Basalt fiber epoxy mortar and preparation method and application thereof

Abstract

The application provides a basalt fiber epoxy mortar and a preparation method and application thereof, and belongs to the technical field of building materials.The basalt fiber epoxy mortar provided by the application does not contain cement and mineral powder, the recycled basalt fiber powder treated by a silane coupling agent on the surface completely replaces the cement and mineral powder in the traditional epoxy mortar, the quartz sand and quartz powder are used to provide a skeleton, and modified nano-SiO2 is used to improve the compactness of the mixture, so that the synergistic optimization of high toughness, high strength and low carbon emission is realized.The 7-day compressive strength of the epoxy fiber mortar obtained by the application is greater than or equal to 110MPa, the bending strength is greater than or equal to 70MPa, the drying shrinkage rate is less than or equal to 0.5%, the interfacial pull-out strength with concrete is greater than or equal to 5.5MPa, the carbon emission is reduced by about 40% compared with the traditional epoxy mortar, and the high-value utilization of building solid waste and the green application of high performance are realized.

Description

Technical Field

[0001] This invention belongs to the field of building materials technology, specifically relating to a basalt fiber epoxy mortar, its preparation method, and its application. Background Technology

[0002] Epoxy mortar, a high-performance material composed of organic polymer resin (epoxy resin) and inorganic fillers and aggregates, is widely used in building structure reinforcement and repair, bridge and road paving, wear-resistant flooring of industrial plants, erosion and abrasion protection of water conservancy and hydropower projects, and foundation anchoring of precision equipment, thanks to its excellent bonding strength, mechanical properties, chemical stability and rapid curing characteristics.

[0003] Traditional epoxy mortar systems typically use epoxy resin and a curing agent as the organic binder, silicate cement and active mineral admixtures (such as mineral powder and fly ash) as the inorganic cementitious reinforcing phase, and then add quartz sand / powder of different gradations as aggregate. While this system combines the toughness of organic materials with the rigidity of inorganic materials to some extent, it still has the following inherent defects and challenges: 1. High carbon footprint and environmentally unfriendly: The production of cement and mineral powder is a typical high-energy-consuming and high-carbon-emission process. The extensive use of these materials in traditional epoxy mortars results in persistently high carbon emissions throughout their entire life cycle.

[0004] 2. Insufficient toughness and risk of brittle failure: Cement stone itself is a brittle material. When subjected to impact, fatigue load or temperature stress, traditional epoxy mortar is prone to brittle failure due to the weak interface between the inorganic and organic phases or the cracking of the cement stone itself, which limits its long-term reliability under dynamic loads or harsh environments.

[0005] 3. Significant drying shrinkage: The cement hydration process is accompanied by chemical shrinkage and drying shrinkage. Although epoxy resin can partially inhibit this shrinkage, the overall shrinkage rate of traditional systems is still relatively high (usually >0.8%). Excessive shrinkage can lead to internal stress accumulation, triggering microcracks and affecting the integrity, impermeability, and durability of the structure.

[0006] 4. Performance Improvement Bottleneck: Simply adjusting the ratio of cement to mineral powder or selecting better aggregates (such as corundum, silicon carbide, etc.) can only improve the toughness, impact resistance and interfacial strength of materials to near their limit, making it difficult to meet the growing demand for high-performance engineering. Summary of the Invention

[0007] The purpose of this invention is to provide a basalt fiber epoxy mortar, its preparation method, and its application. This invention uses silane coupling agent-modified basalt fiber as the sole inorganic cementitious / reinforcing phase in the epoxy mortar, completely replacing cement and mineral powder in the epoxy mortar formulation. This solves the defects of traditional epoxy mortar, such as high carbon emissions, insufficient toughness, and excessive shrinkage.

[0008] To achieve the objectives of this invention, the following technical solutions are provided: A basalt fiber epoxy mortar, free of cement and mineral powder, comprises the following raw materials in parts by weight: 30-40 parts epoxy resin, 10-13 parts amine curing agent, 100-130 parts modified basalt fiber, 0-70 parts quartz sand, 0-20 parts quartz powder, 0.6-1 parts modified SiO2, and 0.1-0.3 parts dispersant; The modified basalt fiber is a silane coupling agent modified basalt fiber; the specific surface area of ​​the modified basalt fiber is ≥500 m². 2 / kg.

[0009] Preferably, the silane coupling agent is c -aminopropyltriethoxysilane or c -(2,3-epoxypropoxy)propyltrimethoxysilane; the mass of the silane coupling agent is 0.8~1.5% of the mass of the basalt fiber.

[0010] Preferably, the preparation method of the silane coupling agent modified basalt fiber includes the following steps: The silane coupling agent is atomized and sprayed into basalt fibers for mixing to obtain the silane coupling agent modified basalt fibers; the mixing is carried out under stirring conditions; the stirring rate is 300~500 r / min and the time is 15~20 min.

[0011] Preferably, the modified SiO2 is silane coupling agent surface-modified nano-SiO2 with an average particle size of 15~30 nm.

