WO2010026702A1 - Reinforcing structure for residential concrete foundation, and reinforcing method therefor - Google Patents

Abstract

Disclosed is a reinforcing structure for reinforcing the foundation of a residence having no reinforcing bar arranged therein, by a simple construction so that the residence can be constructed even in a narrow lot and even from the inside.  Continuous fiber-reinforced members (1) are arranged in at least two longitudinally continuous grooves (4) formed in the side face of a concrete foundation (2) of an existing residence.  Adhesive materials (5) are buried in the grooves (4) to thereby fix and integrate the continuous fiber-reinforced members (1) with the foundation.  The continuous fiber-reinforced members (1) may be formed into a rod-shape having such a rugged surface as can be retained in the concrete.  An epoxy resin is applied to the side, in which the continuous fiber-reinforced members (1) are buried, to thereby prevent the reinforcing members from coming out.

Description

Reinforcement structure of residential concrete foundation and its reinforcement method

The present invention relates to a reinforcing structure of a concrete foundation of an existing house, generally called a detached house, and a reinforcing method thereof.

The foundation of a house that is generally called a detached house built by the conventional frame construction method, traditional construction method, framed wall construction method, wood prefabrication method, 2 × 4 construction method, etc. It was legalized by the Building Standards Law to arrange reinforcing bars inside. (According to Ministry of Construction Notification No. 1347 on May 23, 2000.)
However, in houses constructed before that, the construction was mixed and there were unreinforced bottomless concrete foundations, unreinforced concrete foundations with bottomless slabs, etc. However, there are some cases where this is not enough, and the house is still in use.
FIG. 6 shows a graph of the relationship between load and displacement when a bending force acts on such an unreinforced concrete foundation.
The width of the foundation used for the test is 150 mm and the height is 600 mm.
As shown in FIG. 6, when a bending force of about 34 kN is applied, the foundation is torn, and after the breaking, the bending force can no longer be endured.
Moreover, the displacement amount at the time of tearing is 1 mm or less, and it turns out that it can endure only a very slight deformation.

As a matter of course, the foundation where the reinforcing bars are not arranged has a small strength to withstand the bending force at the time of the earthquake.
When renovating a house with such an unfounded foundation, it is necessary to match not only the extension part but also the foundation of the existing part to the standard of the above Notification 1347. In addition, it was necessary to construct a concrete part with reinforcing bars and reinforced them by tying them together.
Such a reinforcing method is shown in FIGS.
As shown in FIG. 15, the surface of the rising portion a of the existing foundation is partially cut and formed so that the reinforced concrete portion b is added only to the side thereof. A part of the rising portion a and the bottom plate portion c of the existing foundation is cut off to form a reinforced concrete portion b on the side thereof.
In addition to extension and renovation, such a reinforcement method is also used for reinforcement in the case where a crack occurs in the foundation due to an earthquake or the like.

However, there are many cases where it is very difficult to adopt the above-described reinforcing method.
For example, in an existing house built on a narrow site, there is no space on the border with the adjacent land, and it may not be possible to add a foundation outside the foundation.
In addition, it is conceivable that an operator enters under the floor of the building by peeling off the floor, but it is actually very difficult to knead concrete and place it on the side of the foundation indoor side.

Japanese Patent No. 4084618 is disclosed as a method of reinforcing concrete such as elevated roads, bridge beams and floor slabs using synthetic resin rods (continuous fiber reinforcement).
The gazette is a reinforcement method when cracks occur on an elevated road or the like, and is different from a foundation reinforcement method without a reinforcing bar in a house.

The difficulty with using the above-mentioned continuous fiber reinforcing material is that it is difficult for the continuous fiber reinforcing material to be bent in the field, and the reinforcing material having a certain length is connected to ensure its continuity. That is to ensure the continuity of the reinforcing material at the corners of the foundation.
Japanese Patent No. 4084618

Issues to be solved include making it possible to reinforce the foundations where the reinforcing bars of the house are not laid with simple construction, enabling construction even in small sites, enabling construction from the indoor side, etc. It is.

