Polyester fiber coal gangue powder modified rubber asphalt mortar and preparation method thereof

Abstract

The invention discloses polyester fiber coal gangue powder modified rubber asphalt mortar and a preparation method thereof, the rubber asphalt mortar comprises rubber asphalt, coal gangue powder and polyester fibers, and the mass ratio of the rubber asphalt to the coal gangue powder to the polyester fibers is 1: (0.5-0.8): (0.003-0.005). According to the polyester fiber coal gangue powder modified rubber asphalt mortar adopting the structure and the preparation method thereof, the added polyester fibers have the advantages of soft texture, high monofilament tensile strength and the like, and the high-temperature performance of the rubber asphalt mortar is greatly improved due to the addition of the polyester fibers.

Description

Technical Field

[0001] The invention relates to the technical field of rubber asphalt materials, in particular to a polyester fiber and coal gangue powder modified rubber asphalt mortar and a preparation method thereof. Background Art

[0002] Rubber asphalt pavement is a high-grade pavement used in my country's road types and is applied to urban roads and highway trunk lines. Rubber asphalt mixture is made by mixing rubber asphalt, filler and coarse and fine aggregates. The amount of rubber asphalt content is closely related to the various performance indicators of rubber asphalt mixture. Too much rubber asphalt content will cause the road surface to become oily and softened, while too little rubber asphalt content will cause looseness and pockmarks. Rubber asphalt mortar is made by mixing filler-absorbed rubber asphalt. The types and properties of rubber asphalt and filler will affect the performance of rubber asphalt mortar, so it is very important to make the performance of rubber asphalt mortar reach the best state.

[0003] Traditional rubber asphalt mortar generally has good adhesion, flexibility, weather resistance, wear resistance and water resistance, among which good adhesion performance ensures that the rubber asphalt mortar can firmly adhere to the surface of the substrate; flexibility gives it a higher elastic modulus, which can absorb stress to a certain extent without cracking; weather resistance enables it to maintain its physical and chemical properties under different climatic conditions and is not easy to age and deteriorate; wear resistance enables it to resist wear and maintain surface smoothness and friction; water resistance enables it to form an effective waterproof barrier to prevent moisture from penetrating into the roadbed and protect the road structure.

[0004] Although rubber asphalt mortar has the above advantages, it also has some disadvantages. For example, although rubber modified asphalt has a higher softening point than ordinary asphalt, under extremely high temperature conditions, rubber asphalt mortar may still become too soft, resulting in flow deformation and affecting the smoothness of the road surface. In high temperature environments, especially under heavy traffic conditions, rubber asphalt mortar may form rutting, i.e. depressions in the road surface, because it cannot effectively disperse vehicle loads. Summary of the invention

[0005] The purpose of the present invention is to provide a polyester fiber gangue powder modified rubber asphalt mortar and a preparation method thereof, so as to solve the problem that the above-mentioned rubber asphalt mortar has poor high temperature resistance and forms rutting under heavy load traffic conditions.

[0006] To achieve the above-mentioned purpose, the first aspect of the present invention provides a polyester fiber and coal gangue powder modified rubber asphalt mortar, characterized in that the rubber asphalt mortar comprises rubber asphalt, coal gangue powder and polyester fiber, and the mass ratio of rubber asphalt, coal gangue powder and polyester fiber is 1:0.5~0.8:0.003~0.005.

[0007] Preferably, the rubber powder content of the rubber asphalt is 20%, the softening point is 65°C to 70°C, the needle penetration at 25°C is 40mm to 45mm, and the elongation at 5°C is 6.5mm to 7.0mm.

[0008] Preferably, the specific surface area of ​​the coal gangue powder is not less than 8.53m 2 / g.

[0009] Preferably, the polyester fiber has a length of 6 mm and a diameter of 10 to 25 μm.

[0010] Preferably, the density of the polyester fiber is 1.37 g / cm 3 , tensile elastic modulus>7000MPa, tensile strength>680MPa, melting point is 260℃.

[0011] The second aspect of the present invention provides a method for preparing polyester fiber gangue powder modified rubber asphalt mortar, comprising the following steps:

[0012] (1) Screening the gangue powder to remove large particles and debris, and melting the rubber asphalt in an oven;

[0013] (2) adding the screened coal gangue powder into the melted rubber asphalt in proportion and mixing them to obtain modified rubber asphalt;

[0014] (3) Add polyester fiber to modified rubber asphalt in proportion and mix evenly to obtain rubber asphalt mortar.

