Ultra-thin color paving material for steel structure pedestrian bridge deck and preparation method thereof

Abstract

The application discloses a kind of ultra-thin color paving materials for steel structure pedestrian bridge deck and preparation method thereof, relate to engineering material field, a kind of ultra-thin color paving materials for steel structure pedestrian bridge deck, the paving material integrally formed, and from top to bottom successively include cover layer, skid-resistant wear-resistant layer and primer, the skid-resistant wear-resistant layer uses modified water-based epoxy resin mortar, the paving material in the application.The ultra-thin color paving material for steel structure pedestrian bridge deck proposed in the application uses water-based epoxy resin mortar as skid-resistant wear-resistant layer, and is integrally formed by multiple layers of material combination, meets the requirements of temperature deformation and waterproofing and corrosion prevention of steel bridge deck, and the pendulum friction coefficient in skid index is not less than 70BPN, paving sand method pavement structure depth index is between 0.7mm to 1.2mm, and has excellent anti-aging and color retention performance, can be applied to pedestrian steel bridge and bicycle exclusive lane steel bridge and other light-load traffic steel bridge deck paving.

Description

Technical Field

[0001] This invention relates to the field of engineering materials, specifically to an ultra-thin colored paving material for steel structure pedestrian bridge decks and its preparation method. Background Technology

[0002] The development of steel structure bridges has greatly solved the problem of the heavy weight of long-span bridges and promoted the development of bridge engineering. To adapt to the temperature deformation and waterproofing / corrosion protection requirements of steel bridge decks, the pavement layer generally uses concrete materials with good flexibility, such as polymer cement concrete, cast-in-place asphalt concrete, and high-performance asphalt concrete. In recent years, to improve aesthetics and further reduce weight, structural combinations such as colored asphalt concrete and asphalt concrete / cement concrete + colored anti-skid surface layer have been adopted.

[0003] Polymer thin-layer paving is commonly used for pedestrian and lightly loaded steel bridge decks. It primarily enhances the overall aesthetics and landscape of the bridge, and possesses excellent co-deformation capabilities. It can be installed at room temperature, requiring less sophisticated construction machinery than asphalt concrete and cement concrete, and allows for shorter traffic opening times. More importantly, polymer thin-layer paving reduces seepage on steel bridge decks, preventing corrosion and subsequent detachment of the pavement structure. Extensive practical experience shows that the thickness of polymer anti-skid thin layers for pedestrian or lightly loaded steel bridge decks in my country is generally 4 mm to 6 mm, while internationally it is typically 3 / 8 inch ≈ 9.5 mm. Table 1 summarizes several commonly used steel bridge deck paving methods and practical examples.

[0004] Table 1: Domestic and International Application Cases of Polymer Pavement for Steel Bridge Deck

[0005] Because colored anti-skid thin layers play an important role in shaping bridge surface landscapes, improving regional thermal environments, and increasing cycling comfort and safety, polymer thin-layer colored paving systems have become a research hotspot in the road industry, with continuous efforts to improve the road performance of anti-skid thin layers. However, the road performance of polymer resin materials using a single system has shortcomings. Table 2 summarizes the advantages and disadvantages of three types of polymer resins.

[0006] Table 2: Materials for Thin-Layer Pavement Systems

[0007] Based on the basic binder system, researchers both domestically and internationally have widely adopted chemical modification and structural layer optimization techniques to improve the road performance of polymer thin-layer pavement systems. Ewa et al. prepared colored composite resin polymers with good mechanical and anti-corrosion properties by mixing pigments with acrylic resin and epoxy resin in a certain proportion. Lewis et al. and Virgawati et al. prepared composite resins modified with nano-oxides, exhibiting excellent thermal stability and corrosion resistance. Domestic researchers Chen Wei et al. prepared composite epoxy resin materials by modifying shell powder, improving stability. Dong Guangchuo et al. prepared anti-skid thin-layer binders using methacrylic acid resin, exhibiting excellent colorability, low-temperature crack resistance, and corrosion resistance. Gu Yafeng et al. compared commonly used thin-layer pavement system materials and concluded that methyl methacrylate is most suitable for thin-layer pavement of steel bridge decks, with excellent construction performance and significant economic advantages. Fang Xing et al. used epoxy resin and single-size crushed stone to form thin layers, exhibiting good fatigue and crack resistance. Chen Jie et al. conducted a defect investigation on the steel bridge deck pavement of the Xiamen Sky Bike Expressway. The pavement consists of a 1mm solvent-free adhesive base, a 6mm resin intermediate wear-resistant layer, a 1mm resin wear-resistant and anti-slip surface layer, and an anti-UV coating. The results showed that the overall performance of the steel bridge deck pavement was good, with few serious surface cracking and delamination / peeling defects. Surface water accumulation and stains were the main problems. On-site tensile strength testing revealed that the interface between the wear-resistant layer and the surface colored thin layer was the weakest point in the pavement structure, easily leading to delamination and peeling.

