Epoxy Adhesives, Preparation Methods, and UHPC-SMA Bridge Deck Paving Method

Abstract

This application relates to an epoxy adhesive, its preparation method, and a UHPC-SMA bridge deck paving method. The adhesive comprises component A and component B in a mass ratio of 1:0.8–1.0. Component A, by mass parts, includes: 80–100 parts of bisphenol A type epoxy resin, 10–20 parts of bisphenol F type epoxy resin, 5–15 parts of reactive diluent, 5–15 parts of toughening agent, and 1–3 parts of silane coupling agent. Component B, by mass parts, includes: 50–70 parts of room temperature curing agent, 20–30 parts of high temperature curing agent, 0–10 parts of curing accelerator, and 1–3 parts of anti-settling agent. This epoxy adhesive possesses advantages such as good mechanical properties and strong adhesion, and its curing process and performance development are matched with the construction process.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of steel bridge deck pavement, in particular to an epoxy adhesive, a preparation method and a UHPC-SMA bridge deck pavement method. BACKGROUND

[0002] Ultra-high performance concrete (UHPC) is widely used in the field of steel bridge deck pavement due to its high material strength, large rigidity, good toughness and excellent durability. In particular, the UHPC / SMA rigid-flexible combined bridge deck pavement system can not only improve the rigidity of the steel bridge deck through the rigid structure layer to solve the problem of fatigue cracking of the bridge deck, but also can meet the driving comfort through the asphalt flexible wearing layer, and becomes a new and widely used steel bridge deck pavement structure system.

[0003] However, the interfacial adhesion between the UHPC structure layer and the SMA asphalt wearing layer during use is a big problem, which often causes diseases such as pavement structure layer peeling and slipping, and the reasons are as follows: firstly, the most unfavorable position under the action of vehicle and temperature loads is the UHPC / SMA interface, and the interlayer stress is large; secondly, the adhesion between the inorganic hydraulic material of UHPC and the high polymer material of SMA asphalt is poor due to the special adhesion base layer, harsh application environment and complex influencing factors.

[0004] For the UHPC / SMA pavement system, the specific pavement material, the specific construction process and the specific application scenario put forward new requirements for the bonding material: high tensile strength, small brittleness, large toughness, good synergistic deformation ability; strong adhesion, good adhesion with UHPC and SMA asphalt; initial viscosity, operable time, surface dry time and the like should match the construction, maintenance and other site processes; high-temperature melting and low-temperature solidification to ensure the cementation of the epoxy adhesive and SMA during 165℃ asphalt rolling and paving, and the like.

[0005] Therefore, it is necessary to develop a corresponding bonding material for the UHPC / SMA pavement structure. SUMMARY

[0006] The embodiment of the present application provides an epoxy adhesive, a preparation method and a UHPC-SMA bridge deck pavement method, which has the advantages of good mechanical properties and strong adhesion, and the gel solidification process and performance development are matched with the construction process.

[0007] In a first aspect, an epoxy adhesive is provided, which comprises A component and B component with a mass ratio of 1:0.8-1.0;

[0008] According to mass fraction, the A component comprises: bisphenol A type epoxy resin 80-100 parts, bisphenol F type epoxy resin 10-20 parts, active diluent 5-15 parts, toughening agent 5-15 parts, and silane coupling agent 1-3 parts.

[0009] The B component comprises, in terms of mass parts, 50-70 parts of room temperature curing agent, 20-30 parts of high temperature curing agent, 0-10 parts of curing accelerator, and 1-3 parts of anti-settling agent.

[0010] In some embodiments, the bisphenol A type epoxy resin has an epoxy equivalent weight of 180-192 and a viscosity of 6500-16000 mPa·s.

[0011] And / or, the bisphenol A type epoxy resin comprises one or more of NPEL127 and NPEL128.

[0012] And / or, the bisphenol F type epoxy resin has an epoxy equivalent weight of 160-180 and a viscosity of 2000-5000 mPa·s.

[0013] And / or, the bisphenol F type epoxy resin comprises one or more of NPEF-170, HS-170, and EPIKOTE 862.

[0014] And / or, the active diluent comprises one or more of butyl glycidyl ether, octyl glycidyl ether, 1,4-butanediol diglycidyl ether, and C12-C14 alkyl glycidyl ether.

