A method for preparing a vibration-absorbing ballastless track slab

Abstract

A method for preparing a shock-absorbing ballastless track slab, characterized in that it includes a track slab, an adhesive layer, an elastomer, an adhesion layer and a base, which are sequentially distributed from top to bottom; the preparation method is as follows: S1, cleaning the bottom surface of the track slab and the surface of the base to make them dry, clean, and free of dust, debris or residual chemical materials; S2, bonding the elastomer to the surface of the base, wherein each base needs to be configured with two elastomers to support the base; S3, wrapping the elastomer with a prefabricated foam fence; S4, placing the track slab on the prefabricated foam fence, at this time, an adhesive layer injection cavity is formed between the prefabricated foam fence, the track slab and the elastomer; the advantages of the present invention are: using elastomer to fill under the track slab as a shock-absorbing material, suitable for the design of low-rigidity shock-absorbing fasteners for urban rail, the design of a convenient prefabricated limiting structure, and the fully automatic rapid on-site injection equipment technology suitable for on-site construction of multi-component glue.

Description

Technical Field

[0001] The invention relates to the field of track construction, and in particular to a method for preparing a shock-absorbing ballastless track slab. Background Art

[0002] At present, urban rail transit has become a hot spot for development and construction in major cities around the world with its advantages of convenience, speed, punctuality, energy saving, and effective relief of ground traffic congestion. According to statistics, in the urban rail transit operation and under-construction lines in Beijing, the track structure generally adopts ballastless track. According to different needs, elastic long pillow type, trapezoidal sleeper type, floating plate type and other vibration-reducing ballastless track are adopted in the vibration reduction section. The track structure types in other urban rail transit are similar. Therefore, the scale of ballastless track construction in my country's urban rail transit industry will be relatively large in the future. The existing shock-absorbing technical solutions are generally for EPDM foam materials and ethylene vinyl acetate (EVA) foam materials. EPDM foam materials are semi-general synthetic rubbers with a service temperature range of -55 to 150 °C. Because its main chain is composed of chemically stable saturated hydrocarbons and only contains unsaturated double bonds in the side chain, it has outstanding resistance to ozone, weather, water, steam, and chemicals (such as ammonia, alcohol, hydrogen peroxide, salt, sulfuric acid, caustic soda, lime, etc.), and can be widely used in automotive parts,

[0003] It is used in building waterproof materials, wire and cable sheaths, heat-resistant hoses, tapes, automotive seals and other fields. However, its aging resistance, high temperature resistance, dynamic and static stiffness are relatively poor, so it is not suitable to be selected as a shock-absorbing material.

[0004] EVA foam is made by copolymerization of ethylene (E) and vinyl acetate (VA). It has good softness, rubber-like elasticity, good flexibility, transparency and surface gloss at 0°C, good chemical stability, and good anti-aging and ozone resistance. It is widely used in foam slippers, sandals, building materials, etc. Injection foaming has various industrial parts, women's soles, etc. Due to its good plasticity, the foam material has strong water absorption performance and poor high temperature resistance. If it is specially treated, the price is very expensive, and the composite performance with other materials is poor, so it is not suitable for special environments.

[0005] Based on the previous construction and operation experience, the following problems exist in the construction of urban rail transit tracks in my country: 1. Cast-in-place concrete construction is the main method, and the construction efficiency is low; 2. The quality of cast-in-place concrete is difficult to control, and the durability problem is more prominent; 3. It is directly connected to the lower foundation and has poor maintainability. Summary of the invention

[0006] The purpose of the present invention is to provide a method for preparing a vibration-absorbing ballastless track slab in view of the above-mentioned shortcomings.

[0007] The present invention comprises a track plate, an adhesive layer, an elastic body, an adhesive layer and a base which are sequentially arranged from top to bottom;

[0008] The preparation method is as follows:

[0009] S1. Clean the bottom surface of the track plate and the base surface to make them dry, clean, and free of dust, debris or residual chemical materials;

[0010] S2, bonding the elastic body to the surface of the base, wherein each base needs to be equipped with two elastic bodies to support the base;

[0011] S3, wrapping the elastomer with a prefabricated foam fence;

[0012] S4, placing the track plate on the prefabricated foam fence, at which point an adhesive layer perfusion cavity is formed between the prefabricated foam fence, the track plate and the elastomer;

[0013] S5. Pour the three components of adhesive into the mixing barrel according to the proportion of the mixing ratio, stir them thoroughly to make them evenly mixed, the stirring time is 3-5 minutes, use mechanical method to stir, the electric stirrer stirs thoroughly up and down, left and right, the speed should be 300-2000 rpm, after the mixture is stirred, let it stand for 1 minute, and then divide the stirred mixture into the filling container;

[0014] S6. At 5℃-35℃, pour the adhesive into the adhesive layer through the pouring hole on the track plate, until the entire adhesive layer is filled. After the pouring is completed, close the pouring hole and wait for curing. The curing time is 12-48 hours.