[0008] Waterborne epoxy resin systems are green, environmentally friendly, and designable polymer binders with excellent properties such as high elasticity, corrosion resistance, wear resistance, impermeability, resistance to light radiation, strong adhesion, and adjustable hardness. Epoxy resin mortar is a polymer mortar that uses epoxy resin polymer materials to bond sand into a whole. The cured epoxy resin material is a three-dimensional cross-linked network structure polymer with high bonding performance and thermal stability. Compared to polyurethane mortar, it has significant advantages in bonding performance, anti-slip performance, wear resistance, and durability. Furthermore, because waterborne epoxy resin itself contains a certain amount of free water, it is necessary to add an anti-corrosion primer layer to the epoxy resin mortar, which serves as an anti-slip surface layer, to ensure corrosion resistance, impermeability, and adhesion. Since epoxy resin has poor weather resistance and will change color after a period of time, it is necessary to add a topcoat layer to improve color retention and anti-aging properties, reducing or delaying surface damage. Summary of the Invention

[0009] This invention provides an ultra-thin colored paving material for steel structure pedestrian bridge decks and its preparation method. The technical problem to be solved is that the existing pedestrian steel bridge deck paving has poor anti-slip and wear resistance, poor color retention, and low waterproof and anti-corrosion performance.

[0010] This invention is achieved through the following technical solution: This application proposes an ultra-thin colored paving material for steel structure pedestrian bridge decks. The paving material is integrally formed and includes, from top to bottom, a topcoat layer, an anti-slip and wear-resistant layer, and a base coat layer. The anti-slip and wear-resistant layer is made of modified water-based epoxy resin mortar.

[0011] Preferably, the water-based epoxy resin mortar is composed of aggregates and binders, wherein the binder accounts for 10-20% of the mass of the aggregates, and the aggregates are colored aggregates formed by sintering rock particles and pigments, wherein the rock particles are one or more combinations of basalt, limestone, granite, and quartzite.

[0012] Preferably, the aggregate has a particle size of 0.075 mm - 1.18 mm, wherein the aggregate with a particle size of 0.075 mm - 0.15 mm accounts for 20% - 30% of the total aggregate mass, the aggregate has a soundness of ≤12%, and a sand equivalent of ≥60%.

[0013] Preferably, the binder comprises two components, A and B. Component A is a mixture of acrylic resin hybrid waterborne epoxy resin and color paste, and component B is composed of aliphatic polyamine and nanofiller. The mass ratio of component A to component B is 2:1-3.5:1.

[0014] Preferably, the nanofiller accounts for 5% to 8% of the mass percentage of component B, the acrylic resin accounts for 10% to 15% of the mass percentage of component A, the weight ratio of the waterborne epoxy resin to the aggregate is 1:2.5 to 1:3, the color paste is a waterborne inorganic color paste, the coloring rate of the color paste is greater than 98%, and the color paste accounts for 1% to 5% of the mass percentage of component A.

[0015] Preferably, the cover layer is a mixture of methacrylic resin and nano anti-aging agent, wherein the nano anti-aging agent accounts for 1% to 3% of the total weight of the cover layer.

[0016] Preferably, the base coating is a methyl methacrylate primer or an epoxy zinc-rich primer. The methyl methacrylate primer includes methyl methacrylate and pure water, and the epoxy zinc-rich primer includes epoxy resin, zinc powder and curing agent. The mass ratio of epoxy resin to curing agent is 10:1, and the zinc powder accounts for 60% to 65% of the mass of the base coating.

[0017] Preferably, the total thickness of the anti-slip and wear-resistant layer is 4-6 mm, the anti-slip and wear-resistant layer is formed by stacking at least two layers, and the thickness of the base layer is 50 μm-150 μm.

