Polymer elastic composite material for ballastless track system and preparation method thereof

Abstract

The invention discloses a macromolecular elastic composite material for a ballastless track system and a preparation method thereof, and relates to an elastic composite material and a preparation method thereof.The material comprises a component A, a component B and a component C. The component A comprises, by weight, 15-18 parts of epoxy resin and 15-18 parts of a polysulfide rubber component A; the component B is prepared from the following components in parts by weight: 33 to 38 parts of a polysulfide rubber component B, 15 to 18 parts of a thickening agent, 0.005 to 0.05 part of a tough material and 0.3 to 0.8 part of a reinforcing agent; and the component C comprises the following components in parts by weight: 1.2-1.8 parts of an accelerant, 1.5-1.8 parts of an active agent, 1.0-2.0 parts of a curing agent and 0.1-0.3 part of a defoaming agent. The method comprises the following steps: S1, preparing; s2, preparing the component A; s3, preparing a component B; s4, mixing; and S5, stirring. The rail fastener is easy and convenient to install, simple in construction technology and high in installation efficiency, the problem of rail fastener failure can be solved, and the rail traffic design requirement can be met.

Description

Technical Field

[0001] The present invention relates to an elastic composite material and a preparation method thereof, in particular to a polymer elastic composite material for a ballastless track system and a preparation method thereof. Background Art

[0002] Traditional ballastless tracks refer to track structures that use integral bases such as concrete and asphalt mixtures to replace granular ballast beds. The main types are as follows: CRTS I type double-block ballastless tracks, CRTS II type double-block ballastless tracks, CRTS I type slab ballastless tracks, CRTS II type slab ballastless tracks, and CRTS III type slab ballastless tracks. The main restraint methods for the above track structures are WJ-7 type, WJ-8 type, W300-1 type, and SFC type fasteners.

[0003] Traditional ballastless tracks use discrete supports such as fasteners and bolts to fix and restrain the rails. However, their installation is relatively cumbersome, the construction process is complex and the accuracy requirements are high, and the manual installation efficiency is low; during the normal service of the track, with the irregular vibration of the track, problems such as loosening, falling off, and fracture of the anchor bolts of the fasteners will occur, and even directly lead to the failure of related track fasteners. Therefore, frequent track adjustment and safety maintenance need to be carried out manually; in addition, during the normal operation of the train, due to the high-frequency and irregular impact loads and vibration loads of the train on the rails, strong aerodynamic noise will inevitably be generated, seriously affecting the surrounding environment.

[0004] At present, some polymer elastic composite materials for embedded continuous support ballastless track systems have emerged in track construction projects. By injecting the polymer elastic composite material into the rail support groove and wrapping it with the track, a wrapped structure is formed to replace the traditional fasteners, playing the role of continuous support and fixing the rails. According to the mechanical requirements of the embedded track structure, the polymer restraint material wrapping the track must be able to meet the transverse dynamic and static stiffness, vertical dynamic and static stiffness, longitudinal stiffness, vibration characteristics, noise control, high frequency, and high response required by the track design. However, the existing single or blended polymer materials are difficult to meet the above track design requirements at the same time, and there are still problems in construction technology, performance, and environmental protection.

[0005] The invention patent application with the publication number of CN103351579A discloses a polymer composite material for an embedded track system. The disadvantages of this patent are as follows: The filling materials are rubber powder, cork powder, expanded perlite, etc. The main function of the filler is to improve the toughness of the material and adjust the mechanical properties. In this invention patent application, the proportion of rubber powder is relatively large, but the rubber powder material is mainly made by grinding waste tires, and the uncertainty of the material is relatively large, and the mechanical properties are low, so that the material still cannot meet the operation requirements of high frequency and high response of urban rail transit structures. Summary of the Invention

[0006] The technical problem to be solved by the present invention is to provide a polymer elastic composite material for a ballastless track system and a preparation method thereof, so as to solve the technical problem that it is difficult for polymer materials in the prior art to simultaneously meet the requirements of track design.

[0007] The technical solution for solving the above technical problem is: A polymer elastic composite material for a ballastless track system, comprising component A, component B and component C,

[0008] Component A includes, by weight:

[0009] Epoxy resin, 15 - 18 parts,

[0010] Polysulfide rubber component A, 33 - 38 parts;

[0011] Component B includes, by weight:

[0012] Polysulfide rubber component B, 15 - 18 parts,

[0013] Thickening agent, 15 - 18 parts,

[0014] Toughness material, 0.005 - 0.05 parts,

[0015] Reinforcing agent, 0.3 - 0.8 parts;

[0016] Component C includes, by weight:

[0017] Accelerator, 1.2 - 1.8 parts,

[0018] Activator, 1.5 - 1.8 parts,

[0019] Curing agent, 1.0 - 2.0 parts,

[0020] Defoaming agent, 0.1 - 0.3 parts.

[0021] A further technical solution of the present invention is: The epoxy resin used is bisphenol A type epoxy resin (E-03 type).

[0022] A further technical solution of the present invention is: The polysulfide rubber component A uses a polysulfide prepolymer as the main agent and additive A is added. The weight ratio of the main agent to additive A is 3:1; Additive A is composed of one or more of dibutyl phthalate, chlorinated biphenyl, chlorinated paraffin, butyl benzyl phthalate, alkylbenzene compounds, sulfur-containing organic ammonia compounds, ethylenediamine compounds, diphenyl guanidine, tetramethyl thiuram disulfide, and benzothiazole disulfide in any ratio combination.

