High-doping-amount ultra-thin overlay prepared from pretreated waste mixture and preparation method of high-doping-amount ultra-thin overlay

Abstract

The invention belongs to the technical field of road maintenance, and particularly relates to a pretreated waste mixture high-content ultrathin overlay and a preparation method thereof, and the pretreated waste mixture ultrathin overlay comprises the following raw materials: a pretreated waste mixture, a new aggregate, special recycled asphalt and mineral powder. The purpose of the invention is achieved by performing pretreatment modification on the waste milling material to improve the strength and interface cohesiveness of the waste milling material, activating the activity of the original aged asphalt by using the special recycled asphalt, reducing the mixing temperature and the like. The ultra-thin overlay with the pretreated waste milling material mixture and the doping amount larger than 80% can make full use of the advantages of a regeneration technology and an ultra-thin overlay technology, and has the advantages of being environmentally friendly, high in interface cohesiveness and regeneration utilization rate, capable of saving energy and reducing cost, capable of improving pavement performance and the like.

Description

Technical Field

[0001] The invention belongs to the technical field of highway maintenance, and in particular relates to a high-dosage ultra-thin covering surface for pre-processing waste mixture and a preparation method thereof. Background Art

[0002] With the rapid development of my country's highway construction in the early stage, most of the roads have been put into use for a longer period of time, and road diseases have gradually appeared, which have to be faced with maintenance and repair. Every year, more than 20 million tons of waste asphalt mixtures are generated by road maintenance and renovation alone, and this number is increasing at a rate of nearly 15% per year. These waste asphalt mixtures that cannot be processed in time not only occupy a large amount of land resources and affect the ecological environment, but also completely replace the waste asphalt mixtures with new asphalt mixtures to pave the road, which consumes a lot of resources.

[0003] Ultra-thin asphalt overlay technology is a functional asphalt overlay maintenance technology. It is believed that it can effectively prevent or partially repair diseases and various levels of highways and urban roads that need to improve anti-skid and other performance. In recent years, ultra-thin asphalt overlay has been widely used at home and abroad as a refined, lightweight, low-carbon and environmentally friendly road pre-maintenance technology. This technology is a new type of road maintenance technology. Its core is special modified asphalt, special grading and high-performance tack oil. A layer of ultra-thin asphalt overlay with a thickness of 1cm-2.5cm is directly laid on the old road surface using a special construction process.

[0004] To sum up, if we can make full use of milling material recycling technology and ultra-thin covering technology, we can realize the utilization of waste road materials and improve the quality of road maintenance at the same time, solve the shortage of stone materials and save costs, which is of great significance to highway maintenance. Summary of the invention

[0005] The present invention aims to improve the traditional pavement maintenance technology by utilizing the recycled pre-treated milling material as aggregate and the recycled asphalt technology to activate the original aged asphalt, and then adding a modified emulsified asphalt bonding layer to form an ultra-thin cover with a thickness of 1.5cm-2.0cm, thereby providing a green, environmentally friendly, highly efficient, durable, economical and practical ultra-thin cover technology for pre-treated high-admixture milling material, so as to solve the current problems of low utilization rate of milling material, unstable performance, poor durability, etc., and can effectively utilize waste materials to achieve the purpose of protecting the environment and reducing costs.

[0006] The purpose of the present invention is achieved through the following technical solutions:

[0007] A high-dosage ultra-thin overlay of pretreated waste mixture, comprising the following raw materials: pretreated waste mixture, new aggregate, special recycled asphalt, and mineral powder.

[0008] A method for preparing a high-dosage ultra-thin cover for pre-treating waste mixtures, comprising the following steps:

[0009] (1) The milling material recovered from the road surface is crushed and screened through a drum screen, and the single-stage milling material of 5-10 mm after screening is pre-treated for surface interface modification.

[0010] (2) The pre-treated milling material is put into the regeneration drum for heating. The milling material is used in a ratio of 80%-100%, and the remaining ratio is mixed with new aggregate after adjusting the grading.

[0011] (3) Add special recycled asphalt into the regeneration drum, and add mineral powder after wet mixing to form the finished material.

[0012] (4) After transportation, paving, rolling and other construction processes, an ultra-thin cover of 1.5cm-2.0cm is formed.

