KR20000067421A - Fiber-Reinforced Epoxy Panel And Process For Preparing Thereof - Google Patents

Abstract

PURPOSE: An epoxy resin panel for fiber reinforcement and a manufacturing method thereof are provided to improve the tension strength and the bending strength by mixing glass fiber, carbon fiber, kevlar fiber, aramid and fiber mesh into epoxy resin mortar. CONSTITUTION: A method for manufacturing an epoxy resin panel for fiber reinforcement includes a step of piling up at least three fiber meshes on a stripper(20) inside a mold(10), a step of pouring mixture of resin mortar and reinforced fiber material, which are mixed in a prescribed ratio, on the piled fiber meshes, a step of vibrating a mold after pouring and compressing and molding in the pressure of 1000kg after plastically heating in infrared rays of 60 degrees for at least 30 minutes, a step of being plastic in 80 degrees for 3 hours and removing the mold, and a step of curing in the temperature of 25 to 30 degrees for 3 days.

Description

Fiber-reinforced epoxy resin panel and its manufacturing method {Fiber-Reinforced Epoxy Panel And Process For Preparing Thereof}

The present invention relates to a fiber-reinforced epoxy resin panel used to repair and reinforce various concrete structures, or to reinforce the bottom surface of a container box, and a method of manufacturing the same. The present invention relates to a fiber-reinforced epoxy resin panel and a method of manufacturing the fiber, kevlar fiber, aramid, and fiber mesh, which improve overall characteristics such as tensile strength and flexural strength.

At present, there are various reinforcing methods such as steel plate adhesive injection method, prestressing method, cross-section increase method, and member extension method.

Double steel plate injection injection method is a reinforcement method adopted for bending reinforcement and shear reinforcement when lack of bending resistance of bridge due to lack of rebar and lack of shear resistance of alternating and pier. It is a reinforcement method for the combination of shortage or lack of prestress and reinforcement by concrete pouring.In addition, the increase of cross section and extension of members are used as reinforcement methods due to lack of concrete section and lack of reinforcement. There is a situation.

Among the various reinforcement methods described above, the steel sheet adhesive injection method, which is the most widely used reinforcement method, improves the strength by integrating steel sheets with epoxy resin on the concrete surface of the concrete structure, in particular, the tension side surface, thereby integrating the pre-installed structure and the steel sheet. In other words, this means that the steel plate is bonded to the tension-side surface of the reinforced concrete member in the same way as the reinforced concrete and reinforced concrete structure of the reinforced concrete structure, and the shear force is secured by the adhesive force to secure the pre-installed reinforced concrete member and steel material. It is possible to achieve the desired purpose as a reinforcing material by integrating the steel sheet so that the steel sheet can function as part of the tensile reinforcing bar.

However, the above-described steel plate injection injection method requires continuous consideration to ensure that the adhesion and fixation performance of the steel plate and concrete bonded to the concrete surface of the tension side of the structure is sufficiently achieved and maintained, and exposed to the marine environment due to the characteristics of the structure. For the structure, there is a problem in that corrosion of the steel sheet or durability of the adhesive occurs, so that the actual repair and reinforcing effect can not be expected, and the weight of the steel plate itself is high, thereby increasing the load on the structure. In addition, the steel sheet adhesive injection method has a problem that inevitably increase the cost of construction because it requires a lot of work time and work people to be bonded to the bottom of the structure after cutting the iron plate to a certain size.

In addition to the steel plate adhesive injection method, the FRP panel adhesive injection method is also used to solve the problem of corrosion of the steel sheet, but this has a problem in that the strength of the FRP material is very weak and only serves as a kind of cover.

On the other hand, it was developed for the purpose of improving this point, "Epoxy resin panel for concrete structure reinforcement and its manufacturing method" and the same applicant filed by the same applicant (Patent No. 174,161) and Japanese Patent Application Laid-Open No. 4 -67946, "Composite Panels of Thermosetting Resins".

