Anti-abrasion tuff mortar as well as preparation method and application thereof

Abstract

The invention discloses abrasion-resistant tuff mortar as well as a preparation method and application thereof, and belongs to the technical field of hydraulic construction materials. The abrasion-resistant tuff mortar provided by the invention has high compressive strength, high breaking strength and good abrasion resistance, and can solve the problem that the durability of concrete in hydraulic runners and wading piers in the Qinghai-Tibet Plateau region is reduced. Meanwhile, after 72 hours of underwater steel ball abrasion, the mass loss of the test piece is similar to that of the traditional high-strength mortar, and the CO2 emission and energy consumption of the high-strength mortar are reduced by 10.7%-32.2% and 9.5%-28.6% compared with those of the traditional high-strength mortar. Therefore, the abrasion-resistant tuff mortar disclosed by the invention can greatly reduce the CO2 emission and energy consumption of a gelling system in the Qinghai-Tibet Plateau region, and can improve the abrasion resistance of a hydraulic structure and prolong the service life of the hydraulic structure in a plateau wading environment when being used for the hydraulic structure in the wading region of the Qinghai-Tibet Plateau.

Description

Technical Field

[0001] The invention belongs to the technical field of hydraulic construction materials, and particularly relates to an abrasion-resistant tuff mortar and a preparation method and application thereof. Background Art

[0002] Hydraulic concrete flood discharge structures in the Qinghai-Tibet Plateau are often damaged by abrasion due to high-velocity water flows, leading to a gradual loss of concrete quality and a breakdown of their bearing capacity. Hydraulic concrete is constantly exposed to the abrasive effects of sediment-laden water flows, and improving its abrasion resistance is a core requirement for ensuring the long-term durability of engineering structures. High-strength cement-based composites, due to their dense microstructure and high strength, can significantly slow material erosion caused by abrasion caused by sediment-laden water flows, thereby extending the life of the structure. However, their high strength still relies heavily on high cement content, which has led to a surge in carbon emissions, excessive resource consumption, and rising costs.

[0003] To address the environmental impacts of traditional cement production, alternative cementitious materials such as granulated blast furnace slag, fly ash, and silica fume are increasingly being used to partially replace cement. However, the supply of these industrial byproducts is gradually decreasing. Tuff, abundant in the Qinghai-Tibet Plateau, could be used as an auxiliary cementitious material to significantly reduce the amount of cement used in abrasion-resistant materials, thereby reducing carbon emissions and energy consumption in their production. Tuff powder, a natural volcanic ash material, is widely considered a potential alternative to auxiliary cementitious materials due to its microaggregate, nucleation, and volcanic ash effects, offering a new approach to resolving this dilemma. However, precise control of the tuff powder dosage is crucial to its effectiveness. The mechanisms and mechanisms governing the influence of tuff powder dosage on the mechanical properties and abrasion-resistant behavior of composite cementitious systems remain unclear, resulting in a lack of data support for the design and selection of tuff powder dosage in engineering practice. Summary of the Invention

[0004] In view of the above-mentioned prior art, the present invention provides an abrasion-resistant tuff mortar and a preparation method and application thereof, so as to solve the technical problems of carbon emissions and high energy consumption of existing abrasion-resistant materials.

[0005] In order to achieve the above-mentioned purpose, the technical solution adopted by the present invention is to provide an impact-resistant tuff mortar, comprising the following components in parts by mass: 72 to 117 parts of cement, 15 to 60 parts of tuff powder, 18 parts of silica fume, 54 parts of fine sand, 31.5 parts of water, 2.2 parts of water reducer, and 0.9 part of defoaming agent.

[0006] On the basis of the above technical solution, the present invention can also be improved as follows.

[0007] Furthermore, the abrasion-resistant tuff mortar includes the following components in parts by mass: 102 parts of cement, 30 parts of tuff powder, 18 parts of silica fume, 54 parts of fine sand, 31.5 parts of water, 2.2 parts of water reducer, and 0.9 part of defoamer.

[0008] Furthermore, the cement is silicate cement with a strength grade of 42.5R or 52.5R.

[0009] Furthermore, the silicon dioxide content in the silica fume is not less than 96%.

[0010] Furthermore, the particle size of the tuff powder ranges from 0.15 to 0.65 mm; the fine sand is machine-made sand, and its particle size ranges from 0.1 to 0.6 mm.

[0011] Furthermore, the water reducer is a polycarboxylic acid type water reducer.

[0012] Furthermore, the defoaming agent is a polyether defoaming agent.