[0013] Furthermore, the heating temperature of the milling material is 135°C-175°C, the mixing time is 60s, the heating temperature of the recycled asphalt is 100°C-120°C; the mixing temperature of the mixture is 120°C-160°C, the mixing time is 40s-60s; the paving temperature of the mixture is 110°C-140°C.

[0014] Furthermore, the pre-treated milling material is the upper layer milling material of the asphalt pavement, and the upper layer milling material is preferably mainly composed of basalt and diabase.

[0015] Furthermore, the new aggregate is preferably mainly composed of hard stones with high compressive strength such as basalt and diabase.

[0016] Furthermore, the dosage of the special recycled asphalt is 1.5%-2.0% of the milling material, and it is a functional recycled asphalt containing a regeneration agent, a warm mix agent, and new asphalt, and the proportion of each component is 0.2-0.4:0.08-0.12:1.0. The regeneration agent contains 80-100 parts of bio-oil, 10-20 parts of plasticizer, 2-4 parts of tackifier, and 1-3 parts of antioxidant. The warm mix agent is a commonly used APTL warm mix agent. The new asphalt is 70# base asphalt.

[0017] Furthermore, the milling material pretreatment in the step is obtained by the following steps:

[0018] a. After screening the recovered milling material, select the single-stage milling material of 5-10mm and put it into the mixer. Stir and spray the silane coupling agent solution at the same time. The stirring rate is 40r / min-60r / min, and the silane coupling agent solution is 1%-3% of the mass of the milling material;

[0019] b. Spraying the silane coupling agent solution to evenly cover and modify the surface of the milling material. Then, the silane coupling agent solution covering the surface is cured and dried at 160℃-170℃ for 2h to make the silane coupling agent firmly attached to the surface of the milling material, thereby achieving the surface modification effect of the milling material;

[0020] Furthermore, the silane coupling agent solution is prepared by mixing silane coupling agent: ethanol: water in a ratio of 5-10:45-50:45-50, and after preparation, the solution is allowed to stand for 30-60 minutes for hydrolysis.

[0021] Furthermore, the silane coupling agent is one or more of silane coupling agents such as KH550, KH560, and KH570.

[0022] Furthermore, the ethanol is an ethanol solution with an ethanol content of 95%.

[0023] Compared with the prior art solutions, the present invention has the following advantages and beneficial effects:

[0024] (1) Green and environmentally friendly. The use of road waste milling materials avoids waste accumulation and waste, while reducing the mining of new stones, protecting the environment, and conforming to the new concept of environmental protection in the construction industry.

[0025] (2) Strong interfacial adhesion. The surface of the milling material is modified by using a silane coupling agent. The silane coupling agent undergoes a hydrolysis reaction when in contact with water in the air and old stone. The product of the hydrolysis reaction forms a polysiloxane film on the surface of the stone, producing a chemical adsorption effect, thereby improving the stability of the milling material. Furthermore, the copolymer produced by the chemical bond between the lipophilic functional groups of the silane coupling agent and the aged asphalt in the milling material forms a covalent network structure, thereby enhancing the interfacial adhesion of the aged asphalt-silane coupling agent-old stone composite.

[0026] (3) High recycling rate. By pre-treating the milling material, the milling material content can be increased to more than 80%, greatly improving the utilization rate of waste materials.

[0027] (4) Energy saving and cost reduction. Compared with the traditional thermal regeneration technology, the present invention has lower mixing temperature and paving temperature in actual mixing, which saves energy. At the same time, the ultra-thin paving thickness is as thin as 1.5cm-2.0cm, the amount of stone used is small, and the regeneration agent is used to activate the performance of the old asphalt of the milling material. The amount of new asphalt is small, and the amount of materials used is reduced. The maintenance cost is reduced.

[0028] (5) Improved road performance. Compared with traditional recycling technology, the road surface paved by the present invention has anti-skid and noise reduction functions, reduces the impact of elevation, and greatly improves road performance. DETAILED DESCRIPTION

[0029] In order to better understand the present invention, the applicant further illustrates the content of the present invention in conjunction with the following embodiments, but the content of the present invention is not limited to the following embodiments.

