Concrete for road construction and preparation method thereof
By modifying polypropylene fibers with polyvinyl butyral and magnesium oxide, the problem of fibers being easily aggregated and difficult to disperse evenly is solved, and the compressive strength of concrete is significantly improved.
Patent Information
- Application Number
- CN202510160788.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-02-13
- Publication Date
- 2025-05-06
AI Technical Summary
In the process of using polypropylene fiber to increase the strength of concrete, the fibers are prone to aggregate and difficult to disperse evenly, resulting in a lower concrete strength.
The surface modification of the polypropylene fibers by using polyvinyl butyral and magnesium oxide can improve the dispersion effect and bonding performance of the fibers, thereby improving the strength of the concrete.
The reinforcement effect of polypropylene fiber in concrete has been significantly improved, and the compressive strength of concrete has been improved, making it reach more than 50MPa.
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Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of concrete, and in particular to concrete for road construction and a preparation method thereof. Background Art
[0002] In modern road construction projects, concrete is undoubtedly the core material for road paving, and its importance is self-evident. At present, traffic volume is showing a trend of continuous increase, vehicle load is constantly breaking records, and the service environment of roads is becoming more and more complex and changeable. Under such a background, the requirements for concrete strength in road construction have also reached a new height.
[0003] As a fiber-reinforced material, polypropylene fiber has been widely used due to its light weight, high strength and excellent tensile properties. However, in the process of using polypropylene fiber to improve the strength of concrete, the fiber is often prone to agglomeration and difficult to disperse evenly. This drawback seriously weakens the strengthening effect of polypropylene fiber on the strength of concrete. In view of this, it is of great significance to improve the strength of concrete containing polypropylene fibers. Summary of the invention
[0004] The invention provides concrete for road construction and a preparation method thereof, which solves the problem of low strength of concrete containing polypropylene fibers in the related art.
[0005] The technical solution of the present invention is as follows: The present invention provides a concrete for road construction, wherein the raw materials include the following components in parts by weight: 100 parts of cement, 20-40 parts of fly ash, 150-250 parts of river sand, 200-300 parts of basalt, 50-55 parts of polypropylene fiber reinforcement, and 60-80 parts of water; The raw materials of the polypropylene fiber reinforcement include polypropylene fiber, polyvinyl butyral and magnesium oxide in a weight ratio of 48:1 to 6:1.
[0006] As a further technical solution, the preparation method of the polypropylene fiber reinforcement comprises the following steps: dissolving polyvinyl butyral in ethanol, adding polypropylene fiber and magnesium oxide, dispersing evenly, and drying to obtain the polypropylene fiber reinforcement.
[0007] As a further technical solution, the polyvinyl butyral includes a first polyvinyl butyral and a second polyvinyl butyral, and the weight average molecular weight of the first polyvinyl butyral is smaller than the weight average molecular weight of the second polyvinyl butyral.
[0008] In the present invention, the inventors found that when two polyvinyl butyrals with different weight average molecular weights are used for modification, the strength of concrete can be further improved. It is speculated that the use of two polyvinyl butyrals with different weight average molecular weights can further improve the coating modification effect, thereby further improving the strength of concrete.
[0009] As a further technical solution, the weight average molecular weight of the first polyvinyl butyral is 15,000-27,000, and the weight average molecular weight of the second polyvinyl butyral is 92,000-130,000.
[0010] In the present invention, when the weight average molecular weight of the first polyvinyl butyral is 15000-27000 and the weight average molecular weight of the second polyvinyl butyral is 92000-130000, it helps to further improve the strength of the concrete.
[0011] As a further technical solution, the weight of the first polyvinyl butyral is greater than the weight of the second polyvinyl butyral.
[0012] In the present invention, when the weight of the first polyvinyl butyral is greater than the weight of the second polyvinyl butyral, it helps to further improve the strength of the concrete.
[0013] As a further technical solution, the weight ratio of the first polyvinyl butyral to the second polyvinyl butyral is 2-3:1.
[0014] As a further technical solution, the particle size of the fly ash is 10-50 μm.
