JP2655137B2 - Slope construction method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a slope construction method for firmly holding a slope such as a slope or a vertical surface based on a ground anchor construction method used in civil engineering works.

[0002]

2. Description of the Related Art In order to stably hold the ground on a slope such as a slope or a vertical surface, conventionally, a large number of ground anchors are provided at predetermined intervals on the slope and beams are provided between the anchors. The slope construction method of connecting each anchor has been performed. According to this method, the stability of the ground was improved by holding the ground with each of the integrated anchors. However, when placing a formwork with a bottom plate between the anchors when placing the beams connecting the anchors, even if the completed beam and the ground surface are in contact with each other, due to the unevenness of the ground surface and the presence of stones Non-uniform partial contact occurred, and the pressing force of the beam to the ground due to the tension of the anchor was transmitted only by concentrated load, and did not act as an effective prestress from the beam to the ground. When the formwork was directly driven into the ground without providing a bottom plate, the completed beam and the ground surface were completely adhered to each other, but the prestress did not act because only the weight of the beam was added to the ground. For this reason, the prestress by the anchor is unlikely to work on the ground other than around the anchor, and there is a possibility that the slope may collapse due to instability. In order to prevent instability, it is necessary to increase the installation density of anchors, but there is a limit to narrowing the spacing,
It was difficult to obtain sufficient slope strength.

[0003]

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems, to uniformly generate prestress over a wide area of the ground surface, and to keep the ground strong and stable. It is to provide a surface construction method.

[0004]

Means for Solving the Problems The constitution of the present invention which has solved the above problems is as follows: 1) A plurality of ground anchors are provided at predetermined intervals on a slope, and a ground anchor is provided between the ground anchors of these ground anchors. While installing the concrete beam formwork to be connected, laying a bag approximately the same size as the beam bottom between the formwork and the ground, concrete was poured into the formwork and integrated with each ground anchor After forming the beam and removing the formwork, a hardening filler such as mortar is press-fitted into the bag to expand it, and the gap between the beam and the ground is completely filled with the bag and pressure is applied. Slope construction method in which the filler is hardened by holding in a manner and prestress is applied to the ground below the bag. 2) A plurality of ground anchors are provided at predetermined intervals on the slope and A concrete beam formwork that connects the ground anchors between the ground anchorage sections is installed, and between the formwork and the ground, it absorbs water of almost the same size as the beam bottom and expands to maintain the expanded shape. After laying the sheet provided, concrete is poured into the formwork to form a beam integrated with each ground anchor, and after removing the formwork, the sheet is allowed to absorb water and expanded, and the beam and the ground are removed. The slope between the ground anchors is filled with a sheet without gaps and completely expanded to maintain a high pressure so that prestress is applied to the ground below from the sheet. Reinforcing bars were arranged in the formwork between them, and after connecting the reinforcing bars to the ground anchorage of the ground anchor, concrete was poured into the formwork to form beams integrated with each ground anchor. 1) Written in 4) Reinforcing bars are arranged in the formwork between the ground anchors, and the rebars are connected to the ground anchoring portion of the ground anchor, and then concrete is poured into the formwork to form the ground anchors. The slope construction method according to 2), wherein an integrated beam is formed.

[0005] In the method of the present invention, the bag for press-fitting the hardening filler used between the beam and the ground surface has a strength that does not break even when high pressure is applied in contact with an uneven surface such as aramid fiber. A woven cloth bag or a rubber bag made of a material is mainly used. Hardening materials such as mortar, grout, concrete and the like are mainly used for filling the bag. Further, the sheet used in the same manner as described above and having the property of expanding by absorbing water and maintaining the shape after expansion, irreversibly expands 3 to 4 times by absorbing water and withstands a pressure up to about 1.5 kgf / cm ^2. A material obtained by mixing a rubber and a polymer material such as sodium polyacrylate that maintains its shape and processing it into a flexible sheet shape is used.

[0006]

According to the slope construction method of the present invention, a plurality of ground anchors are first placed at predetermined intervals on the slope. Next, a bag of approximately the same size as the bottom of the concrete beam to be installed between the ground anchors of each ground anchor is laid on the ground surface directly below the beam, and a beam formwork is placed thereon.
Concrete is poured into a mold and hardened, a beam is formed, and the mold is removed. After that, a hardening filler such as mortar is press-fitted into a bag below the beam using a press-fitting device. The bag inflated with the filling fills the gap between the bottom of the beam and the surface of the ground, and the upper and lower surfaces adhere to both surfaces. When the pressure in the bag reaches a predetermined amount, press-fitting of the filling is stopped while maintaining the pressure, and the bag is sealed. At the same time, the same operation is performed on the other beams, and when the filling hardens, the ground below the beams can be prestressed from the bag supported on the upper side by the beams.

