JPH07229142A - Cutting device for temporary ground anchor - Google Patents

Abstract

PURPOSE:To efficiently heat a tension material in the case of cutting the tension material of a temporary ground anchor by heating. CONSTITUTION:A cutting device for a temporary ground anchor comprises tension materials 8 of plural carbon fiber reinforced plastic rods and fixers 9 which are connected to the forward ends of the tension members and fixed in the excavated hole in the underground, and is adapted to cut the tension member 8 of the temporary ground anchor 7 recovered after use, from the fixer 9, with the fixer 9 left behind. The cutting device further comprises a heat transmitter 21 in which an insert hole where all tension members 8 are inserted is bored, and by which a partial section of the tension member 8 is surrounded, and a heating unit 3 which is inserted in the heat transmitter 2 near the insert hole 21 and connected to an electric wire 4 connected to a power supply. The heating unit is caused to generate heat by an electric current flowing through the electric wire 4, thereby heating the tension members 8. Thus, the plural tension members 8 are heated efficiently.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cutting device for a temporary ground anchor, which is composed of a tensile member of a carbon fiber reinforced plastic rod and a fixing member, and which separates the tensile member of a temporary ground anchor used for temporary installation after use. Is.

[0002]

2. Description of the Related Art A ground anchor for temporary construction is recovered after construction, but a fixing member connected to the tip of a tension member is filled in a drilling hole and hardened. Since it has been fixed in, the extraction of the filler involves the destruction of the filler.

On the other hand, the applicant has made a practical application for a ground anchor which enables reuse of the tension material when the ground anchor is used for temporary construction by using a carbon fiber reinforced plastic rod as the tension material. -Proposed in No. 46033. This is a method in which a solenoid-shaped heating coil is wound around the tension material, and the tension material is directly heated so that it can be cut at the connection part with the fixing body. Is low.

This invention is a development of the above invention,
An apparatus for efficiently heating a plurality of tensile members is proposed.

[0005]

According to the present invention, all the tensile members are inserted into the heat transfer body, and the tension members are indirectly transferred by the heat generation of the heating element which is inserted into the heat transfer body and transfers heat to the heat transfer body. By heating at the same time, a plurality of tensile members are efficiently heated.

The cutting device has a through hole through which all the tensile members are inserted, and a heat transfer member surrounding a part of the tensile member and a heat transfer member near the insertion hole are connected to the electric wire connected to the power source. It consists of a heating element to be connected, and the heating element generates heat with an electric current flowing through the electric wire, and heats and pulls the tensile member.

The heat transfer body surrounds the entire tensile member, and the heat from the heating element is conducted to the entire tensile member through the heat transfer member, so that the entire tensile member is heated simultaneously and uniformly.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the drawings showing an embodiment.

The cutting device 1 of the present invention comprises a plurality of carbon fiber reinforced plastic rod tension members 8 as shown in FIG.
And a fixing member 9 which is connected to the tip of the fixing member 9 and which is fixed in the drilled hole in the ground. By heating the tension member 8 of the temporary ground anchor 7 which is recovered with the fixing member 9 left after use, Is separated from the fixing body 9.

As shown in FIGS. 1 and 2, the cutting device 1 has a through hole 21 through which all the tensile members 8 are inserted, and the heat transfer body 2 surrounding a part of the tensile member 8 and the through holes 21. Near heat transfer body 2
It is composed of a heating element 3 which is inserted therein and to which an electric wire 4 connected to a power source is connected. The heating element 3 generates heat and heats the tensile member 8 to break it. A metal or non-metal heating element is used as the heat transfer element 2 and the heating element 3.

1 and 2 show an insertion hole 22 into which the heating element 3 is inserted at the center of the cross section of the heat transfer element 2, and an insertion hole around the insertion hole 22.
This is an example in which the insertion hole 21 through which the tension member 8 is inserted is arranged so as to surround 22. However, the heating element 3 is inserted into the insertion hole 22 and leakage current is generated around the portion protruding from the heat transfer element 2. A protective insulator 5 surrounds and is further protected by an insulating skin 6.

The heating element 3 generates heat by the electric current flowing through the electric wire 4 and conducts to the heat transfer element 2 to heat the tension member 8. The tension member 8 is deteriorated by heating a section through which the heat transfer body 2 is inserted, and is broken by receiving a tensile force, so that the fixing member 9 is broken.
Separated from and pulled out.

3 and 4 show an embodiment in which a plurality of insertion holes 22 are evenly arranged on the outer periphery of a plurality of insertion holes 21, in which case the heating elements 3 are arranged in parallel by the electric wires 4. Connected.

[0014]

The present invention is as described above. Since all the tensile members are inserted into the heat transfer body and the heat generated by the heating element inserted into the heat transfer body heats the tensile members at the same time, a plurality of tension members are used. The tensile member can be efficiently heated.

[Brief description of drawings]

FIG. 1 is an elevational view showing a cutting device.

FIG. 2 is a plan view of FIG.

FIG. 3 is an elevational view showing another cutting device.

FIG. 4 is a plan view of FIG.

FIG. 5 is a cross-sectional view showing an installed state of a temporary ground anchor.

[Explanation of symbols]

1 ... Cutting device, 2 ... Heat transfer body, 21 ... Insertion hole, 22 ...
Insertion hole, 3 ... Heating element, 4 ... Electric wire, 5 ... Insulator, 6
…… Skin, 7 …… Temporary ground anchor, 8 …… Tensile material, 9
...... Fixed body.

Claims (1)

[Claims] 1. A carbon fiber reinforced plastic rod comprising a tensile member and a fixing member connected to the tip of the rod and fixed in a hole drilled in the ground. The fixing member is recovered after use. It is a cutting device that separates the tension material of the temporary ground anchor from the fixing body.The heat transfer body that has a through hole through which all the tension material is inserted and surrounds a part of the tension material and the heat transfer body near the insertion hole. A cutting device for a temporary ground anchor, which is composed of a heating element connected to an electric wire connected to a power source, the heating element generates heat by an electric current flowing through the electric wire, and heats and breaks the tensile member.