[0015] As a further technical solution, the particle size of the river sand is 0.5~2mm.
[0016] As a further technical solution, the particle size of the basalt is 4-6 mm.
[0017] In the present invention, by designing the particle sizes of fly ash, river sand and basalt, the packing density can be increased, the voids can be reduced, the amount of cement in the concrete can be reduced, and the cost can be saved.
[0018] As a further technical solution, the raw materials further include 4 to 6 parts of a water reducing agent; The water reducer is a polycarboxylate water reducer or a naphthalene water reducer.
[0019] In the present invention, the addition of the water reducing agent can improve the fluidity of the concrete and help the concrete maintain good working performance.
[0020] As a further technical solution, the raw materials also include 2 to 4 parts of antifreeze; The antifreeze agent includes one or both of calcium nitrite and sodium nitrite.
[0021] In the present invention, the addition of antifreeze can prevent concrete from being unable to harden normally due to freezing.
[0022] The present invention also provides a method for preparing the concrete for road construction, comprising the following steps: mixing the components evenly to obtain the concrete for road construction.
[0023] The working principle and beneficial effects of the present invention are: In the present invention, polypropylene fibers are treated with polyvinyl butyral and magnesium oxide, which, on the one hand, improves the hydrophilicity of the surface of the polypropylene fibers and enhances the dispersion effect of the polypropylene fibers in concrete, thereby greatly improving the strengthening effect of the polypropylene fibers; on the other hand, changes the roughness of the surface of the polypropylene fibers, enhances the bonding performance between the polypropylene fibers and the cement matrix, and thus significantly improves the strength of the concrete. DETAILED DESCRIPTION
[0024] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.
[0025] In the following embodiments and comparative examples, unless otherwise specified, cement is silicate cement, model PO42.5; the particle size of fly ash is 30 μm; the particle size of river sand is 1 mm; the particle size of basalt is 5 mm; the polypropylene fiber is a bundled monofilament with a diameter of 2.5 μm, a length of 3 mm, and a tensile strength of 360 MPa, purchased from Tuoda (Shandong) New Materials Technology Industry; the particle size of magnesium oxide is 6 μm; the model of polycarboxylic acid water reducer is SP-409; and the model of naphthalene water reducer is FDN-A.
[0026] Example 1 A method for preparing concrete for road construction comprises the following steps: mixing 100 parts of cement, 20 parts of fly ash, 150 parts of river sand, 200 parts of basalt, 50 parts of polypropylene fiber reinforcement, 4 parts of polycarboxylate water reducer, 2 parts of calcium nitrite and 60 parts of water uniformly by weight to obtain concrete for road construction; The preparation method of the polypropylene fiber reinforcement comprises the following steps: dissolving 1 part of polyvinyl butyral (model S-LEC BL-10, weight average molecular weight 15000) in 100 parts of ethanol, adding 48 parts of polypropylene fiber and 1 part of magnesium oxide, dispersing evenly, and drying to obtain the polypropylene fiber reinforcement.
[0027] Example 2 A method for preparing concrete for road construction comprises the following steps: mixing 100 parts of cement, 40 parts of fly ash, 250 parts of river sand, 300 parts of basalt, 55 parts of polypropylene fiber reinforcement, 6 parts of naphthalene water reducing agent, 4 parts of sodium nitrite and 80 parts of water uniformly by weight to obtain concrete for road construction; The preparation method of the polypropylene fiber reinforcement comprises the following steps: dissolving 6 parts of polyvinyl butyral (model S-LEC BL-10, weight average molecular weight 15000) in 100 parts of ethanol, adding 48 parts of polypropylene fiber and 1 part of magnesium oxide, dispersing evenly, and drying to obtain the polypropylene fiber reinforcement.
[0028] Example 3 The only difference between this embodiment and embodiment 2 is that in this embodiment, the model of polyvinyl butyral is S-LECBM-1, and the weight average molecular weight is 40,000.
