JPH086329B2 - Construction method of slope protection structure - Google Patents

Description

The present invention relates to a method for constructing a slope protection structure.

[Prior art]

A slope protection structure has been developed in which a formwork is assembled on a slope and concrete is placed in the formwork to form a continuous band-like beam. The beams are fixed by anchors placed in the natural ground at positions that are appropriately spaced apart in the longitudinal direction of the beams. There are some beams that are constructed in parallel on the ground, and there are also vertical beams that are almost along the inclination direction and horizontal beams that are orthogonal to them are constructed in a grid pattern. Is.

[Problems to be Solved by the Invention]

In such a slope protection structure, a problem occurs in a beam in a direction orthogonal to the slope direction of the slope, that is, a plurality of parallel horizontal beams or a horizontal beam of a lattice-shaped slope protection structure. That is, the uncured horizontal beam hangs down in the direction of gravity due to the weight of concrete. The part fixed by the anchor does not hang down, but the middle part between them hangs down, so the entire cross beam often wavy.

In order to solve such a problem, it is conceivable to reduce the height of the horizontal beam to reduce the amount of concrete so that the horizontal beam does not hang down. However, a large load acts on the part fixed by the anchor because it attracts the ground. Therefore, if the height of the beam in this portion is reduced, it is not possible to withstand this load.

The present invention has been made to solve the above problems, and provides a construction method for efficiently constructing a slope protection structure capable of preventing the lateral beams from sagging without lowering the overall yield strength. The purpose is to

[Means for solving the problem]

In the method for constructing a slope protection structure of the present invention, two porous weir plates, which are appropriately spaced in the longitudinal direction and have a plurality of elevated heights, are erected in parallel in the lateral direction on the slope. Then, concrete is placed between the barrier plates to form a band-shaped horizontal beam, and the height-increased portion is used as a bearing portion for fixing with an anchor. Also, instead of using a porous weir plate whose height is increased at a plurality of places at appropriate intervals in the longitudinal direction, a strip-shaped porous low weir plate having a constant height is provided at appropriate intervals in the longitudinal direction. A high barrier plate having a height higher than that of the barrier plate may be overlapped with the low barrier plate and used.

The slope protection structure constructed by the construction method of the present invention is a bearing pressure for lowering the height of the intermediate portion between the bearing portions of the lateral beam to reduce the weight, preventing sagging, and fixing to the anchor of the lateral beam. The part is made high in height to obtain sufficient proof stress.

In the slope protection structure in which a plurality of horizontal beams are constructed parallel to the natural ground, pressure bearing portions for fixing to the anchor are formed at appropriate intervals in the longitudinal direction. The height of the intermediate portion between the adjacent bearing portions is lower than the height of the bearing portion.

For slope protection structures where vertical beams and horizontal beams intersect in a grid pattern,
The part where the vertical and horizontal beams intersect is the bearing part, the concrete of the bearing part is high, and the height of the middle part between the lateral beam bearing parts is low. Since there is almost no problem of concrete hanging down the vertical beam, the height of the intermediate portion may be the same as or lower than the height of the bearing portion.

When constructing a lattice-shaped slope protection structure, in addition to the porous weir plate for the horizontal beam of the present invention, a similar porous weir plate for a vertical beam is made parallel to the vertical direction on the slope. A vertical beam may be formed by standing upright and placing concrete between the dam plates. In this lattice-shaped slope protection structure, the intersecting portion serves as a bearing portion fixed to the anchor.

At the intersection of the vertical beam and the horizontal beam, both the horizontal beam and the vertical beam are partially interrupted.

As the porous dam plate, one formed by an extract band metal or a crimp wire net is preferably used.

〔Example〕

The present invention will be described in detail below based on an embodiment shown in the drawings.

FIG. 1 shows an example of a slope protection structure constructed by the construction method of the present invention, in which a plurality of vertical beams 1 extending in a tilt direction and a plurality of horizontal beams in a direction intersecting the tilt direction are shown. Two
Crosses vertically and horizontally to form a grid. Since the vertical beam 1 extends in the direction of inclination, it hardly hangs down due to the weight of concrete, and its height is constant. On the other hand, since the horizontal beam 2 extends in the direction intersecting with the inclination direction, the intermediate portion between the vertical beams 1 and 1 may hang down due to the weight of concrete, and its height is about half that of the vertical beam 1. .

