JP2020190102A - Crack repair method and crack repair spray - Google Patents

Abstract

To provide a crack repair method and a crack repair spray capable of easily and inexpensively repairing a crack without being limited by the direction and shape of a repair object.SOLUTION: A crack repair method for injecting a repair agent 2 containing sodium silicate as a main component into a crack generated in a cement cured body, comprising the steps of: jetting a repairing agent 2 stored in a repairing spray 3 together with a compressed gas 4 from a jetting nozzle 35 in a state in which the tip of a jetting nozzle 35 of the repairing spray 3 is inserted into a crack 11; and sprinkling water around the crack.SELECTED DRAWING: Figure 2

Description

The present invention is a crack repair method and a crack repair spray.

The concrete structure may be cracked due to aged deterioration or the action of a large external force. If rainwater or the like permeates the cracks generated in the concrete structure, the deterioration of the concrete structure will accelerate. Therefore, it is desirable to promptly repair cracks generated in the concrete structure.

As a method for repairing cracks, a method of injecting a resin-based adhesive such as an epoxy resin, a urethane-based resin, an acrylic resin, or the like into the cracks is known. However, the effect of the resin-based adhesive may decrease due to aged deterioration. Therefore, Patent Document 1 discloses a repair method in which a repair agent containing sodium silicate as a main component is applied to the surface of a concrete member and permeated into cracks. According to this repair method, the repair agent that has penetrated the crack reacts with calcium in the concrete and gels, so that the crack can be closed. Since the repair agent reacts with concrete and gels, the blocking effect is not reduced by the deterioration of the repair agent.

When the cracks generated in the concrete were fine (when the width of the cracks was small), it was difficult to infiltrate the repair agent. Therefore, Patent Document 2 discloses, as a method of repairing a concrete member in which fine cracks have occurred, a method of applying a repairing agent to the surface of the concrete member including a heated cracked portion and then cooling the concrete member. In this repair method, the repair agent is infiltrated into the inner part of the crack by utilizing the pressure reduction in the crack during cooling.

Japanese Unexamined Patent Publication No. 2004-323333 Japanese Unexamined Patent Publication No. 2019-027204

In the repair method of Patent Document 2, it takes time and effort to heat the concrete member. In addition, a device for heating the cracked portion of the concrete member is required. Further, when repairing a crack generated on a wall surface or the like, the repair agent could not be permeated in the lateral direction.

From this point of view, the present invention proposes a crack repair method and a crack repair spray capable of repairing cracks easily and inexpensively without being limited to the orientation and shape of the object to be repaired. Make it an issue.

In order to solve the above problems, the crack repair method of the present invention is to inject a repair agent containing sodium silicate as a main component into cracks formed in a hardened cement product. The repair agent is stored in the repair spray together with the compressed gas, and is sprayed from the nozzle with the tip of the nozzle of the repair spray inserted into the crack or in contact with the surface of the crack. After spraying the repair agent, water is sprinkled around the cracks.

According to such a crack repair method, since the repair agent is injected into the crack by using the compressed gas, the repair agent can be permeated deep into the crack even when the repair agent is permeated sideways or upward. it can. The repair agent that has penetrated into the cracks closes the cracks by reacting with the calcium content of the hardened cement (concrete, mortar, cement paste, etc.) and gelling. Moreover, the construction can be carried out without requiring a special device such as a heating device.

Further, the crack repair spray of the present invention includes a repair agent containing sodium silicate as a main component, a spray can in which the repair agent and the compressed gas are stored, an actuator attached to the head of the spray can, and the above. A check valve provided at the attachment portion between the actuator and the spray can, a liquid feeding tube for guiding the repair agent to the check valve in the spray can, and a ejection nozzle attached to the actuator. I have. The liquid feeding tube has a length from at least the check valve to the bottom of the spray can, and a stirring ball is attached to the tip thereof.

According to such a crack repair spray, a repair agent containing sodium silicate as a main component can be sprayed into the crack to allow the repair agent to penetrate deep into the crack. In addition, since the stirring ball is attached to the tip of the liquid feeding tube, the tip of the liquid feeding tube is always under the can (repair agent) depending on the weight of the stirring ball even when the direction of the spray can is changed. Can be located inside). Therefore, even when the spray can is turned upside down (upside down), the repair agent can be injected into the crack.