The reinforcing structure of a residential concrete foundation according to the present invention includes continuous fiber reinforcement in at least two longitudinally continuous concave grooves formed on at least one of the left and right side surfaces of the existing concrete foundation. Place the material,
Adhering an adhesive in the groove and fixing a continuous fiber reinforcement to integrate with the concrete foundation,
On the side surface of the concrete foundation to which the continuous fiber reinforcement is fixed,
The continuous fiber reinforcing material and the adhesive are protected by painting or applying epoxy resin, polymer cement or the like, or attaching a board.

In another reinforcing structure of a residential concrete foundation according to the present invention, two concave grooves are formed in parallel with a space between the upper and lower sides of the concrete foundation.
In another reinforcing structure for a residential concrete foundation according to the present invention, the two concave grooves are formed so as to be slanted on the side surface of the concrete foundation so as to cross each other and intersect each other.
In addition to the two recessed grooves, the recessed structure is also formed in the vertical direction of the side surface of the concrete foundation, and the continuous fiber reinforcing material is fixed in these. It is what.
Another residential concrete foundation reinforcing structure according to the present invention is such that a part of two or more continuous fiber reinforcing materials are overlapped with each other in a concave groove with a length of 30 times or more of the diameter of the reinforcing material. It is embedded with material and integrated and fixed.

Furthermore, the reinforcing structure of the residential concrete foundation according to the present invention is as follows.
It is a corner of the concrete foundation, and a concave groove that extends in the lateral direction across the corner is provided on the side surface.
A straight continuous fiber reinforcement is placed in the groove so that its end reaches near the corner,
Arrange the saddle-shaped continuous fiber reinforcing material bent in advance in the middle so as to straddle the left and right according to the corner,
The ends of the linear continuous fiber reinforcement and the continuous fiber reinforcement are overlapped,
It is characterized in that an adhesive is embedded in the recessed groove and a continuous fiber reinforcing material is fixed.
Furthermore, the reinforcing structure of the residential concrete foundation according to the present invention is as follows.
In the T-shaped butting part of the concrete foundation, while forming a through-hole spanning the intersection,
Concave grooves connected to the through holes are continuously formed on the left and right of the intersection,
In the through hole of the intersecting part, a continuous continuous fiber reinforcing material is arranged to project the left and right end parts from the through hole into the groove,
The end of continuous fiber reinforcing material arranged on the left and right of the intersecting part and the end of the continuous fiber reinforcing material overlap each other, and the continuous fiber reinforcing material is fixed by embedding an adhesive in the recessed groove and through hole. is there.

Another method for reinforcing a concrete foundation of a house according to the present invention is to form a groove with a cutter on at least one of the left and right side surfaces of a concrete foundation of an existing house, and continuous fiber reinforcement in each groove. Place the material,
Embedding an adhesive in the groove and fixing the continuous fiber reinforcement in the groove and integrating it with the fabric foundation,
On the side surface of the concrete foundation to which the continuous fiber reinforcement is fixed,
The continuous fiber reinforcing material and the adhesive are protected by painting or applying epoxy resin, polymer cement or the like, or attaching a board.
Furthermore, the method for reinforcing other residential concrete foundations according to the present invention is as follows:
The continuous fiber reinforcement is embedded and fixed to the indoor side surface of the concrete foundation.

The present invention has the above-described configuration and achieves at least one of the following effects.
<a> Since a concave groove is formed on the surface of a concrete foundation and a continuous fiber reinforcing material is embedded and fixed therein, it is not necessary to increase the width of the foundation itself, and construction on a small site is also possible.
In addition, construction is possible in a much shorter period of time and costs are lower than in the construction method in which a new foundation is attached to the side of an existing foundation.
<B> Workers enter under the floor, and it is possible to form grooves on the indoor side of the foundation and to embed and fix continuous fiber reinforcements. Construction is possible.
<C> Continuous fiber reinforcement is used as a substitute for the reinforcing bar and does not rust, so even if it is embedded in the concave groove formed on the side of the foundation, it does not require fog like a reinforcing bar and is equivalent to or more than the reinforcing bar. Strength can be secured.
<D> By forming a concave groove, embedding a continuous fiber reinforcing material therein, and fixing the periphery with an adhesive, it is difficult for the reinforcing material to be detached from the concave groove. It becomes a reinforcing material that can withstand a large bending that cannot be compared.
<E> Concave grooves are formed not only in the longitudinal direction of the foundation but also in the shape of a plow or in the vertical direction, and the continuous fiber reinforcing material is embedded and fixed, thereby making it possible to reinforce the foundation integrally.
<F> Protecting the continuous fiber reinforcing material and adhesive by painting or applying epoxy resin or pasting the board, the reinforcing material will not deviate from the groove, and the adhesive will be more sticky. The reinforcement structure can withstand a greater bending force.
<G> continuity of the reinforcing material is ensured even at corners and T-shaped butted parts by overlapping the ends of continuous fiber reinforcing materials or by using continuous fiber reinforcing materials bent in a bowl shape It becomes possible to do.