[0015] S7. Remove the prefabricated foam fence to complete the production of the shock-absorbing ballastless track slab.

[0016] Further, the preparation method is as follows:

[0017] Prefab:

[0018] S1. Clean the bottom surface of the track plate and the base surface to make them dry, clean, and free of dust, debris or residual chemical materials;

[0019] S2, bonding the elastic body to the surface of the base, wherein each base needs to be equipped with two elastic bodies to support the base, thus obtaining a base with an elastic body;

[0020] forming:

[0021] S3, placing the base with the elastic body at the required construction site, and wrapping the elastic body with a prefabricated foam fence;

[0022] S4, placing the track plate on the prefabricated foam fence, at which point an adhesive layer perfusion cavity is formed between the prefabricated foam fence, the track plate and the elastomer;

[0023] S5. Pour the three components of adhesive into the mixing barrel according to the proportion of the mixing ratio, stir them thoroughly to make them evenly mixed, the stirring time is 3-5 minutes, use mechanical method to stir, the electric stirrer stirs thoroughly up and down, left and right, the speed should be 300-2000 rpm, after the mixture is stirred, let it stand for 1 minute, and then divide the stirred mixture into the filling container;

[0024] S6. At 5℃-35℃, pour the adhesive into the adhesive layer through the pouring hole on the track plate, until the entire adhesive layer is filled. After the pouring is completed, close the pouring hole and wait for curing. The curing time is 12-48 hours.

[0025] S7. Remove the prefabricated foam fence and complete the production of the shock-absorbing ballastless track slab at the construction site.

[0026] Furthermore, the height of the elastic body is 30MM, and the height of the adhesive layer is 10MM.

[0027] Furthermore, the adhesive layer is a three-component adhesive.

[0028] Further, the elastomer comprises the following components in parts by weight:

[0029] Polyamide thermoplastic elastomer 200 parts

[0030] 100 parts of nitrile rubber

[0031] 5 parts paraffin

[0032] 35 parts of semi-reinforced carbon black

[0033] 4 parts of dicumyl peroxide

[0034] 4 parts of antioxidant

[0035] 1.5 parts of isonicotinamide

[0036] 4 parts of 2,6-difluoro-4-bromoiodobenzene.

[0037] The specific steps are as follows:

[0038] S1, heating the above-mentioned parts by weight of the polyamide thermoplastic elastomer and the nitrile rubber to 130-135° C., dehydrating under vacuum, adding the above-mentioned parts by weight of isonicotinamide and 2,6-difluoro-4-bromoiodobenzene, continuing to stir and heating to 140-145° C.;

[0039] S2. Add the above-mentioned weight parts of paraffin wax, semi-reinforcing carbon black, dicumyl peroxide and antioxidant to the mixture of S1, pour into a mold, raise the temperature to 160-165° C. and continue mixing and stirring for 2-4 hours to obtain an elastomer.

[0040] Further, the adhesive comprises the following components in parts by weight:

[0041] Component A

[0042] Isocyanate 22 parts

[0043] 32 parts of polyether polyol

[0044] Component B

[0045] Polyol 7 parts

[0046] Chain extender 6 parts

[0047] 1.2 parts of anti-aging agent

[0048] 1.1 parts of UV protection agent

[0049] Color paste 0.6 parts

[0050] Boron carbide powder 1.3 parts

[0051] Component C

[0052] 1.8 parts of magnesium hydroxide whisker

[0053] 2.2 parts of Al2O3-Y2O3 whiskers.

