Reinforced coral aggregate as well as preparation method and application thereof
Through the combination of vacuum treatment and quantum dot reinforcement, the problems of light, porous and low strength of coral aggregates are solved, which improves its application performance in island and reef engineering, and reduces transportation costs and engineering costs.
Patent Information
- Application Number
- CN202510540176.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-04-27
- Publication Date
- 2025-07-22
AI Technical Summary
Coral aggregates are light in texture, porous and low in strength, resulting in limited application in island and reef projects, which cannot meet the demand for concrete materials in island and reef construction.
By mixing the coarse coral aggregate with cement mortar and vacuum treatment, the internal pores of the coral aggregate are filled with cement mortar and adding quantum dot reinforcer to improve the density and strength of the aggregate.
It enhances the density and strength of coral aggregates, reduces porosity, and improves the interface bonding between the aggregate and the matrix. It is suitable for various structures such as buildings, bridges and breakwaters on ocean islands and reefs, reduces the transportation volume of ocean islands and reefs, and reduces engineering costs.
Smart Images
Figure CN120349136A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of concrete, and particularly relates to a reinforced coral aggregate, a preparation method thereof, and an application thereof. Background Art
[0002] In recent years, the development of marine resources has received increasing attention, and the construction of marine projects such as ports, seawalls, coastal protection, and airports on remote oceanic islands and reefs has developed particularly rapidly. As the most commonly used engineering material, concrete is a key factor determining the speed and quality of island and reef engineering construction. However, in the South China Sea islands and reefs, sand and gravel and fresh water resources are scarce, which cannot meet the demand for concrete materials in large-scale island and reef engineering construction. At the same time, the islands and reefs are far from the mainland. Adopting the resource supply method of transporting engineering materials such as sand and gravel from the mainland will greatly increase the project cost and reduce the construction efficiency. Moreover, affected by uncontrollable factors such as sea waves, the project progress cannot be effectively guaranteed.
[0003] However, it has been found in research that in the tropical and subtropical waters between the earth's tropics of cancer and capricorn, there are a large number of coral islands and coral reefs composed of coral reef rocks. As a kind of rock, the main mineral components of coral stones are aragonite and high-magnesium calcite, and the internal CaCO3 content is above 96%, which can be used as an alternative to sand and gravel. However, compared with ordinary sand and gravel aggregates, coral stone aggregates are light in weight, porous, and low in strength. They are natural light aggregates with sharp edges and corners, and coral concrete also belongs to a kind of light aggregate concrete. Experimental studies have shown that coral concrete has mechanical property defects such as high brittleness and low strength similar to other light aggregate concretes, which have extremely adverse negative effects on island and reef engineering construction and limit the application of coral aggregates in island and reef engineering. Therefore, there is an urgent need to develop a reinforced coral aggregate with better mechanical properties and durability to solve the above problems. Summary of the Invention
[0004] The purpose of the present invention is to solve the problems of poor mechanical properties and low durability of the aggregates in the coral concrete used in current island and reef engineering construction, and to provide a reinforced coral aggregate, a preparation method thereof, and an application thereof. Through a vacuum technology, the internal pores of the coral aggregate are filled with cement mortar. The coral aggregate prepared by this method has the characteristics of low porosity, high density, and high strength, and solves the defect that the coral aggregate is difficult to be used in island and reef engineering due to its light weight, porosity, and low strength.
[0005] In order to achieve the above purpose, the present invention adopts the following technical solutions:
[0006] (1) The present invention provides a reinforced coral aggregate, which is prepared by mixing coral coarse aggregate with cement mortar and then performing vacuum treatment; the cement mortar includes cement, water reducer, sand, and mineral admixture.
[0007] Further, in the cement mortar, the weight ratio of cement, water reducer, sand, mineral admixture and water is 100: 0-8: 80-120: 10-155: 26-80.
[0008] Further, the cement mortar further comprises a quantum dot enhancer; in the cement mortar, the weight ratio of cement, water reducer, sand, mineral admixture, quantum dot enhancer and water is 100: 0-8: 80-120: 10-155: 1-7: 80.