[0015] And / or, the toughening agent has an epoxy equivalent weight of 0.15-0.25 and a viscosity of no more than 3500 mPa·s.

[0016] And / or, the toughening agent comprises one or more of toughening agent QS-BC and QS-BE.

[0017] And / or, the silane coupling agent comprises one or more of silane coupling agent KH-550, silane coupling agent KH-560, and silane coupling agent KH-570.

[0018] And / or, the high temperature curing agent has a melting point temperature of 160-180℃ and a curing temperature of 140-165℃.

[0019] And / or, the high temperature curing agent comprises one or more of succinic acid dihydrazide and adipic acid dihydrazide.

[0020] And / or, the curing accelerator comprises one of 2,4,6-tris(dimethylaminomethyl)phenol DMP-30, aminoethylpiperazine tertiary amine compound, and boron trifluoride complex.

[0021] And / or, the anti-settling agent comprises one or more of hydrophilic fumed silica, hydrophobic fumed silica, and organic bentonite.

[0022] In some embodiments, the room temperature curing agent comprises a flexible modified amine curing agent.

[0023] In some embodiments, the room-temperature curing agent further includes modified aliphatic amine curing agents and modified aromatic amine curing agents.

[0024] In some embodiments, the mass ratio of modified aliphatic amine curing agent, modified aromatic amine curing agent and flexible modified amine curing agent is 100:(10-30):(50-70).

[0025] In some embodiments, the modified aliphatic amine curing agent is derived by grafting a monoepoxide compound with one of ethylenediamine, triethylenetetramine, or diethylenetriamine.

[0026] And / or, the modified aromatic amine curing agent is a m-phenylenediamine aromatic amine or a 4,4'-diaminodiphenyl aromatic amine modified by a hydroxyl compound and an aryl carboxylic acid compound;

[0027] And / or, the flexible modified amine curing agent is a type of low molecular weight polyamide or polyether amine.

[0028] Secondly, a method for preparing the epoxy adhesive as described in any of the above-mentioned methods is provided, comprising the following steps:

[0029] Preparation of component A: Bisphenol A type epoxy resin and bisphenol F type epoxy resin are preheated at the first temperature for the first time, poured into a vacuum mixing tank, stirred at the first temperature, and then added with reactive diluent, toughening agent and silane coupling agent and stirred to obtain component A;

[0030] Preparation of component B: The room temperature curing agent and the high temperature curing agent are preheated at the second temperature for a second time. After adding the curing accelerator, the mixture is poured into a vacuum mixing tank and stirred at the second temperature. Then, the anti-settling agent is added and stirred at the second temperature to obtain component B.

[0031] Mix components A and B thoroughly to obtain an epoxy adhesive.

[0032] In some embodiments, the first temperature is 50–60°C, and the first time is 30 min;

[0033] And / or, at a second temperature of 50–60°C, for a second time of 30 min;

[0034] And / or, the stirring speed is 100-200 r / min.

[0035] Thirdly, a method for paving a UHPC-SMA bridge deck is provided, which includes the following steps:

[0036] Provide any of the epoxy adhesives described above;

[0037] Epoxy adhesive is applied to the coating interface of the UHPC substrate and cured to allow the epoxy adhesive on the coating interface to fully dry.

[0038] SMA asphalt mixture is laid and compacted on a dry epoxy adhesive.

[0039] In some embodiments, the method further includes: treating the UHPC substrate surface with an automatic shot blasting machine to remove oil, water stains and dust, and to make the UHPC substrate surface roughness 0.45 to 0.55 mm;

[0040] And / or, the coating weight of the epoxy adhesive is 0.8 kg / m². 2 ~1.0kg / m 2 ;

[0041] And / or, the curing time shall not be less than the actual drying time of the epoxy adhesive;

[0042] And / or, the temperature of the SMA asphalt mixture during paving shall not be lower than 160°C.

[0043] The beneficial effects of the technical solution provided in this application include:

[0044] To address the construction requirements of the tack coat in UHPC / SMA paving structures, a component A with low viscosity, high epoxy value, and good workability was prepared using bisphenol A epoxy resin and bisphenol F type epoxy resin interpenetrating network technology. This component exhibits no low-temperature crystallization and has excellent workability.

