EP0233182A1

EP0233182A1 - Device for reinforcing a concrete wall and the method thereof

Info

Publication number: EP0233182A1
Application number: EP85905338A
Authority: EP
Inventors: Naohiko Gobayashi
Original assignee: Individual
Current assignee: Individual
Priority date: 1985-08-16
Filing date: 1985-10-18
Publication date: 1987-08-26
Also published as: WO1987001153A1; AU5065185A

Abstract

Un dispositif de renforcement d'un mur en béton comprend un siège de montage et un assemblage de capsule comprenant un ajutage d'injection, une capsule en forme de soufflet remplie d'agent de renforcement, un ressort hélicoïdal servant à exprimer la capsule, une enveloppe, un capuchon avant et un capuchon arrière. Le dispositif comprend en variante un capuchon arrière possédant un trou à travers lequel est introduite une tige creuse pour comprimer le ressort hélicoïdal en le tirant en arrière. Un procédé de renforcement d'une paroi en béton consiste à fixer le siège de montage sur la fissure de la paroi, à monter l'assemblage de capsule sur le siège de montage et à exprimer la capsule. Ce procédé consiste de préférence à percer un trou dans la paroi en béton, à y introduire un tampon à injection dilatable, et à monter l'assemblage de capsule sur le tampon pour réparer une fissure provoquée par la séparation de la couche de mortier.A concrete wall reinforcement device includes a mounting seat and a capsule assembly comprising an injection nozzle, a bellows-shaped capsule filled with reinforcing agent, a coil spring for expressing the capsule, a envelope, a front cap and a rear cap. The device alternatively comprises a rear cap having a hole through which a hollow rod is introduced to compress the helical spring by pulling it back. A method of strengthening a concrete wall is to fix the mounting seat on the wall crack, to mount the capsule assembly on the mounting seat and to express the capsule. This method preferably consists in drilling a hole in the concrete wall, in introducing an expansion injection pad therein, and in mounting the capsule assembly on the pad to repair a crack caused by the separation of the layer of mortar.

Description

DEVICE FOR REINFORCING A CONCRETE WALL AND THE METHOD THEREOF

TECHNICAL FIELD

The present invention relates to a device for reinforcing a concrete wall and the method thereof.

BACKGROUND ART

It is well known that a concrete wall has cracks unavoidably due to its shrinkage. Therefore, a concrete building generally has cracks on the wall with the lapse of time. And, the finishing mortar or tile layer of a concrete wall often becomes parted from the concrete wall body.

Accordingly, it has been proposed to inject a reinforcing agent into the cracks formed in a concrete wall. Also, it has been proposed to inject grout into the crack due to the parting of a mortar layer from a concrete wall body.

However, these prior art generally have a disadvantage that they require the operator to stay at site for a long time. Besides, they are apt to be injected excessively. Consequently, they lead to the increasing of the reinforcing cost. And, they cause the mortar layer adajacent to the crack to be apt to part from the concrete wall body, thereby resulting in uneven appearance.

DISCLOSURE OF INVENTION

It is an object of the present invention to provide a device for reinforcing a concrete wall and the method thereof, which eliminate all the disadvantages of the prior art.

The concrete wall referred herein includes the outer wall surface, the inner wall surface, the ceiling surface and the floor surface of a concrete building and other concrete structures. It is another object of the present invention to provide a device for reinforcing a concrete wall and the method thereof which is able to reinforce a concrete wall reasonably by injecting a reinforcing agent into the cracks formed in a concrete wall.

It is a further object of the present invention to provide a method for reinforcing efficiently a concrete wall by injecting a reinforcing agent into the cracks formed due to the parting of a mortar layer from a concrete wall body.

In order to achieve these objects, a device for reinforcing a concrete wall according to the present invention comprises a setting seat having a disc portion and a tube portion, said setting seat. being adapted to be attached on a crack of the concrete wall, and a capsule assembly detachably set to said setting seat, said, capsule assembly comprising an injection nozzle adapted to. be set detachably to said tube portion of said setting seat, a bellows shaped capsule filled with the reinforcing agent and adapted to be engaged with the base portion of said injection nozzle, a coil spring for squeezing the bellows shaped capsule through the disc in order that the reinforcing agent in the capsule is injected into the crack of the concrete wall through the passage of said injection nozzle and said setting seat, a case accommodating the injection nozzle, the capsule and the coil spring, a front cap which is detachably connected to the jfront end of the case and into which the screw portion of said nozzle is inserted, and a rear cap which is detachably connected to the rear end of the case and to which the rear end of said coil spring is fixed.

