阅读说明：本技术 一种钢渣沥青混合料及其制备方法 (Steel slag asphalt mixture and preparation method thereof ) 是由 武建民 舒志强 徐长春 李少卿 覃仲 于 2021-08-13 设计创作，主要内容包括：本发明公开了一种钢渣沥青混合料及其制备方法,该混合料包括以下重量份的组分：钢渣粗集料40-60份、石灰岩细集料20-50份、矿粉5-10份、橡胶沥青16-20份和钢渣改性剂10-20份；钢渣改性剂包括重量配比为1:1的A组分和B组分,A组分中包括质量占比为60-80％的环氧树脂和质量占比为20-40％的长链稀释剂,B组分中包括质量占比为20-35％的聚醚胺、30-40％的聚氨酯类预聚体和30-40％的改性固化剂。该钢渣沥青混合料可有效解决现有的钢渣沥青混合料存在的易开裂变形的问题。(The invention discloses a steel slag asphalt mixture and a preparation method thereof, wherein the mixture comprises the following components in parts by weight: 40-60 parts of steel slag coarse aggregate, 20-50 parts of limestone fine aggregate, 5-10 parts of mineral powder, 16-20 parts of rubber asphalt and 10-20 parts of steel slag modifier; the steel slag modifier comprises a component A and a component B in a weight ratio of 1:1, wherein the component A comprises 60-80% by mass of epoxy resin and 20-40% by mass of long-chain diluent, and the component B comprises 20-35% by mass of polyetheramine, 30-40% by mass of polyurethane prepolymer and 30-40% by mass of modified curing agent. The steel slag asphalt mixture can effectively solve the problem of easy cracking and deformation of the existing steel slag asphalt mixture.)

1. The steel slag asphalt mixture is characterized by comprising the following components in parts by weight: 40-60 parts of steel slag coarse aggregate, 20-50 parts of limestone fine aggregate, 5-10 parts of mineral powder, 16-20 parts of rubber asphalt and 10-20 parts of steel slag modifier;

the steel slag modifier comprises a component A and a component B in a weight ratio of 1:1, wherein the component A comprises 60-80% by mass of epoxy resin and 20-40% by mass of long-chain diluent, and the component B comprises 20-35% by mass of polyether amine, 30-40% by mass of polyurethane prepolymer and 30-40% by mass of modified curing agent.

2. The steel slag asphalt mixture according to claim 1, which comprises the following components in parts by weight: 50 parts of steel slag coarse aggregate, 30 parts of limestone fine aggregate, 8 parts of mineral powder, 20 parts of rubber asphalt and 15 parts of steel slag modifier;

the steel slag modifier comprises a component A and a component B in a weight ratio of 1:1, wherein the component A comprises 70% by mass of epoxy resin and 30% by mass of long-chain diluent, and the component B comprises 25% by mass of polyetheramine, 35% by mass of polyurethane prepolymer and 40% by mass of a modifying and curing agent.

3. The steel slag bituminous mixture of claim 1 or 2, wherein in said steel slag coarse aggregate, steel slag of 4.7-9.5mm accounts for 25-40%, steel slag of 9.5-13mm accounts for 25-40%, and steel slag of 13-16mm accounts for 25-40%.

4. The steel slag bituminous mixture of claim 3, wherein said limestone fine aggregates have a size of 0-4.75 mm.

5. The steel slag bituminous mixture of claim 4, wherein said long chain reactive diluent contains epoxy groups at both ends.

6. The steel slag asphalt mixture as claimed in claim 5, wherein the polyurethane prepolymer is a soybean oil-based polyurethane prepolymer.

