KR20070026953A - Prestressing lock bolt apparatus - Google Patents

Abstract

A lock bolt apparatus is provided to reduce the constructing time without the hardening time by increasing the stability of the slope through the constraint effect. A lock bolt apparatus is composed of a special shaped hollow pipe(10) formed with an uneven part on the outer surface; an extension claw(20) radially extended at one end of the special shaped hollow pipe; a tension member(30) installed by penetrating the special shaped hollow pipe and the extension claw; a cone-shaped body inserted in the cone-shaped inner surface of the extension claw; a compressive plate(50) formed with a tension member hole in which the tension member is penetrated; and a fixing device(60) installed at the rear end of the tension member to keep the tension member in the tensioned condition.

Description

Prestressing lock bolt apparatus

1 is a schematic view showing a load-loaded lock bolt device according to the present invention;

Figure 2a is an exploded perspective view showing the buried fixing portion in the drilling hole in the preload load-type lock bolt device according to the present invention,

FIG. 2B is a cross sectional view of FIG. 2A;

2C is a cross-sectional view taken along the line A-A of FIG. 2B;

Figure 3 is an exploded perspective view showing the outer mounting portion of the drilled hole inlet in the preceding load-loaded lock bolt device according to the present invention,

Figures 4a to 4d is a process diagram showing the process of construction using the preloaded lock bolt device according to the present invention,

Figure 5 is a cross-sectional view showing another embodiment of the outer mounting portion of the drilled hole inlet in the prior load-loaded lock bolt device of the present invention.

<Description of the symbols for the main parts of the drawings>

10: release hollow pipe 20: expansion tank 21,62a: tension material

22, 62b: Cone inner surface 23: Expansion tank fixing ring 24: Flange

24a: guide groove 26: guide pin 28: flange cap

30: tension member 40: cone-shaped body 41: fastener

50: acupressure plate 54,72: grout inlet 60: anchorage

62: fixed body 64: wedge 68: cap

70: packer

The present invention relates to a lock bolt device used for a rock having a discontinuous surface, and more particularly, because the outer surface is extended in a radial radial cylindrical shape of the same diameter is fixed over a wider area on the inner surface of the drilling hole excellent fixing force When the preceding load is applied, the safety of the slope is strengthened by the restraint effect on the discontinuous surface of the rock, so the additional load can be immediately excavated without the curing period of the grouting material. It is about.

In general, the lock bolt is a method of drilling a rock to a rock, such as underground structures, tunnels, etc. with a predetermined diameter, and locks the lock bolt into the drilling hole. Such a lock bolt drills a hole in the ground including mountain rock in civil construction work, especially in tunnel work. The explosives, such as dynamite, for example, explode in the perforated holes to break the rock and widen the base hole, and then drill the foundation tunnel at a certain height and width, and then disintegrate the foundation tunnel. In order to prevent the ingot, a number of rock bolts (base bolts) are put on the inner side of the foundation tunnel, a grid mesh is installed, and concrete is finally poured to perform reinforcement film construction.

The reinforcement film construction, first drilled the hole for the rock bolt to be inserted into the rock by using a rock drill or crusher, and then cast cement mortar as a grouting material in the drilled hole and insert the lock bolt or insert the rock bolt In the case of pouring the cement mortar, the lock bolt is firmly fixed in the rock. In this case, the lock bolt is installed at predetermined intervals so that the lock bolt is sufficiently endured while maintaining the fixed load.

However, in such conventional lock bolts, cement mortar is placed in the drilled hole and waited until the cement mortar is cured, and then the lock bolt is firmly fastened to the pressure plate. After checking whether it can be supported through the drawing test and installing various materials or structures, it takes a long period of construction and has a problem of installing a plurality of lock bolts to improve bearing capacity.

Ground reinforcement methods using a rock bolt or a device to reinforce using such a lock bolt is continuously being developed, for example, 'locking rock assembly for a rock bed rock' is presented in Korean Patent No. 108419.

