CN106758570A - Carbon nanotube modified heightening damping vibration attenuation mute steel rail - Google Patents

Abstract

The raised damping and vibration-reducing silent rail includes a rail base, a damping unit, and a damping layer I. The damping unit includes a damping layer A and a cushion layer. The cushion layer is located on the side close to the damping layer I. The damping layer A is located at The side close to the base of the rail. The thickness ratio of the cushion layer to the damping layer A is 4-16; the thickness ratio of the cushion layer to the damping layer I is 4-16. The cushion layer is carbon nanotube modified polyurethane foam. Several hollow grooves are uniformly distributed in the carbon nanotube modified polyurethane foam. The present invention adopts the carbon nanotube modified hollow groove foam as the cushion layer, which not only makes the cushion layer and the original damping structure jointly form a cushion damping structure, but also can increase the shear strength of the cushion layer (considering from the perspective of vibration reduction that the cushion layer is required to The shear strength should be as large as possible), improve the fire performance of the bedding layer, increase the damping effect of the bedding layer itself, and make up for the low strength of the bedding layer caused by more hollow grooves.

Description

Carbon nanotube modified pad height damping vibration reduction silent rail

technical field

The invention belongs to the field of construction, and relates to a vibration-damping and silent steel rail, in particular to a carbon nanotube-modified pad height damping and vibration-damping silent steel rail.

Background technique

In today's society, all kinds of vibrations and noises emerge in endlessly and cannot be avoided. However, the long-term effect of this environment not only affects people's physical and mental health, but also leads to fatigue damage of structural equipment due to long-term vibration, and a decrease in the sensitivity of precision instruments. Therefore, controlling vibration and reducing noise has become an urgent problem to be solved.

In recent years, with the widespread use of damping materials in the field of engineering vibration reduction, damping rails have also begun to receive widespread attention. The main forms of existing damping rails include the following three types: (1) a layer of damping layer is pasted on the side of the rail to form a free damping structure; (2) a constrained layer is wrapped outside the damping layer to form a constrained damping structure; (3) ) adding a special-shaped labyrinth structure in the damping layer to form a labyrinth constrained damping; (4) adding a magnetic material layer/magnetic adsorption layer to the constrained damping structure, and using one or more damping layers. Among them, the free damping structure mainly relies on the tension and compression deformation of the damping layer to dissipate energy. The constrained damping structure mainly relies on the shear deformation of the damping layer to dissipate energy, and the damping layer also produces tension and compression deformation, thereby dissipating more energy. The energy dissipation principle of the labyrinth constrained damping is roughly the same as that of the constrained damping structure; the purpose of adding the labyrinth structure is to increase the shear deformation. For the damping structure in which a magnetic material layer is added to the constrained damping structure, the energy dissipation mechanism is exactly the same as that of the constrained damping structure; the added magnetic material layer is to absorb vibration through the magnetic material itself and increase the structural integrity. However, the above four structures all have the situation that the inner half-layer damping does not contribute much to energy consumption, which reduces the efficiency of the damping layer in reducing vibration and energy consumption, resulting in waste of damping materials and increasing costs. In addition, the manufacturing process of the labyrinth constrained damping structure is too complicated, which is not conducive to product promotion. The constrained damping structure with the addition of a magnetic material layer is essentially the same as the original constrained damping structure. The newly added magnetic material layer is not only difficult to provide a better vibration reduction and energy dissipation effect than the damping material, but also cannot increase the sound absorption effect, and Will increase the structural quality. For the damping layer using the spraying process, since there is no problem of interlayer bonding force, there is no need for magnetic materials to increase the integrity.

