JP3486029B2 - Synthetic resin anchor bolt - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an excavated wall, which is buried in a ground around a wall excavated in tunnel construction or a slope of a ground. The present invention relates to a synthetic resin anchor bolt for preventing a slope from collapsing. 2. Description of the Related Art In tunnel construction, for example, in order to prevent exfoliation or collapse of the ground from an excavated wall surface, a hole having an appropriate depth is formed from the excavated wall surface in the surrounding ground. An anchor bolt is inserted into the hole, and a hardening material such as mortar is filled into the hole to fix the anchor bolt, and the ground is reinforced by fixing the base end of the anchor bolt protruding from the excavation wall surface to the wall surface. That is being done. As such an anchor bolt, a synthetic resin anchor bolt made of FRP, which is lightweight, has high tensile strength and can be easily cut to a desired length, is used instead of a steel bolt. When such a synthetic resin anchor bolt is fixed to a digging wall as described above, a base 22 of an anchor bolt 21 protruding from the digging wall is conventionally interposed via a plate 22 as shown in FIG. After the ring body 23 is fitted, the wedge 24 is driven from the base end face of the anchor bolt 21 to expand the base end, thereby expanding the tapered surface.
25 is pressed against the inner peripheral surface of the ring body 23 or, as shown in FIG. Epoxy resin adhesive 27 in the gap between the tube 26 and the anchor bolt 21
The steel screw cylinder 26 is fixed to the base end of the anchor bolt 21 by filling and solidifying
After the anchor bolt 21 is inserted into the hole 28 formed in the surrounding ground from the excavated wall surface as described above in a state where the plate 22 is slidably fitted to the plate 22 and fixed with a hardening material 29 such as mortar, The fixing is performed by screwing a nut 30 into the steel screw cylinder 26 and pressing it against the plate 22. [0004] However, according to the former anchor bolt fixing means, when the anchor bolt 21 is tensioned, the pressure contact surface between the anchor bolt 21 and the wedge 24 or the pressure contact surface between the ring body 23 and the ring member 23 is formed. There is a possibility that slippage may occur, and according to the latter anchor bolt fixing means, the adhesive force between the anchor bolt and the steel screw cylinder 26 is small, so that a strong fixing force cannot be exerted, and the anchor bolt is large. There was a problem that the pullout strength could not be expected. An object of the present invention is to provide a synthetic resin anchor bolt that can fundamentally solve such problems. In order to achieve the above object, a synthetic resin anchor bolt according to the present invention comprises a base end portion of a synthetic resin anchor bolt body having a spiral ridge formed on a surface thereof. And spiral grooves are engraved on the inner and outer peripheral surfaces
Screw groove for screwing a steel nut into the spiral groove provided on the side
Formed covered a steel cylindrical cap body formed in, by filling an epoxy resin adhesive is mixed with aluminum powder in the gap portion between the cap member and the base end portion peripheral surface of the anchor bolt body said The steel tubular cap body is integrally fixed to the anchor bolt body with an epoxy resin adhesive, and a pin is passed through the base end of the anchor bolt body in the steel tubular cap body in the diameter direction of the anchor bolt body. In addition, both ends of the pin are locked in locking holes provided on both side surfaces of the steel tubular cap body. DESCRIPTION OF THE PREFERRED EMBODIMENTS An anchor bolt body is made of fiber reinforced resin (FRP) and has a spiral ridge formed on the surface thereof. A tubular cap made of steel is placed on the base end of the anchor bolt body, and a gap between the cap body and the peripheral surface of the base end of the anchor bolt body is filled with an epoxy resin adhesive. The body is fixed to the anchor bolt body. At that time, the epoxy resin adhesive bites into the spiral groove between the spiral ridges provided on the surface of the anchor bolt main body and the spiral groove provided on the inner peripheral surface of the cylindrical cap body in a state of biting, thereby providing an anchor effect. In addition, the solid of aluminum powder mixed in the epoxy resin adhesive can prevent the adhesive from shrinking and increase the hardness when cured. Further, a pin is diametrically penetrated through the base end of the anchor bolt main body, and both ends of the pin are locked in locking holes provided on both side surfaces of the cylindrical cap body. Combined with the strong adhesive action of the above-mentioned epoxy adhesive mixed with aluminum powder on the surface spiral ridge of the bolt body and the inner spiral groove of the cylindrical cap body, the pull-out resistance of the cylindrical cap body with respect to the anchor bolt body is extremely increased. Is what it is. In addition, when the anchor bolt body is inserted into a hole formed in an excavation wall or the like and filled with a hardening material such as mortar, a spiral ridge formed on the surface of the anchor bolt increases pulling resistance and increases resistance to the ground. Strong fixing is possible, and stable ground reinforcement can be performed. An embodiment of the present invention will be described with reference to the drawings.
