High-performance concrete and preparation method thereof

Abstract

The invention discloses high-performance concrete and a preparation method thereof, and belongs to the technical field of concrete, and the high-performance concrete is prepared from the following components in parts by mass: 3.51 to 3.93 parts of cement, 37.01 to 38.73 parts of machine-made sand, 21.78 to 22.71 parts of gravel, 5.55 parts of water, 0.088 to 0.099 part of PCA-I polycarboxylic acid high-performance water reducing agent, 1.17 to 1.32 parts of S75-grade superfine slag powder and 1.17 to 1.32 parts of fly ash. The concrete obtained according to the technical scheme recorded by the invention is relatively high in slump and good in flowability, can meet the requirement of highway drilling grouting design strength, and can also meet the flowability and initial setting time required by long-distance transportation construction of grout.

Description

Technical Field

[0001] The present invention belongs to the technical field of concrete, and in particular relates to high performance concrete and a preparation method thereof. Background Art

[0002] Cement and fly ash grouting are used in commercial concrete in certain quantities. The mix ratios specified for grouting in the highway industry require a significant amount of cement, resulting in high material costs per cubic meter. High early strength is required, and the grouting mixture should exhibit good cohesion, high fluidity, and minimal shrinkage. Furthermore, the grouting process should be free of segregation and water seepage, and the grouting setting time should be delayed, among other engineering parameters. A high cement content results in a correspondingly high heat of hydration, resulting in a certain degree of autogenous shrinkage, which can negatively impact durability.

[0003] In order to achieve high fluidity in cement and fly ash drilling grouting, a considerable amount of cement is used, and the corresponding hydration heat is high. In addition, the transportation distance is long, which makes it difficult to meet construction requirements, and the economic cost of the grouting materials is high. Summary of the Invention

[0004] In order to overcome the problems existing in the prior art, the present invention provides a high performance concrete and a preparation method thereof.

[0005] To achieve the above object, the present invention is implemented through the following technical solutions: A high-performance concrete comprises the following components in parts by weight: 3.51-3.93 parts of cement, 37.01-38.73 parts of machine-made sand, 21.78-22.71 parts of crushed stone, 5.55 parts of water, 0.088-0.099 parts of PCA-I polycarboxylate high-performance water reducer, 1.17-1.32 parts of S75 grade slag powder, and 1.17-1.32 parts of fly ash.

[0006] Furthermore, it contains the following components in parts by mass: 3.72 parts of cement, 37.92 parts of machine-made sand, 22.62 parts of crushed stone, 5.55 parts of water, 0.093 parts of PCA-I polycarboxylic acid high-performance water-reducing agent, 1.23 parts of S75 grade slag powder, and 1.23 parts of fly ash.

[0007] Furthermore, the cement is ordinary Portland 42.5 cement.

[0008] Furthermore, the machine-made sand contains 0.3% mud and has a fineness modulus of 2.9.

[0009] Furthermore, the crushed stone has a crushing value of 11%, a mud content of 0.1%, a gradation range of 5-31.5, and a needle-like particle content of 2.1%.

[0010] Through the above technical solution, the present invention can at least achieve the following beneficial effects: the concrete obtained according to the technical solution recorded in the present invention has a high slump and good fluidity. Although the strength on the third and seventh days is lower than that of the comparative example 1, after 14 days, the strength of the concrete blocks of Examples 1 to 3 and Comparative Example 1 is not much different, which can meet the design strength requirements of highway drilling grouting, and can also meet the fluidity and initial setting time requirements for long-distance transportation of slurry. DETAILED DESCRIPTION

[0011] Unless otherwise stated, all materials and reagents used in the present invention are commercially available.

[0012] The cement used in the present invention was purchased from Yunnan Yuandong Cement Co., Ltd. and was PO 42.5 cement. The machine-made sand was purchased from Zhanyi Zhongtian Stone Co., Ltd., with a mud content of 0.3% and a fineness modulus of 2.9; The crushed stone was purchased from Zhanyi Zhongtian Stone Co., Ltd., with a crushing value of 11%, a mud content of 0.1%, a gradation range of 5-31.5, and a needle-like particle content of 2.1%; PCA-I polycarboxylate high-performance water reducer was purchased from Jiangsu Subote New Materials Co., Ltd.; S75 grade slag powder was purchased from Qujing Xin Innovation Materials Co., Ltd.; Fly ash was purchased from Malong County Yaowen Trading Co., Ltd.