As can be seen by the claims, the tunnel rock layer is composed of a bolt body having a tapered first wedge member at the front end and a rear end spiral portion at which the nut is fastened to the rear end, and an expandable bushing expandable by the wedge member. In the fixing lock bolt assembly, an extension bushing inserted close to the first wedge member of the bolt body is formed in a tubular shape, and a plurality of toothed rings of helical inclined in one direction are formed on the outer surface of both ends and cut in the longitudinal direction to obtain several It has a toothed tube composed of an extension piece, and a tapered wedge connecting surface is formed on both sides thereof, and a tapered second wedge member is inserted into the rear side of the expansion bushing inserted into the bolt body and opposed to the first wedge member. And it is characterized in that the drive tube for driving the second wedge member forward driving to the expansion bushing side.

In the patent of the above configuration, the first wedge member is integrally formed in the bolt body, and it is difficult to manufacture, and even if separately provided, the manufacturing process such as the screw fastening method or the need to integrate by welding is complicated and cumbersome. there was.

In particular, the first wedge member at the end of the bolt body and the second wedge member pushed by the drive tube expand the extension piece in the radial direction of the outer part, but the extension piece which is a plurality of pieces cut radially in both sides of the expansion bushing is integrally provided. Therefore, the end is extended like a cone (cone), and because of this, the inner peripheral surface of the drilling hole and the entire extension piece does not come in contact with the surface, so that the fixing force is somewhat weak, there is a problem in that the tension is applied to the bolt fuselage.

The present invention has been made to solve the problems of the conventional rock bolting method that is constructed at the time of tunnel excavation or rock construction, the object is to extend the expansion tank to the outside while pulling the cone-shaped body mounted on the end of the tension member In other words, the outer surface is extended to the radially cylindrical shape of the same diameter, and is fixed to the inner surface of the drilling hole over a larger area, thereby improving the fixing force more prominently, and the safety of the slope due to the restraint effect on the discontinuous surface of the rock by giving the preceding load As it is strengthened, it is possible to provide additional excavation work immediately without curing period of grouting material, thus providing a preloaded lock bolt device that can shorten the construction period.

Another object of the present invention is to install a packer at the inlet of the hole in the loading stage of the preceding load so that pressure grouting is performed in a state where the ground is constrained, and after the grouting is performed, the release hollow pipe exerts a lock bolt function to reinforce the ground To provide a maximum load-loaded lock bolt device to maximize.

In order to achieve the above object, the preceding load-loaded lock bolt device according to the present invention includes a hollow hollow pipe having irregularities formed on an outer surface thereof; An expansion tank installed radially at one end of the release hollow pipe and formed of a tension material hole and a cone-shaped inner surface in a center line direction, having an equal angle and divided into three or more; A tension member installed through the release hollow pipe and the expansion tank; Cone-shaped body fixed to the end of the tension member is inserted into the cone-shaped inner surface of the expansion tank; A pressure plate which supports the other end of the release hollow pipe and has a tension material hole through which the tension material penetrates; It is installed on the end of the tension member drawn out through the release hollow pipe and the pressure plate, characterized in that it is provided including a fixture for maintaining the tension member in the tensioned state.

To achieve smooth expansion of the expansion tank, a flange having a guide groove formed radially with an equiangular number as the number of divisions of the expansion tank is fixed, and through the guide groove of the flange, each expansion tank can be moved radially. The guide pin is fastened and the flange may be covered with a flange cap to prevent foreign matter from penetrating into the guide pin and the guide groove.

An expansion tank fixing ring such as a band or wire, which can be cut by a predetermined expansion external force, may be fastened to the expansion tank without interfering with the operation when transporting or inserting the lock bolt device into a boring hole such as a rock. Can be.

A packer is provided between the end of the release hollow pipe and the pressure plate to block the inlet of the hole while supporting the end of the release hollow pipe. The packer and the pressure plate are provided with two grout inlets for injecting grouting material into the hole and removing foreign substances. It features.

