KR101434523B1 - Seismic Retrofitting of Concrete Structures by using Coating Fiber Mesh Grid and Inorganic Cementitious Matrix Composite - Google Patents

Abstract

The present invention relates to the maintenance and the seismic reinforcement of a concrete structure. The method for the maintenance and the seismic reinforcement of a concrete structure uses a fiber grid in which fibers intersect in the horizontal and vertical directions by using fixing members to form grid shapes and an inorganic cement matrix containing water-soluble acrylic resin and lime to ensure the reinforcing performance, ease of construction, and flame retardancy by using the fiber grid with enhanced adhesion and the inorganic cement matrix.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for repairing and reinforcing a concrete structure using an inorganic cement matrix and a coated fiber grid,

The present invention relates to repair and seismic reinforcement of concrete structures, and more particularly, to an improvement of seismic reinforcing ability by increasing ductility using a fibrous grid (coating treatment for improving adhesion) and inorganic cement matrix, And to a method of repairing and reinforcing a concrete structure using a fiber grid coated with inorganic cement matrix capable of forming flame retardancy with ease of construction.

Generally, in asphalt, not only traffic load and ground behavior but also chloride penetration to remove freezing, sea ice and icing causes vertical or horizontal deformation on the pavement surface, which causes cracking and breakage of asphalt.

Meanwhile, in order to reinforce cracked and broken asphalt as described above, the present applicant has proposed an asphalt reinforcement and an asphalt reinforcing method using it (Publication No. 10-2005-0102469).

The conventional asphalt reinforcement and the asphalt reinforcing method using the asphalt reinforcement are formed by forming a sanding layer on the upper side of the lattice net in which the glass fiber is crossed up and down and the asphalt emulsion is coated on the surface thereof, Is rolled in a roll, and is unrolled when the asphalt is reinforced, and then the film layer formed on the lower side is burned by using a flame.

However, in the conventional asphalt reinforcement, when the glass fiber is crossed up and down during the formation of the first lattice network and the surface is coated through the asphalt emulsion, the crossed glass fibers are loosened, There is a problem that it is not done.

In addition, the asphalt emulsion used as the coating layer is sensitive to the external environmental factors such as summer and winter temperatures, and is affected by the penetration degree during storage and construction. Asphalt emulsion which always maintains constant penetration is used Therefore, it has been pointed out that the workability and the storage property remarkably deteriorate.

In the case of the sanding layer, the fine silica sand is used, which causes the dust to be generated during the operation, which makes the working environment extremely poor, thereby posing a risk to the safety of the operator.

In addition, in the case of the film layer, the asphalt stiffener is prevented from sticking to each other in the rolling process (rolling) of the roll, but after the unrolling, it is burnt through the flame to act so that the coating layer of the lattice network can be easily attached to the asphalt base. If the thickness of the conventional film layer is reduced, the asphalt reinforcements stick to each other. If the thickness of the film layer is too thick, the flame does not burn well, resulting in poor workability and storage.

In order to solve these problems, the present applicant has proposed a glass fort reinforcement and an asphalt reinforcing method using the same (Patent No. 10-1077472).

The asphalt reinforcing method using the glass pult is formed by crossing the transverse direction glass fiber and the longitudinal direction glass fiber at intervals of 1.8 to 2.2 cm and in order to maintain the bonding force between the transverse direction glass fiber and the longitudinal direction glass fiber, The fiber is divided into first and second directional glass fibers and then intersected with each other when crossing with the lateral direction glass fibers. The first and second directions of the transverse direction glass fiber and the longitudinal direction glass fiber In order to increase the bonding force between the glass fibers, a glass fiber lattice network composed of fine glass fibers which are bonded in the form of wrapping the first and second directional glass fibers and the transverse direction glass fibers in the direction in which the first and second directional glass fibers extend ; A coating layer formed by impregnating the lattice glass fiber into an impregnation machine containing an asphalt emulsion; A silica sand layer formed on the mesh glass fiber; And a resin film layer formed on the lower side of the lattice glass fiber, the method comprising: a first step of heating the resin film layer of the glass-plus-pillar reinforcing material and burning the resin film layer, removing the resin film layer, and disposing the existing asphalt on the cut asphalt base; And a second step of packaging the asphalt on the upper side of the glass fountain reinforcement.

