CN115057657A - Paving method of ultra-thin wear layer based on high viscosity emulsified asphalt - Google Patents

Abstract

The invention discloses an ultra-thin wear layer paving method based on high-viscosity emulsified asphalt, which belongs to the field of road engineering. The paving method includes: S1. Spreading high-viscosity emulsified asphalt on the original road surface to form a bonding layer; S2. Paving embedded solid warm mix asphalt mixture and compacting. The high-viscosity emulsified asphalt is composed of a specific proportion of hard petroleum asphalt, SBS latex, rubber powder dispersion, dihydrogenated tallow methyl benzyl ammonium chloride modified nano-silica, methyl glucoside polyoxyethylene ether two It is prepared from oleic acid ester, hydrochloric acid and water, and has outstanding advantages such as good storage stability, fast demulsification, strong adhesion, good high temperature performance, good durability and non-stick wheel. The ultra-thin wear layer not only has outstanding advantages such as waterproof, anti-skid and wear-resistant, but also can be constructed with conventional equipment or integrated equipment, which reduces the technical threshold and investment cost of ultra-thin wear layer, and has good promotion and application value. .

Description

Paving method of ultra-thin wear layer based on high viscosity emulsified asphalt

technical field

The invention relates to the field of road engineering, and in particular provides an ultra-thin wear layer paving method based on high-viscosity emulsified asphalt and a preparation method thereof.

Background technique

Ultra-thin wear layer is an asphalt pavement surface layer technology that combines asphalt mixture and modified emulsified asphalt sticky layer. This technology can reduce the thickness to 1/3-1/2 (≤25mm) of the thickness of the traditional asphalt cover under the premise of achieving the same performance of the road surface, greatly reducing the cost of road maintenance projects, and is based on the full life cycle economy of the net asset value of the road surface. Benefit analysis can save 30%-40% of construction cost and maintenance cost, and has significant social and economic benefits. However, because the ultra-thin wear layer is thin and easy to cool, the compaction effect of the mixture is not ideal, and the void ratio of the pavement decreases rapidly after the road is opened to traffic, resulting in a rapid decline in the anti-skid performance of the pavement, which is likely to cause traffic accidents and affect driving safety. On the other hand, the current ultra-thin wear layers are mostly open-graded or semi-open-graded asphalt mixtures. It is necessary to spread an emulsified asphalt adhesive layer between the layers, and the quality of the emulsified asphalt in the adhesive layer directly affects the bonding effect. To be taken away by the wheel, it is necessary to use integrated construction equipment, which has not yet been domestically produced and is expensive.

SUMMARY OF THE INVENTION

Aiming at the above-mentioned deficiencies of the prior art, the present invention provides an ultra-thin wear layer paving method based on high-viscosity emulsified asphalt with high cohesiveness, high durability and skid resistance.

The technical solution adopted by the present invention to solve the technical problem is: an ultra-thin wear layer paving method based on high-viscosity emulsified asphalt, including:

S1. Spread high-viscosity emulsified asphalt on the original road to form a bonding layer,

According to the mass percentage, the high viscosity emulsified asphalt is prepared from the following raw materials:

S2. Pave embedded solid warm mix asphalt and compact it.

In the high-viscosity emulsified asphalt of the present invention, the hard petroleum asphalt is the main part of the ultra-thin wear layer paving method based on the high-viscosity emulsified asphalt, and the necessary viscosity and softening point of the ultra-thin wear layer paving method based on the high-viscosity emulsified asphalt are provided. , is the main contributor to high adhesion and high temperature performance; the SBS particles in the SBS latex, the rubber powder particles in the rubber powder dispersion and the asphalt particles in the emulsified asphalt can form a relatively uniform dispersion system, which ensures the stability of the emulsion. At the same time, after demulsification, asphalt particles, SBS particles and rubber powder particles are bonded, filled and polymerized to form an integral viscoelastic material, which has good adhesion, high temperature performance and durability; double hydrogenated tallow methyl Benzyl ammonium chloride modified nano-silica and methyl glucoside polyoxyethylene ether dioleate have certain surface activity and nano-scale stability. The synergistic effect of several substances can not only reduce the surface tension, but also help In the formation of asphalt emulsion, it can also play a role in maintaining the stability of the emulsion for a long time. Due to the specific structural properties of each substance, the high-temperature acidification treatment increases its dispersibility in water, and at the same time, the polar functional groups are protonated to better emulsify. In addition, due to the specific linear structure of several substances and the basic functional groups contained, they have a strong adsorption effect after contacting the substrate, and can quickly break the demulsification to meet the construction requirements.

Preferably, the mass percentage of each raw material of the high-viscosity emulsified asphalt is:

Preferably, the penetration of the hard petroleum asphalt is 10-30 (0.1mm), and the softening point is greater than 60°C.

Preferably, the mass percentage of SBS in the SBS latex is greater than 50 wt%, and the block ratio S/B is preferably 3:7.

Preferably, the rubber powder dispersion liquid is composed of rubber powder, suspending agent, dispersing agent and water, and the mass ratio of rubber powder, suspending agent, dispersing agent and water is 10:(0.5-1.5):(0.5-1.5):(1 -3), and the mass percentage of rubber powder is not less than 70%. The particle size of the rubber powder is 30-60 mesh. The suspending agent is preferably magnesium aluminum silicate. The dispersant is preferably sodium polyacrylate. Under the action of dispersing agent and suspending agent, the specific surface of rubber powder is large, and the problem that it is difficult to disperse in the emulsion is solved, making it easier to disperse the rubber powder into the emulsified asphalt.