[0018] This invention also provides a method for preparing an ultrathin colored paving material for steel structure pedestrian bridge decks, comprising the following steps: S1: The steel bridge deck is rust-removed, ground and shot-blasted. The cleanliness after treatment reaches Sa2.5 level and the roughness reaches 50μm ~100μm. Then, methyl methacrylate primer or epoxy zinc-rich primer is sprayed onto the treated steel bridge deck. After surface drying and hardening, the base coating is obtained. S2: Modified water-based epoxy resin mortar is first applied to the surface of the base coating using the mortar method, and then applied by spraying or scraping. After curing, an anti-slip and wear-resistant layer is obtained by bonding to the base coating. S3: Apply a mixture of methacrylic resin and nano anti-aging agent to cover the anti-slip and wear-resistant layer, and obtain a topcoat layer after surface drying.

[0019] Preferably, the spraying rate per unit area during spraying in S1 is 0.4 kg / m². 2 -0.5kg / m 2 The surface drying time is ≤30 minutes, the surface drying temperature is 20℃-30℃, and the water absorption rate is ≤0.3%; the construction time in S2 is greater than 0.5 hours, until the adhesion strength of the obtained anti-slip and wear-resistant layer to the base layer is ≥5 MPa after curing; the amount of topcoat material used in S3 is 0.15 kg / m². 2 -0.25kg / m 2 .

[0020] Specifically, this invention provides an ultra-thin colored paving material for steel structure pedestrian bridge decks and its preparation method, comprising, from top to bottom, a topcoat layer, an anti-slip and wear-resistant layer, a base coat layer, and a steel bridge deck. The base coat layer can be made from methyl methacrylate or epoxy zinc-rich paint; the anti-slip and wear-resistant layer is made from water-based epoxy resin and colored sand; and the topcoat layer is made from methyl methacrylate and a nano-anti-aging agent.

[0021] The typical characteristics of steel bridge decks are that they are made of Q235 low-carbon steel, bear dynamic loads from pedestrians and non-motorized vehicles, and the steel plate surfaces undergo rust removal, grinding, and shot blasting treatments. The cleanliness requirement after treatment is Sa2.5 grade, and the roughness is 50μm~100μm.

[0022] The primer coating is characterized by strong anti-corrosion and waterproof sealing properties, and is composed of either methyl methacrylate or epoxy zinc-rich paint. The methyl methacrylate primer mainly consists of methyl methacrylate and pure water, while the epoxy zinc-rich paint mainly consists of epoxy resin, zinc powder, and a curing agent. The ratio of epoxy resin to curing agent is 10:1, and the zinc powder content is 60%~65%. The shear strength of the bonding interface between the primer coating and the steel plate surface is not less than 1.5 MPa, and the pull-out strengths of the methyl methacrylate primer and the epoxy zinc-rich primer are not less than 5 MPa and 7 MPa, respectively. The primer coating is prepared by mixing, spraying, and hardening the raw materials; the thickness of the primer coating is 50-150 μm; preferably, the spraying rate per unit area of ​​the primer coating is 0.4-0.5 kg / m². 2 The raw materials are used after being stirred evenly. The surface drying time (25℃) is ≤20 minutes, the water absorption rate is ≤0.3%, and it has the properties of being impermeable, corrosion resistant and waterproof.

[0023] The anti-slip and wear-resistant layer is characterized by the following: the colored epoxy resin mortar is composed of aggregates and water-based epoxy resin binder, wherein the water-based epoxy resin binder accounts for 10-20% of the aggregate mass. The aggregates can be one or more combinations of basalt, limestone, granite, and quartzite, with fine aggregate particle size of 0.075-1.18 mm (200 mesh-16 mesh), soundness ≤12%, sand equivalent ≥60%, and sintered with pigments to form colored fine aggregates. Preferably, the aggregates with a particle size of 0.075 mm-0.15 mm have a hydrophilicity coefficient <0.6, a plasticity index <4%, and account for 20%-30% of the total aggregate mass. The weight ratio of water-based epoxy resin to aggregates is 1:2.5 to 1:3.0, the total thickness is 4-6 mm, and it is formed in at least two layers. The lower layer can be applied using the mortar method, and the upper layer can be applied by spraying or scraping. The application time is greater than 0.5 hours, and the adhesion strength of the base coating after curing is not less than 5 MPa.

