Preparation device and method of hybrid fiber cloth for reinforcing concrete structure

Abstract

The invention relates to the technical field of preparation of fiber cloth, in particular to a preparation device and method of hybrid fiber cloth for reinforcing a concrete structure, and the hybrid fiber cloth is prepared from the following components in percentage by volume: 9% of 55% basalt fiber, 10% of 40% carbon fiber and 5% of epoxy resin. The basalt fiber can be naturally degraded, has good thermal insulation performance, sound insulation performance, corrosion resistance, non-toxicity, durability and mechanical performance and is slightly low in elasticity modulus, the carbon fiber is moderate in price, high in elasticity modulus and low in ductility, fiber cloth with different strengths, elasticity moduli and ductility is used in a mixed mode, the advantages of various fibers are brought into play, and the composite material has the advantages of being good in heat insulation performance, sound insulation performance, corrosion resistance, non-toxicity, durability and mechanical performance. And the effects of complementing advantages and avoiding disadvantages are achieved.

Description

Technical Field

[0001] The invention relates to the technical field of fiber cloth preparation, and in particular to a preparation device and method of mixed fiber cloth for reinforcing concrete structure. Background Art

[0002] Hybrid composite fiber materials are composed of two or more composite materials. They are usually made by reinforcing the same matrix with two or more fibers. Through reasonable design, fiber materials with excellent comprehensive performance are obtained. Hybrid composite materials were studied and developed in the early 1970s. They can not only reduce costs, but also complement each other and produce hybrid effects. They have been widely used in aviation, aerospace, automobile and shipbuilding industries. Basalt fiber is a new type of environmentally friendly inorganic composite material that can be naturally degraded and independently developed by my country. In addition to a slightly lower elastic modulus, it has good thermal insulation, sound insulation, corrosion resistance, non-toxicity, durability and mechanical properties, good ductility and relatively cheap price; carbon fiber has high tensile strength and elastic modulus, but its elongation is low and the market price is high.

[0003] At present, some civil engineering structures are reinforced by unidirectional hybrid fiber materials, but the properties of unidirectional hybrid fiber materials are different, and the degree of reinforcement after combining with civil engineering buildings is also different. Under the premise of ensuring the proper bearing capacity, it is necessary to enhance the ductility of civil engineering structure reinforcement components, reduce reinforcement costs, and improve the capacity and applicability of fiber materials. Summary of the invention

[0004] In order to obtain a hybrid composite fiber material with excellent ductility, high strength and low price, which is suitable for strengthening civil engineering structures, the present invention provides a preparation device and method of a hybrid fiber cloth for strengthening concrete structures.

[0005] The present invention provides a device and method for preparing a hybrid fiber cloth for reinforcing a concrete structure, which adopts the following technical scheme: A method for preparing a hybrid fiber cloth for reinforcing a concrete structure comprises the following components by volume fraction: 55% basalt fiber 9, 40% carbon fiber 10, and 5% epoxy resin.

[0006] By adopting the above technical scheme, different types of fiber hybrid composite materials are mixed between layers to obtain unidirectional hybrid fiber materials suitable for reinforcement of civil engineering structures. The tensile strength, elastic modulus and ductility are compared with unidirectional single-type fiber materials to obtain hybrid composite fiber materials with moderate ratio, excellent ductility, high strength and low price.

[0007] A preparation device for mixed fiber cloth for reinforcing concrete structure comprises a yarn rack, a dipping tank, a yarn threading plate, a weaving workshop, a graded heating channel, a roller, a cutting and processing milling machine, and a traction machine. A plurality of bundles of basalt fibers and a plurality of bundles of carbon fibers are woven into a single-layer mixed fiber cloth through the weaving workshop.

[0008] By adopting the above technical scheme, basalt fiber is a new type of environmentally friendly inorganic composite material that can be naturally degraded. Except for its slightly low elastic modulus, it has good thermal insulation, sound insulation, corrosion resistance, non-toxicity, durability and mechanical properties, good ductility and relatively low price; carbon fiber has high tensile strength and elastic modulus, but its elongation is low and its market price is high; under the premise of ensuring the due bearing capacity, the ductility of the reinforced components is enhanced and the reinforcement cost is reduced, and the fiber bundles of basalt fiber and carbon fiber are woven perpendicular to each other to form a single-layer mixed fiber cloth.