[0012] Preferably, the quartz sand is graded quartz sand with a particle size range of 0.15~0.6 mm; the fineness of the quartz powder is 200~400 mesh.

[0013] Preferably, the epoxy resin includes one or more of bisphenol A type epoxy resin, alicyclic epoxy resin, phenolic epoxy resin and bio-based epoxy resin; The epoxy value of the epoxy resin is 0.48~0.54 eq / 100g.

[0014] Preferably, the amine curing agent is one or more selected from phenolic amine curing agents, polyether amine curing agents, and alicyclic amine curing agents; The dispersant is a polycarboxylate dispersant or a phosphate ester dispersant.

[0015] This invention also provides a method for preparing the basalt fiber epoxy mortar described in the above technical solution, comprising the following steps: S1. Modified basalt fiber, quartz sand, quartz powder and SiO2 are mixed to obtain premixed dry powder; S2. Mix epoxy resin and amine curing agent to obtain resin matrix; S3. Mix the premixed dry powder and resin matrix to obtain the basalt fiber epoxy mortar.

[0016] Preferably, the mixing in step S3 is carried out under stirring conditions; including a first mixing and a second mixing performed sequentially; the stirring rate of the first mixing is 100~150 r / min and the time is 2~3 min; the stirring rate of the second mixing is 200~300 r / min and the time is 3~5 min.

[0017] The present invention also provides the application of the basalt fiber epoxy mortar described in the above technical solution or the basalt fiber epoxy mortar prepared by the preparation method described in the above technical solution in building structure reinforcement materials, building exterior walls, paving layer materials, hydraulic structures or pipeline internal protective layer materials.

[0018] Compared with the prior art, the present invention has the following beneficial effects: 1) Revolutionary low-carbon and environmentally friendly characteristics: This invention replaces all cement and mineral powder in traditional mortar with 100% modified basalt fiber powder, completely avoiding the huge carbon emissions in the production process of traditional inorganic cementitious materials. According to preliminary life cycle assessment (LCA), the carbon emissions of this material system can be reduced by more than 40% compared with traditional epoxy mortar, making it a truly green and low-carbon building material; 2) Ultra-high strength: Basalt fiber powder modified with silane coupling agent forms a strong chemical bond interface with epoxy resin, fully utilizing its high modulus properties. The filling of modified nano-SiO2 further eliminates weak areas. This results in a 7-day compressive strength of ≥110 MPa and a flexural strength of ≥70 MPa, far exceeding national standards and similar products. 3) High toughness: The residual microfiber morphology and the "pinning" effect of nano-SiO2 in basalt fiber powder can effectively bridge and deflect microcracks, consuming fracture energy. The material exhibits obvious pseudo-plasticity upon failure, rather than sudden brittle fracture, significantly improving impact resistance and fatigue resistance; 4) Extremely low drying shrinkage and high volume stability: By completely avoiding the hydration shrinkage of cement and achieving extremely high density through optimized particle size distribution (basalt fiber powder, quartz powder, nano SiO2) and strong interfacial bonding, the drying shrinkage rate of this material is controlled at an extremely low level of ≤0.5%, which greatly reduces the risk of shrinkage cracking and improves long-term durability. 5) Excellent wear resistance and erosion resistance: Basalt itself has high hardness, and the recycled basalt fiber powder is uniformly dispersed in a hard epoxy network, forming an "armor" structure with hard particles as the reinforcing phase. This structure gives the material excellent resistance to water flow and sediment erosion and mechanical wear, making it particularly suitable for harsh environments such as hydraulic flood discharge structures and mine tunnels; 6) Achieved high-value-added transformation of solid waste: This invention preferably uses recycled basalt fiber as raw material, transforming the originally low-value or even negative-value basalt fiber waste into core raw materials for preparing ultra-high-performance engineering materials through fine processing and surface functionalization, opening up a new path for the resource utilization of solid waste, with significant economic and social benefits; 7) Good construction adaptability: Through reasonable mix design and step-by-step mixing process, the resulting mortar has good workability and suitable consistency. It can be applied by hand or by machine, meeting the diverse application needs of the project site. Detailed Implementation

[0019] This invention provides a basalt fiber epoxy mortar, free of cement and mineral powder; comprising the following raw materials in parts by weight: 30-40 parts epoxy resin, 10-13 parts amine curing agent, 100-130 parts modified basalt fiber, 50-70 parts quartz sand, 10-20 parts quartz powder, 0.6-1 parts modified SiO2, and 0.1-0.3 parts dispersant; wherein the modified basalt fiber is silane coupling agent modified basalt fiber; and the specific surface area of ​​the modified basalt fiber is ≥500 m². 2 / kg.

[0020] In this invention, unless otherwise specified, all raw materials used in the preparation are commercially available products well known to those skilled in the art.