Reference numeral 1 denotes an anchor bolt body made of FRP (fiber reinforced resin), and a spiral ridge 2 is formed on the entire surface of the anchor bolt. In order to obtain such an anchor bolt body 1, for example, an uncured unsaturated polyester resin, an epoxy resin, or the like is applied to a strand made of a fiber bundle of high strength and low elongation such as glass fiber, carbon fiber, or aromatic polyamide fiber. Impregnated with a thermosetting resin, and a plurality of the resin-impregnated strands,
It can be manufactured by twisting and forming into a single rope body, heating it to cure the thermosetting resin, and then cutting the rope body at regular lengths (several meters). The spiral ridge 2 is formed by the twisted strands, and the adjacent spiral ridges 2, 2 are formed.
It has a structure in which a spiral groove 2a is provided between them. A pin insertion hole 3 that penetrates in a diametrical direction at a portion at a small distance from the base end surface is formed in a base end portion of the anchor bolt main body 1. In addition, the anchor bolt body 1 is formed by several tens to
After immersing 100 glass fibers in a curable resin, it is drawn into a circular mold, molded, and squeezed with a high-strength thread that has been tensioned before the resin is cured. Irregularities may be formed. Reference numeral 4 denotes a steel cylindrical cap body having a diameter larger than that of the synthetic resin anchor bolt body 1, and one end opening side is closed by a top plate 4a. Spiral grooves 5 and 6 are engraved on the inner and outer peripheral surfaces of the cap body 4 over the entire length, and are diametrically opposed to an intermediate portion at a certain interval in the length direction from the inner surface of the top plate 4a. Pin locking holes 7 and 8 are formed on both side surfaces so as to correspond to the pin insertion holes 3 provided at the base end of the anchor bolt body 1. In the spiral grooves 5 and 6 provided on the inner and outer peripheral surfaces of the cap body 4, the spiral grooves 5 on the outer peripheral surface are formed as screw grooves into which a steel nut 9 can be screwed. The cap body 4 is the anchor bolt body 1
The two ends of the pin 10 fitted in the base end of the cap bolt 4 and inserted through the pin insertion hole 3 provided in the base end of the anchor bolt body 1 are locked in the locking holes 7, 8 on both sides of the cap body 4. At the same time, both are fixed together by an aluminum powder-mixed epoxy resin adhesive 11 filled in a gap between the base end surface of the anchor bolt body 1 and the inner peripheral surface of the cap body 4 to form an anchor bolt. I have. To attach the cap body 4 to the base end of the anchor bolt main body 1, first, as shown in FIG. 2, the cap body 4 is put on the base end of the anchor bolt main body 1. At this time, when the inner surface of the top plate 4 a of the cap body 4 is brought into contact with the base end surface of the anchor bolt body 1, the pin insertion holes 3 provided in the anchor bolt body 1 are provided on both sides of the cap body 4. It matches the stop holes 7 and 8 in communication. In this state, the pin 10 is inserted through the pin insertion hole 3 provided in the anchor bolt main body 1 from the one pin engagement hole 7 of the cap body 4 and the pin 10 is inserted between the other pin engagement holes 8. As shown in FIG. 3, both ends of the pin 10 are locked in the locking holes 7, 8 on both sides of the cap body 4. Thereafter, as shown in FIG. 4, the gap between the outer peripheral surface of the anchor bolt main body 1 and the inner peripheral surface of the cap body 4 is filled with an epoxy resin adhesive 11 mixed with aluminum powder and solidified. The cap body 4 is integrally fixed to the anchor bolt body 1. At this time, the aluminum powder mixed into the epoxy resin adhesive 11 prevents the adhesive 11 from shrinking and increases the hardness when hardened.
And the epoxy resin adhesive 11 firmly bites into the spiral groove 2a between the spiral ridges 2 and 2 of the anchor bolt main body 1 and the spiral groove 6 provided on the inner peripheral surface of the cap body 4. Thus, an anchor effect can be obtained, and an anchor bolt with extremely high pull-out resistance of the cap body 4 can be obtained together with the fixing by the pin 10. In order to strengthen the ground such as the ground of the tunnel excavation wall surface or the slope of the ground with the anchor bolts configured as described above, first, the ground is attached to the ground by using a drilling tool such as a drifter. A large diameter hole 12 is drilled. The anchor bolt main body 1 is inserted into the hole 12 from the tip end side, and the base end thereof is made to protrude from the ground surface, and a mortar or epoxy resin is inserted into a gap between the anchor bolt main body 1 and the hole 12. By injecting and filling a curable material 13 such as the like, and curing the curable material 13, as shown in FIG.
