Spraying method of environment-friendly vibration and noise reduction polyurethane substitute material for bridge expansion joints

Abstract

The invention belongs to the technical field of bridge construction, and provides a spraying method of an environment-friendly vibration and noise reduction polyurethane substitute material for a bridge expansion joint, which comprises the following steps of: cleaning up the bridge expansion joint, removing greasy dirt, floating ash and loose parts, and ensuring that the flatness error of a base layer does not exceed 3mm; an environment-friendly foaming material is selected, so that the mechanical property and the thermal stability are improved; uniformly spraying the environment-friendly foaming material on the surface of the bridge expansion joint by using spraying equipment to form a vibration and noise reduction layer with a certain thickness; the environment-friendly foaming material adopted by the invention has no pollution to the environment in the production and use processes, conforms to the modern green building concept, has excellent mechanical properties and thermal stability, can keep vibration and noise reduction effects for a long time, and reduces the maintenance cost; the vibration and noise reduction layer formed through the spraying process can effectively absorb and disperse vibration and noise generated when a vehicle passes through, and the driving comfort is remarkably improved.

Description

Technical Field

[0001] The invention belongs to the technical field of bridge construction, and in particular relates to a method for spraying an environmentally friendly bridge expansion joint vibration-damping and noise-reducing polyurethane substitute material. Background Art

[0002] Bridge expansion joints refer to the expansion joints that are usually set between the two beam ends, between the beam ends and the abutments, or at the hinged positions of the bridge to meet the requirements of bridge deck deformation. The function of bridge expansion joints is to adjust the displacement and connection between the superstructures caused by vehicle loads and bridge construction materials.

[0003] During the use of existing bridge expansion joints, due to the influence of factors such as vehicle load and temperature changes, the vehicle often jumps at the joints, seriously affecting driving comfort and safety; at the same time, traditional noise reduction and shock absorption fillers such as polyurethane have problems of aging and cracking during long-term use, and some materials may cause pollution to the environment.

[0004] To this end, those skilled in the art have proposed a method for spraying an environmentally friendly bridge expansion joint vibration-damping and noise-reducing polyurethane alternative material to solve the problems raised by the background technology. Summary of the invention

[0005] In order to solve the above technical problems, the present invention provides a spraying method of an environmentally friendly bridge expansion joint vibration-damping and noise-reducing polyurethane alternative material to solve the problem that in the prior art, during the use of bridge expansion joints, due to the influence of factors such as vehicle load and temperature changes, the vehicle often jumps at the joints, seriously affecting driving comfort and safety; at the same time, traditional noise-reducing and shock-absorbing fillers such as polyurethane and other materials have problems such as aging and cracking during long-term use, and some materials may cause pollution to the environment.

[0006] A method for spraying an environmentally friendly bridge expansion joint vibration-reducing and noise-reducing polyurethane alternative material comprises the following steps:

[0007] S1. Clean the expansion joints of the bridge, remove oil stains, floating dust and loose parts, and ensure that the flatness error of the base does not exceed 3mm;

[0008] S2. Select environmentally friendly foaming materials, which are made by mixing basic polyurethane raw materials with glass fiber, calcium carbonate and additives to improve their mechanical properties and thermal stability;

[0009] S3. Use spraying equipment to evenly spray the above-mentioned environmentally friendly foaming material on the surface of the bridge expansion joint to form a vibration reduction and noise reduction layer of a certain thickness; during the spraying process, the spraying thickness and uniformity must be controlled to ensure that there is no leakage;

[0010] S4. After spraying, use accelerated curing technology to make the vibration and noise reduction layer reach the strength and stability required by the design;

[0011] S5. Carry out acceptance inspection on the sprayed vibration and noise reduction layer to ensure that its flatness, strength and noise reduction effect meet the design requirements.

[0012] Preferably, in step S1, the ratio of the environmentally friendly foaming material is: basic polyurethane raw material accounts for 60%-80%, glass fiber accounts for 5%-15%, calcium carbonate accounts for 5%-15%, and the rest is auxiliary agents, which include cross-linking agents, chain extenders, antioxidants, and heat stabilizers.