[0015] Preferably, in step (1), the gangue powder is sieved through a 0.075 mm sieve.

[0016] Preferably, the gangue powder in step (1) is sieved and then dried at 55-65° C. for 0.5-2 h to remove excess moisture; and the polyester fiber in step (3) is dried at 55-65° C. for 0.5-2 h to remove excess moisture.

[0017] Preferably, the melting temperature of the rubber asphalt in step (1) is 180-190°C.

[0018] Preferably, the mixing temperature in step (2) and step (3) is 175-185° C., the mixing stirring rate is 800-1200 r / min, and the mixing time is 0.5-3 h to eliminate internal bubbles in the mortar.

[0019] Therefore, the present invention adopts a polyester fiber gangue powder modified rubber asphalt mortar and a preparation method thereof, which has the following beneficial effects:

[0020] (1) In the present invention, waste coal gangue powder and rubber asphalt are used to prepare mortar. Since the rubber asphalt contains rubber powder, the rubber powder adsorbs free asphalt to reduce the fluidity of the asphalt mortar system, thereby greatly improving the high temperature resistance of the mortar.

[0021] (2) The rubber particles in the present invention can also play a reinforcing role in asphalt, thereby improving the elasticity and low-temperature crack resistance of asphalt to a certain extent.

[0022] (3) The coal gangue powder used in the present invention has a rough surface structure and contains active mineral components such as silicon dioxide and aluminum oxide, which further enhances the modification effect.

[0023] (4) The present invention also adds polyester fibers, which are dispersed inside the mortar to form a three-dimensional spatial structure, thereby increasing the shear force of the mortar, increasing the viscosity, and improving the high temperature resistance of the mortar.

[0024] (5) The coal gangue powder and rubber asphalt used in the present invention are both waste resources. On the one hand, they improve the performance of the mortar, and on the other hand, they realize the utilization of waste, which has practical significance for sustainable development and also has certain economic benefits.

[0025] The technical solution of the present invention is further described in detail below through the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 The figure is the preparation process of the glue;

[0027] Figure 2 Schematic diagram of the dynamic rheological test results of the slurries prepared in the examples and comparative examples. DETAILED DESCRIPTION

[0028] The present invention will be further described below. It should be noted that this embodiment is based on the technical solution and provides a detailed implementation method and a specific operation process, but the present invention is not limited to this embodiment.

[0029] Example 1

[0030] A method for preparing polyester fiber gangue powder modified rubber asphalt mortar specifically comprises the following steps:

[0031] 1) The gangue powder was sieved through a 0.075 mm sieve to remove large particles and other debris. The sieved gangue powder and polyester fiber were dried in an oven at 60°C for 0.5 h to remove surface moisture, and the rubber asphalt was placed in an oven at 185°C to completely melt.

[0032] The rubber powder content of rubber asphalt is 20%, the softening point is 65℃~70℃, the needle penetration at 25℃ is 40mm~45mm, and the elongation at 5℃ is 6.5mm~7.0mm.

[0033] The specific surface area of ​​coal gangue powder is not less than 8.53m 2 / g. Coal gangue powder was purchased from Taizhen Mineral Products Processing Plant in Lingshou County.

[0034] The length of the polyester fiber is 6 mm and the diameter is 10-25 μm. The polyester fiber was purchased from Shandong Anhe New Materials Co., Ltd.

[0035] The density of polyester fiber is 1.37g / cm 3 , tensile elastic modulus>7000MPa, tensile strength>680MPa, melting point is 260℃.

[0036] 2) The rubber asphalt is mixed with coal gangue powder in a mass ratio of 1:0.6 to obtain modified rubber asphalt.

[0037] 3) The polyester fiber and the modified rubber asphalt are then mixed, and the mass ratio of the polyester fiber to the rubber asphalt is 0.003:1.

[0038] 4) The mixing temperature of the mortar is controlled at 180°C, the stirring rate is controlled at 1000 rpm, and the mixing time is 0.5h to eliminate internal bubbles in the mortar and obtain a uniform polyester fiber coal gangue powder modified rubber asphalt mortar.

[0039] Example 2

[0040] The difference between this embodiment and embodiment 1 is that the amount of polyester fiber added is different.

