JP2002054151A - Execution method using cast-in-place grating crib together with lock bolt - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an execution method using a lock bolt together with a cast-in-place grating crib capable of being firmly fixed without causing any dislocation by controlling the entrainment of air when a concrete is sprayed and, at the same time, facilitating the mounting work of a hole form. SOLUTION: A grating crib form 1 is assembled in the shape of a grating at a site, the hole form 6 for forming a lock bolt insertion hole is provided to an intersection of the grating crib form 1, and for the execution method using the lock bolt together with the cast-in-site grating crib driven by spraying the concrete to the inside of the grating crib form 1 of the outside of the hole form 6, the hole form 6 is used for a porous material.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a slope stabilization method, and more particularly, to a method of using a cast-in-place method and a lock bolt. In the present specification, a lock bolt including a ground anchor is referred to.

[0002]

2. Description of the Related Art As one of the slope stabilization methods, a method frame method is used. In this method, a grid-like normal frame is cast on a slope of a ground with concrete (or mortar). When forming this legal form, for example, a reinforcing bar is arranged between a pair of wire mesh frames to form a legal form form, and concrete is blown into the legal form form by air pressure.

On the other hand, rock bolts or ground anchors are sometimes used for stabilizing the slope. In this method, a slope is drilled to embed a lock bolt or an anchor body, and grout is injected and fixed. The lock bolt is fixed in the ground along its entire length, and is fixed to the slope through a washer or a concrete pressure plate without giving a tensile force as it is. The ground anchor is fixed to the slope via the support plate in a state where the tip of the anchor body is fixed and the free length is stretched and tensioned.

When such a lock bolt or a ground anchor (hereinafter simply referred to as a lock bolt) is used together with a legal framer, the lock bolt is buried at the intersection of a grid-like legal frame composed of a vertical frame and a horizontal frame. The head of the lock bolt is fixed to the legal frame using the legal frame as a supporting plate. in this case,
A hole form for forming a lock bolt insertion hole is provided at the intersection of the legal form form in order to secure the lock bolt insertion hole in the law form, and a law form mold outside the hole form form is provided. Concrete is sprayed in the frame. As such a hole frame, a PVC pipe, a void pipe made of paper or the like, a steel pipe, or the like has conventionally been used.

[0005]

However, in the conventional hole form for the lock bolt, when the concrete is sprayed, the air does not escape through the pipe wall of the hole form, so that the air is entrapped in the concrete. It was easy to become a nest state. In order to prevent the occurrence of such nests, timely and careful concrete spraying work was forced, and as a result, the spraying work at the intersections was cumbersome and troublesome.

In addition, since the surface of the conventional perforated formwork is smooth, it is difficult to fix the perforated formwork to the legal formwork when it is installed on site, and the position is determined by the concrete spray pressure. Displacement is likely to occur. In order to prevent such misalignment, it must be fixed firmly with a binding wire or the like, and the fixing operation is troublesome and troublesome, resulting in poor workability.

The present invention has been made in consideration of the above-mentioned prior art, and suppresses the entrainment of air when the concrete is sprayed, and makes it easy to mount the hole formwork and firmly without displacement. An object of the present invention is to provide a construction method which can be used in combination with a fixed-in-place frame and a lock bolt.

[0008]

In order to achieve the above-mentioned object, according to the present invention, a formwork for formwork is assembled in a grid on site, and
A hole form for forming a hole for inserting a lock bolt is provided at the intersection of the legal form form, and concrete is sprayed into the legal form form outside the hole form. In the construction method using both the cast-in-place frame and the lock bolt, the present invention provides a construction method using the cast-in-place frame and the lock bolt in combination, wherein the hole mold is made of a porous material.

According to this structure, since the hole form for the lock bolt is made of a porous material such as a wire mesh, when the concrete or mortar is sprayed on the outside of the hole form, the side surface of the hole form is formed. The air inside the perforated plate forms through the hole (opening) of the perforated plate, and the concrete inside the outside formwork form becomes dense concrete, and a stable concrete form with no nests is obtained. Can be

In addition, since the perforated frame is a perforated plate, the perforated plate can be easily and reliably fixed to the legal frame by passing a binding wire through the hole of the perforated plate. Is improved.

In a preferred configuration example, reinforcing bars are provided on both sides of an upper portion and a lower portion of the inside of the legal form form, and a connecting frame material is bridged between these upper and lower reinforcing bars. It is characterized in that the hole formwork is bound to a material.