[0045] Meanwhile, the room-temperature curing agent in component B is an internal toughening agent, while the toughening agent in component A is an external toughening agent. The synergistic toughening effect of the internal and external toughening agents greatly improves the toughness of the colloid while ensuring the strength of the cured product.

[0046] Utilizing the high melting point and high-temperature curing characteristics of high-temperature curing agents, the mixture melts and then cures at a high temperature of 165℃. In its molten state, it can better bond with asphalt mixtures, further solidify the colloid, and further enhance the cohesion of the colloid.

[0047] To achieve synergistic internal and external toughening with the toughening agent in component A, the room-temperature curing agent provided in this application includes a flexible modified amine curing agent. Specifically, the flexible modified amine curing agent is a type of low molecular weight polyamide or polyether amine. The flexible modified amine curing agent employs flexible grafting technology and is classified as an internal toughening agent, while the Kiesl toughening agent uses an island-structure toughening system and is classified as an external toughening agent. The synergistic toughening by the internal and external toughening agents significantly improves the toughness of the colloid while ensuring the strength of the cured product.

[0048] Furthermore, in order to adjust the curing speed, the room-temperature curing agent provided in this application also includes modified aliphatic amine curing agents and modified aromatic amine curing agents. The use of a blending and compounding technology of low-viscosity, high-activity modified aliphatic amines and low-viscosity, slow-curing modified aromatic amine curing agents allows for adjustment of the curing speed, suitable construction time, rapid early strength development, and prevents asphalt from sticking to wheels during paving, while maintaining high strength and sufficient toughness without damage under construction vehicle loads. Attached Figure Description

[0049] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0050] Figure 1 This is a flowchart illustrating the epoxy adhesive preparation method provided in an embodiment of this application. Detailed Implementation

[0051] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0052] This application provides an epoxy adhesive comprising component A and component B in a mass ratio of 1:0.8 to 1.0;

[0053] The A component, by mass fraction, comprises: 80-100 parts of bisphenol A epoxy resin, 10-20 parts of bisphenol F epoxy resin, 5-15 parts of reactive diluent, 5-15 parts of toughening agent, and 1-3 parts of silane coupling agent.

[0054] Based on the mass fractions, component B comprises: 50-70 parts of room temperature curing agent, 20-30 parts of high temperature curing agent, 0-10 parts of curing accelerator, and 1-3 parts of anti-settling agent.

[0055] To address the construction requirements of the tack coat in UHPC / SMA paving structures, a component A with low viscosity, high epoxy value, and good workability was prepared using bisphenol A epoxy resin and bisphenol F type epoxy resin interpenetrating network technology. This component exhibits no low-temperature crystallization and has excellent workability.

[0056] Meanwhile, the room-temperature curing agent in component B is an internal toughening agent, while the toughening agent in component A is an external toughening agent. The synergistic toughening effect of the internal and external toughening agents greatly improves the toughness of the colloid while ensuring the strength of the cured product.

[0057] Utilizing the high melting point and high-temperature curing characteristics of high-temperature curing agents, the mixture melts and then cures at a high temperature of 165℃. In its molten state, it can better bond with asphalt mixtures, further solidify the colloid, and further enhance the cohesion of the colloid.

[0058] The bisphenol A type epoxy resin has an epoxy equivalent of 180-192 and a viscosity of 6500-16000 mPa·s; preferably, the bisphenol A type epoxy resin is a mixture of NPEL127 and NPEL128 in a mass ratio of (3-5):1.

[0059] The bisphenol F type epoxy resin has an epoxy equivalent of 160-180 and a viscosity of 2000-5000 mPa·s; preferably, the bisphenol F type epoxy resin is one or more of NPEF-170, HS-170 and EPIKOTE 862.

[0060] The active diluent includes one or more of butyl glycidyl ether, octyl glycidyl ether, 1,4-butanediol diglycidyl ether, and C12-C14 alkyl glycidyl ether.

