor is exposed on the ground surface. Next, a hollow anchor fixing pedestal provided with a hole for penetrating the tension member in the central portion and provided with a filler injection hole, on the ground surface portion of each ground anchor on the slope,
The tension member is installed in a penetrating state and temporarily fixed. As the anchor fixing base, a combination of steel materials having sufficient strength is mainly used. As the steel material, it is desirable to use a weather resistant steel material that is particularly resistant to corrosion. The anchor fixing pedestals temporarily fixed at the predetermined intervals are connected to the adjacent anchor fixing pedestals, and then the filler is injected from the filler injection holes. As the filler, mortar, concrete, or the like having a hardening property is used. Once the anchor fixing pedestal has been sufficiently filled with the filling material, the anchor fixing pedestal and the tension member that has passed through the hole are completely fixed while giving a predetermined tension force, and the ground anchor is used as the ground fixing section. Finalize. By connecting ground anchors having heavy anchor anchorage pedestals to each other at the anchor anchorage pedestals, the ground can be uniformly supported over a wide range and the slope can be stably held.

In the method of using the expansion type anchor and making the vertical and horizontal dimensions of the anchor fixing pedestal almost equal to the vertical and horizontal predetermined intervals of the ground anchor arrangement, first, the vertical and horizontal directions are respectively set on the ground of a slope made by cutting the ground. A plurality of ground anchors are installed at intervals, and the tension members of the ground anchors are exposed on the ground surface. Next, cement milk is pressed into the underground fixing portion to expand the diameter of the underground fixing portion, thereby fixing and fixing the underground fixing portion to the ground. After that, if the anchor anchoring pedestals are installed on the ground surface portions of the ground anchors on the slope, the anchor anchoring pedestals are vertically and horizontally adjacent to each other.
The adjacent portions may be connected to each other.

According to the method of sandwiching the bag between the anchor fixing pedestal and the slope, when the anchor fixing pedestal is installed on the ground surface of each ground anchor on the slope, the bag is separated from the anchor fixing pedestal and the slope ground. Sandwich it in between. In the bag,
Use a material that has both flexibility and toughness, such as a woven cloth bag made of aramid fiber that has high strength that does not break even if a high pressure is applied from the inside or outside. . After the anchor fixing pedestals are temporarily fixed, the anchor fixing pedestals are connected to each other, and the filler is injected through the filler injection holes. At the same time, the bag is filled with the same filling material. The bag expands due to the filling material, fills the space between the anchor fixing base and the ground caused by the unevenness of the ground, and is in a state of strongly adhering to the bottom surface of the base and the ground surface. When the inside of the bag reaches a predetermined pressure, the filling is stopped and the bag is sealed while maintaining the pressure. The filling material inside the bag is cured while maintaining the pressure while the filling material is sufficiently filled inside the anchor fixing pedestal. When the inside of the bag is completely hardened, the anchor fixing base and the tension member are completely fixed while giving a predetermined tension force to complete the ground anchor. The bearing pressure is evenly distributed and transmitted from the anchor fixing pedestal to the ground through the bag, and the ground can be reliably supported and the slope can be held more stably.

[0008]

An embodiment of the present invention will be described with reference to the drawings.
This embodiment is an example in which an inflatable anchor is used and a bag is sandwiched between an anchor fixing pedestal and a slope ground to inflate. FIG. 1 is an explanatory diagram showing a ground anchor setting state of a ground anchor in the embodiment, FIG. 2 is an explanatory diagram showing an anchor fixing base installation state of the embodiment, and FIG. 3 is a mortar filling operation of the embodiment. Explanatory drawing, FIG. 4 is an explanatory view showing a slope after completion of construction of the embodiment, FIG. 5 is a plan view of an anchor fixing base used in the embodiment, and FIG. 6 is a front view of an anchor fixing base used in the embodiment. 7 is a sectional view taken along the line AA of FIG. 6, FIG. 8 is a plan view showing another example of the anchor fixing base used in the embodiment, and FIG. 9 is a front view showing another example of the anchor fixing base used in the embodiment. 10 is a sectional view taken along line BB in FIG.

Anchor fixing base 1 used in this embodiment
Has a cross shape in a plan view and has the same vertical and horizontal dimensions of 2.9 m,
And it is a hollow box made of steel with a height of about 30 cm. An anchor hole 1a for penetrating the tension member 6 of the ground anchor 4 is provided in the center of the cross shape, and a filler injection hole 1b and a bolt 11 fastening type coupling fitting 1c, 1d are provided at each tip of the cross-shaped extending portion. Each is provided. The inside is reinforced by a partition plate 1e having holes.
This anchor fixing pedestal 1 is made of a weather resistant steel material (for example, Corten manufactured by Nippon Steel Corporation) so that corrosion does not easily occur on the slope 3.