This method not only enhances the bonding force of the glass fiber lattice network but also improves work efficiency and workability by using different intrusions according to the seasons, thereby solving the problem in Publication No. 10-2005-0102469.

The above-mentioned Japanese Patent No. 10-1077472 uses a method of attaching the resin film layer to the asphalt base while burning the resin film layer on the lower side of the glass paste reinforcement.

That is, in the case of a reinforced concrete structure, moisture penetrates into the inside of the reinforced concrete structure. Although moisture can be reliably discharged to the outside quickly, corrosion of the reinforcing steel in the reinforced concrete structure and durability of the reinforced concrete structure can be attained. Since the layer is made of synthetic resin which is not permeable to water, the moisture collected inside is not discharged to the outside, thereby causing problems in the corrosion of the reinforced concrete structure and the durability due to the occurrence of the internal stress, so that it is applied to the reinforced concrete structure There was an inadequate problem to do so.

Also, in most of the reinforced concrete structures, stresses such as compression and tensile are generated due to the load. In the above-mentioned conventional techniques, there is a limit to the application of such reinforcement to stress.

That is, in the case of a reinforced concrete structure receiving an external force, a bending deformation occurs. However, in the prior art, there is a problem that it is difficult to apply to a reinforced concrete structure because the structure is not enough to reinforce the bending deformation.

In order to solve the above problems, the repair and seismic strengthening method of a concrete structure using the inorganic cement matrix and the coated fiber grid of the present invention may be performed by using a shotcrete mortar containing a mesh and a plurality of additives, The present invention also provides a method for repairing and reinforcing a concrete structure using a fibrous grid coated with a mineral cement matrix capable of being installed on a wet surface.

According to the present invention, calcium silicate grows between pores of a grid of fibrous webs attached to a reinforced concrete structure by an inorganic cement matrix, thereby improving the adhesion capacity and shortening the fixing length of the fibrous grid. The effect of improving the economical efficiency can be obtained.

Further, by forming an additional aluminum reinforcement to reduce the size of the bending moment, the reinforcement length can be shortened to enhance the reinforcement of the reinforced concrete structure and the reinforcing ability of the inorganic cement matrix.

In addition, it is possible to improve the efficiency and convenience of construction by using dry or wet type according to working conditions when spraying inorganic cement matrix.

In addition, the flame retardancy can be imparted by tempering the mesh-shaped lattice by forming an oxygen barrier film at a high temperature to prevent oxidation of the carbon fiber bundle during a fire.

In addition, it is a useful invention for further improving the flame retardancy by injecting an inorganic cement matrix, which is an additional fire protection layer, on the mesh.

1 is a perspective view showing a fiber grid according to the present invention;
2 is an enlarged view of part A of Fig.
3 is a state diagram showing a state in which a fixing member is formed in the construction method of the present invention.
4 is a state view showing a state in which an inorganic cement matrix is applied in the construction method of the present invention.
5 is a state view showing a state in which an aluminum reinforcing member for reinforcing a reinforcing concrete structure is formed.
Fig. 6 is an enlarged view showing a main part of Fig. 5; Fig.

Hereinafter, the method of the present invention will be described in detail with reference to the accompanying drawings.

The method of the present invention can improve the mechanical strength of the aged reinforced concrete structure due to deterioration or chemical corrosion by providing a coated fiber grid and an inorganic cement matrix on the reinforced concrete.

Before describing the method of the present invention, the structures used in the method will be described.

1. Fiber grid

The fibrous grid 10 in the present invention is formed in a lattice pattern by crossing the longitudinal fibers 11 extending in the longitudinal direction and the transverse fibers 12 extending in the transverse direction. The fibrous grid 10 may be made of any one of fibers extending in the longitudinal direction or in the transverse direction, and the fibers extending in the other direction may be formed of carbon fibers, All fibers can be formed of carbon fibers.

When the fiber grid 10 is formed of glass fibers and carbon fibers, the transverse fibers 12 made of carbon fibers are formed of first and second carbon fibers 12a and 12b as shown in FIGS. 1 and 2 The fibers are alternately arranged so as to be different from each other such that phase difference is generated between the upper and lower portions when crossing with the longitudinal fibers 11 made of glass fibers, and in the direction in which the transverse fibers 12 made of the carbon fibers extend It is possible to further form fine fiberglass 13 in the form of enclosing longitudinal fibers 11 made of glass fibers and transverse fibers 12 made of carbon fibers.