To form such a cross beam 2, a dam plate 3 as shown in FIGS. 6 to 8 is used. FIG. 6 shows one formed by crimp wire mesh, and FIG. 7 shows one formed by extract band metal. In both cases, the heights at a plurality of locations are increased at appropriate intervals in the length direction.

FIG. 8 shows a case in which a low weir plate 3a having a constant height and a low weir plate 3a having a high height are superposed and used as one weir plate. The high barrier plate 3b has a trapezoidal shape, and is attached to the low barrier plate 3a so as to be superposed at a plurality of positions at appropriate intervals in the longitudinal direction. The high barrier plate 3b is easily formed, for example, by obliquely cutting a strip-shaped porous material as shown in FIG.

Further, in order to form the dam plate 3 in which the heights of a plurality of places are increased, one wide strip-shaped material is cut into two dam plates 3 as shown in FIG. Is preferable in terms of material saving.

Two such dam plates 3, 3 are erected vertically parallel to the slope, and the height-increased part intersects with the dam plate for forming the vertical beam 1. At the intersection, both the horizontal beam barrier plates 3 and 3 and the vertical beam barrier plates are partially discontinued.

A plurality of reinforcing bars 4 are arranged between the barrier plates 3, 3. Vertical beam 1
Anchor 5 is placed in the ground at the intersection of the cross beam 2 and the cross beam 2.
A rock bolt or a PC anchor can be used as the anchor 5.

Concrete 6 is placed between the dam plates 3. Raise the concrete 6 on the raised part of the dam plate 3,3,
Increase the height of this part. The crossing portion of the vertical beam 1 and the horizontal beam 2 serves as a bearing portion 7 having a high height. Further, the amount of concrete 6 between the weir plates 3 and 3 having a low height is small, so that the concrete 6 does not sag due to its weight.

The bearing portion 7 is fixed to the anchor 5 described above. A bending moment as shown in FIG. 5 acts on such a horizontal beam 2, and a downward load acts on the bearing portion 7 by the anchor 5 to generate tensile stress on the lower side. In the middle of the space, a force that the ground rises acts, and tensile stress acts on the upper side. The pressure bearing portion 7 has a high height of the concrete 6, and has a tensile strength that is sufficient to withstand this compressive stress. Further, even if the concrete 6 is small in the intermediate portion between the bearing portions 7, 7, the reinforcing bars 4 can withstand the tensile stress.

〔The invention's effect〕

With the construction method of the present invention, horizontal beams having different heights can be easily constructed. In addition, the slope protection structure that is constructed must maintain a good appearance without sagging due to the weight of concrete, because the height of the intermediate part between the bearing parts of the horizontal beam is lower than that of the bearing part. You can In addition, the bearing portion has a sufficient height of concrete, and it is possible to obtain sufficient proof stress capable of withstanding the stress applied by the anchor.

[Brief description of drawings]

FIG. 1 is a perspective view of an embodiment of a slope protection structure constructed by the construction method of the present invention, FIG. 2 is a sectional view thereof, FIG. 3 is a sectional view taken along line III-III of FIG. FIG. 4 is a sectional view taken along the line IV-IV in FIG. 2, FIG. 5 is an explanatory view showing bending moments, and FIGS. 6 to 8 are front views of one embodiment of the dam plate, FIGS. 9 and 10. FIG. 6 is a front view of a member for forming a weir plate. 1 ... Vertical beam, 2 ... Horizontal beam, 3 ... Weir plate, 4 ... Reinforcing bar, 5
…… Anchor, 7 …… Supporting part.

Claims (2)

[Claims] 1. A pair of porous weir plates whose heights at a plurality of locations are appropriately spaced apart in the longitudinal direction are erected vertically parallel to each other in a lateral direction on a slope, and concrete is placed between the weir plates. A construction method of slope protection structure, which is constructed by forming a belt-shaped horizontal beam and using the bearing to fix the height of the beam with anchors. 2. Two strip-like porous low dam plates are erected vertically parallel to each other in the lateral direction on the slope, and are spaced apart in the longitudinal direction of the low dam plate with a height higher than that of the low dam plate. A high barrier plate is piled up on a low barrier plate and erected in parallel vertically, and concrete is placed between the barrier plates to form a horizontal cross beam, and the height-enhanced part is fixed by an anchor. Construction method of slope protection structure used as bearing part.