However, since the panels disclosed in the prior art all use metal wires as core materials, corrosion of the metal wires over long periods of time results in a weakening of the bond between the core wires and the resin mortar, resulting in cracking and peeling of the panels. , Weather resistance against climatic conditions such as temperature and humidity, and chemical resistance against hydrochloric acid, sulfuric acid, sodium hydroxide, etc. are weak. In particular, physical properties such as tensile strength and compressive strength are weakened by weakening the bond strength between core material and mortar. There is a deterioration defect.

Accordingly, an object of the present invention is to solve the above problems, and by molding a resin mortar mixture made by mixing a fiber mortar with resin mortar on each fiber mesh layered in multiple layers in the mold, And to provide an epoxy resin panel for fiber reinforcement which has increased mechanical strength, weather resistance and chemical resistance, and has excellent repair and reinforcement.

In order to achieve the above object, a method for manufacturing a fiber-reinforced epoxy resin panel of the present invention is a method of manufacturing a panel while applying a release agent to the inside of the mold of claim 1, wherein at least three or more fiber mesh is laminated on the release agent And pouring a mixture of the resin mortar and the reinforcing fiber material mixed at a predetermined ratio onto each layer of the laminated mesh, and applying vibration to the entire mold after casting, and thermally baking for 30 minutes under an infrared ray of 60 ° C. After the compression molding with a pressing force of 1000kg, and after the compression molding after firing at 80 ℃ for 3 hours, and demolding, the step of curing for 3 days while maintaining a temperature of 25 ~ 30 ℃ characterized in that it comprises do.

The mixed resin mortar is composed of epoxy resin (22.1% by weight), cement (1.4% by weight), silica (76.4% by weight), reinforcing fiber material (0.1% by weight), and the reinforcing fiber material is glass fiber, carbon fiber, It is characterized in that it is any one selected from aramid and Kevlar fiber.

Any one of the fiber mesh is characterized in that it further comprises the step of impregnating an epoxy resin.

In addition, the epoxy resin panel for reinforcing fibers of the present invention for achieving the above object is a reinforcing panel formed by the mold of claim 4, comprising a release agent applied to the bottom of the mold and at least three or more layers on the release agent One fiber mesh unit and a mixture of a reinforcing fiber material and a resin mortar mixed in a proportion above the layered fiber mesh are poured to be integrated with the fiber meshes by vibration, thermal plasticity, compression molding, demolding and curing. It characterized in that it comprises one resin mixing mortar portion.

The fiber reinforced resin panel obtained by the manufacturing method of claim 1 and the fiber reinforced resin panel having the structure of claim 4 are used in various repair and reinforcement works.

Repair works include ① repair of cracked parts of various concrete structures, ② repair of deteriorated concrete structures, ③ repair of damaged concrete structures, ④ protection of the surface of concrete structures subjected to salt, seawater, sewage, freezing and chemical action, and It is waterproof, ⑤ durability improvement, repair of concrete structure that needs to extend service life, ⑥ concrete structure requiring waterproofing and corrosion protection.

In addition, reinforcement work ① restore the flexural load capacity of concrete structures with deterioration, defect and damage. (2) Reinforce the load in the bending member of the section of the superstructure of the bridge and the section of the moment where the wheels of the vehicle do not directly touch. ③ Reinforcing port structure of slabs and walls of underground box structures such as subways and cavities. ④ Reinforcement of tunnel lining. ⑤ Reinforcement of slabs and walls of water and sewage treatment facilities. ⑥ Reinforcement of earth structures such as retaining walls, ⑦ Pier edge Reinforcement and reinforcement of vehicle bumps, ⑧ reinforcement of container box loading floor.

1 (A) to (F) is a cross-sectional view showing the manufacturing process of the fiber-reinforced epoxy resin panel according to the present invention,

Figure 2 is a cross-sectional view of the fiber reinforced epoxy resin panel according to the present invention,

Figure 3 is a cross-sectional view showing the construction state of the fiber-reinforced epoxy resin panel according to the present invention,

Figure 4A is a plan view of a corner casting member made to be suitable for use as a fiber reinforcement epoxy resin panel according to the present invention as a corner support reinforcement plate of the container box, Figure 4B is a side view, Figure 4C shows a construction state, respectively will be.