According to this configuration, the hole form is firmly fixed and held to the reinforcing bar in the formwork for form via the connection form, and the connection form functions as a reinforcement, and the formwork is formed on the formwork. The formed insertion hole portion for the lock bolt can be reinforced. Further, the present invention provides a hole formwork for forming a lockbolt insertion hole in a cast-in-place method with a lockbolt, which is a hole formwork made of a cylindrical porous material. According to this configuration, when assembling the hole formwork into the legal form formwork at the site, the hole formwork is made of a porous material such as a wire mesh, so that the hole formwork is easily fixed and held at a predetermined position by a binding wire and the like. When concrete or mortar is sprayed into the formwork outside the hole formwork, air escapes through the hole (opening) of the perforated plate constituting the side surface of the hole formwork to the inside of the hole formwork. Therefore, the concrete in the outside formwork form becomes dense concrete, and a stable formwork with no nests and high strength can be obtained.

[0013]

Embodiments of the present invention will be described below with reference to the drawings. 1A and 1B show an embodiment of the present invention, in which FIG. 1A is a top view, and FIGS. 1B and 1C are side views of a hole formwork installation portion in the case of small and large irregularities. In addition, (A) shows the intersection part of the grid-like method frame,
(B) and (C) show only a part of the side surface of the vertical frame continuous along the slope.

As shown in FIG. 1 (A), a formwork 1 according to the present invention comprises a pair of wire mesh frames formed of a net-like form material such as a crimp wire mesh, and a vertical frame 2 and a horizontal frame 3 are arranged in a lattice. A vertical reinforcing bar 4 and a horizontal reinforcing bar 5 are arranged on both sides of each of the wire mesh frames of the vertical frame 2 and the horizontal frame 3 on both sides thereof (a total of four in the vertical and horizontal directions). The pair of metal mesh frames facing each other in the vertical frame 2 and the horizontal frame 3 are connected to each other at predetermined opposing intervals by, for example, a connection spacer (not shown) in a shape of a letter arranged at an appropriate interval. Each rebar 4, 5 is bound to this connecting spacer. Further, stirrups (not shown) for reinforcement may be attached to the vertical and horizontal reinforcing bars 4 and 5 in some cases.

At the intersection of the vertical frame 2 and the horizontal frame 3, there is provided a hole frame 6 for forming an insertion hole for inserting a lock bolt. The hole frame 6 is made of a porous material such as a wire mesh as will be described later.
It is used for steps and fixed to the upper and lower vertical reinforcing bars 4 and horizontal reinforcing bars 5. Concrete is sprayed on the outside of the hole formwork 6 in the formwork 1 for formwork. At this time, the air escapes through the mesh of the hole formwork 6 to the inside of the hole formwork 6, so that the air does not get caught in the concrete frame.

The material and shape of the connection frame member 7 are not limited to the material and shape as long as the hole frame can be firmly fixed to the reinforcing bar. For example, a material in which a wire is bent to provide irregularities or a resin material in which irregularities are reinforced with fibers may be used,
Further, as shown in FIG. 7 described later, wires of the same material as the reinforcing bar may be combined in various shapes.

When the formwork for formwork 1 is set on the slope, if the unevenness is small, the formwork 1 is set on the slope as it is, as shown in FIG. In this case, some gaps (not shown) are formed below the wire mesh frame, but at the time of placing the concrete, the concrete is sprayed while closing with a suitable material. If the unevenness is large, a wire mesh 2a is added below the wire mesh frame of a predetermined shape according to the unevenness as shown in FIG. In this case, as will be described later (FIG. 4), the hole frame 6 is formed by sliding layers having different diameters or by connecting the same diameter with a binding wire or the like, so that the size of the gap between the normal frame and the ground is large. Adjustment is possible to suit.

FIG. 2 is a top view and a side view of the hole formwork according to the present invention. The hole frame 6 through which the lock bolt according to the present invention is inserted is formed of a porous material in order to prevent air from being entrained when spraying concrete or the like. This may be formed into a cylindrical shape as in (A) using a wire mesh (weld wire mesh, crimped wire mesh, turtle wire mesh, etc.) or a conical taper shape as in (B).

