Island reef cement, its preparation process and application

Abstract

This invention discloses an island and reef cement, its preparation process, and its application, belonging to the field of cement technology. The island and reef cement is composed of the following components in parts by weight: silicate cement clinker: 30-80; active mineral admixture: 15-65; gypsum: 2.5-6. The active mineral admixture includes granulated blast furnace slag, fly ash, and coral powder with surface adsorption of amino alcohols, in a mass ratio of 5-55:5-35:5-40; or, the active mineral admixture includes granulated blast furnace slag and coral powder with surface adsorption of amino alcohols, in a mass ratio of 5-55:5-40; or, the active mineral admixture includes fly ash and coral powder with surface adsorption of amino alcohols, in a mass ratio of 5-35:5-40. The product of this invention has the significant characteristic of being able to be mixed and cured with both freshwater and seawater, possessing high early strength, stable later strength, and excellent resistance to seawater erosion, while also exhibiting good density and volume stability.

Description

Technical Field

[0001] This invention belongs to the field of cement technology, and relates to an island and reef cement, and more particularly to an island and reef cement, its preparation method and application. Background Technology

[0002] In recent years, the development of marine resources has received increasing attention, with particularly rapid development in marine engineering projects such as ports, seawalls, coastal protection, and airports on distant islands and reefs. This has led to a growing demand for marine engineering cementitious materials. However, transporting concrete materials, especially cementitious materials, to distant islands and reefs is extremely time-consuming, labor-intensive, and expensive. If materials could be sourced locally on these islands and reefs, transportation costs could be significantly reduced. Therefore, research on how to improve the local availability of cement raw materials for island and reef cement materials without compromising concrete performance is receiving increasing attention.

[0003] Cement and concrete structures used on offshore islands and reefs, especially in tidal and splash zones, are constantly exposed to seawater erosion. However, the seawater erosion and scouring resistance of ordinary cement cannot fully meet the special requirements of marine engineering. Currently, the widely used island and reef cement is based on silicate cement, with active admixtures including fly ash and blast furnace slag added to prepare seawater erosion resistant cement, such as GB / T 31289-2014 "Marine Silicate Cement". However, this type of cement has insufficient corrosion resistance due to its slow early hydration rate, and can only be mixed and cured with fresh water, not seawater. At the same time, this type of cement cannot solve the risk of steel corrosion in marine concrete. Therefore, the market expects island and reef cement with better early strength and durability. Summary of the Invention

[0004] This invention addresses the problems of low transportation efficiency, high cost, slow strength formation, and steel corrosion of cement-based materials used in offshore island and reef construction. It provides a low-cost and highly durable cement suitable for offshore island and reef engineering projects, which can be partially sourced locally and can be mixed and cured with both fresh and seawater.

[0005] To achieve the above objectives, the present invention provides an island and reef cement, characterized in that the island and reef cement is composed of the following components in parts by weight: silicate cement clinker: 30-80; active mineral admixture: 15-65; gypsum: 2.5-6; wherein the active mineral admixture comprises granulated blast furnace slag, fly ash, and coral powder with surface adsorption of amino alcohols, and the mass ratio of granulated blast furnace slag, fly ash, and coral powder with surface adsorption of amino alcohols is 5-55:5-35:5-40; or, the active mineral admixture comprises granulated blast furnace slag and coral powder with surface adsorption of amino alcohols, and the mass ratio of granulated blast furnace slag and coral powder with surface adsorption of amino alcohols is 5-55:5-40; or, the active mineral admixture comprises fly ash and coral powder with surface adsorption of amino alcohols, and the mass ratio of fly ash and coral powder with surface adsorption of amino alcohols is 5-35:5-40.

[0006] Furthermore, the present invention provides a reef cement that may also have the following characteristics: wherein the coral powder with surface adsorbed amino alcohols is obtained by mixing and grinding coral reef sand with an amino alcohol grinding aid.

[0007] Furthermore, the present invention provides an island and reef cement that may also have the following characteristics: wherein the amino alcohol grinding aid is triethylalkanolamine, dimethylalkanolamine, or a mixture of triethylalkanolamine and dimethylalkanolamine in a mass ratio of 1 to 5: 1 to 5.

[0008] Furthermore, the present invention provides a reef cement that may also have the following characteristics: wherein the mass ratio of the coral reef sand to the amino alcohol grinding aid is 5-40:0.5-2.

[0009] Furthermore, the present invention provides an island and reef cement, which may also have the following characteristics: wherein the silicate cement clinker comprises tricalcium silicate (C3S), dicalcium silicate (β-C2S), tricalcium aluminate (C3A), and tetracalcium aluminoferrite (C4AF); the mass ratio of tricalcium silicate, dicalcium silicate, tricalcium aluminate, and tetracalcium aluminoferrite is 36-70:15-37:7-15:10-18.

[0010] Furthermore, the present invention provides an island and reef cement, which may also have the following feature: wherein the granulated blast furnace slag is of grade S95 or above.

[0011] Furthermore, the present invention provides a reef cement that may also have the following feature: the fly ash is of grade II or above.

[0012] Furthermore, the present invention provides an island and reef cement that also has the following characteristic: wherein the specific surface area of ​​the granulated blast furnace slag, fly ash, and coral powder with surface adsorbed amino alcohols after grinding is not less than 350 m². 2 / kg; preferably, the specific surface area of ​​the finely ground granulated blast furnace slag, fly ash, and coral powder with surface adsorbed amino alcohols is not less than 400 m². 2 / kg.

[0013] This invention also provides a process for preparing island and reef cement, characterized by the following steps: Step 1, mixing crushed coral reef sand with an amino alcohol-based grinding aid, so that the surface of the coral powder adsorbs the amino alcohol, and mixing until the specific surface area of ​​the coral powder with adsorbed amino alcohol is not less than 300 m². 2 / kg; Granulated blast furnace slag and / or fly ash are first crushed and then ground separately to a specific surface area of ​​not less than 300 m². 2 / kg; Step 2: Add silicate cement clinker, gypsum, and the finely ground active mineral admixtures from Step 1 to a mixing mill according to the specified weight proportions, and mix and grind them a second time until the specific surface area is not less than 310m². 2 / kg, producing finished cement products for islands and reefs.

[0014] This invention also provides a method for applying island and reef cement, characterized in that: when the island and reef cement is mixed with sand or coral reef sand to prepare mortar or concrete, it is mixed and cured with fresh water or with seawater; the mortar or concrete mixed and cured with fresh water is used for reinforced concrete structures, such as buildings and bridges; the mortar or concrete mixed and cured with seawater is used for plain concrete structures, such as breakwaters, roads and wave-dissipating blocks on ocean islands and reefs.

[0015] The beneficial effects of this invention are as follows:

[0016] I. The raw material for the coral micropowder required for the product of this invention can be obtained directly from coral reef sand on the islands and reefs to be constructed; in addition, with a strong durability design, it has been verified through experiments that it can be mixed with local seawater on the islands and reefs; the localization of raw materials is greatly improved, which significantly reduces the amount of cementitious materials transported to the ocean islands and reefs, reduces the cost of island and reef marine engineering construction, and has significant convenience and economic benefits, meeting the needs of ocean engineering construction.

[0017] Second, the product of this invention has early strength and rapid hardening, and its strength continues to increase in the later stage, which is beneficial to improving the safety and durability of reinforced concrete in use.

[0018] Third, the cement mortar or concrete prepared by the product of this invention can effectively slow down the corrosion of steel bars for a long time, and has the characteristics of being able to be mixed and cured with both fresh water and seawater.

[0019] Fourth, the cement concrete structure prepared by the product of this invention has excellent density and volume stability; it can improve the impermeability of concrete, and has high resistance to chloride ion diffusion, sulfate erosion, seawater corrosion and steel reinforcement corrosion prevention performance, thus meeting the needs of marine engineering construction.

