KR20000047445A - Fixing unit for removing tension bar for a ground anchor - Google Patents

Abstract

PURPOSE: A fixative for removing tension member of ground anchor is provided; the improvement in manufacture and assembly by reducing the number of components; a decrease of the production cost; lightening; the improvement in reliability on removing tension member; miniature of anchor hole; removal of tension member from ground anchor without an exclusive pull-out device. CONSTITUTION: At removal of tension member by adjoining more than two tension members, inserted from the rear of a main body (1), to the wedge of a main body and dismantling the wedge for tension member by operation from anchor hole external, this fixative comprises the steps of; forming a sill (11) for putting a wedge-box stand (2) on the lower end of a main body (1); on a sill (11), punching a wire hole (12) for a wire of a wedge-box stand and putting a donut-shaped wedge stand (2) having electric element connected to pyrolyzed thermoplastic resin; inserting a wedge box (3), formed wedge grooves (34) on a taper hole (22), to a main body (1) and putting on a wedge-box stand (2); inserting a wedge (4), formed same quantity of wedge grooves (34) as wedge grooves (34) on outer taper side (41), to a wedge box (3) and placing on a wedge-box stand (2); fixing a cover 95) on the front part of a main body (1); putting a bolt (6) into a hole in the center of a cover (5) and connecting to the front part of a wedge (4).

Description

Fixing unit for removing tension bar for ground anchors {Fixing unit for removing tension bar for a ground anchor}

The present invention relates to a fixing agent for removing the tension member of the ground anchor, and more particularly, to improve the fabrication and assemblability according to the reduction of the number of parts, to reduce the manufacturing cost, to reduce the weight, to improve the reliability of removing the tension material, to reduce the anchor hole, and The present invention relates to a tension member-removable anchor body of a ground anchor which enables to easily remove a tension member without a dedicated drawing machine.

Ground anchors (aka earth anchors) are widely used in the earthwork method required for earthquake construction, which prevents the ground from collapsing while performing excavation work for underground structures to construct or build construction and civil structures.

Ground anchors for this purpose include compression type, tension type and acupressure type. Tensile ground anchors are the most widely used type of ground anchors, but they cannot remove the tension member, and the ground anchors are difficult to remove because they are constrained by tip pressure.

In addition, in terms of securing the anchoring force, the tension-type anchor anchor is reduced in the anchoring force due to the tensile cracking of the grouting body over time, and the anchoring anchor is applicable only to the rock which is capable of tip acupressure.

In any case, ground anchors use anchoring materials (steel wires) with excellent tensile strength to insert anchor bodies into anchor holes drilled in the ground, and to secure the anchoring force by applying load to the free long end, and use the anchoring force to drill deep underground. In order to secure safety at the time of construction, stabilization wall, ie, temporary earth wall, installed on the excavation surface will be stabilized.If the tension material is left in the ground after the construction work on the underground structure is completed, when the underground structure for the adjacent ground is constructed in the future As an obstacle to the construction, not only civil complaints occur, but also a construction cost for removing the tension member is added.

Ground anchor anchors have been proposed to solve this problem. A representative example thereof is Patent Publication No. 96-4273. This prior art has a main body where wedge seats are formed at each circumferential surface of a hollow inner circumference, a solar wedge which inserts a split wedge into a split center material to sandwich a central tension member, and a wedge seat around the sun wedge. Satellite wedges, the center wedge into which the solar wedges are inserted, and the same number of spacers as the satellite wedges sandwiched therebetween so as to maintain their position, the top cover of the sun wedge and the satellite wedges, and the body Consists of a cap to cover.

However, in addition to the satellite wedge tensioning member that exhibits substantially tensile force, the internal fixing member is a component of the underground anchor by making the towing tension tensioning member for removing the tensioning material, i.e., the tensioning tensioning member to be fitted to the solar wedge, and the wedge clamping it as an essential component. Increasing the number and the increase in manufacturing costs due to the addition of the tension pulling material, there is a disadvantage that the drawing work of the pulling material for pulling is added.