Further, as shown in (C) and (D), the steel plate may be formed into a cylindrical shape by using a punching metal or an expanded metal having a large number of round holes or square holes. In addition, a cylindrical shape may be used by using a material that is rigid enough to withstand the spraying pressure and that does not easily generate rust. For example, resin (fiber reinforced plastic (FRP)) is suitable for concrete because its coefficient of linear expansion is close to that of iron. Although the figure shows a cylindrical shape, any shape such as a rectangular shape or other rectangular tube type may be used as long as a predetermined drilling diameter can be secured.

The size of the holes in the steel plate and the mesh (mesh size)
The air is released when the concrete or the like is sprayed, and the sprayed concrete or the like is caught by a wire mesh or the like and slightly enters the inside to form a projection (for example, about 10 × 27 mm). In addition, the mesh may be adjusted by combining metal meshes or perforated steel plates having different meshes. As a result, it is possible to prevent the entrainment of air when spraying concrete or the like, and concrete protrudes into the hole from the mesh of the wall surface of the lock bolt insertion hole, and the concrete and the rock bolt fixing grout material are integrated,
A sufficiently large strength is obtained.

A projecting piece 8 formed by cutting a wire rod of a wire mesh or a steel plate is provided at a lower portion of the hole formwork 6. Formwork for legal form 1
By inserting this protruding piece 8 into the ground when is installed on the slope, it is possible to prevent the position of the lock bolt insertion hole from being shifted due to the blowing pressure of concrete or the like.

FIG. 3 is a schematic view of the cap of the hole formwork.
The cap 9 is attached to the upper part of the hole formwork 6 with a binding wire or the like to prevent concrete or the like from entering the inside of the hole when the concrete or the like is sprayed. As shown in (A), the shape is such that a top is closed and a hook 10 is attached, or (B)
As shown in (1), the top may be closed and the hole 11 may be open. In this case, a wire (not shown) is attached to the hole 11. After the concrete or the like is sprayed, the hook 9 or the wire is pulled to remove the cap 9. As shown in (C), a cap 9 having an open top may be attached to the hole form 6 and the opened portion may be closed with a gum tape or the like (not shown).

In any case, the upper portion of the cap 9 is formed in accordance with the drilling angle in accordance with each site situation. When the drilling angle cannot be obtained, the upper part of the hole form 6 may be closed with a gum tape or the like to prevent the intrusion of concrete or the like.

FIG. 4 is a schematic view when adjusting the length of the hole formwork. As shown in FIG. 1 (C), when the formwork 1 is installed on a slope having a large unevenness, for example, the hole formwork is made longer according to the unevenness, or by unevenness on the slope, or It is necessary to adjust the length (height) of the hole formwork according to the height of the formwork for formwork. In this case, as shown in (A), the hole form frame 6 is connected with a tie wire or the like to adjust the length.
As shown in (B), a hole form having a different diameter (about 10 mm in diameter) is prepared, and the length is adjusted by sliding.
You may connect by a binding wire etc.

FIG. 5 is an assembly view of the formwork for the legal frame. In this embodiment, a mold is assembled first. As shown in (A), the lower reinforcing bar 12 is installed on the slope, and as shown in (B), a pair of wire mesh
6, the vertical frame 2 (horizontal frame 3) is set. Next, as shown in (C), the upper reinforcing bar 13 is placed on the connecting spacer 16, and the upper and lower reinforcing bars 12, 13 and the connecting spacer 16 are fixed to each other with a binding wire or the like. Next, as shown in (D),
At the intersection of the vertical frame 2 and the horizontal frame 3, upper and lower rebars 12, 13 are connected by two-tiered upper and lower connecting frame members (fixing jigs) 7 made of reinforcing bars
Fixed to. The perforated frame 6 is inserted into the upper and lower connecting frame members 7 and fixed with binding wires.

Alternatively, the hole form frame 6 may be provided first, and the connecting frame material 7 may be disassembled and attached so as to be sandwiched from the periphery of the hole form frame 6. Alternatively, the lower connecting frame member 7 is first placed on the lower reinforcing bar, the hole forming frame 6 is disposed through the lower connecting frame member 7, and then the upper connecting frame member 7 is placed on the hole forming frame 6. And finally, the upper and lower connecting frame members 7 and the reinforcing bars and the perforated frames may be fixed with binding wires. At this time, since the perforated frame 6 is a porous material such as a wire mesh, the perforated frame 6 and the connecting frame member 7 can be bound by the binding wire through the mesh, and the binding operation can be easily and reliably performed. As a result, there is no possibility of displacement or the like, and a highly reliable lock bolt insertion hole can be obtained.