[0013] Preferably, the preparation steps of the environmentally friendly foaming material are as follows:

[0014] S11. First, select basic polyurethane raw materials, glass fiber and calcium carbonate that meet the quality standards and are free of impurities, as well as cross-linking agents, chain extenders, antioxidants and heat stabilizers;

[0015] S12, then adding the basic polyurethane raw material, glass fiber, calcium carbonate and cross-linking agent, chain extender, antioxidant, and heat stabilizer into a high-speed mixer in proportion and stirring them fully to make the various raw materials evenly mixed. During the mixing, the raw materials undergo a prepolymerization reaction to form a prepolymer with viscosity;

[0016] S13, then the prepolymer is mixed again with the remaining additives, glass fiber and calcium carbonate, and the molecular chain length is further increased through chain extension reaction, while the glass fiber and calcium carbonate play a reinforcing and filling role, thereby improving the overall performance of the material;

[0017] S14. It is best to discharge the uniformly mixed foaming material to obtain an environmentally friendly foaming material.

[0018] Through the above preparation process, an environmentally friendly bridge expansion joint vibration and noise reduction polyurethane alternative material with excellent mechanical properties and thermal stability can be prepared.

[0019] Preferably, in step S3, the spraying equipment has the function of adjusting the spraying pressure and flow rate to meet the spraying requirements of different bridge expansion joints.

[0020] Preferably, the step S3 is specifically described as follows:

[0021] S31. First, select a spraying device with adjustable spraying pressure and flow rate;

[0022] S32. Before spraying, set appropriate spraying pressure and flow rate according to the characteristics of the environmentally friendly foaming material and the specific conditions of the bridge expansion joint;

[0023] S33. When spraying, the operator first needs to hold the spraying equipment and move it at a uniform speed on the surface of the bridge expansion joint. When spraying, it is necessary to ensure that the nozzle of the spraying equipment is kept 20 cm away from the surface of the bridge expansion joint, and move in a straight line or curve along the direction of the expansion joint to achieve uniform spraying. At the same time, during the spraying process, adjacent spraying areas need to be sprayed overlappingly to ensure the continuity and uniformity of the coating;

[0024] S34. Then use the measuring tool thickness gauge to detect the thickness of the coating; ensure that the thickness of the coating meets the design requirements and is controlled within the allowable error range;

[0025] S35. Finally, after spraying is completed, the expansion joints of the bridge are thoroughly inspected, including edges and corners that are difficult to spray, to ensure that there are no missed spraying and the coating is fully covered.

[0026] By selecting appropriate spraying equipment, setting reasonable spraying parameters, mastering correct spraying techniques and strictly controlling thickness and uniformity, it can be ensured that the environmentally friendly foaming material is evenly sprayed on the surface of the bridge expansion joint to form a vibration reduction and noise reduction layer that meets the requirements.

[0027] Preferably, in step S4, the accelerated curing technology uses heating or ultraviolet irradiation technology, which can shorten the curing time and improve the curing quality;

[0028] Heating technology: First, choose heating equipment with a high-precision temperature control system, such as a hot air circulation oven or a resistance wire heating furnace. According to the curing characteristics of different materials, accurately set and adjust the required curing temperature, and then use a hot air circulation system or a reasonable layout of heating elements to ensure that the temperature distribution of each area in the heating equipment is uniform. At the same time, before heating, preheat the equipment to eliminate temperature gradients and improve temperature uniformity. Then set the heating time according to the type, thickness and curing characteristics of the material. During the heating process, the temperature and time can be adjusted in stages. The low temperature, medium temperature and high temperature operation modes can be used to process the material to meet the needs of the material at different curing stages.

[0029] Ultraviolet irradiation technology: First, select a light source device with stable output and uniform light distribution, such as ultraviolet LED lamps or ultraviolet lamps. Then, select the appropriate light source type and wavelength according to the characteristics and requirements of the curing material; then, optimize the type and amount of photosensitizer added to improve the material's sensitivity to ultraviolet rays and the curing speed. During work, keep the curing environment clean and dry to avoid the effects of dust and moisture on the curing process. Then, design an appropriate reflective structure on the curing equipment to allow ultraviolet rays to more fully irradiate the material surface, improve curing efficiency and uniformity, and ensure that the reflective structure does not cause excessive concentration or scattering of light, thereby avoiding damage to the material or uneven curing.