In addition, the inner surface of each spacer is given a taper corresponding to the tapered center material, and the side surface is given a taper corresponding to the taper of two adjacent satellite wedges, and the outer surface is too complicated to have an arc surface corresponding to the hollow of the body. Processing and assembly difficulty is high.

In addition, since the sun wedge and satellite wedge are three-segment type, to maintain the shape of the combination wedge from before assembling the inner fixture to after assembly, the wedge assembly is fitted with an elastic ring to maintain the intact shape of the wedge assembly. Should be. Because of this necessity, the ring ring groove for the elastic ring is machined on the outer circumferential surface of each wedge member.Machining such a ring groove on the outer circumferential surface of the split wedge is not difficult for machining. It is very inconvenient to snap a tension member because it becomes an obstacle to fit.

In the main body, a ring groove is made at the rear of the center hole drilled in the axial direction at the center thereof, and a C-shaped stop ring for the center material is inserted so that the center material inserted into the center hole does not fall to the rear of the main body while the tension force is not applied. This has the disadvantage that the internal structure of the complex is further complicated and the number of labor is increased.

In addition, the core member may slip off when the pulling force is applied to the pulling member if the pulling member is loosely snapped to the solar wedge by an operation mistake before removing the tension member. If this is the case, the core wedges drawn by the solar wedge will not retreat, so that the satellite wedges will not open and all tension members will be inseparable, and conventional tension remover internal fixtures do not use dedicated drawers. Without it, the tension member cannot be removed.

The object of the present invention is to remove the tension member easily without removing the sun wedge and the center member, the tension member for the center material traction, can be applied regardless of the ground, easy to manufacture and field assembly, the drilling diameter It is to provide a fixing agent for removing the tension member of the ground anchor that can be made small.

1 is a partially disassembled exploded view of an anchor body according to the present invention

2 is a front view of the wedge tube stand according to another embodiment

Figure 3 is a plan view of the wedge is inserted into the wedge container inserted into the main body

4 is a longitudinal cross-sectional view of an anchor body bitten by a tension member;

5 is a thermoplastic resin of the wedge tube support as the electric heating element is energized

The situation at the time of the initial pyrolysis

Figure 6 is a situation when the wedge bite for the tension member is released by the thermal decomposition of the thermoplastic resin of the wedge tube support

Explanation of symbols for the main parts of the drawings

1: body 2: wedge support

3: wedge bucket 4: wedge

5: cover 11,32: step

12: electrician 13: external thread

21 thermoplastic resin 22 electric heating element

23: wire 33: taper hole

34,42: wedge groove 41: tapered surface

43: screw groove 51: bolt ball

The object of the present invention is to provide a main body perforated wire hole for drawing out the front end of the wedge barrel support to form an annular step that can seat the wedge barrel support at the bottom of the inner peripheral surface, the outer diameter It is a donut shaped like the inner diameter of the main body.The electric heating element is embedded in a thermoplastic resin that is thermally decomposed and melted or vaporized when subjected to high heat, and the wedge tube stand with which the wire connected thereto is drawn to the bottom of the wedge tube support is caught on the step. The wedge groove is seated and the wire is drawn out by the electric wire worker, and the wedge tube formed with the semicircular wedge groove is formed on the tapered inner circumferential surface and the wedge groove corresponding to the wedge groove on the reverse tapered outer circumferential surface. The formed wedge is inserted into the wedge tube so that the tension member can be inserted into each wedge groove matched with each other, and the inner circumferential surface of the main body However there is a covered and sandwiched between the bolt in the middle of a ground tension member removed for the fixing of the fastening anchor on the wedge as the main characteristic.

As a result, the solar wedge, the core material supporting it, the tension member for the towing of the core material and the detachable piece wedge are excluded, so the number of internal parts is simple, the structure is simple, fabrication and assembly is easy, and it is light and easy and reliable only by manpower without using a dedicated drawing machine. It is possible to provide a ground anchor that can remove the tension member.