[0023] A further technical solution of the present invention is that the polythiol rubber component B uses a plasticizer as the main agent and additive B is added. The weight ratio of the main agent to additive B is 1.5:1; the additive B is composed of one or more of a condensate of dichloroethane and an alkali metal tetrasulfide, dichloroethane, a condensate of bis(2-chloroethyl) formal and an alkali metal disulfide, bis(dichloro vinyl) formal, and a condensate of trichloropropane and an alkali metal polysulfide, combined in any ratio.

[0024] A further technical solution of the present invention is that the thickener is composed of one or more of organosilane compounds, alkylphenolic resins, and nonionic associative thickeners, combined in any ratio.

[0025] A further technical solution of the present invention is that the toughening material is composed of one or more of hydrated aluminosilicate, natural zeolite, and rubber powder, combined in any ratio.

[0026] A further technical solution of the present invention is that the reinforcing agent is composed of one or more of precipitated silica, fumed silica, and ultrafine silica gel, combined in any ratio.

[0027] A further technical solution of the present invention is that the promoter is composed of one or more of vinyltris(β-methoxyethoxy)silane, γ-glycidoxypropyltrimethoxysilane, γ-aminopropyltriethoxysilane, and 3-(methacryloyloxy)propyltrimethoxysilane, combined in any ratio; the activator is composed of one or more of the epoxy resin halogen-free diluents SF-66, HK-66, HS-62, and S-7400, combined in any ratio.

[0028] A further technical solution of the present invention is that the curing agent is composed of one or more of dimethylamine, 2,4,6-tris(dimethylaminomethyl)phenol, 4-hydroxybenzoic acid, ethylenediamine, hexamethylenediamine, and diethylenetriamine, combined in any ratio; the defoaming agent is composed of one or more of modified polysiloxane and polyether-modified organosilicon, combined in any ratio.

[0029] Another technical solution of the present invention is a preparation method of a high molecular elastic composite material for a ballastless track system, including the following steps:

[0030] S1. Preparation: Measure the environmental temperature and humidity conditions, check the states of each component raw material. If low-temperature solidification occurs, preheat the epoxy resin to 25°C to 35°C and maintain it throughout the preparation and stirring process;

[0031] S2. Prepare component A: Sequentially put the epoxy resin and polythiol rubber A into the reaction device according to the dosage to prepare component A;

[0032] S3. Preparation of Component B: Put the polysulfide rubber Component B into the reaction device, then add the thickener in portions and observe the state of the material. If there is no precipitation or separation phenomenon, then add the reinforcing agent and the toughening material in sequence to make Component B.

[0033] S4. Mixing: Mix Component A and Component B, and then add the reagents in Component C to the mixture of Component A and Component B in sequence: accelerator → activator → curing agent → defoamer to make the mixture.

[0034] S5. Stirring: Use an electric stirrer to fully stir the prepared mixture. The no-load speed of the stirrer reaches more than 1000 r / min and stir continuously for 5 - 10 min. When the materials are completely mixed, and the color on the surface of the material liquid is uniform, there is no lumpy precipitation or coagulation and no stratification phenomenon, it is determined that the stirring is sufficient, that is, a fluid-like polymer elastic composite material for the ballastless track system is made.

[0035] Due to the above structure, compared with the prior art, the polymer elastic composite material for the ballastless track system of the present invention and its preparation method have the following beneficial effects:

[0036] 1. The polymer elastic composite material for the ballastless track system of the present invention, because it uses epoxy resin modified by polysulfide rubber and is combined with a reinforcing agent at the same time, effectively retains the characteristics of high structural strength and good mechanical properties of both, and can meet the requirements of the urban rail transit for lateral dynamic and static stiffness, vertical dynamic and static stiffness, longitudinal stiffness, vibration characteristics, noise control, high frequency, and high response.

[0037] In addition, due to the interaction between the thickener and the curing agent, the polymer elastic composite material for the ballastless track system of the present invention has the performance of rapid prototyping in 3 h, and can meet the requirements of the urban rail transit for a short outage period and rapid construction requirements.

[0038] 2. The polymer elastic composite material for the ballastless track system of the present invention is based on epoxy resin, and can preferably retain the characteristics of stable chemical properties, corrosion resistance, strong adhesion, and good insulation. Moreover, through modification, its ability to resist ultraviolet rays, corrosion, and high temperature can be improved.

[0039] 3. Due to the good effect of the activator, the polymer elastic composite material for the ballastless track system of the present invention has the ability of segmented construction and staggered pouring in the time boundary conditions of the material, and has good continuous bonding ability between new and old materials.

[0040] 4. The present invention forms a wrapped structure by injecting a polymer elastic composite material into the rail seat groove to wrap the track, replacing the traditional fasteners, and playing the role of continuously supporting and fixing the rail. It is easy to install, with a simple construction process and low precision requirements, and high installation efficiency. Moreover, during the operation of the track, problems such as fastener loosening, falling off, and anchor bolt fracture will not occur, greatly reducing manual track adjustment and safety maintenance.