[0013] The present invention also discloses a method for preparing the above-mentioned abrasion-resistant tuff mortar, which comprises the following steps: S1: Cement, tuff powder, silica fume, machine-made sand and defoamer are mixed and stirred uniformly to obtain a mixture; S2: Add the water reducer into water and stir evenly to obtain a water reducer solution; S3: mixing the water-reducing agent solution with the mixed material and stirring evenly to obtain a slurry; S4: Fill the slurry into a mold, demould after 45-50 hours, and then cure it at a temperature of 18-22°C and a humidity of >95% for 25-30 days.

[0014] Furthermore, the stirring speed in S1 and S2 is 300-350 rpm, and the stirring time is 3-5 min; the stirring speed in S3 is 540-600 rpm, and the stirring time is 5-6 min.

[0015] The invention also discloses the application of the abrasion-resistant tuff mortar in hydraulic flow channel engineering in the Qinghai-Tibet Plateau area.

[0016] The beneficial effects of the present invention are: 1. The low-carbon, high-strength, impact-resistant tuff mortar prepared by the present invention has a compressive strength of 101.2-109.6 MPa at 28 days, a flexural strength of 21.89-22.89 MPa, and an impact-resistant strength of 150.5-160.47 h·m 2 kg -1 That is, the water-related anti-cavitation engineering cement-based composite material in this application has excellent mechanical properties and can solve the problem of reduced durability of concrete paths in hydraulic channels and water-related bridge piers in the Qinghai-Tibet Plateau.

[0017] 2. The tuff-infused abrasion-resistant material prepared by this invention requires no calcination and only needs to be ball-milled to a certain particle size before replacing a large amount of cement. This reduces CO2 emissions and energy consumption. Compared with traditional high-strength mortar, CO2 emissions and energy consumption are reduced by 10.7% to 32.2% and 9.5% to 28.6% respectively. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 28-day compressive strength (a) and flexural strength (b) comparison chart of the products obtained in Comparative Example 1 and Examples 1 to 4; Figure 2 This is the abraded surface morphology of the products obtained in Comparative Example 1 and Examples 1 to 4; Figure 3 This is a comparison chart of the abrasion resistance of the products obtained in Comparative Example 1 and Examples 1 to 4; Figure 4 This is a comparison chart of CO2 emissions during the preparation process of Comparative Example 1 and Examples 1 to 4; Figure 5 This is a comparison chart of energy consumption of the products prepared in Comparative Example 1 and Examples 1 to 4. DETAILED DESCRIPTION

[0019] The specific implementation methods of the present invention are described in detail below with reference to the embodiments.

[0020] Example 1 An abrasion-resistant tuff mortar (AAM), the components and mass fractions of the components of the abrasion-resistant tuff mortar are shown in the following table: Among them, the cement is ordinary Portland cement with strength grade 52.5R; the silicon dioxide content in the silica fume is not less than 96%; the particle size of the tuff powder is 0.15~0.65mm; the particle size of the machine-made sand is 0.1~0.6 mm; the water reducer is a polycarboxylic acid type water reducer (DC-1059, water reduction rate 40%); the defoamer is a polyether type defoamer (Rilian DC-5700); and the water is tap water.

[0021] The abrasion-resistant tuff mortar in this embodiment is prepared by the following steps: S1: Add cement, tuff powder, silica fume, machine-made sand and defoamer into a mixing bucket and dry mix at 300 rpm for 5 minutes to obtain a mixture; S2: Mix the water reducer with water and stir at 300 rpm for 5 min to obtain a water reducer solution; S3: Mix the water-reducing agent solution with the mixture and stir at a speed of 540 rpm for 5 min to obtain a slurry; S4: Fill the slurry into a mold, demould after 48 hours, and then cure it at a temperature of 20°C and a humidity of >95% for 28 days.

[0022] Example 2 An abrasion-resistant tuff mortar (AAM), the components and mass fractions of the components of the abrasion-resistant tuff mortar are shown in the following table: Among them, the cement is ordinary Portland cement with strength grade 52.5R; the silicon dioxide content in the silica fume is not less than 96%; the particle size of the tuff powder is 0.15~0.65mm; the particle size of the machine-made sand is 0.1~0.6 mm; the water reducer is a polycarboxylic acid type water reducer (DC-1059, water reduction rate 40%); the defoamer is a polyether type defoamer (Rilian DC-5700); and the water is tap water.