In addition, unlike the conventional anchor body in which wedge-shaped wedges are applied to each wedge seat, the one-piece wedge that excludes the sculpted wedge and pushes all the tension members at one time reduces the outer diameter of the wedge container corresponding to the volume of the conventional wedge. It is possible, and also according to this, the hole diameter of the anchor hole is small, so that the drilling operation is easy and the drilling cost is also reduced.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

In Fig. 1, the fixing agent for removing the tension member of the ground anchor of the present invention is composed of a main body 1, a wedge container support 2, a wedge container 3, and a wedge 4 and a cover 5.

The main body 1 is a kind of flat tube having a front and back drilled, and an annular step 11 is formed at the lower end of the inner circumferential surface, and an electric wire hole 12 drilled in the axial direction is formed on the step 11, and the lower end body is located at the lower end of the outer peripheral surface. A fastening outer thread 13 is provided, and an outer thread 14 for fastening the cover is attached to the upper end of the outer peripheral surface.

The step 11 is a seat where the wedge tube base is seated, the wire hole 12 is a hole through which the wire of the wedge tube base passes, and the outer thread 13 has a frictional force with the cement paste placed in the anchor hole on the outer circumferential surface thereof. It is a fastening part for fastening a load-bearing body to increase or inserting a polyethylene resin hose that prevents foreign substances such as earth and sand from entering.

The wedge tube support 2 is an electric heating element 22 embedded in the thermoplastic resin 21, and the wire 23 is drawn out from the electric heating element 22, the outer diameter is the same as the inner diameter of the main body 1 and the inner diameter is The same diameter as the outer diameter of the lower end of the wedge tube 3 allows the thermoplastic resin 21 to be crushed evenly between the main body 1 and the wedge tube 3 so that the thermoplastic resin 21 is crushed even at a high fixing pressure. I cannot let you go through the gap of the inside.

The thermoplastic resin 21 is a resin that is maintained as a very solid solid at room temperature and is thermally decomposed and melted or vaporized once subjected to high heat. Such resins include polyamide-based MC nylon (trade name), polyacetal resins, polycarbonate resins, and the like.

The thermoplastic resin 21 must be seated without leaving a gap between the step 11 and the inner circumferential surface of the upper body 1 and the bottom of the wedge container 3 to withstand the high settling load transmitted through the tension member. It is preferable to perform precision processing so that it may not be pushed out.

The electric heating element 22 is a heating source for heating and thermally decomposing the thermoplastic resin 21, and is attached to the bottom surface of the thermoplastic resin 21 or placed in a mold when the thermoplastic resin 21 is molded to be integrated.

The wire 23 is drawn out to the outside of the anchor hole and then connected to the external power source to energize the electric heating element 22.

In FIG. 2, the wedge tube holder 2 according to another embodiment attaches the insulating plate 24 to the upper and lower surfaces of the thermoplastic resin 21. The insulating plate 24 is electrically isolated from the heating element 22 and the bottom 11 of the wedge case 3 and the step 11 of the metallic body 1 to energize the heating element 22 to remove the tension member. This is to ensure safety from the risk of electric shock and electric shock due to leakage of time, but it is not necessary.

The reason is this. That is, in the initial stage when the electric heating element 22 is energized, the surrounding thermoplastic resin 21 is first thermally decomposed and escapes to prevent contact between the electric heating element 22 and the main body 1 and the wedge tube 3 to insulate it. In addition, it is not necessary to apply the insulator 24, since the residuals that are not pyrolyzed also serve as the insulator, but should be applied when a short circuit is feared in case of emergency.

In FIG. 1 again, the wedge barrel 3 restrains the tip of the tension member sandwiched between the wedge 4 in the body 1 and then sits down when the wedge holder base 2 is pyrolyzed to reduce the volume, When the restraint force is reduced, the tension member is inverted into a recoverable state, and the outer diameter is equal to the inner diameter of the main body 1, and the tube shaft 31 given below the outer circumferential surface is the same as the inner diameter of the step 11 so as to be closely inserted. And the step 32 is provided where the tube shaft 31 starts. The step 32 is a flat surface corresponding to the top surface of the wedge tube support 2 corresponding to the step 11 of the main body 1. In addition, the upper half of the inner circumferential surface is a taper hole 33, and a wedge groove 34 having a semi-circle shape or less is formed at the place where the circumference of the taper hole 33 is equally divided to cooperate with the wedge groove 42 of the wedge 4 side. To fix the tension member.

