CN114059720B

CN114059720B - Preparation method of basalt fiber toughened bamboo reinforcement

Info

Publication number: CN114059720B
Application number: CN202111438839.XA
Authority: CN
Inventors: 程宝军; 顾晓薇; 王浩; 殷士奇; 李晓慧; 张伟峰
Original assignee: Northeastern University China
Current assignee: Northeastern University China
Priority date: 2021-11-30
Filing date: 2021-11-30
Publication date: 2023-02-03
Anticipated expiration: 2041-11-30
Also published as: CN114059720A

Abstract

The invention belongs to the field of building materials, and particularly relates to a preparation method of basalt fiber toughened bamboo reinforcement capable of replacing steel bars, bamboo reinforcement and basalt reinforcement; (1) Preparing bamboo strips with the length of 20 to 25mm, the width of 8 to 10mm and the thickness of 8 to 10 mm; (2) Taking basalt fibers with the length of 20 to 25mm and the monofilament diameter of 10 to 13 mu m for later use; (3) according to the mass ratio of the component A to the component B of 1-1.05: 2-2.2 preparing polyurethane adhesive; (4) Bonding the basalt fibers into flaky basalt fiber belts, adhering all the formed flaky basalt fiber belts to the surface layer of the bamboo rib, scraping off redundant polyurethane adhesive, placing on a frame, and curing the adhesive to obtain the basalt fiber toughened bamboo rib. The basalt fiber toughened bamboo reinforcement is light, corrosion resistant, high in tensile strength and strong in toughness.

Description

Preparation method of basalt fiber toughened bamboo reinforcement

Technical Field

The invention belongs to the field of building materials, and particularly relates to a preparation method of basalt fiber toughened bamboo reinforcement capable of replacing steel bars, bamboo reinforcements and basalt reinforcements.

Background

When the reinforcing steel bar is used for preparing reinforced concrete, the reinforcing steel bar has the advantages of good mouldability, reasonable strength-to-price ratio, good fire resistance, good durability, strong capability of adapting to disaster environments, good integrity of an integrally cast reinforced concrete structure, good performance for resisting earthquake, wind load and explosion impact, local material availability and the like. But the problems are also obvious: the self gravity is large, which brings difficulties to large span structures, high-rise building structures and earthquake resistance, and transportation and construction hoisting. In addition, the reinforced concrete structure has poor crack resistance, members such as tension members and bending members are often subjected to crack operation in normal use, and the construction cost needs to be increased to meet the requirements of structures which are not allowed to have cracks or have strict limitation on the width of the cracks. In addition, the reinforced concrete structure has poor heat and sound insulation performance, and the surface of the steel bar has poor acid corrosion resistance. We are therefore asked to move the reinforcement to a more acid resistant and lighter weight.

Bamboo as a cheap and biodegradable 'green' material can grow rapidly, and the use of the bamboo in the field of buildings undoubtedly accords with the concept of environmental protection. Meanwhile, the requirements of light-weight reinforcement are met, but the bamboo reinforcement is thick and strong, has a large number of problems, poor fire resistance and relatively poor durability, and meanwhile, the common bamboo reinforcement has the defects of low tensile strength, small elastic modulus, large difference of linear expansion coefficients in the longitudinal direction and the transverse direction of the bamboo reinforcement, poor bonding performance with concrete and the like in material performance compared with the reinforcement. When general bamboo reinforced concrete members are damaged, the common bamboo reinforced concrete members are often damaged in a brittle way, namely, no obvious sign is generated in the damage, and the common bamboo reinforced concrete members are damaged when cracks appear. At the same time, the bamboo reinforcement is difficult to apply prestress so as to be used in a large span structure. Therefore, the bamboo reinforcement is required to be developed toward high strength and high durability.