[0054] Further, the preparation method of Al2O3-Y2O3 whiskers is:

[0055] Aluminum nitrate is dissolved in distilled water to prepare a solution with a concentration of 0.5-2.0 mol / L; urea in an amount of 2-10 times the molar amount of aluminum nitrate is added to the aluminum nitrate solution, and stirred evenly at room temperature to obtain a transparent and clear sol; the prepared sol is then placed in a reaction kettle, and maintained at 90-120° C. for 6-12 hours to obtain a white precipitate of an aluminum oxide whisker precursor; the white precipitate is then washed with distilled water, and then calcined at 1100-1300° C. for 2-12 hours to obtain an aluminum oxide whisker;

[0056] Alumina whiskers are added to an aqueous solution of polyvinyl alcohol to prepare a suspension with a solid content of 20wt%, an aqueous solution of yttrium nitrate hexahydrate is added to the suspension to obtain a mixed solution, the pH of the mixed solution is adjusted to 8, yttrium hydroxide is deposited on the surface of the alumina whiskers to form a precipitate, the precipitate is filtered, cleaned and then calcined to obtain Al2O3-Y2O3 whiskers.

[0057] Furthermore, the calcination temperature is 1350-1400° C., and the calcination time is 2-4 hours.

[0058] Furthermore, a weakly alkaline substance is selected to adjust the pH of the mixed solution, which may be aqueous ammonia, sodium carbonate or sodium bicarbonate.

[0059] Furthermore, the polyether polyol is polytetrahydrofuran or polyethylene oxide or polypropylene oxide polyol.

[0060] The advantages of the present invention are: using elastomer to fill under the track plate as a vibration-damping material, suitable for the design of low-rigidity vibration-damping fasteners for urban rail, the design of a convenient prefabricated limiting structure, and full-automatic rapid on-site pouring equipment technology suitable for on-site construction of multi-component adhesives. A new plate-type ballastless track system based on on-site polyurethane pouring is developed, which will effectively solve or alleviate the problems of high cost of vibration and noise control measures and long construction period of cast-in-place ballastless track in the construction link of urban rail transit ballastless track, and promote the development of urban rail transit across the country. BRIEF DESCRIPTION OF THE DRAWINGS

[0061] Figure 1 It is a schematic diagram of the structure of the present invention.

[0062] Figure 2 It is a side view structural schematic diagram of the present invention. DETAILED DESCRIPTION

[0063] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings here can be arranged and designed in various different configurations.

[0064] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0065] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0066] In the description of the embodiments of the present invention, it should be noted that if the terms "upper", "lower", "inner", "outer", etc. appear, the orientation or position relationship indicated is based on the orientation or position relationship shown in the drawings, or the orientation or position relationship in which the product of the invention is usually placed when in use. This is only for the convenience of describing the present invention and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention. In addition, if the terms "first", "second", etc. appear in the description of the present invention, they are only used to distinguish the description and cannot be understood as indicating or implying relative importance.

[0067] In the description of the embodiments of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "setting" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0068] It includes a track plate, an adhesive layer, an elastic body, an adhesive layer and a base arranged in sequence from top to bottom;

[0069] The preparation method is as follows:

[0070] S1. Clean the bottom surface of the track plate and the base surface to make them dry, clean, and free of dust, debris or residual chemical materials;

[0071] S2, bonding the elastic body to the surface of the base, wherein each base needs to be equipped with two elastic bodies to support the base;

[0072] S3, wrapping the elastomer with a prefabricated foam fence;

[0073] S4, placing the track plate on the prefabricated foam fence, at which point an adhesive layer perfusion cavity is formed between the prefabricated foam fence, the track plate and the elastomer;

[0074] S5. Pour the three components of adhesive into the mixing barrel according to the proportion of the mixing ratio, stir them thoroughly to make them evenly mixed, the stirring time is 3-5 minutes, use mechanical method to stir, the electric stirrer stirs thoroughly up and down, left and right, the speed should be 300-2000 rpm, after the mixture is stirred, let it stand for 1 minute, and then divide the stirred mixture into the filling container;

[0075] S6. At 5℃-35℃, pour the adhesive into the adhesive layer through the pouring hole on the track plate, until the entire adhesive layer is filled. After the pouring is completed, close the pouring hole and wait for curing. The curing time is 12-48 hours.

[0076] S7. Remove the prefabricated foam fence to complete the production of the shock-absorbing ballastless track slab.

