JPH01190821A - Anchor method - Google Patents

Abstract

PURPOSE:To improve anchoring force by inserting a tension member in a belt form having specified thickness and width into an excavated hole provided for a bed rock, anchoring the tension member at its tip end with a curing agent, and thereby straining the tension member thereafter so as to be anchored at the surface of the bed rock. CONSTITUTION:Separation from a bed rock 2 is made by a sheath except the tip end of a tension member 1. Then, the tension member 1 composed of a steel plate the thickness and width of which are equal to or more than 0.6-20mm and 50mm respectively, is inserted into a flat excavated hole 5. And then, a curing agent 6 such as mortar and the like are filed into the tip section of the excavated hole 5 so as to be cured. Following which, the tension member 1 is furthermore strained by means of a hydraulic jack and the like. In addition, a wedge 8 is driven into a pedestal 7 over a protective wall 3 so as to be anchored.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to an anchor construction method using a band-shaped tensile material.

[Conventional technology]

This type of anchor construction method is widely used for earth retaining and prevention of structures from floating up. Furthermore, there are fixation (permanent), removal (temporary), and repressurization (permanent) methods, and the tensile material used is a PC steel rod or a PC steel stranded wire.

[Problem to be solved by the invention]

However, the tensile material in conventional construction methods relies on the adhesive force between the steel rod or steel strand and the hardened material, but the contact area is small and sufficient adhesive force cannot be obtained.

Therefore, in order to increase the adhesion force, the fixing length must be increased, which increases the length of the tensile material and the amount of hardening material used, which is uneconomical. Furthermore, since the strength of each anchor is not sufficient, a large number of anchors must be provided, which increases construction costs. Furthermore, in the case of diagonal insertion to stabilize a slope, the area subject to earth pressure is small, and the resistance to earth pressure is small, making it insufficient to prevent landslides and the like.

Therefore, the main object of the present invention is to provide an anchor construction method in which the contact area between the tensile material and the hardening material is large, the anchorage force and proof stress during tension are increased, and the anchorage part is firmly anchored to the ground. be.

[Means to solve the problem]

In order to solve the above problems, the present invention forms a flat hole and has a thickness of 0.6 to 20 m in the hole.
A band-shaped tensile material with a width of 59 mm or more is inserted, and the tip of this tensile material is fixed to the ground by a hardening material filled with it, and after the hardening material is hardened, the tensioning material is tightened and fixed to the surface of the ground. It is characterized by this.

[For production]

In the present invention, since a strip material is used as the tensile material,
Based on a comparison per unit cross-sectional area, the contact area with the hardened material is larger than when using steel rods or steel stranded wires, and sufficient adhesive force can be obtained with a short anchorage length, reducing the amount of hardened material used. The cost of materials used is lower because ropes can be used more easily and are cheaper per the same cross-sectional area.

A large contact area means that the resistance force under tension becomes large, and sufficient tension force can be applied. Furthermore, since the area subject to earth pressure during oblique insertion is large, it is possible to install an anchor that is less deformed during ground leveling.

〔Example〕

The present invention will be explained in more detail below with reference to the drawings.

In the present invention, as shown in FIG. 2, a strip tension material I made of a steel plate or the like is used as the tension material. Thickness t in this case
0.6 to 'lQ*m, particularly preferably 1 to 1
0 dragon is used, and the width W is 50 dragon or more, especially 10 dragon
Those with 0 or more intoxication are used, and the upper limit is 300 cranes, and in some cases up to 1000 meters. Various lengths can be used, but the longest length is about 10 m due to ease of construction and restrictions on installation equipment due to construction being carried out on a slope.

Now, according to an example of insertion and installation to be described later, the strip-shaped reinforcing material 1 is inserted and installed, for example, from the slope of the cut natural ground 2 to a deeper depth along the expected slip line β, as shown in FIG.

During this insertion, the sheath 4 is used to cut off the edge of the tensile material 1 from the ground, except for the tip.

After insertion, the tip of the flat drilled hole S is filled with hardening material 6 such as mortar or cement paste to fix the tensile material 1 and other threads. After hardening of the hardening material 6, the tensioning material 1 is tensioned by a hydraulic jack or the like, and fixed by driving a wedge 8 into the pedestal 7 on the protective wall 3, for example.

