JP2007308893A - Repair structure of concrete - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a repair structure of concrete capable of draining the water oozing out into an anchor pin insertion hole of a concrete skeleton. <P>SOLUTION: A reinforced fiber sheet 1 is attached to a surface of the concrete skeleton 4 by an anchor pin 2, and resin is impregnated into the reinforced fiber sheet 1 and is solidified. The anchor pin 2 is provided with a large diameter part 2b and a tapered part 2g at one end of a cylindrical main body part 2a and forms a slit 2c extending in the axial direction while leaving a part in the vicinity of it in the main body part 2a. When attaching the reinforced fiber sheet 1, a taper pin 2e is pushed into a tip part of the anchor pin 2, which is opened and enlarged and is brought into pressure-contact with a peripheral face of a hole 5 in the concrete skeleton 4, and the reinforced fiber sheet 1 is pressed against the surface of the concrete skeleton 4 by a locking part 2b. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a concrete repair structure.

  When a crack is generated on the wall surface of the tunnel, a fiber reinforced plastic (FRP) containing an aramid fiber or carbon fiber is attached to the cracked portion for repair. That is, after a reinforcing fiber sheet is attached to the surface of a concrete frame, a resin is applied thereon, and this is impregnated into the reinforcing fiber sheet to form a fiber-reinforced plastic layer (Patent Document 1).

FIG. 10 shows an example of a reinforcing fiber sheet mounting structure. That is, the anchor pin 21 is planted in the concrete frame 20, and the nut 22 is screwed to the screw portion 20a to fix the reinforcing fiber sheet 23. A hollow portion 20c and a slit 20d are formed in the main body portion 20b of the anchor pin 20, and a taper pin 20e is attached to the hollow portion 20c. Then, the anchor pin 21 is inserted into the hole 26 of the concrete housing 20, the end of the screw portion 20a is hit with a hammer, the taper pin 20e is pushed into the hollow portion 20c, the hollow portion 20c is expanded, and the peripheral surface of the hole 26 is expanded. It is in pressure contact.
JP-A-3-224901

  However, in this structure, groundwater or the like oozes out into the hole 26 through the concrete housing 20, and the water accumulated in the hole 26 enters the gap between the concrete housing 20 and the fiber reinforced plastic, thereby peeling the fiber reinforced plastic. There is.

  In view of such circumstances, an object of the present invention is to provide a concrete repair structure capable of discharging water that has oozed into an anchor pin insertion hole of a concrete frame.

  In order to solve the above problems, the present invention provides a structure in which a reinforcing fiber sheet is attached to the surface of a concrete frame with an anchor pin, and the reinforcing fiber sheet is impregnated with a resin and solidified. An anchoring means is provided at one end of the main body, and a slit extending in the axial direction is formed in the main body while leaving the vicinity of the locking means. When attaching the reinforcing fiber sheet, the taper pin is pushed into the tip of the anchor pin, and the anchor pin And the reinforcing fiber sheet is pressed against the surface of the concrete frame with a flange.

  It is preferable to form a drainage hole in a portion of the anchor pin body portion that is inserted into the hole of the concrete frame.

  It is preferable to arrange the drain holes on both sides of the slit.

  According to the present invention, even if water oozes out into the anchor pin insertion hole of the concrete frame, the oozed water enters the inside through the slit of the anchor pin, passes through the inside of the anchor pin, Since it is discharged from the opening to the outside, it is difficult for water to enter the gap between the concrete frame and the fiber reinforced plastic, which helps prevent the fiber reinforced plastic from peeling off.

Embodiments of the present invention will be described below in detail with reference to the accompanying drawings.
FIG. 8 is a diagram showing a repaired portion of the tunnel wall surface S, and the fiber reinforced plastic P is pasted and repaired at the cracked portion. In the repair, first, the reinforcing fiber sheet 1 made of aramid fiber is attached to the tunnel wall surface S with the anchor pin 2 (see FIG. 7). The reinforcing fiber sheet 1 is cut into a predetermined width (usually 1 m), and the side edge portion is overlapped with the side edge portion of the adjacent reinforcing fiber sheet 1, and the pressing plate 3 made of fiber reinforced plastic is formed thereon. These are fixed to the concrete frame 4 with the anchor pins 2 (see FIG. 6). The pressing plate 3 contains an aramid fiber as a reinforcing fiber and is made of the same matrix resin as the fiber-reinforced plastic P that repairs the tunnel wall surface S.

  FIG. 1 is an enlarged view showing a placement portion of the anchor pin 2 in FIG. 6, FIG. 2 is a perspective view of the anchor pin 2, and FIG.

  The anchor pin 2 expands one end of the cylindrical main body 2a to form a large-diameter portion 2b and a tapered portion 2g (locking means), and extends in the axial direction leaving the vicinity of these portions 2b and 2g. A slit 2c is formed in the main body 2a. Further, a flange portion 2d is formed at the tip portion and the central portion of the main body portion 2a. A taper pin 2e is accommodated in the main body 2a.

