An aggregate sulphate erosion inhibition method based on gradation regulation and coordination with ion solidification

Abstract

This invention belongs to the field of concrete technology and provides a method for inhibiting aggregate sulfate attack based on gradation control, cementitious material optimization, and ion curing synergy. The method involves using the initial aggregate with an SO3 content ≥0.5% as fine aggregate, rather than coarse aggregate, in concrete or mortar. The fine aggregate is composed of the initial aggregate and compliant aggregates, with a fineness modulus of 2.4~2.8. The invention employs different treatment methods for different SO3 contents in the initial aggregate: when the SO3 content is low, the aggregate is compounded according to a specific gradation curve; when the SO3 content is high, the aggregate is pretreated. The cement used in the cementitious material is low-C3A or low-C3S silicate cement, and the admixtures are single or double admixtures of F-type fly ash and silica fume to improve the matrix's corrosion resistance. A sulfate curing agent is added to fix sulfate ions and reduce attack.

Description

Technical Field

[0001] This invention relates to the field of concrete technology, and in particular to a method for inhibiting aggregate sulfate erosion based on gradation control, cementitious material optimization, and synergistic ion curing. Background Technology

[0002] Sulfate corrosion resistance is a crucial aspect of concrete durability research, and it is also one of the most complex and damaging forms of environmental corrosion. Soils and water in coastal areas contain high levels of sulfates, which can significantly degrade the performance of concrete structures in these regions. Sulfate corrosion of concrete involves two aspects: firstly, sulfate ions from the environment penetrate the concrete and react with hydration products, causing expansion, cracking, and spalling; secondly, the high content of soluble sulfates in the concrete raw materials leads to the leaching of soluble sulfates during long-term service, reducing the concrete's strength and affecting its durability.

[0003] Currently, research on sulfate resistance mainly focuses on resisting the penetration of sulfate ions in the environment. This is achieved by studying admixture formulations and sulfate-resistant agents to improve the concrete's resistance to environmental sulfates. For example, CN115974447A discloses an admixture for red mud-based high-sulfur-resistant cementitious materials, its preparation method, and its application. The admixture includes a sulfate-resistant agent, fly ash, silica fume, and SAP. The sulfate-resistant agent is made from red mud, calcium-based raw materials, and iron-based raw materials. CN110922125A discloses sulfate-resistant concrete, which resists sulfate ion erosion by adding steel fibers, epoxy resin, barium hydroxide, and sodium citrate to delay the formation of ettringite crystals and gypsum. To address the sulfate attack in concrete raw materials, especially sulfates in aggregates, CN115010438A discloses a method for preparing recycled fine aggregate concrete with improved sulfate resistance. The method involves first soaking the recycled fine aggregate in a sodium acetate solution, then accelerating carbonation, and finally mixing it with cement, admixtures, and additives. The pretreatment of the recycled fine aggregate aims to increase its utilization rate. A composite additive is prepared using sodium methylene dimethylnaphthalene sulfonate and nano-quartz sand powder, and an organosilicon waterproofing agent is incorporated to enhance sulfate resistance. Essentially, this method improves the gelling material rather than addressing sulfate attack from the aggregate itself. Generally, according to GB / T 14684-2022 "Construction Sand," the sulfate and sulfide content (based on SO3 mass) in construction sand should not exceed 0.5%. Related studies indicate that using aggregates with an SO3 content of no more than 0.5% has a relatively limited impact on the durability of concrete. However, in practical engineering applications, due to the lack of sophisticated treatment methods for aggregates with excessive SO3 content, aggregates are often directly discarded. This practice not only exacerbates the difficulty of material selection and construction costs but also results in a significant waste of resources.

[0004] Therefore, this invention aims to solve the technical problems of low utilization rate and serious resource waste of aggregates with excessive SO3 content, and provides a method for inhibiting sulfate erosion of aggregates based on gradation control, cementitious material optimization and ion solidification synergy. Summary of the Invention

[0005] The purpose of this invention is to provide a method for inhibiting sulfate erosion of aggregates based on gradation control, cementitious material optimization, and synergistic ion curing, addressing the shortcomings of existing technologies.