[0041] Next, in combination with specific embodiments, the technical features of the polymer elastic composite material and its preparation method for the ballastless track system of the present invention will be further described. Specific Embodiments

[0042] Example 1:

[0043] A polymer elastic composite material for a ballastless track system, the ballastless track system being an embedded continuous support ballastless track system. The polymer elastic composite material includes component A, component B, and component C. Component A, component B, and component C respectively include the components shown in Table 1 by weight:

[0044] Table 1 - List of Components Included in Component A, Component B, and Component C in Example 1

[0045]

[0046] The preparation method of the polymer elastic composite material for the ballastless track system in this Example 1 includes the following steps:

[0047] S1. Preparation: Measure the environmental temperature and humidity conditions, check the states of each component raw material. If low-temperature solidification occurs, preheat the epoxy resin to 25°C - 35°C and maintain it throughout the preparation - stirring process;

[0048] S2. Preparation of Component A: Put the epoxy resin and polysulfide rubber A into the reaction device according to the dosage, and the feeding order is epoxy resin → polysulfide rubber component A, without pre-stirring, to make component A;

[0049] S3. Preparation of Component B: Put the polysulfide rubber component B into the reaction device, and then add the thickener in three portions gradually. Observe the state of the material. If there is no precipitation or separation phenomenon, then add the reinforcing agent and toughening material to make component B;

[0050] S4. Mixing: Mix component A and component B, and then add the reagents in component C to the mixture of component A and component B in sequence: accelerator → activator → curing agent → defoaming agent, to make the mixture;

[0051] S5. Stirring: The prepared mixture is fully stirred using an electric stirrer. The no-load speed of the stirrer reaches over 1000 r / min, and continuous stirring is carried out for 5 - 10 min. When the materials are completely mixed, the color of the surface of the material liquid is uniform, there is no block precipitation or coagulation, and no layering phenomenon appears, it is determined that the stirring is sufficient, and thus a fluid-shaped polymer elastic composite material for the ballastless track system - the embedded continuous support ballastless track system is made.

[0052] Pour the prepared fluid-shaped polymer elastic composite material for the embedded continuous support ballastless track system into the track support rail groove, let the liquid surface level naturally, and it can meet the operation load-bearing requirements after standing for 3 h.

[0053] The performance parameters of the polymer elastic composite material obtained in this Example 1 are shown in Table 2:

[0054] Table 2 - Performance parameter table of the polymer elastic composite material obtained in Example 1

[0055]

[0056] Example 2:

[0057] A polymer elastic composite material for a ballastless track system, the ballastless track system is an elastic short sleeper integral roadbed. This polymer elastic composite material includes component A, component B, and component C. The component A, component B, and component C respectively include the components shown in Table 3 by weight:

[0058] Table 3 - List of components included in component A, component B, and component C respectively described in Example 2

[0059]

[0060] The preparation method of the polymer elastic composite material for the ballastless track system described in this Example 2 includes the following steps:

[0061] S1. Preparation: Measure the environmental temperature and humidity conditions, check the state of each component raw material. If there is a low-temperature solidification phenomenon, preheat the epoxy resin to 25°C - 35°C and maintain it throughout the preparation - stirring process;

[0062] S2. Preparation of component A: Put the epoxy resin and polysulfide rubber component A into the reaction device according to the dosage. The feeding order is epoxy resin → polysulfide rubber component A, and no pre-stirring is required to make component A;

[0063] S3. Preparation of component B: Put the polysulfide rubber component B into the reaction device, and then add the thickener in three portions gradually. Observe the state of the material. If there is no precipitation or separation phenomenon, then add the reinforcing agent and toughening material to make component B;

[0064] S4. Mixing: Mix components A and B, and then sequentially add the reagents in component C to the mixture of components A and B in the following order: accelerator → activator → curing agent → defoamer to form a mixed material.

[0065] S5. Stirring: Thoroughly stir the prepared mixed material using an electric stirrer. The no-load speed of the stirrer reaches above 1000 r / min, and stir continuously for 5 - 10 min. When the materials are completely mixed, and the color on the surface of the material liquid is uniform, there is no lumpy precipitation or coagulation, and no stratification occurs, it is determined that the stirring is sufficient, thus forming a fluid-like high molecular elastic composite material for the ballastless track system - the elastic short sleeper integral roadbed.

[0066] The performance parameters of the high molecular elastic composite material obtained in Example 2 are shown in Table 4:

[0067] Table 4 - Performance Parameter Table of the High Molecular Elastic Composite Material Obtained in Example 2

[0068]

[0069] Comparative Example 1:

[0070] The difference between Comparative Example 1 and Example 1 is that the SF-66 epoxy resin halogen-free diluent used as the activator is replaced with a KB-62 halogen-free diluent, and the 4A molecular sieve used as the toughening material is replaced with a carbon fiber powder toughening material.

[0071] The remaining weight parts and operation steps are the same as those in Example 1.

[0072] Comparative Example 2:

[0073] The difference between Comparative Example 2 and Example 1 is that the SF-66 epoxy resin halogen-free diluent used as the activator is replaced with a KB-62 halogen-free diluent.

[0074] The remaining weight parts and operation steps are the same as those in Example 1.

[0075] Comparative Example 3:

[0076] The difference between Comparative Example 3 and Example 2 is that the KH-560 silane coupling agent used as the accelerator is replaced with an A-172 silane coupling agent, and the 4A molecular sieve used as the toughening material is replaced with rubber powder.

[0077] The remaining weight parts and operation steps are the same as those in Example 2.

[0078] Comparative Example 4:

[0079] The difference between Comparative Example 4 and Example 2 is that the 4A molecular sieve used as the toughening material is replaced with rubber powder.

[0080] The remaining weight parts and operation steps are the same as those in Example 2.

[0081] Comparative Example 5:

[0082] The only difference between Comparative Example 5 and Example 1 is that the weight part of 4A molecular sieve is changed from 0.05 to 0.025.

[0083] Comparative Example 6:

[0084] The only difference between Comparative Example 5 and Example 1 is that the weight part of 4A molecular sieve is changed from 0.005 to 0.0025.