[0009] Further, the quantum dot enhancer comprises ZnS quantum dots, a dispersant, a coupling agent and a curing agent, and the weight ratio of ZnS quantum dots, dispersant, coupling agent, curing agent and water is 15-25: 6-10: 1-5: 3-8: 50-70.
[0010] Further, in the quantum dot enhancer, the weight ratio of ZnS quantum dots, dispersant, coupling agent, curing agent and deionized water is 18-22: 8-10: 2-3: 4-5: 60-70.
[0011] Further, in the quantum dot enhancer, the weight ratio of ZnS quantum dots, dispersant, coupling agent, curing agent and deionized water is 20: 8: 2: 4: 66.
[0012] Further, the mineral admixture comprises granulated blast furnace slag, fly ash, silica fume and coral powder, and the weight ratio of granulated blast furnace slag, fly ash, silica fume and coral powder is 5-55: 5-25: 0-35: 0-40.
[0013] Further, the mixing weight ratio of the coral coarse aggregate and the cement mortar is 1: 1-5, and further preferably 1: 2-5.
[0014] Further, the dispersant is polyethylene glycol, the coupling agent is silane coupling agent KH-550, and the curing agent is epoxy resin.
[0015] Further, the cement is Portland cement (ordinary Portland cement or composite Portland cement), the coral powder is ground from coral reef sand; the sand is coral sand, sea sand or river sand; the water reducer is polycarboxylate water reducer, melamine water reducer, lignosulfonate water reducer or naphthalene series water reducer.
[0016] Further, the coral coarse aggregate is made by crushing coral reefs, staghorn corals or rod-shaped corals.
[0017] Further, the fly ash is of grade II or above.
[0018] (2) The present invention also provides a method for preparing enhanced coral aggregates, comprising: preparing a quantum dot enhancer; mixing cement, a water reducer, sand, a mineral admixture, and the quantum dot enhancer, and adding water to prepare cement mortar; mixing the cement mortar and coral coarse aggregates evenly, subjecting the mixture to vacuum treatment, after the vacuum treatment, washing and sieving the initially set mixture, and obtaining the enhanced coral aggregates after sun drying and curing. The water for washing the aggregates can be recycled and reused.
[0019] Further, the method for preparing the quantum dot enhancer is: mixing zinc sulfate, thioacetamide, and tea polyphenols, and heating and reacting to obtain ZnS quantum dots; mixing the ZnS quantum dots with a dispersant, a coupling agent, a curing agent, and water, and performing ultrasonic treatment to obtain the quantum dot enhancer.
[0020] Further, the weight ratio of zinc sulfate, thioacetamide, and tea polyphenols is 30-40:50-60:12-25; the reaction temperature is 80-110°C, and the reaction time is 1-3 h.
[0021] Further, the weight ratio of zinc sulfate, thioacetamide, and tea polyphenols is 37:55:18; the reaction temperature is 90°C, and the reaction time is 2 h.
[0022] Further, the degree of vacuum for the vacuum treatment is not less than 0.9 bar.
[0023] (3) The present invention also provides the application of the above-mentioned enhanced coral aggregates in the preparation of coral concrete. The application method is: mixing the enhanced coral aggregates with cement, sand, and a mineral admixture, adding fresh water or seawater and stirring evenly, and then curing to obtain coral concrete.
[0024] Among them, the concrete mixed and cured with fresh water is used for reinforced concrete structures, such as buildings, bridges, etc. The concrete mixed and cured with seawater is used for plain concrete structures, such as breakwaters, roads, and wave dissipating blocks on oceanic islands and reefs, etc.
[0025] Advantageous Effects
[0026] Compared with the prior art, the technical solution of the present invention has the following advantageous effects:
[0027] (1) The solution of the present invention enhances the mechanical properties of coral aggregates through the synergistic effect of vacuum technology, combined with cement mortar filling and quantum dot enhancer (QDR), improves the interfacial bonding force between the aggregates and the matrix, and optimizes the interfacial bonding and stress transfer of the aggregate-matrix. At the same time, it can penetrate into the microporous structure of coral aggregates, reduce the porosity of the aggregates by filling voids and defects, increase the density and strength of the aggregates, and solve the defect that coral aggregates are difficult to be applied in island reef projects due to their light weight, porousness, and low strength.