[0029] Example 4 The only difference between this embodiment and embodiment 2 is that in this embodiment, the model of polyvinyl butyral is S-LECBH-6, and the weight average molecular weight is 92,000.
[0030] Example 5 The only difference between this embodiment and embodiment 2 is that, in this embodiment, polyvinyl butyral includes 3 parts of a first polyvinyl butyral (model S-LEC BL-10, weight average molecular weight of 15000) and 3 parts of a second polyvinyl butyral (model S-LEC BM-1, weight average molecular weight of 40000).
[0031] Example 6 The only difference between this embodiment and embodiment 2 is that, in this embodiment, polyvinyl butyral includes 3 parts of a first polyvinyl butyral (model S-LEC BM-1, weight average molecular weight of 40,000) and 3 parts of a second polyvinyl butyral (S-LECBH-6, weight average molecular weight of 92,000).
[0032] Example 7 The only difference between this embodiment and embodiment 2 is that, in this embodiment, the polyvinyl butyral includes 3 parts of a first polyvinyl butyral (model S-LEC BL-10, weight average molecular weight of 15000) and 3 parts of a second polyvinyl butyral (S-LEC BH-6, weight average molecular weight of 92000).
[0033] Example 8 The only difference between this embodiment and Embodiment 7 is that, in this embodiment, the weight portion of the first polyvinyl butyral is 1.5 parts, and the weight portion of the second polyvinyl butyral is 4.5 parts.
[0034] Example 9 The only difference between this embodiment and Embodiment 7 is that, in this embodiment, the weight portion of the first polyvinyl butyral is 4.5 parts, and the weight portion of the second polyvinyl butyral is 1.5 parts.
[0035] Example 10 The only difference between this embodiment and Embodiment 7 is that, in this embodiment, the weight portion of the first polyvinyl butyral is 4 parts, and the weight portion of the second polyvinyl butyral is 2 parts.
[0036] Embodiment 11 The only difference between this embodiment and embodiment 10 is that in this embodiment, the model of the first polyvinyl butyral is S-LEC BL-2, and the weight average molecular weight is 27,000; the model of the second polyvinyl butyral is S-LEC BX-5, and the weight average molecular weight is 130,000.
[0037] Comparative Example 1 The only difference between this comparative example and Example 1 is that in this comparative example, the polypropylene fiber reinforcement material is replaced with an equal amount of polypropylene fibers.
[0038] Comparative Example 2 The only difference between this comparative example and Example 1 is that in this comparative example, the preparation method of the polypropylene fiber reinforcement comprises the following steps: dissolving 2 parts of polyvinyl butyral (model S-LEC BL-10, weight average molecular weight 15000) in 100 parts of ethanol, adding 48 parts of polypropylene fibers, dispersing evenly, and drying to obtain a polypropylene fiber reinforcement.
[0039] Comparative Example 3 The only difference between this comparative example and Example 1 is that in this comparative example, the method for preparing the polypropylene fiber reinforcement material comprises the following steps: 2 parts of magnesium oxide and 48 parts of polypropylene fibers are uniformly mixed to obtain the polypropylene fiber reinforcement material.
[0040] Comparative Example 4 The only difference between this comparative example and Example 1 is that in this comparative example, the preparation method of the polypropylene fiber reinforcement includes the following steps: 1 part of magnesium oxide and 1 part of styrene acrylic emulsion (Resda R-910A) are evenly mixed to obtain a slurry, the slurry is evenly sprayed on the surface of 48 parts of polypropylene fibers, and dried to obtain a polypropylene fiber reinforcement.
[0041] Comparative Example 5 A method for preparing concrete for road construction comprises the following steps: by weight, 100 parts of cement, 20 parts of fly ash, 150 parts of river sand, 200 parts of basalt, 48 parts of polypropylene fiber, 1 part of polyvinyl butyral (model S-LECBL-10, weight average molecular weight of 15000), 1 part of magnesium oxide, 4 parts of polycarboxylate water reducer, 2 parts of calcium nitrite and 60 parts of water are uniformly mixed to obtain concrete for road construction.