[0085] The following is a comparative test of Example 1 and Example 2 of the present invention with Comparative Examples 1-6 respectively:

[0086] (1) Performance test

[0087] 1. Static stiffness test

[0088] (1) Static stiffness test of the polymer elastic composite material for the embedded continuous supported ballastless track system

[0089] According to the current national standard GB / T 21527-2008 "Elastic Pads for Rail Fastening Systems", a static stiffness experiment is carried out on the polymer elastic composite material of the embedded continuous supported ballastless track system. The test equipment uses a universal testing machine required by the specification. The specimen size is converted with the same stress, and the size is 200mm×180mm. The loading speed is 2kN / s to 3kN / s. Each group of specimens needs to be tested in parallel three times. When the load is applied to F1 (5kN) and F2 (35kN), the displacements of the displacement sensors are recorded respectively. Calculate the average values of D 1i 、D 2i , and calculate the static stiffness of the specimen using the following formula:

[0090]

[0091] Among them:

[0092] F1 - The lower limit load calculated for the static stiffness test of the standard specimen, that is, 5kN;

[0093] F2 - The upper limit load calculated for the static stiffness test of the standard specimen, that is, 35kN;

[0094] D 1i - The displacement of the standard specimen when loaded to F1 in each group of parallel tests, in mm;

[0095] D 2i - The displacement of the standard specimen when loaded to F2 in each group of parallel tests, in mm;

[0096] The test results are shown in Table 5:

[0097] Table 5 - List of Static Stiffness Test Results of Polymer Elastic Composite Materials for Embedded Continuous Supported Ballastless Track System

[0098] Example 1 Comparative Example 1 Comparative Example 2 Static stiffness (kN / mm) 31.61 44.45 34.31

[0099] Since the application scenario of Example 1 is the embedded continuous supported ballastless track system, according to the requirements of urban rail transit train wheel-rail axle load and shock absorption, the static stiffness of the elastic plates of WJ-7 and WJ-8 type spring fasteners used shall not be less than 20 kN / mm and not greater than 40 kN / mm.

[0100] It is proved that using SF-66 halogen-free diluent can improve the performance of cross-linked epoxy resin, making it more elastic. At the same time, it can also accelerate the cross-linking reaction and gel in a shorter time. The comparison results show that Example 1 can meet the static stiffness requirements of fasteners for urban rail transit, that is, it can meet the requirements of bearing the train axle load.

[0101] (2) Static Stiffness Test of Polymer Elastic Composite Materials for Elastic Short Sleeper Monolithic Ballastless Track

[0102] According to the current national standard GB / T 21527-2008 "Elastic Pads for Rail Fastening Systems in Rail Transit", the test equipment uses a universal testing machine required by the specification. The standard specimens are stress-converted according to TB / T 2629-2023 "Concrete Elastic Sleepers for Ballasted Railways", and the size is 200 mm × 200 mm.

[0103] Since the application scenario of Example 2 is the elastic short sleeper monolithic ballastless track, referring to the calculation method of the static modulus of the elastic pad under the sleeper specified in TB / T 2629-2023 "Concrete Elastic Sleepers for Ballasted Railways", the following formula is used:

[0104]

[0105] Wherein:

[0106] F1 - Lower limit load for calculating the static modulus of the tested elastic pad

[0107] F2 - Upper limit load for calculating the static modulus of the tested elastic pad

[0108] D1 - Displacement of the tested elastic pad when loaded to F1, in mm

[0109] D2 - Displacement of the tested elastic pad when loaded to F2, in mm

[0110] A - Area of the single elastic pad or the elastic pad on the concrete block, 62500 mm 2 ;

[0111] C sta —— Static modulus, with the unit of Newton per cubic millimeter (N / mm 3 ).

[0112] According to the requirements of the static modulus specified in TB / T 2629-2023 "Concrete Elastic Sleepers for Ballasted Railway Tracks", the static stiffness requirements of elastic short sleepers can be calculated by the following formula:

[0113]

[0114] Where:

[0115] C sta —— Static modulus, with the unit of Newton per cubic millimeter (N / mm 3 );

[0116] A - The area of a single elastic pad or the elastic pad on a concrete block, 62500 mm 2 .

[0117] According to the above formula, the static stiffness of the polymer elastic composite material of the elastic short sleeper integral ballast bed should be 15 kN / mm to 20 kN / mm. The static stiffness test method is as follows:

[0118] Conduct tests on the static stiffness of the polymer elastic composite material of the elastic short sleeper integral ballast bed according to the current national standard GB / T 21527-2008 "Elastic Pads for Rail Fastening Systems in Rail Transit". The test equipment uses a universal testing machine required by the specification. The specimen size is converted with the same stress, and the size is 200 mm × 200 mm. The loading speed is 2 kN / s to 3 kN / s. Each group of specimens needs to conduct parallel tests three times. When the load is applied to F1 (5 kN) and F2 (35 kN), record the displacements of the displacement sensors respectively. Calculate the average values of D 1i , D 2i . The static stiffness of the specimen is calculated by the following formula:

[0119]

[0120] Where:

[0121] F1 - The lower limit load for calculating the static stiffness test of the standard specimen, that is, 5 kN;

[0122] F2 - The upper limit load for calculating the static stiffness test of the standard specimen, that is, 35 kN;

[0123] D 1i —— The displacement of the standard specimen when loaded to F1 in each group of parallel tests, with the unit of mm;

[0124] D 2i—— Displacement when the standard specimen in each group of parallel tests is loaded to F2, unit: mm;

[0125] The test results are shown in Table 6:

[0126] Table 6 - Summary of test results for static stiffness test of polymer elastic composite materials used in elastic short sleeper monolithic track beds

[0127] Example 2 Comparative Example 3 Comparative Example 4 Static stiffness (kN / mm) 13.58 29.05 32.07

[0128] It can be seen from Table 6 that KH-560 silane coupling agent is an excellent adhesion promoter, which can improve the wettability and adhesion of materials. At the same time, 4A molecular sieve can improve the agglomeration phenomenon of ultrafine particles and the problems of insufficient modification and uneven dispersion, and is helpful for increasing the elasticity of materials.