The basalt fiber Bar (BFRP) is a novel composite material formed by combining basalt fibers serving as a reinforcing material with synthetic resins (unsaturated polyester, epoxy resin, vinyl resin and the like) and matrixes such as fillers, curing agents and the like through a pultrusion process. Different from the steel bar, the density of the basalt fiber bar is 1.9 to 2.1g/cm ³ About 1/4 of the steel bar (the density of the steel bar is 7.8-7.9); the tensile yield strength of the basalt fiber bar is 2-3 times of that of the steel bar, the thermal expansion coefficient of the basalt fiber bar is similar to that of the concrete, and the synchronous deformation of the concrete and the bar material is ensured. Basalt fiber cord is a non-corrosive electrical insulator with non-magnetic properties, especially: has extremely high acid resistance and alkali resistance. Has high tolerance for the water concentration in cement mortar and the permeation and diffusion of carbon dioxide, and can prevent the corrosion of concrete structures in severe environment, thereby achieving the effect of improving the durability of buildings. The concrete has excellent strength and tensile property, but has overlarge brittleness, is easy to break, and cannot make up the loss of the flexural strength of the concrete in the using process, so that the concrete has a problem in the application range. Therefore, the development of high toughness is urgently needed.

The invention provides a preparation method of a nitrite intercalated hydrotalcite material modified steel bar epoxy resin coating material, which is characterized by comprising the following steps: adding nitrite intercalation hydrotalcite material and silane into a silane organic mixed solution according to a certain mass ratio, carrying out water bath magnetic stirring, carrying out separation treatment, washing with a mixed solution of ethanol and deionized water until the pH value is neutral, and carrying out vacuum drying to obtain a dried substance; grinding the dried substance into fine powder, adding the fine powder into n-butanol organic solvent, and performing ultrasonic dispersion to obtain organic solvent dispersion solution; adding epoxy resin into the organic solvent dispersion solution, and performing ultrasonic dispersion; adding a polyamide curing agent, dispersing uniformly, and then drying in vacuum to obtain the polyamide curing agent; the invention can not only compact the pore structure of the epoxy resin, block the penetration and invasion of chloride ions and prevent the occurrence of the corrosion of the chloride ions of the steel bar, thereby leading the coating material to have multifunctionality and intelligence and greatly improving the corrosion protection capability of the epoxy resin coating to the steel bar.

The invention belongs to the field of reinforced concrete, and discloses chlorine salt corrosion resistant carbon nanotube modified reinforced concrete and a preparation method thereof, wherein the CN201711095363.8 belongs to the field of reinforced concrete. The invention adopts the combination of chemical acting force and physical method to disperse the carbon nano tube in the polyvinyl alcohol solution, after the carbon nano tube/polyvinyl alcohol pre-polymerized liquid which is evenly distributed and well combined is obtained, the pre-polymerized liquid is added into the cement matrix as the composite modifier, thus obtaining the evenly dispersed carbon nano tube-polyvinyl alcohol-cement based composite material. The method fully combines the reinforcing effects of the hydroxyl carbon nanotube and the polyvinyl alcohol into the composite modified cement-based material, has unique advantages in the aspect of mechanical property, can reduce porosity, captures mobile charges by changing internal microscopic dielectric constant, prevents the formation of corrosion batteries, remarkably reduces corrosion current in reinforced concrete, and prolongs the corrosion resistance time of the reinforced concrete.

CN201120387846.7 utility model provides a bamboo-reinforced concrete integrated configuration comprises bamboo timber, concrete, indulges muscle, stirrup and shear force key jointly, indulges muscle, stirrup component steel reinforcement framework, and concrete parcel steel reinforcement framework just is located bamboo timber upper portion, and the concrete passes through shear force key and bamboo timber zonulae occludens into a whole. The utility model discloses a thoroughly changed the unfavorable situation of bamboo structural rigidity control design, the configuration of indulging muscle and stirrup in the upper portion concrete has improved integrated configuration's bearing capacity greatly to restrain upper portion concrete fracture, reduce the crack width, compare with the bamboo structure, its economic benefits is better, can be applied to civil construction structure field.

CN201610248700.1 discloses a method for reinforcing a masonry wall by a bamboo reinforcement cement mortar surface layer, which is adopted, not only is the construction speed fast, the influence range is small, but also the bearing capacity and the deformation of the masonry wall can be ensured to meet the subsequent use requirements. The bamboo is a renewable natural fast-growing material, and the bamboo mat is adopted to reinforce the existing building, so that the consumption of resource and energy can be effectively reduced, and the sustainability of the existing building transformation industry is improved.