[0061] The toughening agent has an epoxy equivalent value of 0.15–0.25 and a viscosity not exceeding 3500 mPa·s. Preferably, the toughening agent includes one or more of toughening agents QS-BC and QS-BE. Qishi toughening agent adopts an island-structure toughening system, belonging to external toughening agents, and can synergistically toughen with the internal toughening agent in component B. It greatly improves the toughness of the colloid while ensuring the strength of the cured product.

[0062] The silane coupling agent includes one or more of silane coupling agents KH-550, KH-560, and KH-570.

[0063] The high-temperature curing agent has a melting point of 160–180°C and a curing temperature of 140–165°C.

[0064] The high-temperature curing agent includes one or more of succinic dihydrazide and adipate dihydrazide.

[0065] The curing accelerator includes one of 2,4,6-tris(dimethylaminomethyl)phenol DMP-30, aminoethylpiperazine tertiary amine compounds, and boron trifluoride complexes.

[0066] The anti-settling agent includes one or more of hydrophilic silica, hydrophobic silica, and organobentonite.

[0067] To achieve synergistic internal and external toughening with the toughening agent in component A, the room-temperature curing agent provided in this application includes a flexible modified amine curing agent. Specifically, the flexible modified amine curing agent is a type of low molecular weight polyamide or polyether amine. The flexible modified amine curing agent employs flexible grafting technology and is classified as an internal toughening agent, while the Kiesl toughening agent uses an island-structure toughening system and is classified as an external toughening agent. The synergistic toughening by the internal and external toughening agents significantly improves the toughness of the colloid while ensuring the strength of the cured product.

[0068] Low molecular weight polyamides have a number average molecular weight range of 500 to 2000.

[0069] Polyamides are a class of substances formed by the condensation of dimerized vegetable oil fatty acids or esters with aliphatic amines. The vegetable oils and fatty acids are mostly linoleic acid and tung oil acid, and the aliphatic amines used are mostly diethylenetriamine and triethylenetetramine. Polyether amines are obtained by amination of polyethylene glycol, polypropylene glycol, or ethylene glycol / propylene glycol copolymers under high temperature and pressure.

[0070] Furthermore, in order to adjust the curing speed, the room-temperature curing agent provided in this application also includes modified aliphatic amine curing agents and modified aromatic amine curing agents. The use of a blending and compounding technology of low-viscosity, high-activity modified aliphatic amines and low-viscosity, slow-curing modified aromatic amine curing agents allows for adjustment of the curing speed, suitable construction time, rapid early strength development, and prevents asphalt from sticking to wheels during paving, while maintaining high strength and sufficient toughness without damage under construction vehicle loads.

[0071] When blending and compounding, the mass ratio of modified aliphatic amine curing agent, modified aromatic amine curing agent and flexible modified amine curing agent is 100:(10~30):(50~70).

[0072] The modified aliphatic amine curing agent is obtained by grafting a monoepoxide compound with one of ethylenediamine, triethylenetetramine, or diethylenetriamine; wherein, there are a variety of alternative monoepoxide compounds, for example, the monoepoxide compound can be selected from ethylene oxide, epichlorohydrin, or epichlorohydrin.

[0073] The modified aromatic amine curing agent is a m-phenylenediamine or 4,4'-diaminodiphenyl aromatic amine modified with a hydroxyl compound and an aryl carboxylic acid compound. A variety of materials can be selected for the hydroxyl compound and the aryl carboxylic acid compound; for example, the hydroxyl compound can be selected from polypropylene glycol, octanol, or styrene-modified phenol; the aryl carboxylic acid compound can be selected from benzoic acid or salicylic acid.

[0074] See Figure 1 As shown, this application also provides a method for preparing the epoxy adhesive as described above, which includes the following steps:

[0075] 101. Preparation of Component A: Preheat bisphenol A epoxy resin and bisphenol F epoxy resin to the first temperature for the first time, pour them into a vacuum mixing tank, stir at the first temperature for 10-15 minutes, then add reactive diluent, toughening agent and silane coupling agent and stir for 10-15 minutes to obtain Component A.

[0076] The first temperature is 50-60℃, the first time is 30min, and the stirring speed is 100-200r / min.

[0077] 102. Preparation of component B: Preheat the room temperature curing agent and the high temperature curing agent at the second temperature for a second time, add the curing accelerator and pour into a vacuum mixing tank, stir at the second temperature for 10-15 minutes, then add the anti-settling agent and stir at the second temperature for 30-40 minutes to obtain component B.