[0009] A preparation method of a hybrid fiber cloth for reinforcing a concrete structure comprises the following steps: step A, feeding a basalt fiber roving fiber bundle and a carbon fiber roving fiber bundle into a dipping tank through a traction machine for dipping; step B, operating a textile tool to weave a single-layer hybrid fiber cloth; step C, applying epoxy resin to the single-layer hybrid fiber cloth, and weaving multiple layers of hybrid fiber cloth; step D, heating and curing the multiple layers of hybrid fiber cloth in stages; and step E, extruding the multiple layers of hybrid fiber cloth and cutting the length of the multiple layers of hybrid fiber cloth through a milling machine.

[0010] By adopting the above technical scheme, basalt fiber and carbon fiber are woven into cloth respectively, that is, fiber cloths with different strengths, elastic moduli and elongations are mixed and used to give full play to the advantages of various fibers, realize complementary advantages, and avoid weaknesses, so as to facilitate the acquisition of mixed composite fiber materials with excellent ductility, high strength and low price.

[0011] Preferably, in step A, the specific operation steps of sending the fiber bundles into the dipping tank through the traction machine for dipping include: two initiators are placed in the dipping tank, the two initiators include tert-butyl perbenzoate and benzoyl peroxide, and the basalt fiber roving fiber bundles and the carbon fiber roving fiber bundles undergo low-temperature cross-linking reactions and high-temperature cross-linking reactions with the corresponding initiators, respectively.

[0012] By adopting the above technical solution, the low-temperature curing temperature is the low-temperature cross-linking reaction temperature, and the high-temperature curing temperature is the high-temperature cross-linking reaction temperature. Through the initiator, the mixed fiber cloth is conveniently cured and formed.

[0013] Preferably, in step C, the single-layer mixed fiber cloth is coated with epoxy resin, and the specific operation steps of weaving multiple layers of mixed fiber cloth include: C1, laying the single-layer mixed fiber cloth on the operating table, evenly brushing the epoxy resin and scraping it flat, and placing a layer of absorbent gauze; C2, evenly brushing the epoxy resin again and scraping it flat, and then placing another layer of mixed fiber cloth, and repeating the above operation until N (N≤5) layers of mixed fiber cloth are obtained.

[0014] By adopting the above technical solution, the absorbent gauze has a certain water absorption capacity, which is beneficial to reduce the moisture loss of the building wall when reinforcing the building. The epoxy resin in the multi-layer mixed fiber cloth is uniform, which is convenient for subsequent extrusion molding.

[0015] Preferably, in step C, the specific operation steps of weaving the multi-layer hybrid fiber cloth include: C3, applying a layer of polyamide curing agent to the N layers of the hybrid fiber cloth.

[0016] By adopting the above technical solution, the polyamide curing agent is conducive to the rapid curing of the epoxy resin between the layers, while increasing the toughness of the epoxy resin, making it easier to extrude the epoxy resin in later processing.

[0017] Preferably, in step D, the specific operation steps of the graded heating and curing of the multi-layer hybrid fiber cloth include: D1, low-temperature heating of N layers of the hybrid fiber cloth, wherein the low temperature includes 80°C~150°C; the specific operation steps of the graded heating and curing of the multi-layer hybrid fiber cloth include: D2, high-temperature heating of the N layers of the hybrid fiber cloth until cured, wherein the high temperature includes 190°C~205°C.

[0018] By adopting the above technical solution, the thermosetting resin becomes soft and plastic through low-temperature preheating, and is cured at high temperature to prevent the thermosetting resin in the mixed fiber cloth from flowing downward due to the change in the center of gravity, while facilitating the improvement of the uniformity of the mixed fiber cloth.