Preferably, the double-hydrogenated tallow methyl benzyl ammonium chloride modified nano-silica is obtained by modifying the nano-silica with double-hydrogenated tallow methyl benzyl ammonium chloride. Its preparation method includes:

Dissolving 4wt-6wt% dihydrogenated tallow methyl benzyl ammonium chloride in an aqueous hydrochloric acid solution with a pH value of 2-3 at 75°C-90°C to obtain a solution;

adding 18wt-22wt% nano-silicon dioxide to the water solubility of glycerol and stirring evenly, heating to 75°C-90°C to obtain b suspension;

Mix the a solution and the b suspension according to the mass ratio of 1:(0.8-1.2), and react at 75-90 ° C for 12-36 hours. After the reaction is completed, remove the water, and dry and activate it in a vacuum for 8-16 hours to obtain the obtained solution. Described double hydrogenated tallow methyl benzyl ammonium chloride modified nano-silica. The activation temperature is preferably 100-110°C, particularly preferably 103-107°C.

Preferably, the hydrochloric acid of the present invention is concentrated hydrochloric acid with a concentration of 36%-38%.

Preferably, the preparation method based on high viscosity emulsified asphalt comprises the following steps:

S1. Add double hydrogenated tallow methyl benzyl ammonium chloride modified nano-silica and methyl glucoside polyoxyethylene ether dioleate to 80-90 ° C hydrochloric acid aqueous solution to obtain a pH value of 1-3 the soap solution, and then cooled to 50-60 ℃ in a natural state for use;

S2. Heat the hard bitumen to 155-170°C for use;

S3. The soap liquid and asphalt are sent to the colloid mill, ground by the colloid mill, and the hard emulsified asphalt is obtained after heat exchange and cooling;

S4. SBS latex, rubber powder dispersion, and hard emulsified asphalt are mixed and stirred to obtain a pre-dispersed emulsion; after the pre-dispersed emulsion is ground by a colloid mill, a high-viscosity emulsified asphalt is obtained.

Preferably, step S1 is specifically:

First, add hydrochloric acid to the water at room temperature, adjust the pH of the water to about 2±0.5, then heat it to 80-90°C, keep the temperature, and slowly add dihydrogenated tallow methyl benzyl chloride under stirring Ammonium modified nano-silicon dioxide, methyl glucoside polyoxyethylene ether dioleate, continue to stir for 30 minutes, add hydrochloric acid to adjust the pH of the solution to about 2±0.5 to obtain soap liquid, and then cool it in a natural state Reserve at 50-60°C.

Preferably, step S3 includes:

S31. Preheat colloid mill grinding head, asphalt pipeline and soap liquid pipeline;

S32. Increase the outlet pressure of the asphalt pipeline, soap liquid pipeline and colloid mill, and adjust the outlet pressure of the colloid mill to 0.15-0.25MPa. Under this condition, the boiling point of water is raised to about 110°C, which can avoid the instantaneous moisture at the outlet of the colloid mill. That is, evaporation occurs, and local demulsification occurs.

Preferably, in step S31, the colloid mill head is preheated to 100-120°C, the asphalt line is preheated to 150-170°C, and the soap liquid line is preheated to 50-60°C.

Preferably, step S32 includes: cooling the emulsified asphalt that has passed through the colloid mill through a heat exchanger, and the temperature of the cooling water is room temperature.

Preferably, in terms of mass percentage, the embedded warm-mix asphalt mixture of the present invention is composed of 5.5%-8.5% warm-mix high-viscosity modified asphalt, 0.1-0.5% 5mm-7mm chopped untwisted polymer Ester fiber, 70%-75% coarse aggregate, 15%-20% fine aggregate and 6%-12% filler, especially preferably modified by 5.5%-6.5% warm mixing and high viscosity Asphalt, 0.1-0.3% 5mm-7mm chopped untwisted polyester fiber, 70%-73% coarse aggregate, 15%-18% fine aggregate and 6%-8% filler .

Preferably, in terms of mass percentage, the warm-mix high-viscosity modified asphalt is composed of 80-90% AH-70 asphalt, 10-16% high-viscosity asphalt modifier, 0.02-0.04% stabilizer, 0.4% -0.8% compatibilizer, 0.4%-1.0% warm mixing agent.

The high-viscosity modifier is obtained by kneading _C9 petroleum resin, polystyrene-polybutadiene block copolymer SBS, rubber powder, solid rosin and talc powder. In terms of mass percentage, the consumption of each raw material is :

The stabilizer is a sulfur-based stabilizer, such as the modified asphalt stabilizer of Dongying Runfeng Boyue Petroleum Technology Co., Ltd.

The compatibilizer is an extraction oil.

The warm-mixing agent is a palmitic acid imidazoline warm-mixing agent, which is obtained from palmitic acid and tetraethylenepentamine through a two-step reaction of amidation and cyclization.

In the above-mentioned warm-mix high-viscosity modified asphalt, the main function of the C ₉ petroleum resin is to increase the viscosity, SBS and rubber powder have good tackifying and viscoelastic properties, and the solid rosin can make the C ₉ petroleum resin, SBS and rubber. The molecular chain of the powder is lubricated and can be better blended together to play a synergistic effect. The talc powder can prevent the blocking during the preparation of the modifier. The high-viscosity modifier prepared in this way has excellent high-viscosity modification effect on asphalt, and can prepare high-performance cementitious materials that meet the requirements of open-graded or semi-open aggregated asphalt mixtures. Due to the high viscosity of high-viscosity asphalt, it needs to be heated to a very high temperature to meet the requirements of mixing and compaction, and the selected imidazoline palmitate warm mix agent can be easily dissolved in high-viscosity asphalt due to its specific molecular structure. , adsorbed by the high-viscosity modifier, intermolecular lubrication, effectively reducing the friction in the mixing process of the mixture, so that the high-viscosity asphalt mixture used can be constructed at a relatively low temperature. The chopped untwisted polyester fiber has good dispersibility in the mixture, reduces the porosity of the mixture by 1% to 2%, can increase the viscosity, stabilize the asphalt, increase the oil film, and improve the leakage loss and loss of the mixture. Scatter loss, thereby improving the toughness and durability of embedded warm-mix high-viscosity asphalt mixture. In addition, due to the strong cohesion between the asphalt molecules, the warm-mix high-viscosity asphalt mixture and the high-viscosity asphalt after demulsification can be firmly bonded to the original pavement, with strong bonding strength and interlayer resistance. Shear strength, forming a structure as a whole, can increase the stability and durability of the pavement, and has high bonding performance, thereby improving the pavement performance of the ultra-thin asphalt wear layer.

