JP5270724B2 - Repair structure of existing cement mortar protective layer on slope - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a simple repair structure of an existing cement mortar protective layer of a slope face, which reliably prevents displacement of a repair layer without complicated operation. <P>SOLUTION: A repair structure of an existing cement mortar protective layer 2 which covers the slope face of a natural ground 1 includes: a bottomed groove 6 for preventing displacement arranged on the surface layer part of the existing cement mortar protective layer 2; and a repair layer 4 of reinforcement resin fiber-containing polymer cement mortar 4' which covers the surface of the existing cement mortar protective layer 2. The groove 6 for preventing displacement is filled with a portion of the reinforcement resin fiber-containing polymer cement mortar, so as to prevent the displacement of the repair layer. <P>COPYRIGHT: (C)2013,JPO&amp;INPIT

Description

  The present invention relates to a structure for repairing an existing cement mortar protective layer that has deteriorated over time and covers a natural slope.

  At the time of repairing the existing cement mortar protective layer that has cracked due to deterioration over time, there has been a widespread construction for repairing by forming a repair layer by spraying new mortar on the existing cement mortar protective layer. .

  The repair layer is formed thinner than the existing cement mortar protective layer. However, the repair layer becomes heavy when it covers a wide area, and the repair layer is displaced along the inclination of the existing cement mortar protective layer. The problem of falling will arise.

  Therefore, as a repair method for preventing the displacement of the repair layer as described above, a hole reaching the ground is drilled in the existing cement mortar protective layer, and the anchor pin is driven into the ground through the hole. A repair method for embedding the head in the repair layer to prevent misalignment has been implemented (see, for example, Patent Document 1).

JP 2005-36579 A

  Although it is possible to prevent displacement of the repair layer formed on the existing cement mortar protective layer by the repair method disclosed in Patent Document 1, this repair method is configured to prevent the pin point from being displaced by an anchor pin.

  Therefore, there is a problem that the anchor pin has to be driven at a high density in order to surely stop the displacement, and the work becomes complicated, and there is a problem that the displacement is partially lost at a place where the anchor pin does not act. is there.

  This invention provides the repair structure of the existing cement mortar protective layer which solves the said problem fundamentally.

  Specifically, forming a bottomed groove prevention groove in the surface layer portion of the existing cement mortar protective layer, covering the surface of the existing cement mortar protective layer with a polymer cement mortar containing reinforcing resin fibers, and forming a repair layer, Provided is a repair structure in which part of the polymer cement mortar containing the reinforcing resin fiber is filled in the misalignment prevention groove, and the repair layer is intended to prevent misalignment by the misalignment prevention groove.

  Further, a sealing material is injected into a crack generated in the existing cement mortar protective layer, and the shift preventing groove is formed so as to intersect with the crack into which the sealing material is injected.

  Preferably, the misalignment-preventing groove is disposed so as to intersect the lateral direction and the longitudinal direction so as to prevent misalignment in both the lateral direction and the longitudinal direction.

  Further, a headed anchor pin reaching the ground is erected in the groove for preventing misalignment, and the anchor pin is embedded in the polymer cement mortar containing the reinforcing resin fiber so as to strengthen the repair structure.

  According to the repair structure of the existing cement mortar protective layer having a slope according to the present invention, it is possible to surely prevent the repair layer from being displaced with a simple structure without complicated work.

Explanatory drawing which outlines the state in which the existing cement mortar protective layer which covers the slope has deteriorated over time and has cracked. Explanatory drawing which outlines the state which formed the groove | channel for the slip prevention extended in the horizontal direction in the surface layer part of the said existing cement mortar protective layer. Explanatory drawing which outlines the state which formed the groove | channel for slip prevention which cross | intersects a horizontal direction and a vertical direction in the surface layer part of the said existing cement mortar protective layer. A is an explanatory view outlining the cross section of the groove for preventing misalignment, and B is an explanatory view outlining an anchor pin standing in the groove for preventing misalignment. A is an explanatory view outlining a section of the groove for preventing misalignment after the polymer cement mortar containing reinforcing resin fibers is sprayed, and B is a groove for preventing misalignment where the anchor pins are erected after the polymer cement mortar containing reinforcing resin fibers are sprayed. Explanatory drawing which outlines a cross section.

  Hereinafter, embodiments of the present invention will be described with reference to FIGS.

  In the repair structure of the existing cement mortar protective layer having a slope according to the present invention, a crack 3 due to aging has occurred in the existing cement mortar protective layer 2 covering and protecting the slope of the natural ground 1 as shown in FIG. In this case, the repair layer 4 is newly formed on the existing cement mortar protective layer 2 and applied to repair for regenerating the existing cement mortar protective layer 2.

  In the repair, first, high pressure water is sprayed onto the surface of the existing cement mortar protective layer 2 to clean the surface, and the cement mortar that has deteriorated and becomes brittle is removed.