According to the crack repair method and the crack repair spray of the present invention, it is possible to repair cracks easily and inexpensively without being limited to the orientation and shape of the object to be repaired.

It is a perspective view which shows the outline of such a crack repair method of embodiment of this invention. It is sectional drawing which shows the crack repair spray used for the crack repair. It is sectional drawing which shows the use situation of the crack repair spray.

In the present embodiment, as shown in FIG. 1, a case of repairing a crack 11 generated in a wall (cement hardened body) 1 of a concrete structure will be described. The crack 11 is repaired by injecting the repair agent 2 containing sodium silicate as a main component into the crack.

The repair agent 2 is injected into the cracks by using the repair spray (crack repair spray) 3. As shown in FIG. 2, the repair spray 3 includes a spray can 31 in which the repair agent 2 and the compressed gas 4 are stored, an actuator 32 attached to the head of the spray can 31, and the actuator 32 and the spray can 31. It includes a check valve 33 provided in the mounting portion, a liquid feeding tube 34 that guides the repair agent 2 to the check valve 33 in the spray can 31, and a ejection nozzle 35 attached to the actuator 32.

The material constituting the repair agent 2 is not limited as long as it contains sodium silicate as a main component, but in the present embodiment, at least two or more kinds of alkali metal compounds among sodium silicate, potassium silicate and lithium silicate are used. Use a mixture of. The specific gravity of the repair agent 2 is not limited, but is about 1.2 to 1.3. Further, as the compressed gas 4, liquefied petroleum gas (LPG or LP gas) is used. The type of the compressed gas 4 is not limited, and for example, dimethyl ether (DME) may be used.

The spray can 31 is a container for storing the repair agent 2 and the compressed gas 4. The spray can 31 is made of a so-called aluminum can made of an aluminum alloy. The material constituting the spray can 31 is not limited as long as it has sufficient strength against the content (compressed gas 4), and may be, for example, a steel can. The spray can 31 has a cylindrical shape with a height of about 15 mm and an outer diameter of about 5 cm, and the bottom of the spray can 31 is recessed upward and in a bowl shape. Further, the upper portion of the spray can 31 (the upper portion of the body portion having a cylindrical shape) is inclined so that the diameter decreases toward the top, and the upper end portion is shielded by the lid plate 37. Further, a through hole for inserting the valve rod 38 of the check valve 33 is formed in the central portion of the lid plate 37. The shape of the spray can 31 is not limited, and for example, a recess at the bottom and an inclined portion at the top do not necessarily have to be formed.

The actuator 32 serves as a button for opening the check valve 33 and also functions as a liquid feeding path for injecting the repair agent 2. The actuator 32 is attached to a portion of the check valve 33 that protrudes from the lid plate 37 on the upper side of the lid plate 37. A ejection nozzle 35 is attached to the actuator 32. The actuator 32 guides the repair agent 2 supplied from the spray can 31 to the ejection nozzle 35 via the valve rod 38. The actuator 32 is removable from the valve stem 38. When the repair spray 3 is not in use, the actuator 32 may be removed from the valve stem 38 and a cap (not shown) may be attached to the head of the repair spray 3.

The ejection nozzle 35 is composed of a metal tube having an outer diameter of 1 mm. Since an aqueous solution having excellent permeability is used as the repair agent 2, even a ejection nozzle 35 having an outer diameter of 1 mm is unlikely to be clogged, and even fine cracks can be repaired. The ejection nozzle 35 is removable from the actuator 32 and can be cleaned (washed with water) after use. The material constituting the ejection nozzle 35 is not limited. Further, the length of the ejection nozzle 35 may be appropriately determined. The outer diameter of the ejection nozzle 35 is preferably 2 mm or less.

The check valve 33 shields the opening of the spray can 31 to prevent the contents (repair agent 2 and compressed gas 4) of the spray can 31 from flowing out and impurities from flowing into the spray can 31 from the outside. , It functions as a flow path for injecting the repair agent 2 when the valve rod 38 is opened by operating the valve rod 38. The check valve 33 is attached to the inner surface (the surface facing the inside of the spray can 31) of the lid plate 37 of the spray can 31. The valve rod 38 extending from the upper part of the check valve 33 (contact portion with the lid plate 37) penetrates the lid plate 37. The valve stem 38 is made of a tubular member. The check valve 33 is opened by pushing the valve stem 38 via the actuator 32. When the check valve 33 opens, the repair agent 2 is supplied to the actuator 32 via the valve stem 38 by the pressure of the compressed gas 4.