Chang Guan et al. ("Viscoelastic Damping Materials", National Defense Industry Press, 2012, p. 230) showed that a layer firmly bonded between the damping layer and the substrate has a very high shear stiffness and a very high bending stiffness. A small material as an intermediate layer (Spacer) can increase the structural loss factor and reduce the quality of the system. They argue that in a damping structure of a given thickness, two-thirds of the damping occurs in the outer half-layer material, so that the inner half-layer can be replaced with a "weightless" material. The "weightless" material of the inner half layer is called the expansion layer or the pad layer, which can increase the damping treatment distance from the bonded midline plane (equivalent to increasing the thickness of the damping layer), thus increasing the thickness of the damping layer. The tension and compression deformation of the viscoelastic layer is reduced, and the structural damping increases accordingly. At the same time, the addition of the expansion layer also has the effect of widening the effective damping temperature width. And because the material density of the expansion layer is very small, the apparent quality of the damping material system can be significantly reduced. The cushion layer currently used is honeycomb or fluffy hard foam, and its incidental functions are sound absorption and heat insulation. However, since the existing padding damping structure is often bonded with cured damping materials through adhesives, it is easy to cause problems such as weak interlayer bonding and low strength of the expansion layer; when the padding damping structure is applied to larger This problem is especially obvious when the vibration of the vibrating member is damped. In addition, the use of ordinary hard foam is not fire-resistant, and there are also problems such as the rails are not fire-proof, and the safety cannot be guaranteed.

At present, based on the research enthusiasm of carbon nanotubes, many people have conducted research on adding carbon nanotubes to foam. Among them, the method of physical addition is mostly used. Kuan HC and Jung Y C et al. used chemical bonding to add carbon nanotubes to polyurethane foam. However, the purpose of adding carbon nanotubes is to increase the strength and toughness of the material, as well as to improve the conductivity, electromagnetic shielding and photoelectron emission of the material. Based on the above purpose, the current application of polyurethane foam with added carbon nanotubes is limited to the following areas: electronic materials, smart materials, energy-saving materials and biomedical materials.

Contents of the invention

Aiming at the problems existing in the existing high-damping damping and vibration-reducing mute rails, the carbon nanotube modified cushioning high-damping and vibration-damping silent rails of the present invention use carbon nanotube-modified hollow groove foam, which not only increases the resistance of the cushion layer It not only improves the shear strength and damping effect, but also improves the fire performance of the cushion layer, and improves the problem of low strength of the cushion layer caused by the hollow groove.

The technical solution of the present invention: padding the damping and damping silent rail, including the rail base layer, the damping unit and the damping layer I, the damping unit including the damping layer A and the cushioning layer, the cushioning layer is located on the side close to the damping layer I, The damping layer A is located on the side close to the base layer of the rail. The thickness ratio of the cushion layer to the damping layer A is 4-16; the thickness ratio of the cushion layer to the damping layer I is 4-16. The cushion layer is carbon nanotube modified polyurethane foam.

The preparation of the carbon nanotube-modified polyurethane foam comprises the following steps: (1) modifying the carbon nanotubes to obtain hydroxylated carbon nanotubes; (2) adding the hydroxylated carbon nanotubes obtained in step (1) to into the B component used to prepare the cushion layer foam, that is, the hydroxyl compound; (3) mix the B component mixed with hydroxylated carbon nanotubes and the A component isocyanate at a temperature of 60-80°C and a temperature of 15-18MPa Reacting under pressure conditions, the carbon nanotube modified polyurethane foam can be obtained. Wherein, several hollow grooves are evenly distributed in the carbon nanotube modified polyurethane foam, and the interval between the adjacent hollow grooves is not less than 4-6mm; the hole diameter of the hollow grooves is 4-6mm. Compared with the existing hard foam material cushion layer, the carbon nanotube modified hollow groove cushion layer has higher shear strength, which is more conducive to the energy dissipation of the damping layer, so the vibration damping performance can be improved.

Wherein, the side of the damping layer I away from the damping unit is further provided with a constrained layer, and the constrained layer is a steel plate; the number of the damping units is 1-3.

Wherein, a corundum layer inlaid on the surface of each damping unit is provided between the pad layer and the damping layer A, the quantity of the corundum is 0.5-1.5kg/m ² , and the particle size of the corundum is 1.6 -2.0mm.

The preparation of hydroxylated carbon nanotubes is mainly divided into two steps:

1. The carbon nanotubes were modified by the mixed acid method, and the single-walled carbon nanotubes (SWCNTs) were treated with a 3:1 mixed solution of 40ml concentrated sulfuric acid and nitric acid, and then the mixture was ultrasonically treated at 40°C for 3 Hour. Carboxyl groups can be introduced on the surface of carbon nanotubes.