[0129] 2. Dynamic stiffness test

[0130] (1) Dynamic stiffness test of polymer elastic composite materials used in embedded continuous supported ballastless track systems

[0131] According to the current national standard GB / T 21527-2008 "Elastic pads for rail fastening systems in rail transit", a dynamic stiffness experiment is carried out on the polymer elastic composite materials of the embedded continuous supported ballastless track system. The test equipment uses a servo fatigue testing machine required by the specification. The specimen size is converted with the same stress, and the size is 200mm×180mm. The loading frequency is 5Hz, and the load is cycled 1000 times from 5kN to 35kN. When the load is applied to F1 (5kN) and F2 (35kN), the values of the displacement sensors are monitored, and the D 1i 、D 2i values of each group of cycles are calculated, and the dynamic stiffness of each group of cycles of the specimen is calculated and the average value is obtained using the following formula:

[0132]

[0133] Where:

[0134] F1 - Lower limit load calculated from the static stiffness test of the standard specimen, i.e., 5kN;

[0135] F2 - Upper limit load calculated from the static stiffness test of the standard specimen, i.e., 35kN;

[0136] D 1i —— Displacement when the standard specimen in each group of parallel tests is loaded to F1, unit: mm;

[0137] D 2i —— Displacement when the standard specimen in each group of parallel tests is loaded to F2, unit: mm;

[0138] K 动i——The dynamic stiffness of the standard specimen in each group of cycles, unit: kN / mm;

[0139] The test results of dynamic stiffness are shown in Table 7:

[0140] Table 7—Summary of dynamic stiffness test for polymer elastic composite materials used in embedded continuous supported ballastless track systems

[0141] Example 1 Comparative Example 1 Comparative Example 2 Dynamic stiffness (kN / mm) 33.04 60.73 56.95

[0142] The results of the dynamic-to-static stiffness ratio are shown in Table 8:

[0143] Table 8—Summary of the results of the dynamic-to-static stiffness ratio

[0144] Example 1 Comparative Example 1 Comparative Example 1 Ratio of dynamic stiffness to static stiffness 1.05 1.37 1.66

[0145] Since the application scenario of Example 1 is an embedded continuous supported ballastless track system, according to the requirements of urban rail transit train wheel-rail axle load and shock absorption, the static stiffness of the elastic plates of WJ-7 and WJ-8 type spring fasteners used shall not be less than 1 and not greater than 1.5. However, since this material is a monolithic casting material, referring to the actual intercity rail transit engineering examples, it is proved that the viscoelastic hysteresis of the elastomer is beneficial to its shock absorption performance, and the closer the dynamic-to-static stiffness ratio is to 1, the better its vibration transmission characteristics are.

[0146] From the comparison of the dynamic stiffness values and the dynamic-to-static stiffness ratios, it can be concluded that:

[0147] Using SF-66 epoxy resin halogen-free diluent can improve the performance of cross-linked epoxy resin, making it have better elasticity.

[0148] Using 4A molecular sieve to replace carbon fiber toughening material can adsorb or repel molecules of different substances according to the size of the pores inside its crystal, making the molecular gap closer and providing the material with rapid rebound ability, meeting the requirements of the dynamic load amplitude during train operation.

[0149] (2) Dynamic stiffness test of polymer elastic composite materials for elastic short sleeper monolithic track bed

[0150] According to the current national standard GB / T 21527-2008 "Elastic Pads for Rail Fastening Systems in Rail Transit", a dynamic stiffness experiment is carried out on the polymer elastic composite materials for elastic short sleeper monolithic track bed. The test equipment uses a servo fatigue testing machine required by the specification. The specimen size is converted with the same stress, and the size is 200mm×200mm. Referring to the calculation method of the fatigue performance test of elastic short sleepers specified in TB / T 2629-2023 "Concrete Elastic Sleepers for Ballasted Railways", the loading frequency is 5Hz, and the load is cycled 1000 times from 5kN to 35kN. When the monitoring load is applied to F1 (5kN) and F2 (35kN), the values of the displacement sensors are used to calculate D for each group of cycles1i , D 2i value, and calculate the dynamic stiffness of each group of cycles of the test piece and obtain the average value using the following formula:

[0151]

[0152] Where:

[0153] F1—the lower limit load calculated in the static stiffness test of the standard test piece, i.e., 5 kN;

[0154] F2—the upper limit load calculated in the static stiffness test of the standard test piece, i.e., 35 kN;

[0155] D 1i —the displacement when the standard test piece is loaded to F1 in each group of parallel tests, in mm;

[0156] D 2i —the displacement when the standard test piece is loaded to F2 in each group of parallel tests, in mm;

[0157] K 动i —the dynamic stiffness of the standard test piece in each group of cycles, in kN / mm;

[0158] The test results of dynamic stiffness are shown in Table 9:

[0159] Table 9—Summary of test results of dynamic stiffness of polymer elastic composite materials for elastic short sleeper integral ballast bed

[0160] Example 2 Comparative Example 3 Comparative Example 4 Dynamic stiffness (kN / mm) 17.31 33.03 21.07

[0161] The results of the dynamic-to-static stiffness ratio are shown in Table 10:

[0162] Table 10—Summary of results of dynamic-to-static stiffness ratio

[0163] Example 2 Comparative Example 3 Comparative Example 4 Ratio of dynamic stiffness to static stiffness 1.27 1.14 0.66

[0164] Since the application scenario of Example 2 is an elastic short sleeper integral ballast bed, which is mainly set in medium vibration reduction sections, the existing elastic short sleepers mainly rely on the rubber boots between the short sleepers and the ballast bed to provide elastic buffering. According to the requirements of the TB / T 2629-2023 "Concrete Elastic Sleepers for Ballast Tracks", the dynamic-to-static stiffness ratio shall not be greater than 1.35 and shall not be less than 1.

[0165] From the comparison of the dynamic stiffness values and the dynamic-to-static stiffness ratio values, it can be concluded that:

[0166] Using KH-560 silane coupling agent can improve the dispersibility and reinforcement of the filler, providing greater elasticity for the material.

[0167] Using 4A molecular sieve to replace the rubber powder toughening material can provide elasticity for the material under high-frequency loads without large displacement amplitudes, meeting the requirements of vibration reduction and support for elastic short sleepers.

[0168] At the same time, the existing elastic short sleepers adopt a mode of one set of boots and one bed. There will be gaps between the boots in the pit and the pit wall, and between the boots and the bottom of the short sleeper. Therefore, the vibration reduction effect of the track is unstable, and it may even lead to the failure of the elastic boots or amplify the impact of the sleeper to cause the vibration of the roadbed. Seriously, the problem of sleeper rupture will occur. Therefore, this material adopts a construction method of one-time continuous casting and forming. Through the self-fluidity of the liquid material, a continuous, dense and tightly attached integrated elastic restraint material can be formed, thus effectively avoiding the above disadvantages of the boots.

[0169] (2) Fatigue test

[0170] (1) Fatigue test of the polymer elastic composite material for the embedded continuous support ballastless track system

[0171] According to the current national standard GB / T 21527-2008 "Elastic pads for rail fastening systems in rail transit", a static stiffness experiment is carried out on the polymer elastic composite material for the embedded continuous support ballastless track system. The test equipment uses a servo fatigue testing machine required by the specification. The specimen size is converted with the same stress, with a size of 200mm×180mm, a loading frequency of 5Hz, and a load of 5kN - 35kN for 1×10 6 times. A displacement sensor with a precision of 0.01mm is used to monitor the maximum and minimum displacement amplitudes of the material during the fatigue test.

[0172] The test results are shown in Table 11 and Table 12:

[0173] Table 11 - Comparison table of static and dynamic stiffness before and after fatigue of Example 1 and Comparative Example 5

[0174] Static stiffness Dynamic stiffness Static stiffness after fatigue Dynamic stiffness after fatigue Example 1 31.61 33.04 35.45 41.92 Comparative Example 5 24.84 25.88 27.86 29.57

[0175] Table 12 - Comparison table of dynamic and static stiffness ratios before and after fatigue of Example 1 and Comparative Example 5

[0176] Ratio of dynamic stiffness to static stiffness Ratio of dynamic stiffness to static stiffness after fatigue Ratio of static stiffness before and after fatigue Ratio of dynamic stiffness before and after fatigue Example 1 1.05 1.18 1.12 1.33 Comparative Example 5 1.04 1.06 1.12 1.19

[0177] Through comparison, it is found that due to the different dosages of 4A molecular sieve in Example 1 and Comparative Example 5, there are significant differences in their static and dynamic stiffness. After 1×10^6 cycles of load, there are no significant changes in the dynamic and static stiffness of the two groups of materials before and after the fatigue test. At the same time, by comparing the dynamic and static stiffness ratios before and after fatigue, it is concluded that the overall condition of the material is relatively good and the material performance is stable.

[0178] According to the stiffness requirements of the national standard GB / T 21527-2008 "Elastic Pads for Rail Transit Fastening Systems", the optimal mass ratio of the 4A molecular sieve component in the polymer elastic composite material of the embedded continuous supported ballastless track system is 1:2000.

[0179] (2) Fatigue test of polymer elastic composite material for elastic short sleeper integral roadbed

[0180] According to the current national standard GB / T 21527-2008 "Elastic Pads for Rail Transit Fastening Systems", a static stiffness experiment was carried out on the polymer elastic composite material of the embedded continuous supported ballastless track system. The test equipment used a servo fatigue testing machine required by the specification. The specimen size was converted with the same stress, and the size was 200mm×200mm. The loading frequency was 5Hz, and the load was 5kN - 35kN for 1×10 6 cycles. A displacement sensor with an accuracy of 0.01 was used to monitor the maximum and minimum displacement amplitudes of the material during the fatigue test.