[0023] The abrasion-resistant tuff mortar in this embodiment is prepared by the following steps: S1: Add cement, tuff powder, silica fume, machine-made sand and defoamer into a mixing bucket and dry mix at 350 rpm for 3 minutes to obtain a mixture; S2: Mix the water reducer with water and stir at 350 rpm for 3 min to obtain a water reducer solution; S3: Mix the water-reducing agent solution with the mixture and stir at a speed of 580 rpm for 6 min to obtain a slurry; S4: Fill the slurry into a mold, demould after 48 hours, and then cure it at a temperature of 20°C and a humidity of >95% for 28 days.

[0024] Example 3 An abrasion-resistant tuff mortar (AAM), the components and mass fractions of the components of the abrasion-resistant tuff mortar are shown in the following table: Among them, the cement is ordinary Portland cement with strength grade 52.5R; the silicon dioxide content in the silica fume is not less than 96%; the particle size of the tuff powder is 0.15~0.65mm; the particle size of the machine-made sand is 0.1~0.6 mm; the water reducer is a polycarboxylic acid type water reducer (DC-1059, water reduction rate 40%); the defoamer is a polyether type defoamer (Rilian DC-5700); and the water is tap water.

[0025] The abrasion-resistant tuff mortar in this embodiment is prepared by the following steps: S1: Add cement, tuff powder, silica fume, machine-made sand and defoamer into a mixing bucket and dry mix at 300 rpm for 5 minutes to obtain a mixture; S2: Mix the water reducer with water and stir at 300 rpm for 5 min to obtain a water reducer solution; S3: Mix the water-reducing agent solution with the mixture and stir at a speed of 540 rpm for 5 min to obtain a slurry; S4: Fill the slurry into a mold, demould after 48 hours, and then cure it at a temperature of 20°C and a humidity of >95% for 28 days.

[0026] Example 4 An abrasion-resistant tuff mortar (AAM), the components and mass fractions of the components of the abrasion-resistant tuff mortar are shown in the following table: Among them, the cement is ordinary Portland cement with strength grade 52.5R; the silicon dioxide content in the silica fume is not less than 96%; the particle size of the tuff powder is 0.15~0.65mm; the particle size of the machine-made sand is 0.1~0.6 mm; the water reducer is a polycarboxylic acid type water reducer (DC-1059, water reduction rate 40%); the defoamer is a polyether type defoamer (Rilian DC-5700); and the water is tap water.

[0027] The abrasion-resistant tuff mortar in this embodiment is prepared by the following steps: S1: Add cement, tuff powder, silica fume, machine-made sand and defoamer into a mixing bucket and dry mix at 300 rpm for 5 minutes to obtain a mixture; S2: Mix the water reducer with water and stir at 300 rpm for 5 min to obtain a water reducer solution; S3: Mix the water-reducing agent solution with the mixture and stir at a speed of 540 rpm for 5 min to obtain a slurry; S4: Fill the slurry into a mold, demould after 48 hours, and then cure it at a temperature of 20°C and a humidity of >95% for 28 days.

[0028] Comparative Example 1 The components and mass fractions of traditional high-strength mortar are shown in the following table: Among them, the cement is ordinary Portland cement with strength grade 52.5R; the silicon dioxide content in the silica fume is not less than 96%; the particle size of the machine-made sand is 0.1~0.6 mm; the water reducer is a polycarboxylic acid type water reducer (DC-1059, water reduction rate 40%); the defoamer is a polyether type defoamer (Rilian DC-5700); and the water is tap water.

[0029] The mortar in this comparative example was prepared by the following steps: S1: Add cement, silica fume, machine-made sand and defoamer into a mixing bucket and dry mix at 300 rpm for 5 min to obtain a mixture; S2: Mix the water reducer with water and stir at 300 rpm for 5 min to obtain a water reducer solution; S3: Mix the water-reducing agent solution with the mixture and stir at a speed of 540 rpm for 5 min to obtain a slurry; S4: Fill the slurry into a mold, demould after 48 hours, and then cure it at a temperature of 20°C and a humidity of >95% for 28 days.

[0030] Experimental example The relevant properties of the products obtained in Examples 1 to 4 and Comparative Example 1 were tested, and the results are as follows Figures 1 to 5 And as shown in Table 1. Among them, Figure 1 The 28-day compressive strength (a) and flexural strength (b) of the products obtained in Comparative Example 1 and Examples 1 to 4 are compared; Figure 2 This is the abraded surface morphology of the products obtained in Comparative Example 1 and Examples 1 to 4; Figure 3 This is a comparison chart of the abrasion resistance of the products obtained in Comparative Example 1 and Examples 1 to 4; Figure 4 This is a comparison chart of CO2 emissions during the preparation process of Comparative Example 1 and Examples 1 to 4; Figure 5 This is a comparison chart of energy consumption of the products prepared in Comparative Example 1 and Examples 1 to 4.