[0021] In this invention, the raw materials of the basalt fiber epoxy mortar do not contain cement or mineral powder. This invention uses silane coupling agent-modified basalt fiber as the sole inorganic cementitious / reinforcing phase in the epoxy mortar, 100% replacing cement and mineral powder in the epoxy mortar formula. This solves the defects of traditional epoxy mortar, such as high carbon emissions, insufficient toughness, and excessive shrinkage. Furthermore, this invention… In this invention, the basalt fiber epoxy mortar comprises 30-40 parts by weight of epoxy resin, which may be 31, 33, 34, 35 or 37 parts in specific embodiments; the epoxy resin comprises one or more of bisphenol A type epoxy resin, alicyclic epoxy resin, phenolic epoxy resin and bio-based epoxy resin, which may be bisphenol A type epoxy resin in specific embodiments; the epoxy value of the epoxy resin is 0.48-0.54 eq / 100g, which may be 0.49, 0.50 or 0.52 eq / 100g in specific embodiments. The alicyclic epoxy resin in this invention has excellent weather resistance due to the absence of benzene rings, making it suitable for exposed engineering projects; the multifunctional structure of phenolic epoxy resin can improve heat resistance (Tg can reach above 180℃); bio-based epoxy resins (such as rosin-based and lignin-based resins) conform to the green and low-carbon positioning and can further reduce dependence on petrochemicals; bisphenol A type epoxy resins (such as polyurethane or polyether modified resins) can improve elongation while maintaining strength, and have the best compatibility with the formulation of this invention.

[0022] In this invention, based on the weight parts of epoxy resin, the basalt fiber epoxy mortar includes 10-13 parts of amine curing agent, which may be 11 or 12 parts in specific embodiments; the amine curing agent is one or more of phenolic amine curing agent, polyether amine curing agent and alicyclic amine curing agent; specifically, the phenolic amine curing agent is T-31, the polyether amine curing agent is D-230, and the alicyclic amine curing agent is HY-951.

[0023] In this invention, the basalt fiber epoxy mortar comprises 100-130 parts by weight of modified basalt fiber, and in specific embodiments, it can be 105, 110, 120, or 125 parts; the specific surface area of ​​the modified basalt fiber is ≥500 m². 2 / kg, preferably 500~1000 m 2 / kg, which in specific embodiments can be 700 or 800 m 2 / kg; the modified basalt fiber is silane coupling agent modified basalt fiber; the silane coupling agent is c -aminopropyltriethoxysilane (KH550) or c -(2,3-epoxypropoxy)propyltrimethoxysilane (KH560); the mass of the silane coupling agent is 0.8~1.5% of the mass of the basalt fiber, and in specific embodiments it can be 0.9, 1.0, 1.1, 1.3 or 1.4%.

[0024] In this invention, the preparation method of the silane coupling agent modified basalt fiber includes the following steps: The silane coupling agent is atomized and sprayed into basalt fiber under high temperature hot pressing, and the mixture is then mixed to obtain the silane coupling agent modified basalt fiber. The mixing is carried out under stirring conditions; the stirring rate is 300~500 r / min and the time is 15~20 min; the high temperature hot pressing treatment temperature is 120~180℃, the pressure is 0.3~0.8MPa, and the time is 15~30 min.

[0025] The preparation of basalt fiber modified with silane coupling agent according to this invention is carried out in a fluidized suspension calcination device. This invention utilizes fluidized suspension technology to fully disperse and suspend the basalt fiber powder, while simultaneously introducing the coupling agent uniformly into the system in the form of a spray. Under dynamic suspension and heating conditions, the coupling agent achieves efficient hydrolysis, dispersion, and sufficient contact and reaction with the powder surface, ultimately obtaining modified regenerated basalt fiber powder. This invention involves no solvent addition during the basalt fiber modification process, avoiding side reactions; and through fluidized suspension and atomized spraying, it ensures that the coupling agent is fully hydrolyzed, vaporized, and uniformly coated with the regenerated basalt fiber powder, while avoiding powder agglomeration or thermal decomposition of the coupling agent; furthermore, high-temperature hot pressing accelerates the condensation reaction, resulting in higher grafting density, completing the process in one step without agglomeration, achieving deep processing of basalt fiber.

[0026] In this invention, the basalt fiber epoxy mortar comprises 0-70 parts of quartz sand by weight of epoxy resin, and in specific embodiments, it can be 30, 50, or 60 parts; the quartz sand is graded quartz sand with a particle size range of 0.15-0.6 mm; specifically, the graded quartz sand can be a mixture of 0.15-0.3 mm and 0.3-0.6 mm particle sizes at a mass ratio of 1:2. In this invention, quartz sand can be used as aggregate, and recycled fine aggregates such as steel slag, river sand, and marble powder can be used instead.

[0027] In this invention, the basalt fiber epoxy mortar comprises 0 to 20 parts of quartz powder, based on the weight of epoxy resin, and in specific embodiments, it can be 5, 10, or 15 parts; the fineness of the quartz powder is 200 to 400 mesh, and in specific embodiments, it can be 250 or 345 mesh.