[0181] The test results are shown in Table 13:

[0182] Table 13 - Comparison table of dynamic and static stiffness before and after fatigue of Example 2 and Comparative Example 6

[0183] Static stiffness Dynamic stiffness Static stiffness after fatigue Dynamic stiffness after fatigue Example 2 13.58 17.31 14.75 18.01 Comparative Example 6 12.83 18.02 12.82 19.19

[0184] Table 14 - Comparison table of dynamic and static stiffness ratios before and after fatigue of Example 2 and Comparative Example 6

[0185] Ratio of dynamic stiffness to static stiffness Ratio of dynamic stiffness to static stiffness after fatigue Ratio of static stiffness before and after fatigue Ratio of dynamic stiffness before and after fatigue Example 2 1.27 1.22 1.09 1.05 Comparative Example 6 1.41 1.49 0.99 1.06

[0186] By comparison, although the dosages of 4A molecular sieves in Example 2 and Comparative Example 6 are different, since the proportion change in the overall material is relatively small, there is no significant change in the dynamic and static stiffness of the two groups of materials. After 1×10 6 cycles of cyclic load, there is no significant change in the dynamic and static stiffness of the two groups of materials before and after the fatigue test. At the same time, by comparing the dynamic and static stiffness ratios before and after fatigue, it is concluded that the overall condition of the material is relatively good and the material performance is stable, but in Comparative Example 6, the static stiffness decreases after the fatigue test.

[0187] Therefore, according to the stiffness requirements of TB / T 2629-2023 "Concrete Elastic Sleepers for Ballasted Railways", the optimal mass ratio of the 4A molecular sieve component in the polymer elastic composite material of the elastic short sleeper integral roadbed is 1:20000.

[0188] (3) Time boundary condition test

[0189] According to the operation, maintenance, and inspection requirements of urban rail transit, a series of operations such as inspection, repair, and replacement need to be completed in a short period of time. Therefore, the time boundary conditions are particularly important for the polymer elastic composite materials of the embedded track system.

[0190] Proceeding from engineering practice, the following requirements are put forward for the time boundary conditions of the materials:

[0191] (1) The initial setting time of the polymer elastic constraint material is 3h, the strength is 60Mpa ± 5Mpa, the final setting time is 1d, and the strength is 85Mpa ± 10Mpa;

[0192] (2) The polymer constraint material can be continuously poured, and the pouring time must be controlled within 3h to ensure good bonding and stability.

[0193] The curing tests were carried out on Example 1, Example 2, Comparative Example 1, Comparative Example 2, Comparative Example 3, Comparative Example 4, Comparative Example 5, and Comparative Example 6. The test results are shown in Table 15:

[0194] Table 15 - Test Results of Curing

[0195]

[0196] It can be seen from Table 15 that the materials in the above groups can all meet the requirement of curing within 3h.

[0197] Example 3, Example 4:

[0198] The following are Example 3 and Example 4 of the present invention, the polymer elastic composite materials with different component contents for the embedded continuous supported ballastless track system and their preparation methods:

[0199] Similar to Example 1, the ballastless track system described in Example 3 and Example 4 is an embedded continuous supported ballastless track system. The polymer elastic composite material includes Component A, Component B, and Component C. The difference is that the Component A, Component B, and Component C and their weight parts have changed, and the details are shown in Table 16 and Table 17.

[0200] Table 16 - List of Components Included in Component A, Component B, and Component C Described in Example 3

[0201]

[0202] Table 17 - List of Components Included in Component A, Component B, and Component C Described in Example 4

[0203]

[0204] Example 5, Example 6:

[0205] The following are Embodiment 5 and Embodiment 6 of the present invention, a polymer elastic composite material for an embedded continuous supported ballastless track system with different component contents and its preparation method:

[0206] Similar to Embodiment 2, the ballastless track system described in Embodiment 5 and Embodiment 6 is an elastic short sleeper integral roadbed. The polymer elastic composite material includes Component A, Component B, and Component C. The difference lies in that the Component A, Component B, and Component C and their weight parts have changed, and the details are shown in Table 18 and Table 19.

[0207] Table 18 - List of components included in Component A, Component B, and Component C described in Embodiment 5

[0208]

[0209]

[0210] Table 19 - List of components included in Component A, Component B, and Component C described in Embodiment 6

[0211]

[0212] As a variation of Embodiment 1 to Embodiment 6,

[0213] In Component A, the weight part of epoxy resin can take any value in the range of 15 - 18 parts, and the weight part of polythiol rubber in Component A can take any value in the range of 15 - 18 parts;

[0214] In Component B, the weight part of polythiol rubber in Component B can take any value in the range of 33 - 38 parts, the weight part of the thickening agent can take any value in the range of 15 - 18 parts, the weight part of the toughening material can take any value in the range of 0.005 - 0.05 parts, and the weight part of the reinforcing agent can take any value in the range of 0.3 - 0.8 parts;

[0215] In Component C, the weight part of the accelerator can take any value in the range of 1.2 - 1.8 parts, the weight part of the activator can take any value in the range of 1.5 - 1.8 parts, the weight part of the curing agent can take any value in the range of 1.0 - 2.0 parts, and the weight part of the defoaming agent can take any value in the range of 0.1 - 0.3 parts.

[0216] As another variation of Embodiment 1 to Embodiment 6, Additive A is composed of one or more of dibutyl phthalate, chlorinated biphenyl, chlorinated paraffin, butyl benzyl phthalate, alkylbenzene compounds, sulfur-containing organic amine compounds, ethylenediamine compounds, diphenyl guanidine, tetramethyl thiuram disulfide, and benzothiazole disulfide in any ratio combination.

[0217] The additive B is composed of one or more of the condensates of dichloroethane and alkali metal tetrasulfides, dichloroethane, the condensates of bis-2-chloroethyl formal and alkali metal disulfides, bisdichloroethylene formal, and the condensates of trichloropropane and alkali metal polysulfides, combined in any ratio.