Preferably, the coarse aggregate is basalt or/and diabase crushed stone with a nominal maximum particle size of 9.5 mm and a 4.75 mm sieve pass rate of less than 5%, wherein the crushed stone with a particle size of 6.7 mm-9.5 mm The content is greater than 65%; the fine aggregates are machine-made sand or stone chips processed by alkaline or neutral stone with a 2.36mm sieve opening rate greater than 95% and a 0.075mm sieve opening rate less than 8%; the fillers include Limestone ore powder and slaked lime or cement with a content of less than 2%.

In the above-mentioned embedded warm mix asphalt mixture, by adjusting the gradation and chopped untwisted polyester fibers, the warm mix high viscosity asphalt mixture finally forms a dense intermittent gradation, of which 92% of the 9.5mm sieve holes pass. ～100%, 24%～34% for 4.75mm mesh, 21%～32% for 2.36mm mesh, 13%～27% for 1.18mm mesh, and 13%～27% for 0.6mm mesh 10%～24%, 0.3mm sieve passing percentage is 5%～18%, 0.15mm sieve passing percentage is 7%～12%, 0.075mm sieve passing percentage is 5%～9%. By adjusting the amount of warm-mixed high-viscosity modified asphalt, the porosity of the mixture is between 3-4%, and the oil film thickness is greater than 10um.

As preferably, the present invention is based on the ultra-thin wear layer paving method of high viscosity emulsified asphalt, comprising the following construction steps:

S1. Clean the original road surface and deal with the disease;

S2. Spread 0.3L/m ² -1.2L/m ² high-viscosity emulsified asphalt bonding layer on the original road surface under the condition that the road surface temperature is not lower than 5 ℃;

S3. A layer of embedded warm-mixed high-viscosity modified asphalt mixture with a thickness of 1.6cm-3.0cm is laid on the above-mentioned bonding layer, and the paving temperature is 115-155°C.

S4. Under the condition of 90-145 ℃, the warm-mixed high-viscosity modified asphalt mixture paved in step S3 is rolled, embedded and compacted by a rubber wheel road roller to form a 1.5cm-2.5cm thick road superstructure. Thin wear layer.

Compared with the prior art, the ultra-thin wear layer paving method based on high-viscosity emulsified asphalt and the preparation method thereof of the present invention have the following outstanding beneficial effects:

(1) After being modified by dihydrogenated tallow methyl benzyl ammonium chloride, the dispersibility of nano-silicon dioxide in water and emulsion is greatly improved, which enhances the interfacial strength of the emulsion and plays a stabilizing role, which can increase the basis of high Viscoelasticity and toughness of an ultra-thin wear layer paving method based on viscous emulsified asphalt, thereby improving the durability of an ultra-thin wear layer paving method based on high-viscosity emulsified asphalt.

(2) Dihydrogenated tallow methyl benzyl ammonium chloride modified nano-silicon dioxide, methyl glucoside polyoxyethylene ether dioleate are all insoluble in water, and the present invention is treated by high temperature acidification, so that each The substances play a synergistic role, so that they can be dispersed in water and have a good emulsifying and stabilizing effect.

(3) Hard asphalt can be emulsified at higher temperature to obtain emulsified asphalt with good stability.

(4) SBS particles in SBS latex, rubber powder particles in rubber powder dispersion and medium asphalt particles in emulsified asphalt have the same order of magnitude in particle size through dispersion and shear grinding by colloid mill, so that SBS and rubber powder have the same order of magnitude. In the asphalt that can be dispersed evenly, a homogeneous material is formed, which makes the emulsion have good stability. High temperature stability;

(5) Adopt pipeline pressure treatment and use differential pressure pumping to ensure that the asphalt is delivered to the colloid mill while avoiding the blockage of the asphalt to the colloid mill and cause "paste mill"; the purpose of the colloid mill outlet pressure combined with heat exchange treatment is to Rapidly cooling the emulsion while lowering the boiling point of the exit emulsion can prevent the vaporization of the water in the emulsion, resulting in the "bumping" phenomenon of the emulsion, which affects the quality of the emulsified asphalt.

(6) It can ensure the performance of the ultra-thin wear layer under cooling construction, thereby effectively improving the toughness and durability of the ultra-thin wear layer.

(7) The combined structure design of the high-viscosity emulsified asphalt bonding layer and the warm-mix high-viscosity asphalt mixture makes the mixture system have good viscoelasticity and solves the problem of reflective cracks. At the same time, the high-viscosity asphalt has high adhesion Its use solves the problem of particle loosening and particle dropping caused by the small cohesion of the ultra-thin wear layer. In addition, the overall combined structure design and the addition of fibers to the warm-mix high-viscosity asphalt mixture can significantly improve the high-temperature performance, low-temperature performance and fatigue performance of the mixture. , which improves the service performance and service life of the ultra-thin wear layer.

Detailed ways

The present invention will be further described below with reference to specific embodiments, but it is not intended to limit the present invention.

It should be noted that the following detailed description is exemplary and intended to provide further explanation of the application. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs.

Description of materials for each embodiment of the present invention:

Hard petroleum asphalt: HA-15 type hard petroleum asphalt, penetration 18(0.1mm), softening point 70℃;

SBS latex: the mass percentage of SBS is 50wt%, and the block ratio S/B is 3:7;

Hydrochloric acid: chemically pure, the concentration is 37%.

Rubber powder dispersion: the mass ratio of rubber powder, suspending agent, dispersant and water is 10:1:1:2, the particle size of rubber powder is 30-60 mesh, the suspending agent is magnesium aluminum silicate, the dispersing agent is It is sodium polyacrylate dispersant;

Polystyrene-polybutadiene block copolymer SBS: Linear SBS (791H);

Sulfur stabilizer: modified asphalt stabilizer, purchased from Dongying Runfeng Boyue Petroleum Technology Co., Ltd.