[0028] In this invention, the raw materials of the basalt fiber epoxy mortar may not contain quartz sand and quartz powder. Instead, a highly concentrated, ultra-fine modified recycled basalt fiber powder (RBFP) and modified nano-SiO2 are used to construct an extremely dense "powder-resin" composite structure, achieving ultra-high mechanical properties while exhibiting excellent self-leveling permeability and strong adhesion to steel and concrete substrates. This material is specifically designed for high-precision, high-requirement engineering scenarios, and is particularly suitable for pressure grouting repair of fine cracks in concrete (0.1~3mm), ultra-thin (1~5mm) protection of steel structures and composite materials, and high-strength anchoring grouting for precision equipment. It achieves a perfect combination of high-value utilization of solid waste and the performance of cutting-edge engineering materials.

[0029] In this invention, based on the weight of epoxy resin, the basalt fiber epoxy mortar includes 0.6 to 1 part of SiO2, which may be 0.8 or 0.9 parts in specific embodiments; the SiO2 is silane coupling agent surface-modified nano-SiO2, which may be HL-200 in specific embodiments; the average particle size is 15 to 30 nm, which may be 20 or 24 nm in specific embodiments.

[0030] In this invention, the basalt fiber epoxy mortar includes 0.1 to 0.3 parts of dispersant based on the weight of epoxy resin; the dispersant is a polycarboxylate dispersant or a phosphate ester dispersant; specifically, the polycarboxylate dispersant is PC-40, and the phosphate ester dispersant is BYK-110.

[0031] This invention also provides a method for preparing the basalt fiber epoxy mortar described in the above technical solution, comprising the following steps: S1. Modified basalt fiber, quartz sand, quartz powder and SiO2 are mixed to obtain premixed dry powder; S2. Mix epoxy resin and amine curing agent to obtain resin matrix; S3. Mix the premixed dry powder and resin matrix to obtain the basalt fiber epoxy mortar.

[0032] This invention mixes modified basalt fiber, quartz sand, quartz powder, and SiO2 to obtain a premixed dry powder. The mixing method for the modified basalt fiber, quartz sand, quartz powder, and SiO2 in this invention is as follows: stirring and mixing at a speed of 200-400 r / min for 10-15 min in a three-dimensional mixer or conical mixer. The mixing method for the epoxy resin and amine curing agent in this invention is as follows: stirring and mixing at 60-80 r / min with a low-speed stirrer for 3-5 min to obtain a transparent resin matrix mixture. In this invention, the mixing in step S3 is carried out under stirring conditions; it includes a first mixing and a second mixing performed sequentially; the stirring rate of the first mixing is 100~150 r / min and the time is 2~3 min; the stirring rate of the second mixing is 200~300 r / min and the time is 3~5 min.

[0033] In this invention, the process also includes molding and curing the obtained basalt fiber epoxy mortar; the molding process involves vibrating the mortar in a pre-coated steel mold on a vibrating table for 30-60 seconds to remove air bubbles; the curing process is carried out under standard conditions, specifically a temperature of 20±2℃, relative humidity ≤65%, and demolding after static curing for ≥24 hours.

[0034] The present invention also provides the application of the basalt fiber epoxy mortar described in the above technical solution or the basalt fiber epoxy mortar prepared by the preparation method described in the above technical solution in building structure reinforcement materials, building exterior walls, paving layer materials, hydraulic structures or pipeline internal protective layer materials.

[0035] Specifically, this invention can be applied to building structure reinforcement materials, to the reinforcement and waterproofing, antifouling, and anti-aging protection of the exterior walls and structures of urban renewal buildings, to industrial flooring or wear-resistant paving materials, and to the anti-abrasion protective layer materials for the inner surfaces of hydraulic structures and pipelines.

[0036] To further illustrate the present invention, the following detailed description, in conjunction with embodiments, of the basalt fiber epoxy mortar provided by the present invention, its preparation method, and its application, should not be construed as limiting the scope of protection of the present invention.

[0037] Example 1 1) Raw material pretreatment and modification: Waste basalt fiber products are mechanically crushed and then ground using a ball mill to achieve a specific surface area ≥ 500 m². 2 / kg of recycled basalt fiber powder; 120 parts of recycled basalt fiber powder were placed in a fluidized suspension calcination device, and 1.2 parts of KH550 coupling agent were atomized and sprayed in under high temperature and hot pressure. The mixture was stirred and mixed at 500 r / min for 30 min to obtain modified recycled basalt fiber powder.

[0038] 2) Premixing of dry powder materials: The above-mentioned 120 parts of modified recycled basalt fiber powder, 60 parts of graded quartz sand (mixed at a mass ratio of 1:2 with particle sizes of 0.15~0.3mm and 0.3~0.6mm), 15 parts of quartz powder (325 mesh), 0.8 parts of modified nano-SiO2 (HL-200, average particle size 20nm, pretreated with KH550), and 0.2 parts of polycarboxylate high-efficiency dispersant (PC-40) were added to a three-dimensional motion mixer. The mixer speed was set to 25 r / min, and the stirring time was 15 min. After mixing, a premixed dry powder with uniform color and no lumps was obtained.

[0039] 3) Resin matrix preparation: Weigh 35 parts of epoxy resin E-51 (E-51, epoxy value 0.51eq / 100g) and 12 parts of phenolic amine curing agent T-31 into a dry 1L plastic mixing tank. Using a paddle mixer, manually stir at a speed of about 80 r / min for about 4 minutes until the mixture is clear and transparent, without any layering or flocculation.