[0020] V. This invention uses amino alcohol as a grinding aid for coral micron powder. After achieving the grinding aid function in the coral reef sand grinding stage, it can continue to play the role of steel reinforcement corrosion prevention in island and reef cement, thus achieving steel reinforcement corrosion prevention in concrete. Attached Figure Description

[0021] Figure 1 This is a flow chart of the preparation process of the island and reef cement of the present invention;

[0022] Figure 2 The particle size distribution curves of finely ground granulated blast furnace slag, fly ash, and coral powder with surface adsorbed amino alcohols in the island and reef cement of this invention are shown.

[0023] Figure 3 This is a scanning electron microscope image of coral powder in the island and reef cement of the present invention;

[0024] Figure 4 This is an analysis of the hydration products of island and reef cement (containing different amounts of surface-adsorbed amino alcohols) in different embodiments of the present invention, wherein a is the hydration product of island and reef cement slurry after 28 days in Example 26, b is the hydration product of island and reef cement slurry after 28 days in Example 27, c is the hydration product of island and reef cement slurry after 28 days in Example 30, and d is the hydration product of island and reef cement slurry after 28 days in Example 35.

[0025] Figure 5 These are scanning electron microscope (SEM) images of island and reef cement (containing different amounts of active mineral admixtures) from different embodiments of the present invention at different ages, where a is an SEM image of island and reef cement of Example 28 and b is an SEM image of island and reef cement of Example 31.

[0026] Figure 6 The graphs show the steel corrosion current density test results of the island cement-mixed concrete of different embodiments and comparative examples of the present invention after 365 days of seawater exposure (concrete mix ratio: 800 kg of island cement, 224 kg of water, 860 kg of fine aggregate, and 369 kg of coarse aggregate per cubic meter). Among them, a is the steel corrosion current density test result graph of the island cement-mixed concrete of Example 1 and Comparative Examples 1-3, and b is the steel corrosion current density test result graph of the island cement-mixed concrete of Example 33 and Comparative Example 33. Detailed Implementation

[0027] The present invention will be further described below with reference to specific embodiments.

[0028] Example 1

[0029] This embodiment provides an island reef cement, composed of the following parts by weight: 32 parts silicate cement clinker, 3 parts anhydrite, 25 parts granulated blast furnace slag, 35 parts fly ash, and 5 parts coral powder with surface-adsorbed amino alcohols (4.5 parts coral powder and 0.5 parts amino alcohol grinding aid are mixed and ground together; the amino alcohol grinding aid is a mixture of triethylalkanolamine and dimethylalkanolamine in a mass ratio of 1:1). Its preparation process includes the following steps: Step 1: Crush the coral reef sand, mix with the amino alcohol grinding aid, and perform initial grinding until the specific surface area is ≥400 m². 2 / kg, while granulated blast furnace slag and fly ash are first crushed and then ground separately to a specific surface area ≥400m². 2 / kg; Step 2: Add silicate cement clinker, anhydrite, and the granulated blast furnace slag, fly ash, and surface-adsorbed amino alcohol coral powder to a mixing mill according to the weight proportions in Step 1, and mix and grind them twice until the specific surface area is ≥340m². 2 / kg, producing finished cement for islands and reefs. The setting time and strength test results of the mortar specimens after mixing and curing with fresh water are shown in Table 1.

[0030] Comparative Example 1-1 (without coral powder, but with amino alcohol additives)

[0031] This comparative example provides an island and reef cement, composed of the following parts by weight: 37 parts silicate cement clinker (same as in Example 1), 3 parts anhydrite, 25 parts granulated blast furnace slag, 34.5 parts fly ash, and 0.5 parts amino alcohol admixture (same as the amino alcohol grinding aid in Example 1). Its preparation process includes the following steps: Step 1, the granulated blast furnace slag and fly ash are first crushed and then ground separately to a specific surface area ≥ 400 m². 2 / kg; Step 2: Add silicate cement clinker, anhydrite, and the finely ground granulated blast furnace slag, fly ash, and amino alcohol additives from Step 1 to a mixing mill according to the specified weight proportions, and mix and grind them twice until the specific surface area is ≥340m². 2 / kg, producing finished cement for islands and reefs. Amino alcohol admixtures are added as rust inhibitors. The setting time and strength test results of the mortar specimens after mixing and curing with fresh water are shown in Table 1.

[0032] Comparative Examples 1-2 (containing coral powder and amino alcohol additives, but the amino alcohol additives are not added in advance as grinding aids, but only as rust inhibitors)

[0033] This comparative example provides an island reef cement, composed of the following parts by weight: 32 parts silicate cement clinker (same as in Example 1), 3 parts anhydrite, 25 parts granulated blast furnace slag, 35 parts fly ash, 4.5 parts coral powder, and 0.5 parts amino alcohol admixture (same as the amino alcohol grinding aid in Example 1). Its preparation process includes the following steps: Step 1, the coral reef sand, granulated blast furnace slag, and fly ash are first crushed and then ground separately to a specific surface area ≥ 400 m². 2 / kg; Step 2: Add silicate cement clinker, anhydrite, amino alcohol grinding aid (as a rust inhibitor), and the granulated blast furnace slag, fly ash, and coral powder ground in Step 1 to a mixing mill according to the weight proportions, and mix and grind evenly until the specific surface area is ≥340m². 2 / kg, producing finished cement for islands and reefs. Amino alcohol admixtures are added as rust inhibitors. The setting time and strength test results of the mortar specimens after mixing and curing with fresh water are shown in Table 1.

[0034] Comparative Examples 1-3 (containing coral powder, but without amino alcohol grinding aids)

[0035] This comparative example provides an island reef cement, composed of the following parts by weight: 32 parts silicate cement clinker (same as Example 1), 3 parts anhydrite, 25 parts granulated blast furnace slag, 35 parts fly ash, and 4.5 parts coral powder. Its preparation process includes the following steps: Step 1: The coral reef sand, granulated blast furnace slag, and fly ash are first crushed and then ground separately to a specific surface area ≥ 400 m². 2 / kg; Step 2: Add silicate cement clinker, anhydrite, and the finely ground granulated blast furnace slag, fly ash, and coral powder from Step 1 to a mixing mill according to the specified weight proportions, and mix and grind them a second time until the specific surface area is ≥340m². 2 / kg, producing finished cement for islands and reefs. The setting time and strength test results of the mortar specimens after mixing and curing with fresh water are shown in Table 1.

[0036] Example 2

[0037] This embodiment provides an island reef cement, composed of the following parts by weight: 45 parts silicate cement clinker (same as in Example 1), 5 parts anhydrite, 5 parts granulated blast furnace slag, 5 parts fly ash, and 40 parts coral powder with surface-adsorbed amino alcohols (38 parts coral powder are mixed and ground with 2 parts amino alcohol grinding aid, the amino alcohol grinding aid being a mixture of triethylalkanolamine and dimethylalkanolamine in a mass ratio of 5:1). Its preparation process includes the following steps: Step 1: Crush the coral reef sand, mix with the amino alcohol grinding aid, and perform initial grinding until the specific surface area is ≥430 m². 2 / kg, while granulated blast furnace slag and fly ash are first crushed and then ground separately to a specific surface area ≥430m². 2 / kg; Step 2: Add silicate cement clinker, anhydrite, and the finely ground granulated blast furnace slag, fly ash, and surface-adsorbed amino alcohol coral powder to a mixing mill according to the weight proportions, and mix and grind twice until the specific surface area is ≥320m². 2 / kg, producing finished cement for islands and reefs. The setting time and strength test results of the mortar specimens after mixing and curing with fresh water are shown in Table 1.

[0038] Example 3

[0039] This embodiment provides an island reef cement, composed of the following parts by weight: 32 parts silicate cement clinker (same as in Example 1), 3 parts anhydrite, 55 parts granulated blast furnace slag, 5 parts fly ash, and 5 parts coral powder with surface-adsorbed amino alcohols (4.5 parts coral powder and 0.5 parts amino alcohol grinding aid are mixed and ground together; the amino alcohol grinding aid is a mixture of triethylalkanolamine and dimethylalkanolamine in a mass ratio of 3:1). Its preparation process includes the following steps: Step 1: Crush the coral reef sand, mix with the amino alcohol grinding aid, and perform initial grinding until the specific surface area is ≥400 m². 2 / kg, while granulated blast furnace slag and fly ash are first crushed and then ground separately to a specific surface area ≥400m². 2 / kg; Step 2: Add silicate cement clinker, anhydrite, granulated blast furnace slag, fly ash, and surface-adsorbed amino alcohol coral powder to a mixing mill according to the weight proportions in Step 1, and mix and grind twice until the specific surface area is ≥400m². 2 / kg, producing finished cement for islands and reefs. The setting time and strength test results of the mortar specimens after mixing and curing with fresh water are shown in Table 1.