Hereinafter, the present invention will be described in detail based on the embodiments shown in the drawings.
<1> Continuous fiber reinforcing material The continuous fiber reinforcing material 1 used in the present invention is formed by impregnating a continuous fiber with a fiber binder and curing it, and is formed by bundling only a unidirectional reinforcing material or continuous fiber, Or a general term for woven materials.
The reinforcing fiber of the continuous fiber reinforcing material is a continuous fiber such as homopolymerized aramid fiber, copolymerized aramid fiber, carbon fiber, glass fiber, high strength polyethylene fiber, high strength polyarylate fiber, PBO fiber or vinylon fiber. Is used.
It is possible to adopt not only one type of fiber but also a plurality of types.
These reinforcing fibers are bonded to the reinforcing fibers by using one or more of epoxy resin, epoxy acrylate resin, vinyl ester resin, unsaturated polyester resin, or cement bonding material. To do.
The shape of the continuous fiber reinforcing material 1 is a rod shape with irregularities on the surface, a rectangular cross-sectional shape having protrusions that can secure adhesion, a braided shape, a lattice shape, a strand cross-sectional shape, and a sanding treatment on the surface. It is effective to ensure adhesion with adhesive or concrete, such as shape.

<2> Strength of Continuous Fiber Reinforcement Material The continuous fiber reinforcement material 1 has a very high strength compared to ordinary reinforcing bars, and a sufficient reinforcement effect can be expected with a reinforcement material having a small cross-sectional area.
As an example, an aramid rod manufactured by Koshin House Caring Co., Ltd., which is the applicant of the present invention, trade name Power Alast FA (an irregular cross-section rod in which a copolymerized aramid fiber (trade name Technora) is integrated with a vinyl ester resin) has an outer diameter of 8 mm. The guaranteed yield strength is 81.4kN, which is almost equal to the tensile strength (286.5mm ² × 295N / mm ² = 84.5kN) of the D195 reinforcement of SD295A. The amount of reinforcement specified in the Ministry of Construction Notification No. 1347 Since one reinforcing bar with a diameter of 12 mm or more is to be placed on each of the upper end of the foundation and the bottom bottom plate, if the high-strength continuous fiber reinforcing material 1 is used, the amount of reinforcing bars exceeding the required amount It can be seen that it is possible to easily arrange the proof reinforcement.
The continuous fiber reinforcement 1 generally has a low specific gravity, and in the case of an aramid rod, it has a specific gravity of only about 1.31 g / cm ² .
For this reason, compared with a reinforcing bar with a specific gravity of 7.8 cm ³ , it is significantly lighter as a reinforcing material, and it is easy to work in a narrow space under the floor, which is a great merit.
In addition, since it is made of resin, it does not rust, does not require fogging like a reinforcing bar, and there is no problem even when it is embedded in a concave groove formed on the surface.

<3> Concave groove Concave groove 4 is formed on one of the left and right side surfaces of rising portion 3 of concrete cloth foundation 2 of an existing house, on the side surface that is the indoor side in the embodiment.
In the figure, houses are omitted.
The groove 4 is formed by cutting with a U-shaped cutter (diamond cutter). In the embodiment shown in FIG. 1, the longitudinal direction of the foundation is appropriately spaced in the vicinity of the upper end and the lower end of the rising portion 3 of the concrete foundation 2. That is, the concave grooves 4 that are continuous in the horizontal direction are formed.
Since the U-cutter has a small surface for cutting concrete, the use of the U-cutter integrated with the dust collector can greatly reduce the generation of dust and can greatly improve the work environment.
In addition, the concave groove is formed by cutting a thin groove with an appropriate concrete cutter at an appropriate interval (outer diameter of continuous fiber reinforcing material to be inserted and fixed + about 2 to 10 mm), and using a chisel etc. in this thin groove It can also be formed by scraping.
As the cross-sectional shape of the groove 4, various shapes such as a U-shape, a rectangle, a valley shape, and a trapezoid whose width is wider at the bottom can be adopted.
In the embodiment, the width 2 of the foundation 2 is 150 mm, the height H is 600 mm, and the concave grooves 4 are formed at positions 80 mm and 400 mm from the upper end of the side surface.