[0040] 4) Mortar mixing: Pour the premixed dry powder obtained in step 2) into the resin matrix obtained in step 3) all at once. Fix the mixing bucket on a planetary cement mortar mixer (JJ-5 type). First stage (low-speed wetting): Start the mixer and stir at a speed of 140±5 r / min for 3 minutes to allow all powder to be initially wetted by the resin; Second stage (high-speed homogenization): Increase the mixer speed to 280±10 r / min and continue stirring for 4 minutes. Observe the mortar state until the materials are evenly mixed, have a uniform color, and exhibit a viscous paste-like consistency with good thixotropic properties. Stop stirring to obtain basalt fiber epoxy mortar.

[0041] 5) Shaping and Curing The basalt fiber epoxy mortar mixed in step 4) was poured into standard steel molds (40mm × 40mm × 160mm) coated with a thin layer of silicone grease release agent in two batches. After each filling, the molds were vibrated on a cement mortar vibrating table for 30 seconds to ensure thorough compaction and remove air bubbles. The surface was then smoothed with a scraper. The molds were placed in a standard curing room at a temperature of 20±1℃ and a relative humidity of 60±5%. After standing for 24 hours, the molds were demolded. The demolded specimens continued to be cured under the same temperature and humidity conditions for 7 days and 28 days.

[0042] Example 1: Performance test results of basalt fiber epoxy mortar after curing: 7-day compressive strength: 118.5 MPa; 7-day flexural strength: 74.2 MPa; 28-day drying shrinkage: 420×10 -6 ; Abrasion resistance (wear loss): 0.018 g / cm2 ; Impact energy (falling weight method): 12.5 J; Bond strength with old concrete: 5.8 MPa (failure occurs within the concrete itself).

[0043] Example 1: Analysis of the characteristics and applicability of basalt fiber epoxy mortar after curing: This embodiment uses a moderate amount of KH550 modified recycled basalt fiber powder, combined with the universal T-31 curing agent, to ensure excellent mechanical properties (strength far exceeding that of traditional materials) while effectively controlling material costs. It exhibits extremely low drying shrinkage, excellent wear resistance and impact resistance, and strong adhesion to concrete substrates. This formulation boasts outstanding overall performance and a stable process, making it a preferred solution for large-scale applications in structural reinforcement, repair, and high-wear-resistant industrial flooring.

[0044] Example 2 1) Raw material pretreatment and modification: Waste basalt fiber products are mechanically crushed and then ground using a ball mill to achieve a specific surface area ≥ 500 m². 2 / kg of recycled basalt fiber powder; 130 parts of recycled basalt fiber powder were placed in a fluidized suspension calcination device, and 1.56 parts of KH560 coupling agent were atomized and sprayed in under high temperature and hot pressure. The mixture was stirred and mixed at 500 r / min for 30 min to obtain modified recycled basalt fiber powder.

[0045] 2) Premixing of dry powder materials: The above-mentioned 130 parts of modified recycled basalt fiber powder, 70 parts of graded quartz sand (mixed at a mass ratio of 1:2 with particle sizes of 0.15~0.3mm and 0.3~0.6mm), 10 parts of quartz powder (400 mesh), 1.0 part of modified nano-SiO2 (HL-200, average particle size 20nm, pretreated with KH550), and 0.3 parts of polycarboxylate high-efficiency dispersant (PC-40) were added to a three-dimensional motion mixer. The mixer speed was set to 25 r / min, and the stirring time was 15min. After mixing, a premixed dry powder with uniform color and no lumps was obtained.

[0046] 3) Resin matrix preparation: Weigh 38 parts of epoxy resin E-51 (E-51, epoxy value 0.51 eq / 100g) and 13 parts of phenolic amine curing agent D-230 into a dry 1L plastic mixing tank. Using a paddle mixer, manually stir at a speed of about 80 r / min for about 4 minutes until the mixture is clear and transparent, without any layering or flocculation.

[0047] 4) Mortar mixing: Pour the premixed dry powder obtained in step 2) into the resin matrix obtained in step 3) all at once. Fix the mixing bucket on a planetary cement mortar mixer (JJ-5 type). First stage (low-speed wetting): Start the mixer and stir at a speed of 135±5 r / min for 3 minutes to allow all powder to be initially wetted by the resin; Second stage (high-speed homogenization): Increase the mixer speed to 270±10 r / min and continue stirring for 4 minutes. Observe the mortar state until the materials are evenly mixed, have a uniform color, and exhibit a viscous paste-like consistency with good thixotropic properties, then stop stirring.

[0048] Step 5) is the same as in Example 1.

[0049] Example 2: Performance test results of basalt fiber epoxy mortar after curing: 7-day compressive strength: 121.3 MPa 7-day flexural strength: 75.8 MPa 28-day drying shrinkage: 380×10 -6 ; Abrasion resistance (wear loss): 0.016 g / cm 2 ; Impact energy (falling weight method): 13.1 J; Bond strength with old concrete: 6.0 MPa (failure occurs within the concrete itself).