  Next, after marking the crack 3, the sealing material 5 is filled in the crack 3. Alternatively, the width of the crack 3 is expanded and the sealing material 5 is filled in the expanded crack 3.

  Next, as shown in FIG. 2 or FIG. 3, bottomed misalignment grooves 6 are formed in the surface layer portion of the existing cement mortar protective layer 2.

  That is, as shown in FIG. 2, a groove for preventing misalignment extends in the lateral direction (substantially horizontal direction with respect to GL) with respect to the existing cement mortar protective layer 2 with a cutting machine or the like on the surface layer portion of the existing cement mortar protective layer 2 A plurality of 6 are formed. For example, when the thickness of the existing cement mortar protective layer 2 is 50 to 150 mm, the width and depth of the misalignment stopping groove 6 are preferably 20 to 30 mm in width and 20 to 30 mm in depth.

  Alternatively, as shown in FIG. 3, in addition to the groove for preventing misalignment 6 extending in the lateral direction with respect to the existing cement mortar protective layer 2 in the surface layer portion of the existing cement mortar protective layer 2, the longitudinal direction (existing cement mortar The groove for preventing misalignment 6 extending in the inclination direction of the protective layer 2 is formed, and the groove for preventing misalignment 6 is disposed so as to intersect the horizontal direction and the vertical direction. It is preferable to arrange the misalignment prevention groove 6 so that the surface area defined by the misalignment prevention groove 6 intersecting the horizontal direction and the longitudinal direction is a square having one side of 1 to 2 m.

  As shown in FIG. 4A, the groove for preventing misalignment 6 is formed in a U-shaped cross section having a bottom portion 6a and an inner wall portion 6b rising from the bottom portion 6a. Alternatively, it is not excluded to form the bottom portion 6a of the misalignment stopping groove 6 so as to have a cross-sectional arc shape and to form the misalignment stopping groove 6 into a U-shaped cross section.

  Accordingly, the inner wall portion 6b of the groove for preventing misalignment 6 extending in the lateral direction is formed so as to extend in a direction intersecting the inclination direction of the existing cement mortar protective layer 2, and the inner wall portion of the groove for preventing misalignment 6 extending in the vertical direction. 6b is formed so as to extend in the inclination direction of the existing cement mortar protective layer 2, and both inner wall portions 6b and engaging portions 4b of a repair layer 4 to be described later are securely engaged to prevent the repair layer 4 from slipping. .

  Both the laterally and longitudinally extending misalignment grooves 6 are formed so as to intersect with the crack 3 into which the sealing material 5 has been injected. In other words, the above-described misalignment groove 6 is formed without being caught in the extending direction of the crack 3, thereby ensuring reliable misalignment of the repair layer 4 described later.

  As shown in FIG. 4B, when the anchor pin 7 reaching the natural ground 1 is erected, a through-hole 8 reaching the natural ground 1 is drilled at the bottom 6a of the misalignment stopping groove 6 with a drill or the like, The anchor pin 7 is driven into the natural ground 1 through the through hole 8 and the anchor pin 7 is erected. At this time, the anchor pin 7 is erected with its head portion 7a protruding outward from the misalignment groove 6.

  Next, as shown in FIG. 5A, the polymer cement mortar 4 ′ containing reinforcing resin fibers is sprayed on the surface of the existing cement mortar protective layer 2 to form the repair layer 4, thereby completing the repair structure according to the present invention. The repair layer 4 has a structure excellent in toughness and tensile strength due to the reinforcing resin fibers 9 contained in the polymer cement mortar 4 'containing reinforcing resin fibers.

  Part of the polymer cement mortar 4 ′ with reinforcing resin fibers is filled in the groove 6 for preventing misalignment, and the filled polymer cement mortar 4 ′ with reinforcing resin fibers has an internal shape (bottom portion 6 a). And hardening according to the inner wall 6b).

  Therefore, the repair layer 4 forms a cover 4a that covers the existing cement mortar protective layer 2 and an engaging portion 4b that engages with the groove 6 for preventing misalignment. The existing cement mortar protective layer 2 is covered to prevent deterioration of the existing cement mortar protective layer 2 and rainwater intrusion, thereby regenerating the existing cement mortar protective layer 2. The thickness of the cover 4a of the repair layer 4 is preferably 2 to 5 mm when the thickness of the existing cement mortar protective layer 2 is 50 to 150 mm, for example.

  More specifically, the cover 4a of the repair layer 4 covers the surface of the existing cement mortar protective layer 2 to prevent further deterioration of the existing cement mortar protective layer 2 and to prevent rainwater from entering. Further, the engaging portion 4b of the repair layer 4 is engaged with both the laterally and longitudinally extending misalignment grooves 6 so that the longitudinal displacement of the repair layer 4, that is, the inclination of the existing cement mortar protective layer 2 is inclined. Both the displacement along the surface and the lateral displacement of the repair layer 4, that is, the displacement substantially in the horizontal direction with respect to the GL are surely prevented.