<4> Embedding the reinforcing material The continuous fiber reinforcing material 1 (trade name Power Alast FAΦ8) is embedded in the groove 4 described above, and the adhesive 5 is filled so as to fill the periphery of the continuous fiber reinforcing material 1. The continuous fiber reinforcement 1 is fixed in the groove 4.
As the adhesive 5, an epoxy resin, an epoxy acrylate resin, a vinyl ester resin, an unsaturated polyester resin, a cement binder, or the like can be used, and one or more of them are used.
In particular, an epoxy adhesive containing aramid fibers manufactured by Koshin House Caring Co., Ltd., which is the patent applicant of the present application: trade name Power Alast is excellent in both adhesive strength and strength, and can be suitably used.

<5> Action The test body T1 reinforced as described above is shown in FIGS. 2 (A) and 2 (B).
In this test body T1, the reinforcing material 1 is simply embedded and fixed in the concave groove 4, and no resin is applied to the side surface of the foundation 2 or a sheet is not adhered.
It is assumed that due to the earthquake, a bending force that acts as an upward force in the left and right intermediate portions and a downward force in the left and right intermediate portions acts on the test body T1.
The relationship between the load and the displacement at this time is shown in the graph of FIG.
When the bending force acts, the concrete is torn at about 40 kN, but the bending force is received by the continuous fiber reinforcing material 1 to withstand a larger bending force, and even after removing the bending load, the elastic force of the reinforcing material 1 It can be understood that the amount of displacement is reduced and the displacement is reduced.

<6> Application FIG. 3 shows a test of the first example in which the concave groove 4 of the concrete foundation 2 is formed, and the epoxy resin 6 is further applied on the side surface where the continuous fiber reinforcing material 1 is embedded and fixed. It is the body T2.
An epoxy resin adhesive 6 (trade name Power Alast) is applied to almost the entire surface of one side of the rising portion 3.
FIG. 8 shows a graph of a load and a displacement amount obtained by applying a bending force to such a specimen T2.
After the concrete foundation 2 is torn, the continuous fiber reinforcing material 1 and the applied epoxy resin adhesive 6 (trade name Power Alast) receive the bending force beyond it, and finally the displacement is caused by the elastic force of the reinforcing material 1. Is getting smaller.
That is, it can be understood that by applying the adhesive 6 to the side surface of the foundation 2, it becomes possible to withstand a greater bending force.
In addition, the epoxy resin can be applied, polymer cement or the like can be applied or applied, or the continuous fiber reinforcement 1 and the adhesive can be protected by attaching a board.

<7> Overlap of Continuous Fiber Reinforcement In Example 2 shown in FIG. 4, two continuous fiber reinforcements 1 are arranged in the concave groove 4, and in order to ensure the continuity, a part of them Is a test body T3 of an example in which the sample is overlapped with a length of 30 times or more of its diameter, embedded with an adhesive 6 and fixed and integrated.
In the concave groove 4 described above, the continuous fiber reinforcing material 1 (trade name Power Alast FAΦ8) is provided with an overlap portion O having a length of 30 times or more of the diameter (here 30 cm), and the adhesive 6 Last (fixed) and integrated.
FIG. 9 shows a graph of the load and the amount of displacement when a bending force is applied to the specimen T3.
Similar to the graph of FIG. 7, the concrete is torn at about 40 KN, but it can be seen that the subsequent bending force is received by the continuous fiber reinforcement 1 and can withstand a large bending force.
Thus, it can be seen that the continuous fiber reinforcing material 1 maintains the continuity as a reinforcing structure by providing an overlap of 30 times or more in diameter in the concave groove 4 and adhering and integrating them with the adhesive 6.