[0050] Example 2: Analysis of the characteristics and applicability of basalt fiber epoxy mortar after curing: This embodiment achieves "ultra-high strength and toughness" through three optimizations: First, it uses KH560 coupling agent, whose terminal epoxy groups can form more direct covalent bonds with epoxy resin, resulting in a stronger interface; second, it increases the amount of high-modulus recycled basalt fiber powder (130 parts), further strengthening the composite material skeleton; and third, it selects the more flexible polyetheramine curing agent D-230, improving the deformation capacity of the resin matrix itself. Test results show that its strength, toughness, and crack resistance (reflected in the minimum shrinkage rate) all reach the highest level. This formulation is particularly suitable for applications with stringent requirements for material performance, such as seismic reinforcement of bridges, emergency repair of heavy-duty traffic roads, anti-erosion and abrasion protection layers for hydropower station spillway gates, and military facilities.

[0051] Example 3 1) Raw material pretreatment and modification: Waste basalt fiber products are mechanically crushed and then ground using a ball mill to achieve a specific surface area ≥800 m². 2 / kg (D50 approximately 5μm) of regenerated basalt fiber powder; 150 parts of regenerated basalt fiber powder were placed in a fluidized bed calcination apparatus, and 2.25 parts of KH560 coupling agent were mixed with an appropriate amount of ethanol; KH560 coupling agent was atomized and sprayed in under high temperature and hot pressing conditions, and stirred and mixed at 500 r / min under vacuum conditions (-0.08 MPa) for 30 min to obtain modified regenerated basalt fiber powder.

[0052] 2) Premixing of dry powder materials: 150 parts of modified recycled basalt fiber powder, 1.5 parts of modified nano-SiO2 (HL-200, average particle size 20nm, pretreated with KH550), and 1 part of dispersant (BYK-110) were added to a three-dimensional motion mixer. The mixer speed was set to 25 r / min, and the stirring time was 15 min. After mixing, a premixed dry powder with uniform color and no lumps was obtained.

[0053] 3) Resin matrix preparation: Weigh 40 parts of epoxy resin E-51 (E-51, epoxy value 0.51 eq / 100g) and 12 parts of phenolic amine curing agent HY-951 into a dry 1L plastic mixing bowl. Using a paddle mixer, manually stir at a speed of about 80 r / min for about 4 minutes until the mixture is clear and transparent, without any layering or flocculation.

[0054] 4) Mortar mixing: Pour the premixed dry powder obtained in step 2) into the resin matrix obtained in step 3) all at once. Fix the mixing bucket on a planetary cement mortar mixer (JJ-5 type). First stage (low-speed wetting): Start the mixer and stir at a speed of 145±5 r / min for 3 minutes to allow all powder to be initially wetted by the resin; Second stage (high-speed homogenization): Increase the mixer speed to 290±10 r / min and continue stirring for 4 minutes. Observe the mortar state until the materials are evenly mixed, have a uniform color, and exhibit a viscous paste-like consistency with good thixotropic properties, then stop stirring.

[0055] Step 5) is the same as in Example 1.

[0056] Example 3: Performance test results of basalt fiber epoxy mortar after curing: 7-day compressive strength: 135.6 MPa 7-day flexural strength: 82.4 MPa 28-day drying shrinkage rate: 280×10 -6 ; Abrasion resistance (wear loss): 0.020 g / cm 2 ; Impact energy (falling weight method): 11.4 J; Bond strength with old concrete: 5.5 MPa (failure occurs within the concrete itself).

[0057] Example 3: Analysis of the characteristics and applicability of basalt fiber epoxy mortar after curing: This embodiment is a "crushless" high-performance epoxy composite material completely different from aggregate-containing mortar systems. Its core feature lies in the removal of quartz sand / powder and the use of ultra-high dosage, ultra-fine modified recycled basalt fiber powder (RBFP) and nano-SiO2 to construct an extremely dense "powder-resin" composite structure. After removing coarse aggregate, it achieves a balance between self-leveling and ultra-high mechanical properties. Simultaneously, it achieves ultra-high mechanical properties (7-day compressive strength >135MPa, flexural strength >82MPa) and extremely low shrinkage (<300×10⁻⁶). -6 This material possesses excellent self-leveling permeability and extremely strong adhesion to steel and concrete substrates. Designed for high-precision, high-requirement engineering applications, it is particularly suitable for pressure grouting repair of fine cracks (0.1~3mm) in concrete, ultra-thin (1~5mm) protection of steel structures and composite materials, and high-strength anchoring grouting and high-strength adhesives for precision equipment. It achieves a perfect combination of high-value utilization of solid waste and cutting-edge engineering material performance.

[0058] Example 3 of this invention expands the application boundaries of this invention, proving that the modified RBFP system can not only be used to prepare high-strength mortar, but also, through refined design, can be used to prepare aggregate-free grouting and protective materials with even more extreme performance indicators, further highlighting the core value and application potential of recycled basalt fiber powder as a high-performance filler.