[0024] The waterborne epoxy resin binder is characterized by comprising components A and B. Component A consists of an acrylic resin hybrid waterborne epoxy resin and a colorant, with the acrylic resin accounting for 10%–15% of the total mass of component A. The colorant is a waterborne inorganic colorant with a coloring rate of 98–102%, accounting for 1%–5% of the total mass of component A. Component B consists of highly reactive curing agents such as aliphatic polyamines, ethylenediamine, hexamethylenediamine, diethylenetriamine, triethylenetetramine, and diethylaminopropylamine, meeting the requirements for room temperature curing. Nanoscale fillers such as nano-titanium dioxide, nano-montmorillonite, and nano-zinc oxide are added to component B to provide ultraviolet scattering and improve weather resistance. The proportion of nano-fillers in component B is 5–8%. The ratio of components A to B is 2:1–3.5:1, which can be selected according to the ambient temperature.

[0025] The topcoat layer is characterized by being composed of methacrylic resin and nano-anti-aging agents. Methacrylic acid is a liquid solvent, and the nano-fillers include nano-titanium dioxide, nano-montmorillonite, and nano-zinc oxide, which act as ultraviolet scatterers, improving weather resistance. These nano-fillers comprise 1% to 3% of the total weight of the topcoat layer. This enhances the UV resistance and colorfastness of the anti-slip layer.

[0026] Compared with the prior art, the embodiments of the present invention have the following advantages and beneficial effects: the ultra-thin colored paving material for steel structure pedestrian bridges proposed in the present invention has a pendulum friction coefficient of not less than 70BPN in the anti-skid index, a pavement construction depth index of 0.7mm to 1.2mm in the sand-paving method, and has excellent anti-aging and color retention properties. It can be applied to the paving of light-load traffic steel bridge decks such as pedestrian steel bridges and bicycle lane steel bridges. Attached Figure Description

[0027] To more clearly illustrate the technical solutions of the exemplary embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly described below. It should be understood that the following drawings only show some embodiments of the present invention and should not be considered as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort. In the drawings: Figure 1 This is a schematic diagram of the colored thin-layer pavement structure of a rigid pedestrian bridge deck in an embodiment of the present invention.

[0028] The labels and corresponding structural layer names in the attached diagram are as follows: 1-Steel bridge deck, 2-Base coating, 3-First anti-slip and wear-resistant layer, 4-Second anti-slip and wear-resistant layer, 5-Topcoat layer. Detailed Implementation

[0029] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are some embodiments of the present invention, but not all embodiments.

[0030] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.

[0031] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0032] This invention provides a method for preparing an ultrathin colored paving material for steel structure pedestrian bridge decks, comprising the following steps: (1) Rust removal, grinding and shot blasting treatment of the lower layer steel bridge deck. Construction waste, loose particles, etc. are cleaned up. Use a blower to blow away loose particles, dust, water, etc. that cannot be removed from the surface. Oil stains are cleaned with detergent. The cleanliness after treatment reaches Sa2.5 level and the roughness reaches 50μm ~100μm; (2) Use an electric mixer to mix the epoxy zinc-rich paint evenly and spread it on the pre-set construction area. The dosage is 0.4kg-0.5kg per square meter; or use an electric mixer to mix the methyl methacrylate primer thoroughly and apply it by manual spraying or scraping. The dosage is 0.4kg-0.5kg per square meter. (4) After the epoxy zinc-rich primer or methyl methacrylate primer has cured and passed the test, before the water-based epoxy resin mortar is laid, the surface soil and debris should be thoroughly removed by manual sweeping or blower blowing. A truck-mounted mixer was used to mix the water-based epoxy resin binder and colored sand on-site at room temperature. The ratio of components A and B was 2:1-3.5:1. The discharge rates of each component binder and aggregate were strictly checked and recorded. A screw pump was used to spray the water-based epoxy resin mortar onto the substrate. The spraying process was slow, uniform, continuous, and uninterrupted, with any clumps of mortar being removed promptly. After the substrate was completely covered and dried for 6 hours (25℃), subsequent construction could proceed. (5) Repeat step (4) to spray the second layer of wear-resistant and anti-slip surface layer. The spraying direction is opposite to that in step 4 to ensure uniformity of spraying. The spraying should be of uniform thickness and completely cover the substrate without obvious joint marks. After drying for 6 hours (25℃), proceed to the next step of construction. (6) After the modified waterborne epoxy resin mixture has cured for 6 hours, a topcoat of the surface colored mortar is applied using a high-pressure airless spraying method. The amount of topcoat material used is 0.15 kg / m². 2 -0.25kg / m 2 The coating should be applied evenly with no obvious seams, completely covering the road surface without any omissions, ultimately achieving the desired result. Figure 1 The illustrated colored thin-layer pavement structure of the rigid pedestrian bridge deck includes, from top to bottom, a topcoat layer 5, a second anti-slip and wear-resistant layer 4, a first anti-slip and wear-resistant layer 3, and a base coat 2. The entire pavement material is placed on top of the steel bridge deck 1. After construction is completed, all construction debris and garbage will be cleaned up, and the bridge will be opened to traffic after 6 hours of curing at 25°C.