[0077] Further, the preparation method is as follows:

[0078] Prefab:

[0079] S1. Clean the bottom surface of the track plate and the base surface to make them dry, clean, and free of dust, debris or residual chemical materials;

[0080] S2, bonding the elastic body to the surface of the base, wherein each base needs to be equipped with two elastic bodies to support the base, thus obtaining a base with an elastic body;

[0081] forming:

[0082] S3, placing the base with the elastic body at the required construction site, and wrapping the elastic body with a prefabricated foam fence;

[0083] S4, placing the track plate on the prefabricated foam fence, at which point an adhesive layer perfusion cavity is formed between the prefabricated foam fence, the track plate and the elastomer;

[0084] S5. Pour the three components of adhesive into the mixing barrel according to the proportion of the mixing ratio, stir them thoroughly to make them evenly mixed, the stirring time is 3-5 minutes, use mechanical method to stir, the electric stirrer stirs thoroughly up and down, left and right, the speed should be 300-2000 rpm, after the mixture is stirred, let it stand for 1 minute, and then divide the stirred mixture into the filling container;

[0085] S6. At 5℃-35℃, pour the adhesive into the adhesive layer through the pouring hole on the track plate, until the entire adhesive layer is filled. After the pouring is completed, close the pouring hole and wait for curing. The curing time is 12-48 hours.

[0086] S7. Remove the prefabricated foam fence and complete the production of the shock-absorbing ballastless track slab at the construction site.

[0087] Furthermore, the height of the elastic body is 30MM, and the height of the adhesive layer is 10MM.

[0088] Furthermore, the adhesive layer is a three-component adhesive.

[0089] Further, the elastomer comprises the following components in parts by weight:

[0090] Polyamide thermoplastic elastomer 200 parts

[0091] 100 parts of nitrile rubber

[0092] 5 parts paraffin

[0093] 35 parts of semi-reinforced carbon black

[0094] 4 parts of dicumyl peroxide

[0095] 4 parts of antioxidant

[0096] 1.5 parts of isonicotinamide

[0097] 4 parts of 2,6-difluoro-4-bromoiodobenzene.

[0098] The specific steps are as follows:

[0099] S1, heating the above-mentioned parts by weight of the polyamide thermoplastic elastomer and the nitrile rubber to 130-135° C., dehydrating under vacuum, adding the above-mentioned parts by weight of isonicotinamide and 2,6-difluoro-4-bromoiodobenzene, continuing to stir and heating to 140-145° C.;

[0100] S2. Add the above-mentioned weight parts of paraffin wax, semi-reinforcing carbon black, diisopropylbenzene peroxide and antioxidant to the mixture of S1, pour into a mold, heat to 160-165° C. and continue mixing and stirring for 2-4 hours to obtain the elastomeric material.

[0101] Further, the adhesive comprises the following components in parts by weight:

[0102] Component A

[0103] Isocyanate 22 parts

[0104] 32 parts of polyether polyol

[0105] Component B

[0106] Polyol 7 parts

[0107] Chain extender 6 parts

[0108] 1.2 parts of anti-aging agent

[0109] 1.1 parts of UV protection agent

[0110] Color paste 0.6 parts

[0111] Boron carbide powder 1.3 parts

[0112] Component C

[0113] 1.8 parts of magnesium hydroxide whisker

[0114] 2.2 parts of Al2O3-Y2O3 whiskers.

[0115] Further, the preparation method of Al2O3-Y2O3 whiskers is:

[0116] Aluminum nitrate is dissolved in distilled water to prepare a solution with a concentration of 0.5-2.0 mol / L; urea in an amount of 2-10 times the molar amount of aluminum nitrate is added to the aluminum nitrate solution, and stirred evenly at room temperature to obtain a transparent and clear sol; the prepared sol is then placed in a reaction kettle, and maintained at 90-120° C. for 6-12 hours to obtain a white precipitate of an aluminum oxide whisker precursor; the white precipitate is then washed with distilled water, and then calcined at 1100-1300° C. for 2-12 hours to obtain an aluminum oxide whisker;

[0117] Alumina whiskers are added to an aqueous solution of polyvinyl alcohol to prepare a suspension with a solid content of 20wt%, an aqueous solution of yttrium nitrate hexahydrate is added to the suspension to obtain a mixed solution, the pH of the mixed solution is adjusted to 8, yttrium hydroxide is deposited on the surface of the alumina whiskers to form a precipitate, the precipitate is filtered, cleaned and then calcined to obtain Al2O3-Y2O3 whiskers.