Further, amorphous silica (s) may be further formed on the surface of the fiber grid 10.

The fibrous grid 10 has 50 to 58.5 strands of carbon fiber having an elastic modulus of 240 KN / mm 2 and an ultimate tensile strength of 4,000 N / mm 2, and each strand has 1 × 1,600 to 3 × 1,600 tex It can be formed variously according to the required amount of reinforcement.

2. Mineral cement matrix

The inorganic cement matrix 20 comprises 63 wt% of aggregate having a particle size of 1 to 2.5 mm, 32 wt% of cement, 3.0 wt% of silica fume and pozzolan additive, and a polymer, plasticizer, defoamer, shrinkage additive, 0.0 >% < / RTI >

First, the cement may be various types of cement such as ordinary portland cement or quick-setting cement having improved curability, but it is preferable to use quick-speed cement which is special cement.

Next, the silica fume and pozzolan additives are added so as to promote early curing by promoting the strength development and hardening of the inorganic cement matrix after grouting.

Particularly, the pozzolan additive may be selected from among volcanic ash, acid clay, diatomaceous earth and fly ash.

Next, the power pack for increasing adhesion consists of polymer, plasticizer, defoamer, shrinkage additive, polypropylene fiber and reactive component.

First, the polymer uses a powder-modified powder-modified polymer to modify the cement. The powder-modified polymer has a glass transition temperature of 7 캜 and is transformed by heat generated by heat to form a rubber-like flexibility, thereby flexibly coping with changes in the concrete structure.

This flexibility prevents the deterioration of waterproof performance and permeability due to cracks in concrete structures.

Here, the glass transition temperature usually refers to a state transition occurring in a polymer substance. In the case of a low-molecular substance in a general solid state, a state transition from a solid state to a liquid state occurs when heat is applied. In the case of a solid state polymer, Is a phenomenon in which the material is softened like a rubber due to the phenomenon of falling out.

That is, in the present invention, by using the above-mentioned powder-modified polymer having a relatively low glass transition temperature, it is possible to flexibly cope with a change in crack or the like of the concrete structure as described above.

Particularly, in the present invention, it is used as any one material selected from vinyl acetate and vinyl versatate.

This is because the compatibility with the aluminate cement is obtained through a lot of experiments, and the aluminate cement can not be modified if the compatibility is poor.

On the other hand, a plasticizer is an organic material which is easily added to a thermoplastic plastic such as vinyl chloride / vinyl acetate to increase the thermoplasticity to facilitate molding at a high temperature. It improves heat resistance, cold resistance, flame resistance and electrical properties in addition to mixing and plasticity. The invention utilizes the sodium salt of a melamine formaldehyde condensate.

Next, the antifoaming agent is a powder antifoaming agent. The powder defoamer is used to reduce the amount of air generated when the one-pack type polymer cement mixture is blended, and the one-pack type polymer cement mixture is completed by mixing water with the above-described components.

Next, the contraction complementary uses to supplement the zooming and to simultaneously dry-axis reduces the shrinkage that occurs during drying.

The shrinkage enhancer uses polypropylene fiber fibers having a particle size of 6 to 12 mm. The polypropylene fiber fiber serves to adjust the plastic shrinkage cracking while increasing the fracture toughness and to reduce the drying shrinkage crack.

Such a polypropylene fiber can be used for a modified polymer having a high glass transition temperature or a powder modified polymer to improve the ability to recover when cracks or the like occur in a concrete structure.

In the present invention, a reactive component (RC) is added to the inorganic cement matrix 20 to further increase the adhesion between the mesh, which is a fibrous grid, and the wet shotcrete.

These reinforced concrete reaction components are mixed with lime and water-soluble acrylic resin in a weight ratio of 1: 1.

The lime can promote the growth of the calcium silicate contained in the cement in the space formed between the fibers of the fiber grid 10 and the fibers so as to improve the bonding force between the reinforcing concrete structure and the fiber grid and inorganic cement matrix And the above-mentioned water-soluble acrylic resin functions to compensate for the insufficient adhesion force of the fiber grid 10.

3. Reinforcement method

First, reinforcing method of reinforced concrete structure using fiber grid and mortar of the present invention,

(1) a surface treatment step in which the surface of a reinforced concrete structure is fluidically assembled,

A fiber grid fixing step of fixing the fiber grid using a fixing member,

And ③ inorganic cement matrix shotcrete work step which forms mineral cement matrix on the surface of reinforced concrete structure where fiber grid is fixed.

