Mortar for inhibiting alkali activity of Yinan rock aggregate as well as preparation method and application of mortar

Abstract

The invention belongs to the technical field of building materials, and particularly relates to mortar for inhibiting alkali activity of Yinan rock aggregate as well as a preparation method and application of the mortar. The mortar for inhibiting the alkali activity of the Yinan rock aggregate is prepared from the following raw materials in percentage by weight: 12.1 to 17.5 percent of cement, 6.7 percent of Yinan rock, 2.7 to 8.1 percent of fly ash, 60.5 percent of artificial sand and the balance of water. The mortar has the beneficial effects that the mortar for inhibiting the alkali activity of the Yinan rock aggregate can effectively inhibit the alkali activity of the Yinan rock aggregate, and the problem of insufficient supply of coal ash in water-power engineering in a Tibetan area is solved.

Description

Technical Field

[0001] The present invention belongs to the technical field of building materials, and particularly relates to a mortar for inhibiting the alkali activity of dacite aggregate, a preparation method thereof, and an application thereof. Background Art

[0002] Cement and water form cement paste, and the cement paste wraps the sand to form cement mortar. Before the concrete hardens, the cement mortar plays a lubricating role, endows the concrete mixture with a certain fluidity, wraps the surface of the coarse aggregate and fills its voids. After the cement paste hardens, it binds the sand and stone aggregates into a solid whole.

[0003] An alkali-active aggregate refers to an aggregate that will chemically react with alkali substances in cement, admixtures, and mineral admixtures in concrete under certain conditions. This reaction may cause the volume expansion and even cracking of the concrete, change the microstructure of the concrete, and cause significant decline in mechanical properties such as the compressive strength and flexural strength of the concrete. That is, the alkali-aggregate activity is an important factor affecting the durability of concrete. Therefore, inhibiting the harm of alkali-aggregate activity is of great significance for improving the performance of concrete. Summary of the Invention

[0004] The present application provides a mortar for inhibiting the alkali activity of dacite aggregate, a preparation method thereof, and an application thereof, aiming to solve the problem of alkali activity in concrete using dacite aggregate in hydropower projects in Tibetan areas.

[0005] The first aspect of the present application provides a mortar for inhibiting the alkali activity of dacite aggregate, comprising raw materials in the following weight percentages: 12.1%-17.5% of cement, 6.7% of dacite, 2.7%-8.1% of fly ash, 60.5% of manufactured sand, and the balance being water.

[0006] According to some embodiments of the mortar for inhibiting the alkali activity of dacite aggregate of the present application, the cement is Portland 42.5 cement or ordinary Portland 42.5 cement, and the fineness of the cement is 300-350m 2 / kg.

[0007] According to some embodiments of the mortar for inhibiting the alkali activity of dacite aggregate of the present application, the manufactured sand is manufactured sand ground from dacite aggregate, and the fineness of the manufactured sand is 2.4-2.8 mesh.

[0008] According to some embodiments of the mortar for inhibiting the alkali activity of dacite aggregate of the present application, the particle fineness of the dacite is such that the residue on a 45μm square hole sieve is 10%-20%.

[0009] According to some embodiments of the mortar for inhibiting the alkali activity of dacite aggregate of the present application, the fly ash grade is Class F II, and the particle fineness of the fly ash is such that the residue on a 45μm square hole sieve is 15%-25%.

[0010] According to some embodiments of the mortar for suppressing the alkali-activity of andesite aggregate described in the present application, the alkali-activity of the mortar is such that the expansion rate of the 28-day mortar specimen is less than 0.10%.

[0011] The second aspect of the present application provides a method for preparing the mortar for suppressing the alkali-activity of andesite aggregate described in the first aspect of the present application, comprising the following steps: mixing cement, andesite, fly ash, manufactured sand and water.

[0012] The third aspect of the present application provides an application of the mortar for suppressing the alkali-activity of andesite aggregate described in the first aspect of the present application or the mortar obtained by the preparation method described in the second aspect of the present application in the field of hydropower and water conservancy projects.