[0040] Example 4

[0041] This embodiment provides an island reef cement, composed of the following parts by weight: 32 parts silicate cement clinker (same as in Example 1), 3 parts anhydrite, 25 parts granulated blast furnace slag, 35 parts fly ash, and 5 parts coral powder with surface-adsorbed amino alcohols (4.5 parts coral powder and 0.5 parts amino alcohol grinding aid are mixed and ground together; the amino alcohol grinding aid is a mixture of triethylalkanolamine and dimethylalkanolamine in a mass ratio of 2:1). Its preparation process includes the following steps: Step 1: Crush the coral reef sand, mix with the amino alcohol grinding aid, and perform initial grinding until the specific surface area is ≥385 m². 2 / kg, while granulated blast furnace slag and fly ash are first crushed and then ground separately to a specific surface area ≥450m². 2 / kg and 400m 2 / kg; Step 2: Add silicate cement clinker, anhydrite, granulated blast furnace slag, fly ash, and surface-adsorbed amino alcohol coral powder to a mixing mill according to the weight proportions in Step 1, and mix and grind twice until the specific surface area is ≥380m². 2 / kg, producing finished cement for islands and reefs. The setting time and strength test results of the mortar specimens after mixing and curing with fresh water are shown in Table 1.

[0042] Example 5

[0043] This embodiment provides an island reef cement, composed of the following parts by weight: 45 parts silicate cement clinker (same as in Example 1), 5 parts anhydrite, 5 parts granulated blast furnace slag, 5 parts fly ash, and 40 parts coral powder with surface-adsorbed amino alcohols (38 parts coral powder are mixed and ground with 2 parts amino alcohol grinding aid, the amino alcohol grinding aid being triethylalkanolamine). Its preparation process includes the following steps: Step 1: Crush the coral reef sand, mix with the amino alcohol grinding aid, and perform initial grinding until the specific surface area is ≥390 m² / g. 2 / kg, while granulated blast furnace slag and fly ash are first crushed and then ground separately to a specific surface area ≥420m². 2 / kg and 410m 2 / kg; Step 2: Add silicate cement clinker, anhydrite, and the granulated blast furnace slag, fly ash, and surface-adsorbed amino alcohol coral powder to a mixing mill according to the weight proportions in Step 1, and mix and grind them twice until the specific surface area is ≥350m². 2 / kg, producing finished cement for islands and reefs. The setting time and strength test results of the mortar specimens after mixing and curing with fresh water are shown in Table 1.

[0044] Example 6

[0045] This embodiment provides an island reef cement, composed of the following parts by weight: 32 parts silicate cement clinker (same as in Example 1), 3 parts anhydrite, 55 parts granulated blast furnace slag, 5 parts fly ash, and 5 parts coral powder with surface-adsorbed amino alcohols (4.5 parts coral powder and 0.5 parts amino alcohol grinding aid are mixed and ground together; the amino alcohol grinding aid is dimethylolamine). Its preparation process includes the following steps: Step 1: Crush the coral reef sand, mix with the amino alcohol grinding aid, and perform initial grinding until the specific surface area is ≥325 m² / g. 2 / kg, while granulated blast furnace slag and fly ash are first crushed and then ground separately to a specific surface area ≥410m². 2 / kg and 398m 2 / kg; Step 2: Add silicate cement clinker, anhydrite, and the granulated blast furnace slag, fly ash, and surface-adsorbed amino alcohol coral powder to a mixing mill according to the weight proportions in Step 1, and mix and grind them evenly until the specific surface area is ≥410m². 2 / kg, producing finished cement for islands and reefs. The setting time and strength test results of the mortar specimens after mixing and curing with fresh water are shown in Table 1.

[0046] Example 7

[0047] This embodiment provides an island reef cement, composed of the following parts by weight: 32 parts silicate cement clinker (same as in Example 1), 3 parts anhydrite, 25 parts granulated blast furnace slag, 35 parts fly ash, and 5 parts coral powder. Its preparation process includes the following steps: Step 1: Crush the coral reef sand and initially grind it to a specific surface area ≥ 400 m². 2 / kg, while granulated blast furnace slag and fly ash are first crushed and then ground separately to a specific surface area ≥400m². 2 / kg; Step 2: Add silicate cement clinker, anhydrite, and the granulated blast furnace slag, fly ash, and coral powder ground in Step 1 to a mixing mill according to the specified weight proportions, and mix and grind them a second time until the specific surface area is ≥395m². 2 / kg, producing finished cement for islands and reefs. The setting time and strength test results of mortar specimens using seawater mixing and curing are shown in Table 1.

[0048] Example 8

[0049] This embodiment provides an island reef cement, composed of the following parts by weight: 45 parts silicate cement clinker (same as in Example 1), 5 parts anhydrite, 5 parts granulated blast furnace slag, 5 parts fly ash, and 40 parts coral powder. Its preparation process includes the following steps: Step 1: Crush the coral reef sand and initially grind it to a specific surface area ≥ 400 m². 2 / kg, while granulated blast furnace slag and fly ash are first crushed and then ground separately to a specific surface area ≥430m². 2 / kg; Step 2: Add silicate cement clinker, anhydrite, and the finely ground granulated blast furnace slag, fly ash, and coral powder from Step 1 to a mixing mill according to the specified weight proportions, and mix and grind them twice until the specific surface area is ≥410m². 2 / kg, producing finished cement for islands and reefs. The setting time and strength test results of mortar specimens using seawater mixing and curing are shown in Table 1.

[0050] Example 9

[0051] This embodiment provides an island reef cement, composed of the following parts by weight: 32 parts silicate cement clinker (same as in Example 1), 3 parts anhydrite, 55 parts granulated blast furnace slag, 5 parts fly ash, and 5 parts coral powder. Its preparation process includes the following steps: Step 1: Crush the coral reef sand and initially grind it to a specific surface area ≥ 400 m². 2 / kg, while granulated blast furnace slag and fly ash are first crushed and then ground separately to a specific surface area ≥440m². 2 / kg; Step 2: Add silicate cement clinker, anhydrite, and the finely ground granulated blast furnace slag, fly ash, and coral powder from Step 1 to a mixing mill according to the specified weight proportions, and mix and grind them twice until the specific surface area is ≥45m². 2 / kg, producing finished cement for islands and reefs. The setting time and strength test results of mortar specimens using seawater mixing and curing are shown in Table 1.

[0052] Example 10

[0053] This embodiment provides an island reef cement, composed of the following parts by weight: 32 parts silicate cement clinker (same as in Example 1), 3 parts anhydrite, 25 parts granulated blast furnace slag, 35 parts fly ash, and 5 parts coral powder. Its preparation process includes the following steps: Step 1: Crush the coral reef sand and initially grind it to a specific surface area ≥ 400 m². 2 / kg, while granulated blast furnace slag and fly ash are first crushed and then ground separately to a specific surface area ≥430m². 2 / kg; Step 2: Add silicate cement clinker, anhydrite, and the finely ground granulated blast furnace slag, fly ash, and coral powder from Step 1 to a mixing mill according to the specified weight proportions, and mix and grind them a second time until the specific surface area is ≥310m². 2 / kg, producing finished cement for islands and reefs. The setting time and strength test results of mortar specimens using seawater mixing and curing are shown in Table 1.