The anchorage includes a fixed body having a tension member hole and a cone-shaped inner surface, three or more wedges inserted into the cone-shaped inner surface of the fixed body to secure the tension member, and a cap fastened to the fixed body to cover the ends of the wedge and the tension member. It consists of.

According to the present invention, the load-loading lock bolt device of the present invention having the above-described features extends the expansion tub to the outside while the cone-shaped body mounted at the end of the tension member is pulled out, that is, the outer surface of the drill hole is radially expanded to have the same diameter. It is fixed over a larger area on the inner surface, which improves the fixing force more prominently. When the preceding load is applied, the safety of the slope is strengthened by the restraint effect on the discontinuous surface of the rock, so additional excavation work is possible without the curing period of the grouting material. Since the construction period can be shortened, the construction cost is reduced and the work efficiency is improved.

Hereinafter, the configuration and operation of the prior load-loaded lock bolt device of the present invention will be described in more detail with reference to the accompanying drawings.

1 is a block diagram schematically showing a preloaded lock bolt device according to the present invention, Figures 2a to 2c is a view showing a buried fixing portion in the drilling hole in the preloaded lock bolt device according to the present invention, Figure 3 is an exploded perspective view showing the outer mounting portion of the drilled hole inlet in the preloaded lock bolt device according to the present invention.

As shown in the figure, the prior load-loaded lock bolt device of the present invention is provided with an elongated hollow hollow pipe 10 having irregularities formed on the outer surface thereof in order to improve adhesion to the grouting agent, and the hollow hollow pipe 10 of the One end is provided with an expansion tank 20 extending radially while being guided through the flange 24, the expansion tank 20 is formed with a tension hole 21 and the cone-shaped inner surface 22 in the centerline direction It is divided into three with equal angles.

The release hollow pipe 10 and the expansion tank 20 at one end thereof is provided with a tension member 30 penetrating through the inside thereof, and the cone-shaped inner surface 22 of the expansion tank 20 at the end of the tension member 30. Cone-shaped body 40 to be inserted into the installation is fastened and fixed, the cone-shaped body 40 is inserted into the wedge 42 divided into three into the cone-shaped body 40 to be located outside the tension member 30 and The wedge 42 is fixed by a fastener 41 which is screwed with the cone-shaped body 40.

The expansion tank 20 has been shown to expand three fan-shaped shape centering on the tension member hole 21 into which the tension member 30 is introduced, that is, a configuration that extends outward when tensioning the tension member 30, The number is not limited because it may be composed of three or more expansion tanks.

In the flange 24, the guide groove 24a is radially formed at an equal angle to the number of divisions of the expansion tank 20 so as to smoothly expand the expansion tank 20, and the guide groove of the flange 24 The guide pins 26 are fastened so that each of the expansion tanks 20 can move radially through the 24a, and foreign matter does not penetrate the guide pins 26 and the guide grooves 24a to the flange 24. The flange cap 28 is covered. When the flange cap 28 is covered on the flange 24 as described above, even if cement mortar, which is a grouting material, is injected into the drilling hole h, the expansion tank 20 is not damaged at all, and precedes the drilling hole h. When loading the expansion tank 20 of the load-loading lock bolt device, it can be easily loaded without being disturbed.

On the outer surface of the expansion tank 20 by a predetermined expansion external force to the expansion tank 20 without interrupting the operation when loading or loading the load-loaded lock bolt device into the drilling hole (h), such as a rock It should be fastened to the expansion tank fixing ring 23, such as a band, wire, etc. that can be cut.

The other end of the release hollow pipe 10 is provided with a pressure plate 50 having a tension hole 52 through which the tension member 30 penetrates, and passes through the release hollow pipe 10 and the pressure plate 50. At the end of the drawn tension member 30, a fixing unit 60 is provided for maintaining the tension member 30 in a tensioned state.