[0078] The second temperature is 50-60℃, the second time is 30 min, and the stirring speed is 100-200 r / min.

[0079] 103. Mix components A and B evenly to obtain epoxy adhesive.

[0080] There is no strict order between step 101, which prepares component A, and step 102, which prepares component B. They can be performed simultaneously or one after the other.

[0081] This application also provides a UHPC-SMA bridge deck paving method, which includes the following steps:

[0082] 201: Provides the epoxy adhesive of the above embodiments.

[0083] 202: Apply epoxy adhesive to the coating interface of the UHPC substrate and cure it to allow the epoxy adhesive on the coating interface to dry completely.

[0084] The coating amount of epoxy adhesive is 0.8 kg / m². 2 ~1.0kg / m 2 The curing time should not be less than the actual drying time of the epoxy adhesive.

[0085] Before coating, the method further includes treating the UHPC substrate surface with an automatic shot blasting machine to remove oil, water stains and dust, and to make the UHPC substrate surface roughness 0.45 to 0.55 mm.

[0086] 203: SMA asphalt mixture paving construction is carried out on the dry epoxy adhesive, and compacted. The temperature of SMA asphalt mixture during paving shall not be lower than 160℃.

[0087] The present application will be described in detail below through examples and comparative examples.

[0088] Example 1

[0089] Preparation of Component A: 80 parts of bisphenol A type epoxy resin (60 parts of NPEL127 and 20 parts of NPEL128) and 20 parts of bisphenol F type epoxy resin were preheated in an oven at 50°C for 30 minutes, poured into a vacuum mixing tank and heated to 50°C for 15 minutes at a stirring speed of 200 r / min. Then, 10 parts of reactive diluent (XY622, i.e., 1,4-butanediol diglycidyl ether), 5 parts of toughening agent (QS-BE), and 1 part of silane coupling agent (KH560) were added and stirred for 15 minutes to form a mixture to obtain Component A.

[0090] Preparation of component B: 50 parts of room temperature curing agent (100 parts of KC19, 30 parts of KC26, and 70 parts of 650 polyamide curing agent, KC19 and KC26 being low-viscosity, high-activity modified aliphatic amine curing agent and low-viscosity, slow-curing modified aromatic amine curing agent, respectively, provided by Wuhan Kecong New Materials Co., Ltd.) and 30 parts of high-temperature curing agent were preheated in an oven at 50°C for 30 minutes. 5 parts of DMP-30 were added and poured into a vacuum mixing tank, heated to 50°C and stirred for 15 minutes. Then, 3 parts of hydrophobic fumed silica were added and stirred at 50°C for 30 minutes to obtain curing agent component B.

[0091] When using, mix component A and component B in a mass ratio of 1:0.8 at room temperature to obtain the epoxy adhesive.

[0092] Example 2

[0093] Preparation of Component A: 80 parts of bisphenol A type epoxy resin (60 parts of NPEL127 and 20 parts of NPEL128) and 20 parts of bisphenol F type epoxy resin were preheated in an oven at 50°C for 30 minutes, poured into a vacuum mixing tank and heated to 50°C for 15 minutes at a stirring speed of 200 r / min. Then, 10 parts of reactive diluent (XY622), 5 parts of toughening agent (QS-BE), and 1 part of silane coupling agent (KH560) were added and stirred for 15 minutes to form a mixture to obtain Component A.

[0094] Preparation of component B: 50 parts of room temperature curing agent (100 parts of KC19, 30 parts of KC26, 50 parts of 650 polyamide curing agent) and 30 parts of high temperature curing agent were preheated in an oven at 50°C for 30 minutes. 5 parts of DMP-30 were added and poured into a vacuum mixing tank and heated to 50°C and stirred for 15 minutes. Then, 3 parts of hydrophobic fumed silica were added and stirred at 50°C for 30 minutes to obtain curing agent component B.

[0095] When using, mix component A and component B in a mass ratio of 1:0.8 at room temperature to obtain the epoxy adhesive.