[0042] The road construction concrete prepared in Examples 1 to 11 and Comparative Examples 1 to 5 was cured and tested for compressive strength according to the curing method of the specimen in GB / T 50081-2019 "Standard for Test Methods for Physical and Mechanical Properties of Concrete", and the curing age was 28 days: When testing the compressive strength, the loading speed was 0.8 MPa / s, and the test average value of 3 specimens (150 mm cubes) was taken as the final result; The test results are shown in Table 1 below.
[0043] Table 1 Test results of concrete strength for road construction
[0044] Comparison between Example 1 and Comparative Examples 1 to 5 shows that surface modification of polypropylene fibers by polyvinyl butyral and magnesium oxide can significantly improve the strength of concrete for road construction, making its compressive strength reach above 50 MPa.
[0045] Comparison between Examples 2 to 4 and Examples 5 to 11 shows that when two polyvinyl butyrals with different weight average molecular weights are used for modification, the strength of concrete for road construction can be further improved, and the compressive strength thereof can reach above 55 MPa.
[0046] Comparison of Examples 5-6 and Examples 7-10 shows that when the weight average molecular weight of the first polyvinyl butyral is 15000-27000 and the weight average molecular weight of the second polyvinyl butyral is 92000-130000, it helps to further improve the strength of concrete for road construction and make its compressive strength reach above 60 MPa.
[0047] Comparison between Examples 7-8 and Examples 9-10 shows that when the weight of the first polyvinyl butyral (weight average molecular weight of 15,000-27,000) is greater than the weight of the second polyvinyl butyral (weight average molecular weight of 92,000-130,000), it helps to further improve the strength of the concrete and make its compressive strength reach above 65 MPa.
[0048] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.
Claims
1. A concrete for road construction, characterized in that: The raw materials include the following components in parts by weight: 100 parts of cement, 20-40 parts of fly ash, 150-250 parts of river sand, 200-300 parts of basalt, 50-55 parts of polypropylene fiber reinforcement, and 60-80 parts of water; The raw materials of the polypropylene fiber reinforcement include polypropylene fiber, polyvinyl butyral and magnesium oxide in a weight ratio of 48:1 to 6:
1.
2. A road construction concrete according to claim 1, characterized in that: The preparation method of the polypropylene fiber reinforcement comprises the following steps: dissolving polyvinyl butyral in ethanol, adding polypropylene fiber and magnesium oxide, dispersing evenly, and drying to obtain the polypropylene fiber reinforcement.
3. The road construction concrete according to claim 1, characterized in that: The polyvinyl butyral includes a first polyvinyl butyral and a second polyvinyl butyral, and a weight average molecular weight of the first polyvinyl butyral is smaller than a weight average molecular weight of the second polyvinyl butyral.
4. A road construction concrete according to claim 3, characterized in that: The weight average molecular weight of the first polyvinyl butyral is 15,000-27,000, and the weight average molecular weight of the second polyvinyl butyral is 92,000-130,000.
5. The road construction concrete according to claim 3, characterized in that: The weight of the first polyvinyl butyral is greater than the weight of the second polyvinyl butyral.
6. The road construction concrete according to claim 5, characterized in that: The weight ratio of the first polyvinyl butyral to the second polyvinyl butyral is 2-3:
1.
7. The road construction concrete according to any one of claims 1 to 6, characterized in that: The particle size of the fly ash is 10-50 μm; and / or The particle size of the river sand is 0.5-2 mm; and / or The particle size of the basalt is 4-6 mm.
8. The road construction concrete according to any one of claims 1 to 6, characterized in that: The raw materials also include 4 to 6 parts of a water reducing agent; The water reducer is a polycarboxylate water reducer or a naphthalene water reducer.
9. The road construction concrete according to any one of claims 1 to 6, characterized in that: The raw materials also include 2 to 4 parts of antifreeze; The antifreeze agent includes one or both of calcium nitrite and sodium nitrite.
10. The method for preparing concrete for road construction according to claim 1, characterized in that: The method comprises the following steps: mixing the components uniformly to obtain the concrete for road construction.