As another example of the anchor fixing pedestal 1 used in this embodiment, an example in which a cross-shaped structure having adjustable vertical and horizontal dimensions is shown (see FIGS. 8, 9 and 10). This anchor fixing pedestal 1 has a mechanism in which a square pipe 16 can be inserted into and removed from four sides in a pedestal base portion 15 having an anchor hole 1a through which a tensile member 6 of a ground anchor 4 penetrates in a central portion, and a dimension can be adjusted. After adjustment, the pedestal base 15 and the square pipe 16 are fixed and connected by the pin 17. Inside the pedestal base 15, there is provided a partition plate 18 with a hole that serves as a stopper for the rectangular pipe 16 as well as reinforcement. At the tip of each square pipe 16, a filler injection hole 1b and a bolt-type connecting fitting 1 are provided.
c and 1d are provided respectively.

In the construction by the slope stabilization method of this embodiment, first, a plurality of expansion anchors are formed on the ground 3a of the slope 3 which is cut by a predetermined height from above the planned cutting portion of the ground 2. The underground fixing portions 5 of the ground anchors 4 are placed at intervals of about 3 m in length and width (see FIG. 1). After placing, the adjustment block 7 is attached to the exposed surface of each ground anchor 4, and the anchor fixing pedestal 1 is sandwiched with the bag body 8 made of aramid fiber woven cloth between the bottom surface and the ground 3a. However, the cross should be installed so that it points vertically and horizontally (see Figure 2). The anchor fixing base 1 is temporarily fixed to the tension member 6 penetrating the anchor hole 1a so as not to move on the slope 3. Attach the anchor fixing pedestals 1 that are adjacent to each other vertically and horizontally, and attach the connecting metal fittings 1c and 1d to the bolts 1.
The slanted surface 3 is supported in an integrated state by being engaged by engaging with each other. After that, the mortar 12 is injected from the filler injection hole 1b of each anchor fixing pedestal 1 by the injection device 13 and is filled inside to increase the weight of the anchor fixing pedestal 1. Similarly, the mortar 12 is pressed into the bag 8 between the bottom surface of the anchor fixing base 1 and the ground 3a by the press-fitting device 14 to inflate the bag 8. Inflated bag 8
Fills the space between the bottom surface of the anchor fixing pedestal 1 and the ground 3a without any gap, and the upper and lower surfaces of the bag body 8 are in close contact with the bottom surface of the anchor fixing pedestal 1 and the surface of the ground 3a, respectively (FIG. 3).
reference). After that, when the inside of the bag body 8 reaches a predetermined pressure, the filling by the press-fitting device 14 is stopped, and the bag body 8 is sealed while the pressure inside the bag body 8 is maintained, and the bag body 8 is cured as it is. When the mortar 12 in the bag 8 is completely hardened, the anchor fixing base 1
Is completely fixed while applying a predetermined tension force to the tension member 6 through the fixing tool 9, the cap 10 is attached, and the ground fixing portion 4a of the ground anchor 4 is formed to complete the ground anchor 4. By hardening the mortar 12 in the anchor fixing pedestal 1, the ground fixing portion 4a of the ground anchor 4 is strong and has both weight and strength. The weight of the anchor fixing pedestal 1 and the bearing pressure of the ground anchor 4 are evenly transmitted from the bottom surface of the anchor fixing pedestal 1 to the ground 3a via the bag body 8, so that the slope 3
Can be strongly and stably held.

When each ground anchor 4 is fixed and completed and a stable slope 3 can be constructed, the lower stage next to the part to be cut off of the natural ground 2 is cut off, and the second slope 3 is constructed in the same manner as above, By repeating this, the slope 3 that is stable up to the bottom can be constructed.

The anchor fixing base 1 is provided with a slope 3
It can be installed and fixed with weather resistance and corrosion resistance enhanced by painting with a color tone that suits the environment. Slope 3
After the above construction, the joined anchor fixing bases 1 may be collectively coated.