[0059] Comparative Example 1 1) Add 35 parts cement (PO 42.5 grade), 85 parts mineral powder, 60 parts graded quartz sand (mixed at a mass ratio of 1:2, with particle sizes of 0.15~0.3mm and 0.3~0.6mm), 15 parts quartz powder (325 mesh), 0.8 parts modified nano-SiO2 (HL-200, average particle size 20nm, pretreated with KH550), and 0.2 parts polycarboxylate high-efficiency dispersant (PC-40) to a three-dimensional motion mixer. Set the mixer speed to 25 r / min and the stirring time to 15 min. After mixing, a premixed dry powder with uniform color and no lumps is obtained.

[0060] 2) Resin matrix preparation: Weigh 35 parts of epoxy resin E-51 (E-51, epoxy value 0.51eq / 100g) and 12 parts of phenolic amine curing agent T-31 into a dry 1L plastic mixing tank. Using a paddle mixer, manually stir at a speed of about 80 r / min for about 4 minutes until the mixture is clear and transparent, without any layering or flocculation.

[0061] 4) Mortar mixing: Pour the premixed dry powder obtained in step 1) into the resin matrix obtained in step 2) all at once. Fix the mixing bucket on a planetary cement mortar mixer (JJ-5 type). First stage (low-speed wetting): Start the mixer and stir at a speed of 140±5 r / min for 3 minutes to allow all powder to be initially wetted by the resin; Second stage (high-speed homogenization): Increase the mixer speed to 280±10 r / min and continue stirring for 4 minutes. Observe the mortar state until the materials are evenly mixed, have a uniform color, and exhibit a viscous paste-like consistency with good thixotropic properties. Stop stirring to obtain traditional cement epoxy mortar.

[0062] 5) Shaping and Curing The traditional cement-epoxy mortar mixed in step 3) was poured into a standard 40mm×40mm×160mm steel mold coated with a thin layer of silicone grease release agent in two batches. After each filling, the mold was vibrated on a cement mortar vibrating table for 30 seconds to ensure thorough compaction and remove air bubbles. The surface was smoothed with a scraper. The mold was placed in a standard curing room with a temperature of 20±1℃ and a relative humidity of 60±5%. After standing for 24 hours, the mold was removed. The demolded specimens continued to be cured under the same temperature and humidity conditions for 7 days and 28 days.

[0063] Performance test results of traditional cement-epoxy mortar after curing in Comparative Example 1: 7-day compressive strength: 89.6 MPa; 7-day flexural strength: 46.2 MPa; 28-day drying shrinkage rate: 0.89% (i.e., 8900 × 10⁻⁶) -6 ); Pull-out strength at the concrete interface: 3.8 MPa (failure occurs at the interface). Abrasion resistance (wear loss): 0.035 g / cm 2 ; Impact resistance (falling hammer method): 6.8J.

[0064] Comparative Example 2 1) Raw material pretreatment and modification: Waste basalt fiber products are mechanically crushed and then ground using a ball mill to achieve a specific surface area ≥ 500 m². 2 / kg of recycled basalt fiber powder.

[0065] 2) Premixing of dry powder materials: The above-mentioned 120 parts of recycled basalt fiber powder, 60 parts of graded quartz sand (mixed at a mass ratio of 1:2, with particle sizes of 0.15~0.3mm and 0.3~0.6mm), 15 parts of quartz powder (325 mesh), 0.8 parts of modified nano-SiO2 (HL-200, average particle size 20nm, pretreated with KH550), and 0.2 parts of polycarboxylate high-efficiency dispersant (PC-40) were added to a three-dimensional motion mixer. The mixer speed was set to 25 r / min, and the stirring time was 15 min. After mixing, a premixed dry powder with uniform color and no lumps was obtained.

[0066] Steps 3)-5) are the same as in Example 1.

[0067] Performance test results of unmodified basalt fiber epoxy mortar after curing in Comparative Example 2: 7-day compressive strength: 103.7 MPa; 7-day flexural strength: 58.3 MPa; 28-day drying shrinkage: 0.31% (i.e., 3,100 × 10⁻⁶) -6 ); Pull-out strength at the concrete interface: 4.2 MPa (failure occurs at the interface); Abrasion resistance (wear loss): 0.028 g / cm 2 ; Impact resistance (falling hammer method): 8.5 J.

[0068] Comparative Example 3 1) Raw material pretreatment and modification: Waste basalt fiber products are mechanically crushed and then ground using a ball mill to achieve a specific surface area ≥ 500 m². 2 / kg of recycled basalt fiber powder; 120 parts of recycled basalt fiber powder were placed in a fluidized suspension calcination device, and 1.2 parts of KH550 coupling agent were atomized and sprayed in under high temperature and hot pressure. The mixture was stirred and mixed at 500 r / min for 30 min to obtain modified recycled basalt fiber powder.