[0019] In summary, the present invention has the following beneficial technical effects: 1. The hybrid fiber cloth of the present invention is a hybrid interweaving of basalt fiber and carbon fiber. Basalt fiber can be naturally degraded, has good thermal insulation, sound insulation, corrosion resistance, non-toxicity, durability and mechanical properties, and has a slightly low elastic modulus. Carbon fiber has a moderate price, a high elastic modulus and a low elongation. Fiber cloths with different strengths, elastic moduli and elongations are mixed and used to give full play to the advantages of various fibers, achieve complementary advantages, and play to their strengths and avoid their weaknesses. By weaving the hybrid fiber cloth, a hybrid composite fiber material with excellent ductility, high strength and low price can be obtained; 2. The thermosetting resin matrix and fiber bundles in the multi-layer hybrid fiber cloth of the present invention are evenly distributed in the cut and formed multi-layer hybrid fiber cloth. The tensile strength, elastic modulus and ductility of the multi-layer hybrid fiber cloth are enhanced by the even fiber bundles, thereby improving the capacity and applicability of the fiber material. Compared with unidirectional single-type fiber materials, the unidirectional hybrid fiber material is more suitable for the reinforcement of civil engineering structures, and the cost required for reinforcement is reduced; 3. The present invention has two graded heating processes, low-temperature preheating and high-temperature curing. The hybrid fiber cloth is preheated first. The originally liquid thermosetting resin matrix in the hybrid fiber cloth transitions from a liquid state to a gel state during the low-temperature curing process, gradually loses fluidity and becomes soft and plastic. At the same time, the temperature of the hybrid fiber cloth is also increased to a certain extent. The hybrid fiber cloth quickly reaches the high-temperature curing temperature and is completely cured under the action of high temperature, which effectively alleviates the problem of the downward flow of the thermosetting resin matrix due to gravity. The fully cured hybrid fiber cloth has good uniformity, greatly improves product performance and product quality, and reduces the accumulation of waste glue in the heating channel during high-temperature curing. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is a working diagram of each device in a device for preparing a hybrid fiber cloth for reinforcing a concrete structure according to the present invention; Figure 2 It is a schematic diagram of the structure of the multi-layer mixed fiber cloth in the present invention; Figure 3 It is a flow chart of a method for preparing a hybrid fiber cloth for reinforcing a concrete structure in the present invention; Figure 4 It is a data table of different reinforcing fiber density, tensile strength and elastic modulus of the hybrid fiber cloth in the present invention.

[0021] Description of reference numerals: 1. Yarn rack; 2. Glue dipping tank; 3. Yarn threading plate; 4. Textile workshop; 5. Grading heating channel; 6. Roller; 7. Cutting and milling machine; 8. Traction machine; 9. Basalt fiber; 10. Carbon fiber. DETAILED DESCRIPTION

[0022] The following is combined with Figure 1-Figure 3 The present invention is described in further detail.

[0023] The embodiment of the invention discloses a hybrid fiber cloth for reinforcing a concrete structure.

[0024] Fibers with different strengths, elastic moduli, and elongations are mixed and used to give full play to the advantages of various fibers, achieve complementary advantages, and overcome weaknesses. Basalt fiber 9 (basalt fiber 9 is represented by B in the table) and carbon fiber 10 (carbon fiber 10 is represented by C in the table) are composed of the following components by volume fraction: 55% basalt fiber 9, 40% carbon fiber 10, and 5% epoxy resin. Basalt fiber 9 (B) can be naturally degraded and has good thermal insulation, sound insulation, corrosion resistance, non-toxicity, durability and mechanical properties, and has a slightly lower elastic modulus. Carbon fiber 10 (C) is moderately priced, has a higher elastic modulus and a lower elongation. Basalt fiber 9 (B) and carbon fiber 10 (C) are mixed and woven into a mixed fiber cloth to obtain a mixed composite fiber material with excellent ductility, high strength and low price.

[0025] The embodiment of the present invention also discloses a device for preparing a mixed fiber cloth for reinforcing a concrete structure.

[0026] Reference Figure 1 , including a yarn rack 1, a dipping tank 2, a yarn threading plate 3, a weaving workshop 4, a graded heating channel 5, a roller 6, a cutting and processing milling machine 7, and a traction machine 8. A plurality of bundles of basalt fibers 9 and a plurality of bundles of carbon fibers 10 are woven into a single-layer mixed fiber cloth through the weaving workshop 4. A plurality of single-layer mixed fiber cloths of not less than five layers are woven into a multi-layer mixed fiber cloth in the weaving workshop 4. After the multi-layer mixed fiber cloth comes out of the weaving workshop 4, a curing agent is added, and the multi-layer mixed fiber cloth is put into the graded heating channel 5 for shaping, and then extruded and formed by the roller 6, so that the roller 6 rolls the multi-layer mixed fiber cloth, so that the thermosetting resin matrix and the fiber bundles in the multi-layer mixed fiber cloth are redistributed evenly, and the tensile strength, elastic modulus and ductility of the multi-layer mixed fiber cloth are enhanced by relying on the uniform fiber bundles, thereby improving the ability and applicability of the fiber material. Compared with unidirectional single-type fiber materials, the unidirectional mixed fiber material is more suitable for the reinforcement of civil engineering structures, and the cost required for reinforcement is reduced.

[0027] The embodiment of the present invention also discloses a method for preparing a hybrid fiber cloth for reinforcing a concrete structure.