[0041] A method for preparing polyester fiber gangue powder modified rubber asphalt mortar specifically comprises the following steps:

[0042] 1) The gangue powder was sieved through a 0.075 mm sieve to remove large particles and other debris. The sieved gangue powder and polyester fiber were dried in an oven at 60°C for 0.5 h to remove surface moisture, and the rubber asphalt was placed in an oven at 185°C to completely melt.

[0043] 2) The rubber asphalt is mixed with coal gangue powder in a mass ratio of 1:0.6 to obtain modified rubber asphalt.

[0044] 3) The polyester fiber is then mixed with the modified rubber asphalt, and the mass ratio of the polyester fiber to the rubber asphalt is 0.004:1.

[0045] 4) The mixing temperature of the mortar is controlled at 180°C, the stirring rate is controlled at 1000 rpm, and the mixing time is 0.5h to eliminate internal bubbles in the mortar and obtain a uniform polyester fiber coal gangue powder modified rubber asphalt mortar.

[0046] Example 3

[0047] The difference between this embodiment and embodiment 1 is that the amount of polyester fiber added is different.

[0048] A method for preparing polyester fiber gangue powder modified rubber asphalt mortar specifically comprises the following steps:

[0049] 1) The gangue powder was sieved through a 0.075 mm sieve to remove large particles and other debris. The sieved gangue powder and polyester fiber were dried in an oven at 60°C for 0.5 h to remove surface moisture, and the rubber asphalt was placed in an oven at 185°C to completely melt.

[0050] 2) The rubber asphalt is mixed with coal gangue powder in a mass ratio of 1:0.6 to obtain modified rubber asphalt.

[0051] 3) The polyester fiber and the modified rubber asphalt are then mixed, and the mass ratio of the polyester fiber to the rubber asphalt is 0.005:1.

[0052] 4) The mixing temperature of the mortar is controlled at 180°C, the stirring rate is controlled at 1000 rpm, and the mixing time is 0.5h to eliminate internal bubbles in the mortar and obtain a uniform polyester fiber coal gangue powder modified rubber asphalt mortar.

[0053] Comparative Example 1

[0054] The difference between this comparative example and Example 1 is that no polyester fiber is added.

[0055] A method for preparing gangue powder modified rubber asphalt mortar specifically comprises the following steps:

[0056] 1) The gangue powder is sieved through a 0.075 mm sieve to remove large particles and other debris. The sieved gangue powder is dried in an oven at 60°C for 0.5 h to remove surface moisture, and the rubber asphalt is placed in an oven at 185°C to completely melt.

[0057] 2) Mix rubber asphalt and coal gangue powder in a mass ratio of 1:0.6 to prepare coal gangue powder rubber asphalt mortar.

[0058] 3) The mixing temperature of the mortar is controlled at 180°C, the stirring rate is controlled at 1000 rpm, and the mixing time is 0.5h to eliminate internal bubbles in the mortar and obtain a uniform coal gangue powder modified rubber asphalt mortar.

[0059] Comparative Example 2

[0060] The difference between this comparative example and Example 1 is that no polyester fiber is added, and the coal gangue powder is replaced by a mixture of coal gangue powder and limestone powder.

[0061] A method for preparing gangue powder modified rubber asphalt mortar specifically comprises the following steps:

[0062] 1) Sieve the gangue powder and limestone powder through a 0.075mm sieve to remove large particles and other debris. Dry the gangue powder and limestone powder in an oven at 60°C for 0.5h to remove surface moisture, and put the rubber asphalt into an oven at 185°C to completely melt it.

[0063] 2) Mix rubber asphalt with coal gangue powder and limestone powder in a mass ratio of 1:0.15:0.45 to prepare coal gangue powder rubber asphalt mortar.

[0064] 3) The mixing temperature of the mortar is controlled at 180°C, the stirring rate is controlled at 1000 rpm, and the mixing time is 0.5h to eliminate internal bubbles in the mortar and obtain a uniform coal gangue powder modified rubber asphalt mortar.

[0065] Comparative Example 3

[0066] The difference between this comparative example and Example 1 is: the particle size of the coal gangue powder. The particle size of the coal gangue powder used in this comparative example is 1250 mesh, which is purchased from Lingshou County Yongdeshun Mining Processing Plant.