[0014]

According to the present invention, by adopting the above-described method, the anchor fixing base can be moved in a lightweight state at the time of carrying in and installing, and the carrying in / installing at the work site without using a large heavy machine such as a crane. Can be performed easily and smoothly, the burden on the operator can be reduced, and the working time can be shortened. In addition, workability in places where it was difficult to work, such as in high places, is greatly improved, stable slopes can be constructed over a wide range, and ground protection can be reliably performed.

When the method of using the expansion type anchor as the ground anchor is adopted, the underground fixing portion is fixed to the ground by expansion, so that it is not necessary to wait for the injection grout to be the underground fixing portion to be hardened, which is required in the conventional construction. The period can be shortened.

By adopting a method of sandwiching the bag between the anchor fixing base and the sloped ground, even if the ground has irregularities, the bearing pressure is even from the bottom surface of the anchor fixing base through the expanded bag. In addition to the ground, the ground can be stably supported, and the reliability of slope maintenance is greatly improved.

[Brief description of drawings]

FIG. 1 is an explanatory diagram showing a ground anchor setting state of a ground anchor in an embodiment.

FIG. 2 is an explanatory view showing an anchor fixing pedestal installation state of the embodiment.

FIG. 3 is an explanatory view showing a mortar filling operation of the embodiment.

FIG. 4 is an explanatory view showing a slope after completion of construction in the embodiment.

FIG. 5 is a plan view of an anchor fixing base used in the embodiment.

FIG. 6 is a front view of a base for anchor fixing used in an example.

7 is a cross-sectional view taken along the line AA of FIG.

FIG. 8 is a plan view showing another example of the anchor fixing pedestal used in the embodiment.

FIG. 9 is a front view showing another example of the anchor fixing pedestal used in the embodiment.

10 is a sectional view taken along line BB of FIG.

[Explanation of symbols]

 1 Anchor fixing pedestal 1a Anchor hole 1b Filler injection hole 1c Connecting metal fitting 1d Connecting metal fitting 1e Partition plate 2 Ground 2a Cutting step 3 Slope 3a Ground 4 Ground anchor 4a Ground fixing part 5 Underground fixing part 6 Tensile member 7 Adjustment block 8 Bag 9 Fixing Tool 10 Cap 10a Waterproof Filler 11 Bolt 12 Mortar 13 Injection Device 13a Injection Pipe 14 Press-fitting Device 14a Press-in Pipe 15 Pedestal Base 16 Square Pipe 17 Pin 18 Partition Plate

Claims (6)

[Claims] 1. A hollow anchor in which ground anchors are driven at predetermined vertical and horizontal intervals on a slope from which the ground is cut, and a hole through which a tensile member of the ground anchor penetrates is provided and a filler injection hole is provided. After mounting the fixing pedestal on each ground anchor ground surface part of the slope, connecting the installed anchor fixing pedestals to each other, and filling the curing agent into the anchor fixing pedestal through the respective filler injection holes. , A slope stabilization method that completely fixes the anchor anchoring base and the tension member of the ground anchor to hold the slope stably. 2. The ground anchoring portion of the ground anchor is formed into a bag shape that can be expanded and contracted, and cement milk is press-fitted therein to expand the diameter of the underground anchoring portion, thereby fixing the ground and the underground anchoring portion. The slope stabilizing method according to claim 1, wherein the structure is an expansion type anchor and the vertical and horizontal dimensions of the anchor fixing pedestal are substantially equal to predetermined vertical and horizontal intervals of the ground anchor arrangement. 3. The anchor fixing pedestal is installed while sandwiching the bag between the anchor fixing pedestal and the sloped ground, and the anchor fixing pedestals are connected to each other, and then inside the anchor fixing pedestal and the bag. Filling the body with a hardening filler, inflating the bag to fill the gap between the anchor fixing pedestal and the ground, and completely fixing the anchor fixing pedestal and the tension member after the hardening of the filling material in the bag. The slope stabilization method according to claim 1 or 2. 4. A hollow box-shaped structure, wherein a hole through which a tensile member of a ground anchor penetrates is provided in a central portion thereof, and a filler injection hole for filling a filler into the inside is provided at an end portion. A pedestal for anchor anchoring. 5. The anchor fixing pedestal according to claim 4, wherein the planar shape is a cross shape, and a filler injection hole and a connecting metal fitting for connection are provided at each end of the cross-shaped extending portion. 6. A cruciform centered on the pedestal base is formed by inserting the rectangular pipes into the pedestal base from four directions so that the dimensional crosswise shape of the inserted rectangular pipe can be adjusted on the pedestal base. The anchor fixing base according to claim 5, which is connected.