[0118] Furthermore, the calcination temperature is 1350-1400° C., and the calcination time is 2-4 hours.

[0119] Furthermore, a weakly alkaline substance is selected to adjust the pH of the mixed solution, which may be aqueous ammonia, sodium carbonate or sodium bicarbonate.

[0120] Furthermore, the polyether polyol is polytetrahydrofuran or polyethylene oxide or polypropylene oxide polyol.

[0121] Working conditions:

[0122] 1. It is strictly forbidden to carry out base treatment construction on the base surface with visible water or damp surface. The moisture content of concrete surface should be less than 30%.

[0123] 2. After installing the buffer elastomer and fence, the injection system should be kept dry and no water should enter.

[0124] 3. Construction can only be carried out when the daily average temperature ranges from 5℃ to 35℃.

[0125] V. Technical quality requirements:

[0126] 1. Ensure that the surface of the base plate is flat, completely dry, clean, frost-free and dirt-free.

[0127] 2. When installing the buffer elastomer, ensure that the bottom surface of the elastomer is completely bonded and tightly to the base of the track plate, without any hollows or warping.

[0128] 3. When pouring, pour the three-component adhesive into the mixing barrel according to the required proportion of the mix ratio, stir thoroughly to make it mix evenly, the stirring time is 3-5 minutes, no water should be present during stirring, mechanical stirring must be adopted, electric mixer should stir thoroughly up and down, left and right, the speed should be 300-2000 rpm, to prevent too many bubbles from being introduced, the mixed liquid should be left to stand for 1 minute after stirring, and then the stirred mixed liquid should be divided into the pouring container for pouring, and no spillage should be done during division and pouring.

[0129] 4. After the pouring is completed, the construction tools should be cleaned with a special cleaning fluid.

[0130] Note:

[0131] 1. Construction on a damp or wet surface will cause foaming or bulging.

[0132] 2. If the three components are not operated in proportion, the phenomenon of non-solidification, cold flow phenomenon (the state of this phenomenon is solidification first and then dissolution) or hardening of the colloid will occur.

[0133] 3. If the three components are not stirred evenly, non-solidification or cold flow will also occur.

[0134] 4. Do not use electric fans or similar tools to shorten the drying time.

[0135] 6. Quality requirements:

[0136] 1. Check the flatness of the base surface. Only gentle changes in level are allowed, with a deviation of ±20.5mm.

[0137] 2. Before dropping the plate, check the bonding condition between the buffer elastomer and the track plate base. No loose conditions such as hollowing, warping, etc. are allowed.

[0138] 3. Before pouring, make sure there is no moisture in the cavity.

[0139] 4. On-site inspection by the construction unit:

[0140] 4.1 On-site visual inspection: After pouring and curing, cut off the overflowed materials in some parts. The formed bonding layer should be tightly bonded with the concrete and the buffer cushion layer, with a smooth surface, no bulging, no missing coating, no bubbles, no cracks, no hollows, no foreign matter mixed in or separation.

[0141] 4.2 Thickness detection: Use a probe to check the thickness, and check 5 locations for every 50 seams.

[0142] 2. Material requirements:

[0143] 1. To prevent the product quality from being affected by the environment and climate, it must be placed on wooden racks and stored in appropriate places. The ideal storage place for the product is a ventilated and dry room. It cannot be piled in the open air. The storage temperature should be kept at a low temperature.

[0144] It should not exceed 50℃ and should not be affected by climate or operating operations.

[0145] 2. During storage, the product should be kept away from direct sunlight, rain and snow, and should be kept sealed and intact. It should not come into contact with acids, alkalis, oils, organic solvents and other materials that may affect product quality, and should be kept at least 1m away from heat sources.

[0146] 3. When using liquid materials, if the entire barrel of material cannot be used up at one time, the barrel lid must be tightly closed immediately after each use to prevent water vapor and impurities from entering the barrel and affecting the quality.

[0147] 4. If more than two grades of A (B) materials are used, they should be stacked according to the grades and clearly marked.

[0148] The measured vibration reduction effect shows that compared with the non-vibration reduction structure, the vibration reduction effect of the vibration reduction structure on the foundation is greater than 20dB in acceleration level, and the root mean square difference of vibration acceleration from 1 to 200Hz is greater than 17 dB, which fully meets the design requirements.

