阅读说明：本技术 一种直投式增粘再生改性剂及其制备和应用方法 (Direct-vat-set tackifying regenerative modifier and preparation and application methods thereof ) 是由 高立波 孙继伟 金塬上 朱建平 周健楠 王枫成 冯德成 易军艳 白晓燕 于 2020-12-10 设计创作，主要内容包括：一种直投式增粘再生改性剂及其制备和应用方法,属于道路沥青混合料领域,按质量百分比5～26.7％的生物油,4～5％的稳定剂,1～5％的改性增粘液,2.5～20％混合轻质油,6.7～33.3％的SBS改性剂,6.7～41.7％的SIS改性剂,6.7～41.7％的SBR改性剂均匀混合而成,且各组份的质量百分比之和为100％。其制备方法包括：1、制备高效沥青再生剂；2、制备直投式增粘改性剂混合物；3、将制备得到的高效沥青再生剂和直投式增粘改性剂混合物按照质量比混合得到直投式增粘再生改性剂。本发明方法制备的直投式增粘再生改性剂,应用于大比例再生高性能沥青混合料,可以得到各项性能优良的沥青混合料。(A direct-throwing tackifying and regenerating modifier and a preparation and application method thereof belong to the field of road asphalt mixtures, and are prepared by uniformly mixing 5-26.7% by mass of bio-oil, 4-5% by mass of a stabilizer, 1-5% by mass of a modified tackifying liquid, 2.5-20% by mass of mixed light oil, 6.7-33.3% by mass of an SBS modifier, 6.7-41.7% by mass of an SIS modifier and 6.7-41.7% by mass of an SBR modifier, wherein the sum of the mass percentages of the components is 100%. The preparation method comprises the following steps: 1. preparing a high-efficiency asphalt regenerant; 2. preparing a direct-vat set tackifying modifier mixture; 3. and mixing the prepared high-efficiency asphalt regenerant and the direct-vat-set tackifying modifier mixture according to the mass ratio to obtain the direct-vat-set tackifying regenerating modifier. The direct-vat tackifying and regenerating modifier prepared by the method is applied to regenerating high-performance asphalt mixture in a large proportion, and can obtain the asphalt mixture with excellent performances.)

1. A direct-vat tackifying and regenerating modifier is characterized by being prepared by uniformly mixing 5-26.7% of bio-oil, 4-5% of a stabilizer, 1-5% of modified tackifying liquid, 2.5-20% of mixed light oil, 6.7-33.3% of SBS modifier, 6.7-41.7% of SIS modifier and 6.7-41.7% of SBR modifier according to mass percentage, wherein the sum of the mass percentages of the components is 100%;

the bio-oil is a mixture obtained by compounding saturated fatty acid and unsaturated fatty acid according to the mass ratio of 1:1, the stabilizer is trilinear oil, the modified tackifying liquid is liquid rosin or other resin tackifying liquid, and the mixed light oil is a mixture obtained by compounding extract oil and rubber oil according to the mass ratio of 3: 1.

2. The method for preparing the direct vat set forth in claim 1, characterized in that the method comprises the following steps:

(1) preparing a high-efficiency asphalt regenerant:

respectively weighing 80-30% of bio-oil, 4-5% of stabilizer, 1-5% of modified thickening fluid and 15-60% of mixed light oil according to the mass percentage, wherein the total amount is 100%; adding all the weighed materials into a stirring kettle, stirring uniformly, and keeping the temperature at room temperature or 40-60 ℃ to obtain the high-efficiency asphalt regenerant;

(2) preparing a direct vat set tackifying modifier mixture:

respectively weighing 10-40% of SBS modifier, 10-50% of SIS modifier, 10-50% of SBR modifier, 4-5% of stabilizer and 1-5% of modified thickening fluid according to mass percentage, wherein the total amount is 100%; putting all the weighed materials into a high-speed mixer at room temperature, and stirring uniformly to obtain a direct-vat-set tackifying modifier mixture;

(3) adding the prepared mixture of the efficient asphalt regenerant and the direct-vat-set tackifying modifier into a double-screw extruder according to the mass ratio of 1 (2-5) for extrusion forming, and then granulating, wherein the working temperature of the double-screw extruder is kept at 170-190 ℃ to obtain the direct-vat-set tackifying regenerant modifier.