[0096] Example 3

[0097] Preparation of Component A: 80 parts of bisphenol A type epoxy resin (60 parts of NPEL127 and 20 parts of NPEL128) and 20 parts of bisphenol F type epoxy resin were preheated in an oven at 50°C for 30 minutes, poured into a vacuum mixing tank and heated to 50°C for 15 minutes at a stirring speed of 200 r / min. Then, 10 parts of reactive diluent (XY622), 5 parts of toughening agent (QS-BE), and 1 part of silane coupling agent (KH560) were added and stirred for 10 minutes to form a mixture to obtain Component A.

[0098] Preparation of component B: 50 parts of room temperature curing agent (100 parts of KC19, 10 parts of KC26, 70 parts of 650 polyamide curing agent) and 30 parts of high temperature curing agent were preheated in an oven at 50°C for 30 minutes. 5 parts of DMP-30 were added and poured into a vacuum mixing tank and heated to 50°C and stirred for 15 minutes. Then, 3 parts of hydrophobic fumed silica (HB-139) were added and stirred at 50°C for 30 minutes to obtain curing agent component B.

[0099] When using, mix component A and component B in a mass ratio of 1:0.8 at room temperature to obtain the epoxy adhesive.

[0100] Comparative Example 1

[0101] The epoxy adhesive provided in Comparative Example 1 differs from that in Example 1 in that:

[0102] The mass fraction of the low-viscosity, slow-curing modified aromatic amine curing agent KC26 in component B is 0.

[0103] Comparative Example 2

[0104] The epoxy adhesive provided in Comparative Example 2 differs from that in Example 1 in that:

[0105] The mass fraction of low molecular weight polyamide curing agent 650 added in component B is 0.

[0106] Comparative Example 3

[0107] The epoxy adhesive provided in Comparative Example 3 differs from that in Example 1 in that:

[0108] The amount of high-temperature curing agent added in component B is 0.

[0109] Comparative Example 4

[0110] The epoxy adhesive provided in Comparative Example 4 is KD-HYP epoxy adhesive oil imported from Japan.

[0111] Material performance testing:

[0112] The epoxy adhesives prepared in Examples 1-3 and Comparative Examples 1-4 were subjected to the following performance tests:

[0113] (1) Workable time, surface drying time, and complete drying time: The workable time was tested according to GB / T 7123.1-2015 "Determination of workable time of multi-component adhesives", and the surface drying time and complete drying time of the adhesive were tested according to GB / T16677-2008 "Test methods for waterproof coatings for buildings". The results are shown in Table 1.

[0114] Table 1: Working Time and Surface Drying Time of Epoxy Adhesives

[0115]

[0116] As shown in Table 1, the workable times for Implementations 1-3 are 50, 45, and 35 minutes respectively, meeting the requirement of ≥30 minutes in JTG / T3364-02-2019. However, the workable time for Comparative Example 1 is only 20 minutes, which is too short and unfavorable for on-site construction. The results indicate that adjusting the ratio of low-viscosity, high-activity modified aliphatic amine and low-viscosity, slow-curing modified aromatic amine curing agent can significantly improve the workable time of the adhesive. Furthermore, by determining an appropriate mixing ratio, while meeting the workable time requirement, the surface drying time and actual drying time can be shortened as much as possible, allowing for rapid early strength development and facilitating construction progress.

[0117] (2) Tensile properties: The tensile strength and elongation at break of the adhesive were tested according to GB / T 2567-2021 "Test Methods for Properties of Resin Castings". The epoxy adhesives prepared in Examples 1-3 and Comparative Examples 1-4 were cast into molds and pre-cured at 25°C for 24 hours. The cured material was then placed in an oven at 150°C for 1 hour, cooled to room temperature, and completely cured before demolding. The results are shown in Table 2.

[0118] Table 2: Tensile Properties of Epoxy Adhesives

[0119]

[0120] As shown in Table 2, the tensile strengths of Examples 1-3 are 3.90, 4.65, and 4.14 MPa, respectively, and the elongation at break is 252%, 195%, and 236%, respectively, which meets the requirements of ≥3.0 MPa and 100% (design requirement 190%) in JTG / T3364-02-2019. However, tensile strength and elongation at break are negatively correlated; increasing strength requires sacrificing toughness. Comparative Example 2 exhibits a high strength of 5.52 MPa, but it is brittle, with an elongation at break of only 62%, lower than 190%, and even lower than the standard requirement of 100%. The results indicate that the flexible modified amine curing agent, using flexible grafting technology and combined with an island-structure toughening system, achieves synergistic toughening of the internal and external toughening agents. This significantly improves the toughness of the colloid while ensuring the strength of the cured material, giving it the ability to deform synergistically and meeting the requirements for bridge deck pavement.