It is preferable that the rear cap has a hole through which a hollow rod is inserted, said hollow rod having a ring at the rear end thereof and a hole in the middle portion thereof, said ring being adapted to be used for pulling said hollow rod rearward so that the coil spring is compressed with the aid of a disc which is fixed to the front end of said hollow rod, and said hole being adapted to insert therethrough the cotter pin so as to maintain the hollow rod in the pulled state. Moreover, in order to achieve said objects, the method for reinforcing a concrete wall according to the present invention comprises attaching a setting seat on a crack of a concrete wall with the aid of an adhesive agent, setting a capsule assembly to said setting seat by connecting the screw portion of the injection nozzle to the tube portion of the setting seat, said capsule assembly being adapted to squeeze the capsule, and squeezing the capsule so as to inject the reinforcing agent to the crack of the concrete wall through the passage of the injection nozzle and the setting seat.

It is also preferable that the method for reinforcing a concrete wall according to the present invention comprises drilling a hole having a suitable diameter and a depth piercing into the concrete wall body to some extent through the mortar layer at a suitable place on the crack formed due to the parting of the mortar layer from the surface of the concrete wall body, cleaning said hole, inserting into said hole an expandable injection plug having a base portion and a front portion, said plug splitting into at least three portions at the end thereof, said portions each having a small hole in the middle portion thereof and a tapered openning at the front end thereof, fixing the expandable injection plug so as to expand in the hole in the concrete wall by striking the pin into said tapered openning, and setting the capsule assembly to the base portion of said expandable injection plug, . Other objects, advantages and novel features of the present invention will become more apparent from the following detailed description of the preferred embodiment when taked in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

Fig. 1 is a vertical sectional view of the device according to a preferred embodiment of the present invention;

Fig. 2 and 3 illustrate the setting of the device of Fig. 1 on the crack of the concrete wall; Fig. 4 is a vertical sectional view of the capsule assembly according to another embodiment of the present invention;

Fig. 5 is an end view taken along the line V-V of Fig. 4;

Fig. 6 illustrates the hole formed to be inserted by the expandable injection plug according to a further embodiment of the present invention;

Fig. 7 is a front view of the expandable injection plug to be inserted into the hole of Fig. 6;

Fig. 8 is a vertical sectional view of the expandable, injection plug of Fig. 7;

Fig. 9 illustrates the setting of the capsule assembly in the holes of Fig. 6 by the expandable injection plug;

Fig. 10 illustrates the state of injection of the reinforcing agent according to this preferred embodiment of the present invention.

Fig. 11 is a fragmentary sectional view of the pressing plate and the adapter according to a still further embodiment of the present invention;

Fig. 12 illustrates the connecting of the adapter with the pressing plate of Fig. 11 to the expandable injection plug;

Fig. 13 illustrates the setting of the capsule assembly to the adapter of Fig. 11.

BEST MODE FOR CARRYING OUT THE INVENTION

Referring to Fig. 1 illustrating an embodiment of the device according to the invention, it comprises a setting seat(10) adapted to be attached on the crack of the concrete wall with the aid of the adhesive agent and a capsule assembly ( 20 ). The capsule assembly (20) comprises ann injection nozzle(21) adapted to be engaged detachably with said setting seat(10), a bellows shaped capsule(22) for the reinforcing agent which is connected directly to said injection nozzle(21), a coil spring(23) for squeezing the bellows shaped capsule(22), a case accommodating said injection nozzle(21), capsule(22) and coil spring(23), a front cap(25), and a rear cap(26).

The siecting seat (10) is formed with a disc portion(ll) having area sufficient to support the capsule assembly(20) and a tube portion(12) protruding centrally in which a female thread is formed/ to which a screw portion(21') of said injection nozzle(21) is adapted to be engaged. In the center, said disc portion(11) comprises a small hole.