2. Disperse 20 mg of the carboxylated single-walled carbon nanotubes obtained in the first step in anhydrous tetrahydrofuran and perform ultrasonic treatment for 30 minutes. Then 2 mg of lithium aluminum hydride were added and sonicated for 1 hour. The resulting reaction mixture was slowly added to 200 ml of methanol and filtered with polycarbonate filter paper. The resulting product was then dried in a vacuum oven at 80°C for 3 hours. Hydroxylated carbon nanotubes can be obtained.

The preparation method of the free height damping and vibration reduction mute rail comprises the following steps: (1) spraying the damping material on the side of the rail base to obtain the damping layer A, and then performing sandblasting; (2) pouring on the damping layer A after the treatment as The carbon nanotube modified polyurethane foam of the cushion layer; (3) continue to spray the damping material on the carbon nanotube modified polyurethane foam to obtain the damping layer I; the free cushion height damping and vibration reduction in the cushion height damping and vibration reduction mute rail can be obtained Silent rails. The thickness of the damping layer A is 3-5mm, the thickness of the cushion layer is 18-22mm, and the thickness of the damping layer I is 3-5mm. The damping layer adopts the construction method of direct spraying, which has good product integrity, simple process, low cost and convenient engineering application.

The preparation method of the restrained height damping and vibration-reducing mute rail comprises the following steps: (1) spraying damping material on the side of the rail base to obtain a damping layer A, and then performing sandblasting treatment; (2) pouring on the damping layer A after treatment as The carbon nanotube modified polyurethane foam of the upper layer; (3) continue to spray the damping material on the carbon nanotube modified polyurethane foam to obtain the damping layer I; (4) wrap the steel plate with a thickness of 1-3mm on the damping layer I as a constraint layer, the restrained heightened damping vibration damping silent rail in the padding damping vibration reducing silent rail can be obtained. The free height damping vibration damping silent steel rail in the cushioning height damping vibration damping silent steel rail can be obtained. The thickness of the damping layer A is 1-3mm, the thickness of the cushion layer is 14-16mm, and the thickness of the damping layer I is 1-3mm.

The preparation method of the multi-layer constrained pad height damping and vibration-reducing silent rail comprises the following steps: (1) spraying damping material on the side of the rail base layer to obtain a damping layer A, and then performing sandblasting treatment; Pouring the carbon nanotube modified polyurethane foam as the cushion layer; (2a) continue spraying damping material on the carbon nanotube modified polyurethane foam of the outermost damping unit, and sandblasting; pouring the carbon nanotube modified polyurethane foam as the cushion layer permanent polyurethane foam; repeat step (2a), until the number of damping units reaches the requirements; (3) continue to spray damping material on the carbon nanotube modified polyurethane foam to obtain damping layer I; (4) wrap thickness in damping layer I A steel plate with a diameter of 1-3mm is used as the constraining layer to obtain a multi-layer constrained cushioning, damping, vibration-reducing and silent rail in the raised-damping, vibration-reducing, and silent rail. The thickness of the damping layer A is 1-3mm, the thickness of the cushion layer is 14-16mm, and the thickness of the damping layer I is 1-3mm.

The specific steps of the sandblasting treatment are as follows: the spraying timing is 8-10 seconds after the damping material is sprayed; the sandblasting air pressure is 0.6-0.8 MPa, the sandblasting distance is 1 meter, and the temperature is 15-25 degrees Celsius. When the above parameters are used for sandblasting, the gravel is embedded in half of the adjacent two layers, and the effect of vibration and noise reduction is the best.

In order to verify that the raised damping and vibration-reducing silent steel rail of the present invention has excellent vibration-reducing performance, the present invention adopts the following method to carry out a vibration test on the raised damping and vibration-reducing silent steel rail of the present invention and a blank steel plate. A 500mm×43mm×3.5mm steel plate is used as a base material (equivalent to a steel rail) to make a raised damping, vibration-reduction and quiet floor. The structural parameters of the raised damping, vibration-reduction and quiet floor are detailed in Examples 1-9. Among them, the polyurethane foam layer with a density of 200kg/ ^m3 is used as the cushion layer; the polyurethane viscoelastic damping material provided by the Institute of Functional Materials of Qingdao Technological University is used as the damping layer. A 500mm×43mm×3.5mm steel plate was used as a blank sample for comparison.