<8> Continuous Fiber Sheet Affixation FIG. 5 shows that a continuous fiber reinforcing material is disposed on an unreinforced concrete foundation, which has already been shown in the section of the background art, and a continuous fiber sheet 7 is provided on a part of the surface. It is the test body T4 of the Example which affixed.
This specimen is diverted from the above-mentioned unreinforced concrete foundation that has been subjected to a bending test and destroyed.
A crack 8 is generated in an intermediate portion of the concrete foundation 2, and a continuous fiber sheet 7 that is an aramid fiber is pasted so as to straddle the crack 8.
FIG. 10 shows a graph of the load and the amount of displacement when a bending force is applied to the specimen T4.
It can be seen that the continuous fiber sheet 7 and the concrete portion can withstand the initial bending force and can withstand a load larger than that reinforced only by the continuous fiber reinforcement 1.
Thereafter, the continuous fiber reinforcement 1 is peeled off at the crack portion to temporarily reduce the load. However, the continuous fiber reinforcement 1 can bear the bending load again, and the maximum load is only the continuous fiber reinforcement 1. It becomes equivalent to the case where it is reinforced.
In this way, even unreinforced concrete foundations that have already been cracked by bending force can be restored and reinforced beyond the bending strength originally possessed by using this method.
The continuous fiber sheet 7 is not only used for repairing when such a crack 8 occurs, but the continuous sheet 7 is attached to the entire length of the side surface of the foundation concrete 2 with an adhesive, and the reinforcing material is detached from the groove 4. It is also possible to prevent this from occurring and to integrate the continuous fiber reinforcement 1 and the concrete foundation 2.

<9> Arrangement of Continuous Fiber Reinforcement Material The continuous fiber reinforcement material 1 not only forms a horizontal concave groove 4a and embeds it therein, but also forms a concave groove 4b in a slanted shape, It is also possible to embed in (Fig. 11)
Alternatively, it is also possible to form the concave groove 4c in the vertical direction and embed the continuous fiber reinforcing material 1 therein.
In this way, the continuous fiber reinforcing material 1 partially intersects, so that the reinforcing material 1 embedded in one side surface is continuous, and the entire concrete foundation 2 can be more integrated.

<10> Corner part Fig. 12 shows the construction state of the corner part of the concrete foundation 2, and a continuous concave groove 4 is formed in the corner part made of the concrete foundation 2 forming a right angle. In this case, the continuous fiber reinforcing material 9 formed at right angles is embedded.
Both ends of the continuous fiber reinforcing material 9 formed at a right angle are overlapped with the linear continuous fiber reinforcing material 1 embedded in the concave groove 4 until just before the ends, respectively, to ensure the strength and continuity at the corner portion. Is.

<11> Abutting portion FIG. 13 shows an example in which the continuity of the continuous fiber reinforcement 1 in the T-shaped abutting portion of the concrete foundation 2 is ensured.
The continuous fiber reinforcing material 10 connected to the hole penetrated through the butted portion is passed through, and both end portions thereof are overlapped with the continuous fiber reinforcing material 1 embedded in the concave grooves 4 formed in the concrete foundations 2 on both the left and right sides, respectively. Is ensured.

<12> Reinforcement around Ventilation Port FIG. 14 shows an example in which reinforcement around the ventilation port 11 is performed, and a concave groove 4d is horizontally formed below the continuous fiber reinforcement 1 cut off by the ventilation port 11. Then, the auxiliary continuous fiber reinforcing material 12 is disposed therein, and the continuous fiber reinforcing material 13 partially overlapped with the continuous fiber reinforcing material 1 is embedded in the concave groove 4e obliquely from the left and right, so that the continuous fiber reinforcing material 1 This is an example in which continuity is ensured.