The invention discloses a basalt fiber composite rib and a basalt fiber composite inhaul cable, wherein the basalt fiber composite rib is formed by compounding basalt fibers and carbon fibers under the action of pretension through pultrusion, and the volume ratio of the fibers is 4: 1-1: 1; the basalt fiber composite inhaul cable comprises an outer protective layer and a fiber rib material arranged in the outer protective layer, wherein the fiber rib material comprises a central rib and an outer rib, the central rib is composed of basalt fiber ribs or carbon fiber ribs, the outer rib is composed of basalt fiber composite ribs, a viscoelastic filling layer and an inner sleeve are arranged between the central rib and the outer rib, the inner side of the inner sleeve is connected with the viscoelastic filling layer, and the outer side of the inner sleeve is connected with the outer rib. In the composite inhaul cable, the content of carbon fiber accounts for 25-40% of the total fiber content of the inhaul cable. Compared with the prior art, the basalt fiber composite inhaul cable disclosed by the invention is characterized in that carbon fibers are compounded in basalt fibers, so that the short-term and long-term mechanical properties and chemical properties of the inhaul cable are excellent, and the inhaul cable has the outstanding economic characteristic.

CN201911132297.6 the invention discloses a preparation method of a basalt fiber composite bar, which comprises the following steps of firstly, drawing out continuous basalt fibers from a creel, and fully contacting and mixing the basalt fibers with a resin mixture in an infiltration tank; step two, performing pultrusion on basalt fiber filaments; step three, winding the continuous basalt fibers into bundles; step four, coating the surface; step five, heating and curing; step six, winding the winding drum; step seven, stretching and bending tests; and step eight, obtaining qualified products. Compared with the prior art, the invention has the advantages that: the application of the basalt fiber composite rib in the fabricated building mainly researches the use of the basalt fiber composite rib in a concrete slab instead of a steel bar, determines the technical index of the basalt fiber composite steel bar, improves the performance of the basalt fiber composite rib through the improvement of a production process and a resin formula, and forms the basalt fiber composite rib plate which can be used in the fabricated building and can form a brand new industry.

The comprehensive analysis of the novel rib material and the traditional rib material of the invention mainly has the following problems. The main problem of the steel bars is that the steel bars are too heavy in volume weight and cannot be better suitable for modern high-rise buildings, and a new steel bar needs to be innovated urgently to meet the requirements of light weight and high strength of modern buildings; the basalt bars have the main problems that the brittleness is too large, the toughness of the concrete cannot be well increased and the shear resistance and tensile strength of the concrete cannot be improved by combining the concrete which is also a brittle material, and the basalt bars do not have good synergistic effect with the concrete and cannot be suitable for a concrete structure; the main problem of bamboo muscle, because the bamboo muscle material is unstable, consequently the bamboo muscle performance is unstable, is difficult to batch production, and the tensile strength of bamboo muscle is far less than reinforcing bar and basalt muscle simultaneously, so cause it can't be used for the building main part, play effectual effect.

Disclosure of Invention

The invention aims to overcome the defects of the prior art and provides the preparation method of the basalt fiber toughened bamboo rib, which is light, corrosion-resistant, high in tensile strength and strong in toughness.

In order to solve the technical problem, the invention is realized as follows:

the preparation method of the basalt fiber toughened bamboo reinforcement is implemented according to the following steps in sequence:

(1) Preparing bamboo strips with the length of 20-25 mm, the width of 8-10 mm and the thickness of 8-10 mm;

(2) Taking basalt fibers with the length of 20-25 mm and the monofilament diameter of 10-13 mu m for later use;

(3) According to the mass ratio of the component A to the component B of 1-1.05: 2-2.2 preparing polyurethane adhesive;

(4) And (3) bonding the basalt fibers obtained in the step (2) into flaky basalt fiber belts by adopting the polyurethane adhesive in the step (3), adhering all the formed flaky basalt fiber belts to the surface layer of the bamboo rib, scraping off the excessive polyurethane adhesive, placing on a frame, and curing the adhesive to obtain the basalt fiber toughened bamboo rib.

Furthermore, the width of the bamboo strip in the step (1) is 10mm, the thickness of the bamboo strip is 10mm, and the tensile strength is more than or equal to 100MPa.

Furthermore, the monofilament in the step (2) of the invention has a diameter of 13 μm and a tensile strength of not less than 10MPa.

Further, the component A of the polyurethane adhesive in the step (3) of the invention comprises 70-90 parts of trifunctional polyether polyol with the molecular weight of 300-500, 5-12 parts of cross-linking agent, 5-25 parts of DOP or DBP plasticizer and 0.1-0.3 part of metal catalyst; the component B is polyphenyl polymethylene polyisocyanate 100-220.

