JP2000310042A - Repairing method of concrete retaining wall - Google Patents

Abstract

PROBLEM TO BE SOLVED: To heighten hardness and to improve abrasion resistance by holding surface material in front of a recessed part generated by erosion, breakage, fallout, falling in of the surface part of a concrete retaining wall, filling filler in the gap between the recessed part and the surface material to fix the surface material to the retaining wall. SOLUTION: Surface material 1 is formed so that a surface resin layer 3 is fixedly fitted to a concrete main body 2, a groove part 4 is on the left side, a linear projection 5 on the right side, respectively provided so as to engage with each other. In repairing, the surface material 1 is held with anchor reinforcements 8 in front of a recessed part 7, and reinforcements 9 are provided in the gap. Thereafter, on the surface contacted with concrete, polysulfide- modified epoxy resin is applied, and before hardening, ready mixed concrete is placed. By the polysulfide-modified epoxy resin, the ready mixed concrete is firmly fixed to the retaining wall and the surface material. After hardening, the projecting parts of the anchor reinforcements 8 are cut off. Hereby, a formwork itself is unnecessary, and concrete and ready mixed concrete are firmly stuck to each other.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for repairing a concrete retaining wall.

[0002]

2. Description of the Related Art Concrete retaining walls are frequently used for protecting steep slopes, rivers and coastal quays, cliffs and the like. These are intended to prevent the collapse and erosion of the sloping ground and the mountain surface, and to cast and solidify concrete, thereby stopping the concrete. In mountains, etc., it stabilizes the slope and protects the houses and roads above and below it, and prevents erosion by waves and gravel on river banks and beaches,
It not only protects the function and landscape of the port, but also has significant implications for national land conservation.

[0003] A concrete retaining wall is usually manufactured by assembling a formwork at the site and casting concrete. Of course,
There is also a method of installing already molded concrete.

[0004]

However, even if it is made of concrete and is durable, the seaside one is always subjected to impact and friction by its waves, sand, gravel and the like. In addition, in the case of a mountain or the like, not only a very large bending stress is applied due to the application of earth pressure, but also there are rocks falling from above. Therefore, due to erosion, breakage, falling off, collapse, etc., the concrete retaining wall has a concave portion (a concave portion in a large meaning, forming a concave portion together with the soil below, and a case of cracks, etc.). All included), that is, a defect may occur.

If such a concave portion is left as it is, erosion proceeds at a stretch on the beach, and if the retaining wall collapses, the surrounding roads and houses are seriously damaged. Further, in a mountain or the like, a collapse may occur at a stretch from there. Either way, it is very dangerous and must be repaired as soon as possible.

However, when repairing such a concave portion,
Simply reconstructing concrete is the same thing, and there is no doubt that recesses will occur again.

[0007]

Accordingly, the present inventor has completed the repair method of the present invention as a result of intensive studies, and is characterized by erosion and damage to the surface of the concrete retaining wall. A surface material is held at a predetermined interval in front of a concave portion caused by falling off, falling down, etc., a filler is filled in a gap between the concave portion and the surface material, and the surface material is made of concrete through the filler. A method for repairing a concrete retaining wall fixed to a wall, wherein the surface material comprises two layers, a surface resin layer and a cement-based layer.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION The surface material referred to in the present invention is a plate,
Any shape such as a block shape, a truncated pyramid shape, and a drum shape may be used. Further, since this serves as a formwork when filling a filler such as concrete, a concave and a convex engaging with each other may be provided at the top, bottom, left and right to prevent the inside filler from leaking therefrom.

This surface material is composed of two layers, a surface resin layer and a cement-based layer. The significance of the surface resin layer is to prevent wear and cracking of the surface material, and the existence of the resin layer greatly extends the life of the concrete (cement-based member) surface material. Therefore, it is provided in a portion that receives external factors such as wear and impact. Usually, such a surface portion is sufficient because the laid surface is received. However, they may be provided in other parts.