[0006] To achieve the above-mentioned objectives, the present invention provides the following technical solution: This invention provides a method for inhibiting sulfate attack on aggregates based on gradation control, cementitious material optimization, and ion curing synergy. When the SO3 mass content in the initial aggregate is ≥0.5%, the initial aggregate is not used as coarse aggregate, but only as fine aggregate, and is applied to concrete or mortar. The fine aggregate is composed of initial aggregate and compliant aggregate, and the fineness modulus of the fine aggregate is 2.4~2.8.

[0007] Preferably, when the SO3 mass content in the initial aggregate is 0.5~1.5%, the particle size distribution of the initial aggregate is controlled as follows: 5~2.5mm 30~35%, 2.5~1.25mm 25~30%, 1.25~0.63mm 25~30%, 0.63~0.32mm 7~12%, 0.32~0.16mm 5~8%, <0.16mm 0~3%, and the fineness modulus of the initial aggregate is 3.61~3.84.

[0008] Preferably, when the SO3 mass content in the initial aggregate is 1.5~2.5%, the process further includes pre-treating the initial aggregate to obtain pre-treated aggregate, controlling the particle size distribution of the pre-treated aggregate as follows: 5~2.5mm 30~35%, 2.5~1.25mm 25~30%, 1.25~0.63mm 25~30%, 0.63~0.32mm 7~12%, 0.32~0.16mm 5~8%, <0.16mm 0~3%, and the fineness modulus of the pre-treated aggregate is 3.61~3.84; The fine aggregate is composed of pretreated aggregate and compliant aggregate, and the fineness modulus of the fine aggregate is 2.4~2.8.

[0009] Preferably, the pretreatment includes high-temperature steam oxidation or microwave heat treatment, and the SO3 mass content in the pretreated aggregate is 0.5~1.5%.

[0010] Preferably, the SO3 content in the compliant aggregate is <0.5%, and the mass fraction of the compliant aggregate in the fine aggregate does not exceed 40%.

[0011] Preferably, the cementitious material in the concrete or mortar includes cement and admixtures; The cement contains ≤2% by mass of tricalcium aluminate (C3A) and ≤35% by mass of tricalcium silicate (C3S).

[0012] Preferably, the admixture comprises type F fly ash and / or silica fume.

[0013] Preferably, when the admixture is Class F fly ash, the dosage is 20-30%; When the admixture is silicon powder, the dosage is 3-8%; When the admixture is type F fly ash and silica fume, the amount of type F fly ash is 20-25% and the amount of silica fume is 3-5%.

[0014] Preferably, the concrete or mortar also contains a sulfate curing agent, wherein the sulfate curing agent is a barium salt, and the amount of sulfate curing agent is 3 to 5% of the cementitious material.

[0015] The beneficial effects of this invention are: 1) This invention treats initial aggregates with excessive SO3 content by setting corresponding treatment methods according to the specific SO3 content. For initial aggregates with SO3 content of 0.5~1.5%, the particle size distribution is controlled and it is compounded with compliant aggregates as fine aggregates to form a specific gradation curve. For initial aggregates with SO3 content of 1.5~2.5%, pretreatment is performed to reduce the SO3 content to below 1.5%, and then the particle size distribution is controlled and it is compounded with compliant aggregates as fine aggregates. At the same time, the fineness modulus of the fine aggregates is strictly controlled, which effectively inhibits sulfate attack caused by excessive SO3 content in the aggregates.

[0016] 2) This invention uses silicate cement with low C3A and low C3S content, and incorporates F-type fly ash and / or silica fume as admixtures. The amount of admixtures is reasonably controlled to improve the ability to resist sulfate attack from the perspective of gel materials and enhance the matrix's resistance to attack. Barium salt is added as a sulfate curing agent, which reacts with sulfate to generate barium sulfate precipitate, thereby fixing sulfate ions.

[0017] 3) This invention adopts a technical approach that combines gradation control, cementitious material optimization and ion curing, which not only ensures the long-term durability of concrete / mortar, but also effectively improves the comprehensive utilization rate of sulfur-containing aggregates, thus achieving significant economic and social benefits. Detailed Implementation

[0018] This invention provides a method for inhibiting sulfate attack on aggregates based on gradation control, cementitious material optimization, and ion curing synergy. When the SO3 mass content in the initial aggregate is ≥0.5%, the initial aggregate is not used as coarse aggregate, but only as fine aggregate, and is applied to concrete or mortar. The fine aggregate is composed of initial aggregate and compliant aggregate, and the fineness modulus of the fine aggregate is 2.4~2.8.