Furthermore, the cross-linking agent is one or a mixture of more than two of glycerol, trimethylolpropane and pentaerythritol.

Furthermore, the metal catalyst is one or a mixture of more than two of lead isooctanoate, bismuth isooctanoate and potassium isooctanoate.

Further, in the step (4) of the invention, all the formed flaky basalt fiber tapes are longitudinally stuck to the surface layer of the bamboo rib.

Further, in the step (4) of the invention, the basalt fiber single layer obtained in the step (2) is bonded into the flaky basalt fiber belt.

The novel reinforcement material, namely the basalt bamboo reinforcement material, has the characteristics of rich functions, low volume weight, high tensile strength, high toughness, wide application scene, strong durability, low cost, high environmental protection effect and the like, and is prepared by selecting bamboo wood and basalt fiber and adding an adhesive. The novel reinforcement solves the problems that the reinforcement is too heavy, the basalt reinforcement is too brittle, and the tensile strength of the bamboo reinforcement is too low. Meanwhile, due to the combination of the bamboo ribs and the basalt fibers, the performance of the bamboo is stabilized, the mass production of the basalt bamboo ribs becomes possible, and the quality is stabilized. Simultaneously, the advantages of the two materials are exerted, the high toughness and the low volume weight of the bamboo materials are well combined with the high tensile strength and the durability of the basalt fiber, and the advantages are complemented.

Compared with the products on the market, the product not only achieves light weight, high toughness and high strength in performance, the tensile strength can reach 500MPa, and the volume weight is only 1000kg/m ³ The material is suitable for more building fields, has wider application range, greatly widens the application scenes, and solves the problem that high-rise buildings need light, high-toughness and high-strength materials; meanwhile, the production cost is saved, the bamboo wood is a renewable resource, the bamboo wood resource is rich in southern areas, and when people go to mining and comprehensive utilization, the basalt fiber is basalt hot-melt drawn wire, the existing mature technology and process in China use a small amount of adhesive, and the cost is far lower than that of the traditional reinforcing steel bars such as reinforcing steel bars; finally, in the aspect of environmental protection, renewable resources are used, pollution-free fibers are used, and the carbon emission of the whole life cycle of the building can be greatly reduced when the fiber is used for building.

Compared with the prior art, the invention has the following characteristics:

firstly, the basalt fiber toughening bamboo rib improves the toughness compared with the basalt fiber; compared with the bamboo ribs, the tensile strength of the bamboo ribs is improved; compared with the reinforcing steel bar, the weight of the reinforcing steel bar is reduced, and the durability of the reinforcing steel bar is improved. The basalt fiber is longitudinally bonded on the surface layer of the bamboo rib, and the performance of the basalt modified bamboo rib can be comprehensively improved by utilizing the high tensile strength of basalt and the flexural strength of bamboo. Meanwhile, bamboo and basalt fibers are adopted, renewable resources and 'stone wire drawing' are utilized, and the method is green, energy-saving and environment-friendly and accords with the concept and strategy of sustainable development.

TABLE 1 comparison of the Properties of bars of different materials

Compared with the reinforcing steel bar, the bulk density is 7850kg/m ³ The basalt fiber toughened bamboo rib has the volume weight of1300kg/m ³ The volume weight of the ribs is greatly reduced, and the basalt fiber toughened bamboo ribs can be used for high-rise buildings, so that the gain effect is obvious; compared with the basalt bar, the basalt bamboo bar greatly improves the toughness, can toughen 30-50%, enables the basalt bar to get rid of brittleness, becomes a novel green concrete structure bar, can expand the application range and functions of the novel green concrete structure bar, and widens the way for the development of products; compared with bamboo ribs, the basalt fiber toughened bamboo rib outer layer is coated with basalt fibers, is acid and alkali resistant, greatly improves the durability of the bamboo rib, greatly improves the tensile strength of the basalt fibers and the adhesive, and can be used for non-mechanism construction and structural concrete simultaneously compared with the bamboo ribs. The basalt fiber toughened bamboo rib has the characteristics of lighter weight, corrosion resistance, high toughness and high strength, and is more suitable for concrete structures.

Drawings

FIG. 1 is a schematic view of basalt toughened bamboo reinforcement manufactured in example 1 of the present invention;

fig. 2 is a schematic view of basalt toughened bamboo reinforcement manufactured in embodiment 2 of the present invention.

