Fly ash aeolian sand roadbed filling material and preparation method thereof

Abstract

The invention relates to a preparation method of a fly ash aeolian sand roadbed filling material, the material comprises fly ash, aeolian sand and water, the fly ash and the aeolian sand are uniformly mixed to obtain a mixture of the fly ash and the aeolian sand, the water with a certain mass ratio is added into the mixture, and the mixture is fully stirred to obtain the aeolian sand roadbed filling material. The fly ash and the aeolian sand are mixed on site, local materials are used, the transfer link is reduced, the fly ash polluting the atmosphere is fully utilized, and the method is economical, environmentally friendly and easy to operate; the fly ash and water are subjected to a hydration reaction to generate a gel substance, and the aeolian sand which is a material with a single particle size and poor integrality is agglomerated and formed to form the road building material with relatively high strength and integrality.

Description

Technical Field

[0001] The invention belongs to the technical field of highway construction, and in particular relates to a fly ash aeolian sand roadbed filling material and a preparation method thereof. Background Art

[0002] Article 5.1.2 of the Guidelines for Design and Construction of Highways in Desert Areas states that: "Since aeolian sand has the characteristics of water stability, easy vibration compaction, and high overall compressive strength, it should be fully utilized as a roadbed material", indicating that aeolian sand is a good roadbed filling material and should be fully utilized locally. Article 5.1.3 of the Guidelines for Design and Construction of Highways in Desert Areas states that: "Necessary measures should be taken to reinforce the aeolian sand roadbed, shoulders and slopes to avoid or reduce vehicle sinking and wind erosion, and ensure the overall stability of the highway and driving safety." This shows that the characteristics of aeolian sand are single particle size and lack of cohesion, and its exposed interface should be reinforced in the design. Article 5.1.5 of the Guidelines for Design and Construction of Highways in Desert Areas states that: "A geotextile reinforcement layer or sealing layer should be set on the top of the desert roadbed", which also shows that aeolian sand lacks cohesion and has poor integrity, which can easily cause the upper road construction materials to invade each other under external loads, resulting in potholes, subsidence and other diseases on the road surface.

[0003] The current aeolian sand roadbed filling materials require a large amount of binders, coal gangue, plant fibers and other materials, which are not only economical but also difficult to operate. Therefore, how to solve the above problems has become the focus of research. Summary of the invention

[0004] In view of the shortcomings of the prior art, the present invention provides a fly ash aeolian sand roadbed filling material and a preparation method thereof.

[0005] To achieve the above object, the present invention provides the following technical solutions:

[0006] A fly ash and aeolian sand roadbed filling material comprises fly ash, aeolian sand and water.

[0007] A method for preparing fly ash aeolian sand roadbed filling material comprises the following steps:

[0008] 1) mixing fly ash and aeolian sand to obtain a mixture of fly ash and aeolian sand;

[0009] 2) adding water to the mixture of fly ash and aeolian sand, and stirring to obtain fly ash aeolian sand roadbed filling material.

[0010] Furthermore, the mass ratio of fly ash and aeolian sand in step 1) is (30-50):(50-70).

[0011] Furthermore, the mass ratio of fly ash and aeolian sand in step 1) is (40-48):(52-60).

[0012] Furthermore, in step 2), the water is 5-10% of the mass of the mixture of fly ash and aeolian sand.

[0013] Furthermore, in step 2), the water is 6-8% of the mass of the mixture of fly ash and aeolian sand.

[0014] The fly ash aeolian sand roadbed filling material is prepared according to the above preparation method.

[0015] Compared with the prior art, the present invention has the following beneficial effects:

[0016] 1) The present invention provides a fly ash and aeolian sand roadbed filling material and a preparation method thereof. The material is made of fly ash, aeolian sand and water. Under the background of the country vigorously advocating carbon peak, fly ash, an industrial solid waste, has the characteristics of difficult treatment, great environmental harm and serious secondary pollution. Aeolian sand is generally concentrated near the aeolian sand roadbed. The present invention mixes aeolian sand with fly ash and water on-site, and the fly ash is directly made into roadbed filling material after production. It is most economical to use local materials. On-site mixing reduces the transportation link, solves the solid waste treatment problem, and reduces air pollution.

[0017] 2) The fly ash aeolian sand roadbed filling material of the present invention generates a gel substance through the hydration reaction of fly ash, and condenses the aeolian sand, a material with a single particle size and poor integrity, to form a road construction material with high strength and integrity, so as to achieve the effect of improving the defects of the aeolian sand roadbed, making it have good integrity, good cohesion, high stability, and reducing the engineering of exposed surface reinforcement and upper sealing layer. The strength of the aeolian sand roadbed made with the material meets the various technical requirements of the "Highway Roadbed Design Code".

[0018] 3) The preparation method of the fly ash and aeolian sand roadbed filling material of the present invention is that the material is formed by uniformly mixing aeolian sand, fly ash and water. Compared with the materials of the prior art, the material used in the present invention has low cost, high economy and low construction difficulty. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the specific embodiments of the present invention, the drawings required for use in the specific embodiments or the description of the prior art will be briefly introduced below.