3. The preparation method of the direct vat set tackifying regeneration modifier according to claim 2, wherein in the step, the bio-oil is a mixture obtained by compounding saturated fatty acid and unsaturated fatty acid according to a mass ratio of 1: 1; the stabilizer is trillium oil; the modified thickening fluid is liquid rosin or other resin thickening fluids; the mixed light oil is a mixture obtained by compounding extract oil and rubber oil according to the mass ratio of 3: 1.

4. The application method of the direct vat set tackifying recycling modifier in the large-scale recycling of high-performance asphalt mixture according to claim 1 is characterized by comprising the following steps in sequence:

(1) dividing the old RAP material into three grades of materials with the particle sizes of 0-5mm, 5-10mm and 10-20mm, respectively weighing 20-30% of RAP material with the particle size of 10-20mm, 20-30% of RAP material with the particle size of 5-10mm and 25-35% of RAP material with the particle size of 0-5mm according to mass percent, and preheating for later use at the preheating temperature of 120-140 ℃;

(2) weighing new aggregate according to the mass ratio of the old RAP material to the new aggregate of 70:30, and heating to 190-200 ℃ for later use; the new aggregate is composed of new broken stones and new machine-made sand in a mass ratio of 4: 1;

(3) weighing new asphalt according to the mass ratio of (the old RAP material and the new aggregate) to (100) (2-5), and heating to 150-170 ℃ for later use; the new asphalt is 70#, 90# or 110# base asphalt;

(4) adding all the preheated old RAP materials into a mixing pot, adding the direct-vat tackifying and regenerating modifier prepared by the method according to the mass ratio of (old RAP materials + new aggregates) to (0.3-0.5) 100, raising the temperature of the mixing pot to 160-180 ℃, and stirring for 60 s;

(5) pouring the preheated new aggregate into a stirring pot, and continuously stirring for 60s at 160-180 ℃;

(6) adding preheated new asphalt, continuously keeping the temperature of 160-180 ℃, stirring for 60s, and discharging to obtain a large-proportion regenerated high-performance asphalt mixture.

Technical Field

The invention belongs to the field of road asphalt mixtures, and particularly relates to a direct-vat-set tackifying and regenerating modifier and a preparation method and an application method thereof.

Background

In China, the wide-range construction of asphalt concrete pavements begins from the 80 th of the 20 th century, and the common service life of roads is 10-15 years. At the present stage, a large number of roads have reached the service life, about 12% of high-grade roads in the country need to be overhauled every year, and the conservative estimation is 220 ten thousand tons of asphalt pavement waste materials every year. In addition, environmental problems concerned by people are not ignored, and meanwhile, the nonrenewable resource of asphalt needs to be more precious, so that whether the old materials can be recycled to the maximum extent becomes a popular research subject in the industry.

Disclosure of Invention

Aiming at the defects in the prior art, the invention provides a direct-vat-set tackifying and regenerating modifier for large-proportion hot-regenerated asphalt concrete and a preparation and application method thereof.

The direct-vat tackifying and regenerating modifier is prepared by uniformly mixing 5-26.7% of bio-oil, 4-5% of a stabilizer, 1-5% of modified tackifying liquid, 2.5-20% of mixed light oil, 6.7-33.3% of SBS modifier, 6.7-41.7% of SIS modifier and 6.7-41.7% of SBR modifier by mass percent, wherein the sum of the mass percentages of the components is 100%;

the bio-oil is a mixture obtained by compounding saturated fatty acid and unsaturated fatty acid according to the mass ratio of 1:1, the stabilizer is trilinear oil, the modified tackifying liquid is liquid rosin or other resin tackifying liquid, and the mixed light oil is a mixture obtained by compounding extract oil and rubber oil according to the mass ratio of 3: 1.