The DASP intelligent data acquisition and signal analysis system V10 of Beijing Oriental Institute of Vibration and Noise Technology is used for data acquisition and analysis. The test method adopts the hammer excitation method to simulate the process of free attenuation of vibration after the sample is excited. In order to reduce the influence of external support on the free attenuation of vibration, the pattern is hoisted horizontally with a thin fishing line. The lifting point is 50mm from the left and right sides of the steel plate; the vibration pickup point and the excitation point are respectively 25mm from the left and right sides of the steel plate. As shown in Figure 4; the sampling frequency is 2048Hz, the excitation head is a steel head, and the excitation force is 45N.

Beneficial effects of the present invention:

1. Compared with the prior art, the present invention adopts the carbon nanotube modified hollow groove foam as the pad layer, which not only makes the pad layer and the original damping structure jointly form a pad height damping structure, but also can increase the shear strength of the pad layer ( From the perspective of vibration reduction, it is required that the shear strength of the cushion layer be as large as possible), improve the fire performance of the cushion layer, increase the damping effect of the cushion layer itself, and make up for the low strength of the cushion layer caused by more hollow grooves .

2. In the present invention, the sandblasting treatment is performed between the damping layer and the cushion layer, which can make the interlayer bond more firm, and can also increase the contact area between the damping material and the cushion layer so as to improve the damping and vibration reduction effect.

3. Compared with the cushion layer of hard foam material, the carbon nanotube modified hollow groove cushion layer has very good flame retardancy. As a component of the silent steel rail used in the subway tunnel, it can effectively prevent fire and provide better safety Assure.

4. The present invention sets a damping layer A between the rail base layer and the damping unit, on the one hand, it increases the firmness of the padding layer; on the other hand, it ensures that the rail is a padding damping structure no matter whether the vibration propagates from the inside to the outside or from the outside to the inside .

Description of drawings

Fig. 1 is the structural representation of cushion layer described in the present invention;

Fig. 2 free height damping and vibration reduction silent steel rail of the present invention;

Fig. 3 Constraint pad height damping damping silent steel rail of the present invention;

Fig. 4 multi-layer constraining pad height damping damping silent steel rail of the present invention;

Fig. 5 is the structural representation of the hammer vibration excitation test device of the present invention;

Among them, 1 is foam, 2 is hollow groove, 3 is rail, 4 is damping layer I, 5 is damping layer A, and 6 is constraining layer.

detailed description

Below in conjunction with embodiment the present invention will be further described.

Embodiment 1: free height damping and vibration reduction silent steel rail

The free cushioning damping and vibration-reducing mute rail includes a rail base, a damping unit and a damping layer I, and the damping unit includes a damping layer A and a cushion layer, the cushion layer is located on the side close to the damping layer I, and the damping layer A Located on the side close to the base of the rail. The cushion layer is carbon nanotube modified polyurethane foam. The thickness of the damping layer A is 5mm, the thickness of the cushion layer is 20mm, and the thickness of the damping layer I is 5mm. Wherein, a corundum layer inlaid on the surfaces of the cushion layer and the damping layer A is provided, the quantity of the corundum is 4.0kg/m ² , and the particle size of the corundum is 1.6mm.

The preparation of the carbon nanotube modified polyurethane foam comprises the following steps:

(1) modify the carbon nanotubes to obtain hydroxylated carbon nanotubes; the detailed steps are: (1a) adopt the mixed acid method to modify the carbon nanotubes, and use 40ml concentrated sulfuric acid to single-wall carbon nanotubes (SWCNTs) and nitric acid in a 3:1 mixture, and then the mixture was sonicated at 40°C for 3 hours. Carboxyl groups can be introduced on the surface of carbon nanotubes. (1b) Disperse 20 mg of the carboxylated single-walled carbon nanotubes obtained in the first step in anhydrous tetrahydrofuran and perform ultrasonic treatment for 30 minutes. Then 2 mg of lithium aluminum hydride were added and sonicated for 1 hour. The resulting reaction mixture was slowly added to 200 ml of methanol and filtered with polycarbonate filter paper. The resulting product was then dried in a vacuum oven at 80°C for 3 hours. Hydroxylated carbon nanotubes can be obtained.