[0028] (2) The raw materials of the coral coarse aggregate, coral sand and coral powder applied in the solution of the present invention can be directly obtained from the reefs to be constructed, significantly improving the localization of the raw materials, greatly reducing the transportation volume of the concrete materials for the oceanic reefs, reducing the cost of the reef engineering construction, having remarkable convenience and economic benefits, and meeting the needs of the oceanic engineering construction.
[0029] (3) By the reasonable proportion of mineral admixtures (granulated blast furnace slag, fly ash, silica fume, coral powder) and sand in the present invention, the mechanical properties and durability of the coral aggregate are significantly enhanced.
[0030] (4) The enhanced coral aggregate obtained in the present invention can be used for concrete mixing with fresh water or seawater according to requirements, and is applicable to various structures such as buildings, bridges and breakwaters on oceanic reefs, and has broad application prospects in the new construction, repair of concrete projects and military protection projects of reef engineering. Description of the Drawings
[0031] Figure 1 is the process flow chart of the preparation of the enhanced coral aggregate of the present invention;
[0032] Figure 2 is the filling effect diagram of the cement mortar on the coral aggregate in the enhanced coral aggregate prepared in Example 33 of the present invention;
[0033] Figure 3 is the filling process diagram of the mortar on the coral aggregate in the enhanced coral aggregate prepared in Example 33 of the present invention;
[0034] Figure 4 is the CT scan image of the coral aggregate and the CT scan image of the enhanced coral aggregate prepared in Example 33 of the present invention (wherein, the colored part represents the pore size distribution of different sizes);
[0035] Figure 5 is the stress-strain curve of the coral aggregate and the enhanced coral aggregate prepared in Example 33 of the present invention;
[0036] Figure 6 is the action mechanism diagram of the quantum dot enhancer in the coral aggregate. Detailed Embodiments
[0037] To make the objectives, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are some but not all of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.
[0038] Examples 1 - 30
[0039] Examples 1 - 30 provide a kind of enhanced coral aggregate, including cement mortar and coral coarse aggregate. Among them, the cement mortar includes cement (ordinary portland cement or composite portland cement), water reducer (polycarboxylate water reducer, melamine water reducer, lignosulfonate water reducer or naphthalene series water reducer), sand (coral sand, sea sand or river sand) and mineral admixture. The mineral admixture includes granulated blast furnace slag, fly ash, silica fume and coral micro powder. The components and their addition amounts are shown in Table 1.
[0040] The preparation method includes the following steps:
[0041] Step 1: Use the mechanical crushing method to crush coral reefs to obtain coral coarse aggregate.
[0042] Step 2: Mix cement, water reducer, sand, granulated blast furnace slag, fly ash, silica fume and coral micro powder with fresh water to prepare cement mortar.
[0043] Step 4: Mix the cement mortar and the coral coarse aggregate evenly, and use a vacuum pump to vacuumize the mixture (the vacuum degree of the vacuum treatment is not less than 0.9 bar) so that the cement mortar fills the internal pores of the coral aggregate. After the vacuum degree is lower than 0.9 bar and the pressure is stable, turn off the vacuum pump. After the vacuum treatment, sieve the initially set mixture, wash it with water and sieve it before final setting, and obtain the coral aggregate after sunning and curing.
[0044] Table 1: Weight parts of each component in Examples 1 - 30
[0045]
[0046]
[0047] Examples 31 - 35
[0048] Examples 31 - 35 of the present invention provide a kind of enhanced coral aggregate, including cement mortar and coral coarse aggregate. Among them, the cement mortar includes cement, water reducer, sand, mineral admixture and quantum dot enhancer. The mineral admixture includes granulated blast furnace slag, fly ash, silica fume and coral micro powder. The components and their addition amounts are shown in Table 2.
[0049] The preparation method includes the following steps:
[0050] Step 1: Use the mechanical crushing method to crush coral reefs to obtain coral coarse aggregate.