Detailed Description

The basalt fiber reinforced bamboo reinforcement according to the present invention will be described in further detail with reference to the following examples, but the present invention is not limited to the following examples.

Example 1

(1) Preparing bamboo strips with the length of 20-25 mm, the width of 10mm and the thickness of 10 mm;

(2) Taking basalt fibers with the length of 20-25 mm and the monofilament diameter of 13 mu m for later use;

(3) The component A of the polyurethane adhesive comprises 70 parts of trifunctional polyether polyol with the molecular weight of 300, 5 parts of cross-linking agent glycerol, 7 parts of trimethylolpropane, 17.8 parts of DOP plasticizer and 0.2 part of metal catalyst lead isooctanoate; the component B is 150 parts of polyphenyl polymethylene polyisocyanate;

(4) Adopting the polyurethane adhesive in the step (3) to bond the basalt fiber obtained in the step (2) into a sheet-shaped basalt fiber belt in a single layer manner, so that repeated bonding is avoided, and the tensile property of the basalt fiber is prevented from being influenced; and longitudinally sticking all the formed flaky basalt fiber tapes to the surface layer of the bamboo rib, scraping off the excessive polyurethane adhesive, putting the bamboo rib on a frame, and curing the adhesive to obtain the basalt fiber toughened bamboo rib.

Example 2

(2) Taking 20-25 mm basalt fiber with monofilament diameter of 13 mu m;

(3) The component A of the polyurethane adhesive comprises 70 parts of trifunctional polyether polyol with the molecular weight of 300, 5 parts of cross-linking agent glycerol, 7 parts of trimethylolpropane, 17.8 parts of DBP plasticizer and 0.2 part of metal catalyst lead isooctanoate; the component B is 200 parts of polyphenyl polymethylene polyisocyanate;

(4) Adopting the polyurethane adhesive in the step (3) to bond the basalt fiber single layer obtained in the step (2) into a sheet-shaped basalt fiber belt without repeated bonding, so as to avoid influencing the tensile property of the basalt fiber; and longitudinally sticking all the formed flaky basalt fiber belts to the surface layer of the bamboo rib, scraping off the redundant polyurethane adhesive, putting on a frame, and curing the adhesive to obtain the basalt fiber toughened bamboo rib.

TABLE 2 comparison of the Properties of basalt bamboo Reinforcement with different proportions of the adhesive component

The foregoing is merely exemplary and illustrative of the present invention and it is within the purview of one skilled in the art to modify or supplement the embodiments described or to substitute similar ones without the exercise of inventive faculty, and still fall within the scope of the claims.

Claims

1. The preparation method of the basalt fiber toughened bamboo reinforcement is characterized by comprising the following steps of:

(1) Preparing bamboo strips with the length of 20-25 cm, the width of 10mm and the thickness of 10 mm;

(2) Taking basalt fibers with the length of 20-25 cm and the monofilament diameter of 13 mu m for later use;

(3) According to the mass ratio of the component A to the component B of 1-1.05: 1-2.2 preparing polyurethane adhesive;

(4) Adopting the polyurethane adhesive in the step (3) to bond the basalt fiber single layer obtained in the step (2) into a sheet-shaped basalt fiber belt without repeated bonding; and longitudinally sticking all the formed flaky basalt fiber belts to the surface layer of the bamboo batten, scraping off the redundant polyurethane adhesive, putting on a frame, and curing the adhesive to obtain the basalt fiber toughened bamboo rib.

2. The preparation method of the basalt fiber toughened bamboo reinforcement according to claim 1, which is characterized by comprising the following steps: the component A of the polyurethane adhesive in the step (3) comprises 70 to 90 parts of trifunctional polyether polyol with the molecular weight of 300-500, 5 to 12 parts of cross-linking agent, 5 to 25 parts of DOP or DBP plasticizer and 0.1 to 0.3 part of metal catalyst; the component B is 100 to 220 parts of polyphenyl polymethylene polyisocyanate.

3. The preparation method of the basalt fiber toughened bamboo reinforcement according to claim 2, wherein: the cross-linking agent is one or more of glycerol, trimethylolpropane and pentaerythritol.

4. The preparation method of the basalt fiber toughened bamboo reinforcement according to claim 2, wherein: the metal catalyst is one or more of lead isooctanoate, bismuth isooctanoate and potassium isooctanoate.