[0013] In the following embodiments, the method for preparing concrete is as follows: S1, dry-mixing cement, machine-made sand, crushed stone, S75 grade slag powder and fly ash to obtain a first mixture; S2, adding water and PCA-I polycarboxylate high performance water reducer to the first mixture, mixing well to obtain concrete.

[0014] Example 1 A high-performance concrete comprises the following components in parts by weight: 3.51 parts of cement, 38.73 parts of machine-made sand, 21.78 parts of crushed stone, 5.55 parts of water, 0.088 parts of PCA-I polycarboxylate high-performance water-reducing agent, 1.17 parts of S75 grade slag powder, and 1.17 parts of fly ash.

[0015] Example 2 A high-performance concrete comprises the following components in parts by weight: 3.72 parts of cement, 37.92 parts of machine-made sand, 22.62 parts of crushed stone, 5.55 parts of water, 0.093 parts of PCA-I polycarboxylate high-performance water-reducing agent, 1.23 parts of S75 grade slag powder, and 1.23 parts of fly ash.

[0016] Example 3 A high-performance concrete comprises the following components in parts by weight: 3.93 parts of cement, 37.01 parts of machine-made sand, 22.71 parts of crushed stone, 5.55 parts of water, 0.099 parts of PCA-I polycarboxylate high-performance water-reducing agent, 1.32 parts of S75 grade slag powder, and 1.32 parts of fly ash.

[0017] Comparative Example 1 The difference between Comparative Example 1 and Example 1 is that S75 grade slag powder is not added.

[0018] Test example The workability, slump, and spread of the concrete prepared according to the technical solutions described in Examples 1 to 3 and Comparative Example 1 were tested, as well as the 7 / 28 day compressive strength of the concrete test blocks. The results are shown in Table 1 below.

[0019] Table 1 Statistics of workability, slump, diffusion and 3 / 7 / 14-day compressive strength of concrete specimens obtained from each treatment As can be seen from Table 1, the concrete prepared in Examples 1 to 3 of the present invention has a high slump and good fluidity. Although the strength on the third and seventh days is lower than that of Comparative Example 1, the strength difference between the concrete test blocks of Examples 1 to 3 and Comparative Example 1 is not much after 14 days, which can meet the design strength requirements of highway drilling grouting and can also meet the fluidity and initial setting time requirements for long-distance transportation of slurry.

[0020] At the same time, the addition of S75 grade slag powder to replace part of the cement in the grouting can reduce the water consumption and cement consumption, lower the water-cement ratio and reduce the hydration heat while maintaining the fluidity and strength design requirements of the original drilling grouting slurry. At the same time, after the addition of S75 grade slag powder, a significant "stone rate" effect is produced in the grouting, which effectively restrains the shrinkage of the drilling grouting slurry itself, thereby improving the overall fluidity and density of the slurry.

[0021] Finally, it should be noted that the above preferred embodiments are only used to illustrate the technical solutions of the present invention and are not limiting. Although the present invention has been described in detail through the above preferred embodiments, those skilled in the art should understand that various changes can be made in form and details without departing from the scope defined by the claims of the present invention.

Claims

1. A high performance concrete, characterized by: The invention comprises the following components in parts by mass: 3.51-3.93 parts of cement, 37.01-38.73 parts of machine-made sand, 21.78-22.71 parts of crushed stone, 5.55 parts of water, 0.088-0.099 parts of PCA-I polycarboxylic acid high-performance water-reducing agent, 1.17-1.32 parts of S75 grade slag powder, and 1.17-1.32 parts of fly ash.

2. The high performance concrete according to claim 1, characterized in that: The mixture comprises the following components in parts by mass: 3.72 parts of cement, 37.92 parts of machine-made sand, 22.62 parts of crushed stone, 5.55 parts of water, 0.093 parts of PCA-I polycarboxylic acid high-performance water-reducing agent, 1.23 parts of S75 grade slag powder, and 1.23 parts of fly ash.

3. The high performance concrete according to claim 1, characterized in that: The cement is ordinary Portland 42.5 cement.

4. The high performance concrete according to claim 1, characterized in that: The machine-made sand contains 0.3% mud and has a fineness modulus of 2.

9.

5. The high performance concrete according to claim 1, characterized in that: The crushed stone has a crushing value of 11%, a mud content of 0.1%, a gradation range of 5-31.5, and a needle-like particle content of 2.1%.

6. The method for preparing concrete according to any one of claims 1 to 5, characterized in that: The following steps are included: S1, dry-mixing cement, machine-made sand, crushed stone, S75 grade slag powder and fly ash to obtain a first mixture; S2, adding water and PCA-I polycarboxylate high performance water reducer to the first mixture, mixing well to obtain concrete.

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