7. The method for preparing a steel slag asphalt mixture according to claim 6, comprising the steps of:

(1) uniformly mixing the epoxy resin in the component A with the long-chain diluent, then adding the steel slag into the mixture, and stirring the mixture until the mixture is uniformly mixed to obtain a steel slag mixture;

(2) heating the polyether amine in the component B to 70-75 ℃, adding a modified curing agent and a polyurethane prepolymer under the stirring condition, and uniformly mixing to obtain a cured mixture;

(3) under the stirring condition, slowly adding the solidified mixture and the mineral powder in the step (2) into the steel slag mixture in the step (1) in sequence, and uniformly mixing to obtain a modified steel slag mixture;

(4) respectively heating the modified steel slag mixture, the rubber asphalt and the limestone fine aggregate, then adding the rubber asphalt into the modified steel slag mixture while stirring, then adding the limestone fine aggregate, and uniformly mixing to obtain the modified steel slag mixture.

8. The steel slag bituminous mixture of claim 7, wherein the stirring speed in step (1) is 700-900 r/min.

9. The steel slag bituminous mixture according to claim 7, characterized in that the mineral powder is added after the solidified mixture is added for 3-6min in step (3).

10. The steel slag bituminous mixture according to claim 7, wherein the heating temperature in step (4) is 170-190 ℃.

Technical Field

The invention relates to the technical field of asphalt roads, in particular to a steel slag asphalt mixture and a preparation method thereof.

Background

The rapid development of the traffic industry in China stimulates the increase of the raw material demand, and stone as an important component in buildings and infrastructure structures accounts for more than 90% of the mass composition of road structures. The excessive exploitation of natural stones causes the condition of building material shortage in half of domestic areas, and the exploitation of stones has adverse effect on the river ecological environment. Therefore, it is urgent to find a renewable material which is abundant and meets the road construction standards.

The yield of the steel slag in the crude steel refining process is about 12 to 20 percent. The steel slag can replace limestone to be recycled in the steel-making process, and the steel slag after being treated can also play a role in waste heat in the fields of buildings and agriculture; although a great deal of research on application of steel slag and rubber powder to road engineering at home and abroad is carried out, the steel slag material serving as a by-product in the steel making process is different from the thermal properties of common road materials such as limestone and basalt, when the thermal properties of the materials at all positions of the road surface are greatly different, the temperature distribution inside the layered road surface is changed, so that the high-temperature deformation resistance and the low-temperature crack resistance of a mixture made of the steel slag are deteriorated, and the steel slag contains a large amount of free calcium oxide and magnesium oxide, and the volume of the steel slag expands after meeting water, so that the problems of cracking, deformation and the like of the road surface are easily caused by the reasons.

Disclosure of Invention

Aiming at the defects in the prior art, the invention provides the steel slag asphalt mixture and the preparation method thereof, and the steel slag asphalt mixture can effectively solve the problem of easy cracking and deformation of the existing steel slag asphalt mixture.

In order to achieve the purpose, the technical scheme adopted by the invention for solving the technical problems is as follows:

the steel slag asphalt mixture comprises the following components in parts by weight: 40-60 parts of steel slag coarse aggregate, 20-50 parts of limestone fine aggregate, 5-10 parts of mineral powder, 16-20 parts of rubber asphalt and 10-20 parts of steel slag modifier;

the steel slag modifier comprises a component A and a component B in a weight ratio of 1:1, wherein the component A comprises 60-80% by mass of epoxy resin and 20-40% by mass of long-chain diluent, and the component B comprises 20-35% by mass of polyetheramine, 30-40% by mass of polyurethane prepolymer and 30-40% by mass of modified curing agent.

Further, the paint comprises the following components in parts by weight: 50 parts of steel slag coarse aggregate, 30 parts of limestone fine aggregate, 8 parts of mineral powder, 20 parts of rubber asphalt and 15 parts of steel slag modifier;

the steel slag modifier comprises a component A and a component B in a weight ratio of 1:1, wherein the component A comprises 70% by mass of epoxy resin and 30% by mass of long-chain diluent, and the component B comprises 25% by mass of polyether amine, 35% by mass of polyurethane prepolymer and 40% by mass of modified curing agent.

Furthermore, in the steel slag coarse aggregate, the steel slag with the thickness of 4.7-9.5mm accounts for 25-40%, the steel slag with the thickness of 9.5-13mm accounts for 25-40%, and the steel slag with the thickness of 13-16mm accounts for 25-40%.