[0033] Example 1: The ultra-thin colored paving material for steel structure pedestrian bridge decks prepared by the above method was applied to a 12mm thick steel bridge deck. The base coating was an epoxy zinc-rich primer with a thickness of 50μm and a spraying rate of 0.4kg / m². 2 The surface drying temperature is 20℃, the surface drying time is ≤15 min, the zinc powder accounts for 60-65% of the mass of the primer, and the resulting primer has a water absorption rate of 0.1% (test method: GB / T 1034, technical requirement: ≤0.3%), a bonding strength between the primer and the steel bridge deck of 7MPa (test method: JTG / T3364-02-2019 Appendix D, technical requirement: ≥5 MPa) and is impermeable to water (test method: GB / T 16777). Alternatively, the base coating can be methyl methacrylate, with a thickness of 100 μm and a spraying rate of 0.5 kg / m³. 2 The surface drying temperature is 20℃-30℃, and the surface drying time is ≤15 min, resulting in a base coating with a water absorption rate of 0.1% (test method: GB / T 1034, technical requirement: ≤0.3%), a bonding strength with the steel bridge deck of 6MPa (test method: JTG / T3364-02-2019 Appendix D, technical requirement: ≥5MPa), a tensile strength of 15MPa (test method: GB / T 16777, technical requirement: ≥12MPa), and water impermeability (test method: GB / T 16777). The anti-slip and wear-resistant layer is a modified water-based epoxy resin colored mortar with a thickness of 5 mm; the water-based epoxy resin binder accounts for 20% of the total mortar weight. Component A consists of acrylic resin-modified water-based epoxy resin and red color paste, with acrylic resin accounting for 10% of the weight of component A, color paste accounting for 5% of the weight of component A, and the remainder being water-based epoxy resin. Component B consists of ethylenediamine and nanofillers, with the nanofillers accounting for 5% of the weight of component B. The ratio of components A to B is 3:1, i.e., 75 parts of component A and 25 parts of component B are mixed. The technical indicators of the water-based epoxy resin binder of this embodiment were tested, and the test results are shown in Table 3. Table 3 Technical Specifications of Waterborne Epoxy Resin Cementitious Materials

[0034] The aggregate used is colored manufactured sand with a particle size of 0.15-1.18 mm, and the parent rock of the manufactured sand is quartzite. Aggregates with a particle size of 0.075 mm-0.15 mm account for 25% of the total aggregate mass, and the binder accounts for 16% of the aggregate mass. The test results of the aggregate technical indicators are shown in Table 4. The aggregate is sintered with red natural color powder to produce red colored sand.

[0035] Table 4 Test Results of Fine Aggregate Technical Indicators

[0036] During construction, a method of mixing once and paving multiple times is adopted to control the overall flatness. The lower coating is applied using the mortar method, and the upper coating is applied using the scraper method.

[0037] The topcoat layer is made of nano-modified methacrylic resin, with a spraying rate of 0.2 kg / m². 2 The coating consists of methacrylic resin and nano zinc oxide filler, with the nano zinc oxide filler accounting for 1% of the total mass of the topcoat. The topcoat material meets the technical requirements of JT / T712-2008 "Road Anti-skid Coating".

[0038] Example 2: The difference between this example and Example 1 is that a 6mm anti-slip and wear-resistant layer is used, and the binder accounts for 16% of the aggregate mass.