The fixing unit 60 is provided with a fixing body 62 having a tension member hole 62a and a cone-shaped inner surface 62b, and penetrated through the tension member hole 62a to the cone-shaped inner surface 62b of the fixing body 62. Three wedges 64 are inserted to fix the tension member 30, and the cap body 68 covers the end of the tension member 30 so that the wedge 64 is not detached from the fixing body 62. Is fastened. In addition, between the fixed body 62 and the cap 68 is provided with a mesh hook 66 for hanging and fixing the net is covered on the incision surface.

It will be described the construction process using the preceding load-loaded lock bolt device according to the present invention configured as described above. First, the drilling hole (h) in which the preceding load-loaded lock bolt device of the present invention can be inserted into the discontinuous rock surface during the tunnel excavation or rock construction, as shown in FIG. 4A, and then into the drilling hole (h). After loading the load-loading lock bolt device as shown in FIG. 4B, the end portion of the tension member 30 protruding from the outside of the drilling hole h is the tension member hole 52 and the fixed body 62 of the pressure plate 50. The wedge 64 is pulled so that the tension member 30 is pulled through the inner side of the wedge 64 inserted into the tension member hole 62a and the cone-shaped inner surface 62b of FIG. Push in to fix it.

At this time, when the tension member 30 is pulled, the expansion tank 20 at the end of the release hollow pipe 10 is expanded by the cone-shaped body 40 at the end of the tension member 30, and thus the tension member is fixed to the inner surface of the drilling hole h. Since the load is applied to 30 and the tension force is maintained, another excavation can be performed even before the grouting material is injected and cured.

In this way, pulling tension member 30 to give tensile force without injecting grouting material into the drilling hole h is a preceding load. When a load is applied to a rock on which discontinuous cracks are formed, the load on the rock surface is supported. do.

In more detail the process of the preceding load-loaded lock bolt device of the present invention is loaded with the preceding load, as the tension member 30 is pulled, the fastener 41 and the cone-shaped body 40 coupled to the end of the tension member 30 ) Is naturally drawn into the cone-shaped inner surface 22 side formed in the inner side of the expansion tank 20 is to expand toward the outer surface, that is, the inner surface of the drilled hole (h), the expansion When the tub 20 is expanded, the outer circumferential surface of the expansion tub 20 comes into contact with the inner surface of the drilling hole h, and thereafter, as the expansion tub 20 is further expanded, the tension hole 30 is stretched in the process of tensioning the tension member 30. The expansion tank 20 is firmly fixed to the inner surface of the drilling hole h while being drilled into the inner surface of (h).

As the expansion tank 20 is fixed to the inner surface of the drilling hole (h) as described above, the load applied to the rock of the discontinuous surface before the injection of the grouting material is applied to the tension member 30 by applying a tensile force to the rock surface by loading the preceding load This is to support the load, and thus the grouting selectively injected into the drilling hole (h) is able to proceed with another excavation even if it is not firmly solidified.

The tension member 30 is gripped as shown in FIG. 4C through the wedge 64 inserted into the cone-shaped inner surface 62b of the fixing body 62 forming the anchorage 60 at the inlet side of the drilling hole h as above. In Figure 4d as shown in the fixing body 62, the mandrel hook 66 is inserted and the cap 68 is fastened to finish. As such, after the mandrel 66 and the cap 68 are assembled to the fixed body 62, the wedges 64 of the fixed body 62 are not separated and detached from the mandrel 66. It is possible to get the net to be covered.

Figure 5 is a view showing another embodiment of the portion mounted to the inlet of the drilling hole in the preloaded lock bolt device according to the present invention. Here, a packer 70 is provided between the end of the release hollow pipe 10 and the pressure plate 50 to support the end of the release hollow pipe 10 to block the inlet of the hole. The packer 70 and the pressure plate 50 are provided. ), Two grout inlets 54, 72 are formed to inject the grouting material into the drilling holes and remove foreign substances.

According to the configuration of another embodiment configured as described above, since the inlet portion of the drilling hole (h) is closely closed, the tension member (20) is fixed to the inner surface of the drilling hole (h) by the method as described above. 30) after applying the tensile force to the load, and then injecting the grout injecting cement mortar through the grout inlet (54, 72) of the packer 70 and the pressure plate 50, the grout inlet Furnace can be pressure grouting while removing the air or foreign matter in the hole (h). At this time, the curing is made in a state where the cement mortar is reliably penetrated between the rock of the discontinuous surface.