In the scheme, after the component A and the component B in the steel slag modifier are mixed, a hydrophobic film formed by crosslinking is wrapped outside the steel slag, so that the condition that the pavement is broken due to absorption and expansion of the steel slag in the subsequent use process is avoided, and the water stability of the pavement is improved; and the formed hydrophobic film has certain elasticity and toughness, so that the rigidity of the road surface can be reduced, and the comfort and the wear resistance of the vehicle when the vehicle runs on the road surface are improved.

Further, the size of the limestone fine aggregate is 0-4.75 mm.

Furthermore, the long-chain reactive diluent contains epoxy groups at two ends.

Further, the polyurethane prepolymer is a soybean oil-based polyurethane prepolymer.

The preparation method of the steel slag asphalt mixture comprises the following steps:

(1) uniformly mixing the epoxy resin in the component A with the long-chain diluent, then adding the steel slag into the mixture, and stirring the mixture until the mixture is uniformly mixed to obtain a steel slag mixture;

(2) heating the polyether amine in the component B to 70-75 ℃, adding a modified curing agent and a polyurethane prepolymer under the stirring condition, and uniformly mixing to obtain a cured mixture;

(3) under the stirring condition, slowly adding the solidified mixture and the mineral powder in the step (2) into the steel slag mixture in the step (1) in sequence, and uniformly mixing to obtain a modified steel slag mixture;

(4) respectively heating the modified steel slag mixture, the rubber asphalt and the limestone fine aggregate, then adding the rubber asphalt into the modified steel slag mixture while stirring, then adding the limestone fine aggregate, and uniformly mixing to obtain the modified steel slag mixture.

Further, the stirring speed in the step (1) is 700-.

Further, adding the solidified mixture in the step (3) for 3-6min, and then adding the mineral powder.

Further, the heating temperature in the step (4) is 170-.

According to the scheme, after the epoxy resin and the long-chain diluent of the component A are mixed, a liquid material formed by mixing the epoxy resin and the long-chain diluent of the component A is mixed with the steel slag, the mixture in the component B is uniformly distributed on the surface of the steel slag, then the mixture in the component B is heated and added into the steel slag, and the polyether amine and the modified curing agent in the component B can be subjected to curing reaction with the epoxy resin to form a hydrophobic cross-linked structure to be adhered to the surface of the steel slag, so that the steel slag is prevented from directly contacting with water, and the subsequent volume expansion is avoided to cause pavement fracture; the cross-linked structure is also used as a binder to bind the steel slag with limestone aggregates and other raw materials, so that the strength of the formed steel slag concrete is improved, the pavement cracking condition is reduced, and the service life of the pavement is prolonged;

the modified curing agent is prepared by performing Mannich modification on an aliphatic amine curing agent, nonyl phenol, formaldehyde and the like, the number of carbon atoms in a molecular chain of the long-chain reactive diluent is more than 10, and the modified curing agent can react with an epoxy group in the long-chain reactive diluent, so that a reactant has certain elasticity, the hardness of the steel slag concrete pavement is reduced, and the driving comfort is improved;

the polyurethane prepolymer contains an amino structure, can also perform a crosslinking reaction with epoxy resin to promote the curing of the epoxy resin, and also contains a large number of ether bonds, so that the toughness of the crosslinking structure is improved by utilizing the free rotation characteristic of the ether bonds, the hardness of the steel slag concrete pavement is further reduced, and the driving comfort is improved.

After a certain amount of the component B is added, mineral powder is added into the steel slag at the same time, and the mineral powder is utilized to disperse the cross-linked and solidified colloid on the surface of the steel slag, so that a film-shaped structure with uniform thickness is formed on the surface of the steel slag, the hydrophobicity of the steel slag and the uniformity of the mixed material are improved, and all raw materials in the paved road surface are uniformly distributed.