[0149] Polyurethane material is selected as the prefabricated elastic layer of the track slab. The track slab and the offline foundation are in "flexible" contact. The performance indicators of the supporting layer are adjusted to meet the vibration reduction needs of different sections. Using a special process, the prefabricated layer is compounded on the bottom of the track slab, and it comes with a field pouring fence or pouring bag, which is shipped together with the track slab. The cast-in-place layer mainly has the function of filling and adjustment, and the same material is used in different vibration reduction sections. In non-vibration reduction sections, the stiffness of the supporting layer is 1MPa / mm. When the vibration reduction effect is greater than 10dB, the stiffness of the supporting layer is 0.5MPa / mm, 0.3MPa / mm and 0.1MPa / mm as the intermediate transition section.

[0150]

[0151] As shown in the above chart, it is planned to use the prefabricated TGTD + cast-in-place filling layer method for the first time to pave the shock-absorbing road section and transition section, which effectively controls the quality stability of the product and reduces the difficulty of on-site construction. The experiment shows that the vertical displacement hysteresis curve under dynamic cyclic load shows that the supporting layer has good elastic recovery ability and good followability.

[0152]

[0153] As shown in the above diagram, using special equipment to pour the filling layer on the non-vibration-absorbing section can achieve rapid and accurate positioning of the track plate, reaching a construction speed of 200m / day to 250m / day for a single working surface. Experiments show that under the action of 1.5 times the static axle load, the vertical displacement of the non-vibration-absorbing plate is 0.36mm. 3 million vertical and lateral fatigue tests on the track structure show that there is no obvious difference in the mechanical properties and deformation of the track structure before and after fatigue.

[0154] The elastomer includes the following components in parts by weight:

[0155] Polyamide thermoplastic elastomer 200 parts

[0156] 100 parts of nitrile rubber

[0157] 5 parts paraffin

[0158] 35 parts of semi-reinforced carbon black

[0159] 4 parts of dicumyl peroxide

[0160] 4 parts of antioxidant

[0161] 1.5 parts of isonicotinamide

[0162] 4 parts of 2,6-difluoro-4-bromoiodobenzene.

[0163] The preparation method of the polyamide thermoplastic elastomer is as follows: firstly, acylation reaction is carried out between succinic acid and polyetheramine D400 to obtain a succinic acid extended polyetheramine soft segment; then, the succinic acid extended polyetheramine soft segment is subjected to a ring-opening polymerization reaction with lactam and a ring-opening agent to obtain a polyamide 6 prepolymer and a thermoplastic elastomer prepolymer, and then the two are subjected to an amide exchange reaction, and finally, the cast strip is drawn, pelletized, and dried to obtain the polyamide thermoplastic elastomer. The number average molecular weight of the succinic acid extended polyetheramine soft segment is 3000-4000. The temperature of the ring-opening polymerization reaction is 250°C, the pressure of the ring-opening polymerization reaction is 0.25MPa, and the time of the ring-opening polymerization reaction is 4h.

[0164] The antioxidant is a mixture of styrenated phenol and dioctyl phthalate in a mass ratio of 50:33.

[0165] The particle size of the semi-reinforcing carbon black is 80 nm.

[0166] A method for preparing an elastomeric material comprises the following steps:

[0167] S1, heating the above-mentioned parts by weight of the polyamide thermoplastic elastomer and the nitrile rubber to 130° C., dehydrating under vacuum, adding the above-mentioned parts by weight of isonicotinamide and 2,6-difluoro-4-bromoiodobenzene, continuing to stir and heating to 140° C.;

[0168] S2. Add the above-mentioned weight parts of paraffin wax, semi-reinforcing carbon black, diisopropylbenzene peroxide and antioxidant to the mixture of S1, pour into a mold, heat to 160° C. and continue mixing and stirring for 2 hours to obtain the elastomeric material.

[0169] The total time for the S1 and S2 operation steps was 4 h.

[0170] <Comparative Example 1>

[0171] Commercially available elastomeric materials.

[0172] <Comparative Example 2>

[0173] No isonicotinamide and 2,6-difluoro-4-bromoiodobenzene were added, and the remaining components and preparation method were the same as those in Example 3.