(2) The hydroxylated carbon nanotubes obtained in step (1) are added to the B component for preparing the cushion layer foam, that is, the hydroxyl compound;

(3) React component B mixed with hydroxylated carbon nanotubes and component A isocyanate at a temperature of 70° C. and a pressure of 18 MPa to obtain carbon nanotube-modified polyurethane foam. Wherein, several hollow grooves are uniformly distributed in the carbon nanotube modified polyurethane foam, and the interval between the adjacent hollow grooves is not less than 4mm; the hole diameter of the hollow grooves is 4mm. Compared with the existing hard foam material cushion layer, the carbon nanotube modified hollow groove cushion layer has higher shear strength, which is more conducive to the energy dissipation of the damping layer, so the vibration damping performance can be improved.

The preparation method of the free height damping and vibration reduction mute rail comprises the following steps: (1) spraying the damping material on the side of the rail base to obtain the damping layer A, and then performing sandblasting; (2) pouring on the damping layer A after the treatment as The carbon nanotube modified polyurethane foam of the cushion layer; (3) continue to spray the damping material on the carbon nanotube modified polyurethane foam to obtain the damping layer I, which can obtain the free cushion height damping and vibration reduction in the cushion height damping and vibration reduction mute rail Silent rails. The damping layer adopts the construction method of direct spraying, which has good product integrity, simple process, low cost and convenient engineering application. The specific steps of the sandblasting treatment are as follows: the spraying timing is 10 seconds after the damping material is sprayed; the sandblasting air pressure is 0.6Mpa, the sandblasting distance is 1m, and the temperature is 20°C. When the above parameters are used for sandblasting, the gravel is embedded in half of the adjacent two layers, and the effect of vibration and noise reduction is the best.

In order to verify the excellent damping performance of the raised damping, vibration-absorbing and silent steel rail of the present invention, the following method was used to carry out a vibration test on the raised damping, vibration-reducing and quiet floor and the blank steel plate prepared by the above method.

Test method: A 500mm×43mm×3.5mm steel plate is used as the floor substrate to prepare a raised damping and vibration-reducing mute floor pattern, and the steel plate is used as a blank steel plate. The DASP intelligent data acquisition and signal analysis system V10 of Beijing Oriental Institute of Vibration and Noise Technology is used for data acquisition and analysis. The test method adopts the hammer excitation method to simulate the process of free attenuation of vibration after the sample is excited. In order to reduce the influence of external support on the free attenuation of vibration, the pattern is hoisted horizontally with a thin fishing line. The lifting point is 50mm from the left and right sides of the steel plate; the vibration pickup point and the excitation point are respectively 25mm from the left and right sides of the steel plate. As shown in Figure 4; the sampling frequency is 2048Hz, the excitation head is a steel head, and the excitation force is 45N.

Embodiment 2: free height damping and vibration reduction silent steel rail

The difference from Example 1 is that the damping and vibration-absorbing silent steel rails are freely raised, the thickness of the damping layer A is 3mm, the thickness of the cushioning layer is 18mm, and the thickness of the damping layer I is 3mm. Wherein, a corundum layer inlaid on the surfaces of the cushion layer and the damping layer A is provided, the quantity of the corundum is 0.5kg/m ² , and the particle size of the corundum is 1.8mm.

The preparation of the carbon nanotube modified polyurethane foam, in the step (3), react the B component mixed with the hydroxylated carbon nanotube and the A component isocyanate at a temperature of 80°C and a pressure of 15MPa , the carbon nanotube modified polyurethane foam can be obtained. The interval between the adjacent hollow grooves is not less than 5mm; the hole diameter of the hollow grooves is 5mm.

The preparation method of the free pad height damping and vibration reduction mute rail, the specific steps of the sandblasting treatment are: the spraying timing is 8 seconds after spraying the damping material; the sandblasting air pressure is 0.7MPa, the sandblasting distance is 1 meter, and the temperature is 25°C .