The beneficial effects produced by the invention are as follows:

1. after the steel slag is modified by using the steel slag modifier, a hydrophobic film structure with uniform thickness can be formed on the surface of the steel slag, and the film can be used for preventing water, so that rainwater and the like are prevented from permeating into the steel slag to cause the volume expansion of the steel slag, and the pavement is cracked; the steel slag can be used as a binder, and the steel slag and other raw materials are bound together with asphalt, so that the stability of the pavement is improved, and the strength of the pavement after pavement is improved; the film has certain elasticity and toughness, and can reduce the hardness of a road surface after being used and improve the travelling comfort.

2. The preparation process of the steel slag asphalt mixture is set according to the characteristics of each raw material, the mixture formed by the component B of the steel slag modifier and mineral powder are sequentially added into modified steel slag, the component A and the component B are added into mineral powder for stirring after being contacted and crosslinked on the surface of the steel slag, and the steel slag can be separated by utilizing the mineral powder, so that the condition that the whole solidification is formed between the steel slag and the laying effect is influenced is avoided.

Detailed Description

Example 1

The steel slag asphalt mixture comprises the following components in parts by weight: 40 parts of steel slag coarse aggregate, 20 parts of limestone fine aggregate, 5 parts of mineral powder, 16 parts of rubber asphalt and 10 parts of steel slag modifier; wherein, in the steel slag coarse aggregate, 4.7-9.5mm of steel slag accounts for 25 percent, 9.5-13mm of steel slag accounts for 35 percent, and 13-16mm of steel slag accounts for 40 percent; the size of the limestone fine aggregate is 0-4.75 mm;

the steel slag modifier comprises a component A and a component B in a weight ratio of 1:1, wherein the component A comprises 60% by mass of epoxy resin and 40% by mass of long-chain diluent, and the component B comprises 20% by mass of polyetheramine, 40% by mass of polyurethane prepolymer and 40% by mass of modified curing agent; wherein, both ends of the long-chain reactive diluent contain epoxy groups, and the polyurethane prepolymer is soybean oil-based polyurethane prepolymer.

The preparation method of the steel slag asphalt mixture comprises the following steps:

(1) uniformly mixing the epoxy resin in the component A with the long-chain diluent, then adding the steel slag into the mixture, and stirring the mixture at the speed of 700r/min until the mixture is uniformly mixed to obtain a steel slag mixture;

(2) heating the polyether amine in the component B to 70 ℃, adding a modified curing agent and a polyurethane prepolymer into the mixture under the stirring condition, and uniformly mixing to obtain a cured mixture;

(3) under the condition of stirring at the speed of 700r/min, slowly adding the solidified mixture and the mineral powder in the step (2) into the steel slag mixture in the step (1) in sequence, and uniformly mixing to obtain a modified steel slag mixture, wherein the mineral powder is added after the solidified mixture is added for 3 min;

(4) respectively heating the modified steel slag mixture, the rubber asphalt and the limestone fine aggregate to 170 ℃, then adding the rubber asphalt into the modified steel slag mixture while stirring, then adding the limestone fine aggregate, and uniformly mixing to obtain the modified steel slag mixture.

Example 2

The steel slag asphalt mixture comprises the following components in parts by weight: 60 parts of steel slag coarse aggregate, 50 parts of limestone fine aggregate, 10 parts of mineral powder, 20 parts of rubber asphalt and 15 parts of steel slag modifier; wherein, in the steel slag coarse aggregate, 4.7-9.5mm of steel slag accounts for 40 percent, 9.5-13mm of steel slag accounts for 35 percent, and 13-16mm of steel slag accounts for 25 percent; the size of the limestone fine aggregate is 0-4.75 mm;

the steel slag modifier comprises a component A and a component B in a weight ratio of 1:1, wherein the component A comprises 80% by mass of epoxy resin and 20% by mass of long-chain diluent, and the component B comprises 35% by mass of polyetheramine, 40% by mass of polyurethane prepolymer and 25% by mass of modified curing agent; wherein, both ends of the long-chain reactive diluent contain epoxy groups, and the polyurethane prepolymer is soybean oil-based polyurethane prepolymer.

