CN115433468A

CN115433468A - High-viscosity emulsified asphalt cold-laid overlay material and preparation method thereof

Info

Publication number: CN115433468A
Application number: CN202211199985.6A
Authority: CN
Inventors: 李小伟; 苏利民; 鲁美
Original assignee: Shanghai Longfu Road Maintenance Engineering Co ltd
Current assignee: Shanghai Longfu Road Maintenance Engineering Co ltd
Priority date: 2022-09-29
Filing date: 2022-09-29
Publication date: 2022-12-06
Anticipated expiration: 2042-09-29
Also published as: CN115433468B

Abstract

The invention discloses the technical field of paving, and particularly relates to a high-viscosity emulsified asphalt cold-paving overlay material and a preparation method thereof. The invention relates to a high-viscosity emulsified asphalt cold-laid overlay material which comprises the following raw materials in parts by weight: 55-65 parts of matrix asphalt, 3-5 parts of hydrophilic silicon dioxide, 5-8 parts of emulsifier, 2-4 parts of SBR latex, 2-4 parts of high chlorinated polyethylene, 1-2 parts of phthalimide and 20-25 parts of water. The obtained cover material has excellent performance, and can well solve the problems of low strength, easy peeling and loosening of the prior cold-laid cover asphalt surface.

Description

High-viscosity emulsified asphalt cold-laid overlay material and preparation method thereof

Technical Field

The invention belongs to the technical field of paving, and particularly relates to a high-viscosity emulsified asphalt cold-paving overlay material and a preparation method thereof.

Background

The cold-laid overlay is made up by mixing modified emulsified asphalt with aggregate according to a certain gradation, and the general method is to use slurry seal process or micro-surfacing process to make the overlay, and its performance depends on the self-adhesive strength of the binder. The application of the ultrathin asphalt overlay in maintenance engineering of various grades of highway pavements is quite extensive, but the development of the more environment-friendly and more convenient cold-laid asphalt overlay technology is always slow, the cold-laid asphalt overlay has the characteristics of convenience and economy, and the key for hindering the popularization of the ultrathin asphalt overlay is low strength, easy peeling and loosening, which is always the key point of more question and concern of engineering personnel.

Disclosure of Invention

In order to solve the above problems, the inventors found in long-term practice and research that better adhesive properties can be obtained by adjusting the formula of the modifier in the binder and adjusting the corresponding gradation.

The formula of the high-viscosity emulsified asphalt cold-laid cover material comprises base asphalt, hydrophilic silica, an emulsifier, SBR latex, high chlorinated polyethylene, phthalimide and water, wherein the weight parts of the raw materials are as follows:

the hydrophilic silica is used for improving the viscosity of liquid and is mainly used for suspending the high chlorinated polyethylene particles. The invention requires that the particle size of the hydrophilic silicon dioxide is as follows: 7-20nm, specific surface area: 90-400 square meters per gram.

Wherein, the emulsifier is water which is a cation emulsifier for common emulsified asphalt and has no other special requirements.

Wherein, the SBR latex is the SBR styrene-butadiene rubber latex for common emulsified asphalt and has no other special requirements.

Wherein, the high chlorinated polyethylene is used for enhancing the bonding strength of the emulsified asphalt, and the specific requirements are shown in the table 1:

TABLE 1 index of the requirements of the highly chlorinated polyethylene

Chlorine content (%)	64-68
		Viscosity (mPa.s) dichloroethane 10% by weight of 25%	360-540
The thermal decomposition temperature (DEG C) is not less than	100
		Drying weight loss ((%) is less than or equal to	0.4

Wherein, the phthalimide is used for enhancing the high-efficiency ion exchange effect between the high-chlorinated polyethylene and the asphalt after the high-chlorinated polyethylene is subjected to alkylation, namely the high-chlorinated polyethylene and the asphalt molecules are better combined, the proportion of the phthalimide to the high-chlorinated polyethylene is 1.5-2.5, and the phthalimide has the following structural formula:

wherein, the water is used for common emulsified asphalt and has no other special requirements.

Wherein, the matrix asphalt needs to be modified by high chlorinated polyethylene and phthalimide at a certain temperature, generally 140-160 ℃, and then the SBR latex and the emulsifier need to be dispersed in water through a colloid mill to obtain the binder of the material of the invention. The binder can be filled at normal temperature for long-term storage, and when the binder is to be used, the prepared binder is mixed with aggregate and mineral powder, and the final asphalt mixture for cold-paving overlay is carried out, namely the high-viscosity emulsified asphalt cold-paving overlay material. The grading is shown in Table 3, the passing rate is controlled between the upper limit and the lower limit, and the mass ratio of the ore powder is below the sieve hole of 0.075 mm.

Detailed Description

Examples 1-4 binder preparations were made according to the formulation of table 2:

TABLE 2 examples 1-4 ratios

After the binder is prepared, the cold-laid overlay mixture is prepared by blending according to the median grade in table 3:

TABLE 3 passage statistics

Comparative example: the SBS modified emulsified asphalt which is a common asphalt binder used for cold-mix cold-spread asphalt thin-layer overlay is selected, and the preparation process of the mixture is the same as that of the embodiment. Preparing a cold-laid overlay mixture by mixing according to the following grades:

the examples and comparative examples were prepared into marshall test pieces according to the standard procedures of the test procedures for road asphalt and asphalt mixtures, and the following tests were carried out, with the results shown in table 4.

TABLE 4 Performance

From the test results, it can be seen that the data closely related to the adhesive property show that the examples greatly exceed the comparative examples, and the obtained cover material has excellent performance, and can well solve the problems of low strength, easy peeling and loosening of the asphalt surface layer of the current cold-paved cover.

The foregoing is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, various modifications and amendments can be made without departing from the principle of the present invention, and these modifications and amendments should also be considered as the protection scope of the present invention.

Claims

1. The high-viscosity emulsified asphalt cold-laid overlay material is characterized by comprising the following raw materials in parts by weight: 55-65 parts of matrix asphalt, 3-5 parts of hydrophilic silicon dioxide, 5-8 parts of emulsifier, 2-4 parts of SBR latex, 2-4 parts of high chlorinated polyethylene, 1-2 parts of phthalimide and 20-25 parts of water.

2. The high viscosity emulsified asphalt cold-laid overlay material according to claim 1, wherein the particle size of the hydrophilic silica is 7-20nm, and the specific surface area is 90-400 square meters per gram.

3. The high viscosity emulsified asphalt cold-laid finishing material as claimed in claim 1, wherein the emulsifier comprises a cationic emulsifier.

4. The high viscosity emulsified asphalt cold-laid finishing material as claimed in claim 1, wherein the SBR latex comprises SBR styrene-butadiene rubber latex for emulsified asphalt.

5. The high-viscosity emulsified asphalt cold-paving finishing material as claimed in claim 1, wherein the weight ratio of the phthalimide to the high chlorinated polyethylene is 1.5-2.5.

6. The method for preparing the high-viscosity emulsified asphalt cold-laid overlay material according to any one of claims 1 to 5, which is characterized by comprising the following steps: mixing the substrate asphalt with high chlorinated polyethylene and phthalimide for modification;

mixing SBR latex and an emulsifier, and dispersing the mixture in water to obtain a binder;

and mixing and stirring the modified asphalt, the binder and the hydrophilic silicon dioxide to obtain the high-viscosity emulsified asphalt cold-laid overlay material.

7. The method according to claim 6, wherein the temperature of the modification is 140 to 160 ℃.