[0030] At the same time, during the implementation of the accelerated curing technology, an appropriate support structure or fixture is used to suppress the generation of bulges.

[0031] Compared with the prior art, the present invention has the following beneficial effects:

[0032] 1. The environmentally friendly foam material used in the present invention has no pollution to the environment during production and use, conforms to the concept of modern green building, and has excellent mechanical properties and thermal stability, can maintain the vibration reduction and noise reduction effect for a long time, and reduce maintenance costs.

[0033] 2. The vibration and noise reduction layer formed by the spraying process of the present invention can effectively absorb and disperse the vibration and noise generated when the vehicle passes, and significantly improve driving comfort.

[0034] 3. The spraying process of the present invention is simple and quick, does not require complicated construction equipment and technicians, reduces construction difficulty and cost, is suitable for expansion joint treatment of various types of bridges, and has high promotion and application value. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 The present invention is a flow chart of a method for spraying an environmentally friendly bridge expansion joint vibration-damping and noise-reducing polyurethane alternative material. DETAILED DESCRIPTION

[0036] The following embodiments of the present invention are described in further detail in conjunction with the accompanying drawings and examples. The following examples are used to illustrate the present invention, but are not intended to limit the scope of the present invention.

[0037] like Figure 1 As shown:

[0038] Embodiment 1: The present invention provides a method for spraying an environmentally friendly bridge expansion joint vibration-reducing and noise-reducing polyurethane alternative material, comprising the following steps:

[0039] S1. Clean the expansion joints of the bridge, remove oil stains, floating dust and loose parts, and ensure that the flatness error of the base does not exceed 3mm;

[0040] S2. Select an environmentally friendly foaming material, which is a mixture of a basic polyurethane raw material, glass fiber, calcium carbonate and an additive to improve its mechanical properties and thermal stability; the ratio of the environmentally friendly foaming material is: the basic polyurethane raw material accounts for 60%-80%, the glass fiber accounts for 5%-15%, the calcium carbonate accounts for 5%-15%, and the rest is an additive, which includes a cross-linking agent, a chain extender, an antioxidant, and a thermal stabilizer;

[0041] S3, using a spraying device to evenly spray the above-mentioned environmentally friendly foaming material on the surface of the bridge expansion joint to form a vibration reduction and noise reduction layer of a certain thickness; during the spraying process, the spraying thickness and uniformity need to be controlled to ensure that there is no leakage; the spraying equipment has the function of adjusting the spraying pressure and flow rate to meet the spraying requirements of different bridge expansion joints;

[0042] S4. After spraying, the foaming material is subjected to accelerated curing technology to make the vibration reduction and noise reduction layer reach the strength and stability required by the design; the accelerated curing technology uses heating or ultraviolet irradiation technology, which can shorten the curing time and improve the curing quality;

[0043] S5. Carry out acceptance inspection on the sprayed vibration and noise reduction layer to ensure that its flatness, strength and noise reduction effect meet the design requirements.

[0044] From the above, it can be seen that the environmentally friendly foaming material used in the present invention has no pollution to the environment during production and use, conforms to the concept of modern green building, and has excellent mechanical properties and thermal stability, can maintain the vibration reduction and noise reduction effect for a long time, and reduce maintenance costs; the vibration reduction and noise reduction layer formed by the spraying process of the present invention can effectively absorb and disperse the vibration and noise generated when the vehicle passes, and significantly improve driving comfort.

[0045] Specifically, the preparation steps of the environmentally friendly foaming material are as follows:

[0046] S11. First, select basic polyurethane raw materials, glass fiber and calcium carbonate that meet the quality standards and are free of impurities, as well as cross-linking agents, chain extenders, antioxidants and heat stabilizers;

[0047] S12, then adding the basic polyurethane raw material, glass fiber, calcium carbonate and cross-linking agent, chain extender, antioxidant, and heat stabilizer into a high-speed mixer in proportion and stirring them fully to make the various raw materials evenly mixed. During the mixing, the raw materials undergo a prepolymerization reaction to form a prepolymer with viscosity;

[0048] S13, then the prepolymer is mixed again with the remaining additives, glass fiber and calcium carbonate, and the molecular chain length is further increased through chain extension reaction, while the glass fiber and calcium carbonate play a reinforcing and filling role to improve the overall performance of the material;

[0049] S14. It is best to discharge the uniformly mixed foaming material to obtain an environmentally friendly foaming material.