The preparation method of the steel slag asphalt mixture comprises the following steps:

(1) uniformly mixing the epoxy resin in the component A with the long-chain diluent, then adding the steel slag into the mixture, and stirring the mixture at the speed of 900r/min until the mixture is uniformly mixed to obtain a steel slag mixture;

(2) heating the polyether amine in the component B to 75 ℃, adding a modified curing agent and a polyurethane prepolymer into the mixture under the stirring condition, and uniformly mixing to obtain a cured mixture;

(3) under the condition of stirring at the speed of 900r/min, slowly adding the solidified mixture and the mineral powder in the step (2) into the steel slag mixture in the step (1) in sequence, and uniformly mixing to obtain a modified steel slag mixture, wherein the mineral powder is added after the solidified mixture is added for 6 min;

(4) respectively heating the modified steel slag mixture, the rubber asphalt and the limestone fine aggregate to 190 ℃, then adding the rubber asphalt into the modified steel slag mixture while stirring, then adding the limestone fine aggregate, and uniformly mixing to obtain the modified steel slag mixture.

Example 3

The steel slag asphalt mixture comprises the following components in parts by weight: 50 parts of steel slag coarse aggregate, 30 parts of limestone fine aggregate, 8 parts of mineral powder, 20 parts of rubber asphalt and 15 parts of steel slag modifier; wherein, in the steel slag coarse aggregate, 4.7-9.5mm of steel slag accounts for 30 percent, 9.5-13mm of steel slag accounts for 30 percent, and 13-16mm of steel slag accounts for 40 percent; the size of the limestone fine aggregate is 0-4.75 mm;

the steel slag modifier comprises a component A and a component B in a weight ratio of 1:1, wherein the component A comprises 70% by mass of epoxy resin and 30% by mass of long-chain diluent, and the component B comprises 25% by mass of polyetheramine, 35% by mass of polyurethane prepolymer and 40% by mass of modified curing agent; wherein, both ends of the long-chain reactive diluent contain epoxy groups, and the polyurethane prepolymer is soybean oil-based polyurethane prepolymer.

The preparation method of the steel slag asphalt mixture comprises the following steps:

(1) uniformly mixing the epoxy resin in the component A with the long-chain diluent, then adding the steel slag into the mixture, and stirring the mixture at the speed of 900r/min until the mixture is uniformly mixed to obtain a steel slag mixture;

(2) heating the polyether amine in the component B to 72 ℃, adding a modified curing agent and a polyurethane prepolymer into the mixture under the stirring condition, and uniformly mixing to obtain a cured mixture;

(3) under the condition of stirring at the speed of 900r/min, slowly adding the solidified mixture and the mineral powder in the step (2) into the steel slag mixture in the step (1) in sequence, and uniformly mixing to obtain a modified steel slag mixture, wherein the mineral powder is added after the solidified mixture is added for 4 min;

(4) respectively heating the modified steel slag mixture, the rubber asphalt and the limestone fine aggregate to 180 ℃, then adding the rubber asphalt into the modified steel slag mixture while stirring, then adding the limestone fine aggregate, and uniformly mixing to obtain the modified steel slag mixture.

Comparative example 1

The steel slag asphalt mixture comprises the following components in parts by weight: 50 parts of steel slag coarse aggregate, 30 parts of limestone fine aggregate, 8 parts of mineral powder and 20 parts of rubber asphalt; wherein, in the steel slag coarse aggregate, 4.7-9.5mm of steel slag accounts for 30 percent, 9.5-13mm of steel slag accounts for 30 percent, and 13-16mm of steel slag accounts for 40 percent; the size of the limestone fine aggregate is 0-4.75 mm.

The preparation method of the steel slag asphalt mixture comprises the following steps:

respectively heating the steel slag coarse aggregate, the rubber asphalt, the mineral powder and the limestone fine aggregate to 180 ℃, then adding the rubber asphalt into the steel slag mixture while stirring, then adding the mineral powder and the limestone fine aggregate, and uniformly mixing to obtain the steel slag-reinforced concrete.