Example 1:

The preparation method of double hydrogenated tallow methyl benzyl ammonium chloride modified nano-silica:

S1. First, add concentrated hydrochloric acid to water at room temperature to adjust the pH to 2-3, then heat it to 80°C, keep the temperature, and slowly add 5wt% dihydrogenated tallow methyl benzyl chloride under stirring Ammonium is completely dissolved to obtain a solution for subsequent use;

S2. 20wt% nano-dioxide is added to the water solubility of glycerol and stirred, and heated to 80 ° C to obtain b suspension for subsequent use;

S3. A solution and b suspension are added to the three-necked flask according to the mass ratio of 1:1, and under magnetic stirring, the temperature is kept at 80°C, and the reaction is performed for 24 hours;

S4. After the reaction is completed, water is removed, and it is put into a vacuum drying oven at 105° C. for drying and activation for 12 hours to obtain double hydrogenated tallow methyl benzyl ammonium chloride modified nano-silica.

Example 2:

The raw materials used in the high viscosity emulsified asphalt are as follows:

Hard petroleum asphalt 55wt%, SBS latex 3wt%, rubber powder dispersion 4wt%, double hydrogenated tallow methyl benzyl ammonium chloride modified nano-silica 0.5wt%, methyl glucoside polyoxyethylene ether two oil Acid 1.5wt%, hydrochloric acid 0.4wt%, water 36.6wt%.

The preparation method of high viscosity emulsified asphalt is as follows:

1. First, add hydrochloric acid to water at room temperature, adjust the pH of the water to about 2±0.5, then heat it to 85°C, keep the temperature, and slowly add dihydrogenated tallow methyl benzyl chloride under stirring Ammonium modified nano-silicon dioxide, methyl glucoside polyoxyethylene ether dioleate, continue to stir for 30 minutes, add hydrochloric acid to adjust the pH of the solution to about 2±0.5 to obtain soap liquid, and then cool it in a natural state Set aside to 55°C.

2. Heat the hard bitumen to 160℃ for standby use;

3. First heat the colloid mill head to 110℃, the asphalt pipeline to 160℃, and the soap liquid pipeline temperature to 55℃. Turn on the emulsified asphalt colloid mill, turn on the asphalt pump and the soap liquid pump, in the self-circulation state, adjust the pressure of the asphalt pipeline and the soap liquid pipeline to 0.25Mpa and 0.15Mpa respectively, and adjust the outlet pressure of the colloid mill to 0.2MPa. At the same time, the emulsified asphalt heat exchange device is turned on, and the cooling water temperature is maintained at about 20 °C. Finally, the soap liquid and the asphalt are pumped to the colloid mill successively, grinded by the colloid mill, and the hard emulsified asphalt is obtained after heat exchange and cold cutting.

4. Add SBS latex and rubber powder dispersion into hard emulsified asphalt at room temperature and under stirring state to pre-disperse the emulsion, and the stirring time is 30min. At the same time, the power supply of the entire system of the colloid mill is turned off, the temperature of the pipeline and the grinding head of the colloid mill return to room temperature, and the pressure of the pipeline returns to atmospheric pressure. Then add the pre-dispersed emulsion to the colloid mill asphalt tank, open the asphalt pump for self-circulation, adjust the asphalt pipeline pressure to 0.15MPa, open the colloid mill (the grinding head is heated off, the colloid mill outlet pressure is atmospheric pressure, and the heat exchange device is closed), and the The pre-dispersed emulsion is pumped to a colloid mill, and after being ground by the colloid mill, a high-viscosity emulsified asphalt is obtained.

Example 3:

The raw materials used in the high-viscosity emulsified asphalt are as follows: hard petroleum asphalt 55wt%, SBS latex 3wt%, rubber powder dispersion 4wt%, double hydrogenated tallow methyl benzyl ammonium chloride modified nano-silica 1.0wt% , methyl glucoside polyoxyethylene ether dioleate 1.5wt%, hydrochloric acid 0.5wt%, water 35wt%.

The preparation method of the high-viscosity emulsified asphalt in this example is the same as that in Example 2.

Example 4:

The raw materials used in the high-viscosity emulsified asphalt are as follows: hard petroleum asphalt 55wt%, SBS latex 3wt%, rubber powder dispersion 4wt%, double hydrogenated tallow methyl benzyl ammonium chloride modified nano-silica 1.5wt% , methyl glucoside polyoxyethylene ether dioleate 1.5wt%, hydrochloric acid 0.6wt%, water 34.4wt%.

The preparation method of the high-viscosity emulsified asphalt in this example is the same as that in Example 2.

Example 5:

The raw materials used in the high viscosity emulsified asphalt are as follows: hard petroleum asphalt 55wt%, SBS latex 3wt%, rubber powder dispersion 2wt%, double hydrogenated tallow methyl benzyl ammonium chloride modified nano-silica 1.0wt% , methyl glucoside polyoxyethylene ether dioleate 1.5wt%, hydrochloric acid 0.5wt%, water 39wt%.

The preparation method of the high-viscosity emulsified asphalt in this example is the same as that in Example 2.

Example 6:

The raw materials used in the high-viscosity emulsified asphalt are as follows: hard petroleum asphalt 55wt%, SBS latex 3wt%, rubber powder dispersion 6wt%, double hydrogenated tallow methyl benzyl ammonium chloride modified nano-silica 1.0wt% , methyl glucoside polyoxyethylene ether dioleate 1.5wt%, hydrochloric acid 0.5wt%, water 33wt%.

The preparation method of the high-viscosity emulsified asphalt in this example is the same as that in Example 2.

Example 7:

The raw materials used in the high-viscosity emulsified asphalt are as follows: hard petroleum asphalt 55wt%, SBS latex 3wt%, rubber powder dispersion 8wt%, double hydrogenated tallow methyl benzyl ammonium chloride modified nano-silica 1.0wt% , methyl glucoside polyoxyethylene ether dioleate 1.5wt%, hydrochloric acid 0.5wt%, water 31wt%.

The preparation method of the high-viscosity emulsified asphalt in this example is the same as that in Example 2.