[0121] (3) Performance testing of UHPC / SMA composite components: When using the epoxy adhesives from Examples 1-3 and Comparative Examples 1-4 as the adhesive layer, 300×300×50mm UHPC boards were prepared. The UHPC compressive strength was ≥140MPa, flexural strength was ≥25MPa, and elastic modulus was ≥42.5GPa. Steam curing was performed for 3 days, followed by surface treatment using an automatic shot blasting machine. The texture depth was tested using the sand-laying method, with a thickness of 0.50mm. Epoxy adhesive was applied to the UHPC interface at a rate of 0.8kg / m², and cured at room temperature for at least 24 hours. After the surface was fully dry, 30mm of SMA-10 asphalt mixture was compacted and laid (paving temperature was 165℃). After cooling, the mixture was cut into 90×90mm test specimens and cured for 3-4 days. Oblique shear and pull-out tests were conducted according to JTG / T3364-02-2019. The specific test results are shown in Table 3.

[0122] Table 3: Bonding properties of composite components

[0123]

[0124] According to the data in Table 3, the shear strengths of composite components 1-3 are 3.32, 3.15, and 3.18 MPa, respectively, meeting the design requirement of ≥1.8 MPa; the pull-out strengths are 3.52, 3.38, and 3.35 MPa, meeting the current requirement of ≥1.6 MPa. Comparative Example 2 composite component has a shear strength of only 0.85 MPa and a pull-out strength of only 1.02 MPa, indicating cohesive failure due to the adhesive. This is because Comparative Example 2 is brittle and lacks toughness, leading to failure during asphalt paving. Comparative Example 3 composite component has a shear strength of 1.25 MPa and a pull-out strength of 1.56 MPa, indicating interface failure between the adhesive and SMA. This is because, without a high-temperature curing agent, the colloid mechanism is similar to that of epoxy resin type I, failing to melt at high temperatures after curing, resulting in poor adhesion between the asphalt mixture and the colloid. Therefore, in terms of results, the synergistic toughening technology of internal and external toughening agents and the second-stage curing characteristics of high-temperature curing agents have performance development that is compatible with the UHPC / SMA paving process. As an adhesive layer, it has good interlayer bonding effect and improves the overall integrity of the paving structure.

[0125] In summary, the epoxy adhesive for UHPC / SMA pavement structures provided in this application has good mechanical properties and strong adhesion. The curing process and performance development of the adhesive are matched with the construction process. It can melt at high temperature and re-cur at low temperature. The adhesive itself has good stability and strong adhesion to the pavement structure, which improves the overall service life of the pavement structure.

[0126] In the description of this application, it should be noted that the terms "upper," "lower," etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application. Unless otherwise expressly specified and limited, the terms "installed," "connected," and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication between two elements. For those skilled in the art, the specific meaning of the above terms in this application can be understood according to the specific circumstances.

[0127] It should be noted that in this application, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0128] The above description is merely a specific embodiment of this application, enabling those skilled in the art to understand or implement this application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features claimed herein.