[0054] Example 11

[0055] This embodiment provides an island reef cement, composed of the following parts by weight: 45 parts silicate cement clinker (same as in Example 1), 5 parts anhydrite, 5 parts granulated blast furnace slag, 5 parts fly ash, and 40 parts coral powder. Its preparation process includes the following steps: Step 1: Crush the coral reef sand and initially grind it to a specific surface area ≥ 400 m². 2 / kg, while granulated blast furnace slag and fly ash are first crushed and then ground separately to a specific surface area ≥470m². 2 / kg and 430m 2 / kg; Step 2: Add silicate cement clinker, anhydrite, and the finely ground granulated blast furnace slag, fly ash, and coral powder from Step 1 to a mixing mill according to the specified weight proportions, and mix and grind them a second time until the specific surface area is ≥434m². 2 / kg, producing finished cement for islands and reefs. The setting time and strength test results of mortar specimens using seawater mixing and curing are shown in Table 1.

[0056] Example 12

[0057] This embodiment provides an island reef cement, composed of the following parts by weight: 32 parts silicate cement clinker (same as in Example 1), 3 parts anhydrite, 55 parts granulated blast furnace slag, 5 parts fly ash, and 5 parts coral powder. Its preparation process includes the following steps: Step 1: Crush the coral reef sand and initially grind it to a specific surface area ≥ 335 m². 2 / kg, while granulated blast furnace slag and fly ash are first crushed and then ground separately to a specific surface area ≥430m². 2 / kg; Step 2: Add silicate cement clinker, anhydrite, and the finely ground granulated blast furnace slag, fly ash, and coral powder from Step 1 to a mixing mill according to the specified weight proportions, and mix and grind them a second time until the specific surface area is ≥360m². 2 / kg, producing finished cement for islands and reefs. The setting time and strength test results of mortar specimens using seawater mixing and curing are shown in Table 1.

[0058] Example 13

[0059] This embodiment provides an island reef cement, composed of the following parts by weight: 32 parts silicate cement clinker (same as in Example 1), 3 parts anhydrite, 55 parts granulated blast furnace slag, 5 parts fly ash, and 5 parts coral powder with surface-adsorbed amino alcohols (4.5 parts coral powder and 0.5 parts amino alcohol grinding aid are mixed and ground together; the amino alcohol grinding aid is the same as in Example 1). Its preparation process includes the following steps: Step 1: Crush the coral reef sand, mix with the amino alcohol grinding aid, and perform initial grinding until the specific surface area is ≥420 m². 2 / kg, while granulated blast furnace slag and fly ash are first crushed and then ground separately to a specific surface area ≥420m². 2 / kg; Step 2: Add silicate cement clinker, anhydrite, and the granulated blast furnace slag, fly ash, and surface-adsorbed amino alcohol coral powder to a mixing mill according to the weight proportions in Step 1, and mix and grind them twice until the specific surface area is ≥365m². 2 / kg, producing finished cement for islands and reefs. The setting time and strength test results of the mortar specimens after mixing and curing with fresh water are shown in Table 1.

[0060] Example 14

[0061] This embodiment provides an island reef cement, composed of the following parts by weight: 70 parts silicate cement clinker (same as in Example 1), 5 parts anhydrite, 15 parts granulated blast furnace slag, 5 parts fly ash, and 5 parts coral powder with surface-adsorbed amino alcohols (4.5 parts coral powder and 0.5 parts amino alcohol grinding aid are mixed and ground together; the amino alcohol grinding aid is the same as in Example 2). Its preparation process includes the following steps: Step 1: Crush the coral reef sand, mix with the amino alcohol grinding aid, and perform initial grinding until the specific surface area is ≥440 m². 2 / kg, while granulated blast furnace slag and fly ash are first crushed and then ground separately to a specific surface area ≥440m². 2 / kg; Step 2: Add silicate cement clinker, anhydrite, and the granulated blast furnace slag, fly ash, and surface-adsorbed amino alcohol coral powder to a mixing mill according to the weight proportions in Step 1, and mix and grind them twice until the specific surface area is ≥420m². 2 / kg, producing finished cement for islands and reefs. The setting time and strength test results of the mortar specimens after mixing and curing with fresh water are shown in Table 1.

[0062] Example 15

[0063] This embodiment provides an island reef cement, composed of the following parts by weight: 70 parts silicate cement clinker (same as in Example 1), 5 parts anhydrite, 5 parts granulated blast furnace slag, 5 parts fly ash, and 15 parts coral powder with surface-adsorbed amino alcohols (14 parts coral powder are mixed and ground with 1 part amino alcohol grinding aid, the amino alcohol grinding aid is the same as in Example 3). Its preparation process includes the following steps: Step 1: Crush the coral reef sand, mix with the amino alcohol grinding aid, and perform initial grinding until the specific surface area is ≥395 m². 2 / kg, while granulated blast furnace slag and fly ash are first crushed and then ground separately to a specific surface area ≥395m². 2 / kg; Step 2: Add silicate cement clinker, anhydrite, granulated blast furnace slag, fly ash, and surface-adsorbed amino alcohol coral powder to a mixing mill according to the weight proportions in Step 1, and mix and grind twice until the specific surface area is ≥460m². 2 / kg, producing finished cement for islands and reefs. The setting time and strength test results of the mortar specimens after mixing and curing with fresh water are shown in Table 1.

[0064] Example 16

[0065] This embodiment provides an island reef cement, composed of the following parts by weight: 47 parts silicate cement clinker (same as in Example 1), 8 parts anhydrite, 10 parts granulated blast furnace slag, 10 parts fly ash, and 25 parts coral powder with surface-adsorbed amino alcohols (23.5 parts coral powder and 1.5 parts amino alcohol grinding aid are mixed and ground together; the amino alcohol grinding aid is the same as in Example 4). Its preparation process includes the following steps: Step 1: Crush the coral reef sand, mix with the amino alcohol grinding aid, and perform initial grinding until the specific surface area is ≥345 m². 2 / kg, while granulated blast furnace slag and fly ash are first crushed and then ground separately to a specific surface area ≥470m². 2 / kg and 430m 2 / kg; Step 2: Add silicate cement clinker, anhydrite, and the granulated blast furnace slag, fly ash, and surface-adsorbed amino alcohol coral powder to a mixing mill according to the weight proportions in Step 1, and mix and grind them twice until the specific surface area is ≥394m². 2 / kg, producing finished cement for islands and reefs. The setting time and strength test results of the mortar specimens after mixing and curing with fresh water are shown in Table 1.

[0066] Example 17

[0067] This embodiment provides an island reef cement, composed of the following parts by weight: 70 parts silicate cement clinker (same as in Example 1), 5 parts anhydrite, 15 parts granulated blast furnace slag, 5 parts fly ash, and 5 parts coral powder with surface-adsorbed amino alcohols (4.5 parts coral powder and 0.5 parts amino alcohol grinding aid are mixed and ground together; the amino alcohol grinding aid is the same as in Example 5). Its preparation process includes the following steps: Step 1: Crush the coral reef sand, mix with the amino alcohol grinding aid, and perform initial grinding until the specific surface area is ≥335 m². 2 / kg, while granulated blast furnace slag and fly ash are first crushed and then ground separately to a specific surface area ≥350m². 2 / kg and 450m 2 / kg; Step 2: Add silicate cement clinker, anhydrite, granulated blast furnace slag, fly ash, and surface-adsorbed amino alcohol coral powder to a mixing mill according to the weight proportions in Step 1, and mix and grind twice until the specific surface area is ≥433m². 2 / kg, producing finished cement for islands and reefs. The setting time and strength test results of the mortar specimens after mixing and curing with fresh water are shown in Table 1.

[0068] Example 18

[0069] This embodiment provides an island reef cement, composed of the following parts by weight: 70 parts silicate cement clinker (same as in Example 1), 5 parts anhydrite, 5 parts granulated blast furnace slag, 5 parts fly ash, and 15 parts coral powder with surface-adsorbed amino alcohols (14 parts coral powder are mixed and ground with 1 part amino alcohol grinding aid, the amino alcohol grinding aid is the same as in Example 6). Its preparation process includes the following steps: Step 1: Crush the coral reef sand, mix with the amino alcohol grinding aid, and perform initial grinding until the specific surface area is ≥405 m². 2 / kg, while granulated blast furnace slag and fly ash are first crushed and then ground separately to a specific surface area ≥430m². 2 / kg and 365m 2 / kg; Step 2: Add silicate cement clinker, anhydrite, and the granulated blast furnace slag, fly ash, and surface-adsorbed amino alcohol coral powder to a mixing mill according to the weight proportions in Step 1, and mix and grind them twice until the specific surface area is ≥330m². 2 / kg, producing finished cement for islands and reefs. The setting time and strength test results of the mortar specimens after mixing and curing with fresh water are shown in Table 1.