[0013] The beneficial effects of the present application include: the mortar for suppressing the alkali-activity of andesite aggregate described in the present application can effectively suppress the alkali-activity of andesite aggregate and solve the problem of insufficient supply of fly ash in hydropower projects in Tibetan areas. Specific Embodiments

[0014] The embodiments of the present invention are described in detail below. The examples of the embodiments are exemplary and are intended to explain the present invention, but should not be construed as limiting the present invention.

[0015] In the present invention, the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples", etc. mean that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. In addition, without contradiction, those skilled in the art can combine and combine the different embodiments or examples described in this specification and the features of different embodiments or examples.

[0016] The embodiments of the present application provide a mortar for suppressing the alkali-activity of andesite aggregate, comprising raw materials in the following weight percentages: 12.1%-17.5% of cement, 6.7% of andesite, 2.7%-8.1% of fly ash, 60.5% of manufactured sand, and the balance being water.

[0017] In some embodiments of the present application, the cement is Portland 42.5 cement or ordinary Portland 42.5 cement, and the fineness of the cement is 300-350 m 2 / kg, such as 300 m 2 / kg, 320 m 2 / kg, 330 m 2 / kg, 350 m 2 / kg, etc.

[0018] In some embodiments of the present application, the artificial sand is artificial sand ground from dacite aggregate, and the fineness of the artificial sand is 2.4 - 2.8 mesh, such as 2.4 mesh, 2.5 mesh, 2.6 mesh, 2.8 mesh, etc.

[0019] In some embodiments of the present application, the particle fineness of the dacite is such that the residue on a 45μm square-hole sieve is 10% - 20%, such as 10%, 12%, 15%, 18%, 20%, etc.

[0020] In some embodiments of the present application, the fly ash grade is Class F, Grade II, and the particle fineness of the fly ash is such that the residue on a 45μm square-hole sieve is 15% - 25%, such as 15%, 18%, 20%, 22%, 25%, etc.

[0021] In some embodiments of the present application, the alkali activity of the mortar is such that the expansion rate of the 28d mortar specimen is less than 0.10%.

[0022] The embodiments of the present application also provide a method for preparing the mortar for inhibiting the alkali activity of dacite aggregate described in the first aspect of the present application, including the following steps: mixing cement, dacite, fly ash, artificial sand and water.

[0023] The embodiments of the present application also provide an application of the mortar for inhibiting the alkali activity of dacite aggregate described in the first aspect of the present application or the mortar obtained by the preparation method described in the second aspect of the present application in hydropower and water conservancy projects.

[0024] The technical solution of the present application will be further described below in conjunction with specific embodiments.

[0025] Example 1

[0026] A mortar for inhibiting the alkali activity of dacite aggregate, including Portland 42.5 cement with a particle fineness of 300m 2 / kg, 260g, 100g of dacite fine powder with a residue of 15% on a 45μm square-hole sieve, 40g of fly ash with a residue of 19% on a 45μm square-hole sieve, 900g of dacite artificial sand with a fineness of 2.5 mesh, and 188g of water.

[0027] The method for preparing the mortar for inhibiting the alkali activity of dacite aggregate described in Example 1 includes the following steps: mixing cement, dacite fine powder, fly ash, dacite artificial sand and water and stirring evenly.

[0028] The mortar for inhibiting the alkali activity of dacite aggregate includes 17.5% cement, 6.7% dacite fine powder, 2.7% fly ash, 60.5% sand, and 12.6% water.

[0029] Example 2

[0030] A mortar for inhibiting the alkali-activity of dacite aggregate, comprising 240 g of Portland 42.5 cement with a particle fineness of 300 m 2 / kg, 100 g of dacite micro-powder with a residue on a 45-μm square-hole sieve of 15%, 60 g of fly ash with a residue on a 45-μm square-hole sieve of 19%, 900 g of dacite artificial sand with a particle fineness of 2.5 mesh, and 188 g of water.

[0031] The preparation method of the mortar for inhibiting the alkali-activity of dacite aggregate described in Example 2 comprises the following steps: mixing the cement, dacite micro-powder, fly ash, dacite artificial sand, and water evenly.

[0032] The mortar for inhibiting the alkali-activity of dacite aggregate comprises 16.1% of cement, 6.7% of dacite micro-powder, 4.0% of fly ash, 60.5% of sand, and 12.6% of water.