As shown in Figure 3, when inserting the tension member at an angle, the wide side of the tension member faces upward to counteract earth pressure.

Various methods can be employed for inserting the tensile material and filling the hardening material.

4 to 12 show examples in which a hole is drilled using a casing and the tensile material 1 is inserted.

To explain this, a guide cell 10 is fixed to a scaffold (not shown) or the like outside the slope of the ground, and an air or hydraulic hammer 11 such as a Buehler type or Krutsub type that moves forward and backward in the long plane direction is installed on the guide cell 10. I'll keep it. Further, the band-shaped tensile material 1 is inserted into a flat rectangular casing 12 having a storage hole 12a, and a wide chevron-shaped tip shoe 13 is arranged at the tip of the casing 12. Furthermore, the proximal end of the casing 12 and the hammer 110 are removably connected via a connecting bracket 14.

On the other hand, pressure feed pipes 18, 18 are fixed to the casing 12, for example, at both ends of the storage hole 12a, by welding or by a holding seat 19, and the connecting parts 18a, 18a at the base are led out of the casing 12, and high pressure liquid, e.g. Connect it to the pressure supply source of high-pressure water W. Furthermore, a jet nozzle 21.21 is attached to the tip of the connecting pipe 18.18 via a couple 20.20.

These jet nozzles 21.21 are made to protrude forward from the tip of the casing 12, and the through holes 13c of the tip shoe 13,
, 13c.

The reinforcing material 1 is inserted into the casing 12 in advance using a punching and inserting machine using high-pressure water that involves press-fitting and impact, and the reinforcing material 1 is connected to the casing 12 by a removable pin 15 at the base of the reinforcing material 1, and the casing 12 is connected to the tip shoe. 1
3. Apply hammer force to the base end of the casing 12 with the hammer 11 while fitting the reinforcing member 1 into the rear recess 13a and connecting the tip of the reinforcing member 1 with the connecting pin 16 at the connecting protrusion 13b of the tip shoe 13. , the hammer II is advanced along the guide cell 10, and high-pressure water W is ejected from the ejection nozzles 21 and 21 to cut the ground and insert it to a predetermined depth.

Thereafter, the detachable pin 15 is pulled out, the hammer 11 is moved back along the guide cell 10, and the casing 12, the jet nozzle 21.21, and the connecting pipe 18.18 are pulled out, leaving the reinforcing material 1 and the tip shoe 13 in the ground.

A hardening material 6 is injected into the hole of the tensile material 1 to ensure adhesion to the ground. In the embodiment, an injection pipe 17 is connected inside the casing 12.

According to this embodiment, after the insertion and installation of the casing 12, the reinforcing material 1, and the tip shoe 13 are completed, the hardening material G is supplied from outside the slope to the injection pipe 17, guided into the storage hole 12a, and injected from the tip opening thereof. . This injection work is preferably carried out during the process of drawing out the casing 12, but it may also be carried out in a state where the casing 12, which is about to be drawn out, is facing the hole caused by the drawing. Alternatively, the hardening material G may be injected by inserting a separate injection hose into the hole from which the casing is pulled out, without attaching an injection pipe to the casing 12.

In the above example, insertion is possible even if the tip shoe 13 is not used and the tip of the casing is left blind or tapered, but as in the example, the width of the base end is thicker than the thickness of the reinforcing material 1. When the tip shoe 13 is used, it acts as a resistor for the band-shaped tensile material 1 when another mountain is about to collapse, and together with the injection effect of the hardening material G, a strong tension resistor can be constructed.

In addition to steel plates, the band-shaped tensile material used in the present invention may include other metal plates, striped metal plates with irregularities formed on the surface to increase adhesion, and surface treatments such as plating to improve corrosion resistance. You can use the following.

As the high-pressure liquid in the above example, various liquids such as water can be used, and particles such as abrasive grains may be mixed into the liquid to increase the drilling power.

The ejection pressure is 50 kg/ant or more, especially 200 kg/ant.
cnT or more is preferable. The form of the jet nozzle 21 is the fifteenth one.
It may also be a diagram.