The wedge 4 is to press and fix the tension member enclosed in all the wedge grooves 34 of the wedge barrel 3 at the same time to the outside, the tapered surface 41 of the outer circumference having the same gradient as the taper hole 33 in the outer circumference The wedge groove 42 of the semicircle or less corresponding to the wedge groove 34 is formed in the same number, so that the tension member is easy to be contaminated, and the center of the upper surface is provided with a screw groove 43 to form a bolt on the cover 5. It is an inverted cone shaped to be fastened with

The lid 5 stabilizes the wedge 4 while the tension member is sandwiched between the wedge container 3 and the wedge 4 and the thermoplastic resin 21 of the wedge container support 2 is thermally decomposed to reduce the volume. When the wedge container 3 sits down, it prevents the wedge 4 from following the wedge container 3, and when the anchor is inserted into the anchor hole until the recovery of the tension material, As a function of preventing foreign matters from entering the ground, such as rubble and gumfire, the inner screw 52 for fastening to the outer thread 14 given to the upper part of the main body 1 is provided.

In addition, if the cover 5 moves while the wedge 4 is fixed to the cover 5, the wedge 4 may flow and the fixing state of the tension member may become unstable, and the thermoplastic resin 21 is thermally decomposed. As the volume decreases, the bolt hole 51 is drilled in the center of the plate surface and fixed to the screw groove 43 of the wedge 4 so as to prevent movement with the wedge container 3. To be able.

With reference to FIG. 4, the assembly procedure which pinches a tension material to an anchor body is demonstrated. The wedge tube base 2 into which the electric wire 24 is moved to the rear end is inserted into the main body 1, which contains nothing, and is seated on the step 11. At this time, the wire 23 is pulled out by the wire hole 12 to connect the conductive wire (e) having a length more than the anchor hole.

Sit the wedge canister (3) over the wedge canister (2). Inserting the wedge cylinder 3 by applying a pressure greater than the rated load of the anchor body helps to prevent deformation of the thermoplastic resin 21 when the anchor body is installed in the anchor hole in the ground and the fixing load is applied.

On the other hand, the tension member (a) is bundled in equal numbers with the wedge grooves (34, 42), and the tip of the bundle of tension member (a) is pushed in through the rear end of the main body (1) and the tube shaft (31) of the wedge barrel (3). Each wedge groove 34 is seated one strand of tension (a).

Subsequently, the wedge 4 is inserted into the wedge groove 34 of the wedge tube 3 so that the wedge groove 42 coincides with the wedge groove 42. Then, the wedge 4 is applied in the insertion direction so as to bite the tension member a, and the cover 5 is put on the tip of the main body 1. At this time, it is stable that the bottom surface of the lid 5 is pressed against the top surface of the wedge 4. This is because if the lid 5 does not contact the wedge 4, the wedge 4 may recede toward the lid 5, and the force after the tension member a is opened may be weakened.

Then, the bolt 6 with the head is inserted into the bolt hole 51 of the lid 5 and fastened to the screw groove 43 of the wedge 4, and the edge of the bolt hole 51 and the main body 1 are fastened. Apply sealant to the edges to make it waterproof. Finally, the front end of the lower body (b) through which the tension member (a) is penetrated to the outer thread (13) given in the lower part of the main body (1), and the bundle of the tension member (a) has a soft synthetic resin tube (c) longer than the tension member. After covering, the front end of the synthetic resin tube (c) is covered with a band (d) so as not to fall off by covering the rear end of the lower body (b), and if necessary, the front end of the synthetic resin tube (c) is sealed to enhance waterproofing.

Next, a method of removing the tension member will be described with reference to FIGS. 5 and 6.

The anchor body, which is bound to the grout in the anchor hole, receives a strong tensile force at the time of anchoring, and is fixed as a separate anchor head, that is, an external anchorage, at the fixed end of the ground, earth wall, earth wall pile, or belt supporting the anchor body. . Follow-up or after the ground anchors have been used to prepare for removal of the tension member.