Example 8:

The raw materials used in the high viscosity emulsified asphalt are as follows: hard petroleum asphalt 55wt%, SBS latex 4wt%, rubber powder dispersion 4wt%, double hydrogenated tallow methyl benzyl ammonium chloride modified nano-silica 1.0wt% , methyl glucoside polyoxyethylene ether dioleate 1.5wt%, hydrochloric acid 0.5wt%, water 34wt%.

The preparation method of the high-viscosity emulsified asphalt in this example is the same as that in Example 2.

Comparative Example 1:

The raw materials used in the high-viscosity emulsified asphalt are as follows: hard petroleum asphalt 55wt%, SBS latex 3wt%, rubber powder dispersion 4wt%, methyl glucoside polyoxyethylene ether dioleate 2.5wt%, hydrochloric acid 0.5wt%, Water 35wt%.

The preparation method of the high-viscosity emulsified asphalt of this comparative example is the same as that of Example 2, except that the modified nano-silicon dioxide is not added with dihydrogenated tallow methyl benzyl ammonium chloride.

Comparative Example 2:

The raw materials used in the high-viscosity emulsified asphalt are as follows: 55wt% of hard petroleum asphalt, 3wt% of SBS latex, 4wt% of rubber powder dispersion, 2.5wt% of double hydrogenated tallow methyl benzyl ammonium chloride modified nano-silica, Hydrochloric acid 0.5wt%, water 35wt%.

The preparation method of the high-viscosity emulsified asphalt of this comparative example is the same as that of Example 2, except that methyl glucoside polyoxyethylene ether dioleate is not added.

Comparative Example 3:

The raw materials used in the high-viscosity emulsified asphalt are as follows: hard petroleum asphalt 55wt%, SBS latex 7wt%, dihydrogenated tallow methyl benzyl ammonium chloride modified nano-silica 1.0wt%, methyl glucoside polyoxyethylene Ether dioleate 1.5wt%, hydrochloric acid 0.5wt%, water 35wt%.

The preparation method of the high-viscosity emulsified asphalt of this comparative example is the same as that of Example 2, except that the rubber powder dispersion liquid is not added.

Comparative Example 4:

The raw materials used in the high-viscosity asphalt are as follows: 55 wt% of hard petroleum asphalt, 7 wt% of rubber powder dispersion, 1.0 wt% of double hydrogenated tallow methyl benzyl ammonium chloride modified nano-silica, methyl glucoside polyoxygen Vinyl ether dioleate 1.5wt%, hydrochloric acid 0.5wt%, water 35wt%.

The preparation method of the high-viscosity asphalt of this comparative example is the same as that of Example 2, except that SBS latex is not added.

Comparative Example 5:

The raw materials used in the high-viscosity asphalt are as follows: hard petroleum asphalt 60wt%, dihydrogenated tallow methyl benzyl ammonium chloride modified nano-silica 1.0wt%, methyl glucoside polyoxyethylene ether dioleate 1.5wt%, hydrochloric acid 0.5wt%, water 37wt%.

The preparation method of the high-viscosity asphalt of this comparative example is the same as the steps 1-3 of Example 2, except that SBS latex and rubber powder dispersion are not added.

Comparative Example 6:

The raw materials used for the high-viscosity asphalt are as follows: AH-70 asphalt 60wt%, dihydrogenated tallow methyl benzyl ammonium chloride modified nano-silica 1.0wt%, methyl glucoside polyoxyethylene ether dioleate 1.5 wt%, hydrochloric acid 0.5wt%, water 37wt%.

The steps of the preparation method of the high-viscosity asphalt of this comparative example are the same as the steps 1-3 of Example 2, except that: (1) AH-70 asphalt is used instead of hard petroleum asphalt; (2) in the third step, the asphalt pipeline is heated to 135 ℃, the outlet pressure of the colloid mill is atmospheric pressure; (3) SBS latex and rubber powder dispersion are not added.

The AH-70 asphalt used is from the same manufacturer as the hard petroleum asphalt, and the oil source for producing the asphalt is the same. The basic physical properties of AH-70 asphalt are as follows: Penetration 68 0.1mm, softening point 46.5℃, ductility at 15℃＞ 100cm.

Comparative Example 7:

The raw materials used in the high-viscosity asphalt are as follows: SBS modified asphalt 60wt%, dihydrogenated tallow methyl benzyl ammonium chloride modified nano-silica 1.0wt%, methyl glucoside polyoxyethylene ether dioleate 1.5 wt% wt%, hydrochloric acid 0.5wt%, water 37wt%.

The preparation method of the high-viscosity asphalt of this comparative example is the same as steps 1-3 of Example 2, except that (1) SBS modified asphalt is used instead of hard petroleum asphalt; (2) SBS latex and rubber powder dispersion are not added.

The adopted SBS modified asphalt is composed of AH-70 asphalt and SBS, wherein the content of SBS is 4.0 wt% of the AH-70 asphalt. The AH-70 asphalt was the same as that of Comparative Example 6.

Test description:

In addition to the conventional performance indicators such as penetration, softening point, and ductility, rotational viscometer, dynamic shear rheometer (DSR), and trabecular bending rheometer (BBR) were used to determine the high-temperature properties and low-temperature properties of high-viscosity emulsified asphalt. performance, durability, etc. Among them, the viscosity obtained by the rotational viscometer test, the rutting factor G*/sinδ measured by DSR, and the softening point can be used to characterize the high temperature performance of asphalt. The higher the softening point, the higher the viscosity, and the greater the rutting factor G*/sinδ. , the better the high temperature anti-rutting performance of asphalt. The creep stiffness S and creep stiffness change rate m obtained by the BBR test, as well as the ductility (5°C) can be used to characterize the low temperature performance of the asphalt. The larger it is, the better the low temperature performance of the asphalt. The strain recovery rate R and the non-recoverable creep compliance J _nr obtained by the DSR test, as well as the elastic recovery rate can be used to characterize the durability _of asphalt. the better.

The evaluation of wheel sticking performance is mainly by testing the length of asphalt remaining on the surface of the wheel after the wheel has passed through a certain length of substrates with different adhesion layer materials on the coating film, and then calculating the wheel sticking rate to characterize it. The bigger it is, the more serious the material sticks to the wheel.