[0039] Example 3: The difference between this example and Example 1 is that a 4mm anti-slip and wear-resistant layer is used, and the binder accounts for 17% of the aggregate mass.

[0040] Performance evaluation of steel bridge deck pavement structure: The performance of water-based epoxy resin colored thin film on steel bridge deck was examined through four evaluation indicators: impermeability, anti-skid performance, anti-aging performance, and interlayer bonding performance.

[0041] It should be noted that: Evaluation of seepage prevention performance: The seepage prevention performance of waterborne epoxy resin thin-layer overlay structure is evaluated by the permeability coefficient. The evaluation method follows the permeability coefficient test method in JTG 3450-2019 "Specifications for Field Testing of Highway Subgrade and Pavement".

[0042] Anti-skid performance evaluation: The anti-skid performance of waterborne epoxy resin thin film was evaluated using a pendulum friction coefficient tester. The evaluation method was in accordance with the pendulum friction coefficient method in JTG 3450-2019 "Specifications for Field Testing of Highway Subgrade and Pavement".

[0043] Anti-aging performance evaluation: The color of the paving layer before and after aging was compared using an artificial climate aging chamber (mercury lamp method). Comparison was also made using a standard color chart.

[0044] Evaluation of interlayer bonding performance: The interlayer bonding performance of waterborne epoxy resin thin-layer structures was tested according to the test methods for bonding strength of steel bridge deck pavement (Appendix D) and shear strength of steel bridge deck pavement (Appendix E) as described in JTG / T3364-02-2019 "Technical Specification for Design and Construction of Highway Steel Bridge Deck Pavement".

[0045] Test results: For Example 1: 1) The ultra-thin colored paving material used for steel structure pedestrian bridge decks has a permeability coefficient of 0 at each measuring point, providing excellent anti-seepage performance. 2) The average pendulum friction coefficient of the ultra-thin colored paving material used for steel structure pedestrian bridge decks is 73BPN, which meets the high anti-skid pavement requirement of 70BPN; 3) The color retention performance of the ultra-thin colored paving material layer used in steel structure pedestrian bridge decks is improved by 30% compared to the uncovered layer; 4) The bonding performance of the ultra-thin colored paving material for steel structure pedestrian bridge decks: the bonding strength between epoxy zinc-rich primer and steel plate is 7 MPa, the bonding strength between methyl methacrylate primer and steel plate is 6 MPa, the bonding strength between anti-slip and wear-resistant layer and base layer is 5.5 MPa, and the bonding strength between the two anti-slip and wear-resistant layers is 6 MPa.

[0046] For Example 2: The permeability coefficient of the ultra-thin colored paving material thin layer used for steel structure pedestrian bridge deck is 0 at each measuring point, which can provide excellent seepage prevention performance. The pendulum friction coefficient is 81BPN, and the interlayer bonding performance meets the specifications.

[0047] For Example 3: The permeability coefficient of the ultra-thin colored paving material thin layer used for steel structure pedestrian bridge deck is 0 at each measuring point, which can provide excellent seepage prevention performance. The pendulum friction coefficient is 75BPN, and the interlayer bonding performance meets the specification requirements.

[0048] Through testing, the ultra-thin colored paving material for steel structure pedestrian bridge decks provided in this embodiment of the invention also has the following characteristics: (1) Coating appearance: After drying and molding, the color and aggregate particle distribution should be uniform, without cracks or aggregate particle falling off.

[0049] (2) Water resistance: No abnormal phenomena were observed after soaking in water for 24 hours.

[0050] (3) Alkali resistance: No abnormalities were observed after soaking in a saturated calcium hydroxide solution for 24 hours.

[0051] (4) Low temperature crack resistance of coating: After keeping it at -10℃ for 4 hours and placing it at room temperature for 4 hours as one cycle, no cracks were found after three consecutive cycles.

[0052] (5) Anti-slip property (BPN): BPN≥70, which is a high anti-slip type.

[0053] (6) The state of the base material in the container: no clumping or skin formation, easy to stir evenly.

[0054] (7) Adhesion of base material (circle test): Level 2 (According to JT / T712-2008 Road Anti-skid Coating, ≤ Level 4 is considered qualified).

[0055] (8) The aggregate particle size (mm), Mohs hardness, and artificially accelerated weather resistance all meet the standards required by JT / T712-2008 "Road Anti-skid Coating".