[0067] Comparative Example 4

[0068] The difference between this comparative example and Example 1 is that the coal gangue is replaced by a mixture of silicon dioxide and aluminum oxide, the mass ratio of silicon dioxide to aluminum oxide is 3:2, wherein the particle size of silicon dioxide is 70 μm, purchased from Shanghai Xiangtian Nanomaterial Co., Ltd., model XT-SIO2-13, and the particle size of aluminum oxide is 20 μm, purchased from Shanghai Xiangtian Nanomaterial Co., Ltd., model XT-AL2O3-13.

[0069] Comparative Example 5

[0070] The difference between this comparative example and Example 1 is that the polyester fiber has a length of 15 mm, a diameter of 20 to 30 μm, a tensile strength of ≥900 MPa, an elastic modulus of 13.5 GPa, and a specific gravity of 1.36 to 1.38 kg / m 3 , melting point is 240~260℃, purchased from Shenzhen Hengyueda Building Materials Co., Ltd., model number is KLW-003.

[0071] Comparative Example 6

[0072] The difference between this comparative example and Example 1 is that the mass ratio of polyester fiber to rubber asphalt is different. In this comparative example, the mass ratio of polyester fiber to rubber asphalt is 0.01:1.

[0073] Performance Testing

[0074] The rutting factor results measured at different temperatures are shown in Table 1.

[0075] Table 1

[0076]

[0077]

[0078] Therefore, the present invention adopts a polyester fiber coal gangue powder modified rubber asphalt mortar with the above structure and a preparation method thereof. The added polyester fiber has the advantages of soft texture and high single fiber tensile strength. The addition of polyester fiber greatly improves the high temperature performance of the rubber asphalt mortar.

[0079] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that they can still modify or replace the technical solution of the present invention with equivalents, and these modifications or equivalent replacements cannot cause the modified technical solution to deviate from the spirit and scope of the technical solution of the present invention.

Claims

1. A polyester fiber gangue powder modified rubber asphalt mortar, characterized in that: The rubber asphalt mortar includes rubber asphalt, coal gangue powder and polyester fiber. The mass ratio of rubber asphalt, coal gangue powder and polyester fiber is 1:0.5~0.8:0.003~0.

005.

2. The polyester fiber gangue powder modified rubber asphalt mortar according to claim 1, characterized in that: The rubber powder content of rubber asphalt is 20%, the softening point is 65℃~70℃, the needle penetration at 25℃ is 40mm~45mm, and the elongation at 5℃ is 6.5mm~7.0mm.

3. The polyester fiber gangue powder modified rubber asphalt mortar according to claim 1, characterized in that: The specific surface area of ​​coal gangue powder is not less than 8.53m 2 / g.

4. The polyester fiber gangue powder modified rubber asphalt mortar according to claim 1, characterized in that: The length of polyester fiber is 6mm and the diameter is 10~25μm.

5. The polyester fiber gangue powder modified rubber asphalt mortar according to claim 1, characterized in that: The density of polyester fiber is 1.37g / cm 3 , tensile elastic modulus>7000MPa, tensile strength>680MPa, melting point is 260℃.

6. The method for preparing the polyester fiber gangue powder modified rubber asphalt mortar according to any one of claims 1 to 5, characterized in that: The following steps are involved: (1) The gangue powder is screened to remove large particles and debris, and the rubber asphalt is placed in an oven for melting; (2) adding the screened coal gangue powder into the melted rubber asphalt in proportion and mixing them to obtain modified rubber asphalt; (3) Add polyester fiber to modified rubber asphalt in proportion and mix evenly to obtain rubber asphalt mortar.

7. The method for preparing a polyester fiber gangue powder modified rubber asphalt mortar according to claim 6, characterized in that: In step (1), the gangue powder is sieved through a 0.075 mm sieve.

8. The method for preparing a polyester fiber gangue powder modified rubber asphalt mortar according to claim 6, characterized in that: The gangue powder in step (1) is sieved and then dried at 55-65° C. for 0.5-2 h to remove excess moisture; the polyester fiber in step (3) is dried at 55-65° C. for 0.5-2 h to remove excess moisture.

9. The method for preparing a polyester fiber gangue powder modified rubber asphalt mortar according to claim 6, characterized in that: The melting temperature of the rubber asphalt in step (1) is 180-190°C.

10. The method for preparing a polyester fiber gangue powder modified rubber asphalt mortar according to claim 6, characterized in that: The mixing temperature in step (2) and step (3) is 175-185° C., the mixing stirring rate is 800-1200 r / min, and the mixing time is 0.5-3 h to eliminate internal bubbles in the mortar.

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