  Further, the sealing material 5 injected into the crack 3 and hardened forms a recess 5 a on the surface side of the existing cement mortar protective layer 2. A part of the polymer cement mortar 4 ′ containing the reinforcing resin fibers is also filled in the recess 5 a of the sealing material 5, thereby further improving the effect of preventing the repair layer 4 from slipping.

  As shown in FIG. 5B, when the anchor pin 7 reaching the natural ground 1 is erected, the head portion 7a of the anchor pin 7 is embedded in a polymer cement mortar 4 ′ containing reinforcing resin fibers, The anchor pin 7 is integrated to further improve the displacement prevention effect.

  In particular, the reinforcing resin fibers 9 in the polymer cement mortar 4 ′ containing the reinforcing resin fibers are intertwined with the head 7 a of the anchor pin 7 and contribute to the reliable integration of the repair layer 4 and the anchor pin 7. It becomes.

Finally, a preferable blending ratio of the above-mentioned polymer cement mortar 4 ′ containing reinforcing resin fibers will be described. The above-mentioned polymer cement mortar 4 ′ containing reinforcing resin fibers is blended at the following blending ratio to form the repair layer 4 having excellent toughness and tensile strength and watertightness.

<Blend ratio per cubic meter of polymer cement mortar 4 'with reinforcing resin fibers>
Portland cement 300-900kg (preferably 512kg)
Sand 300-900kg (preferably 471kg)
Polymer resin 30-300 kg (preferably 81 kg)
250-450 kg of water (preferably 351 kg)
Reinforced resin fiber 10-40kg (preferably 15.5kg)
Others (calcium carbonate, silica fume, etc.) 50-300kg

  As the reinforcing resin fiber 9, a vinylon fiber having a fiber length of 3 to 18 mm and a thickness of 10 to 45 μm, the same polyethylene fiber, or a mixed fiber of the same vinylon fiber and the same polyethylene fiber is effective.

  When a mixed fiber of vinylon fiber and polyethylene fiber is used as the reinforcing resin fiber 9, it is selected from 5 to 35 kg of vinylon fiber and 5 to 35 kg of polyethylene fiber, and blended so as to be 10 to 40 kg as a whole.

  As the polymer resin, a styrene butadiene resin system, a polyacrylic ester resin system (acrylic resin system), an ethylene vinyl acetate resin system, a vinyl acetate / veova resin system, or the like is used. It is desirable that the polymer resin is mixed with water after being diluted about twice.

  As said sand, the simple substance or mixture, such as quartz sand manufactured from quartzite, artificial lightweight sand (for example, ceramic sand), river sand, mountain sand, ore, fly ash, is mix | blended.

  As described above, the numerical range indicated by “˜” between the lower limit value and the upper limit value represents all the numerical values (integer value and decimal value) between the lower limit value and the upper limit value.

  DESCRIPTION OF SYMBOLS 1 ... Ground mountain, 2 ... Existing cement mortar protective layer, 3 ... Crack, 4 ... Repair layer, 4 '... Polymer cement mortar containing a reinforced resin fiber, 4a ... Cover part, 4b ... Engagement part, 5 ... Sealing material, 6 Deflection stop groove, 6a ... bottom, 6b ... inner wall, 7 ... anchor pin, 7a ... head, 8 ... through hole, 9 ... reinforced resin fiber.

Claims (4)

  It is a repair structure of an existing cement mortar protective layer that covers the slope of a natural ground, and a bottomed groove is formed in the surface layer portion of the existing cement mortar protective layer to reinforce the surface of the existing cement mortar protective layer Covering with resin fiber-containing polymer cement mortar to form a repair layer, filling part of the reinforcing resin fiber-containing polymer cement mortar into the misalignment prevention groove, and preventing the misalignment of the repair layer with the misalignment prevention groove A structure for repairing a protective layer of an existing cement mortar with a slope, characterized in that it is configured to achieve.   The slope according to claim 1, wherein a sealing material is injected into a crack generated in an existing cement mortar protective layer, and the groove for preventing misalignment is formed so as to intersect with the crack into which the sealing material is injected. Repair structure of existing cement mortar protective layer.   The repair structure of the existing cement mortar protective layer on a slope according to claim 1 or 2, wherein the groove for preventing misalignment is arranged so as to intersect the horizontal direction and the vertical direction.   4. A headed anchor pin reaching the ground is erected in the misalignment stop groove, and the anchor pin is embedded in the polymer cement mortar containing the reinforcing resin fiber. The repair structure of the existing cement mortar protective layer of the slope in any one of.