* Description of the symbols for the main parts of the drawings *

1: epoxy resin panel for fiber reinforcement

10: production mold 20: release agent

30a ~ 30c: Fiber Mesh 40: Epoxy Resin

50: mixed mortar 80: concrete structure

84: anchor bolt 90, 90a: epoxy adhesive

Hereinafter, a manufacturing example of the fiber reinforced epoxy resin panel according to the present invention will be described in detail with reference to the accompanying drawings.

1 (A) to (F) is a cross-sectional view showing the manufacturing process of the fiber-reinforced epoxy resin panel according to the present invention, Figure 2 is a cross-sectional view of the fiber-reinforced epoxy resin panel according to the present invention.

(A) process

After manufacturing the rectangular mold 10 having a predetermined dimension (width X length X thickness (height) (unit: mm)), dust such as foreign matter adhered to the inside is cleaned cleanly. In addition, the mold 10 is used again after removal of foreign matters after the panel manufacturing is completed. Dimensions of the mold 10 can be produced in any size, depending on the application, generally 1000 X 1,000 X 11 (mm), 800 X 1500 X 11 (mm) and / or 1000 X 500 X 11 (mm) Made with dimensions. The mold 10 is preferably formed of a metal material for durability.

(B) process

The mold 10 is uniformly applied to the entire inner surface of the mold 10 by using a general release agent 20.

(C) process

The first fiber mesh 30a having a scale of a predetermined size is installed above the release agent 20 in the mold 10. The first fiber mesh 30a is previously cut as a size that can be installed into the mold 10. In addition, an epoxy resin 40 is added to the first fiber mesh 30a so as to be impregnated with the entire first fiber mesh 30a. The use of the epoxy resin 40 is to improve the strength, it is preferable to use those having the following physical properties prepared by the present inventors.

Adhesive Viscosity: Below 380 mPaS (380 cP)

Gel Time: around 15 minutes

Compressive Strength: More than 1,000 kg / ㎠

Tensile Strength: More than 500 kg / ㎠

Flexural Strength: 800 kg / ㎠

Shear Strength: 200kg / ㎠ or more

Adhesion Strength: Over 130 kg / ㎠

Tensile Failure Strain: 0.02 or more

Linear expansion coefficient: (1.0 ~ 2.0) X10-5 ㎝ / ㎝ / ℃

Heat Deflection Degree ℃: 50 ~ 75

(D) process

First mortar casting is performed on the first fiber mesh 30a impregnated with the epoxy resin 40 to pour a resin mortar mixture containing a resin mortar and a reinforcing fiber material at a ratio of about 9: 1 to a predetermined thickness. Do the work. The resin mortar is composed of an epoxy resin (22.1% by weight), cement (1.4% by weight), silica (76.4% by weight), and 0.1% by weight of a reinforcing fiber material in a chopped state is mixed therein. As the reinforcing fiber material, any one of fibers selected from glass fibers, carbon fibers, aramids, and kevlar fibers is used.

The epoxy resin 40 has a specific gravity of 1.15 to 1.20, a hardness of M70 to 80, a viscosity of 19,000 to 24,000 CPS, an absorption rate of 0.14% or less, a shrinkage of 1.1% or less, and an equivalent of 180 to 230. The silica is more than 95% purity, specific gravity range is 2.25 ~ 2.65, MOS hardness 6.5 ~ 7.0, PH is 7 ~ 9 is preferred.

(E) process

On the upper side where the primary mortar in the mold 1 is poured, the same second fiber mesh 30b as the first fiber mesh 30a is provided. Thereafter, the mortar mixed in the above step (2) is poured secondly. In addition, after the second mortar is finished, the third fiber mesh 30c, such as the first and second fiber meshes 30a and 30b, is installed in a layered manner. The number of installation of the fiber meshes 30a to 30c may be modified depending on the intended use. However, in the case of the reinforcing plate used for repair reinforcement, three of the fiber meshes 30a to 30c are most preferred. If it is installed above, the strength is increased, but there is a problem that a lot of manufacturing costs, and if it is less than that, there is a problem that the strength is somewhat weakened.

