阅读说明：本技术 一种sbs改性沥青混凝土及其制备方法 (SBS modified asphalt concrete and preparation method thereof ) 是由 蒋文中 胡明文 卢微 孙星星 于 2020-06-03 设计创作，主要内容包括：本发明涉及一种SBS改性沥青混凝土及其制备方法,涉及路面铺设材料的技术领域,SBS改性沥青混凝土包括以下重量份的组分：粗细集料300～500份、沥青15～30份、SBS 1.5～3.5份以及交联剂粒子0.5～1.5份；交联剂粒子包括以下重量份的组分：液体古马隆树脂65～85份、硫磺15～25份、三氯甲烷5～10份以及有机锡稳定剂1～2份；制备方法包括以下步骤：S1.先对沥青进行预热处理,将沥青加热至软化状态；S2.将SBS投入经过S1处理后的沥青中,将两者搅拌均匀,对沥青进行改性,制得SBS改性沥青；S3.向SBS改性沥青中加入粗细集料与交联剂粒子,在40r/min的转速下将混合料搅拌均匀,制得成品。本发明制备的混凝土具有良好的稳定性,解决了现有技术中其稳定性不佳的问题。(The invention relates to SBS modified asphalt concrete and a preparation method thereof, relating to the technical field of pavement paving materials, wherein the SBS modified asphalt concrete comprises the following components in parts by weight: 300-500 parts of coarse and fine aggregate, 15-30 parts of asphalt, 1.5-3.5 parts of SBS and 0.5-1.5 parts of cross-linking agent particles; the cross-linking agent particles comprise the following components in parts by weight: 65-85 parts of liquid coumarone resin, 15-25 parts of sulfur, 5-10 parts of trichloromethane and 1-2 parts of organic tin stabilizer; the preparation method comprises the following steps: s1, preheating asphalt, and heating the asphalt to a softening state; s2, adding SBS into the asphalt treated by S1, uniformly stirring the two, and modifying the asphalt to obtain SBS modified asphalt; s3, adding coarse and fine aggregates and cross-linking agent particles into SBS modified asphalt, and uniformly stirring the mixture at the rotating speed of 40r/min to obtain a finished product. The concrete prepared by the invention has good stability, and solves the problem of poor stability in the prior art.)

1. The SBS modified asphalt concrete comprises the following components in parts by weight: 300-500 parts of coarse and fine aggregate, 15-30 parts of asphalt, 1.5-3.5 parts of SBS and 0.5-1.5 parts of cross-linking agent particles; the cross-linking agent particles comprise the following components in parts by weight: 65-85 parts of liquid coumarone resin, 15-25 parts of sulfur, 5-10 parts of trichloromethane and 1-2 parts of organic tin stabilizer.

2. The SBS modified asphalt concrete according to claim 1, wherein: the preparation method of the cross-linking agent particle comprises the following steps: 1) adding ethanol with the weight of 0.6-0.8% of the total weight of the chloroform into the chloroform, and uniformly stirring to prepare a solution; 2) adding sulfur into a high-speed dispersion machine for uniform dispersion, adding the solvent in the step 1) into the high-speed dispersion machine, and dissolving the sulfur in the solvent in the high-speed rotation process; 3) then adding the liquid coumarone resin and the organic tin stabilizer into a high-speed dispersion machine, and stirring for 30mim to uniformly mix the blend; 4) and extruding, granulating and screening the blend to obtain the cross-linking agent particles.

3. The SBS modified asphalt concrete according to claim 1, wherein: the particle size of the cross-linking agent particles is 100-200 meshes.

4. The SBS modified asphalt concrete according to claim 1, wherein: the SBS modified asphalt concrete further comprises 5-10 parts of polypropylene fibers modified by chopped glass fibers.

5. The SBS modified asphalt concrete according to claim 4, wherein: the chopped glass fiber modified polypropylene fiber is subjected to spraying treatment by using an atomized accelerant before being put into a system.