[0030] Example 1

[0031] A high-dosage ultra-thin cover for pre-treating waste mixture and a preparation method thereof, comprising the following steps:

[0032] (1) The milling material recovered from the road surface is crushed and screened through a drum screen, and the single-stage milling material of 5-10 mm after screening is pre-treated for surface interface modification.

[0033] (2) Surface interface modification steps of recycled milling material pretreatment:

[0034] a. Mix 5 parts of KH550 silane coupling agent, 45 parts of ethanol solution and 50 parts of water to prepare silane coupling agent. After preparation, let it stand for 30 minutes for complete hydrolysis.

[0035] b. Put the modified milling material into the mixer and spray the silane coupling agent solution while stirring. The stirring rate is 40r / min and the silane coupling agent solution is 2% of the mass of the milling material. By spraying the silane coupling agent solution, the surface of the milling material is evenly covered and modified.

[0036] c. Then, the silane coupling agent solution covering the surface is cured by drying and curing it at 170°C for 2 hours, so that the silane coupling agent is firmly bonded to the surface of the milling material, thereby achieving the surface modification effect of the milling material.

[0037] (3) The pretreated milling material is put into the regeneration drum for heating at a temperature of 150°C, a stirring time of 60 seconds, a regeneration drum speed of 50 r / min, and a milling material usage ratio of 85%. The remaining 15% is mixed with new aggregate after adjusting the grading.

[0038] (4) Add special recycled asphalt to the regeneration drum. The amount of special recycled asphalt is 1.5% of the milling material. It is a functional recycled asphalt containing a regeneration agent, an APTL warm mix agent, and 70# new asphalt. The proportion of each component is 0.2:0.08:1.0. The regeneration agent contains 80 parts of bio-oil, 15 parts of plasticizer, 2 parts of viscosity enhancer, and 3 parts of antioxidant. After wet mixing, add the corresponding proportion of mineral powder and mix for 45 seconds to form the finished material.

[0039] (5) Through the construction processes of transportation, paving, rolling, etc., an ultra-thin cover of 1.5 cm is formed.

[0040] Example 2

[0041] A high-dosage ultra-thin cover for pre-treating waste mixture and a preparation method thereof, comprising the following steps:

[0042] (1) The milling material recovered from the road surface is crushed and screened through a drum screen, and the single-stage milling material of 5-10 mm after screening is pre-treated for surface interface modification.

[0043] (2) Surface interface modification steps of recycled milling material pretreatment:

[0044] a. Mix 10 parts of KH550 silane coupling agent, 45 parts of ethanol solution and 45 parts of water to make a silane coupling agent. After the preparation, let it stand for 45 minutes for complete hydrolysis.

[0045] b. Put the modified milling material into the mixer and spray the silane coupling agent solution while stirring. The stirring rate is 45r / min, and the silane coupling agent solution is 1% of the mass of the milling material. By spraying the silane coupling agent solution, the surface of the milling material is evenly covered and modified.

[0046] c. Then, the silane coupling agent solution covering the surface is cured by drying and curing it at 160° C. for 2 hours, so that the silane coupling agent is firmly bonded to the surface of the milling material, thereby achieving the surface modification effect of the milling material.

[0047] (3) The pretreated milling material is put into the regeneration drum for heating at a temperature of 175°C, a stirring time of 60 seconds, a regeneration drum speed of 60 r / min, and a milling material usage ratio of 90%. The remaining 105% is mixed with new aggregate after adjusting the grading.

[0048] (4) Add special recycled asphalt to the regeneration drum. The amount of special recycled asphalt is 2.0% of the milling material. It is a functional recycled asphalt containing a regeneration agent, an APTL warm mix agent, and 70# new asphalt. The proportion of each component is 0.4:0.1:1.0. The regeneration agent contains 90 parts of bio-oil, 10 parts of plasticizer, 3 parts of viscosity enhancer, and 2 parts of antioxidant. After wet mixing, add the corresponding proportion of mineral powder and mix for 45 seconds to form the finished material.

[0049] (5) An ultra-thin cover of 1.8 cm is formed through construction processes such as transportation, paving, and rolling.