[0031] Table 1 Test results of relevant performance tests of products in Examples 1 to 4 and Comparative Example 1 from Figures 1 to 5 As can be seen from Table 1, with the increase of tuff content, the compressive strength of the products in the four groups of examples shows a slightly decreasing trend. The compressive strength of Example 1, Example 2, Example 3 and Example 4 is reduced by 0.7%, 5.1%, 8.3% and 12.5% ​​compared with Comparative Example 1. Overall, after 10% to 30% of tuff is replaced, the compressive strength of the matrix will not be significantly reduced. The main reason is that the volcanic ash activity of the tuff is promoted under steam curing conditions, which increases the amount of hydrated calcium silicate gel produced inside the matrix. The flexural strength of the four groups of examples after 28 days all exceeded 21 MPa, and the flexural strength did not decrease after tuff replaced cement.

[0032] From the comparison of Examples 1 to 4 with Comparative Example 1, it can be seen that, in terms of abrasion resistance, as the amount of tuff increases, the abrasion resistance of the mortar first decreases and then increases, and then continues to decrease. When the amount is 10% to 30%, the abrasion resistance does not decrease significantly. In addition, compared with Comparative Example 1, the CO2 emissions and energy consumption of Example 2 are reduced by 21.4% and 17.1%, respectively. This shows that when tuff replaces 10% to 20% of cement, the impact on the mechanical properties of the matrix is ​​relatively low, and at the same time, the CO2 emissions and energy consumption of the mortar can be greatly reduced, which lays the foundation for the engineering application of the new auxiliary cementitious material - tuff. Therefore, the tuff of the present invention has good volcanic ash activity. At the same time, by adding tuff, a mortar with high abrasion resistance can be prepared, which can greatly improve the durability of hydraulic channels or wading concrete in the Qinghai-Tibet Plateau and extend its service life.

[0033] Although the specific embodiments of the present invention have been described in detail in conjunction with the embodiments, this should not be construed as limiting the scope of protection of this patent. Within the scope described by the claims, various modifications and variations that can be made by those skilled in the art without creative work still fall within the scope of protection of this patent.

Claims

1. A wear-resistant tuff mortar, characterized in that: The invention comprises the following components in parts by mass: 72 to 117 parts of cement, 15 to 60 parts of tuff powder, 18 parts of silica fume, 54 parts of fine sand, 31.5 parts of water, 2.2 parts of water reducing agent and 0.9 part of defoaming agent.

2. The method according to claim 1, wherein: The invention comprises the following components in parts by mass: 102 parts of cement, 30 parts of tuff powder, 18 parts of silica fume, 54 parts of fine sand, 31.5 parts of water, 2.2 parts of water reducing agent and 0.9 part of defoaming agent.

3. The abrasion-resistant tuff mortar according to claim 1 or 2, characterized in that: The cement is silicate cement with a strength grade of 42.5R or 52.5R.

4. The abrasion-resistant tuff mortar according to claim 1 or 2, characterized in that: The silicon dioxide content in the silica ash is not less than 96%.

5. The abrasion-resistant tuff mortar according to claim 1 or 2, characterized in that: The particle size of the tuff powder is in the range of 0.15 to 0.65 mm; the fine sand is machine-made sand, and the particle size is in the range of 0.1 to 0.6 mm.

6. The abrasion-resistant tuff mortar according to claim 1 or 2, characterized in that: The water reducer is a polycarboxylic acid type water reducer.

7. The abrasion-resistant tuff mortar according to claim 1 or 2, characterized in that: The defoamer is a polyether defoamer.

8. The method for preparing the abrasion-resistant tuff mortar according to any one of claims 1 to 7, characterized in that: The following steps are involved: S1: Cement, tuff powder, silica fume, machine-made sand and defoamer are mixed and stirred uniformly to obtain a mixture; S2: Add the water reducer into water and stir evenly to obtain a water reducer solution; S3: mixing the water-reducing agent solution with the mixed material and stirring evenly to obtain a slurry; S4: Fill the slurry into a mold, demould after 45-50 hours, and then cure it at a temperature of 18-22°C and a humidity of >95% for 25-30 days.

9. The preparation method according to claim 8, characterized in that: The stirring speed in S1 and S2 is 300~350 rpm, and the stirring time is 3~5 min; the stirring speed in S3 is 540~600 rpm, and the stirring time is 5~6 min.

10. Use of the abrasion-resistant tuff mortar according to any one of claims 1 to 7 in hydraulic channel projects in the Qinghai-Tibet Plateau.

Images