[0019] In this invention, the fineness modulus of the fine aggregate is preferably 2.5 to 2.7, and more preferably 2.6.

[0020] Variations in aggregate particle size have a dual impact on its sulfate attack behavior: On the one hand, as particle size decreases, the specific surface area of ​​the aggregate increases, increasing the probability of contact with aluminate components in the cement, thereby accelerating the attack process, enhancing the reaction intensity, and ultimately leading to greater volume expansion. Therefore, it is necessary to strictly control the initial aggregate particle size distribution and adjust its gradation curve. On the other hand, when the aggregate particle size exceeds a certain critical value, the spatial distribution of attack products becomes the dominant factor: the reaction concentrates on the aggregate surface, causing expansive products to accumulate in the interfacial transition zone, forming local stress concentration, which in turn induces macroscopic expansion. Based on the above mechanism, initial aggregates with SO3 mass content ≥0.5% should not be used as coarse aggregates but should be crushed and processed into fine aggregates.

[0021] In this invention, when the SO3 mass content in the initial aggregate is 0.5-1.5% (including 0.5% and 1.5%), the particle size distribution of the initial aggregate is preferably controlled as follows: 5-2.5mm 30-35%, more preferably 31-34%, more preferably 32-33%; 2.5-1.25mm 25-30%, more preferably 26-29%, more preferably 27-28%; 1.25-0.63mm 25-30%, more preferably 26-29%, more preferably 27-28%; 0.63-0.32mm 7-12%, more preferably 8-11%, more preferably 9-10%; 0.32-0.16mm 5-8%, more preferably 6-7%, more preferably 6.5%; <0.16mm The initial aggregate has a fineness modulus of 0-3%, more preferably 0.5-2.5%, and even more preferably 1-2%. The fineness modulus of the initial aggregate is preferably 3.61-3.84, more preferably 3.68-3.80, and even more preferably 3.71-3.76. Initial aggregate with excessive SO3 content, after processing according to the aforementioned particle size distribution, has a high fineness modulus and needs to be blended with compliant aggregate with SO3 content <0.5% to obtain fine aggregate with a fineness modulus of 2.4-2.8.

[0022] In this invention, when the SO3 mass content in the initial aggregate is 1.5~2.5% (excluding 1.5% and including 2.5%), it is preferable to further include pre-treating the initial aggregate to obtain pre-treated aggregate. Preferably, the particle size distribution of the pre-treated aggregate is controlled as follows: 5~2.5mm 30~35%, more preferably 31~34%, more preferably 32~33%; 2.5~1.25mm 25~30%, more preferably 26~29%, more preferably 27~28%; 1.25~0.63mm 25~30%, more preferably 26~29%, more preferably 27~28%; 0.63~0.32mm 7~12%, more preferably 8~11%, more preferably 9~10%; 0.32~0.16mm 5~8%, more preferably 6~7%, more preferably 6.5%; <0.16mm 0~3%, more preferably 0.5~2.5%, more preferably 1~2%; the fineness modulus of the pretreated aggregate is preferably 3.61~3.84, more preferably 3.68~3.8, more preferably 3.71~3.76; The fine aggregate is preferably composed of pretreated aggregate and compliant aggregate, and the fineness modulus of the fine aggregate is preferably 2.4 to 2.8, further 2.5 to 2.7, and more preferably 2.6.

[0023] In this invention, the pretreatment preferably includes high-temperature steam oxidation or microwave heat treatment, and the SO3 mass content in the pretreated aggregate is preferably 0.5-1.5%, more preferably 0.8-1.2%, and even more preferably 1%. The SO3 in the initial aggregate exists in the form of gypsum or iron sulfides. The purpose of pretreatment is to consume or fix the SO3, thereby reducing the SO3 content in the initial aggregate and ensuring the safety of the fine aggregate.

[0024] In this invention, the temperature of the high-temperature steam oxidation is preferably 180~200℃, more preferably 185~195℃, and even more preferably 190℃; the time of the high-temperature steam oxidation is preferably 2~4h, more preferably 2.5~3.5h, and even more preferably 3h; the pressure of the high-temperature steam oxidation is preferably 0.8~1.5MPa, and even more preferably 1~1.2MPa. After the high-temperature steam oxidation is completed, water quenching is preferably performed to obtain pretreated aggregate.