The shear strength and bond strength were used to evaluate the bonding properties of high-viscosity emulsified asphalt. The strength test process is as follows: Two identical rutting specimens were prepared using a wheel forming machine, and the experimental emulsified asphalt was evenly spread on one On the surface of the rutted specimen, and then put another specimen on the side where the asphalt is spread to prepare a rutted specimen, and finally use a coring machine to take samples to obtain a strength test specimen.

The emulsified asphalts obtained in Examples 2-8 and Comparative Examples 1-7 were detected by the above method, and the detection results are shown in Table 1 and Table 2.

Table 1 Performance index of emulsified asphalt

Table 2 Performance index of emulsified asphalt

It should be noted that the SBS modified asphalt emulsified in Comparative Example 7 has excellent high and low temperature performance and durability, and is the most widely used modified asphalt material in the road field, especially for high-grade pavements.

It can be seen from the above table that the demulsification speed of the emulsified asphalt of all the examples is fast cracking, and the storage stability meets the 1d storage stability specified in the "Technical Specification for Highway Asphalt Pavement Construction" (JTGF40-2004), and the storage stability is not greater than 1, 5d storage. The stability is not greater than the requirement of 5, which is the beneficial effect produced by the technical solution provided by the present invention. By comparison, it is found that the storage stability of Example 1, Comparative Example 1 and Comparative Example 2 is worse than that of other examples and comparative examples, indicating that simply using double hydrogenated tallow methyl benzyl ammonium chloride to modify nano-silica, None of the methyl glucoside polyoxyethylene ether dioleate can achieve the desired effect, and reducing the dosage of dihydrogenated tallow methyl benzyl ammonium chloride modified nano-silica will also be detrimental to storage stability influences.

It can be seen from the examples and comparative examples that the example after adding SBS and rubber powder is compared with comparative example 5. Penetration, softening point, ductility, viscosity, and rutting factor were all significantly improved, the creep stiffness decreased s, and the creep stiffness change rate m increased, showing good high temperature, performance, and elastic recovery rate and strain recovery rate. (R) increases and the irrecoverable creep compliance decreases, showing very good viscoelastic properties. At the same time, the addition of SBS has obvious advantages in the improvement of low temperature performance, while the rubber powder has obvious advantages in high temperature performance and viscoelastic improvement.

In addition, it can also be seen from the comparative examples and examples that, compared with AH-70 base asphalt and SBS modified asphalt, the embodiment of the present invention has a significantly lower stickiness ratio, and a significant increase in shear strength and bond strength. Moreover, rubber powder has more obvious advantages in reducing the stickiness rate.

To sum up, the high-temperature performance and viscoelastic performance of the high-viscosity emulsified asphalt prepared in the embodiment of the present invention are higher than those of the commonly used SBS modified asphalt, and the low-temperature performance is equivalent to it, and meets the requirements of the specification; and bond strength are better than SBS modified asphalt. In addition, the cost of the rubber powder used in this embodiment is lower than that of base asphalt, hard asphalt and SBS, so the overall cost of the high-viscosity asphalt in this embodiment is lower than that of SBS modified asphalt.

Example 9:

1. Preparation of high viscosity emulsified asphalt

The high-viscosity emulsified asphalt prepared by the method described in Example 3.

2. Preparation of embedded warm mix asphalt

(1) Preparation of warm mix high viscosity modified asphalt

The warm-mix high-viscosity modified asphalt used in this example is obtained by mixing AH-70 asphalt, high-viscosity asphalt modifier, sulfur stabilizer, extraction oil and warm-mix agent.

The mass percentages of each raw material are:

in:

In terms of mass percentage, the high-viscosity asphalt modifier is made of 10% of C9 petroleum resin, 6% of polystyrene-polybutadiene block copolymer SBS, 80% of rubber powder, 2% of solid rosin and 2% of talcum powder. have to. The raw materials such as C9 petroleum resin particles, granular SBS modifier, powdered solid rosin, rubber powder particles and talc powder are added to the pulverizer for pulverization, and premixed uniformly to obtain mixed solid powder. The mixed solid powder is injected into the preheated (180°C) twin-screw extruder, and the extruded strip mixture enters the cold water water for cooling, and is cut and sieved by the granulator to form granular high viscosity. Finished asphalt modifier.

The warm-mixing agent is a palmitic acid imidazoline warm-mixing agent, which is prepared from palmitic acid and tetraethylenepentamine by amidation and cyclization, and the reaction raw materials palm oleic acid and tetraethylenepentamine are prepared according to the quality of 1:1.2 The ratio was added into a three-necked glass flask, a certain amount of xylene was added as a water-carrying agent (30% of the total mass of palmitoleic acid and tetraethylene pentamine), the temperature was gradually raised and refluxed under magnetic stirring, and reacted at a reaction temperature of 150 ° C for 6 Hours. In this process, the carboxylic acid group in palmitoleic acid undergoes amidation reaction with the amine group in tetraethylenepentamine. After the reaction was completed, the excess xylene was distilled off, then the flask was evacuated to a vacuum degree of 0.096 MPa, and the temperature was raised to 260° C. under stirring to carry out cyclization reaction for 4 hours to obtain a crude warm stirring agent. The crude product was subjected to rotary evaporation at 60° C. for 1 h to remove water and solvent, recrystallized with acetone for three times, and vacuum dried for 12 h to obtain an imidazoline palmitate warm-mixing agent product.

The technical properties of the obtained warm-mix high-viscosity asphalt are shown in Table 3.

Table 3 Performance index of warm mix high viscosity asphalt

Performance Example 2 Penetration/0.1mm 36 Softening point/℃ 81.2 Ductility (5℃)/cm 21.3 Viscosity(60℃)/Pa·s 34382 Viscosity (135℃)/Pa s 6.928 Elastic recovery rate/% 94.6

(2) Preparation of embedded-solid warm-mix high-viscosity modified asphalt mixture

1. The composition of the embedded-solid warm-mix high-viscosity modified asphalt mixture in this example is shown in Table 4.