The invention provides a preparation method of a direct-vat-set tackifying regenerative modifier, which comprises the following steps in sequence:

(1) preparing a high-efficiency asphalt regenerant:

respectively weighing 80-30% of bio-oil, 4-5% of stabilizer, 1-5% of modified thickening fluid and 15-60% of mixed light oil according to the mass percentage, wherein the total amount is 100%; adding all the weighed materials into a stirring kettle, stirring uniformly, and keeping the temperature at room temperature or 40-60 ℃ to obtain the high-efficiency asphalt regenerant;

(2) preparing a direct vat set tackifying modifier mixture:

respectively weighing 10-40% of SBS modifier, 10-50% of SIS modifier, 10-50% of SBR modifier, 4-5% of stabilizer and 1-5% of modified thickening fluid according to mass percentage, wherein the total amount is 100%; putting all the weighed materials into a high-speed mixer at room temperature, and stirring uniformly to obtain a direct-vat-set tackifying modifier mixture;

(3) adding the prepared mixture of the efficient asphalt regenerant and the direct-vat-set tackifying modifier into a double-screw extruder according to the mass ratio of 1 (2-5) for extrusion forming, and then granulating by a granulator, wherein the working temperature of the double-screw extruder is kept at 170-190 ℃ to obtain the direct-vat-set tackifying regenerant modifier.

The preparation method of the direct vat set tackifying regenerative modifier comprises the following steps:

in the step (1), the biological oil is a mixture obtained by compounding saturated fatty acid and unsaturated fatty acid according to a mass ratio of 1: 1. The efficient asphalt regenerant and the preparation method thereof adopt the method in CN202010678945.4 efficient asphalt regenerant for large-proportion hot recycled asphalt concrete and the preparation method thereof.

In the step (1) and the step (2), the stabilizing agent is trillium oil; the modified thickening fluid is liquid rosin or other resin thickening fluids; the mixed light oil is a mixture obtained by compounding extract oil and rubber oil according to the mass ratio of 3: 1.

The direct-vat tackifying and regenerating modifier is applied to the preparation of a large-proportion regenerated high-performance asphalt mixture, wherein the asphalt mixture consists of an old RAP material, new aggregates, new asphalt and the direct-vat tackifying and regenerating modifier, and the new asphalt is 70#, 90# or 110# matrix asphalt; the new aggregate is composed of new crushed stone and new machine-made sand.

The RAP old material is obtained by finely separating the old material after milling the pavement, the old material after milling the pavement is a milling material for the middle and lower layers of the old pavement, and the RAP old material is prepared by a method in CN202010758112.9 fine separation and recycling system and process for an asphalt pavement milling material.

The application method of the direct-vat tackifying and regenerating modifier in the large-proportion regeneration of high-performance asphalt mixture comprises the following steps:

(1) dividing the old RAP material into three grades of materials with the particle sizes of 0-5mm, 5-10mm and 10-20mm, respectively weighing 20-30% of RAP material with the particle size of 10-20mm, 20-30% of RAP material with the particle size of 5-10mm and 25-35% of RAP material with the particle size of 0-5mm according to mass percent, and preheating for later use at the preheating temperature of 120-140 ℃;

(2) weighing new aggregate according to the mass ratio of the old RAP material to the new aggregate of 70:30, and heating to 190-200 ℃ for later use; the new aggregate is composed of new broken stones and new machine-made sand in a mass ratio of 4: 1;

(3) weighing new asphalt according to the mass ratio of (the old RAP material and the new aggregate) to (100) (2-5), and heating to 150-170 ℃ for later use;

(4) adding all the preheated old RAP materials into a mixing pot, adding the direct-vat tackifying and regenerating modifier prepared by the method according to the mass ratio of (old RAP materials + new aggregates) to (0.3-0.5) 100, raising the temperature of the mixing pot to 160-180 ℃, and stirring for 60 s;

(5) pouring the preheated new aggregate into a stirring pot, and continuously stirring for 60s at 160-180 ℃;

(6) adding preheated new asphalt, continuously keeping the temperature of 160-180 ℃, stirring for 60s, and discharging to obtain a large-proportion regenerated high-performance asphalt mixture.