Details of the construction step will be described below.

First, the present invention summarizes the surface of a reinforced concrete structure for reinforcing work. (Surface Treatment Step)

The surface treatment step is performed to remove the deteriorated surface of the reinforced concrete and to maintain the flatness of the surface while removing foreign matter adhering to the surface.

Such a surface treatment step may employ various methods such as a wet sand spray method and a high pressure wash water spray method.

However, among the various methods listed above, in the case of high-pressure rinse water injection, the amount of water remaining on the surface of the reinforced concrete structure increases when the reinforced concrete structure is directly sprayed.

Generally, when reinforcement of a reinforced concrete structure is performed through a fibrous grid of a grid pattern, most of the fiber grid 10 is impregnated with epoxy to form an adhesive force to adhere to the surface of the reinforced concrete structure. In the reinforcement method, surface cleaning for removing foreign matter using high pressure washing water is extremely limited, and the deteriorated portion of the reinforced concrete structure is not smoothly cleaned.

Particularly, when the high-pressure washing water spraying method is used for a long time, the surface of the reinforced concrete structure becomes wet and the adhesive force is lowered. Also, the remaining water is not released to the outside and remains in the reinforced concrete structure for a longer time. It is inevitable to carry out a more restrictive operation.

However, since the fiber grid 10 is fixed by using the fixing member 30 when the fiber grid 10 is attached to the surface of the reinforced concrete structure as shown in FIG. 3 (fiber grid fixing step) as in FIG. 3, It is possible to fix the fiber grid 10 to the fiber grid 10 easily, and since the epoxy grid is not used for the fiber grid 10, the moisture present on the surface of the reinforced concrete structure is discharged to the outside.

On the other hand, the inorganic cement matrix 20 may be applied to the surface of the reinforced concrete structure having the surfaces formed by the above-described sand or high-pressure washing water spraying to further flatten the work.

The flattening operation is performed only when the surface of the reinforced concrete structure is not flat. At this time, it is preferable that the thickness of the inorganic cement matrix 20 during the flattening operation does not exceed 5 mm.

If the thickness of the inorganic cement matrix 20 is greater than the threshold value, it is difficult to fix the fiber grid 10 by the fixing member 30 and the reinforcing concrete structure and the fiber grid 10 There is a problem that the bonding force is lowered.

Here, the method of applying the inorganic cement matrix 20 to the surface of the reinforced concrete structure can be carried out by various methods such as spraying or using a plastered hand.

Next, the fiber grid fixing step is a step of fixing the fiber grid 10 using the fixing member 30 after the reinforcing concrete surface is arranged in the surface treatment step described above.

The fixing member 30 may be formed by a variety of methods such as a rivet, an anchor, an air nailer, or an electric nailer, but it is preferable to use an air nailer for the convenience of operation.

In particular, the fiber grids 10 of the present invention are formed in a generally plate-like shape in which the fibers are crossed in two directions to form a lattice pattern as described above. Such a fiber grid 10 is fixed The fixing member 30 is fixed to the outer peripheral edge of the reinforcing concrete structure when the reinforcing concrete member is fixed to the surface of the reinforced concrete structure through the member 30. [

At this time, the fixing member 30 is formed to have a fixing force by forming the fixing member 30 to a predetermined length starting from one end of the fixing member 30. In the present invention, the fixing member 30 ).

Also, when the area of the reinforced concrete structure to be repaired is large, when two fiber grids 10 are overlapped and fixed by using the fixing member 30, the overlapping length is 10 to 30 cm do.

Generally, it is well known that as the fixed length of the fiber grid 10 through the fixing member 30 becomes longer, the adhesive force and the reinforcing strength are improved. However, when the fixing member 30 has a longer length, The strength can be improved, but the workability and thus the cost of construction due to this increase, and also the cracks of the reinforced concrete structure can be caused by the plurality of fixing members 30. [

Even if the fixed length range of the fixing member 30 is reduced, even if the inorganic cement matrix 30 in the inorganic cement matrix grouting step (see FIG. 4), which is a downstream process, receives more tensile force or compressive force, It is possible to obtain an effect that the inorganic cement matrix 10 is not exposed to the outside of the inorganic cement matrix 30, that is, an excellent reinforcing property.