[0050] It can be seen from the above that through the above preparation steps, an environmentally friendly bridge expansion joint vibration and noise reduction polyurethane alternative material with excellent mechanical properties and thermal stability can be prepared.

[0051] More specifically, step S3 is described as follows:

[0052] S31. First, select a spraying device with adjustable spraying pressure and flow rate;

[0053] S32. Before spraying, set appropriate spraying pressure and flow rate according to the characteristics of the environmentally friendly foaming material and the specific conditions of the bridge expansion joint;

[0054] S33. When spraying, the operator first needs to hold the spraying equipment and move it at a uniform speed on the surface of the bridge expansion joint. When spraying, it is necessary to ensure that the nozzle of the spraying equipment is kept 20 cm away from the surface of the bridge expansion joint, and move in a straight line or curve along the direction of the expansion joint to achieve uniform spraying. At the same time, during the spraying process, adjacent spraying areas need to be sprayed overlappingly to ensure the continuity and uniformity of the coating;

[0055] S34. Then use the measuring tool thickness gauge to detect the thickness of the coating; ensure that the thickness of the coating meets the design requirements and is controlled within the allowable error range;

[0056] S35. Finally, after spraying is completed, the expansion joints of the bridge are thoroughly inspected, including edges and corners that are difficult to spray, to ensure that there are no missed spraying and the coating is fully covered.

[0057] From the above, it can be seen that the present invention can ensure that the environmentally friendly foaming material is evenly sprayed on the surface of the bridge expansion joint to form a vibration reduction and noise reduction layer that meets the requirements by selecting suitable spraying equipment, setting reasonable spraying parameters, mastering correct spraying techniques and strictly controlling thickness and uniformity.

[0058] Comparative Example: A method for spraying a bridge expansion joint comprises the following steps:

[0059] Step 1: Cleaning and drying: First, use electric tools to polish and remove loose and powdered layers on the surface of the concrete guardrail to ensure that the surface is flat and clean, and remove dust, sewage, grease, slurry, paint and other external materials on the concrete surface that hinder the penetration of spraying materials; at the same time, dry the concrete substrate to ensure that the surface is completely dry. Do not spray when it rains or there is strong wind or strong sunlight;

[0060] Step 2: Check before spraying: The age of concrete to be sprayed with silane should be no less than 20 days, or no less than 14 days after concrete repair; check whether the concrete surface temperature is between 5℃ and 40℃ to ensure suitable construction conditions;

[0061] Step 3: Low-pressure spraying: Use low-pressure spraying method and spray twice; the spraying interval is 4 to 6 hours to ensure that the upper layer is completely cured to achieve a higher penetration depth;

[0062] Step 4: Spraying operation: Spraying should be carried out continuously to make the coated surface saturated and overflowed; when constructing on a horizontal surface, spray or brush until the surface of the substrate is completely wet or mirror-like, and ensure a "glossy" wet film effect for at least 5 seconds.

[0063] The spraying method of the environmentally friendly bridge expansion joint vibration and noise reduction polyurethane alternative material of the above embodiment and the spraying method of the bridge expansion joint of comparative example 1 were tested for performance, and the test results are shown in the following table:

[0064]

[0065]

[0066] It can be seen from the above test results that the spraying method of the environmentally friendly bridge expansion joint vibration-damping and noise-reducing polyurethane alternative material in the embodiment of the present invention is significantly superior to the conventional bridge expansion joint spraying method in terms of mechanical properties and thermal stability, environmental protection, construction technology, vibration-damping and noise-reduction effects, curing technology, curing time and quality, scope of application, construction difficulty and cost. The spraying process of the present invention is simple and fast, does not require complicated construction equipment and technicians, reduces construction difficulty and cost, is suitable for expansion joint treatment of various types of bridges, and has a high value of promotion and application.

[0067] The embodiments of the present invention are provided for the purpose of illustration and description. Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limitations of the present invention. Ordinary technicians in this field can change, modify, replace and modify the above embodiments within the scope of the present invention.