[0028] Reference Figure 1 , Figure 2 , Figure 3, including the following operation steps: step A, basalt fiber 9 roving fiber bundles and carbon fiber 10 roving fiber bundles are fed into the dipping tank 2 through the traction machine 8, and under the pulling force of the traction machine 8, the basalt fiber 9 roving and the carbon fiber 10 roving are drawn out from the yarn shaft of the creel 1 of the creel for dipping, and the fiber bundles after dipping need to be dried; step B, the fiber bundles after dipping are separated and dried through the yarn feeding plate 3, and delivered to the textile tools in the textile workshop 4, and the fiber bundles of different reinforcing fibers are woven into a single layer of mixed fiber cloth, operating a textile tool to weave a single layer of mixed fiber cloth; step C, applying epoxy resin to the single layer of mixed fiber cloth, weaving multiple layers of mixed fiber cloth; step D, graded heating and curing the multiple layers of mixed fiber cloth, graded heating the multiple layers of mixed fiber cloth formed in step C; step E, extrusion molding the multiple layers of mixed fiber cloth, cutting and processing the length by a milling machine 7, and extruding and pressing the heated and cured mixed fiber cloth in a roller 6, so that the thermosetting resin matrix and the basalt fibers 9 and the carbon fibers 10 are redistributed evenly.

[0029] Reference Figure 1 , Figure 3 In step A, the traction machine 8 is used to feed the fiber into the dipping tank 2, and the specific operation steps for dipping the fiber include: two initiators are placed in the dipping tank 2, and the two initiators include tert-butyl perbenzoate and benzoyl peroxide. The basalt fiber 9 roving fiber bundle and the carbon fiber 10 roving fiber bundle respectively undergo low-temperature cross-linking reaction and high-temperature cross-linking reaction with the corresponding initiators, and the basalt fiber 9 roving and the carbon fiber 10 roving are uniformly impregnated in a liquid epoxy vinyl ester resin uniformly mixed with low-temperature cross-linking reaction initiator tert-butyl perbenzoate and high-temperature cross-linking reaction initiator benzoyl peroxide, so that the outer surfaces of the basalt fiber 9 roving and the carbon fiber 10 roving are covered with the initiators.

[0030] Reference Figure 1 , Figure 3 In step C, epoxy resin is applied to a single layer of hybrid fiber cloth, and the epoxy resin adopts thermosetting resin. The specific operation steps of weaving multiple layers of hybrid fiber cloth include: C1, laying a single layer of hybrid fiber cloth flat on the operating table, brushing epoxy resin evenly and scraping it flat, placing a layer of absorbent gauze, draining epoxy resin through absorbent gauze, enhancing the adhesion of epoxy resin between layers, and avoiding the situation that the epoxy resin is too thick due to poor control of epoxy resin, so as to facilitate the rapid brushing of epoxy resin; C2, in order to prevent the interlayer cracking of the single layer of hybrid fiber cloth in the later stage, the epoxy resin is brushed evenly again and scraped flat, and then another layer of hybrid fiber cloth is placed, and the above operation is repeated until N (N≤5) layers of hybrid fiber cloth are obtained.

[0031] Reference Figure 1 , Figure 3In step C, the specific operation steps of weaving the multi-layer mixed fiber cloth include: C3, applying a layer of polyamide curing agent to the N-layer mixed fiber cloth. The polyamide curing agent is a curing agent and toughening agent for epoxy resin, which strengthens the connection between the single-layer mixed fiber cloth and can also be used as a preservative to extend the service life of the multi-layer mixed fiber cloth.

[0032] Reference Figure 1 , Figure 3 In step D, the specific operation steps of graded heating and curing the multi-layer hybrid fiber cloth include: D1, low-temperature heating of N layers of hybrid fiber cloth, the low-temperature curing temperature is the low-temperature cross-linking reaction temperature, and the low temperature includes 80°C~150°C, that is, pre-heating the multi-layer hybrid fiber cloth formed in step C, and the multi-layer hybrid fiber cloth enters the graded heating channel 5 to reach the low-temperature curing temperature and starts low-temperature curing, so that the thermosetting resin matrix in the multi-layer hybrid fiber cloth begins to transition from a liquid state to a gel state, reducing the fluidity of the thermosetting resin matrix and increasing the temperature of the multi-layer hybrid fiber cloth, which is convenient for increasing the temperature later to enter high-temperature heating.

[0033] In step D, the specific operation steps of graded heating and curing the multi-layer hybrid fiber cloth include: D2, heating the N layers of hybrid fiber cloth at high temperature until curing, the high temperature includes 190°C~205°C, and the high temperature curing temperature is the high temperature cross-linking reaction temperature.