[0050] Example 3

[0051] A high-dosage ultra-thin cover for pre-treating waste mixture and a preparation method thereof, comprising the following steps:

[0052] (1) The milling material recovered from the road surface is crushed and screened through a drum screen, and the single-stage milling material of 5-10 mm after screening is pre-treated for surface interface modification.

[0053] (2) Surface interface modification steps of recycled milling material pretreatment:

[0054] a. Mix 8 parts of KH550 silane coupling agent, 45 parts of ethanol solution and 47 parts of water to make a silane coupling agent. After the preparation, let it stand for 50 minutes for complete hydrolysis.

[0055] b. Put the modified milling material into the stirrer and spray the silane coupling agent solution while stirring. The stirring rate is 50r / min, and the silane coupling agent solution is 3.0% of the mass of the milling material. By spraying the silane coupling agent solution, the surface of the milling material is evenly covered and modified.

[0056] c. Then, the silane coupling agent solution covering the surface is cured by drying and curing it at 160° C. for 2 hours, so that the silane coupling agent is firmly bonded to the surface of the milling material, thereby achieving the surface modification effect of the milling material.

[0057] (3) The pretreated milling material is put into the regeneration drum for heating at a temperature of 165°C, a stirring time of 60 seconds, a regeneration drum speed of 55 r / min, and a milling material usage ratio of 85%. The remaining 15% is mixed with new aggregate after adjusting the grading.

[0058] (4) Add special recycled asphalt to the regeneration drum. The amount of special recycled asphalt is 2.0% of the milling material. It is a functional recycled asphalt containing a regeneration agent, an APTL warm mix agent, and 70# new asphalt. The proportion of each component is 0.4:0.12:1.0. The regeneration agent contains 85 parts of bio-oil, 15 parts of plasticizer, 2 parts of viscosity enhancer, and 3 parts of antioxidant. After wet mixing, add the corresponding proportion of mineral powder and mix for 45 seconds to form the finished material.

[0059] (5) Through transportation, paving, rolling and other construction works, a 2.0 cm ultra-thin cover is formed.

[0060] Comparative Example 1

[0061] In the comparative example, new basalt aggregate is used as the aggregate, and the rest is the same as that in Example 3.

[0062] A high-dosage ultra-thin cover for pre-treating waste mixture and a preparation method thereof, comprising the following steps:

[0063] (1) The milling material recovered from the road surface is crushed and screened through a drum screen, and the single-stage milling material of 5-10 mm after screening is pre-treated for surface interface modification.

[0064] (2) Surface interface modification steps of recycled milling material pretreatment:

[0065] a. Mix 8 parts of KH550 silane coupling agent, 45 parts of ethanol solution and 47 parts of water to make a silane coupling agent. After the preparation, let it stand for 50 minutes for complete hydrolysis.

[0066] b. Put the modified milling material into the stirrer and spray the silane coupling agent solution while stirring. The stirring rate is 50r / min, and the silane coupling agent solution is 3.0% of the mass of the milling material. By spraying the silane coupling agent solution, the surface of the milling material is evenly covered and modified.

[0067] c. Then, the silane coupling agent solution covering the surface is cured by drying and curing it at 160° C. for 2 hours, so that the silane coupling agent is firmly bonded to the surface of the milling material, thereby achieving the surface modification effect of the milling material.

[0068] (3) The pretreated milling material is put into the regeneration drum for heating at a temperature of 165°C, a stirring time of 60 seconds, a regeneration drum speed of 55 r / min, and a milling material usage ratio of 85%. The remaining 15% is mixed with new aggregate after adjusting the grading.

[0069] (4) Add special recycled asphalt to the regeneration drum. The amount of special recycled asphalt is 2.0% of the milling material. It is a functional recycled asphalt containing a regeneration agent, an APTL warm mix agent, and 70# new asphalt. The proportion of each component is 0.4:0.12:1.0. The regeneration agent contains 85 parts of bio-oil, 15 parts of plasticizer, 2 parts of viscosity enhancer, and 3 parts of antioxidant. After wet mixing, add the corresponding proportion of mineral powder and mix for 45 seconds to form the finished material.

[0070] (5) Through the construction processes of transportation, paving, rolling, etc., a 2.0 cm ultra-thin cover is formed.