Claims

1. A spraying method for an environmentally friendly bridge expansion joint vibration and noise reduction polyurethane alternative material, characterized in that: The following steps are involved: S1. Clean the expansion joints of the bridge, remove oil stains, floating dust and loose parts, and ensure that the flatness error of the base does not exceed 3mm; S2. Select environmentally friendly foaming materials, which are made by mixing basic polyurethane raw materials with glass fiber, calcium carbonate and additives to improve their mechanical properties and thermal stability; S3. Use spraying equipment to evenly spray the above-mentioned environmentally friendly foaming material on the surface of the bridge expansion joint to form a vibration reduction and noise reduction layer of a certain thickness; during the spraying process, the spraying thickness and uniformity must be controlled to ensure that there is no leakage; S4. After spraying, use accelerated curing technology to make the vibration and noise reduction layer reach the strength and stability required by the design; S5. Carry out acceptance inspection on the sprayed vibration and noise reduction layer to ensure that its flatness, strength and noise reduction effect meet the design requirements.

2. A spraying method for an environmentally friendly bridge expansion joint vibration and noise reduction polyurethane alternative material as claimed in claim 1, characterized in that: In step S1, the ratio of the environmentally friendly foaming material is: basic polyurethane raw material accounts for 60%-80%, glass fiber accounts for 5%-15%, calcium carbonate accounts for 5%-15%, and the rest is auxiliary agents, which include cross-linking agents, chain extenders, antioxidants, and thermal stabilizers.

3. A spraying method for an environmentally friendly bridge expansion joint vibration and noise reduction polyurethane alternative material as claimed in claim 2, characterized in that: The preparation steps of the environmentally friendly foaming material are as follows: S11. First, select basic polyurethane raw materials, glass fiber and calcium carbonate that meet the quality standards and are free of impurities, as well as cross-linking agents, chain extenders, antioxidants and heat stabilizers; S12, then adding the basic polyurethane raw material, glass fiber, calcium carbonate and cross-linking agent, chain extender, antioxidant, and heat stabilizer into a high-speed mixer in proportion and stirring them fully to make the various raw materials evenly mixed. During the mixing, the raw materials undergo a prepolymerization reaction to form a prepolymer with viscosity; S13, then the prepolymer is mixed again with the remaining additives, glass fiber and calcium carbonate, and the molecular chain length is further increased through chain extension reaction, while the glass fiber and calcium carbonate play a reinforcing and filling role to improve the overall performance of the material; S14. It is best to discharge the uniformly mixed foaming material to obtain an environmentally friendly foaming material.

4. The spraying method of the environmentally friendly bridge expansion joint vibration and noise reduction polyurethane alternative material as claimed in claim 1, characterized in that: In step S3, the spraying equipment has the function of adjusting the spraying pressure and flow rate to meet the spraying requirements of different bridge expansion joints.

5. The spraying method of the environmentally friendly bridge expansion joint vibration and noise reduction polyurethane alternative material as claimed in claim 1, characterized in that: The step S3 is specifically described as follows: S31. First, select a spraying device with adjustable spraying pressure and flow rate; S32. Before spraying, set appropriate spraying pressure and flow rate according to the characteristics of the environmentally friendly foaming material and the specific conditions of the bridge expansion joint; S33. When spraying, the operator first needs to hold the spraying equipment and move it at a uniform speed on the surface of the bridge expansion joint. When spraying, it is necessary to ensure that the nozzle of the spraying equipment is kept 20 cm away from the surface of the bridge expansion joint, and move in a straight line or curve along the direction of the expansion joint to achieve uniform spraying. At the same time, during the spraying process, adjacent spraying areas need to be sprayed overlappingly to ensure the continuity and uniformity of the coating; S34. Then use the measuring tool thickness gauge to detect the thickness of the coating; ensure that the thickness of the coating meets the design requirements and is controlled within the allowable error range; S35. Finally, after spraying is completed, the expansion joints of the bridge are thoroughly inspected, including edges and corners that are difficult to spray, to ensure that there are no missed spraying and the coating is fully covered.

6. The spraying method of the environmentally friendly bridge expansion joint vibration and noise reduction polyurethane alternative material as claimed in claim 1, characterized in that: In step S4, the accelerated curing technology uses heating or ultraviolet irradiation technology, which can shorten the curing time and improve the curing quality.

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