[0051] Step 2: Mix zinc sulfate, thioacetamide, and tea polyphenols in a weight ratio of 37:55:18. After mixing, heat the mixture to 90 °C and react for 2 h to obtain ZnS quantum dots. Let the synthesized ZnS quantum dots cool to room temperature, and then rinse and filter them with deionized water to remove impurities. Mix the impurity-removed ZnS quantum dots with polyethylene glycol, silane coupling agent KH-550, epoxy resin, and deionized water, and perform ultrasonic treatment to obtain a quantum dot enhancer.
[0052] Step 3: Mix cement, water reducer, sand, granulated blast furnace slag, fly ash, silica fume, coral micro powder, and the quantum dot enhancer, and add fresh water to stir and prepare cement mortar.
[0053] Step 4: After uniformly mixing the cement mortar with coral coarse aggregate, use a vacuum pump to subject the mixture to vacuum treatment (the vacuum degree of the vacuum treatment is not less than 0.9 bar) so that the cement mortar fills the internal pores of the coral aggregate. After the vacuum degree is lower than 0.9 bar and the pressure is stable, turn off the vacuum pump. After vacuum treatment, sieve the initially set mixture, wash it with water and sieve it before final setting, and then dry and cure it to obtain enhanced coral aggregate. The water for washing the aggregate can be recycled and reused.
[0054] Table 2: Weight parts of each component in Examples 31 - 35
[0055]
[0056] Comparative Example 1
[0057] Comparative Example 1 is coral reef coarse aggregate, which is prepared by crushing coral reefs through a mechanical crushing method.
[0058] Application Example 1
[0059] This application example provides a coral concrete, which is composed of the following formula in weight parts: 100 parts of ordinary Portland cement, 55 parts of granulated blast furnace slag, 27 parts of fly ash, 873 parts of coral sand, 55 parts of water, and 211 parts of coral coarse aggregate (coral reef prepared in Comparative Example 1).
[0060] Its preparation process includes the following steps: First, put the coral coarse aggregate into a forced mixer and dry mix for 1 min, then pour in a fixed amount of water and mix for 3 min to complete the pre-absorption process of the coral aggregate. Then, add coral sand and cementitious materials (cement, fly ash, and slag) and mix evenly, and then add the remaining water and mix for 3 min. Next, pour the concrete mixture onto a steel plate platform for slump test. Finally, use a shovel to remix the concrete mixture on the steel plate, and then pour it into a mold coated with a release agent and vibrate it into shape, and cure it for 28 d.
[0061] Application Example 2
[0062] This application example provides a kind of coral concrete, which is composed of the following formula in parts by weight: 100 parts of ordinary Portland cement, 55 parts of granulated blast furnace slag, 27 parts of fly ash, 873 parts of coral sand, 52 parts of water, and 220 parts of coral coarse aggregate (the enhanced coral aggregate prepared in Example 3).
[0063] Its preparation process includes the following steps: First, put the enhanced coral aggregate, cementitious materials (cement, fly ash and slag) and coral sand into a forced mixer and mix evenly, then pour in water and mix for 3 min. Next, pour the concrete mixture onto a steel plate platform for slump test. Finally, use a shovel to remix the concrete mixture on the steel plate, then pour it into a mold coated with release agent and vibrate it into shape. Cure for 28 d.
[0064] Application Example 3
[0065] This application example provides a kind of coral concrete, which is composed of the following formula in parts by weight: 100 parts of ordinary Portland cement, 9 parts of granulated blast furnace slag, 19 parts of fly ash, 139 parts of coral sand, 36 parts of water, and 139 parts of coral coarse aggregate (the coral reef prepared in Comparative Example 1).
[0066] Its preparation process includes the following steps: First, put the coral coarse aggregate into a forced mixer and dry mix for 1 min, then pour in a certain amount of water and mix for 3 min to complete the pre-absorption process of the coral aggregate. Then, add the cementitious materials (cement, fly ash and slag) and coral sand and mix evenly, and then add the remaining water and mix for 3 min. Next, pour the concrete mixture onto a steel plate platform for slump test. Finally, use a shovel to remix the concrete mixture on the steel plate, then pour it into a mold coated with release agent and vibrate it into shape. Cure for 28 d.