[0070] Example 19

[0071] This embodiment provides an island reef cement, composed of the following parts by weight: 47 parts silicate cement clinker (same as in Example 1), 8 parts anhydrite, 10 parts granulated blast furnace slag, 10 parts fly ash, and 25 parts coral powder. Its preparation process includes the following steps: Step 1: Crush the coral reef sand and initially grind it to a specific surface area ≥ 405 m². 2 / kg, while granulated blast furnace slag and fly ash are first crushed and then ground separately to a specific surface area ≥430m². 2 / kg and 365m 2 / kg; Step 2: Add silicate cement clinker, anhydrite, and the finely ground granulated blast furnace slag, fly ash, and coral powder from Step 1 to a mixing mill according to the specified weight proportions, and mix and grind them a second time until the specific surface area is ≥418m². 2 / kg, producing finished cement for islands and reefs. The setting time and strength test results of mortar specimens using seawater mixing and curing are shown in Table 1.

[0072] Comparative Example 19-1 (Comparison without Coral Powder)

[0073] This comparative example provides an island and reef cement, composed of the following parts by weight: 72 parts silicate cement clinker (same as in Example 1), 8 parts anhydrite, 10 parts granulated blast furnace slag, and 10 parts fly ash. Its preparation process includes the following steps: Step 1: The granulated blast furnace slag and fly ash are first crushed and then ground separately to a specific surface area ≥ 430 m². 2 / kg and 365m 2 / kg; Step 2: Add silicate cement clinker, anhydrite, and the finely ground granulated blast furnace slag and fly ash from Step 1 to a mixing mill according to the specified weight proportions, and mix and grind them twice until the specific surface area is ≥418m². 2 / kg, producing finished cement for islands and reefs. The setting time and strength test results of mortar specimens using seawater mixing and curing are shown in Table 1.

[0074] Example 20

[0075] This embodiment provides an island reef cement, composed of the following parts by weight: 70 parts silicate cement clinker (same as in Example 1), 5 parts anhydrite, 15 parts granulated blast furnace slag, 5 parts fly ash, and 5 parts coral powder. Its preparation process includes the following steps: Step 1: Crush the coral reef sand and initially grind it to a specific surface area ≥ 430 m². 2 / kg, while granulated blast furnace slag and fly ash are first crushed and then ground separately to a specific surface area ≥430m². 2 / kg and 365m 2 / kg; Step 2: Add silicate cement clinker, anhydrite, and the granulated blast furnace slag, fly ash, and coral powder ground in Step 1 to a mixing mill according to the specified weight proportions, and mix and grind them a second time until the specific surface area is ≥420m². 2 / kg, producing finished cement for islands and reefs. The setting time and strength test results of mortar specimens using seawater mixing and curing are shown in Table 1.

[0076] Example 21

[0077] This embodiment provides an island reef cement, composed of the following parts by weight: 70 parts silicate cement clinker (same as in Example 1), 5 parts anhydrite, 5 parts granulated blast furnace slag, 5 parts fly ash, and 15 parts coral powder. Its preparation process includes the following steps: Step 1: Crush the coral reef sand and initially grind it to a specific surface area ≥ 390 m². 2 / kg, while granulated blast furnace slag and fly ash are first crushed and then ground separately to a specific surface area ≥390m². 2 / kg; Step 2: Add silicate cement clinker, anhydrite, and the finely ground granulated blast furnace slag, fly ash, and coral powder from Step 1 to a mixing mill according to the specified weight proportions, and mix and grind them a second time until the specific surface area is ≥380m². 2 / kg, producing finished cement for islands and reefs. The setting time and strength test results of mortar specimens using seawater mixing and curing are shown in Table 1.

[0078] Example 22

[0079] This embodiment provides an island reef cement, composed of the following parts by weight: 47 parts silicate cement clinker (same as in Example 1), 8 parts anhydrite, 10 parts granulated blast furnace slag, 10 parts fly ash, and 25 parts coral powder. Its preparation process includes the following steps: Step 1: Crush the coral reef sand and initially grind it to a specific surface area ≥ 405 m². 2 / kg, while granulated blast furnace slag and fly ash are first crushed and then ground separately to a specific surface area ≥405m². 2 / kg and 430m 2 / kg; Step 2: Add silicate cement clinker, anhydrite, and the granulated blast furnace slag, fly ash, and coral powder ground in Step 1 to a mixing mill according to the specified weight proportions, and mix and grind them a second time until the specific surface area is ≥390m². 2 / kg, producing finished cement for islands and reefs. The setting time and strength test results of mortar specimens using seawater mixing and curing are shown in Table 1.

[0080] Example 23

[0081] This embodiment provides an island reef cement, composed of the following parts by weight: 70 parts silicate cement clinker (same as in Example 1), 5 parts anhydrite, 15 parts granulated blast furnace slag, 5 parts fly ash, and 5 parts coral powder. Its preparation process includes the following steps: Step 1: Crush the coral reef sand and initially grind it to a specific surface area ≥ 410 m². 2 / kg, while granulated blast furnace slag and fly ash are first crushed and then ground separately to a specific surface area ≥464m². 2 / kg and 374m 2 / kg; Step 2: Add silicate cement clinker, anhydrite, and the finely ground granulated blast furnace slag, fly ash, and coral powder from Step 1 to a mixing mill according to the specified weight proportions, and mix and grind them a second time until the specific surface area is ≥378m².2 / kg, producing finished cement for islands and reefs. The setting time and strength test results of mortar specimens using seawater mixing and curing are shown in Table 1.

[0082] Example 24

[0083] This embodiment provides an island reef cement, composed of the following parts by weight: 70 parts silicate cement clinker (same as in Example 1), 5 parts anhydrite, 5 parts granulated blast furnace slag, 5 parts fly ash, and 15 parts coral powder. Its preparation process includes the following steps: Step 1: Crush the coral reef sand and initially grind it to a specific surface area ≥ 405 m². 2 / kg, while granulated blast furnace slag and fly ash are first crushed and then ground separately to a specific surface area ≥395m². 2 / kg and 420m 2 / kg; Step 2: Add silicate cement clinker, anhydrite, and the granulated blast furnace slag, fly ash, and coral powder ground in Step 1 to a mixing mill according to the specified weight parts, and mix and grind them a second time until the specific surface area is ≥473m². 2 / kg, producing finished cement for islands and reefs. The setting time and strength test results of mortar specimens using seawater mixing and curing are shown in Table 1.

[0084] Example 25

[0085] This embodiment provides an island reef cement, composed of the following parts by weight: 47 parts silicate cement clinker (same as in Example 1), 3 parts anhydrite, 45 parts granulated blast furnace slag, and 5 parts coral powder with surface-adsorbed amino alcohols (4.5 parts coral powder and 0.5 parts amino alcohol grinding aid are mixed and ground together; the amino alcohol grinding aid is the same as in Example 1). Its preparation process includes the following steps: Step 1: Crush the coral reef sand, mix with the amino alcohol grinding aid, and perform initial grinding until the specific surface area is ≥400 m². 2 / kg, while granulated blast furnace slag is first crushed and ground to a specific surface area ≥400m². 2 / kg; Step 2: Add silicate cement clinker, anhydrite, granulated blast furnace slag finely ground in Step 1, and coral powder with surface adsorbed amino alcohols to a mixing mill according to the weight proportions, and mix and grind twice until the specific surface area is ≥340m². 2 / kg, producing finished cement for islands and reefs. The setting time and strength test results of the mortar specimens after mixing and curing with fresh water are shown in Table 1.