5, the growth of calcium silicate hardly occurs in the grouted photographs on the surface of the fiber grid 10 by using the general spray mortar. On the other hand, as shown in FIG. 6, the inorganic cement matrix 30), calcium silicate grows into the fiber grid 10.

This is because the calcium silicate contained in the cement is promoted between the lattice grooves 14 of the fiber grid 10 by the lime as the reactive component of the reinforcing concrete of the power pack contained in the inorganic cement matrix 30, The fixing force of the fiber grid 10 and the inorganic cement matrix 30 becomes extremely high. Therefore, even if the fixing length is made shorter than the conventional fixing strength, the sufficient reinforcing strength can be obtained.

In particular, in the step of grouting the inorganic cement matrix, it is preferable that the inorganic cement matrix 30 does not exceed 10 cm.

This is because if the inorganic cement matrix 30 is grouted in too much amount, the inorganic cement matrix 30 will be dropped due to its own weight before the inorganic cement matrix 30 is cured due to deterioration of the adhesion of the fiber grid 10 This is because the phenomenon may occur.

On the other hand, in the case of a general reinforced concrete structure, flexural deformation due to external pressure (tensile force, compressive force) occurs at a position where the load is supported such as a column or a beam.

As shown in FIGS. 5 to 6, the reinforcing concrete structure self-load or soil or other structures (for example, a portion where the moment becomes zero) Dimensional parabolic shape protruding downward due to a load formed by the first and second electrodes.

Such a bending curve is formed in proportion to the self weight of the reinforced concrete structure, the magnitude of the applied load, or the stiffness of the reinforced concrete structure.

In the present invention, the aluminum stiffener 40 may be additionally formed to prevent flexural deformation of the reinforced concrete structure and enhance reinforcement through the fiber grid 10 by arbitrarily adjusting the flexural curve.

The aluminum stiffener 40 generates a bending curve in anticipation of the bending deformation of the reinforced concrete structure installed on the actual site using a stress analysis program and receives the load, And then joined using an auxiliary fixing member 41 such as a normal bolt or air liner.

Since the position of the aluminum reinforcing member 40 is determined based on the bending curve of the reinforced concrete structure, it is possible to prevent the flexural deformation of the reinforced concrete structure at the optimum position.

In the present invention, the fiber grid fixing step and the inorganic cement matrix grouting step may be repeatedly performed one to three times to further improve the reinforcing property. At this time, the fiber grid 10 and the inorganic cement matrix 30 ) Should be formed so that the total thickness does not exceed 27 to 30 cm.

When the thickness is less than the thickness, the effect of the reinforcement is deteriorated. When the thickness is exceeded, the increased effect is not obtained.

In the meantime, the inorganic cement matrix grouting step in the present invention can utilize the inorganic cement matrix 40 as dry or wet depending on whether equipment for grouting can be installed and the distance between the equipment and the work space.

When the inorganic cement matrix 40 is used as a wet type, the inorganic cement matrix 40 and water may be mixed with a mixer, sprayed through a nozzle, and grouting may be performed.

This wet type method can reduce the material cost and work time by reducing the amount of rebound when the inorganic cement matrix 40 is sprayed on the surface of the reinforced concrete structure.

However, when the apparatus can not be installed by working in a narrow space, the inorganic cement matrix 40 in the form of a powder is moved to the nozzle using compressed air, and water is separately sucked into the nozzle The work can be performed in a state in which it is installed in the nozzle so as to be sprayed like the inorganic cement matrix 40.

Of course, in the case of the dry type, there is a disadvantage that the amount of rebound is large, which causes a delay in material cost and working time.

However, when the wet type inorganic cement matrix 40 is formed in advance in the apparatus using the dry type method, the inorganic cement matrix 40 is hardened in the channel in which the inorganic cement matrix 40 moves, It is possible to prevent the deterioration of the efficiency of the display device.

While the present invention has been described in connection with certain exemplary embodiments, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims.