[0067] Application Example 4
[0068] This application example provides a kind of coral concrete, which is composed of the following formula in parts by weight: 100 parts of ordinary Portland cement, 8 parts of granulated blast furnace slag, 19 parts of fly ash, 138 parts of coral sand, 35 parts of water, and 142 parts of coral coarse aggregate (the enhanced coral aggregate prepared in Example 3).
[0069] Its preparation process includes the following steps: First, put the enhanced coral aggregate, cementitious materials (cement, fly ash and slag) and coral sand into a forced mixer and mix evenly, then pour in water and mix for 3 min. Next, pour the concrete mixture onto a steel plate platform for slump test. Finally, use a shovel to remix the concrete mixture on the steel plate, then pour it into a mold coated with release agent and vibrate it into shape. Cure for 28 d.
[0070] Application Example 5
[0071] This application example provides a kind of coral concrete, which is composed of the following formula in parts by weight: 100 parts of ordinary Portland cement, 8 parts of granulated blast furnace slag, 19 parts of fly ash, 138 parts of coral sand, 35 parts of water, and 143 parts of coral coarse aggregate (the enhanced coral aggregate prepared in Example 33).
[0072] Its preparation process includes the following steps: First, put the enhanced coral aggregate, cementitious materials (cement, fly ash and slag) and coral sand into a forced mixer and mix evenly, then pour in water and mix for 3 minutes. Next, pour the concrete mixture onto a steel plate platform for slump test. Finally, use a shovel to remix the concrete mixture on the steel plate, and then pour it into a mold that has been coated with mold release agent and vibrate it into shape. Cure for 28 days.
[0073] Effect verification:
[0074] 1. Conduct performance tests on the coral aggregates prepared in Examples 1 to 35 and Comparative Example 1.
[0075] The test parameters are: apparent density, porosity, uniaxial compression peak stress and compression toughness index.
[0076] The test results are shown in Table 3.
[0077] 2. Conduct performance tests on the coral concretes prepared in Application Examples 1 to 5.
[0078] The test parameters are: 28-day compressive strength and concrete strength grade.
[0079] The test results are shown in Table 4.
[0080] Table 3: Performance test results of coral aggregates in Examples 1 to 35 and Comparative Example 1
[0081]
[0082]
[0083] As can be seen from Table 3, compared with Comparative Example 1, after enhancing the coral coarse aggregate using the method of the present invention, parameters such as its apparent density, porosity, uniaxial compression peak stress, compression toughness index, and crushing index are all improved. After introducing the quantum dot enhancer (Examples 31 - 35), the porosity of the aggregate is reduced to 2.08% - 3.14%, the uniaxial compression peak stress is increased to 20.19 - 24.13 MPa, and the compression toughness index is up to 10.35 at most, which is significantly better than the scheme without adding the quantum dot enhancer (such as Example 1). QDR forms stable chemical bonds by chemically reacting with the minerals on the surface of the coral aggregate, thereby enhancing the interfacial bonding force between the aggregate and the matrix and optimizing the interfacial bonding and stress transfer between the aggregate and the matrix. At the same time, it can penetrate into the microporous structure of the coral aggregate, and by filling voids and defects, improve the density and strength of the aggregate.
[0084] Table 4: Test Results of the Performance of Coral Concrete in Application Examples 1 - 5
[0085]
[0086] As can be seen from Table 4, compared with Comparative Example 1, when preparing coral concrete using the enhanced coral coarse aggregate of the present invention, the compressive strength is increased by 125% compared with the original aggregate (comparative example), and the strength grade is improved (C35 → C85). Moreover, the coral concrete prepared by introducing the quantum dot - enhanced coral coarse aggregate (Application Example 5) is significantly better than the scheme without adding the quantum dot enhancer (Application Example 4), verifying the significant advantages of QDR in engineering applications.
[0087] In reef engineering, ZnS quantum dots (1 - 10 nm) can penetrate into the porous structure of coral aggregates (the pore size is usually in the micron range), partially fill the pores, reduce the water absorption rate of the aggregates, and improve the density. Its high specific surface area and surface activity can improve the interfacial transition zone (ITZ) between the coral aggregate and the cement matrix, enhance mechanical interlocking and chemical bonding. On the premise of low dosage, surface modification, and dispersion optimization, ZnS quantum dots can improve the density, early strength, and impermeability of coral concrete through pore filling, interfacial strengthening, and catalytic effects.