[0025] In this invention, the microwave heat treatment temperature is preferably 220~250℃, more preferably 230~240℃; the microwave heat treatment time is preferably 3~8min, more preferably 4~7min, and more preferably 5min.

[0026] In this invention, the initial aggregate is preferably pre-wetted before being subjected to microwave heat treatment; The pre-wetting is preferably to a moisture content of 5-8%, and more preferably 6-7%.

[0027] In this invention, the SO3 content in the compliant aggregate is preferably <0.5%, more preferably <0.4%, and even more preferably <0.3%; the mass fraction of the compliant aggregate in the fine aggregate is preferably no more than 40%, more preferably no more than 38%, and even more preferably no more than 35%.

[0028] In this invention, the SO3 content is preferably calculated as the total amount of sulfides and sulfates.

[0029] In this invention, the cementitious material in the concrete or mortar preferably includes cement and admixtures; The mass content of tricalcium aluminate (C3A) in the cement is preferably ≤2%, more preferably ≤1.8%, and even more preferably ≤1.6%; the mass content of tricalcium silicate (C3S) is preferably ≤35%, more preferably ≤33%, and even more preferably ≤32%.

[0030] In this invention, the cement is preferably low-heat silicate cement.

[0031] In this invention, the admixture preferably comprises type F fly ash and / or silicon powder.

[0032] In this invention, when the admixture is type F fly ash, the preferred dosage is 20-30%, more preferably 22-28%, and even more preferably 25%. When the admixture is silicon powder, the preferred dosage is 3-8%, more preferably 4-7%, and even more preferably 5-6%. When the admixture is type F fly ash and silica fume, the preferred amount of type F fly ash is 20-25%, more preferably 21-24%, and even more preferably 22-23%; the preferred amount of silica fume is 3-5%, more preferably 3.5-4.5%, and even more preferably 4%.

[0033] In this invention, the concrete or mortar preferably further contains a sulfate curing agent, the sulfate curing agent is preferably a barium salt, and the dosage of the sulfate curing agent is preferably 3 to 5% of the cementitious material, more preferably 3.5 to 4.5%, and more preferably 4%.

[0034] In this invention, the barium salt preferably comprises one or more of barium silicate, barium phosphate, barium metaphosphate, barium carbonate, and barium hydroxide.

[0035] The technical solutions provided by the present invention will be described in detail below with reference to the embodiments, but they should not be construed as limiting the scope of protection of the present invention.

[0036] The cement used in the embodiments and comparative examples of the present invention is P·LH 42.5 low-heat silicate cement, and the initial aggregate is artificial sand.

[0037] The fine aggregates in the examples and comparative examples were processed from the original rock, and the details of the fine aggregates are shown in Table 1.

[0038] Table 1. Fine aggregate details

[0039] Example 1

[0040] Low-heat silicate cement, with a C3A content of 1.56% and a C3S content of 31.61%; The No. 3 fine aggregate is a mixture of initial aggregate and compliant aggregate, with the compliant aggregate comprising 40% by mass. The initial aggregate is processed from the No. 1 original rock, and the compliant aggregate is processed from the No. 2 original rock. The particle size distribution of the initial aggregate and the No. 3 fine aggregate is shown in Table 2.

[0041] Table 2. Particle size distribution of initial aggregate and No. 3 fine aggregate

[0042] Cement, No. 3 fine aggregate, and water are mixed in a mass ratio of 1:2.5:0.5 to obtain mortar.

[0043] Example 2

[0044] In Example 1, 25% of type F fly ash was added to the mortar.

[0045] Example 3

[0046] 5% silica powder was added to the mortar in Example 1.

[0047] Example 4

[0048] In Example 1, 20% of type F fly ash and 5% of silica fume were simultaneously added to the mortar.

[0049] Example 5

[0050] Low-heat silicate cement, with a C3A content of 1.32% and a C3S content of 30.25%.

[0051] The No. 5 fine aggregate is a mixture of pretreated aggregate and compliant aggregate, with the compliant aggregate comprising 40% by mass. The pretreated aggregate is made from No. 3 original rock after processing and pretreatment. The pretreatment steps are as follows: the initial aggregate is placed in a steam furnace and subjected to high-temperature steam oxidation at 200℃ and 1.2MPa for 3 hours. After the high-temperature steam oxidation is completed, it is water-quenched and dried to obtain pretreated aggregate with an SO3 content of 1.4% by mass. The particle size distribution of the pretreated aggregate and the No. 5 fine aggregate is shown in Table 3.