10: Fiber Grid
11: Longitudinal fibers
12: transverse fiber 12a: first carbon fiber 12b: second carbon fiber
13: fine fiber
14: grid home
20: inorganic cement matrix
30: Fixing member
40: Aluminum stiffener
41: auxiliary fixing member

Claims (11)

A surface treatment step of arranging the surface of the reinforced concrete structure to be repaired by spraying sand spray or high pressure wash water spray or sand and high pressure wash water;
In the surface treatment step, fibers are crossed in a longitudinal direction and a transverse direction using a fixing member on the surface of the reinforced concrete structure where the flattening operation is completed, thereby forming a lattice shape. On the surface of the reinforcing concrete structure, fibers for fixing the fibrous grid pretreated with amorphous silica Grid fixing step;
And an inorganic cement matrix grouting step of grouting the inorganic cement matrix at a thickness of 2 to 3 cm on the surface of the reinforced concrete structure provided with the fiber grid by spraying after the fiber grid fixing step, Repair and Seismic Retrofit of Concrete Structures Using Matrix and Coated Fiber Grid.
The method according to claim 1, wherein the inorganic cement matrix is further characterized in that the surface of the reinforced concrete structure is subjected to surface treatment by sanding the inorganic cement matrix after finishing the surface of the reinforced concrete structure with the high- Repair and Seismic Retrofit of Concrete Structures Using Fiber Grid.
The fiber grid according to claim 1, wherein the fiber grid in the fiber grid fixing step is formed of glass fiber and the fiber extending in the other direction is formed of carbon fiber, Repair and seismic retrofit of concrete structures using inorganic cement matrix and coated fiber grid characterized by forming all kinds of fiber in longitudinal and transverse directions by carbon fiber.
delete The fiber grid according to claim 1, wherein the fibrous grid formed by intersecting fibers in the longitudinal and transverse directions in the fiber grid fixing step has a tensile strength of 240 KN / mm < 2 > and an ultimate tensile strength of 4,000 N / And each strand is characterized by a different amount of reinforcement required from 1 x 1,600 tex to 3 x 1,600 tex Repair and Seismic Retrofit of Concrete Structures Using Inorganic Cement Matrix and Coated Fiber Grid .
The method as claimed in claim 1, wherein the fixation member fixing length for fixing the fiber grid in the fiber grid fixing step is 10 to 30 cm, and the length of the fixing member is 10 to 30 cm when the fiber grid is stacked and fixed Repair and Seismic Retrofit of Concrete Structures Using Mineral Cement Matrix and Coated Fiber Grid.
The fiber grid according to claim 1, wherein, after fixing the fibrous grid through the fixing member in the fiber grid fixing step, a fibrous grid between the fixing member and the fixing member to prevent warping of the reinforced concrete structure when a load is applied to the reinforced concrete structure Repair and seismic retrofit of concrete structures using inorganic cement matrix and coated fiber grid, characterized by further forming of aluminum reinforcement in installed reinforced concrete structures.
2. The method according to claim 1, wherein the fiber grid fixing step and the inorganic cement matrix grouting step are repeated one to three times, and the inorganic cement matrix is applied in a thickness of 9 to 10 cm in the inorganic cement matrix grouting step Repair and Seismic Retrofit of Concrete Structures Using Inorganic Cement Matrix and Coated Fiber Grid.
The method according to claim 1, wherein in the step of grouting the inorganic cement matrix, the inorganic cement matrix comprises 63 wt% of aggregate having a particle size of 1 to 2.5 mm, 32 wt% of cement, 3.0 wt% of silica fume and pozzolan additive, Repair and seismic retrofitting of concrete structures using inorganic cement matrix and fiber grid coated with 2.0% by weight of a power pack comprising plasticizer, defoamer, shrinkage additive and polypropylene fiber.
10. The method of claim 9, wherein the power pack comprises a 1: 1 weight ratio of lime and water-soluble acrylic resin as reactive components of the reinforcing concrete, and the repair and seismic resistance of the concrete structure using the inorganic fiber cement matrix and the coated fiber grid Reinforcement method.
The method according to claim 1, wherein when the distance between the reinforcing concrete structure for reinforcing the inorganic cement matrix grouting and the equipment for spraying the inorganic cement matrix is close to the inorganic cement matrix, Based cement matrix,
When the distance between the reinforced concrete structure for reinforcement work and the equipment for spraying the inorganic cement matrix is long, powdered inorganic cement matrix and water are separately supplied, and powder is sprayed from the tip of the nozzle for spraying inorganic cement matrix Repair and seismic retrofit of concrete structures using inorganic cement matrix and fiber grid coated with inorganic cement matrix and water, sprayed on reinforced concrete structure and grouting.

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