FIG. 6 is another assembly view of the legal form frame. In this embodiment, a reinforcing bar is assembled first. (A)
As shown in FIG.
To form a reinforcing bar frame, which is disposed in the vertical and horizontal directions. Next, as shown in FIG. 5B, the grooved frame 6 is attached to the intersections of the vertical and horizontal reinforcing frames by using the connection frame member 7 in the same manner as in FIG. 5D described above. Next, as shown in (C), the wire mesh frame 15 is provided on both sides of the reinforcing bar frame to form the vertical frame 2 (horizontal frame 3).

FIG. 7 is a schematic view of a connection frame member (fixing jig) 7 for fixing the hole frame. As described above, the connecting frame member 7 is used when fixing the die frame 6 to the reinforcing bars 4, 5, 12, and 13. As for the configuration, as shown in FIG. 3A, the hole-shaped frame 6 can be sandwiched with the U-shaped rebar members facing each other.
Alternatively, as shown in (B), as shown in FIG.
Each intersection may be connected to each other by a ring, and may be configured to be foldable. The hole frame 6 is fitted inside with the connecting frame member 7 expanded as shown in the figure.

As shown in FIG. 3C, the connecting frame member 7 may be formed by forming a portion in a shape of a substantially arc along the hole frame 6 so as to sandwich the hole frame 6 with the reinforcing steel members facing each other. Good. Also,
As shown in (D), the reinforcing members may be sequentially attached so as to form a lattice. In this case, the reinforcing members may be previously assembled in a cross-girder shape with the binding wires. By using a reinforcing bar material having the same strength as the reinforcing bar of the formwork as the connecting frame member, it is placed on the reinforcing bar at the intersection of the legal frame and bound, and the concrete loss due to the formation of the lock bolt insertion hole at the intersection point The part can be sufficiently reinforced.

[0030]

As described above, in the present invention, since the hole form for the lock bolt is made of a porous material such as a wire mesh, when the concrete or mortar is sprayed on the outside of the hole form, the hole form is formed. Holes (openings) in the perforated plate constituting the side of the formwork
The air inside the hole formwork passes through, so the concrete in the outside formwork form becomes dense concrete,
It is possible to obtain a law frame with stable strength without nests.

Also, since the perforated frame is a perforated plate, the perforated plate can be easily and reliably fixed to the legal frame by passing a binding wire through the hole of the perforated plate, and workability at the site can be improved. Is improved.

In addition, the hole form is firmly fixed and held to the reinforcing bar in the formwork for the frame through the connection frame material, and the connection formwork functions as a reinforcement, and the lock formed on the lawn is formed. The bolt insertion hole portion can be reinforced.

[Brief description of the drawings]

FIG. 1 shows an embodiment of the present invention, wherein (A) is a top view,
(B) and (C) are side views of a hole formwork installation part in the case of small unevenness and the case of large unevenness, respectively.

FIGS. 2A and 2B are a top view and a side view of a die form according to the present invention.

FIG. 3 is a schematic view of a cap of a hole formwork.

FIG. 4 is a schematic diagram when adjusting the length of the hole formwork.

FIG. 5 is an assembly view of a mold for a legal form.

FIG. 6 is another assembly view of the formwork for the formwork.

FIG. 7 is a schematic view of a connection frame material (fixing jig) for fixing the hole formwork.

[Explanation of symbols]

1: Form frame for legal frame, 2: Vertical frame, 3: Horizontal frame, 4: Vertical reinforcing bar,
5: horizontal reinforcing bar, 6: hole frame, 7: connecting frame material, 8: projecting piece,
9: cap, 10: hook, 11: hole, 12: lower reinforcing bar, 13: upper reinforcing bar, 14: stirrup, 15: wire mesh frame, 16: connecting spacer.

Claims (3)

[Claims] A method for assembling a formwork in a grid pattern on site, providing a formwork for forming a hole for inserting a lock bolt at an intersection of the formwork for formwork. In a construction method using a combination of a cast-in-place method and a rock bolt, in which concrete is sprayed and poured into the outside formwork formwork, wherein the hole formwork is made of a porous material. Construction method with lock bolt. 2. Reinforcing bars are arranged on both sides of the upper and lower portions of the inside of the formwork for formwork, and connecting frame members are bridged between these upper and lower reinforcing bars. The construction method according to claim 1, wherein the hole form frames are bound together. 3. A hole form for forming a lock bolt insertion hole in a cast-in-place frame with a lock bolt, wherein the hole form is made of a cylindrical porous material.