[0052] Table 3. Particle size distribution of pretreated aggregate and No. 5 fine aggregate

[0053] Cement, No. 5 fine aggregate, and water are mixed in a mass ratio of 1:2.5:0.5 to obtain mortar.

[0054] Example 6

[0055] In Example 5, 25% of type F fly ash was added to the mortar.

[0056] Example 7

[0057] In Example 5, 5% silica powder was added to the mortar.

[0058] Example 8

[0059] In Example 5, 20% of type F fly ash and 5% of silica fume were simultaneously added to the mortar.

[0060] Example 9

[0061] In Example 4, 3% of barium silicate was added to the mortar, which is a cementitious material.

[0062] Example 10

[0063] In Example 8, 5% of barium hydroxide, comprising the cementitious material, was added to the mortar.

[0064] Comparative Example 1

[0065] The difference from Example 1 is that the fine aggregate is No. 2 fine aggregate, and the particle size distribution of No. 2 fine aggregate is shown in Table 4.

[0066] Table 4. Particle size distribution of No. 2 fine aggregate

[0067] Cement, No. 2 fine aggregate, and water are mixed in a mass ratio of 1:2.5:0.5 to obtain mortar.

[0068] Comparative Example 2

[0069] The difference from Example 1 is that the fine aggregate is No. 1 fine aggregate, and the particle size distribution of No. 1 fine aggregate is shown in Table 5. The only difference between No. 1 fine aggregate and No. 2 fine aggregate is the particle size distribution.

[0070] Table 5. Particle size distribution of #1 fine aggregate

[0071] Cement, No. 1 fine aggregate, and water are mixed in a mass ratio of 1:2.5:0.5 to obtain mortar.

[0072] Comparative Example 3

[0073] 25% of type F fly ash was added to the mortar of Comparative Example 1.

[0074] Comparative Example 4

[0075] 5% silica powder was added to the mortar of Comparative Example 1.

[0076] Comparative Example 5

[0077] 25% of type F fly ash was added to the mortar of Comparative Example 2.

[0078] Comparative Example 6

[0079] 5% silica powder was added to the mortar of Comparative Example 2.

[0080] Comparative Example 7

[0081] The difference from Example 5 is that the fine aggregate used is No. 4 fine aggregate, which is made from No. 3 original rock after processing and pretreatment. The pretreatment steps are as follows: the initial aggregate is placed in a steam furnace and subjected to high-temperature steam oxidation at 200℃ and 1.2MPa for 3 hours. After the high-temperature steam oxidation is completed, it is water quenched and cooled, and then dried to obtain No. 4 fine aggregate with an SO3 mass content of 1.4%. The particle size distribution of No. 4 fine aggregate is shown in Table 6.

[0082] Table 6. Particle size distribution of #4 fine aggregate

[0083] Comparative Example 8

[0084] 25% of type F fly ash was added to the mortar of Comparative Example 7.

[0085] Comparative Example 9

[0086] 5% silica powder was added to the mortar of Comparative Example 7.

[0087] The mortar expansion rate of Examples 1-8 and Comparative Examples 1-9 at different ages was tested according to GB / T 749-2008 "Test Method for Sulfate Attack Resistance of Cement". The test results are shown in Tables 7-8.

[0088] Table 7. Mortar expansion rate test results for Examples 1-4, Example 9, and Comparative Examples 1-6

[0089] Table 8. Mortar expansion rate test results for Examples 5-8, Example 10, and Comparative Examples 7-9

[0090] As shown in Tables 7 and 8, by compounding high SO3-content initial / pretreated aggregates with low SO3-content compliant aggregates to produce fine aggregates (3# and 5# fine aggregates), and strictly controlling the particle size distribution of the initial aggregates, the mortar expansion rate can be significantly reduced. The 84-day expansion rate of the mortar in Example 1 is only 0.11%, significantly lower than that in Comparative Examples 1 and 2; the 84-day expansion rate of the mortar in Example 5 is 0.20%, significantly lower than that in Comparative Example 7; the addition of Class F fly ash or silica fume can significantly reduce the mortar expansion rate. The mortar expansion rates of Examples 2-4, which incorporate admixtures, are better than those in Example 1. Correspondingly, the mortar expansion rates of Comparative Examples 3-6 with admixtures are better than those of Comparative Examples 1-2; the mortar expansion rates of Examples 6-8 with admixtures are better than those of Example 5; and correspondingly, the mortar expansion rates of Comparative Examples 8-9 with admixtures are better than those of Comparative Example 7. The effect of adding silica fume on inhibiting mortar expansion rate is better than that of Class F fly ash. On this basis, the simultaneous addition of admixtures and sulfate curing agents, through the synergistic effect of aggregate gradation control, cementitious material optimization, and ion curing, has a significant inhibitory effect on resisting aggregate sulfate erosion. The mortar expansion rates of Examples 9 and 10 are significantly lower than those of the comparative examples.