[0010] The resin itself may be any resin, but it is preferable that the resin adheres well to the cement body. Further, a resin that can be molded at the same time and that cures even in the presence of moisture is more preferable. Of course, the resin layer may be molded first and then put into a mold and cured at the time of molding the main body, without performing simultaneous molding and bonding or applying and curing after the cement main body is cured.

The resin that cures even in the presence of water means a resin that is not cured even if the resin before curing is in contact with moisture. In the present invention, any resin may be used as long as it is such, but a resin modified with polysulfide is preferable. This is one in which one or more units containing S are contained in the main chain or the side chain. Of course, the polymer is a collection of various molecular weights, and since the S content in the monomer unit may be different, the average amount of S is about 0 to 3 units.

More specifically, -X- (R₁-S_a)_b−
R_Two-Y- (polysulfide chain) is a main chain or
Is contained in the side chain. Where R₁, R_Two
Is a divalent methylene group (-CH_Two-) Divalent dimethyl
Ether group (-CH_TwoOCH _Two-) Divalent isopropa
A nol group (-CH_TwoCH (OH) CH_Two−) Divalent d
Tanol group (-CH_TwoCH (OH)-) and (-CH
_TwoCH_TwoOCH_TwoOCH_TwoCH_Two-), (-CH_TwoCH
_TwoO-) and the like, which may be one or more,
It may be given. Also, R₁, R_TwoAre the same but different
It may be. X and Y are -S-, -O-, -N
It is a group selected from H-._aIs for each repeating unit
An integer from 0 to 5,_bIs an integer of 1 to 50. However
And_aIs 0 for all repeating units, X or
At least one of Y is a -S- group._aAre 1-2.
5 is preferred. The above polysulfide chains form the resin structure.
It only has to be somewhere in the building.

[0013] For example, in the case of epoxy, the synthesis method comprises the addition of a sulfur-containing monomer or oligomer having a reactive functional group (including a prepolymer) and an epoxy prepolymer having two or more epoxy groups in a molecule. It is synthesized by a reaction or, for example, an addition reaction of a polysulfide polythiol and an epoxy prepolymer.

In the case of urethane, one-part urethane contains a polysulfide chain in a part or the whole of the main chain of the molecule, and two-part urethane contains in the prepolymer and / or
Alternatively, a polysulfide chain may be similarly contained in the curing agent. In the case of the two-pack type, the polysulfide resin (terminal SH) itself may be used as a curing agent.

In the case of MMA (methyl methacrylate) resin, there may be mentioned acrylate monomers having a double bond in which a polysulfide chain is bonded as a copolymerization monomer.

These resins cure even if moisture is present at the time of curing. That is, when a resin is put into a mold and concrete is poured from above before being cured, both the resin (at least the surface layer) and the concrete are uncured, but both are cured in that state.

Furthermore, this surface resin layer has
A reinforcing material may be mixed for the purpose of improving impact resistance or abrasion resistance. The reinforcing material is mixed with the resin described above, and is an aggregate material, a fiber material, a rubber material, or the like. Reinforcing materials add strength to the surface resin layer, and can absorb deformation like rubber chips, improve surface and overall wear resistance like aggregates, and crack and pull like fibers. To improve the strength against A plurality of types of reinforcing materials may be used in combination.

The aggregates include not only natural materials such as small stones, sand and gravel, but also ceramics and their crushed materials.
A crushed product may be used. The shape of the grains may be any shape. In the case other than a sphere, the expression diameter means an approximate outer size. These generally have high hardness and improve wear resistance. In order to make this more remarkable, it is also preferable to use hard aggregates such as emery and garnet.

Fiber-based materials such as glass fiber, polyamide fiber and polyester fiber have high strength.
Short fibers (1 mm to several cm) are preferred. It may be a pulp-like material. These improve the impact resistance of the protection part,
It greatly contributes to crack prevention.

As the rubber type, plastic particles,
It is a rubber chip or the like, and generally does not have high hardness. Conversely, many are flexible. In such a case, it is considered that deformation is absorbed to contribute to crack prevention.