The invention has the advantages that:

the direct-vat tackifying and regenerating modifier integrating regeneration, tackifying and modification functions is applied to a large-proportion (the mixing proportion of an old RAP material is more than 70%) regenerated asphalt mixture, can recover the performance of old asphalt in a milling reclaimed material of an asphalt pavement, improve the viscosity of asphalt, effectively improve the bonding capacity between the asphalt and stone materials, improve the high-temperature rutting resistance, the low-temperature cracking resistance, the fatigue resistance and the water stability of the asphalt mixture, and can regenerate the old material of a common asphalt mixture into high-performance modified or high-modulus regenerated asphalt concrete. The direct-vat-set tackifying and regenerating modifier obtained by the method is solid particles at normal temperature, and the addition mode is a direct-vat-set mode, so that the operation and the addition in the practical application process are convenient.

Detailed Description

A direct vat set tackifying regeneration modifier is prepared by uniformly mixing 8% of bio-oil, 4.8% of trilinear oil, 4.2% of liquid rosin, 11% of mixed light oil, 16% of SBS modifier, 40% of SIS modifier and 16% of SBR modifier according to mass percentage; wherein the biological oil is a mixture obtained by compounding stearic acid and oleic acid according to the mass ratio of 1: 1; the mixed light oil is a mixture obtained by compounding extract oil and rubber oil according to the mass ratio of 3: 1.

The preparation method of the direct vat set tackifying regenerative modifier comprises the following specific operation steps:

(1) preparing a high-efficiency asphalt regenerant:

respectively weighing 40% of bio-oil, 4% of trilinear oil, 1% of liquid rosin and 55% of mixed light oil according to the mass percent, wherein the total is 100%; the biological oil is a mixture obtained by compounding stearic acid and oleic acid according to the mass ratio of 1: 1; the mixed light oil is a mixture obtained by compounding extract oil and rubber oil according to the mass ratio of 3: 1;

adding all the weighed materials into a stirring kettle, and stirring uniformly, wherein the temperature is kept at 40 ℃ to obtain the high-efficiency asphalt regenerant;

(2) preparing a direct vat set tackifying modifier mixture:

respectively weighing 20% of SBS modifier, 50% of SIS modifier, 20% of SBR modifier, 5% of trilinear oil and 5% of liquid rosin according to the mass percent, wherein the total amount is 100%; putting all the weighed materials into a high-speed mixer at room temperature, and stirring uniformly to obtain a direct-vat-set tackifying modifier mixture;

(3) adding the prepared mixture of the efficient asphalt regenerant and the direct-vat-set tackifying modifying agent into a double-screw extruder according to the mass ratio of 1:4 for extrusion, and granulating in a granulator, wherein the working temperature of the double-screw extruder is kept at 170-190 ℃ to obtain the direct-vat-set tackifying regenerating modifying agent.

The direct vat set tackifying and regenerating modifier prepared in the embodiment is applied to the preparation of a large-proportion regenerated high-performance asphalt mixture, and the specific process is as follows:

(1) after finely separating the old RAP material, weighing 21% of old RAP material with the particle size of 10-20mm, 19% of old RAP material with the particle size of 5-10mm and 30% of old RAP material with the particle size of 0-5mm according to the mass percentage, and preheating for later use at the preheating temperature of 130 ℃;

(2) weighing new aggregate according to the mass ratio of the old RAP material to the new aggregate of 70:30, and heating to 190 ℃ for later use; the new aggregate is composed of new broken stones with the grain diameter of 16-19mm, new broken stones with the grain diameter of 13.2-16mm and new machine-made sand with the grain diameter of 2.36-4.75mm according to the mass ratio of 8:4: 3;

(3) weighing new asphalt according to the mass ratio of (the old RAP material and the new aggregate) to the new asphalt being 100:2.47, and heating to 150 ℃ for later use;