[0091] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A method for inhibiting sulfate erosion of aggregates based on gradation control, cementitious material optimization, and synergistic ion curing, characterized in that, When the SO3 mass content in the initial aggregate is ≥0.5%, the initial aggregate is not used as coarse aggregate, but only as fine aggregate, and is applied to concrete or mortar. The fine aggregate is composed of initial aggregate and compliant aggregate, and the fineness modulus of the fine aggregate is 2.4~2.

8.

2. The method for inhibiting aggregate sulfate erosion based on gradation control, cementitious material optimization, and synergistic ion solidification as described in claim 1, characterized in that, When the SO3 mass content in the initial aggregate is 0.5~1.5%, the particle size distribution of the initial aggregate is controlled as follows: 5~2.5mm 30~35%, 2.5~1.25mm 25~30%, 1.25~0.63mm 25~30%, 0.63~0.32mm 7~12%, 0.32~0.16mm 5~8%, <0.16mm 0~3%, and the fineness modulus of the initial aggregate is 3.61~3.

84.

3. The method for inhibiting aggregate sulfate erosion based on gradation control, cementitious material optimization, and ion solidification synergy, as described in claim 1 or 2, is characterized in that... When the SO3 mass content in the initial aggregate is 1.5~2.5%, the process also includes pre-treatment of the initial aggregate to obtain pre-treated aggregate. The particle size distribution of the pre-treated aggregate is controlled as follows: 5~2.5mm 30~35%, 2.5~1.25mm 25~30%, 1.25~0.63mm 25~30%, 0.63~0.32mm 7~12%, 0.32~0.16mm 5~8%, <0.16mm 0~3%, and the fineness modulus of the pre-treated aggregate is 3.61~3.

84. The fine aggregate is composed of pretreated aggregate and compliant aggregate, and the fineness modulus of the fine aggregate is 2.4~2.

8.

4. The method for inhibiting aggregate sulfate erosion based on gradation control, cementitious material optimization, and synergistic ion solidification as described in claim 3, is characterized in that... The pretreatment includes high-temperature steam oxidation or microwave heat treatment, and the SO3 mass content in the pretreated aggregate is 0.5~1.5%.

5. The method for inhibiting aggregate sulfate erosion based on gradation control, cementitious material optimization, and ion solidification synergy, as described in claim 4, is characterized in that... The SO3 content in the compliant aggregate is less than 0.5%, and the mass fraction of compliant aggregate in the fine aggregate does not exceed 40%.

6. The method for inhibiting aggregate sulfate erosion based on gradation control, cementitious material optimization, and synergistic ion curing as described in claim 1 or 5, characterized in that, The cementitious material in the concrete or mortar includes cement and admixtures; The cement contains ≤2% by mass of tricalcium aluminate (C3A) and ≤35% by mass of tricalcium silicate (C3S).

7. The method for inhibiting aggregate sulfate erosion based on gradation control, cementitious material optimization, and ion solidification synergy as described in claim 6, characterized in that, The admixture comprises type F fly ash and / or silica fume.

8. The method for inhibiting aggregate sulfate erosion based on gradation control, cementitious material optimization, and ion solidification synergy, as described in claim 7, is characterized in that... When the admixture is Class F fly ash, the dosage is 20-30%; When the admixture is silicon powder, the dosage is 3-8%; When the admixture is type F fly ash and silica fume, the amount of type F fly ash is 20-25% and the amount of silica fume is 3-5%.

9. The method for inhibiting aggregate sulfate erosion based on synergistic effects of gradation control, cementitious material optimization, and ion curing as described in claim 7 or 8, characterized in that, The concrete or mortar also contains a sulfate curing agent, which is a barium salt, and the amount of sulfate curing agent is 3-5% of the cementitious material.

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