Is fixed via the curable material 13. The filling of the hardening material 13 into the hole 12 may be performed after the anchor bolt main body 1 is inserted into the hole 12. It is easier to insert in the work. In this way, the anchor bolt body 1 inserted into the hole 12 with the curable material 13 is fixed to the ground, and the steel nut 9 is screwed into the outer thread groove 5 of the cap body 4 projecting from the ground surface. The center hole of the anchor bolt body 1
A metal plate 14 in the shape of a washer through which the base plate 15 is inserted is pressed against the ground surface to reinforce the ground such as preventing the collapse of the ground. As described above, when the anchor bolt main body 1 is fixed to the ground, the pressing force due to the loosening of the ground acts on the cap body 4 via the plate 14 that holds down the ground surface. Acts on the anchor bolt main body 1 as a tensile force in the axial center direction, but the anchor bolt main body 1 locks the spiral ridge 2 on the surface thereof into the hole 12 and locks it with the hardened material 13 which is solidified. At the same time, the fixing force is firmly fixed in the hole 12 with a strong pull-out resistance due to the adhesive force of the curable material 13 together with the locking force. On the other hand, a fixing portion on the ground surface side, that is, a plate
A pull-out force due to the pressing force from the ground side also acts on the cap body 4 which presses the cap 14 to the ground surface via the nut 9, but the cap body 4 is integrally fixed to the anchor bolt body 1 by the pin 10. At the same time, the spiral ridge 2 of the anchor bolt main body 1 and the spiral groove 6 provided on the inner peripheral surface of the cap body 4 are engaged with the epoxy resin adhesive 11 in a biting state, and Strong pull-out resistance is exerted by the adhesive force of the epoxy resin adhesive 11 together with the force, and the ground can be firmly pressed down. As described above, according to the synthetic resin anchor bolt of the present invention, the spiral ridge is formed on the surface of the anchor bolt body over the entire length. It has a stopping effect and can be firmly fixed to the ground. Furthermore, since a spiral groove is provided on the inner peripheral surface of the cap body fitted on the base end of the anchor bolt main body,
The epoxy resin adhesive filled between the anchor bolt body and the cap body is engaged in the spiral groove of the cap body in a biting state, and the spiral ridge of the anchor bolt body is also engaged with the epoxy resin adhesive. As a result, the pull-out resistance of the anchor bolt body and the cap body to the epoxy resin adhesive becomes extremely large, and the anchor bolt body and the cap body can be firmly integrated. Further, since aluminum powder is mixed in the epoxy resin adhesive, the shrinkage preventing action of the aluminum powder and the action of increasing the hardness after hardening are used to lock the epoxy resin adhesive with the anchor bolt body and the cap body. Strength and strength can be further increased, and a pin is diametrically penetrated through the base end of the anchor bolt body, and both ends of the pin are locked in locking holes provided on both side surfaces of the cylindrical cap body. Because of the strong adhesive action of the epoxy adhesive mixed with the aluminum powder on the surface spiral protrusion of the anchor bolt body and the inner spiral groove of the cylindrical cap body, the pull-out resistance of the cylindrical cap body with respect to the anchor bolt body is reduced. It is extremely increased and has a remarkable action and effect as a reinforcing anchor bolt for preventing the collapse of the ground.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a side view in which a part of an anchor bolt is cross-sectioned; FIG. 2 is a longitudinal side view in a state where a cap body is fitted on an anchor bolt main body; FIG. 4 is a vertical sectional side view showing a state where a cap body is fixed to a bolt body, FIG. 4 is a horizontal sectional view showing a state where the cap body is integrated with an epoxy resin adhesive, and FIG. FIG. 6 is a vertical sectional side view showing a conventional anchor bolt fixing structure, and FIG. 7 is a vertical sectional side view showing another conventional anchor bolt fixing structure. [Description of Signs] 1 Anchor bolt body 2 made of synthetic resin 2 Spiral ridge 4 Cap body 5, 6 Spiral groove 7, 8 Pin locking hole 9 Steel nut 10 Pin 11 Epoxy resin adhesive mixed with aluminum powder

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Junji Kobayashi 1-1-3 Uchisaiwaicho, Chiyoda-ku, Tokyo Tokyo Electric Power Company (72) Inventor Kazuhisa Yoshizawa 1-1-3 Uchisaiwaicho, Chiyoda-ku, Tokyo Tokyo Electricity Co., Ltd. (72) Inventor Toru Furukawa 2-2-2 Matsuzakicho, Abeno-ku, Osaka-shi In Okumura Gumi Co., Ltd. (72) Inventor Akira Koga 2-2-2 Matsuzakicho, Abeno-ku, Osaka-shi Okumura Gumi Co., Ltd. (72) Inventor Toru Hama 3-2-17 Nishitenma, Kita-ku, Osaka-shi KK Corporation (56) References JP-A-62-182400 (JP, A) JP-A-3-41181 (JP) , A) JP-B-57-18484 (JP, B2) (58) Fields investigated (Int. Cl. ⁷ , DB name) E21D 20/00

Claims (1)

(57) [Claims 1] A spiral groove is formed on the inner and outer peripheral surfaces of a synthetic resin anchor bolt main body having a spiral ridge formed on its surface. The spiral groove provided on the surface side is made of steel
An epoxy resin in which a steel tubular cap formed in a screw groove for screwing a nut is covered, and aluminum powder is mixed in a gap between the cap and a base end peripheral surface of the anchor bolt body. An adhesive is filled, and the steel tubular cap body is integrally fixed to the anchor bolt main body with the epoxy resin adhesive, and the anchor bolt main body is attached to the base end of the anchor bolt main body in the steel tubular cap body. A synthetic resin anchor bolt characterized in that a pin is penetrated in a diametrical direction, and both ends of the pin are locked in locking holes provided on both side surfaces of the steel tubular cap body.