The mixing ratio of the reinforcing material is about 1% to 50% by weight in the case of the fiber type, but can be in the range of several% to 2000% in the case of the rubber type and the aggregate type. The resin mixture obtained by mixing the reinforcing material may be a resin mixture having no void after curing or a water-permeable resin having voids.

This also varies depending on the type of reinforcing material used and is free. However, in most cases, it is natural that the effect is small unless more than several percent is mixed.

The thickness of the surface resin layer of the present invention is not particularly limited, and may be selected according to the environment at the place of use (the strength of external factors received). Although it is about 0.2 to 15 cm, it is preferably 0.5 to 3 cm in a normal sea.

The method for producing the surface material of the present invention is not particularly limited, but it is desirable to produce the surface material by utilizing the characteristics of the resin used in the present invention. For example, a resin mixed with a reinforcing material is injected into a concrete block mold (when the surface has irregularities, the irregularities are processed on the bottom surface, or a member having such a shape is laid), and a predetermined thickness of resin is injected into the concrete block mold. Before hardening (the surface layer may be hardened, for example, after the resin is hardened, the same resin may be applied again), and concrete may be poured from above. The reinforcing material may be in a form mixed with the resin, or may be mixed in a form added to the resin. In addition, after installing only the reinforcing material, a method of impregnating with a resin or the like is also possible depending on the material.
After sinking the cobblestone, the resin can be poured. It is an anchor to prevent concrete from penetrating into the resin moderately and partially after hardening. Of course, if the concrete intrudes too much downward, a net or the like may be provided in between the resin and the resin. Even in this case, there is no fear of peeling because some penetrates.

Thus, a concrete block with a surface resin layer is completed just by leaving it alone. Of course, operations and steps performed during the production of ordinary concrete blocks may be performed. For example, vibration, defoaming, etc.

As the surface material, in addition to the above-described concrete block with a curable resin, a concrete block having a normal plastic protective member on the surface can also be used. The plastic protective member may be provided with a through hole or a retaining prevention leg. Already, the molded plastic protective material can be put under the concrete mold, and the ready-mixed concrete can be poured over it to produce.

This surface material is held at a predetermined interval from the surface of the concrete retaining wall like a formwork. What is necessary is just to determine the range of the repair surface and hold this surface material at that position.
The predetermined interval is an interval at which such holding is performed.

Of course, even if only the concave portion of the concrete retaining wall is included, there are cases where the peripheral portion is included and a case where the concave portion is part of the concave portion. In addition, the recess is filled with concrete or the like as backfill material, and a resin mixture is applied for rubbing and fixing around the surface material on the front of the repair. A case of shaping and filling may be considered.

The method of holding the surface material may be the same as that of a normal mold. For holding, a form may be further used in addition to the surface material, a scaffold or the like may be used, or an anchor bar or a bolt may be used.

Further, it is not necessary to cover the entire area to be filled with the filler with this surface material, and only the surface portion which is considered to be damaged may be used, and the fine portion and the thin portion may be covered by ordinary molds (such as veneer, metal, etc.). ).

Then, if necessary, after providing a separator and reinforcing bars, a filler is filled. This filler may be of any type, such as cement-based such as concrete, resin-based, and resin mortar.

In particular, when there is a possibility that the concrete retaining wall or the ground may be wet for shore use or the like, the above-mentioned resin that hardens even in the presence of water (usually mixed with aggregate) is used. There is no need to dry it, and construction is possible regardless of the weather. This resin alone is a very good method when the filling volume of the filler is small and not much different from gluing the surface material to the retaining wall.

Further, even if inexpensive concrete is used without using such a resin as a filler, the portion in contact with the concrete, such as the back surface of the surface material, the surface of the concave portion, etc.
If this resin is applied, the adhesion will be strong, and the same effect as when the resin is used as a filler can be obtained.
This completes when the filler hardens. Needless to say, a necessary treatment such as a top coat may be performed thereafter. The construction is completed, in which the recesses of the concrete retaining wall are filled with filler and the front surface is covered by the surface material. The facing may be on the same surface as the surface of the conventional concrete retaining wall, or may protrude.