Comparative example 2

The steel slag asphalt mixture comprises the following components in parts by weight: 50 parts of steel slag coarse aggregate, 30 parts of limestone fine aggregate, 8 parts of mineral powder, 20 parts of rubber asphalt and 15 parts of steel slag modifier; wherein, in the steel slag coarse aggregate, 4.7-9.5mm of steel slag accounts for 30 percent, 9.5-13mm of steel slag accounts for 30 percent, and 13-16mm of steel slag accounts for 40 percent; the size of the limestone fine aggregate is 0-4.75 mm;

the steel slag modifier comprises a component A and a component B in a weight ratio of 1:1, wherein the component A is epoxy resin, and the component B is polyether amine; wherein, both ends of the long-chain reactive diluent contain epoxy groups.

The preparation method of the steel slag asphalt mixture comprises the following steps:

(1) adding the epoxy resin in the component A into the steel slag, and stirring at the speed of 900r/min until the epoxy resin and the steel slag are uniformly mixed to obtain a steel slag mixture;

(2) heating the polyetheramine in the component B to 72 ℃, slowly adding the polyetheramine and the mineral powder into the steel slag mixture in the step (1) successively under the stirring condition of 900r/min, and uniformly mixing to obtain a modified steel slag mixture, wherein the mineral powder is added after the polyetheramine is added for 4 min;

(3) respectively heating the modified steel slag mixture, the rubber asphalt and the limestone fine aggregate to 180 ℃, then adding the rubber asphalt into the modified steel slag mixture while stirring, then adding the limestone fine aggregate, and uniformly mixing to obtain the modified steel slag mixture.

Test examples

1. High temperature stability test

According to road engineering asphalt and asphalt mixture experimental procedures (JTG E20-2011), a rutting test is adopted to evaluate the high-temperature stability. In the rutting test, an asphalt concrete plate type test piece is formed by using a standard wheel rolling method, the contact wheel pressure is 0.7MPa at 60 ℃, a rolling wheel rolls and rolls along the same track of the surface of the test piece in a reciprocating manner, the rutting depth formed on the surface of the test piece under the repeated action of the test wheel is measured, and the specific result is shown in table 1.

Table 1: rut test results

As can be seen from the data in the table, the test results in examples 1-3 are all better than those in comparative examples 1-2, which proves that the steel slag asphalt mixture prepared by the method in the application has better performance.

2. Low temperature crack resistance test

And (3) applying a concentrated load to the span of the asphalt mixture trabecula test piece at the temperature of minus 10 ℃ at the speed of 5mm/min until the fracture is destroyed, and calculating the destructive bending tensile stress strain of the asphalt mixture.

Table 2: results of crack resistance test

	Maximum load (N)	Flexural tensile Strength (MPa)	Maximum bending strain (mu epsilon)
				Example 1	1259.5	9.11	2745
Example 2	1247.6	9.08	2731
				Example 3	1261.3	9.15	2758
Comparative example 1	1142.3	8.81	2670
				Comparative example 2	1145.3	8.79	2684

As can be seen from the data in the above table, the crack resistance of the steel slag asphalt mixture of examples 1-3 is due to the crack resistance of comparative examples 1-2.

3. Expansion test

The steel slag expansibility test was performed according to road engineering aggregate test procedure (JTG E42-2005). Firstly, 3 standard Marshall test pieces are manufactured, the diameter and the height of the test piece before soaking are tested by a vernier caliper, the initial volume is obtained by calculation, then the test piece is soaked in a constant temperature water tank with the temperature of 60 +/-1 ℃ for 72 hours, then the diameter and the height are taken out to be measured, the volume after soaking is obtained, and finally the expansion rate of the steel slag asphalt concrete is calculated.

Table 3: expansion rate results

	Swelling rate in water%
		Example 1	0.79
Example 2	0.81
		Example 3	0.77
Comparative example 1	0.85
		Comparative example 2	0.89

From the expansion ratio results, it is understood that the expansion ratios of the test pieces in examples 1 to 3 are lower than those in comparative examples 1 to 2.