Table 4 Composition of Mixtures

The filler is composed of 99% limestone powder and 1% slaked lime.

The ore gradation of the embedded modified asphalt mixture prepared according to the composition ratio shown in Table 4 is shown in Table 5.

Table 5 Mineral gradation of embedded modified asphalt mixture

2. Preparation method of embedded-solid warm-mix high-viscosity modified asphalt mixture:

According to the proportions described in Table 4, weigh the fine aggregate, 5mm-7mm chopped untwisted aggregate fibers and coarse aggregate and mix for 15s, then add warm-mixed high-viscosity modified asphalt and mix for 20s, and finally add filler and mix for 20s to get the embedded Solid Asphalt Mixtures. The mixture was compacted under the conditions of a unit pressure of 600KPa, a rotation angle of 1.25°, a rotation speed of 30r/min, and a set number of rotary compactions of 100 times. The volume index of the asphalt mixture after compaction was tested. As shown in Table 6.

Table 6 Volume index of embedded asphalt mixture

Volume indicator unit Test results void ratio (VV) % 3.8 Mineral clearance ratio (VMA) % 18.9 Asphalt saturation (VFA) % 79.7 Oil film thickness μm 10.6

3. Road performance:

(1) Prepare the embedded warm-mix high-viscosity modified asphalt mixture according to the composition ratio shown in Table 4 and form the test piece, and test its various road performance indicators. The test results are shown in Table 7.

Table 7 Test results of road performance indexes of embedded warm-mix high-viscosity modified asphalt mixture

Test items unit Test results Binder loss in asphalt leakage test % 0.03 Marshall Residue Stability of Immersion in Water % 92.4 Freeze-thaw splitting strength ratio % 90.4 Rutting test dynamic stability times/mm 8860 low temperature bending failure strain με 3380 tectonic depth mm 0.87 Pendulum friction coefficient / 73.3

(2) Bonding ability

Using 0.6kg/m2 high ^- viscosity emulsified asphalt as the sticky oil, the AC-13 original road surface was overlaid with a 2.5cm thickness of the embedded warm-mix high-viscosity modified asphalt mixture shown in Table 3, and the oblique shear test was used. (45°) The measured interlaminar shear strength at 25°C is 2.83MPa, and the interlaminar bond strength at 25°C obtained by the pull test is 1.62MPa.

As a comparison, the high-viscosity emulsified asphalt was replaced with ordinary emulsified asphalt and SBR latex modified emulsified asphalt respectively. For the viscosity-modified asphalt mixture, the interlaminar shear strength at 25°C measured by the oblique shear test (45°) is 2.35MPa and 2.10MPa respectively, and the interlaminar bond strength at 25°C obtained by the pull-out test is 0.53MPa and 0.45MPa.

It shows that the high-viscosity emulsified asphalt of the present invention is used in combination with the embedded warm-mix high-viscosity modified asphalt mixture, and has higher shear strength and bond strength than the traditional emulsified asphalt.

Example 10:

1. Preparation of high viscosity emulsified asphalt

The high viscosity emulsified asphalt prepared by the method described in Example 6.

2. Preparation of embedded warm mix asphalt

(1) Preparation of warm mix high viscosity modified asphalt

The raw materials and preparation method of the warm-mix high-viscosity modified asphalt are the same as those in Example 9.

(2) Preparation of embedded-solid warm-mix high-viscosity modified asphalt mixture

1. The composition of the embedded solid-type warm-mixed high-viscosity modified asphalt mixture in this example is shown in Table 8.

Table 8 Composition of Mixtures

The filler is composed of 99% limestone powder and 1% slaked lime.

The ore gradation of the embedded modified asphalt mixture prepared according to the composition ratio shown in Table 8 is shown in Table 9.

Table 9 Mineral Gradation of Embedded Modified Asphalt Mixtures

2. Preparation method of embedded-solid warm-mix high-viscosity modified asphalt mixture:

According to the ratio described in Table 8, weigh the fine aggregate, 5mm-7mm chopped untwisted aggregate fibers and coarse aggregate and mix for 15s, then add warm-mixed high-viscosity modified asphalt and mix for 20s, and finally add filler and mix for 20s. Solid Asphalt Mixtures. The obtained mixture was compacted under the conditions of a unit pressure of 600Kpa, a rotation angle of 1.25°, a rotation speed of 30r/min, and the set number of rotary compactions was 100 times, and the volume index test was carried out. The volume of the asphalt mixture after compaction was The indicators are shown in Table 10.

Table 10 Volume index of embedded warm-mix high-viscosity modified asphalt mixture

Volume indicator unit Test results void ratio (VV) % 4.1 Mineral clearance ratio (VMA) % 22.3 Asphalt saturation (VFA) % 81.6 Oil film thickness μm 10.9

3. Road performance:

(1) Prepare the embedded warm-mix high-viscosity modified asphalt mixture according to the composition ratio shown in Table 8 and form the test piece, and test its various road performance indicators. The test results are shown in Table 11.

Table 11 Test results of road performance indexes of embedded warm-mix high-viscosity modified asphalt mixture

Test items unit Test results Binder loss in asphalt leakage test % 0.01 Marshall Residue Stability of Immersion in Water % 93 Freeze-thaw splitting strength ratio % 92.5 Rutting test dynamic stability times/mm 8900 low temperature bending failure strain με 3250 tectonic depth mm 0.89 Pendulum friction coefficient / 74.2

(2) Bonding ability

Using 0.6kg/m2 high ^- viscosity emulsified asphalt as the sticky oil, the AC-13 original pavement was overlaid with 2.5cm thick embedded warm-mix high-viscosity modified asphalt mixture shown in Table 8, and the inclined shear test was used. (45°) The measured interlaminar shear strength at 25°C is 2.57Mpa, and the interlaminar bond strength at 25°C obtained by the pull-out test is 1.54MPa.

The above-mentioned embodiments are only preferred specific embodiments of the present invention, and the usual changes and substitutions made by those skilled in the art within the scope of the technical solutions of the present invention should be included in the protection scope of the present invention.