[0174] <Detection Experiment>

[0175] The physical test data of the elastomeric material prepared by this method, corresponding to each embodiment and comparative example, are shown in the following Table 1:

[0176] Table 1

[0177]

[0178] The test data comparison of the substance content, water impermeability and color appearance of the elastomeric material prepared by this method, corresponding to each embodiment and comparative example, is shown in the following Table 2:

[0179] Table 2

[0180]

[0181] The tensile modulus, tensile strength and retention rate test data of the elastomeric material prepared by this method, corresponding to each embodiment and comparative example, are compared as shown in Table 3 below:

[0182] Table 3

[0183]

[0184] As can be seen from Table 3, the tensile elastic modulus of the elastomeric material in Examples 1-3 is significantly better than that in Comparative Examples 1 and 2, indicating that it has a good elastic recovery rate, which is significantly better than the tensile elastic modulus industry standards of (23±2°C) 0.3MPa and (-30±2°C) 0.6MP. The tensile strength of Examples 1-3 is also significantly better than that of Comparative Examples 1 and 2, and the tensile strength is high, which is significantly better than the tensile strength industry standard of 3MPa.

[0185] Adhesive preparation method:

[0186] The composition comprises the following components in parts by weight:

[0187] Component A

[0188] Isocyanate 22 parts

[0189] 32 parts of polyether polyol

[0190] Component B

[0191] Polyol 7 parts

[0192] Chain extender 6 parts

[0193] 1.2 parts of anti-aging agent

[0194] 1.1 parts of UV protection agent

[0195] Color paste 0.6 parts

[0196] Boron carbide powder 1.3 parts

[0197] Component C

[0198] 1.8 parts of magnesium hydroxide whisker

[0199] 2.2 parts of Al2O3-Y2O3 whiskers.

[0200] Wherein, the preparation method of Al2O3-Y2O3 whisker is:

[0201] Aluminum nitrate is dissolved in distilled water to prepare a solution with a concentration of 1.2 mol / L; urea in an amount of 5 times the molar amount of aluminum nitrate is added to the aluminum nitrate solution, and stirred evenly at room temperature to obtain a transparent and clear sol; the prepared sol is then placed in a reaction kettle and maintained at 100°C for 8 hours to obtain a white precipitate of an aluminum oxide whisker precursor; the white precipitate is then washed with distilled water and calcined at 1200°C for 6 hours to obtain an aluminum oxide whisker;

[0202] Alumina whiskers are added to an aqueous solution of polyvinyl alcohol to prepare a suspension with a solid content of 20wt%, an aqueous solution of yttrium nitrate hexahydrate is added to the suspension to obtain a mixed solution, the pH of the mixed solution is adjusted to 8, yttrium hydroxide is deposited on the surface of the alumina whiskers to form a precipitate, the precipitate is filtered, cleaned and then calcined to obtain Al2O3-Y2O3 whiskers.

[0203] The calcination temperature is 1350°C and the calcination time is 3h.

[0204] Ammonia water is used to adjust the pH of the mixed solution.

[0205] The polyether polyol is polyoxypropylene polyol.

[0206] The isocyanate is meta-toluene diisocyanate.

[0207] The polyol is 1,2-propylene glycol.

[0208] <Detection Experiment>

[0209] The comprehensive performance test of the sealing material prepared by this method. The test data corresponding to each embodiment and the comparative example are compared as shown in the following table:

[0210]

[0211]

[0212] The sealing material of the present invention has low density, high bonding strength, good durability, wide applicable substrates, environmental protection and no pollution, and has excellent wear resistance and excellent resilience. Magnesium hydroxide whiskers and Al2O3-Y2O3 whiskers are added to the components as special thixotropic agents, which play a good synergistic effect. Magnesium hydroxide whiskers are particularly suitable for humid environments, and strong hydrogen bonds will be formed during contact with water, effectively enhancing adhesion and resilience. The addition of Al2O3-Y2O3 whiskers also effectively enhances the durability of the sealing material.