  When attaching the reinforcing fiber sheet 1, first, the reinforcing fiber sheet 1 and the pressing plate 3 are put on the surface of the concrete housing 4, and these are inserted into the holes 5 of the concrete housing 4 through the anchor pins 2. A washer 6 is attached to the anchor pin 2 in advance. Next, a push rod (not shown) is passed through the anchor pin 2 and the end thereof is struck with a hammer to push the taper pin 2e into the distal end side of the main body 2a. Press contact with the peripheral surface. Then, the large diameter portion 2 b and the tapered portion 2 g press the reinforcing fiber sheet 1 against the surface of the concrete housing 4 via the washer 6 and the pressing plate 3, and the reinforcing fiber sheet 1 is fixed to the concrete housing 4.

  By the way, an undercoat resin is applied to the surface of the concrete housing 4 prior to the attachment of the reinforcing fiber sheet 1. Further, after the reinforcing fiber sheet 1 is attached to the surface of the concrete casing 4, an overcoat resin is applied thereon, and this is impregnated into the reinforcing fiber sheet 1 to form a fiber reinforced plastic P. Finally, an acrylic urethane resin is used. Apply finish paint.

  By the way, the reinforcing fiber sheet 1 is disposed so as to cover a concrete peeling expected range Z as shown in FIG. In that case, in order to make the attachment strength of the reinforcing fiber sheet 1 sufficient, it is necessary to secure a sufficient fixing length L around the expected peeling range Z. The fixing length L is usually set to 50 cm. However, when there is an installation object M such as a fluorescent lamp in the vicinity of the concrete peeling expected range Z, it is difficult to secure a sufficient fixing length. In that case, a pressing plate 3A made of fiber reinforced plastic may be installed between the installation object M and the expected peeling range Z to secure the mounting strength of the reinforcing fiber sheet 1.

  According to the structure of this embodiment, even if water oozes out into the hole 5 of the concrete housing 4, the oozed water enters the anchor pin 2 through the slit 2 c and passes through the anchor pin 2. It is discharged to the outside through the opening 2h on the locking portion 2b side. For this reason, it becomes difficult for water to enter the gap between the concrete housing 4 and the fiber reinforced plastic P, which helps to prevent the fiber reinforced plastic P from peeling off.

  By the way, in order to improve drainage from the anchor pin 2, it is only necessary to form a drainage hole 2f in the main body 2a as shown in FIGS. Further, if the drain holes 2f are arranged on both sides of the slit 2c, it is possible to further improve the drainability while maintaining the strength necessary for the anchor pin 2.

  Further, in the present embodiment, the reinforcing fiber sheet 1 is cut to a predetermined width, the reinforcing fiber sheets 1 are arranged side by side to cover the concrete peeling expected range Z, and the side edges of the reinforcing fiber sheets 1 are arranged. Overlaid and fixed to the concrete frame 4 with anchor pins 2. For this reason, even if the concrete exfoliation range Z is large, it is not necessary to attach the large reinforcing fiber sheet 1 at a time, and the construction becomes easy. Moreover, since the reinforcing fiber sheet 1 is pressed by the pressing plate 3 made of the same material, the familiarity is good and it is useful for preventing the reinforcing fiber sheet 1 from being broken.

  In the above embodiment, one end of the cylindrical main body portion 2a is enlarged to form the large diameter portion 2b and the tapered portion 2g. However, the locking means is not limited to this, and the main body A flange provided at one end of the portion 2a may be used, or a male screw may be formed at one end of the main body portion 2a and a nut may be screwed.

It is sectional drawing which shows the repair structure of the concrete of this invention, and is the figure which expands and shows the placement part of the anchor pin of FIG. The perspective view of the anchor pin used with the repair structure. The front view which fractures | ruptures and shows a part of the anchor pin. The figure which shows the modification of FIG. The figure which shows the modification of FIG. Sectional drawing which shows the attachment structure of a reinforced fiber sheet. The top view which shows the attachment state of a reinforced fiber sheet. The figure explaining the repair method of a tunnel wall surface. The figure explaining the fixing length of a reinforced fiber sheet. The figure which shows the prior art example corresponding to FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Reinforcing fiber sheet 2 Anchor pin 2a Main body part 2b Large diameter part 2d Gutter part 2e Taper pin 2f Drain hole 2g Taper part 3 Pressing plate 4 Concrete frame 5 Hole

Claims (3)

  In a structure in which a reinforcing fiber sheet is attached to the surface of a concrete frame with an anchor pin and the reinforcing fiber sheet is impregnated with a resin and solidified, the anchor pin includes a locking means at one end of a cylindrical main body, and the engagement pin A slit that extends in the axial direction leaving the vicinity of the stopping means is formed in the main body, and when attaching the reinforcing fiber sheet, the taper pin is pushed into the tip of the anchor pin, and the anchor pin is expanded to open the peripheral surface of the concrete frame A concrete repair structure characterized in that the reinforcing fiber sheet is pressed against the surface of the concrete frame at the locking portion while being pressed against the surface.   2. The concrete repair structure according to claim 1, wherein a drainage hole is formed in a portion of the anchor pin body portion inserted into the hole of the concrete frame. 3. The concrete repair structure according to claim 2, wherein drain holes are arranged on both sides of the slit.

Images