[0086] Example 26

[0087] This embodiment provides an island reef cement, composed of the following parts by weight: 72 parts silicate cement clinker (same as in Example 1), 8 parts anhydrite, 10 parts granulated blast furnace slag, and 10 parts coral powder with surface adsorption of amino alcohols (9 parts coral powder are mixed with 1 part amino alcohol grinding aid, the amino alcohol grinding aid is the same as in Example 2). Its preparation process includes the following steps: Step 1, crushing the coral reef sand, mixing it with the amino alcohol grinding aid, and performing initial grinding until the specific surface area is ≥430 m². 2 / kg, while granulated blast furnace slag is first crushed and ground to a specific surface area ≥430m². 2 / kg; Step 2: Add silicate cement clinker, anhydrite, granulated blast furnace slag finely ground in Step 1, and coral powder with surface adsorbed amino alcohols to a mixing mill according to the weight proportions, and mix and grind twice until the specific surface area is ≥320m². 2 / kg, producing finished cement for islands and reefs. The setting time and strength test results of the mortar specimens after mixing and curing with fresh water are shown in Table 1.

[0088] Example 27

[0089] This embodiment provides an island and reef cement, composed of the following parts by weight: 64 parts silicate cement clinker (same as in Example 1), 6 parts anhydrite, 20 parts granulated blast furnace slag, and 10 parts coral powder with surface adsorption of amino alcohols (9.5 parts coral powder and 0.5 parts amino alcohol grinding aid are mixed and ground together; the amino alcohol grinding aid is the same as in Example 3). Its preparation process includes the following steps:

[0090] Step 1: Crush the coral reef sand, mix it with an amino alcohol grinding aid, and perform initial grinding until the specific surface area is ≥380m². 2 / kg, while granulated blast furnace slag is first crushed and ground to a specific surface area ≥380m². 2 / kg; Step 2: Add silicate cement clinker, anhydrite, granulated blast furnace slag finely ground in Step 1, and coral powder with surface adsorbed amino alcohols to a mixing mill according to the weight proportions, and mix and grind twice until the specific surface area is ≥400m². 2 / kg, producing finished cement for islands and reefs. The setting time and strength test results of the mortar specimens after mixing and curing with fresh water are shown in Table 1.

[0091] Example 28

[0092] This embodiment provides an island and reef cement, composed of the following parts by weight: 55 parts silicate cement clinker (same as in Example 1), 5 parts anhydrite, 30 parts granulated blast furnace slag, and 10 parts coral powder with surface-adsorbed amino alcohols (9.5 parts coral powder and 0.5 parts amino alcohol grinding aid are mixed and ground together; the amino alcohol grinding aid is the same as in Example 4). Its preparation process includes the following steps:

[0093] Step 1: Crush the coral reef sand, mix it with an amino alcohol grinding aid, and perform initial grinding until the specific surface area is ≥450m². 2 / kg, while granulated blast furnace slag is first crushed and ground to a specific surface area ≥385m². 2 / kg; Step 2: Add silicate cement clinker, anhydrite, granulated blast furnace slag finely ground in Step 1, and coral powder with surface adsorbed amino alcohols to a mixing mill according to the weight proportions, and mix and grind twice until the specific surface area is ≥380m². 2 / kg, producing finished cement for islands and reefs. The setting time and strength test results of the mortar specimens after mixing and curing with fresh water are shown in Table 1.

[0094] Example 29

[0095] This embodiment provides an island reef cement, composed of the following parts by weight: 72 parts silicate cement clinker (same as in Example 1), 8 parts anhydrite, 5 parts granulated blast furnace slag, and 15 parts coral powder with surface-adsorbed amino alcohols (14 parts coral powder are mixed and ground with 1 part amino alcohol grinding aid, the amino alcohol grinding aid is the same as in Example 5). Its preparation process includes the following steps: Step 1: Crush the coral reef sand, mix with the amino alcohol grinding aid, and perform initial grinding until the specific surface area is ≥420 m². 2 / kg, while granulated blast furnace slag is first crushed and ground to a specific surface area ≥390m². 2 / kg; Step 2: Add silicate cement clinker, anhydrite, granulated blast furnace slag finely ground in Step 1, and coral powder with surface adsorbed amino alcohols to a mixing mill according to the weight proportions, and mix and grind twice until the specific surface area is ≥350m². 2 / kg, producing finished cement for islands and reefs. The setting time and strength test results of the mortar specimens after mixing and curing with fresh water are shown in Table 1.

[0096] Example 30

[0097] This embodiment provides an island reef cement, composed of the following parts by weight: 64 parts silicate cement clinker (same as in Example 1), 7 parts anhydrite, 10 parts granulated blast furnace slag, and 20 parts coral powder with surface-adsorbed amino alcohols (19 parts coral powder are mixed and ground with 1 part amino alcohol grinding aid, the amino alcohol grinding aid is the same as in Example 6). Its preparation process includes the following steps: Step 1: Crush the coral reef sand, mix with the amino alcohol grinding aid, and perform initial grinding until the specific surface area is ≥410 m². 2 / kg, while granulated blast furnace slag is first crushed and ground to a specific surface area ≥325m². 2 / kg; Step 2: Add silicate cement clinker, anhydrite, granulated blast furnace slag finely ground in Step 1, and coral powder with surface adsorbed amino alcohols to a mixing mill according to the weight proportions, and mix and grind twice until the specific surface area is ≥410m². 2 / kg, producing finished cement for islands and reefs. The setting time and strength test results of the mortar specimens after mixing and curing with fresh water are shown in Table 1.

[0098] Example 31

[0099] This embodiment provides an island reef cement, composed of the following parts by weight: 47 parts silicate cement clinker (same as in Example 1), 3 parts anhydrite, 30 parts granulated blast furnace slag, and 20 parts coral powder. Its preparation process includes the following steps: Step 1: Crush the coral reef sand and initially grind it to a specific surface area ≥ 400 m². 2 / kg, while granulated blast furnace slag and fly ash are first crushed and then ground separately to a specific surface area ≥400m². 2 / kg; Step 2: Add silicate cement clinker, anhydrite, and the granulated blast furnace slag, fly ash, and coral powder ground in Step 1 to a mixing mill according to the specified weight proportions, and mix and grind them a second time until the specific surface area is ≥395m². 2 / kg, producing finished cement for islands and reefs. The setting time and strength test results of mortar specimens using seawater mixing and curing are shown in Table 1.

[0100] Example 32

[0101] This embodiment provides an island reef cement, composed of the following parts by weight: 55 parts silicate cement clinker (same as in Example 1), 5 parts anhydrite, 10 parts granulated blast furnace slag, and 30 parts coral powder. Its preparation process includes the following steps: Step 1: Crush the coral reef sand and initially grind it to a specific surface area ≥ 430 m². 2 / kg, while granulated blast furnace slag and fly ash are first crushed and then ground separately to a specific surface area ≥430m². 2 / kg; Step 2: Add silicate cement clinker, anhydrite, and the finely ground granulated blast furnace slag, fly ash, and coral powder from Step 1 to a mixing mill according to the specified weight proportions, and mix and grind them twice until the specific surface area is ≥410m². 2 / kg, producing finished cement for islands and reefs. The setting time and strength test results of mortar specimens using seawater mixing and curing are shown in Table 1.

[0102] Example 33

[0103] This embodiment provides an island reef cement, composed of the following parts by weight: 45 parts silicate cement clinker (same as in Example 1), 5 parts anhydrite, 10 parts granulated blast furnace slag, and 40 parts coral powder. Its preparation process includes the following steps: Step 1: Crush the coral reef sand and initially grind it to a specific surface area ≥ 440 m². 2 / kg, while granulated blast furnace slag and fly ash are first crushed and then ground separately to a specific surface area ≥440m². 2 / kg; Step 2: Add silicate cement clinker, anhydrite, and the finely ground granulated blast furnace slag, fly ash, and coral powder from Step 1 to a mixing mill according to the specified weight proportions, and mix and grind them a second time until the specific surface area is ≥425m². 2 / kg, producing finished cement for islands and reefs. The setting time and strength test results of mortar specimens using seawater mixing and curing are shown in Table 1.