6. The SBS modified asphalt concrete according to claim 5, wherein: the accelerant comprises the following components in parts by weight: 7-15 parts of zinc ethyl phenyl dithiocarbamate, 6-10 parts of zinc dibenzyl dithiocarbamate, 3-5 parts of benzoyl peroxide, 1-5 parts of ethanol and 10-30 parts of toluene.

7. The SBS modified asphalt concrete according to claim 1, wherein: the coarse and fine aggregates comprise the following components in a mass ratio of 1: (0.3-0.5): (0.4-0.8) gravel, slag and natural sand.

8. The method for preparing SBS modified asphalt concrete according to any one of claims 1 to 7, comprising the steps of:

s1, pretreatment of asphalt: preheating the asphalt, and heating the asphalt to a softening state;

s2, SBS modification: adding SBS into the asphalt treated by S1, stirring the two uniformly, and modifying the asphalt to obtain SBS modified asphalt;

s3, concrete preparation: adding coarse and fine aggregates and cross-linking agent particles into SBS modified asphalt, and stirring the mixture uniformly at the rotating speed of 40r/min to obtain the finished product.

Technical Field

The invention relates to the technical field of pavement paving materials, in particular to SBS modified asphalt concrete and a preparation method thereof.

Background

SBS is styrene-butadiene block copolymerization type thermoplastic elastomer with good processability and good fatigue resistance, and is the mainstream modification technology of asphalt pavements in China by using SBS to modify common petroleum asphalt. In the prior art, the SBS modifier, the matrix asphalt and the aggregate are directly mixed in a mixing plant to prepare the modified asphalt concrete, but the SBS modifier has high melting point and is not easy to dissolve and disperse, so the method has the defects that part of performances of the modified asphalt concrete can be reduced, and the paving effect is influenced.

In order to solve the problem, the existing SBS modified asphalt concrete is prepared by firstly carrying out high-speed shearing, ball milling and mixing on SBS and matrix asphalt to prepare SBS modified asphalt, and then mixing with aggregate to prepare the modified asphalt concrete. However, the SBS modified asphalt prepared by the method has the technical defects of easy segregation of a modifier, low thermal decomposition performance of the modifier and the like in processing and storage, and easily causes the problems of easy segregation and poor stability of SBS modified asphalt concrete. In order to solve the problem, a vulcanization crosslinking method is usually introduced into modified asphalt concrete, and the problem that a modifier in SBS modified asphalt concrete is easy to separate is solved by carrying out vulcanization crosslinking on an SBS modified asphalt system through sulfur, but the sulfur is easy to disperse unevenly and agglomerate in the SBS modified asphalt concrete system, so that the crosslinking speed of the sulfur and SBS modified asphalt is reduced, and the problem that the SBS modified asphalt concrete still has poor stability due to the general improvement effect of the method.

Disclosure of Invention

In view of the defects of the prior art, one of the purposes of the present invention is to provide an SBS modified asphalt concrete which has good stability by improving the cross-linking agent added therein.

The above object of the present invention is achieved by the following technical solutions:

the SBS modified asphalt concrete comprises the following components in parts by weight: 300-500 parts of coarse and fine aggregate, 15-30 parts of asphalt, 1.5-3.5 parts of SBS and 0.5-1.5 parts of cross linker particles; the cross-linking agent particles comprise the following components in parts by weight: 65-85 parts of liquid coumarone resin, 15-25 parts of sulfur, 5-10 parts of trichloromethane and 1-2 parts of organic tin stabilizer.

By adopting the technical scheme, the cross-linking agent is prepared into a particle form and then put into the SBS modified asphalt concrete system, because the pre-dispersion of the particles is realized in the preparation process, the dispersion uniformity of the particles is improved when the particles are dispersed in the concrete system, and the particle form is smaller than the powder form of sulfur, the agglomeration degree is smaller, and the cross-linking agent particles well improve the phenomena of uneven dispersion and agglomeration caused by directly adding sulfur into the system, so that the cross-linking speed of the cross-linking agent and SBS modified asphalt is increased, the stability effect of the cross-linking agent on the system is improved, and the stability of the SBS modified asphalt concrete is improved;

the coumarone resin has good compatibility, is used as a main material of cross-linking agent particles and added into a concrete system, not only plays a role in enhancing the strength of the system, but also has good compatibility with components such as asphalt and the like, and is favorable for further improving the uniformity of sulfur dispersed in the system and the cross-linking reaction efficiency with the asphalt in the system; the sulfur is firstly dissolved in the trichloromethane solvent and then is blended with the coumarone resin, so that the uniformity and the stability of the sulfur dispersed in the coumarone resin are improved, and the pre-dispersion effect of the sulfur is improved.