Embodiment 3: free height damping and vibration reduction silent steel rail

The difference from Example 1 is that the damping and vibration-damping silent steel rails are freely raised, the thickness of the damping layer A is 4mm, the thickness of the cushioning layer is 22mm, and the thickness of the damping layer I is 4mm.

Embodiment 4: Constraint Pad High Damping Vibration Damping Silent Steel Rail

The difference from Example 1 is that the restraint pad height damps the vibration-absorbing silent steel rail, and the side of the damping layer I away from the damping unit is further provided with a constraining layer, and the constraining layer is a steel plate. The thickness of the damping layer A is 2mm, the thickness of the cushion layer is 15mm, and the thickness of the damping layer I is 2mm. The quantity of the corundum is 1.5kg/m2, and the particle diameter of the corundum is 2.0mm.

In the preparation of the carbon nanotube-modified polyurethane foam, step (3) reacts the B component mixed with the hydroxylated carbon nanotubes and the A component isocyanate at a temperature of 60°C and a pressure of 16MPa to obtain Carbon nanotube modified polyurethane foam. The interval between the adjacent hollow grooves is not less than 6mm; the hole diameter of the hollow grooves is 6mm.

The preparation method of the restrained pad height damping and vibration-reducing silent steel rail, step (3) continues to spray damping material on carbon nanotube modified polyurethane foam, obtains damping layer I; Constraint layer, can obtain the restrained heightened damping vibration damping silent steel rail in the padding damping vibration reducing silent steel rail. The specific steps of the sandblasting treatment are as follows: the spraying timing is 9 seconds after the damping material is sprayed; the sandblasting air pressure is 0.8 MPa, the sandblasting distance is 1 meter, and the temperature is 22°C.

Embodiment 5: Constraint Pad High Damping Vibration Damping Silent Steel Rail

The difference from Example 4 is that the damping and vibration-damping silent rails are constrained, the thickness of the damping layer A is 3mm, the thickness of the cushioning layer is 16mm, and the thickness of the damping layer I is 3mm. The quantity of the corundum is 0.8kg/m ² , and the particle size of the corundum is 1.9mm.

In the preparation of the carbon nanotube-modified polyurethane foam, the step (3) reacts the B component mixed with the hydroxylated carbon nanotubes and the A component isocyanate at a temperature of 65°C and a pressure of 17.5MPa. Obtain carbon nanotube modified polyurethane foam. The interval between the adjacent hollow grooves is not less than 4.5mm; the hole diameter of the hollow grooves is 5.5mm.

The preparation method of restrained height damping and vibration reduction mute steel rail, step (4) wraps the steel plate that thickness is 1mm in damping layer I as constraining layer, can obtain the restraint height damping vibration reduction mute in the height damping damping and silence rail rails. The specific steps of the sandblasting treatment are as follows: the spraying timing is 9 seconds after the damping material is sprayed; the sandblasting air pressure is 0.7 MPa, the sandblasting distance is 1 meter, and the temperature is 24°C.

Embodiment 6: Constraint Pad High Damping Vibration Damping Silent Steel Rail

The difference from Example 4 is that the damping and vibration-damping silent rails are restrained, the thickness of the damping layer A is 1mm, the thickness of the cushioning layer is 14mm, and the thickness of the damping layer I is 1mm.

Embodiment 7: Multi-layer constrained pad height damping vibration reduction silent steel rail

The difference from Example 1 is that the multi-layer restraint pad height damping damping mute steel rail, the side of the damping layer 1 far away from the damping unit is also provided with a constraining layer and the constraining layer is a steel plate; the number of the damping unit is 2 . The thickness of the damping layer A is 1 mm, the thickness of the cushion layer is 10 mm, and the thickness of the damping layer I is 1 mm. The quantity of the corundum is 1.2kg/m ² , and the particle size of the corundum is 1.7mm.

The preparation of the carbon nanotube-modified polyurethane foam, step (3) reacts the B component mixed with the hydroxylated carbon nanotubes and the A component isocyanate at a temperature of 75°C and a pressure of 16.5MPa, then Obtain carbon nanotube modified polyurethane foam. The interval between the adjacent hollow grooves is not less than 5.5mm; the hole diameter of the hollow grooves is 4.5mm.