[0104] Example 34

[0105] This embodiment provides an island reef cement, composed of the following parts by weight: 73 parts silicate cement clinker (same as in Example 1), 7 parts anhydrite, 15 parts granulated blast furnace slag, and 5 parts coral powder. Its preparation process includes the following steps: Step 1: Crush the coral reef sand and initially grind it to a specific surface area ≥ 380 m². 2 / kg, while granulated blast furnace slag and fly ash are first crushed and then ground separately to a specific surface area ≥400m². 2 / kg; Step 2: Add silicate cement clinker, anhydrite, and the finely ground granulated blast furnace slag, fly ash, and coral powder from Step 1 to a mixing mill according to the specified weight proportions, and mix and grind them a second time until the specific surface area is ≥418m². 2 / kg, producing finished cement for islands and reefs. The setting time and strength test results of mortar specimens using seawater mixing and curing are shown in Table 1.

[0106] Example 35

[0107] This embodiment provides an island reef cement, composed of the following parts by weight: 50 parts silicate cement clinker (same as in Example 1), 5 parts anhydrite, 5 parts granulated blast furnace slag, and 5 parts coral powder. Its preparation process includes the following steps: Step 1: Crush the coral reef sand and initially grind it to a specific surface area ≥ 470 m². 2 / kg, while granulated blast furnace slag and fly ash are first crushed and then ground separately to a specific surface area ≥325m². 2 / kg; Step 2: Add silicate cement clinker, anhydrite, and the finely ground granulated blast furnace slag, fly ash, and coral powder from Step 1 to a mixing mill according to the specified weight proportions, and mix and grind them a second time until the specific surface area is ≥434m². 2 / kg, producing finished cement for islands and reefs. The setting time and strength test results of mortar specimens using seawater mixing and curing are shown in Table 1.

[0108] Example 36

[0109] This embodiment provides an island reef cement, composed of the following parts by weight: 55 parts silicate cement clinker (same as in Example 1), 5 parts anhydrite, 30 parts fly ash, and 10 parts coral powder. Its preparation process includes the following steps: Step 1: Crush the coral reef sand and initially grind it to a specific surface area ≥ 430 m². 2 / kg, while granulated blast furnace slag and fly ash are first crushed and then ground separately to a specific surface area ≥335m². 2 / kg; Step 2: Add silicate cement clinker, anhydrite, and the finely ground granulated blast furnace slag, fly ash, and coral powder from Step 1 to a mixing mill according to the specified weight proportions, and mix and grind them a second time until the specific surface area is ≥360m². 2 / kg, producing finished cement for islands and reefs. The setting time and strength test results of mortar specimens using seawater mixing and curing are shown in Table 1.

[0110] Example 37

[0111] This embodiment provides an island reef cement, composed of the following parts by weight: 72 parts silicate cement clinker (same as in Example 1), 8 parts anhydrite, 55 parts granulated blast furnace slag, and 10 parts coral powder with surface-adsorbed amino alcohols (9 parts coral powder are mixed with 1 part amino alcohol grinding aid, the amino alcohol grinding aid is the same as in Example 1). Its preparation process includes the following steps: Step 1: Crush the coral reef sand, mix with the amino alcohol grinding aid, and perform initial grinding until the specific surface area is ≥420 m². 2 / kg, while granulated blast furnace slag is first crushed and ground to a specific surface area ≥420m². 2 / kg; Step 2: Add silicate cement clinker, anhydrite, granulated blast furnace slag finely ground in Step 1, and coral powder with surface adsorbed amino alcohols to a mixing mill according to the weight proportions, and mix and grind twice until the specific surface area is ≥365m². 2 / kg, producing finished cement for islands and reefs. The setting time and strength test results of the mortar specimens after mixing and curing with fresh water are shown in Table 1.

[0112] Example 38

[0113] This embodiment provides an island reef cement, composed of the following parts by weight: 55 parts silicate cement clinker (same as in Example 1), 5 parts anhydrite, 25 parts fly ash, and 15 parts coral powder with surface-adsorbed amino alcohols (14 parts coral powder are mixed and ground with 1 part amino alcohol grinding aid, the amino alcohol grinding aid is the same as in Example 2). Its preparation process includes the following steps: Step 1: Crush the coral reef sand, mix with the amino alcohol grinding aid, and perform initial grinding until the specific surface area is ≥440 m². 2 / kg, while the fly ash is first crushed and ground to a specific surface area ≥440m². 2 / kg; Step 2: Add silicate cement clinker, anhydrite, and the finely ground fly ash and surface-adsorbed amino alcohol coral powder to a mixing mill according to the weight proportions, and mix and grind twice until the specific surface area is ≥420m². 2 / kg, producing finished cement for islands and reefs. The setting time and strength test results of the mortar specimens after mixing and curing with fresh water are shown in Table 1.

[0114] Example 39

[0115] This embodiment provides an island reef cement, composed of the following parts by weight: 64 parts silicate cement clinker (same as in Example 1), 6 parts anhydrite, 10 parts fly ash, and 20 parts coral powder with surface-adsorbed amino alcohols (19 parts coral powder are mixed and ground with 1 part amino alcohol grinding aid, the amino alcohol grinding aid is the same as in Example 3). Its preparation process includes the following steps: Step 1: Crush the coral reef sand, mix with the amino alcohol grinding aid, and perform initial grinding until the specific surface area is ≥395 m². 2 / kg, while the fly ash is first crushed and ground to a specific surface area ≥395m². 2 / kg; Step 2: Add silicate cement clinker, anhydrite, and the finely ground fly ash and surface-adsorbed amino alcohol coral powder to a mixing mill according to the weight proportions, and mix and grind twice until the specific surface area is ≥460m². 2 / kg, producing finished cement for islands and reefs. The setting time and strength test results of the mortar specimens after mixing and curing with fresh water are shown in Table 1.

[0116] Example 40

[0117] This embodiment provides an island reef cement, composed of the following parts by weight: 55 parts silicate cement clinker (same as in Example 1), 5 parts anhydrite, 20 parts fly ash, and 20 parts coral powder with surface-adsorbed amino alcohols (19 parts coral powder are mixed and ground with 1 part amino alcohol grinding aid, the amino alcohol grinding aid is the same as in Example 4). Its preparation process includes the following steps: Step 1: Crush the coral reef sand, mix with the amino alcohol grinding aid, and perform initial grinding until the specific surface area is ≥470 m². 2 / kg, while the fly ash is first crushed and ground to a specific surface area ≥345m². 2 / kg; Step 2: Add silicate cement clinker, anhydrite, and the finely ground fly ash and surface-adsorbed amino alcohol coral powder to a mixing mill according to the weight proportions, and mix and grind twice until the specific surface area is ≥394m². 2 / kg, producing finished cement for islands and reefs. The setting time and strength test results of the mortar specimens after mixing and curing with fresh water are shown in Table 1.

[0118] Example 41

[0119] This embodiment provides an island reef cement, composed of the following parts by weight: 55 parts silicate cement clinker (same as in Example 1), 5 parts anhydrite, 10 parts fly ash, and 30 parts coral powder with surface-adsorbed amino alcohols (29 parts coral powder are mixed and ground with 1 part amino alcohol grinding aid, the amino alcohol grinding aid is the same as in Example 5). Its preparation process includes the following steps: Step 1: Crush the coral reef sand, mix with the amino alcohol grinding aid, and perform initial grinding until the specific surface area is ≥350 m². 2 / kg, while the fly ash is first crushed and ground to a specific surface area ≥335m². 2 / kg; Step 2: Add silicate cement clinker, anhydrite, and the finely ground fly ash and surface-adsorbed amino alcohol coral powder to a mixing mill according to the weight proportions, and mix and grind twice until the specific surface area is ≥433m². 2 / kg, producing finished cement for islands and reefs. The setting time and strength test results of the mortar specimens after mixing and curing with fresh water are shown in Table 1.