The injection nozzle(21) having, a passage(29) for the reinforcing agent from the capsule (22) axially in its interior consists of a base portion(21") adapted to be engaged detachably with a neck portion (22') of the caρsule(22), a hexagonal portion ( 21'" ) connected to said base portion(21") and providing suitable handle and a screw portion(21') connected to said hexagonal portion. The lenth of said screw portion(21') is a little longer than that of the tube portion(12) of the setting seat(10). The bellows shaped capsule(22) for the reinforcing agent is made of synthetic resin and has an axially flexible bellows shape. It is made preferably about 30-80 CC in volume. And, in the neck portion (22'), it is formed with male screw, to which the female thread portion of the inj ection nozzle ( 21 ) is connected .

At the front end of the coil spring(23) is fixed a disc(27), and at the rear end of the coil spring(23) is fixed a rear cap(26). The case(24) for accommodating said injection nozzle(21), capsule(22) and coil spring(23) has a front end which is connected detachably to a front cap(25), the rear surface of which is abutted on the end face of said hexagonal portion (21") of the injection nozzle(21). Abutting on the front surface of the front cap(25), a hexagonal nut (28) is locked onto the screw portion(21') of the injection nozzle(21). And, the rear end of the case(24) is connected detachably to the rear cap(26) to which said coil spring(23) is fixed. The length of the case(24) is a little longer than the length that is sufficient to accommodate a part of said injection nozzle(21), capsule(22) and coil spring( 23).

The method for reinforcing the concrete wall using the reinforcing device according to the invention is as follows. At first, the setting seat(10) is attached on the crack of the concrete wall with the aid of the adhesive agent made of, for example, expoxy resin. On the remaining part of the crack of the concrete wall other than the part where the setting seat is attached, the seal agent is pasted. And, the reinforcing agent made by mixing, for example, the epoxy resin and polyamidoaimine at suitable proportion at site is filled in the capsule(22). After the base portion (21") of the injection nozzle(21) is engaged with the neck portion(22') of the capsule(22) thus filled, the screw portion(21') of the injection nozzle(21) is fitted with the front cap(25) and locked with the hexagonal nut(28). Thereafter, the front end of the case(24) is connected to the front cap(25) which is engaged with the injection nozzle(21) such that it accommodates the capsule(22) therein.

After the screw portion(21') of the injection nozzle(21) is connected to the tube portion of the setting seat, the rear cap(26) to which the rear end of the coil spring(23) is fixed is connected to the rear end of the case(24), thereby the disc(27) fixed to the front end of the coil spring(23) pushes the bottom of the caρsule(22) due to the restoring action of the coil spring(23) to inject the reinforcing agent in the capsule(22) into the crack of the concrete wall through the passage(29).

While the reinforcing agent is injected in this manner, the capsule assembly(20) is self supported by the setting seat(lθ). And/ the case(24) is made of transparent material such as acryl resin or polycarbonate resin/ which makes it possible to check the volume of the capsule(22) without removing the case(24). For the purpose of refilling the reinforcing agent in the capsule(22), the front end of the case(24) is separated from the front cap(25) and the capsule(22) is separated from the base portion(21") of the injection nozzle(21).

When the injection is completed, the capsule assembly(20) is separated from the setting seat (10) and the setting seat (10) is removed from the concrete wall by the suitable fusion means.

As described above, because this method comprises attaching the setting seat on the concrete wall and setting the capsule assembly to the setting seat/ this device can be set in various direction.

Fig. 4 and 5 illustrate another embodiment of the capsule assembly according to the inventin. This assembly is similar to the embodiment described above, but it comprises a hollow rod (30) which is inserted through the hole (26') of the rear cap (26) and is fixed to the disc(27) at the front end thereof. Said hollow rod(30) has a hole(30') to be inserted by the cotter pin(31) at the middle portion and a hole to be engaged with a ring (32).