The preparation method of the multi-layer constrained pad height damping vibration-absorbing silent steel rail also includes the step (2a) between the step (2) and the step (3): on the carbon nanotube modified polyurethane foam of the damping unit of the outermost layer Continue to spray the damping material, sandblasting; pouring the carbon nanotube modified polyurethane foam as the cushion layer; repeat step (2a), until the number of damping units reaches the requirements; (4) wrapping the damping layer I with a thickness of 3mm The steel plate is used as the constraining layer, and the multi-layer constrained heightening, damping, vibration-reducing and silent steel rail in the raised-damping, vibration-reducing and quiet steel rail can be obtained.

Embodiment 8: Multi-layer constrained pad height damping vibration reduction silent steel rail

The difference from Embodiment 7 is that the number of the damping units is three for the multi-layer constrained pad height damping vibration damping silent steel rail. The thickness of the damping layer A is 1.5mm, the thickness of the cushion layer is 12mm, and the thickness of the damping layer I is 1.5mm. The quantity of the corundum is 1.0 kg/m ² , and the particle size of the corundum is 1.8 mm.

In the preparation of the carbon nanotube-modified polyurethane foam, step (3) reacts component B mixed with hydroxylated carbon nanotubes and component A isocyanate at a temperature of 70°C and a pressure of 17MPa to obtain Carbon nanotube modified polyurethane foam. The interval between the adjacent hollow grooves is not less than 5mm; the hole diameter of the hollow grooves is 5mm.

The preparation method of the multi-layer constrained pad height damping and vibration-reducing mute rail comprises the following steps: repeating step (2a) twice; (4) wrapping a steel plate with a thickness of 2 mm on the damping layer I as the constrained layer to obtain the pad height The multi-layer constraint pad in the damping and vibration-damping silent steel rail heightens the damping and vibration-damping silent steel rail.

Embodiment 9: Multi-layer constrained pad height damping vibration reduction silent steel rail

The difference from Embodiment 7 is that the number of the damping units is three for the multi-layer constrained pad height damping vibration damping silent steel rail. The thickness of the damping layer A is 0.5mm, the thickness of the cushion layer is 8mm, and the thickness of the damping layer I is 0.5mm.

The preparation method of the multi-layer constrained pad height damping and vibration-reducing mute rail comprises the following steps: repeating step (2a) twice; (4) wrapping a steel plate with a thickness of 2 mm on the damping layer I as the constrained layer to obtain the pad height The multi-layer constraint pad in the damping and vibration-damping silent steel rail heightens the damping and vibration-damping silent steel rail.

Table 1 Example 1-9 test result list

first order loss factor second order loss factor Total value of vibration acceleration blank steel plate 0.014 0.016 158.0 Example 1 0.134 0.167 144.5 Example 2 0.125 0.156 145.1 Example 3 0.129 0.161 144.8 Example 4 0.161 0.196 140.6 Example 5 0.169 0.201 140.1 Example 6 0.155 0.189 141.9 Example 7 0.193 0.234 139.2 Example 8 0.224 0.257 138.0 Example 9 0.212 0.243 138.5

The loss factor represents the energy dissipation capacity of the structure, the larger the better; the total vibration acceleration value indicates the vibration of the structure, the smaller the better. It can be seen from Table 1 that compared with the blank steel plate, the loss factor of the vibration-damping, noise-reducing and silent rail prepared in Examples 1-9 increases by an order of magnitude, and the total level of vibration acceleration decreases by 13-20dB. Among them, Example 8 has the best effect. Compared with the blank board, the total value of vibration acceleration can be reduced by 20dB; compared with the blank board, the total value of vibration acceleration in other cases is significantly lower, and the loss factor is significantly increased compared with the blank board. . It shows that the damping and noise reduction effect of the multi-layer constrained pad height damping and silent rail is the best.