After pouring the first and second mortars, vibration is applied to the entire mold 1 using a general vibrator. When vibration is applied to the mold 1, the first and second fiber meshes 30a and 30b as well as the third fiber mesh 30c may be formed as shown in FIG. The resin is mortar is moved into the state.

After the vibration, the thermal calcining was carried out at 60 ° C. for at least 30 minutes, followed by compression molding at a pressing force of 1000 kg. In addition, after the compression molding is completed it is baked for about 3 hours at about 80 ℃.

(F) process

After completion of the firing by curing for 3 days while maintaining a temperature of 25 ~ 30 ℃ after demolding from the mold 10, it is possible to obtain a fiber-reinforced epoxy resin panel (1) corresponding to one of the above specifications. The mold 10 is to remove the foreign material and then provide to the production of the panel.

<Production Example 1>

A mold 10 having a width (1,000 mm) X length (1,000 mm) X height (11 mm) is prepared. A release agent is applied to the inside of the mold 10. Layer at least three or more fiber meshes 30a-30c over the release agent. On top of each of the laminated fiber meshes 30a to 30c, an epoxy resin (22.1 wt%), cement (1.4 wt%), silica (76.4 wt%) and glass fiber (0.1 wt%) are mixed. Pour. After pouring, the entire mold 10 is vibrated, thermally calcined under infrared light at 60 ° C. for at least 30 minutes, and then compression molded at a pressing force of 1000 kg. After compression molding, the product is calcined at 80 ° C. for 3 hours and then demolded. After demolding, the fiber-reinforced epoxy resin panel (1) having width (1,000 mm) length (1,000 mm) X height (11 mm) was cured by curing for 3 days while maintaining a temperature of 25 to 30 ° C. and a humidity of 40 to 50%. Get The mechanical properties of the fiber-reinforced epoxy resin panel (1) thus obtained were tested, and the results are shown in Table 1 below.

<Mechanical Properties of Fiber Reinforced Epoxy Panel Material> Mechanical properties Test result Remarks Compressive strength (kg / ㎠) 800 Ultimate strain0.017 Direct tensile strength (kg / ㎠) 340 Ultimate strain 0.01 Flexural strength (kg / ㎠) 400 Modulus of elasticity Compression (kg / ㎠) 74,000 Linear limit criteria Tensile (kg / ㎠) 34,000 Ultimate strain Poisson's fee compression 0.34 Seal 0.22 Fracture Strain compression 0.020 0.017 to 0.037 Seal 0.010 0.010 to 0.014 Thermal expansion coefficient 6.5X10 ^-6 Weather resistance Underwater Curing Little impact 3 months Outside exposure Little impact 3 months Chemical resistance Resistant to acids and alkalis

As can be seen from Table 1, the fiber reinforced epoxy panel has a very high compressive strength and tensile strength compared to general concrete, and the flexural strength is relatively large. Therefore, the durability was found to be very excellent.

In addition, winter weathering tests of three months revealed that externally exposed specimens and aquatic specimens were almost unaffected by climatic conditions of temperature and humidity, and underwater lifetime. In addition, the chemical resistance was strongly resistant to acids and alkalis such as hydrochloric acid, sulfuric acid and sodium hydroxide. Therefore, it has been found to be very good for concrete structures that are attacked by seawater, sewage, calcium chloride, and automobile exhaust.