[0218] As yet another variation of Examples 1 to 6,

[0219] The thickener is composed of one or more of organosilane compounds, alkylphenolic resins, and nonionic associative thickeners, combined in any ratio; the toughening material is composed of one or more of hydrated aluminosilicates, natural zeolites, and rubber powder, combined in any ratio; the reinforcing agent is composed of one or more of precipitated silica, fumed silica, and ultrafine silica gel, combined in any ratio.

[0220] As yet another variation of Examples 1 to 6,

[0221] The promoter is composed of one or more of vinyltris(β-methoxyethoxy)silane, γ-glycidoxypropyltrimethoxysilane, γ-aminopropyltriethoxysilane, and 3-(methacryloyloxy)propyltrimethoxysilane, combined in any ratio; the activator is composed of one or more of the halogen-free epoxy resin diluents SF-66, HK-66, HS-62, and S-7400, combined in any ratio; the curing agent is composed of one or more of dimethylamine, 2,4,6-tris(dimethylaminomethyl)phenol, 4-hydroxybenzoic acid, ethylenediamine, hexamethylenediamine, and diethylenetriamine, combined in any ratio; the defoamer is composed of one or more of modified polysiloxanes and polyether-modified organosilicons, combined in any ratio.

Claims

1. A polymer elastic composite material for a ballastless track system, characterized in that: It includes component A, component B and component C. The A component comprises, by weight: Epoxy resin, 15-18 parts, Polysulfide rubber A component, 33-38 parts; The B component comprises, by weight: The C component comprises by weight:

2. The polymer elastic composite material for ballastless track system according to claim 1, characterized in that: The epoxy resin is bisphenol A type epoxy resin (E-03 type).

3. The polymer elastic composite material for ballastless track system according to claim 1, characterized in that: The polysulfide rubber component A uses polysulfide prepolymer as the main agent, and is added with additive A, wherein the weight ratio of the main agent to the additive A is 3:1; the additive A is composed of one or more of dibutyl phthalate, chlorinated biphenyl, chlorinated paraffin, butyl benzyl phthalate, alkylbenzene compounds, sulfur-containing organic amino compounds, ethylene polyamine compounds, diphenyl guanidine, tetramethylthiuram sulfide, and benzothiazole disulfide in any combination.

4. The polymer elastic composite material for ballastless track system according to claim 1, characterized in that: The polysulfide rubber component B is composed of a plasticizer as the main agent and an additive B, wherein the weight ratio of the main agent to the additive B is 1.5:1; the additive B is composed of one or more of a condensation product of ethylene dichloride and alkali metal tetrasulfide, a condensation product of ethylene dichloride, bis-2-chloroethyl formal and alkali metal disulfide, bis(dichlorovinyl) formal, and a condensation product of trichloropropane and alkali metal polysulfide, in any proportion.

5. The polymer elastic composite material for ballastless track system according to claim 1, characterized in that: The thickener is composed of one or more of an organic silane compound, an alkyl phenolic resin and a nonionic associative thickener in any proportion.

6. The polymer elastic composite material for ballastless track system according to claim 1, characterized in that: The tough material is composed of one or more of hydrated aluminosilicate, natural zeolite and rubber powder in any proportion.

7. The polymer elastic composite material for ballastless track system according to claim 1, characterized in that: The reinforcing agent is composed of one or more of precipitated silica, fumed silica and ultrafine silica gel in any proportion.

8. The polymer elastic composite material for ballastless track system according to claim 1, characterized in that: The accelerator is one or more of vinyl tri(β-methoxyethoxy)silane, γ-glycidyloxypropyl trimethoxysilane, γ-aminopropyl triethoxysilane, and 3-(methacryloyloxy)propyl trimethoxysilane in any combination; the activator is one or more of epoxy resin halogen-free diluent SF-66, HK-66, HS-62, and S-7400 in any combination.

9. The polymer elastic composite material for ballastless track system according to claim 1, characterized in that: The curing agent is one or more of dimethylamine, 2,4,6-tris(dimethylaminomethyl)phenol, 4-hydroxybenzoic acid, ethylenediamine, hexamethylenediamine, and diethylenetriamine in any proportion; the defoaming agent is one or more of modified polysiloxane and polyether-modified silicone in any proportion.

10. A method for preparing a polymer elastic composite material for a ballastless track system according to any one of claims 1 to 9, characterized in that: The steps include: S1. Preparation: Measure the ambient temperature and humidity, check the status of each component raw material, and if low-temperature solidification occurs, preheat the epoxy resin to 25°C to 35°C and continue the entire preparation-stirring process; S2. Preparation of component A: According to the amount, the epoxy resin and polysulfide rubber A are put into the reaction device in order to prepare component A; S3. Preparation of component B: The polysulfide rubber component B is put into the reaction device, and then the thickener is added in small amounts, and the state of the material is observed. If there is no precipitation or precipitation, a reinforcing agent and a toughening material are added in order to prepare component B; S4. Mixing: Mix components A and B, and then add the reagents in component C to the mixture of components A and B in the following order: accelerator → activator → curing agent → defoaming agent to prepare a mixture; S5. Mixing: The prepared mixture is fully stirred with an electric stirrer, and the no-load speed of the stirrer reaches more than 1000r / min. Stirring is continued for 5 to 10 minutes. When the materials are completely mixed, and the surface color of the material liquid is uniform, there is no lumpy precipitation or coagulation, and no stratification, it is judged that the stirring is sufficient, that is, a fluid polymer elastic composite material for ballastless track system is produced.

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