[0020] Figure 1 It is a performance test result curve diagram of the rebound modulus of embodiments 1 to 3 of the present invention;

[0021] Figure 2 The performance test result curve diagram of CBR of embodiments 1 to 3 of the present invention;

[0022] Figure 3 It is a performance test result curve diagram of the unconfined compressive strength of Examples 1 to 3 of the present invention. DETAILED DESCRIPTION

[0023] The invention relates to a fly ash aeolian sand roadbed filling material and a preparation method thereof. The raw materials used are fly ash, aeolian sand and water. The active components in the fly ash undergo hydration reaction upon contact with water to generate a gel substance, which can aggregate and shape the aeolian sand particles therein, thereby improving the integrity and strength of the aeolian sand roadbed.

[0024] Sources:

[0025] Fly ash: taken from the large-scale coal, coal-fired power and coal chemical industry demonstration zone in Xinjiang Zhundong Economic and Technological Development Zone, with a particle size range of 0.5 to 300 μm.

[0026] Aeolian sand: taken from the Gurbantunggut Desert, with a particle size range of 0.074-0.250 mm, aeolian sand content ≥ 90%, and a maximum dry density of 1.8-2.0 g / cm after compaction 3 .

[0027] Embodiment 1

[0028] The method for preparing the fly ash aeolian sand roadbed filling material of the present invention comprises the following steps:

[0029] 1) Mixing fly ash and aeolian sand in a mass ratio of 30:70 to obtain a mixture of fly ash and aeolian sand;

[0030] 2) adding water to the mixture of fly ash and aeolian sand, stirring to obtain fly ash aeolian sand roadbed filling material, the fly ash and water undergo hydration reaction to form a gel, wherein the water accounts for 9% of the mass of the mixture of fly ash and aeolian sand.

[0031] Embodiment 2

[0032] The method for preparing the fly ash aeolian sand roadbed filling material of the present invention comprises the following steps:

[0033] 1) Mixing fly ash and aeolian sand in a mass ratio of 40:60 to obtain a mixture of fly ash and aeolian sand;

[0034] 2) adding water to the mixture of fly ash and aeolian sand, stirring to obtain fly ash aeolian sand roadbed filling material, the fly ash and water undergo hydration reaction to form a gel, wherein the water accounts for 7% of the mass of the mixture of fly ash and aeolian sand.

[0035] Embodiment 3

[0036] The method for preparing the fly ash aeolian sand roadbed filling material of the present invention comprises the following steps:

[0037] 1) Mixing fly ash and aeolian sand in a mass ratio of 45:55 to obtain a mixture of fly ash and aeolian sand;

[0038] 2) adding water to the mixture of fly ash and aeolian sand, stirring to obtain fly ash aeolian sand roadbed filling material, the fly ash and water undergo hydration reaction to form a gel, wherein the water accounts for 6.5% of the mass of the mixture of fly ash and aeolian sand.

[0039] Performance Testing

[0040] This example also tests the modulus of resilience, CBR (California Bearing Ratio Test), and unconfined compressive strength of Examples 1 to 3 with the introduction of aeolian sand (blank control). The test results are shown in Table 1.

[0041] Table 1 Performance test results of Examples 1 to 3 and blank control

[0042]

[0043] Figures 1 to 3 The following are the test results of the resilience modulus, CBR (California bearing ratio test), and unconfined compressive strength of Examples 1 to 3 and the blank control. From Table 1, Figures 1 to 3 It can be seen from the results that the fly ash aeolian sand roadbed filling material prepared by the method of the present invention has much greater rebound modulus, CBR and unconfined compressive strength than the blank control group in Examples 1 to 3, and the performance becomes stronger from Examples 1 to 3, among which Example 3 has the best effect.

[0044] The above shows and describes the basic principles and main features of the present invention and the advantages of the present invention. It is obvious to those skilled in the art that the present invention is not limited to the details of the above exemplary embodiments. On the basis of the present invention, some modifications or improvements can be made thereto, which is obvious to those skilled in the art. Therefore, these modifications or improvements made on the basis of not departing from the spirit of the present invention all belong to the scope of protection claimed by the present invention.

Claims

1. A fly ash aeolian sand roadbed filling material, characterized in that: Including fly ash, aeolian sand and water.

2. A method for preparing the fly ash aeolian sand roadbed filling material according to claim 1, characterized in that: The following steps are involved: 1) mixing fly ash and aeolian sand to obtain a mixture of fly ash and aeolian sand; 2) adding water to the mixture of fly ash and aeolian sand, and stirring to obtain fly ash aeolian sand roadbed filling material.

3. The preparation method according to claim 2, characterized in that: The mass ratio of fly ash and aeolian sand in step 1) is (30-50):(50-70).

4. The preparation method according to claim 3, characterized in that: The mass ratio of fly ash and aeolian sand in step 1) is (40-48):(52-60).

5. The preparation method according to claim 3 or 4, characterized in that: In step 2), the water is 5-10% of the mass of the mixture of fly ash and aeolian sand.

6. The preparation method according to claim 5, characterized in that: In step 2), the water is 6-8% of the mass of the mixture of fly ash and aeolian sand.

7. The fly ash aeolian sand roadbed filling material prepared by the preparation method according to any one of claims 2 to 6.

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