The method for reinforcing a concrete wall using the capsule assembly according to this embodiment is as follows. At first, as the embodiment described above, the setting seat(10) is attached on the crack of the concrete wall with the aid of the adhesive agent. And, by pulling the ring (32) engaged with the rear portion of the hollow rod(30) rearward, the disc(27) is positioned so that it does not squeeze the capsule (22) and the cotter pin(31) is inserted into the hole(30') formed in the middle portion of the hollow rod(30). The cotter pin(31) is abutted on the rear cap(26) by the restoring force of the coil spring(23). And, after separating the front end of the case(24) from the front cap(25), the neck portion(22') of the capsule(22) filled with the reinforcing agent at site is connected to the base portion(21') of the injection nozzle(21) engaged with the front cap(25). Thereafter, the capsule assembly(20) thus prepared is connected to the tube portion(12) of the setting seat(10). And, by pulling out the cotter pin(31) from the hole(30') in the middle portion of the hollow rod(30), the compressed coil spring(23) is restored, thereby squeezing the capsule(22). As a result, the reinforcing agent filled in the capsule (22) is injected through the passage(29) into the crack of the concrete wall. The separating the capsule assembly (20) and removing the setting seat(10) when the injection is completed are carried out as those of the embodiment described above.

As described above, this method comprising applying the thrust by the coil spring(23) to the reinforcing agent in the capsule(22) enables the injection of the reinforcing agent to be carried without the opera¬tor's long period stay at site.

Fig. 6 to 10 illustrate further embodiment of the method according to the invention. The method according to this embodiment is used to the crack or clearance ( 43 ) formed due to the parting of the mortar layer(42) from the surface of the concrete wall body (41).

At first, the state of crack (43) is checked and suitable number of holes (44) are formed at suitable places by the drill. For example, when the thickness of mortar layer(42) is 20-25rnm and the clearance (43) is 1-3mm, the drill having a diameter of 10-11mm is used and the hole(44) is drilled through the mortar layer(42) into the concrete wall body(41) by about

12mm.

Thereafter, the hole(44) is cleaned, for example, by the air gun, and an expandable injection plug(50) is inserted. And a pin(57) is struck into the expandable injection plug (50) and therefore the expandable injection plug(50) is fixed in the hole(44) due to the expansion thereof.

The expandable injection plug (50) as shown in Fig. 7 and 8 is the hollow body made of a metal having a suitable diameter and length. Also, it consists of a base portion(51) having a female thread(53) on the inner surface thereof and a front portion(52) having a tapered opening (54) whose diameter is reduced frontward. Moreover, this expandable injection plug(50) has more than three split (55) (four split is shown in Fig. 7 and 8) extending from the front end to the middle of the plug (50) and has a hole (56) in the middle of splitted end respectively. After connecting the capsule assembly(20) to the expandable injection plug(5) fixed in the hole(44) in the concrete wall by connecting the screw portion (21') of the injection nozzle(21) of the capsule assembly(20) to the female thread(53) of the expandable injection plug(50), the cotter pin(31) is pulled out from the hole(30') of the hollow lever(30), thereby the reinforcing agent in the capsule(22) is injected into the clearance through the splits (55) and holes (56) of the expandable injection plug(50). It is preferable that suitable number of the devices make groups by connecting their ring(32) with a string(48) as shown in Fig. 9 so that they can be maintained safely even if some of them are parted from their setting position. Because the reinforcing agent is injected as described above, if the injection resistance is increased depending on the state of the clearance, that is, the clearance is narrowed, the excessive injection pressure would be vanished and the state of equilibrium is reached .

Therefore, excessive injection is prevented and the injection is automatically controlled depending on the state of the clearance. When the injection is completed, the string is withdrawn from the ring of the capsule assembly and the capsule assembly is separated from the setting seat.

While the embodiment has been described with reference to the mortar covered concrete wall, it can also be made to the tile covered concrete wall when it is carried out by utilizing the joint portion of them

Fig. 11 to Fig. 13 illustrate further embodiment of the method according to the invention. The method of this embodiment is used to where the crack formed due to the parting of the mortar from the surfaceof the concrete wall body reaches to considerable area thereby causing the reinforcing agent to be injected excessively and making the mortar surface to be uneven even after the reinforcing work is carried out.

Therefore, this embodiment comprises a step consisting of using the parts for preventing the parting of mortar layer from the concrete wall body in addition to the method described above.

The parts for preventing the parting of mortar layer from the concrete wall body consist of a pressing plate(61) and an adapter(65). The pressing plate(61) is made in the shape of circular plate having the area sufficient to press the mortar surface to some extent. It has a hole(64) in which a screw portion(67) of the adapter(65) is inserted. The adapter(65) consists of a hexagonal head portion(66) having a female thread (68) on the inner surface and a screw portion(67) having a passage therein.