Claims (10)

1. an ultra-thin wear layer paving method based on high viscosity emulsified asphalt, is characterized in that, comprises: S1. Spread high-viscosity emulsified asphalt on the original road to form a bonding layer, According to the mass percentage, the high viscosity emulsified asphalt is prepared from the following raw materials:

S2. Pave embedded solid warm mix asphalt and compact it. 2. the ultra-thin wear layer paving method based on high viscosity emulsified asphalt according to claim 1, is characterized in that: described double hydrogenated tallow methyl benzyl ammonium chloride modified nano-silica is made of double hydrogenated tallow It is obtained by modifying nano-silica with methyl benzyl ammonium chloride. 3. the ultra-thin wear layer paving method based on high viscosity emulsified asphalt according to claim 1, is characterized in that: the preparation method of described dihydrogenated tallow methyl benzyl ammonium chloride modified nano-silica comprises: : Dissolving 4-6wt% dihydrogenated tallow methyl benzyl ammonium chloride in an aqueous hydrochloric acid solution with a pH value of 2-3 at 75-90 ° C to obtain a solution; adding 18-22wt% nano-silicon dioxide to the water solubility of glycerol and stirring evenly, heating to 75-90°C to obtain b suspension; Mix the a solution and the b suspension according to the mass ratio of 1:(0.8-1.2), and react at 75-90 ° C for 12-36 hours. After the reaction is completed, remove the water, and dry and activate it in a vacuum for 8-16 hours to obtain the obtained solution. Described double hydrogenated tallow methyl benzyl ammonium chloride modified nano-silica. 4. the ultra-thin wear layer paving method based on high-viscosity emulsified asphalt according to claim 1, 2 or 3, is characterized in that: rubber powder dispersion liquid is made up of rubber powder, suspending agent, dispersant and water, rubber powder The mass ratio of , suspending agent, dispersing agent and water is 10:(0.5-1.5):(0.5-1.5):(1-3), and the mass percentage of rubber powder is not less than 70%. 5. The ultra-thin wear layer paving method based on high-viscosity emulsified asphalt according to claim 1, 2 or 3, is characterized in that: the preparation method of high-viscosity emulsified asphalt comprises the following steps: S1. Add double hydrogenated tallow methyl benzyl ammonium chloride modified nano-silica and methyl glucoside polyoxyethylene ether dioleate to 80-90 ° C hydrochloric acid aqueous solution to obtain a pH value of 1-3 the soap solution, and then cooled to 50-60 ℃ in a natural state for use; S2. Heat the hard bitumen to 155-170°C for use; S3. The soap liquid and asphalt are sent to the colloid mill, ground by the colloid mill, and the hard emulsified asphalt is obtained after heat exchange and cooling; S4. SBS latex, rubber powder dispersion, and hard emulsified asphalt are mixed and stirred to obtain a pre-dispersed emulsion; after the pre-dispersed emulsion is ground by a colloid mill, a high-viscosity emulsified asphalt is obtained. 6. The ultra-thin wear layer paving method based on high viscosity emulsified asphalt according to claim 5, is characterized in that: step S3 comprises: S31. Preheat colloid mill grinding head, asphalt pipeline and soap liquid pipeline; S32. Increase the outlet pressure of the asphalt pipeline, the soap liquid pipeline and the colloid mill, wherein the outlet pressure of the colloid mill is adjusted to 0.15-0.25MPa. 7. The ultra-thin wear layer paving method based on high-viscosity emulsified asphalt according to claim 1, characterized in that: in terms of mass percentage, the embedded warm-mix asphalt mixture is composed of a temperature of 5.5%-8.5%. Mixed high viscosity modified asphalt, 0.1%-0.5% 5mm-7mm chopped untwisted polyester fiber, 70%-75% coarse aggregate, 15%-20% fine aggregate and 6%-12 % of filler mixed. 8. The ultra-thin wear layer paving method based on high-viscosity emulsified asphalt according to claim 7, characterized in that: in terms of mass percentage, the warm-mixed high-viscosity modified asphalt is composed of 80%-90% AH- 70% asphalt, 10%-16% high viscosity asphalt modifier, 0.02%-0.04% stabilizer, 0.4%-0.8% compatibilizer, 0.4%-1.0% warm mix agent, The high-viscosity modifier is composed of _C9 petroleum resin, polystyrene-polybutadiene block copolymer SBS, rubber powder, solid rosin and talcum powder; The stabilizer is a sulfur stabilizer; The compatibilizer is an extraction oil; The warm mix agent is an imidazoline palmitate warm mix agent. 9 . The ultra-thin wear layer paving method based on high-viscosity emulsified asphalt according to claim 7 , wherein the coarse aggregate has a nominal maximum particle size of 9.5 mm and a sieve hole pass rate of 4.75 mm less than 5%. 10 . The basalt or/and diabase crushed stone, wherein the content of crushed stone with a particle size of 6.7mm-9.5mm is greater than 65%; The fine aggregate is machine-made sand or stone chips processed by alkaline or neutral stone with a 2.36mm sieve hole passing rate greater than 95% and a 0.075mm sieve hole passing rate less than 8%; The filler includes limestone powder and slaked lime or cement with a content of less than 2%. 10. The ultra-thin wear layer paving method based on high-viscosity emulsified asphalt according to claim 7, is characterized in that: comprises the following construction steps: S1. Clean the original road surface and deal with the disease; S2. Spread 0.3L/m ² -1.2L/m ² high-viscosity emulsified asphalt bonding layer on the original road surface under the condition that the road surface temperature is not lower than 5 ℃; S3. A layer of embedded warm-mixed high-viscosity modified asphalt mixture with a thickness of 1.6cm-3.0cm is laid on the above-mentioned bonding layer, and the paving temperature is 115°C-155°C. S4. Under the condition of 90-145 ℃, the warm-mixed high-viscosity modified asphalt mixture paved in step S3 is rolled, embedded and compacted by a rubber wheel road roller to form a 1.5cm-2.5cm thick road superstructure. Thin wear layer.