Thus, after the cement mortar, which is a grouting material, is cured, cement mortar penetrates and cures between the rocks of the discontinuous surface, thereby further strengthening the strength of the rock.

In addition to showing and explaining the preceding load-loaded lock bolt device of the present invention, various modifications can be made, unless the embodiments depart from the scope of the present invention, all the embodiments to be modified are included in the scope of the present invention for interpretation. Should be.

According to the preceding load-loaded lock bolt device according to the present invention as described above, by expanding the expansion tank to the outside while the cone-shaped body mounted on the end of the tension member is pulled out, that is, by extending the outer surface radially cylindrical of the same diameter The fixing force is improved more excellently because it is fixed to the inner surface of the drilled hole, and the safety of the slope is strengthened by the restraint effect on the discontinuous surface of the rock when the preceding load is applied to the tension member, so additional excavation work is performed immediately without curing period of the grouting material. This is expected to shorten the construction period.

In addition, when the packer is installed at the entrance of the hole in the loading stage of the preceding load, pressurizing grouting is performed while the ground is constrained, and after the grouting, the release hollow pipe exerts a lock bolt function to maximize the reinforcement effect of the ground. The effect is expected.

Claims (5)

A release hollow pipe 10 having irregularities formed on an outer surface thereof; The expansion tub 20 is installed to extend radially at one end of the release hollow pipe 10 and the tension member 21 and the cone-shaped inner surface 22 are formed in the center line direction and have an equal angle and are divided into two or more. ; A tension member 30 installed through the release hollow pipe 10 and the expansion tank 20; Cone-shaped body 40 is fastened and fixed to the end of the tension member 30 is inserted into the cone-shaped inner surface 22 of the expansion tank 20; A pressure plate 50 supporting the other end of the release hollow pipe 10 and having a tension member hole 52 through which the tension member 30 penetrates; It is installed at the end of the tensile member 30 drawn out through the release hollow pipe 10 and the pressure plate 50, characterized in that it is provided with a fixing device 60 for maintaining the tension member 30 in a tensioned state Preloaded lock bolt device. The method of claim 1, To ensure smooth expansion of the expansion tank 20, the flange 24 having a conformal and radially formed guide groove 24a is fixed to the end of the release hollow pipe 10 at a number equal to the number of divisions of the expansion tank 20, Guide pins 26 are fastened through the guide grooves 24a of the flanges 24 so that each of the expansion tanks 20 can move radially. The guide pins 26 and the guide grooves are attached to the flanges 24. A preload-loaded lock bolt device, characterized in that a flange cap 28 is covered to prevent foreign matter from penetrating into 24a and the like. The method of claim 1, Fixing the expansion tank such as bands, wires, etc. that can be cut by a predetermined expansion external force in the expansion tank without interrupting the operation when transporting or inserting the lock bolt device into a hole such as a rock or the like on the outer surface of the expansion tank 20 Ring loading device for the preceding load, characterized in that the ring 23 is further fastened. The method of claim 1, A packer 70 is provided between the end of the release hollow pipe 10 and the pressure plate 50 to block the entrance of the drilling hole while supporting the end of the release hollow pipe 10, and the packer 70 and the pressure plate 50 are provided at the end of the release hollow pipe 10. And a grout inlet (54) (82) for injecting grouting material into the punching hole and removing foreign substances. The method of claim 1, The fixing unit 60 is inserted into the fixing body 62 in which the tension material hole 62a and the cone-shaped inner surface 62b are formed, and the cone-shaped inner surface 62b of the fixing body 62 to fix the tension member 30. Pre-loaded lock bolt, characterized in that consisting of two or more wedges 64 and the cap 68 is fastened to the fixed body 62 to cover the end of the wedge 64 and the tension member 30 Device.

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