[0007] In the construction method of providing a sheet having the property of absorbing water and expanding and maintaining the shape after expansion between the beam and the ground surface, ground anchors are provided at predetermined intervals on the slope, as in the case of the bag described above. Cast in. Next, a sheet having substantially the same size as the bottom surface of the concrete beam installed between the ground anchoring portions of the ground anchors is laid on the ground surface directly below the beam, and a beam form is installed thereon. After casting concrete in the formwork and hardening, forming a beam and removing the formwork, give enough moisture to the sheet under the beam, the sheet will absorb water and expand, and it will spread to the bottom of the beam and the ground surface The upper and lower surfaces of the sheet are brought into close contact with both sides, respectively, to fill the gap thus formed. If the expansion of the sheet due to the water absorption is completely stopped, the sheet shape is maintained with the pressure increased between the beam and the ground surface. Thus, prestress can also be applied to the ground below the beam from the sheet whose upper side is supported by the beam.

In the construction method in which the ground anchoring portions of the ground anchors are connected to each other by a reinforcing bar to form a concrete beam, a bag or sheet having substantially the same size as the bottom of the concrete beam is laid between the ground anchors at predetermined intervals. In addition to installing the beam formwork on this, both ends of the reinforcing bars arranged in the formwork are attached to the ground anchoring sections, respectively, and the ground anchor is connected by the reinforcing bars. Once the formwork surrounding the rebar has been created, cast concrete into the formwork and cure it.
Form a beam. Thereafter, the operation of expanding the bag or sheet may be performed.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments 1 and 2 of the present invention will be described with reference to the drawings. Example 1 is an example of a construction method in which a beam containing a reinforcing bar is installed between ground anchors, and mortar is pressed into a bag previously laid under the beam to expand the mortar, and Example 2 absorbs the bag of Example 1 by absorbing water. This is an example in which the sheet is replaced with an expanding sheet. FIG. 1 is an explanatory diagram showing a concrete beam placing process of the first embodiment, FIG. 2 is an explanatory diagram showing a bag expanding process of the first embodiment, and FIG.
Is a cross-sectional view showing a main part of the ground anchor of Example 1.
FIG. 4 is a cross-sectional view showing an inflated state of the bag according to the first embodiment, FIG. 5 is an explanatory view showing an installed state of the beam formwork of the first embodiment, and FIG. 6 is an explanatory view showing an installed state of the beam and the bag of the first embodiment. FIG. 7 and FIG. 7 are explanatory views showing the sheet expanding process of the second embodiment. In the slope construction method of the first embodiment, first, the tension member 3 of the ground anchor 1 is used.
By placing an anchor body 2 in the ground
It is fixed to the ground 17 constituting the slope. Similarly, the plurality of tension members 3 are arranged on the slope at a pitch of about 2 m and fixed to the ground 17. A pedestal 4 provided with a plurality of reinforcing bars 5 for connecting the reinforcing bars 8 of concrete beams is installed on the exposed surface of each of the tension members 3. The fixing device 7 and the support plate 6 are placed on the pedestal 4, and the fixing device 7 is fixed to the tension member 3 to form a ground anchor 1 serving as a ground fixing portion. Let it work. next,
An aramid fiber bag 13 having substantially the same size as the bottom surface of a 30 cm square concrete beam 10 to be provided between the ground anchors 1 is placed on the surface of the ground 17 at a position corresponding to the position below the beam 10. Then, both ends of the reinforcing bar 8 are welded to the connecting reinforcing bar 8 of the pedestal 4, and the ground anchors 1 are connected by the reinforcing bar 8, and at the same time, the form 9 for the beam 10 is installed between the ground anchors 1. After the concrete 11 is cast into the form 9 and hardened to form the beam 10, the form 9 is removed, and the mortar 14 is pressed into the bag 13 below the beam 10 by the press-fitting device 12. When the mortar 14 is pressed into the bag 13, the bag 13 expands and fills the gap formed between the bottom surface of the beam 10 and the surface of the ground 17. The pressure in the bag 13 increases from the bag 13 to the ground 17.
When a pressure sufficient to give sufficient prestress is reached, press-fitting of the mortar 14 is stopped while maintaining this pressure, and the bag 13 is sealed and cured. After the mortar 14 is hardened, a uniform pre-stress can be applied to the ground 17 on the lower surface from the bag 13 supported on the upper side by the beams 10 firmly held by the ground anchors 1 at both ends, and the ground 17 is strongly held. .