[0088] The solution of the present invention enhances the mechanical properties of coral aggregates through the synergistic action of vacuum technology combined with cement mortar filling and quantum dot enhancer (QDR), and can solve problems such as the shortage of raw materials, excessive project cost, and long construction period in reef engineering. It can greatly reduce the transportation volume of building raw materials for ocean reef engineering, and has significant convenience and economic benefits. In addition, the production process of the product of the present invention is simple, and it is applicable to reef engineering such as dams, ports, roads, and airport runways, and has a wide application prospect in the new construction, repair of concrete projects, and military protection projects of reef engineering.
[0089] As described above, it is only the specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by those skilled in the art within the technical scope disclosed by the present invention should be covered within the protection scope of the present invention.
Claims
1. An enhanced coral aggregate, characterized in that the enhanced coral aggregate is made by mixing coral coarse aggregate with cement mortar and then subjecting it to vacuum treatment; the cement mortar includes cement, water reducer, sand and mineral admixture.
2. The enhanced coral aggregate according to claim 1, characterized in that the cement mortar further includes a quantum dot enhancer; in the cement mortar, the weight ratio of cement, water reducer, sand, mineral admixture and quantum dot enhancer is 100: 0-8: 80-120: 10-155: 1-7.
3. The enhanced coral aggregate according to claim 2, characterized in that the quantum dot enhancer includes ZnS quantum dots, dispersant, coupling agent and curing agent, and the weight ratio of ZnS quantum dots, dispersant, coupling agent, curing agent and water is 15-25: 6-10: 1-5: 3-8: 50-70.
4. The enhanced coral aggregate according to claim 1, characterized in that the mineral admixture includes granulated blast furnace slag, fly ash, silica fume and coral micro powder, and the weight ratio of granulated blast furnace slag, fly ash, silica fume and coral micro powder is 5-55: 5-25: 0-35: 0-40.
5. The enhanced coral aggregate according to claim 3, characterized in that the dispersant is polyethylene glycol, the coupling agent is silane coupling agent KH-550, and the curing agent is epoxy resin.
6. The enhanced coral aggregate according to claim 4, characterized in that the cement is Portland cement, the coral micro powder is ground from coral reef sand; the sand is coral sand, sea sand or river sand; the water reducer is polycarboxylate water reducer, melamine water reducer, lignosulfonate water reducer or naphthalene series water reducer; the coral coarse aggregate is made by crushing coral reef stone as raw material.
7. The preparation method of the enhanced coral aggregate according to any one of claims 1 to 6, characterized in that, Including: Preparing a quantum dot enhancer; Mixing cement, water reducer, sand, mineral admixture and quantum dot enhancer, and adding water to prepare cement mortar; Mixing the cement mortar with the coral coarse aggregate and stirring evenly, subjecting the mixture to vacuum treatment, after vacuum treatment, washing and sieving the initially set mixture, and obtaining the enhanced coral aggregate after sunning and curing.
8. The preparation method of the enhanced coral aggregate according to claim 7, characterized in that the preparation method of the quantum dot enhancer is: Mixing zinc sulfate, thioacetamide and tea polyphenols, heating and reacting to obtain ZnS quantum dots; Mixing the ZnS quantum dots with a dispersant, a coupling agent, a curing agent and water, and performing ultrasonic treatment to obtain a quantum dot enhancer.
9. The preparation method of the enhanced coral aggregate according to claim 8, characterized in that the weight ratio of zinc sulfate, thioacetamide and tea polyphenols is 30-40: 50-60: 12-25; the reaction temperature is 80-110 °C, and the reaction time is 1-3 h.
10. The application of the enhanced coral aggregate according to any one of claims 1-6 in the preparation of coral concrete, and the application method is: Mixing the enhanced coral aggregate with cement, sand and mineral admixture, adding fresh water or seawater and stirring evenly, and then curing to obtain coral concrete.