1 is a perspective view of a first embodiment of the present invention. A specimen with no resin applied to the foundation, (A) is a side view and (B) is a cross-sectional view. It is a test body of the first embodiment, (A) is a side view, (B) is a sectional view. Side view of specimen of second embodiment It is a test body of the third embodiment, (A) is a side view, (B) is a sectional view. Graph showing load and displacement in an unmuscle foundation The graph which shows the load and displacement amount in the test body of FIG. The graph which shows the load and displacement amount in the test body of the first embodiment The graph which shows the load and displacement amount in the test body of the second embodiment The graph which shows the load and displacement amount in the test body of the third embodiment Side view of a concrete foundation according to another embodiment Perspective view of an embodiment of reinforcement at a corner A perspective view of an embodiment of reinforcement at the butt section Side view of an example of reinforcement around a vent Cross section of conventional reinforcement method Cross section of conventional reinforcement method

1: Continuous fiber reinforcement 2: Concrete foundation 3: Rising part 4: Groove 5: Adhesive 6: Epoxy resin 7: Continuous fiber sheet 8: Crack 9: Continuous fiber reinforcement 10: Continuous fiber reinforcement 11: Ventilation opening 12: Continuous fiber reinforcement 13: Continuous fiber reinforcement

Claims (9)

Of the left and right side surfaces of the concrete foundation of the existing house (detached house), at least two continuous grooves in the longitudinal direction formed on the side surface on one side are arranged with continuous fiber reinforcements, respectively.
An adhesive is embedded in the concave groove, and a continuous fiber reinforcement is fixed and integrated with the foundation,
On the side surface of the concrete foundation to which the continuous fiber reinforcement is fixed,
Reinforcement structure for residential concrete foundation that protects continuous fiber reinforcement and adhesive by painting or applying epoxy resin, polymer cement, etc., or attaching a board. The reinforced structure for a residential concrete foundation according to claim 1, wherein the two concave grooves are formed in parallel at an appropriate distance from each other above and below the side surface of the concrete foundation. The reinforcing structure for a residential concrete foundation according to claim 1, wherein the two concave grooves are formed so as to be slanted and slanted on the side surface of the concrete foundation. The groove is formed in the vertical direction of the side surface of the concrete foundation in addition to the two grooves, and the continuous fiber reinforcing material is fixed in these grooves. The reinforcing structure of a residential concrete foundation according to item 1. A part of two or more continuous fiber reinforcing materials are overlapped in a concave groove with a length of 30 times or more of the diameter of the reinforcing material, embedded with an adhesive material, and fixed integrally. The reinforcing structure for a residential concrete foundation according to any one of claims 1 to 4. It is a corner of the concrete foundation, and a concave groove that extends in the lateral direction across the corner is provided on the side surface.
A straight continuous fiber reinforcement is placed in the groove so that its end reaches near the corner,
Arrange the saddle-shaped continuous fiber reinforcing material bent in advance in the middle so as to straddle the left and right according to the corner,
The ends of the linear continuous fiber reinforcement and the continuous fiber reinforcement are overlapped,
Reinforcement structure for residential concrete foundation, characterized in that adhesive is embedded in the groove and a continuous fiber reinforcement is fixed. In the T-shaped butting part of the concrete foundation, while forming a through-hole spanning the intersection,
Concave grooves connected to the through holes are continuously formed on the left and right of the intersection,
In the through hole of the intersecting part, a continuous continuous fiber reinforcing material is arranged to project the left and right end parts from the through hole into the groove,
The end portions of the continuous fiber reinforcing material arranged on the left and right of the intersecting portion are overlapped with the end portions of the continuous fiber reinforcing material,
A reinforcing structure for a residential concrete foundation, characterized in that a continuous fiber reinforcing material is fixed by embedding an adhesive in the recessed groove and the through hole. Of the left and right side surfaces of the concrete foundation of the existing house, at least one side surface is formed with a ditch by a cutter,
Place continuous fiber reinforcement in each groove,
Embedding an adhesive in the groove and fixing the continuous fiber reinforcement in the groove and integrating it with the fabric foundation,
On the side surface of the concrete foundation to which the continuous fiber reinforcement is fixed,
Reinforcement method for residential concrete foundation by protecting continuous fiber reinforcement and adhesive by painting or applying epoxy resin, polymer cement, etc., or pasting board. The method for reinforcing a residential concrete foundation according to claim 8, wherein the continuous fiber reinforcing material is embedded and fixed in a concave groove formed in a side surface on the indoor side of the concrete foundation.

Images