When the conducting wire e connected to the electric wire 24 and drawn out to the external fixing unit (not shown) is electrically connected to an external power source, the electric heating element 22 generates heat to thermally decompose the thermoplastic resin 21. The thermoplastic resin 21 is softened toward the outer portion at the portion in contact with the electric heating element 22 to gradually be thermally decomposed to melt or evaporate, and some of the thermoplastic resin 21 is changed to a liquid phase to generate fluidity.

The thermally decomposed thermoplastic resin (21a) is pressed by the force pulled by the tension force applied to the tension member (a) is pushed out of the gap between the remaining electric wire hole 12 is occupied by the electric wire is taken out of the main body (1) It accumulates in the lower space 15. And the thermoplastic resin 21 is melted and reduced by the amount of the outflow volume and the volume decreases, the wedge container 3 is subject to the tension of the tension member (a) to fall. However, since the wedge 4 is fixed to the cover 5 fixed to the main body 1 with the bolt 6, the wedge 4 does not follow the wedge container 3 that sits down and stays intact without departing from the original position.

This change is followed by the wedge barrel (3) and the wedge (4) between the gap, the wedge groove (34, 42) the force holding the tension member (a) is gradually weakened. When the wedge bite falls below the tensile force acting on the tension member (a), the tension member (a) starts to slide in the direction in which the tension member (a) contracts in the wedge grooves (34, 42).

Then, at the moment when the elongation according to the settling load of the tension member (a), that is, the contraction force, surpasses the bite pressure established between the wedge barrel (3) and the wedge (4), the tension member (a) is extremely instantaneously wedge grooves (34, 42). ) And slide out and stay in the plastic pipe (c). The tension member staying in the plastic pipe (c) stays so free that it can be easily pulled out by a single person outside the anchor hole. Thus, the tension member can be removed without having to mobilize heavy equipment such as a drawing machine or a crane.

According to the present invention as described above, due to the thermal decomposition of the thermoplastic resin by the heating of the electric heating element is discharged in place by the settling load of the tension member acting on the wedge cylinder and the volume is reduced while the wedge cylinder is settled while the wedge cylinder is down, The tensioning force of the wedge and the center for supporting the tensioning material of the ground anchor is the anchoring material of the ground anchor, which causes the tensioning material to slide out of the wedge groove due to the contraction action caused by the anchoring load. The elimination of tensioning materials and separable wedges for traction of materials and cores results in a simple structure due to the low number of built-in parts, easy to manufacture and assemble, and a ground anchor that can be easily and reliably removed by manpower without the use of dedicated drawing machines. Can be provided.

In addition, unlike the conventional anchor body in which wedge-shaped wedges are applied to each wedge seat, the one-piece wedge that excludes the sculpted wedge and pushes all the tension members at one time reduces the outer diameter of the wedge container corresponding to the volume of the conventional wedge. And it is also very useful invention, such as to give a profit, such as the hole diameter of the anchor hole is also reduced to facilitate the drilling operation and the drilling cost is reduced.

Claims (1)

Two or more tension members inserted into the rear of the main body by wedges in the main body and the wedge of the tension member by the operation outside the anchor hole to remove the tension member, the wedge tube at the bottom of the inner peripheral surface of the main body (1) An electric heating element 22 having a bearing saddle step 11 formed therein is formed on the stepped hole 11, and a wire hole 12 for penetrating the wire of the wedge tube support is connected to the thermally decomposable thermoplastic resin 21. A wedge tube (3) in which a donut-shaped wedge tube support (2) embedded in the stepped portion (11) is seated, and a tapered hole (33) forms wedge grooves (34) or less in a semicircle wherever the circumference is divided. (1) is inserted into the wedge barrel support (2), the wedge groove (4) having the same wedge groove (42) is formed on the tapered surface 41 of the outer periphery of the wedge container Insert into (3) and sit on wedge support (2), and put cover (5) on the tip of main body (1) And cover 5 middle of the bolt hole 51 bolt (6) by inserting the tension member removal-type ground Ke keoyong anchor body, characterized in that fastened to the upper end of the wedge 4 in the perforation of the.