[0033] Example 3

[0034] A mortar for inhibiting the alkali-activity of dacite aggregate, comprising 220 g of Portland 42.5 cement with a particle fineness of 300 m 2 / kg, 100 g of dacite micro-powder with a residue on a 45-μm square-hole sieve of 15%, 80 g of fly ash with a residue on a 45-μm square-hole sieve of 19%, 900 g of dacite artificial sand with a particle fineness of 2.5 mesh, and 188 g of water.

[0035] The preparation method of the mortar for inhibiting the alkali-activity of dacite aggregate described in Example 3 comprises the following steps: mixing the cement, dacite micro-powder, fly ash, dacite artificial sand, and water evenly.

[0036] The mortar for inhibiting the alkali-activity of dacite aggregate comprises 14.8% of cement, 6.7% of dacite micro-powder, 5.4% of fly ash, 60.5% of sand, and 12.6% of water.

[0037] Example 4

[0038] A mortar for inhibiting the alkali-activity of dacite aggregate, comprising 200 g of Portland 42.5 cement with a particle fineness of 300 m 2 / kg, 100 g of dacite micro-powder with a residue on a 45-μm square-hole sieve of 15%, 100 g of fly ash with a residue on a 45-μm square-hole sieve of 19%, 900 g of dacite artificial sand with a particle fineness of 2.5 mesh, and 188 g of water.

[0039] The preparation method of the mortar for inhibiting the alkali-activity of dacite aggregate described in Example 4 comprises the following steps: mixing the cement, dacite micro-powder, fly ash, dacite artificial sand, and water evenly.

[0040] The mortar for inhibiting the alkali activity of dacite aggregate comprises 13.4% cement, 6.7% dacite fine powder, 6.7% fly ash, 60.5% sand and 12.6% water.

[0041] Example 5

[0042] A mortar for inhibiting the alkali activity of dacite aggregate, comprising a mortar having a particle size of 300m 2 / kg silicate 42.5 cement 180g, dacite micro powder with a particle fineness of 15% on a 45μm square hole sieve, 120g fly ash with a particle fineness of 19% on a 45μm square hole sieve, 900g dacite artificial sand with a particle fineness of 2.5 mesh, and 188g water.

[0043] The method for preparing the mortar for inhibiting the alkali activity of dacite aggregate described in Example 5 comprises the following steps: mixing cement, dacite fine powder, fly ash, dacite artificial sand and water and stirring them uniformly.

[0044] The mortar for inhibiting the alkali activity of dacite aggregate comprises 12.1% cement, 6.7% dacite fine powder, 8.1% fly ash, 60.5% sand and 12.6% water.

[0045] Comparative Example 1

[0046] A mortar for inhibiting the alkali activity of dacite aggregate, comprising a mortar having a particle size of 300m 2 300g of silicate 42.5 cement / kg, 100g of dacite micro powder with a particle fineness of 15% on a 45μm square hole sieve, 900g of dacite artificial sand with a particle fineness of 2.5 mesh, and 188g of water.

[0047] The preparation method of the mortar for inhibiting the alkali activity of dacite aggregate described in Comparative Example 1 comprises the following steps: mixing cement, dacite fine powder, dacite artificial sand and water and stirring them uniformly.

[0048] The mortar for inhibiting the alkali activity of dacite aggregate comprises 20.2% cement, 6.7% dacite fine powder, 60.5% sand and 12.6% water.

[0049] Comparative Example 2

[0050] A mortar for inhibiting the alkali activity of dacite aggregate, comprising a mortar having a particle size of 300m 2 240 g of silicate 42.5 cement (1000 g / kg), 160 g of dacite fine powder with a particle size of 15% on a 45 μm square sieve, 900 g of dacite artificial sand with a particle size of 2.5 mesh, and 188 g of water.

[0051] The preparation method of the mortar for inhibiting the alkali activity of andesite aggregate described in Comparative Example 2 includes the following steps: uniformly mixing cement, andesite fine powder, andesite manufactured sand and water.

[0052] The mortar for inhibiting the alkali activity of andesite aggregate includes 16.1% of cement, 10.8% of andesite fine powder, 60.5% of sand, and 12.6% of water.