(4) adding all the preheated old RAP materials into a stirring pot, adding the direct-vat tackifying and regenerating modifier prepared by the method according to the mass ratio of (the old RAP materials and the new aggregate) to the direct-vat tackifying and regenerating modifier of 100:0.4, raising the temperature of the stirring pot to 160 ℃, and stirring for 60 s;

(5) pouring the preheated new aggregate into a stirring pot, and continuously keeping the temperature at 160 ℃ and stirring for 60 s;

(6) adding preheated new asphalt, keeping the temperature at 160 ℃, stirring for 60s, discharging, and controlling the discharging temperature at 160-180 ℃.

The screening results after the extraction of the old RAP material are finely separated are shown in Table 1; the gradation of the large-proportion recycled high-performance asphalt mixture is shown in table 2; the results of several asphalt mixture performance tests are shown in table 3, wherein the results of this example are a large-scale recycled high-performance asphalt mixture with a direct-vat-set tackifying and recycling modifier added in the specific embodiment of the present invention.

TABLE 1 screening results after RAP extraction for Fine separation

TABLE 2 Large-scale recycled high-performance asphalt mixture synthetic gradation

TABLE 3 test results of asphalt mixture performance

As can be seen from the data in Table 3, the mechanical properties of the large-proportion recycled high-performance asphalt mixture added with the direct-vat tackifying recycling modifier can meet the technical requirements of the field on brand new matrix asphalt, modified asphalt and high-modulus asphalt mixtures.

Fatigue damage is one of the most main failure modes of asphalt concrete pavements, and in order to ensure that the asphalt pavements have good usability and durability, the asphalt pavement design methods of various countries in the world all use the pavement fatigue property as a basic design principle. At present, most national pavement design methods take fatigue as an important design index of pavement structures. In the embodiment, a four-point bending trabecula fatigue testing machine is adopted, and the load control mode is strain control. The invention aims at brand new AC-20 matrix asphalt, high modulus AC-20 asphalt, SBS modified AC-20 matrix asphalt, and AC-20 matrix asphalt (AC-20 (70+0.4) for short) added with 70 parts of RAP old material and 0.4 part of direct vat set tackifying regeneration modifier prepared by the embodiment of the invention, and the specific results are shown in Table 4.

TABLE 4 fatigue test results for bituminous mixtures

From the fatigue result and the fatigue equation, the fatigue performance of the asphalt mixture after the direct-vat tackifying and regenerating modifier is added is superior to that of other asphalt mixtures. The fatigue performance of the asphalt mixture added with the direct vat set tackifying regeneration modifier prepared by the embodiment of the invention is obviously improved, even higher than that of brand new AC-20 matrix asphalt, which shows that the regeneration modifier is beneficial to improving the fatigue performance of the regenerated asphalt mixture.

The bio-oil adopted by the direct vat set tackifying regeneration modifier is a mixture of saturated fatty acid and unsaturated fatty acid, and the adopted modifiers comprise SBS modifier, SIS modifier and SBR modifier. During the high-temperature heating and stirring process for preparing the direct-vat tackifying and regenerating modifier, the modifier is firstly melted and then entwined among molecular chains, even cross-linking reaction can be generated, and the molecular chains of the adopted unsaturated fatty acid and saturated fatty acid contain unsaturated bonds and polar carboxyl groups, and the reaction can be generated with the molecular chains of the modifier. Therefore, the asphalt mixture of the direct-vat tackifying and regenerating modifier prepared by the method has excellent performances.

According to the detection results, the direct-vat-set tackifying and regenerating modifier is applied to a large-proportion (more than 70% of the mixing proportion of the old RAP material) regenerated asphalt mixture, can recover the performance of the old asphalt in the reclaimed material (RAP), improve the viscosity of the asphalt, effectively improve the bonding capacity between the asphalt and stone materials, improve the high and low temperature performance of the asphalt mixture, and can regenerate the old common asphalt mixture into high-performance modified or high-modulus regenerated asphalt concrete.