Claims (10)

1. padded damping vibration attenuation silencing steel rail, it is characterised in that：Including rail basic unit, damping unit and damping layer I, the damping Unit includes damping layer A and pad level, and the pad level is located near the side of damping layer I, and the damping layer A is located near steel The side of base of the rail layer；The pad level is 4-16 with the thickness ratio of damping layer A；The pad level is with the thickness ratio of damping layer I 4-16；The pad level is carbon nano-tube modification polyurethane foam；The preparation of the carbon nano-tube modification polyurethane foam includes Following steps：(1) CNT is modified, obtains hydroxylated CNT；(2) what step (1) was obtained is hydroxylated CNT is added in the B component for preparing pad level foam, i.e. hydroxy compounds；(3) hydroxylating carbon will be mixed with to receive The B component of mitron is reacted with component A isocyanates, you can obtain carbon nano-tube modification polyurethane foam.

2. padded damping vibration attenuation silencing steel rail according to claim 1, it is characterised in that：The poly- ammonia of carbon nano-tube modification Some grooves are evenly distributed with ester foam, the aperture of the groove is 4-6mm, the interval between the adjacent hollow groove Not less than 4-6mm.

3. padded damping vibration attenuation silencing steel rail according to claim 1 and 2, it is characterised in that：It is anti-in the step (3) Answer 60-80 DEG C of temperature, reaction pressure 15-18MPa.

4. padded damping vibration attenuation silencing steel rail according to claim 3, it is characterised in that：The damping layer I is away from damping The side of unit is additionally provided with restraint layer, and the restraint layer is steel plate；The quantity of the damping unit is 1-3.

5. padded damping vibration attenuation silencing steel rail according to claim 3, it is characterised in that：It is padded in the damping unit The silicon carbide layer for being embedded in the two surface is equipped between layer and damping layer A, the quantity of the diamond dust is 0.5-1.5kg/m², The particle diameter of the diamond dust is 1.6-2.0mm.

6. the preparation method of padded damping vibration attenuation silencing steel rail, it is characterised in that：Comprise the following steps：(1) in rail basic unit Side spraying damping material obtains damping layer A, then carries out blasting treatment；(2) poured as padded on damping layer A after processing The carbon nano-tube modification polyurethane foam of layer, completes a damping unit；(3) continue on carbon nano-tube modification polyurethane foam Spraying damping material obtains damping layer I；The padded damping vibration attenuation of freedom that can obtain in padded damping vibration attenuation silencing steel rail is Jing Yin Rail.

7. the preparation method of padded damping vibration attenuation silencing steel rail according to claim 6, it is characterised in that：The damping layer The thickness of A is 3-5mm, and the thickness of the pad level is 18-22mm, and the thickness of the damping layer I is 3-5mm.

8. the preparation method of padded damping vibration attenuation silencing steel rail according to claim 6, it is characterised in that：Also include step (4)：It is the steel plate of 1-3mm as restraint layer in damping layer I outer wrappings thickness, you can in obtaining padded damping vibration attenuation silencing steel rail The padded damping vibration attenuation silencing steel rail of constraint；The thickness of the damping layer A is 1-3mm, and the thickness of the pad level is 14- 16mm, the thickness of the damping layer I is 1-3mm.

9. the preparation method of padded damping vibration attenuation silencing steel rail according to claim 6, it is characterised in that：Also include being located at The step of between step (2) and step (3) (2a)：On the carbon nano-tube modification polyurethane foam of outermost damping unit after Continuous spraying damping material, blasting treatment；Then pour as the carbon nano-tube modification polyurethane foam of pad level；Repeat step Suddenly (2a), until the quantity of damping unit reaches requirement；Step (4)：In damping layer I outer wrappings thickness for the steel plate of 1-3mm is made It is restraint layer, you can the multilayer obtained in padded damping vibration attenuation silencing steel rail constrains padded damping vibration attenuation silencing steel rail；The resistance The thickness of Buddhist nun's layer A is 0.5-1.5mm, and the thickness of the pad level is 8-12mm, and the thickness of the damping layer I is 0.5- 1.5mm。

10. the preparation method of padded damping vibration attenuation silencing steel rail according to claim 9, it is characterised in that：The sandblasting What is processed concretely comprises the following steps：Spraying opportunity is 8-10s after spraying damping material；Sandblasting air pressure is 0.6-0.8MPa, sandblasting distance It is 1m, temperature is 15-25 DEG C.