[0056] (9) No harmful substances such as benzene, toluene and xylene, benzene solvents, lead, cadmium, chromium and mercury were detected, and the VOC content was less than 10 times the standard of HJ457-2009.

[0057] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above description is only a specific embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. An ultra-thin colored paving material for steel structure pedestrian bridge decks, characterized in that, The paving material is integrally formed and includes, from top to bottom, a topcoat layer, an anti-slip and wear-resistant layer, and a base coat layer. The anti-slip and wear-resistant layer is made of modified water-based epoxy resin mortar. The modified waterborne epoxy resin mortar is composed of aggregates and binders; The binder comprises two components, A and B. Component A is a mixture of acrylic resin hybrid waterborne epoxy resin and color paste, and component B is composed of aliphatic polyamine and nanofiller. The mass ratio of component A to component B is 2:1 to 3.5:

1. The nanofiller accounts for 5% to 8% of the mass percentage of component B, the acrylic resin accounts for 10% to 15% of the mass percentage of component A, the weight ratio of the waterborne epoxy resin to the aggregate is 1:2.5 to 1:3, the color paste is a waterborne inorganic color paste, the coloring rate of the color paste is greater than 98%, and the color paste accounts for 1% to 5% of the mass percentage of component A. The base coating is made of methyl methacrylate primer or epoxy zinc-rich primer; The topcoat is a mixture of methacrylic resin and nano-anti-aging agent, wherein the nano-anti-aging agent accounts for 1% to 3% of the total weight of the topcoat. The methyl methacrylate primer comprises methyl methacrylate and pure water, and the epoxy zinc-rich primer comprises epoxy resin, zinc powder and curing agent. The zinc powder accounts for 60% to 65% of the mass of the primer coating, and the mass ratio of epoxy resin to curing agent is 10:

1.

2. The ultra-thin colored paving material for steel structure pedestrian bridge decks according to claim 1, characterized in that, The binder accounts for 10-20% of the mass of the aggregate, and the aggregate is a colored aggregate formed by sintering rock particles and pigments. The rock particles are one or more combinations of basalt, limestone, granite, and quartzite.

3. The ultra-thin colored paving material for steel structure pedestrian bridge decks according to claim 2, characterized in that, The aggregate has a particle size of 0.075 mm to 1.18 mm, wherein the aggregate with a particle size of 0.075 mm to 0.15 mm accounts for 20% to 30% of the total aggregate mass, the aggregate has a soundness of ≤12%, and a sand equivalent of ≥60%.

4. The ultra-thin colored paving material for steel structure pedestrian bridge decks according to claim 1, characterized in that, The total thickness of the anti-slip and wear-resistant layer is 4~6mm, and the anti-slip and wear-resistant layer is formed by stacking at least two layers. The thickness of the base layer is 50μm~150μm.

5. The method for preparing an ultra-thin colored paving material for a steel structure pedestrian bridge surface according to claim 4, characterized in that, Includes the following steps: S1: The steel bridge deck is rust-removed, ground and shot-blasted. The cleanliness after treatment reaches Sa2.5 level and the roughness reaches 50μm~100μm. Then, methyl methacrylate primer or epoxy zinc-rich primer is sprayed on the treated steel bridge deck. After surface drying and hardening, the base coating is obtained. S2: Modified water-based epoxy resin mortar is first applied to the surface of the base coating using the mortar method, and then applied by spraying or scraping. After curing, an anti-slip and wear-resistant layer is obtained by bonding to the base coating. S3: Apply a mixture of methacrylic resin and nano anti-aging agent to cover the anti-slip and wear-resistant layer, and obtain a topcoat layer after surface drying.

6. The method for preparing an ultrathin colored paving material for a steel structure pedestrian bridge surface according to claim 5, characterized in that, The spraying rate per unit area in S1 is 0.4 kg / m². 2 ~0.5kg / m 2 The surface drying time is ≤30 minutes, the surface drying temperature is 20℃~30℃, and the water absorption rate is ≤0.3%; the construction time in S2 is greater than 0.5 hours, until the adhesion strength of the obtained anti-slip and wear-resistant layer to the base layer is ≥5 MPa after curing; the amount of topcoat material used in S3 is 0.15 kg / m². 2 ~0.25kg / m 2 .

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