The liquid feeding tube 34 guides the contents (repair agent 2) of the spray can 31 to the check valve 33. One end of the liquid feeding tube 34 is connected to the check valve 33, and the stirring ball 36 is attached to the other end. The liquid feed tube 34 has a length from at least the check valve 33 to the bottom of the spray can 31. The liquid feeding tube 34 is made of a flexible soft material (for example, polyvinyl chloride or the like), and is bent by the weight of the stirring ball 36. The liquid feeding tube 34 has the strength to secure an inner space for feeding the repair agent 2 even when the liquid feeding tube 34 is bent.

The stirring ball 36 stirs the contents (repair agent 2) by moving inside the spray can 31. The stirring ball 36 has a spherical shape. The stirring ball 36 is formed with a through hole into which the liquid feeding tube 34 can be inserted. The stirring ball 36 is adhered to the liquid feeding tube 34 with the liquid feeding tube 34 inserted in the through hole. The method of fixing the stirring ball 36 to the liquid feeding tube 34 is not limited. Further, the material constituting the stirring ball 36 is not limited, and for example, glass or metal may be used. In addition to the stirring ball 36 attached to the liquid feeding tube 34, another stirring ball 36 may be arranged in the spray can 31. The number and shape of the stirring balls 36 are not limited, and may be appropriately determined.

Next, a crack repair method using the repair spray 3 will be described.
When repairing the crack 11, as shown in FIG. 1, first, the tip of the ejection nozzle 35 is inserted into the crack 11. If the width of the crack 11 is too small to insert the ejection nozzle 35 (for example, the width of the crack is 1 mm or less), use a tool having a fine tip for the crack 11 (for example, an awl or a drill). A punch hole 12 having an inner diameter of 1 mm or more may be formed, and the ejection nozzle 35 may be inserted into the punch hole 12. At this time, the distance between the punch holes 12 is, for example, about 50 mm. If the crack penetrates the wall (hardened cement) 1, the cracked part on the back surface of the concrete member (the surface opposite to the surface on the repair spray 3 side) is covered with a curing tape or a removable sealing material. The outflow of the repair agent 2 is prevented by sealing.

After inserting the ejection nozzle 35 into the crack 11, the check valve 33 is opened by pushing the actuator 32, and the repair agent 2 is injected into the crack 11 via the actuator 32 and the ejection nozzle 35. The repair agent 2 ejected from the ejection nozzle 35 permeates vertically and horizontally along the crack 11. The repair agent 2 is injected until the repair agent 2 exudes onto the surface of the crack 11 in a predetermined range around the ejection nozzle 35. The repair agent 2 is injected along the crack 11 at intervals of about 50 mm. When the crack 11 is formed in the vertical direction, the repair agent 2 is injected while sequentially moving upward from the lower part of the crack 11. The interval (interval between the punch holes 12) when the repair agent 2 is injected is not limited.

After injecting the repair agent 2 into the crack 11, the repair agent 2 is dried for 1 hour to 2 hours or more, preferably from 1 hour to 4 hours. The drying time of the repair agent 2 may be appropriately determined depending on the season, temperature, humidity, etc. at the time of construction. After the repair agent 2 is dried, water is sprinkled around the crack 11. Watering is performed to the extent that the surface of the concrete member is moistened by using a sprayer or the like. Watering and drying shall be repeated twice or more. The number of times of watering is not limited, and may be, for example, once or three or more times.

After watering, the surface of the crack 11 is washed and cleaned with water. Cleaning is performed until the stickiness caused by the repair agent 2 exuded on the concrete surface disappears. If a detergent is used to clean the concrete members, use a neutral detergent and wash away the detergent sufficiently. The crack 11 is cleaned and water is sprinkled on the crack 11 so that water or the like is not directly press-fitted into the crack.

The repair agent 2 injected into the crack 11 reacts with the calcium content of the concrete facing the crack 11 and gels. When the repair agent 2 gels, the crack 11 is closed, so that water and deterioration factors cannot enter the inside of the concrete member (wall 1), and the inside of the crack 11 can be protected. Further, by injecting the alkaline repair agent 2, corrosion of reinforcing bars and the like in the concrete (wall 1) can be suppressed.