The present invention in a preferred example may be further configured to: the preparation method of the cross-linking agent particle comprises the following steps: 1) adding ethanol with the weight of 0.6-0.8% of the total weight of the chloroform into the chloroform, and uniformly stirring to prepare a solvent; 2) adding sulfur into a high-speed dispersion machine for uniform dispersion, adding the solvent in the step 1) into the high-speed dispersion machine, and dissolving the sulfur in the solvent in the high-speed rotation process; 3) then adding the liquid coumarone resin and the organic tin stabilizer into a high-speed dispersion machine, and stirring for 30mim to uniformly mix the blend; 4) and extruding, granulating and screening the blend to obtain the cross-linking agent particles.

The present invention in a preferred example may be further configured to: the particle size of the cross-linking agent particles is 100-200 meshes.

By adopting the technical scheme, the particle size of the cross-linking agent particles is not suitable to be too large, the excessive particle size can cause pores among the cross-linking agent particles, and the cross-linking agent particles are not easy to be intercalated into other components in a system and can influence the dispersion uniformity of the cross-linking agent particles; the particle diameter of the crosslinking agent particles is not necessarily too small, and although the crosslinking agent particles are pre-dispersed, the too small particle diameter may cause agglomeration, and therefore, it is necessary to control the particle diameter of the crosslinking agent particles within a suitable range.

The present invention in a preferred example may be further configured to: the SBS modified asphalt concrete further comprises 5-10 parts of polypropylene fibers modified by chopped glass fibers.

By adopting the technical scheme, the chopped glass fiber modified polypropylene fiber can partially offset the internal stress of the SBS modified asphalt concrete and inhibit the generation and development of micro cracks, and meanwhile, the addition of the chopped glass fiber modified polypropylene fiber can also improve the stress at the end of the cracks and prevent the cracks from further developing, so that the toughness of the SBS modified asphalt concrete is enhanced, and the anti-permeability and anti-cracking performance of the SBS modified asphalt concrete is improved; the support system is formed by the plurality of chopped glass fiber modified polypropylene fibers in the SBS modified asphalt concrete, so that the cohesiveness among the components of the SBS modified asphalt concrete is enhanced, the segregation of the SBS modified asphalt concrete is effectively hindered, and the stability of the SBS modified asphalt concrete is enhanced.

The present invention in a preferred example may be further configured to: the chopped glass fiber modified polypropylene fiber is subjected to spraying treatment by using an atomized accelerant before being put into a system.

By adopting the technical scheme, the accelerator is used for accelerating the crosslinking rate of the crosslinking agent particles in a concrete system, so that the segregation problem of SBS modified asphalt concrete is improved, the atomized accelerator is sprayed onto the chopped glass fiber modified polypropylene fibers, and the chopped glass fiber modified polypropylene fibers are high in dispersion degree in the system and can be inserted into coarse and fine aggregate pores, so that the surface and internal attached accelerator is more uniformly dispersed in the system, the accelerating effect of the accelerator on the crosslinking reaction speed is improved, and the stability of the concrete system structure is improved.

The present invention in a preferred example may be further configured to: the accelerant comprises the following components in parts by weight: 7-15 parts of zinc ethyl phenyl dithiocarbamate, 6-10 parts of zinc dibenzyl dithiocarbamate, 3-5 parts of benzoyl peroxide, 1-5 parts of ethanol and 10-30 parts of toluene.