Claims

1. An epoxy adhesive, characterized by, It includes A component and B component with mass ratio of 1:0.8-1.0; According to mass fraction, the A component includes: bisphenol A type epoxy resin 80-100 parts, bisphenol F type epoxy resin 10-20 parts, active diluent 5-15 parts, toughening agent 5-15 parts, silane coupling agent 1-3 parts; According to mass fraction, the B component includes: room temperature curing agent 50-70 parts, high temperature curing agent 20-30 parts, curing accelerator 0-10 parts, anti-settling agent 1-3 parts; The room temperature curing agent includes flexible modified amine curing agent, modified aliphatic amine curing agent and modified aromatic amine curing agent, and the mass ratio of modified aliphatic amine curing agent, modified aromatic amine curing agent and flexible modified amine curing agent is 100: (10-30): (50-70), and the high temperature curing agent includes one or more of succinic acid dihydrazide and adipic acid dihydrazide; The flexible modified amine curing agent is a low molecular weight polyamide, and the number average molecular weight ranges from 500 to 2000; The modified aliphatic amine curing agent is grafted and modified from one of a single epoxy compound, ethylenediamine, triethylenetetramine or diethylenetriamine; wherein the single epoxy compound is selected from ethylene oxide, propylene oxide and epichlorohydrin; The modified aromatic amine curing agent is modified from m-phenylenediamine aromatic amine or 4,4'-diaminodiphenyl aromatic amine by using a hydroxyl compound and an aryl carboxylic acid compound; the hydroxyl compound is selected from polypropylene glycol, octanol or styrenated phenol; and the aryl carboxylic acid compound is selected from benzoic acid or salicylic acid; The toughening agent has an epoxy equivalent value of 0.15-0.25 and a viscosity of not more than 3500 mPa·s; The toughening agent includes one or more of toughening agents QS-BC and QS-BE.

2. The epoxy adhesive according to claim 1, wherein: The bisphenol A type epoxy resin has an epoxy equivalent value of 180-192 and a viscosity of 6500-16000 mPa·s; And / or, the bisphenol A type epoxy resin includes one or more of NPEL127 and NPEL128; And / or, the bisphenol F type epoxy resin has an epoxy equivalent value of 160-180 and a viscosity of 2000-5000 mPa·s; And / or, the bisphenol F type epoxy resin includes one or more of NPEF-170, HS-170 and EPIKOTE 862; And / or, the active diluent includes one or more of butyl glycidyl ether, octyl glycidyl ether, 1,4-butanediol diglycidyl ether and C12-C14 alkyl glycidyl ether; And / or, the silane coupling agent includes one or more of silane coupling agent KH-550, silane coupling agent KH-560 and silane coupling agent KH-570; And / or, the curing accelerator includes one of 2,4,6-tris (dimethylaminomethyl) phenol DMP-30, aminoethylpiperazine tertiary amine compound and boron trifluoride complex; And / or, the anti-settling agent includes one or more of hydrophilic white carbon black, hydrophobic white carbon black and organic bentonite.

3. A method of preparing an epoxy adhesive as claimed in any one of claims 1 to 2, characterized in that, It includes the following steps: Preparation of A component: Bisphenol A type epoxy resin and bisphenol F type epoxy resin are preheated at a first temperature for a first time, poured into a vacuum stirring tank, stirred at the first temperature, then active diluent, toughening agent and silane coupling agent are added and stirred to obtain A component; Preparation of B component: room temperature curing agent and high temperature curing agent are preheated at a second temperature for a second time, poured into a vacuum stirring tank after adding curing accelerator, stirred at the second temperature, then anti-sedimentation agent is added and stirred at the second temperature to obtain B component; Mixing A component and B component uniformly to obtain epoxy adhesive.

4. The preparation method of the epoxy adhesive according to claim 3, characterized in that: the first temperature is 50-60 DEG C and the first time is 30 min; and / or, the second temperature is 50-60 DEG C and the second time is 30 min; and / or, the stirring speed is 100-200 r / min.

5. A method of UHPC-SMA deck pavement, characterized in that, The method comprises the following steps: providing the epoxy adhesive according to any one of claims 1-2; applying the epoxy adhesive on the coating interface of the UHPC substrate and curing to dry the epoxy adhesive on the coating interface; carrying out SMA asphalt mixture paving construction on the dried epoxy adhesive and rolling into shape.

6. The UHPC-SMA bridge deck pavement method according to claim 5, characterized in that: the method further comprises: treating the surface of the UHPC substrate with an automatic shot blasting machine to remove oil stains, water stains and dust and make the surface roughness of the UHPC substrate 0.45-0.55 mm; and / or the epoxy adhesive is applied at a rate of 0.8 kg / m 2 ~ 1.0 kg / m 2 ; and / or, the curing time is not less than the drying time of the epoxy adhesive; and / or, the temperature of the SMA asphalt mixture during paving is not less than 160 DEG C.

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