[0010] In the slope construction method of the second embodiment, the bag 13 of the first embodiment irreversibly expands about 3 to 4 times when absorbing water, and retains its shape after the change is completed. (Ex. Nice Seal (trademark) made by a company). After a plurality of ground anchors 1 are provided on the slope, 30c is provided between the ground anchors 1 having a pitch of about 2 m.
A bag 1 having approximately the same size as the bottom of the m-square concrete beam 10
The sheet 15 that is used in place of the sheet 3 is placed. As in the first embodiment, the reinforcing bar 8 and the formwork 9 are provided, concrete 11 is cast and hardened to form the beam 10, and then the formwork 9 is removed. After this, a sufficient amount of water 1 to fully expand the sheet 15
6, the sheet 15 expands due to water absorption and the beam 10
The gap formed between the bottom surface and the surface of the ground 17 is filled, and the upper and lower surfaces of the sheet 15 are in close contact with both surfaces, so that a uniform pressure is applied from the sheet 15. When the expansion is completed, the sheet 15
Is fixed, the sheet 15 supported on the upper side by the beam 10 firmly held by the ground anchors 1 at both ends.
Thus, an even prestress can be applied to the ground 17 on the lower surface, and the ground 17 is strongly held.

[0011]

According to the present invention, by adopting the above-described structure, each ground anchor and the bag or sheet under the beam provided between the ground anchors are in close contact with a larger portion of the ground surface, Prestress can be given evenly,
Keeping the ground strong and stable minimizes the risk of instability in the slope.

[Brief description of the drawings]

FIG. 1 is an explanatory view showing a concrete beam placing process of Example 1.

FIG. 2 is an explanatory view showing an inflation step of the bag according to the first embodiment.

FIG. 3 is a cross-sectional view illustrating a main part of the ground anchor according to the first embodiment.

FIG. 4 is a sectional view showing an inflated state of the bag according to the first embodiment.

FIG. 5 is an explanatory view showing a state in which a beam formwork is installed in the first embodiment.

FIG. 6 is an explanatory diagram showing an installation state of a beam and a bag according to the first embodiment.

FIG. 7 is an explanatory view showing a sheet expanding process of Example 2.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Ground anchor 2 Anchor body 3 Tensile member 4 Pedestal 5 Reinforcing bar 6 Support plate 7 Fixing tool 8 Reinforcing bar 9 Formwork 10 Beam 11 Concrete 12 Press-in device 13 Bag 14 Mortar 15 Sheet 16 Water 17 Ground

Claims (4)

(57) [Claims] 1. A plurality of ground anchors are provided on a slope at predetermined intervals, and a concrete beam formwork for connecting the ground anchors is installed between the ground anchoring portions of the ground anchors, and the formwork and the ground are fixed. After laying a bag of approximately the same size as the bottom of the beam in between, cast concrete into the form to form a beam integrated with each ground anchor, remove the form, and then in the bag The filling material such as mortar or the like that is to be hardened is press-fitted and expanded, and the gap between the beam and the ground is filled with a bag without any gap. Slope construction method to add stress. 2. A plurality of ground anchors are provided at predetermined intervals on a slope, and a concrete beam formwork for connecting the ground anchors is installed between the ground anchoring portions of the ground anchors. A sheet integrated with each ground anchor by laying a sheet having the property of absorbing water of approximately the same size as the bottom of the beam and expanding to maintain the expanded shape, and then placing concrete in the formwork After removing the formwork, the sheet is expanded by absorbing water, filling the gap between the beam and the ground without a gap, completely expanding and maintaining a state where the pressure is increased,
A slope construction method in which prestress is applied to the ground below the sheet. 3. A reinforcing bar is arranged in a formwork between the ground anchors, and the reinforcing bar is connected to a ground anchoring portion of the ground anchor, and then concrete is poured into the formwork to be integrated with each ground anchor. 2. A shaped beam is formed.
Slope construction method described in. 4. A reinforcing bar is arranged in a formwork between the ground anchors, and the reinforcing bar is connected to a ground anchoring portion of the ground anchor, and then concrete is cast into the formwork to be integrated with each ground anchor. 3. A shaped beam is formed.
Slope construction method described in.