Further, by sprinkling water around the crack 11 into which the repair agent 2 is injected, the reaction between the calcium content of the concrete and sodium silicate is promoted, and the waterproof function and the water blocking effect are improved. That is, by supplying water, the repair agent 2 is diluted, the specific gravity is lowered, and it becomes easy to permeate into the concrete, and the calcium content in the concrete is easily eluted, so that the reaction is promoted.

Since the stirring ball 36 is attached to the tip of the liquid feeding tube 34, the tip of the liquid feeding tube 34 is on the lower side even if the spray can 31 is turned upside down (actuator 32 is on the lower side) as shown in FIG. To position. Therefore, since the state in which the tip of the liquid feeding tube 34 (the suction port of the repair agent 7) is arranged in the repair agent 2 is maintained, the repair agent 2 can be sprayed even when the spray can 31 is turned upside down. ..

The repair of cracks does not require the use of special equipment or tools, and is completed only by spraying from the repair spray 3, so that the work is simple. Moreover, since no special technique is required, the repair effect is not uneven depending on the operator. Further, since the repair spray 3 is small with a height of about 15 cm to 20 cm and an outer diameter of about 4 to 6 cm, it can be stored in a pocket or the like and is easy to carry. In addition, since it is easy to use, staff other than workers can easily carry out repair work when inspecting the structure.

Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and each of the above-mentioned components can be appropriately modified without departing from the spirit of the present invention.
For example, in the above embodiment, the repair agent 2 is injected with the ejection nozzle 35 inserted into the crack 11, but the ejection nozzle 35 does not necessarily have to be inserted into the crack 11. For example, the repair agent 2 may be press-fitted into the crack 11 by injecting the repair agent 2 in a state of being in contact with the surface of the crack 11 of the ejection nozzle 35. Further, even if the repair agent 2 is press-fitted into the crack 11 by inserting the ejection nozzle 35 into the curing tape and injecting the repair agent 2 with the surface of the crack 11 covered with the curing tape or the like. Good.
Further, the punch hole 12 may be formed even when the crack width is large.

After the injection of the repair agent 2 into the crack 11 and watering are completed, the surface of the crack 11 may be repaired using a safe repair stick (manufactured by Sumitomo Osaka Cement Co., Ltd.). The safe repair stick is rubbed against the surface of the crack 11 in a wet state by rubbing it in a direction perpendicular to the crack 11, and then dried.

In the above embodiment, the case where the crack 11 generated in the concrete wall (wall 1) is repaired by the repair agent 2 has been described, but the repair target is limited as long as it is composed of a cement-based hardened material. is not. For example, it may be used for repairing mortar, cement paste and the like. Further, the object to be repaired is not limited to the wall 1, and may be used for repairing, for example, a floor board, a bridge, a tunnel lining, or the like. Further, the repair spray 3 of the present embodiment may be used for repairing the crack 11 generated in the tile.

1 wall (hardened cement)
11 Cracks 12 Punch holes 2 Repair agent 3 Repair spray (crack repair spray)
31 Spray can 32 Actuator 33 Check valve 34 Liquid feed tube 35 Discharge nozzle 36 Stirring ball 37 Lid plate 38 Valve rod 4 Compressed gas

Claims (2)

It is a crack repair method in which a repair agent containing sodium silicate as a main component is injected into cracks generated in a hardened cement product.
The step of injecting the repair agent stored together with the compressed gas in the repair spray from the nozzle with the tip of the nozzle of the repair spray inserted into the crack or in contact with the surface of the crack.
A method for repairing cracks, which comprises a step of sprinkling water around the cracks. A repair agent containing sodium silicate as the main component,
A spray can in which the repair agent and compressed gas are stored, and
The actuator attached to the head of the spray can and
A check valve provided at the attachment portion between the actuator and the spray can,
A liquid feeding tube that guides the repair agent to the check valve in the spray can, and
A crack repair spray comprising a ejection nozzle attached to the actuator.
The liquid feeding tube has a length from at least the check valve to the bottom of the spray can, and is characterized in that a stirring ball is attached to the tip of the spray can for repairing cracks.

Images