The method according to this embodiment comprises the step of the connecting the screw portion(67) of the adapter(65) which is inserted into the hole(64) of the pressing plate(61) to the female thread(53) of the expandable injection plug (50) which is fixed to the concrete wall in addition to the step of the embodiment described above. In other words, after the adapter(65) with the pressing plate(61) is connected to the expandable injection plug(50) so that the front surface(62) of the pressing plate(61) press the mortar surface of the concrete wall, the capsule assembly(20) is connected to the female thread (68) of the adapter (65) and following step is continued. INDUSTRIAL APPLICABILITY

In view of the foregoing, it will be seen that the present invention provides an improved device for reinforcing a concrete wall and the method thereof which can be used without the operator's long period stay at site and which can reduce the cost of the reinforcing work and prevent the excessive injection.

Moreover, the method according to the present invetion makes the device to be maintained safely and makes the reinforced mortar layer surface to be even as well as makes the expandable injection plug to play the role of the support pin in the concrete wall even after the injection of the reinforcing agent is completed.

While particular embodiments of the present invention have been shown and modified, it will be apparent to those skilled in the art that minor changes and modifications may be made therein without departing from the true scope and spirit of the invention.

Claims

WHAT IS CLAIMED IS:

1. A device for reinforcing a concrete wall comprising a setting seat having a disc portion and a tube portion, said setting seat being adapted to be attached on a crack of the concrete wall, and a capsule assembly detachably set to said setting seat, said capsule assembly comprising an injection nozzle adapted to be engaged detachably with the tube portion of said setting seat, a bellows shaped capsule filled with the reinforcing agent and adapted to be engaged with the base portion of the injection nozzle, a coil spring for squeezing the bellows shaped capsule through the disc in order that the reinforcing agent in the capsule is injected into the crack of the concrete wall through the passage of the injection nozzle and the setting seat, a case accommodating the injection nozzle, the capsule and the coil spring, a front cap which is detachably connected to the front end of the case and into which the screw portion of the injection nozzle is inserted, and a rear cap which is detachably connected to the rear end of the case and to which the rear end of the coil spring is fixed.

2. A reinforcing device according to claim 1, wherein said rear cap has a hole through which a hollow rod is inserted, said hollow rod having a ring at the rear end thereof and a hole in the middle portion thereof, said ring being adapted to be used for pulling said hollow rod rearward so that the coil spring is compressed with the aid of a disc which is fixed to the front end of the hollow rod, and said hole being adapted to insert therethrough the cotter pin so as to maintain the hollow rod in the pulled state.

3. A method for reinforcing a concrete wall comprising attaching a setting seat on a crack of a concrete wall with the aid of an adhesive agent, setting a capsule assembly to said setting seat by connectingthe screw portion of the injection nozzle to the tube portion of the setting seat, said capsule assembly being adapted to squeeze the capsule, and squeezing the capsule so as to inject the reinforcing agent to the crack of the concrete wall through the passage of the injection nozzle and the setting seat.

4. A method according to claim 3, further comprising the steps of drilling a hole having a suitable diameter and a depth piercing into the concrete wall body to some extent through the mortar layer at a suitable place on the crack formed due to the parting of the mortar layer from the surface of the concrete wall body, cleaning said hole, inserting into said hole an expandable injection, plug having a base portion-and a front portion, said plug splitting into at least three portions at the end thereof, said portions each having a small hole in the middle portion thereof and a tapered opening at the front end thereof, fixing the expandable injection plug so as to expand in said hole by striking the pin into said tapered opening, and setting the capsule assembly to the base portion of said expandable injection plug.

5. A method according to claim 4, further comprising drilling a number of holes with suitable spacing on the crack formed due to the parting of the mortar layer from the surface of the concrete wall body, fixing the expandable injection plugs in said holes, setting capsule assemblies to said expandable injection plugs .and connecting the rings of said capsule assemblies with a string to maintain them in safe state.

6. A method according to claim 4, further comprising fixing said expandable injection plug in said hole formed in the concrete wall, inserting the screw portion of the adapter into the base portion of the expandable injection plug through the hole of a pressing plate so that the front surface of said pressing plate presses the mortar surface of the concrete wall, and setting the capsule assembly into the female thread of the adapter.