[0053] Comparative Example 3

[0054] A mortar for inhibiting the alkali activity of andesite aggregate includes 200 g of Portland 42.5 cement with a particle fineness of 300 m 2 / kg, 200 g of andesite fine powder with a residue on a 45-μm square-hole sieve of 15% for particle fineness, 900 g of andesite manufactured sand with a particle fineness of 2.5 mesh, and 188 g of water.

[0055] The preparation method of the mortar for inhibiting the alkali activity of andesite aggregate described in Comparative Example 3 includes the following steps: uniformly mixing cement, andesite fine powder, andesite manufactured sand and water.

[0056] The mortar for inhibiting the alkali activity of andesite aggregate includes 13.4% of cement, 13.4% of andesite fine powder, 60.5% of sand, and 12.6% of water.

[0057] Study on the alkali activity performance of the mortar for inhibiting the alkali activity of andesite aggregate described in Examples 1-5 and Comparative Examples 1-3 of the present application.

[0058] Using the mortar bar rapid method to test the expansion rate of the mortar for inhibiting the alkali activity of andesite aggregate described in Examples 1-5 and Comparative Examples 1-3 of the present application, and the test results are shown in Table 1.

[0059] Table 1

[0060]

[0061] It can be seen from Table 1 that: after adding andesite and fly ash to the mortar in Examples 1-5 of the present application, the expansion rate of the 28-day mortar specimens is less than 0.10%. According to the provisions of the "Test Code for Aggregates of Hydraulic Concrete" DL / T 5151-2014, the evaluation of the inhibitory effect of the compound admixture of andesite fine powder and fly ash on the alkali-aggregate reaction hazard of andesite aggregate is effective. With the increase of the dosage of andesite fine powder and fly ash, the inhibitory effect is better.

[0062] When andesite is added alone, the expansion rate of the mortar specimens on the third day is higher than that of the reference aggregate, and the expansion rate on the 28th day is less than that of the reference aggregate, but still greater than 0.10%. It shows that andesite fine powder promotes the alkali activity of the aggregate in the early stage and starts to play a certain inhibitory effect later, but adding andesite fine powder alone cannot effectively inhibit the alkali activity of the aggregate.

[0063] Although the above embodiments have been shown and described, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Any changes, modifications, substitutions, and variations made by those of ordinary skill in the art to the above embodiments are within the scope of protection of the present invention.

Claims

1. A mortar for suppressing the alkali activity of andesite aggregate, characterized in that, The raw materials include the following components by weight percentage: 12.1% - 17.5% of cement, 6.7% of dacite, 2.7% - 8.1% of fly ash, 60.5% of manufactured sand, and the balance is water.

2. The mortar for inhibiting the alkali activity of andesite aggregate according to claim 1, characterized in that, The cement is Portland 42.5 cement or ordinary Portland 42.5 cement, and the fineness of the cement is 300-350m 2 / kg.

3. The mortar for suppressing the alkali activity of andesite aggregate according to claim 1, characterized in that The manufactured sand is the manufactured sand ground from dacite aggregate, and the fineness of the manufactured sand is 2.4 - 2.8 mesh.

4. The mortar for suppressing the alkali activity of andesite aggregate according to claim 1, wherein The particle fineness of the dacite is that the residue on a 45μm square hole sieve is 10% - 20%.

5. The mortar for suppressing the alkali activity of aggregates according to claim 1, characterized in that The fly ash grade is Class F Grade II, and the particle fineness of the fly ash is that the residue on a 45μm square hole sieve is 15% - 25%.

6. The mortar for suppressing the alkali activity of andesite aggregate according to claim 1, characterized in that, The alkali activity of the mortar is that the expansion rate of the 28d mortar specimen is less than 0.10%.

7. The preparation method of the mortar for inhibiting the alkali activity of rhyolite aggregate according to any one of claims 1-6, characterized in that, It includes the following steps: just mix cement, dacite, fly ash, manufactured sand and water.

8. Application of the mortar for inhibiting the alkali activity of dacite aggregate according to any one of claims 1 - 6 or the mortar obtained by the preparation method according to claim 7 in the aspect of hydropower and water conservancy projects.

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