[0034] The hybrid fiber cloth is preheated first, and then the hybrid fiber cloth reaches the low-temperature curing temperature and begins to perform a relatively gentle low-temperature curing. During this process, the originally liquid thermosetting resin matrix in the hybrid fiber cloth transitions from a liquid state to a gel state during the low-temperature curing process, gradually loses fluidity and becomes soft and plastic. At the same time, the temperature of the hybrid fiber cloth is also increased to a certain extent. In this way, during the high-temperature curing process, the hybrid fiber cloth itself has a certain temperature. Under the action of high temperature, the hybrid fiber cloth quickly reaches the high-temperature curing temperature and is completely cured, which effectively alleviates the downward flow problem of the thermosetting resin matrix caused by gravity. The fully cured hybrid fiber cloth has a good uniformity, and the product performance and product quality are greatly improved. At the same time, the accumulation of waste glue in the heating channel during high-temperature curing is reduced.

[0035] The above are all preferred embodiments of the present invention, and are not intended to limit the protection scope of the present invention. Therefore, any equivalent changes made based on the structure, shape, and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A hybrid fiber cloth for reinforcing concrete structure, characterized in that: The composite material is composed of the following components by volume: 55% basalt fiber (9), 40% carbon fiber (10), and 5% epoxy resin.

2. A device for preparing a hybrid fiber cloth for reinforcing a concrete structure, characterized in that: A mixed fiber cloth for reinforcing a concrete structure as claimed in claim 2 is prepared, comprising a yarn rack (1), a dipping tank (2), a yarn threading plate (3), a weaving workshop (4), a graded heating channel (5), a roller (6), a cutting and processing milling machine (7), and a traction machine (8), wherein a plurality of bundles of basalt fibers (9) and a plurality of bundles of carbon fibers (10) are woven into a single layer of mixed fiber cloth through the weaving workshop (4).

3. A method for preparing a hybrid fiber cloth for reinforcing a concrete structure, characterized in that: The hybrid fiber cloth is prepared by using the device for preparing the hybrid fiber cloth for reinforcing concrete structure according to claim 2, comprising the following steps: Step A, the basalt fiber (9) roving fiber bundle and the carbon fiber (10) roving fiber bundle are sent into the resin dipping tank (2) through the traction machine (8) for resin dipping; Step B, operating a textile tool to weave a single-layer mixed fiber cloth; Step C, applying epoxy resin to a single layer of mixed fiber cloth, and weaving multiple layers of mixed fiber cloth; Step D, stepwise heating and curing of the multi-layered mixed fiber cloth; Step E, the multi-layer mixed fiber cloth is extruded and formed, and the length is processed by a cutting and processing milling machine (7).

4. The method for preparing a hybrid fiber cloth for reinforcing a concrete structure according to claim 3, characterized in that: In step A, the specific operation steps of feeding the material into the dipping tank (2) through the traction machine (8) and dipping the material include: Two initiators are placed in the dipping tank (2), the two initiators comprising tert-butyl perbenzoate and benzoyl peroxide, and the basalt fiber (9) roving fiber bundle and the carbon fiber (10) roving fiber bundle undergo low-temperature crosslinking reaction and high-temperature crosslinking reaction with the corresponding initiators, respectively.

5. The method for preparing a hybrid fiber cloth for reinforcing a concrete structure according to claim 4, characterized in that: In step C, the single-layer mixed fiber cloth is coated with epoxy resin, and the specific operation steps of weaving multiple layers of mixed fiber cloth include: C1, lay a single layer of mixed fiber cloth flat on the operating table, brush epoxy resin evenly and scrape it flat, then put a layer of absorbent gauze; C2, brush the epoxy resin evenly again and scrape it flat, then put another layer of mixed fiber cloth, and repeat the above operation until N (N≤5) layers of mixed fiber cloth are obtained.

6. The method for preparing a hybrid fiber cloth for reinforcing a concrete structure according to claim 5, characterized in that: In step C, the specific operation steps of weaving the multi-layer mixed fiber cloth include: C3, the N-layer mixed fiber cloth is coated with a layer of polyamide curing agent.

7. The method for preparing a hybrid fiber cloth for reinforcing a concrete structure according to claim 6, characterized in that: In step D, the specific operation steps of the stepwise heating and curing of the multi-layer hybrid fiber cloth include: D1, heating the N layers of the mixed fiber cloth at a low temperature, wherein the low temperature includes 80° C. to 150° C.

8. The method for preparing a hybrid fiber cloth for reinforcing a concrete structure according to claim 7, characterized in that: In step D, the specific operation steps of the stepwise heating and curing of the multi-layer hybrid fiber cloth include: D2, heating the N layers of the mixed fiber cloth at a high temperature until solidified, wherein the high temperature includes 190° C. to 205° C.

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