<Production Example 2>

A mold 10 having a width (800 mm) X length (1,500 mm) X height (11 mm) is prepared. A release agent is applied to the inside of the mold 10. Layer at least three or more fiber meshes 30a-30c over the release agent. On top of each of the laminated fiber meshes 30a to 30c, a mixed resin mortar obtained by mixing epoxy resin (23.9 wt%), cement (1.5 wt%), silica (74.5 wt%) and glass fiber (0.1 wt%) Pour. After pouring, the entire mold 10 is vibrated, thermally calcined under infrared light at 60 ° C. for at least 30 minutes, and then compression molded at a pressing force of 1000 kg. After compression molding, the sample is calcined at 80 ° C. for 3 hours and then demolded. After demolding, curing was carried out for 3 days while maintaining the temperature of 25 ~ 30 ℃, to obtain a fiber-reinforced epoxy resin panel (1) having a width (800mm) X length (1,500mm) X height (11mm). The mechanical properties of the fiber-reinforced epoxy resin panel (1) thus obtained were tested, and the results are shown in Table 1 above.

<Production Example 3>

A mold 10 having a width (1,000 mm) X length (500 mm) X height (11 mm) is prepared. A release agent is applied to the inside of the mold 10. Layer at least three or more fiber meshes 30a-30c over the release agent. Between the fiber meshes (30a ~ 30c), the epoxy resin (22.1% by weight), cement (1.4% by weight), silica (76.3% by weight), glass fiber (0.2% by weight) is mixed by pouring a mixed resin mortar . After pouring, the entire mold 10 is vibrated, thermally calcined for 30 minutes at 60 ° C, and then compression molded at a pressing force of 1000 kg. After compression molding, the product is calcined at 80 ° C. for 3 hours and then demolded. After demolding, curing was carried out for 3 days while maintaining the temperature of 25 ~ 30 ℃, to obtain a fiber-reinforced epoxy resin panel (1) having a width (1,000mm) X length (500mm) X height (11mm). The mechanical properties of the fiber-reinforced epoxy resin panel (1) thus obtained were tested, and the results were also shown in Table 1 above.

3 is a cross-sectional view showing a construction state of the epoxy resin panel for fiber reinforcement according to the present invention.

Fiber-reinforced epoxy resin panel (1) manufactured in various standards as described above is used for repair and reinforcement of the concrete structure, if described with reference to the installation process as follows. First, the surface of the concrete structure 80 is treated.

<Pretreatment of Concrete Structure Surface>

① Set repair and reinforcement range of concrete structure 80 and measure it. ② Investigate the compressive strength of concrete structure 80. ③ Prepare the repair and reinforcement interface ④ Remove the deteriorated concrete of the concrete structure 80, treat the surface, and repair the corroded rebar if necessary ⑤ Inject the low viscosity injection material into the cracked area ⑥ Construct and cure surface protection concrete to make the surface flat. ⑦ Clean the rebar and concrete surface.

Secondly, the fiber reinforced epoxy panel 1 is installed on the concrete structure 80 to be repaired and reinforced.

<Installation of Fiber Reinforced Epoxy Panel>

① Ensure sufficient fixing length of epoxy panel (1) for adhesion of fiber-reinforced epoxy panel (1) to the surface of concrete structure (80). ② If required, make the required joint. ③ fixing the fiber reinforced epoxy panel (1) to the surface of the concrete structure (80) uses an anchor bolt or a chemical anchor bolt (84). ④ Since the epoxy adhesive must be injected, the fiber-reinforced epoxy panel 1 is spaced about 4 ± 2 mm with a spacer or the like on the surface of the concrete structure 80 and anchored securely as an anchor bolt or a chemical anchor bolt 84. Do it. Anchor mounting holes are installed in advance using a drill. Since the distance between the surface of the concrete structure 80 and the fiber-reinforced epoxy panel 1 is as close as possible, the distance is kept as close as possible. ⑤ Remove the head of the anchor bolt 84 or use an anchor cap to prevent rust. In addition, anchor bolts should not be installed more than 100mm at the end, considering the tightness of joints, etc., and should be based on 9 pieces per 1㎡. ⑥ The length of the anchor 84 should be at least 2 ~ 3 times the depth to the deteriorated part. In general, the interval should be 30cm.

Next, the adhesive epoxy is injected.