[0071] The milling material mixture recycled samples prepared in Examples 1-3 and Comparative Example 1 were subjected to relevant road performance tests, and the test results are shown in Table 1.

[0072] Table 1 Performance test results of Examples 1-3 and Comparative Example 1

[0073]

Claims

1. A high-dosage ultra-thin overlay of pretreated waste mixture, comprising the following raw materials: pretreated waste mixture, new aggregate, special recycled asphalt, and mineral powder.

2. The high-dosage ultra-thin cover for pre-processing waste mixture according to claim 1, characterized in that: The pre-treated waste mixture is the milling material of the upper layer of the asphalt pavement, and the upper layer of the milling material is preferably mainly basalt and diabase.

3. The high-dosage ultra-thin cover for pre-processing waste mixture according to claim 1, characterized in that: The new aggregate is preferably mainly made of hard stones with high compressive strength such as basalt and diabase.

4. The high-dosage ultra-thin cover for pre-processing waste mixture according to claim 1, characterized in that: The dosage of the special recycled asphalt is 1.5%-2.0% of the milling material. The special recycled asphalt is a functional recycled asphalt containing a regeneration agent, a warm mix agent, and new asphalt. The proportion of each component is 0.2-0.4:0.08-0.12:1.

0.

5. The high-dosage ultra-thin cover for pre-processing waste mixture according to claim 4, characterized in that: The regeneration agent comprises 80-100 parts of bio-oil, 10-20 parts of plasticizer, 2-4 parts of tackifier and 1-3 parts of antioxidant.

6. The high-dosage ultra-thin covering for pre-processing waste mixture according to claim 4, characterized in that: The warm mix agent is APTL warm mix agent.

7. The high-dosage ultra-thin cover for pre-processing waste mixture according to claim 1, characterized in that: The processing steps of the pre-processing waste mixed material are as follows: a. After screening the recovered milling material, select the single-stage milling material of 5-10 mm and put it into the mixer, and spray the silane coupling agent solution while stirring. The stirring rate is 40r / min-60r / min, and the silane coupling agent solution is 1%-3% of the mass of the milling material; b. The surface of the milling material is evenly covered and modified by spraying the silane coupling agent solution, and then the silane coupling agent solution covering the surface is cured and dried at 160°C-170°C for 2 hours to make the silane coupling agent firmly on the surface of the milling material, thereby achieving the surface modification effect of the milling material.

8. The high-dosage ultra-thin covering for pre-processing waste mixture according to claim 7, characterized in that: The silane coupling agent solution comprises a silane coupling agent, ethanol and water in a ratio of 5-10:45-50:45-50. After the preparation is completed, the solution is allowed to stand for 30 minutes to 60 minutes for hydrolysis.

9. The high-dosage ultra-thin covering for pre-processing waste mixture according to claim 8, characterized in that: The silane coupling agent is one or more of silane coupling agents such as KH550, KH560, and KH570.

10. The high-dosage ultra-thin covering for pre-processing waste mixture according to claim 8, characterized in that: The ethanol is an ethanol solution with an ethanol content of 95%.

11. A method for preparing a high-dosage ultra-thin cover for pre-treating waste mixture, comprising the following steps: (1) The milling material recovered from the road surface is crushed and screened through a drum screen, and the single-stage milling material of 5-10 mm after screening is pre-treated to perform surface interface modification; (2) The pre-treated milling material is put into the regeneration drum for heating, the milling material is used in a proportion of 80%-100%, and the remaining proportion is mixed with new aggregate to adjust the grading; (3) Add special recycled asphalt into the regeneration drum, and add mineral powder after wet mixing to form the finished material. (4) After transportation, paving, rolling and other construction processes, an ultra-thin cover of 1.5cm-2.0cm is formed.

12. The method for preparing a high-dosage ultra-thin cover for pre-treated waste mixture according to claim 11, characterized in that: The heating temperature of the milling material is 135°C-175°C, and the mixing time is 60s; the heating temperature of the recycled asphalt is 100°C-120°C; the mixing temperature of the mixture is 120°C-160°C, and the mixing time is 40s-60s; the paving temperature of the mixture is 110°C-140°C.

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