By adopting the technical scheme, the zinc ethyl phenyl dithiocarbamate, the zinc dibenzyl dithiocarbamate and the benzoyl peroxide are ultra-fast accelerators, the three are selected to be used as the accelerators in the scheme, and the synergistic effect of the three is favorable for improving the accelerating effect of the crosslinking reaction rate.

The present invention in a preferred example may be further configured to: the coarse and fine aggregates comprise the following components in a mass ratio of 1: (0.3-0.5): (0.4-0.8) gravel, slag and natural sand.

By adopting the technical scheme, the gravel coarse aggregate and the slag coarse aggregate form a stable skeleton structure in the system, and then the natural sand, the SBS modified asphalt and other components are filled into the gap of the skeleton structure, so that a stable concrete structure system is formed.

The second purpose of the invention is to provide a preparation method of the SBS modified asphalt concrete.

The second aim of the invention is realized by the following technical scheme:

a preparation method of SBS modified asphalt concrete comprises the following steps:

s1, pretreatment of asphalt: preheating the asphalt, and heating the asphalt to a softening state;

s2, SBS modification: adding SBS into the asphalt treated by S1, stirring the two uniformly, and modifying the asphalt to obtain SBS modified asphalt;

s3, concrete preparation: adding coarse and fine aggregates and cross-linking agent particles into SBS modified asphalt, and stirring the mixture uniformly at the rotating speed of 40r/min to obtain the finished product.

In summary, the invention includes at least one of the following beneficial technical effects:

1. the cross-linking agent is prepared into a particle form and then put into an SBS modified asphalt concrete system, because the pre-dispersion of the particles is realized in the preparation process, the dispersion uniformity of the particles is improved when the particles are dispersed in the concrete system, and the particle form is smaller than the powder form of sulfur in the agglomeration degree, the cross-linking agent particles well improve the phenomena of uneven dispersion and agglomeration caused by directly adding the sulfur into the system, so that the cross-linking speed of the cross-linking agent and the SBS modified asphalt is improved, the stability maintaining effect of the cross-linking agent on the system is improved, and the stability of the SBS modified asphalt concrete is improved;

2. the coumarone resin has good compatibility, is used as a main material of cross-linking agent particles and added into a concrete system, not only plays a role in enhancing the strength of the system, but also has good compatibility with components such as asphalt and the like, and is favorable for further improving the uniformity of sulfur dispersed in the system and the cross-linking reaction efficiency with the asphalt in the system; the sulfur is firstly dissolved in a trichloromethane solvent and then is blended with the coumarone resin, so that the uniformity and the stability of the sulfur dispersed in the coumarone resin are improved, and the pre-dispersion effect of the sulfur is improved;

3. the chopped glass fiber modified polypropylene fiber can partially offset the internal stress of SBS modified asphalt concrete and inhibit the generation and development of micro cracks, and meanwhile, the addition of the chopped glass fiber modified polypropylene fiber can also improve the stress at the end of the cracks and prevent the cracks from further developing, so that the toughness of the SBS modified asphalt concrete is enhanced, and the anti-permeability and anti-cracking performance of the SBS modified asphalt concrete is improved; the support system is formed by the numerous chopped glass fiber modified polypropylene fibers in the SBS modified asphalt concrete, so that the cohesiveness among the components of the SBS modified asphalt concrete is enhanced, the segregation of the SBS modified asphalt concrete is effectively prevented, and the stability of the SBS modified asphalt concrete is enhanced;

4. the accelerator is used for accelerating the crosslinking rate of the crosslinking agent particles in a concrete system, so that the segregation problem of SBS modified asphalt concrete is improved, the atomized accelerator is sprayed onto the chopped glass fiber modified polypropylene fibers, and the chopped glass fiber modified polypropylene fibers are high in dispersion degree in the system and can be inserted into coarse and fine aggregate pores, so that the accelerator attached to the surface and the inside of the chopped glass fiber modified polypropylene fibers is dispersed more uniformly in the system, the accelerating effect of the accelerator on the crosslinking reaction speed is improved, and the stability of the structure of the concrete system is improved.

Detailed Description