In the above example, since the tip shoe 13 is used, the ejection nozzle 21 is positioned forward of the tip of the casing 12, but if the tip shoe 13 is not used, it is not necessary to protrude.

In the above example, it is not necessary to use high-pressure water for drilling.

Further, for drilling, a rotary impact type hole drill, a screw auger type hole drill, or the like can be used.

Examples of the former are shown in FIGS. 13 to 16. That is, the movable table 31 and the guide member 32 are mounted on the frame 30.
A cylinder 33 is provided with a movable table 31 fixed to the frame 30.
The movable table 31 is connected to the connecting portion 30 of the frame 30.
It is made to be able to freely move forward and backward while being engaged with a.

A holding body 34 is provided on the moving table 31, and this holding body 34
A Danza hole hammer 37, 37, 37 is attached to the tip of each drilling shaft 36A to 36C by a rod chuck 35.35° 35 integrated with the
Each drilling shaft 36A to 36C is connected with a connecting fitting 38, and a hammer bit 39A is attached to the tip of each drilling shaft 36A to 36C.
~ Install 39C. Each hammer bit 39A~3
9C, the first hole is drilled so that the drilling areas overlap, as shown in Figure 15.
As shown in Fig. 3, for example, by retracting the central hammer bit 39B (a swivel 40 is attached to the base end of each drilling shaft 36A to 36C, and drilling water W is sent from there to the drill bit 39A to 36C). Make it eject from the tip of 39C.

Reference numeral 41 denotes a hydraulic motor for rotating each of the drilling shafts 36A to 36C in the same direction, and its output is transmitted to the chuck 35 via a power transmission mechanism within the holder 34.

When drilling holes, each drilling shaft 36A to 36C is rotated while moving the movable table 31 to the left in FIG. Drill a hole.

After the drilling is completed, each of the drilling shafts 36A to 36C is pulled out, a band-shaped tensile material is inserted in its place, and the base end thereof is fixed to the slope of the ground as described above.

As shown in FIG. 17, an auger type drilling machine may be used.

50A to 50C are auger shafts.

Furthermore, a chain two type hole drilling machine or the like can also be used.

〔Effect of the invention〕

As described above, according to the present invention, the adhesion force between the hardening material and the tensile material is large, the fixing force and the proof stress during tensioning are increased, and the fixing force is firmly fixed to the ground. .

[Brief explanation of the drawing]

Fig. 1 is an overall view of the implementation state of the construction method of the present invention, Fig. 2 is a perspective view of a band-shaped reinforcing material, and Fig. 3 is a sectional view of an example of the structure of an anchor.
Fig. 4 is a perspective view of an example of a reinforcing material insertion device, Fig. 5 is a perspective view of only the casing in a pulled-out state, Fig. 6 is a diagram of how the tip shoe and the strip-shaped reinforcing material are connected, and Fig. 7 is a front view of the tip shoe. , FIG. 8 is a horizontal sectional view of the tip shoe and the tip of the casing, FIG. 9 is a side view thereof, FIG. 10 is a front view of the casing, FIG. 11 is a horizontal sectional view thereof, and FIG. 13 to 16 are horizontal sectional views of an example of a shoe at the tip, and FIGS. 13 to 16 are examples of a rotary impact type drilling machine. FIG. 13 is a plan view, FIG. 14 is a front view, FIG. 15 is a side view, and FIG. The figure is a perspective view, and FIG. 17 is a perspective view of an auger shaft of an auger type drilling machine. DESCRIPTION OF SYMBOLS 1... Belt-shaped tensile material, 2... Earth, 3... Protective wall, 4... Sheath, 5... Hole drilling, 6... Hardened material, 7
...Pedestal, 8...Wedge. Figure 3

Claims (1)

[Claims] (1) A flat hole is formed, and a band-shaped tensile material with a thickness of 0.6 to 20 mm and a width of 50 mm or more is inserted into the hole, and the tip of this tensile material is filled with hardened material. An anchor construction method characterized in that the anchor is anchored to the ground, and after the hardening material has hardened, the tensile material is tensioned and anchored to the surface of the ground.