Claims

1. A method for preparing a vibration-absorbing ballastless track slab, characterized in that: It includes a track plate, an adhesive layer, an elastic body, an adhesive layer and a base arranged in sequence from top to bottom; The preparation method is as follows: S1. Clean the bottom surface of the track plate and the base surface to make them dry, clean, and free of dust, debris or residual chemical materials; S2, bonding the elastic body to the surface of the base, wherein each base needs to be equipped with two elastic bodies to support the base; S3, wrapping the elastomer with a prefabricated foam fence; S4, placing the track plate on the prefabricated foam fence, at which point an adhesive layer perfusion cavity is formed between the prefabricated foam fence, the track plate and the elastomer; S5. Pour the three components of adhesive into the mixing barrel according to the proportion of the mixing ratio, stir them thoroughly to make them evenly mixed, the stirring time is 3-5 minutes, use mechanical method to stir, the electric stirrer stirs thoroughly up and down, left and right, the speed should be 300-2000 rpm, after the mixture is stirred, let it stand for 1 minute, and then divide the stirred mixture into the filling container; S6. At 5℃-35℃, pour the adhesive into the adhesive layer through the pouring hole on the track plate, until the entire adhesive layer is filled. After the pouring is completed, close the pouring hole and wait for curing. The curing time is 12-48 hours. S7. Remove the prefabricated foam fence, and the production of the shock-absorbing ballastless track slab is completed; The elastomer includes the following components in parts by weight: Polyamide thermoplastic elastomer 200 parts 100 parts of nitrile rubber 5 parts paraffin 35 parts of semi-reinforced carbon black 4 parts of dicumyl peroxide 4 parts of antioxidant 1.5 parts of isonicotinamide 4 parts of 2,6-difluoro-4-bromoiodobenzene The specific steps are as follows: S1, heating the above-mentioned parts by weight of the polyamide thermoplastic elastomer and the nitrile rubber to 130-135° C., dehydrating under vacuum, adding the above-mentioned parts by weight of isonicotinamide and 2,6-difluoro-4-bromoiodobenzene, continuing to stir and heating to 140-145° C.; S2. Add the above-mentioned weight parts of paraffin wax, semi-reinforcing carbon black, diisopropylbenzene peroxide and antioxidant to the mixture of S1, pour into a mold, heat to 160-165° C. and continue mixing and stirring for 2-4 hours to obtain the elastomeric material.

2. The method for preparing a vibration-absorbing ballastless track slab according to claim 1, characterized in that: The height of the elastic body is 30mm and the height of the adhesive layer is 10mm.

3. The method for preparing a vibration-absorbing ballastless track slab according to claim 1, characterized in that: The adhesive layer is a three-component adhesive.

4. The method for preparing a vibration-absorbing ballastless track slab according to claim 1, characterized in that: The adhesive comprises the following components in parts by weight: Component A Isocyanate 22 parts 32 parts of polyether polyol Component B Polyol 7 parts Chain extender 6 parts 1.2 parts of anti-aging agent 1.1 parts of UV protection agent Color paste 0.6 parts Boron carbide powder 1.3 parts Component C 1.8 parts of magnesium hydroxide whisker 2.2 parts of Al2O3-Y2O3 whiskers.

5. The method for preparing a vibration-absorbing ballastless track slab according to claim 4, characterized in that: The preparation method of Al2O3-Y2O3 whiskers is as follows: Aluminum nitrate is dissolved in distilled water to prepare a solution with a concentration of 0.5-2.0 mol / L; urea in an amount of 2-10 times the molar amount of aluminum nitrate is added to the aluminum nitrate solution, and stirred evenly at room temperature to obtain a transparent and clear sol; the prepared sol is then placed in a reaction kettle, and maintained at 90-120° C. for 6-12 hours to obtain a white precipitate of an aluminum oxide whisker precursor; the white precipitate is then washed with distilled water, and then calcined at 1100-1300° C. for 2-12 hours to obtain an aluminum oxide whisker; Alumina whiskers are added to an aqueous solution of polyvinyl alcohol to prepare a suspension with a solid content of 20wt%, an aqueous solution of yttrium nitrate hexahydrate is added to the suspension to obtain a mixed solution, the pH of the mixed solution is adjusted to 8, yttrium hydroxide is deposited on the surface of the alumina whiskers to form a precipitate, the precipitate is filtered, cleaned and then calcined to obtain Al2O3-Y2O3 whiskers.

6. The method for preparing a vibration-absorbing ballastless track slab according to claim 5, characterized in that: The calcination temperature is 1350-1400°C and the calcination time is 2-4h.

7. The method for preparing a vibration-absorbing ballastless track slab according to claim 5, characterized in that: A weakly alkaline substance is selected to adjust the pH of the mixed solution, which may be aqueous ammonia, sodium carbonate or sodium bicarbonate.

8. The method for preparing a vibration-absorbing ballastless track slab according to claim 4, characterized in that: The polyether polyol is polytetrahydrofuran or polyethylene oxide or polypropylene oxide polyol.

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