[0069] 2) Premixing of dry powder materials: The above-mentioned 60 parts of modified recycled basalt fiber powder, 20 parts of cement (PO 42.5 grade), 40 parts of mineral powder, 60 parts of graded quartz sand (mixed at a mass ratio of 1:2 with particle sizes of 0.15~0.3mm and 0.3~0.6mm), 15 parts of quartz powder (325 mesh), 0.8 parts of modified nano-SiO2 (HL-200, average particle size 20nm, pretreated with KH550), and 0.2 parts of polycarboxylate high-efficiency dispersant (PC-40) were added to a three-dimensional motion mixer. The mixer speed was set to 25 r / min, and the stirring time was 15 min. After mixing, a premixed dry powder with uniform color and no lumps was obtained.

[0070] Steps 3)-5) are the same as in Example 1.

[0071] Performance test results of epoxy mortar with basalt fiber partially replacing cement after curing (Comparative Example 3): 7-day compressive strength: 102.6 MPa; 7-day flexural strength: 62.4 MPa; 28-day drying shrinkage rate: 0.056% (560×10⁻⁶) -6 ); Abrasion resistance (wear loss): 0.022 g / cm 2 ; Impact energy (falling hammer method): 10.2 J; Bond strength with old concrete: 4.9 MPa (failure occurs in the concrete itself).

[0072] As can be seen from the results of Comparative Examples 1-3, the 7-day compressive strength (118.5 MPa), flexural strength (74.2 MPa), and bond strength (5.8 MPa) of the basalt fiber epoxy mortar obtained in Example 1 of the present invention are significantly better than those of the traditional system (65-80 MPa, 30-45 MPa, and 3.5-4.5 MPa, respectively), while the drying shrinkage rate (0.042%) is much lower than that of the traditional system (0.08%-0.12%).

[0073] Although the above embodiments have provided a detailed description of the present invention, they are only some embodiments of the present invention, and not all embodiments. People can obtain other embodiments based on these embodiments without creative effort, and these embodiments all fall within the protection scope of the present invention.

Claims

1. A basalt fiber epoxy mortar, characterized in that, Free of cement and mineral powder; The raw materials include the following parts by weight: 30-40 parts epoxy resin, 10-13 parts amine curing agent, 100-130 parts modified basalt fiber, 0-70 parts quartz sand, 0-20 parts quartz powder, 0.6-1 parts modified SiO2, and 0.1-0.3 parts dispersant; The modified basalt fiber is a silane coupling agent modified basalt fiber; The modified basalt fiber has a specific surface area ≥ 500 m². 2 / kg.

2. The basalt fiber epoxy mortar according to claim 1, characterized in that, The silane coupling agent is γ -aminopropyltriethoxysilane or γ -(2,3-epoxypropoxy)propyltrimethoxysilane; The mass of the silane coupling agent is 0.8 to 1.5% of the mass of the basalt fiber.

3. The basalt fiber epoxy mortar according to claim 1 or 2, characterized in that, The preparation method of the silane coupling agent modified basalt fiber includes the following steps: The silane coupling agent is atomized and sprayed into basalt fibers and mixed to obtain the silane coupling agent modified basalt fibers. The mixing is carried out under stirring conditions; the stirring rate is 300~500 r / min, and the time is 15~20 min.

4. The basalt fiber epoxy mortar according to claim 1, characterized in that, The modified SiO2 is silane coupling agent surface-modified nano-SiO2 with an average particle size of 15~30 nm.

5. The basalt fiber epoxy mortar according to claim 1, characterized in that, The quartz sand is graded quartz sand with a particle size range of 0.15~0.6 mm; the fineness of the quartz powder is 200~400 mesh.

6. The basalt fiber epoxy mortar according to claim 1, characterized in that, The epoxy resin includes one or more of bisphenol A type epoxy resin, alicyclic epoxy resin, phenolic epoxy resin and bio-based epoxy resin; The epoxy value of the epoxy resin is 0.48~0.54 eq / 100g.

7. The basalt fiber epoxy mortar according to claim 1, characterized in that, The amine curing agent is one or more of phenolic amine curing agents, polyether amine curing agents, and alicyclic amine curing agents; The dispersant is a polycarboxylate dispersant or a phosphate ester dispersant.

8. The method for preparing basalt fiber epoxy mortar according to any one of claims 1 to 7, characterized in that, Includes the following steps: S1. Modified basalt fiber, quartz sand, quartz powder and SiO2 are mixed to obtain premixed dry powder; S2. Mix epoxy resin and amine curing agent to obtain resin matrix; S3. Mix the premixed dry powder and resin matrix to obtain the basalt fiber epoxy mortar.

9. The preparation method according to claim 8, characterized in that, The mixing described in step S3 is carried out under stirring conditions; it includes a first mixing and a second mixing performed sequentially; the stirring rate of the first mixing is 100~150 r / min and the time is 2~3 min; the stirring rate of the second mixing is 200~300 r / min and the time is 3~5 min.

10. The application of the basalt fiber epoxy mortar according to any one of claims 1 to 7 or the basalt fiber epoxy mortar prepared by the preparation method according to claim 8 or 9 in building structure reinforcement materials, building exterior walls, paving layer materials, hydraulic structures or pipeline internal protective layer materials.