Hereinafter, the present invention will be described in more detail based on embodiments shown in the drawings.

FIG. 1 is a diagram showing an example of a method for repairing a concrete retaining wall according to the present invention. Surface material 1 on the front of the recess
Are held by anchor bars 8, reinforcing bars 9 are installed in the voids, and then a polysulfide-modified epoxy resin is applied to the surface in contact with the concrete, and fresh concrete is poured before the hardening. The shaded area is the portion of ready-mixed concrete. The ready-mixed concrete is firmly fixed to the retaining wall and the surface material by the polysulfide-modified epoxy resin. After the ready-mixed concrete is hardened, the protruding part of the anchor streaks is cut off to complete.

[0036] Thus, the conventional retaining wall is not only repaired but also more robust. Usually, the repair is less strong than the first one, but the reverse is the case with the repair method of the present invention.

FIG. 2 shows a state in which the concrete retaining wall 6 is damaged and a concave portion 7 is formed. The line shown by the broken line is the retaining wall front position at the time of construction.

FIG. 3 is a perspective view showing an example of the surface material 1 used in the present invention. The surface resin layer 3 is fixed to the concrete body 2. A groove 4 is provided on the left side and a ridge 5 is provided on the right side, and are configured to engage with each other. Such a combination may be provided not only on the left and right but also on the upper and lower sides.

[0039]

According to the method for repairing a concrete retaining wall of the present invention, there are the following advantages. (1) Since the repaired surface is covered with a surface material and the surface material is reinforced with a resin layer, it is very resistant to friction and impact. (2) The work is the same as ordinary repair work. (3) When the surface material also serves as a mold, the mold itself is unnecessary. (4) When a special resin is used, hardened concrete and ready-mixed concrete with poor adhesion can be firmly bonded.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an example of a repair method according to the present invention.

FIG. 2 is a sectional view showing an example of a location of a concrete retaining wall to which the repair method of the present invention is applied.

FIG. 3 is a perspective view showing an example of a surface material used in the repair method of the present invention.

[Explanation of symbols]

 1: Surface material 2: Concrete body 3: Surface resin layer 4: Groove part 5: Convex stripe 6: Concrete retaining wall 7: Concave part 8: Anchor bar 9: Reinforcement

 ──────────────────────────────────────────────────続 き Continuation of front page (72) Inventor Hideharu Nagata 9-2-30 Tanimachi, Chuo-ku, Osaka-shi, Osaka Prefecture F-term in Osada Giken Co., Ltd. (reference) 2E176 AA02 BB28

Claims (5)

[Claims] 1. A surface material is held at a predetermined interval in front of a concave portion caused by erosion, breakage, falling off, and collapse of a surface portion of a concrete retaining wall, and a filler is filled in a gap between the concave portion and the surface material. A method for repairing a concrete retaining wall in which the surface material is filled and fixed to the concrete retaining wall via the filler, wherein the surface material is composed of a surface resin layer and a cement-based layer. To repair concrete retaining walls. 2. A surface material having a plastic member partially exposed on the upper surface of concrete,
The method for repairing a concrete retaining wall according to claim 1, wherein the plastic member is provided with a through hole and a retaining prevention leg. 3. The concrete retaining wall according to claim 1, wherein the filler and the surface resin layer of the surface material are a mixture of a resin and an aggregate that react and harden even in the presence of moisture. Repair method. 4. The method for repairing a concrete retaining wall according to claim 1, wherein the resin of the surface resin layer of the surface material is a mixture of a reinforcing material. 5. The resin which reacts and cures even in the presence of moisture and / or the resin of the surface resin layer of the surface material is a polysulfide-modified resin.
Alternatively, the method for repairing a concrete retaining wall according to claim 4.