<Epoxy adhesive injection>

① Before injecting the epoxy adhesive 90 at the interval between the concrete structure 80 and the fiber reinforced epoxy panel 1, first seal the interface of the fiber reinforced epoxy resin panel using a sealant having fire resistance and durability. do. ② The epoxy adhesive 90 uses a low viscosity epoxy, the main required properties of the epoxy adhesive 90 is the same as the physical properties of the epoxy resin used in the step (C). ③ It is recommended to check the properties and construction conditions of the epoxy resin for adhesion by mockup test before construction. ④ Epoxy 90 is forcibly injected, the pressure of the injection device should be 0.5 ~ 2.5㎏ / ㎠. The injection method is repeated injections from low pressure to high pressure. Inject epoxy resin very slowly to avoid bubbles. (5) Apply when the air temperature is 5 ~ 30 ℃.

<Cure>

After the injection of the epoxy adhesive 90 is completed, curing for 3 days. In case of outdoor construction, protect it by covering it with vinyl sheet, curing cloth, etc. after drying the surface as necessary to prevent rain water, sand, dust, etc. from being attached. At this time, vinyl sheet or curing cloth should not touch the construction surface. In addition, after finishing the construction, the finish is finished with an epoxy panel that is suitable for the aesthetic condition. In particular, when a beautiful aesthetic is required, it is preferable to remove the head such as the anchor bolt.

Figure 4A is a plan view of a corner casting member made to be suitable for using the fiber reinforced epoxy resin panel according to the present invention as a corner reinforcement plate of the container, Figure 4B is a side view, Figure 4C shows a construction state, respectively .

The epoxy resin panel 100 used as a corner casting member reinforces the bottom 110 on which containers such as a container box loading dock are placed to protect the bottom 110 of the loading dock which may be damaged due to the load of the container box. The epoxy resin panel 100 for the corner casting member is installed at a position corresponding to each corner (four corners) of the container box at the loading dock. Reference numeral 90a denotes an epoxy adhesive used when the resin panel 100 is installed on the bottom 110.

Epoxy resin panel 100 for corner casting members is also manufactured in various standards {(420 X 1350 X 20 (mm), 420 X 600 X 20 (mm), 1000 X 1350 X 20 (mm)), It is manufactured through the same process as described in (A) to (F), except that the epoxy resin panel 100 for the corner casting member is further subjected to at least four or more fiber meshes and thus mortar casting operations to increase the strength. It differs only in the amount of the compound and some of the ingredients.

According to the present invention as described above, by molding a panel by mixing the fiber chop (Chop) and the fiber mesh in the resin mortar, there is an effect that the physical and mechanical strength is increased, weather resistance and chemical resistance is improved, and There is also an effect of having excellent water retention and reinforcement.

Claims (4)

In the method of manufacturing a panel while applying a release agent to the inside of the mold, Layering at least three or more fiber meshes over the release agent; Pouring a mixture of the resin mortar and the reinforcing fiber material mixed in a ratio (9: 1) on each layer of the laminated meshes; Imparting vibration to the entire mold after pouring, and performing compression molding at a pressing force of 1000 kg after thermal firing at 60 ° C. for at least 30 minutes; Calcining at 80 ° C. for 3 hours after compression molding to demold; And Method of producing a fiber-reinforced epoxy resin panel comprising the step of curing for 3 days while maintaining the temperature 25 ~ 30 ℃ after demolding. The method of claim 1, wherein the resin mixture mortar is made of epoxy resin (22.1% by weight), cement (1.4% by weight), silica (76.4% by weight), and reinforcing fibers (0.1% by weight), reinforcing fibers The ash is a fiber reinforced epoxy resin panel, characterized in that any one selected from glass fibers, carbon fibers, aramid and Kevlar fibers. The method of claim 1, further comprising impregnating an epoxy resin in any one of the fiber meshes. In the reinforcement panel molded by the mold, A fiber mesh portion having a release agent applied to the bottom of the mold and laminated at least three or more over the release agent; And It includes a resin mortar portion which is integrated with the fiber meshes by placing the mixture of the resin mortar mixed with the layered fiber meshes and the reinforcing fiber material by the vibration, thermal plasticity, compression molding, demolding, and curing. Fiber reinforced epoxy resin panels.