[0120] Example 42

[0121] This embodiment provides an island reef cement, composed of the following parts by weight: 50 parts silicate cement clinker (same as in Example 1), 5 parts anhydrite, 5 parts fly ash, and 40 parts coral powder with surface-adsorbed amino alcohols (38 parts coral powder are mixed and ground with 2 parts amino alcohol grinding aid, the amino alcohol grinding aid is the same as in Example 6). Its preparation process includes the following steps: Step 1: Crush the coral reef sand, mix with the amino alcohol grinding aid, and perform initial grinding until the specific surface area is ≥365 m². 2 / kg, while the fly ash is first crushed and ground to a specific surface area ≥405m². 2 / kg; Step 2: Add silicate cement clinker, anhydrite, and the finely ground fly ash and surface-adsorbed amino alcohol coral powder to a mixing mill according to the weight proportions, and mix and grind twice until the specific surface area is ≥330m². 2 / kg, producing finished cement for islands and reefs. The setting time and strength test results of the mortar specimens after mixing and curing with fresh water are shown in Table 1.

[0122] Table 1 Test performance of cement concrete for island reefs in various embodiments and comparative examples

[0123]

[0124]

[0125] As can be seen from the performance data of the island and reef cement in Examples 1-42, the product quality of this invention is stable. It not only fully meets the technical requirements of strength grades 32.5 and 42.5 in GB / T 31289-2014 "Marine Silicate Cement," but its technical indicators even surpass those of the standard. The superiority of this invention over GB / T 31289-2014 "Marine Silicate Cement" is specifically reflected in the fact that it does not produce a 32.5L strength grade product with low early strength, and it can also produce early-strength island and reef cements such as 32.5R and 42.5R, which exceed the technical requirements of GB / T 31289-2014 "Marine Silicate Cement." Furthermore, it can also produce island and reef cements with even higher strength grades, such as 52.5 and 52.5R. In addition, the most prominent advantage of the island and reef cement of this invention is that it can be mixed and cured using both fresh water and seawater when preparing mortar and concrete.

[0126] The test results from Example 1 and Comparative Example 1-1, as well as Example 19 and Comparative Example 19-1, show that coral powder produces semi-carbon hydrated calcium aluminate, monocarbon hydrated calcium aluminate, and tricarbon hydrated calcium aluminate, which can exist stably together with ettringite (AFt), thus accelerating the early hydration of cement and promoting early strength. A comparison of the test results from Example 1 and Comparative Example 1-2 in Table 1 shows that, due to the excellent adsorption properties of the microporous structure of coral powder, the rust-inhibiting amino alcohol, as a grinding aid, has a better rust-inhibiting effect when mixed with coral powder than when the rust-inhibiting grinding aid is directly added to concrete. Therefore, compared with directly adding amino alcohol rust inhibitors during concrete mixing, the corrosion resistance effect is better when coral powder adsorbs amino alcohols and is then mixed with other components.

[0127] The structural morphology of coral powder is as follows Figure 3 As shown in the figure, the morphology of coral powder exhibits excellent adsorption properties and can effectively adsorb amino alcohols.

[0128] The 28-day hydration products of island and reef cement paste in Examples 26, 27, 30, and 35 are as follows: Figure 4 As shown, from Figure 4 It can be seen that the addition of coral powder promotes the rapid hardening and early strength of the phase. Scanning electron micrographs of island and reef cement at different ages in Examples 28 and 31 are shown below. Figure 5 As shown in the figure, the fast-hardening, early-strength phase can be seen.

[0129] Steel reinforcement corrosion current density tests were conducted on the island and reef cement-mixed concrete of Example 1 and Comparative Examples 1-3 (concrete mix proportions: 800 kg of island and reef cement, 224 kg of water, 860 kg of fine aggregate, and 369 kg of coarse aggregate per cubic meter of concrete). The results are as follows: Figure 6 As shown. From Figure 6It can be seen that the coral powder with amino alcohol adsorbed on the surface exhibits excellent rust-inhibiting effect.

[0130] This invention employs a composite technology of active mineral admixtures consisting of fly ash, finely ground slag powder, and finely ground coral powder, and utilizes the excellent adsorption properties of finely ground coral powder to "load" the grinding aid. Based on traditional island and reef cement, it adds coral powder, which can be sourced locally from offshore islands and reefs and promotes early hydration and strength growth of cement, as well as amino alcohol-based grinding aids that can protect reinforcing steel from corrosion over a long period. This achieves the goal of solving the most serious and common corrosion problems of marine environments, such as dissolution, corrosion, and chlorine-induced steel corrosion of cement concrete, while ensuring the density, impermeability, and corrosion resistance of marine concrete. It allows for the use of both fresh and seawater for mixing and curing concrete, while significantly reducing the transportation costs of construction materials to meet the needs of marine engineering construction.

[0131] In this invention, unless otherwise stated, scientific and technical terms used herein have the meanings commonly understood by those skilled in the art. Furthermore, the reagents, materials, and procedures used herein are all widely used in the relevant fields.

[0132] Finally, it should be noted that the above descriptions are merely preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A type of cement for islands and reefs, characterized in that: The island and reef cement is composed of the following components in parts by weight: Silicate cement clinker: 30~80; Active mineral admixtures: 15~65; Plaster: 2.5~6; The active mineral admixture comprises granulated blast furnace slag, fly ash, and coral powder with surface adsorption of amino alcohols, wherein the mass ratio of granulated blast furnace slag, fly ash, and coral powder with surface adsorption of amino alcohols is 5~55:5~35:5~40; or, the active mineral admixture comprises granulated blast furnace slag and coral powder with surface adsorption of amino alcohols, wherein the mass ratio of granulated blast furnace slag and coral powder with surface adsorption of amino alcohols is 5~55:5~40; or, the active mineral admixture comprises fly ash and coral powder with surface adsorption of amino alcohols, wherein the mass ratio of fly ash and coral powder with surface adsorption of amino alcohols is 5~35:5~40. The coral powder with surface adsorption of amino alcohols is obtained by mixing and grinding coral reef sand with an amino alcohol grinding aid. The amino alcohol grinding aid is triethylalanine, dimethylalanine, or a mixture of triethylalanine and dimethylalanine in a mass ratio of 1~5:1~5; The preparation process of the island and reef cement includes the following steps: Step 1: Mix crushed coral reef sand with an amino alcohol-based grinding aid, allowing the amino alcohol to be adsorbed onto the surface of the coral powder. Continue mixing until the specific surface area of ​​the coral powder with adsorbed amino alcohol is not less than 300 m². 2 / kg; Granulated blast furnace slag and / or fly ash are first crushed and then ground separately to a specific surface area of ​​not less than 300 m². 2 / kg; Step 2: Add silicate cement clinker, gypsum, and the finely ground active mineral admixtures from Step 1 to a mixing mill according to the specified weight proportions, and then mix and grind them a second time until the specific surface area is not less than 310 m². 2 / kg, producing finished cement products for islands and reefs.

2. The island and reef cement according to claim 1, characterized in that: in, The mass ratio of the coral reef sand to the amino alcohol grinding aid is 5~40:0.5~2.

3. The island and reef cement according to claim 1, characterized in that: in, The silicate cement clinker includes tricalcium silicate, dicalcium silicate, tricalcium aluminate, and tetracalcium aluminoferrite. The mass ratio of tricalcium silicate, dicalcium silicate, tricalcium aluminate, and tetracalcium aluminoferrite is 36~70:15~37:7~15:10~18.

4. The island and reef cement according to claim 1, characterized in that: in, The granulated blast furnace slag is grade S95 or higher.

5. The island and reef cement according to claim 1, characterized in that: in, The fly ash is classified as Grade II or above.

6. The island and reef cement according to claim 1, characterized in that: in, The specific surface area of ​​the granulated blast furnace slag, fly ash, and coral powder with surface adsorbed amino alcohols after fine grinding is not less than 350 m². 2 / kg.

7. The method for applying island and reef cement as described in any one of claims 1-6, characterized in that: When the island and reef cement is mixed with sand or coral reef sand to prepare mortar or concrete, fresh water is used for mixing and curing, or seawater is used for mixing and curing. Mortar or concrete mixed and cured with fresh water is used in reinforced concrete structures; Mortar or concrete mixed and cured with seawater is used for plain concrete structures.

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