Conductive concrete with gold tailings sand as full aggregate and preparation method thereof
By using gold tailings sand as the whole aggregate, combined with ultrasonic dispersion and surface modification treatment of zero-dimensional and one-dimensional conductive fillers, the problem of uneven conductivity of traditional conductive concrete was solved, achieving uniform conductivity and environmental friendliness and economy.
Patent Information
- Application Number
- CN202610449793.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-04-08
- Publication Date
- 2026-06-26
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Abstract
Description
Technical Field
[0001] This invention relates to the field of building materials, and in particular to a conductive concrete using gold tailings sand as the sole aggregate and its preparation method. Background Technology
[0002] In the field of construction engineering, concrete is widely used due to its excellent mechanical properties and durability. With the development of technologies such as intelligent buildings, environmental monitoring, and electromagnetic shielding, the single structural function of traditional concrete is gradually failing to meet the needs. Conductive concrete, due to its combination of conductivity and load-bearing capacity, has become a research hotspot for the next generation of intelligent building materials.
[0003] Currently, conductive concrete is usually prepared by incorporating conductive fillers such as carbon fiber, graphite, graphene or metal oxides into a cement matrix as functional components. However, the preparation of traditional conductive concrete has the following main problems: (1) The particle size of conventional concrete aggregates (such as crushed stone, sand, etc.) differs greatly from that of conductive fillers, which can easily lead to uneven dispersion of the conductive phase in the matrix, forming local agglomeration and affecting the uniformity of conductivity; (2) The conductive network of a single conductive filler (such as using only carbon fiber or graphite) has anisotropy, which makes the conductivity of concrete vary significantly in different directions, which is not conducive to practical engineering applications; (3) To achieve a lower resistivity, a large amount of conductive filler is often required, which not only increases the cost but may also reduce the mechanical strength of the concrete.
[0004] In addition, some studies have attempted to use gold tailings sand from mining solid waste as a substitute for traditional aggregates in order to achieve resource utilization. However, the excessively fine particles of gold tailings sand result in excessively high internal porosity, with the lowest porosity currently still as high as 46.4%, which fails to meet the requirement of no more than 44% porosity in aggregates as stipulated in "Construction Sand" (GB / T 14684-2022). This makes it difficult to directly apply to conventional building materials and limits its further application in the field of conductive concrete. Summary of the Invention
[0005] This invention provides a conductive concrete using gold tailings sand as the main aggregate and its preparation method, in order to solve the problem of poor conductivity and excessive differences in conductivity in different directions in traditional conductive concrete.
[0006] To solve the above-mentioned technical problems, the present invention provides the following technical solution: This invention provides a conductive concrete using gold tailings sand as the sole aggregate, comprising the following raw materials in parts by weight: 50-200 parts of gold tailings sand, 10-15 parts of zero-dimensional conductive filler, 1-2 parts of one-dimensional conductive filler, 80 parts of inorganic cementitious material, 20 parts of fly ash, 2-4 parts of surface modifier, and 30-40 parts of water. In the gold tailings, the proportion of particles with a diameter of 0.3~0.6mm (excluding 0.6mm) is 26~28wt%, the proportion of particles with a diameter of 0.15~0.3mm (excluding 0.3mm) is 21~24wt%, the proportion of particles with a diameter of 0.075-0.15mm (excluding 0.15mm) is 19~21wt%, and the proportion of particles <0.075mm is 29~31wt%.
[0007] The conductive concrete of this invention uses gold tailings sand with a particle size of micrometers, which is currently unsuitable for building materials, and is rationally graded to replace traditional aggregates. Its smaller particle size allows for better matching with nano / micrometer-sized conductive fillers, improving the dispersion uniformity of the conductive phase and reducing agglomeration. Simultaneously, the gold tailings sand serves as a solid waste resource, offering both environmental and economic advantages. Furthermore, this invention employs a strategy of synergistic enhancement of conductivity through multi-dimensional conductive fillers: graphite particles form the basic structure of a conductive network within the cement matrix, while carbon fibers, with their high aspect ratio, construct a three-dimensional cross-linked network. The synergistic effect of these two components significantly reduces resistivity, improves conductivity uniformity, and reduces the amount of filler required. This technical solution provides a feasible approach for the engineering application of conductive concrete, making its practical applications in structural health monitoring, intelligent sensing, and other fields more promising.
[0008] In some specific embodiments, conductive concrete using gold tailings sand as the sole aggregate comprises the following raw materials in parts by weight: The composition includes 100-150 parts of gold tailings sand, 12-13 parts of zero-dimensional conductive filler, 1.5-1.8 parts of one-dimensional conductive filler, 80 parts of inorganic cementitious material, 20 parts of fly ash, 2.5-3 parts of surface modifier, and 35-38 parts of water.
[0009] In some specific embodiments, the gold tailings sand contains 27 wt% of particles with a diameter of 0.3-0.6 mm excluding 0.6 mm, 23.2 wt% of particles with a diameter of 0.15-0.3 mm excluding 0.3 mm, 19.9 wt% of particles with a diameter of 0.075-0.15 mm excluding 0.15 mm, and 29.9 wt% of particles with a diameter <0.075 mm.
[0010] In some specific embodiments, the zero-dimensional conductive filler includes graphite.
[0011] In some specific embodiments, the one-dimensional conductive material includes carbon fiber.
[0012] In some specific embodiments, the inorganic gel material includes ordinary silicate cement and / or silicate cement; The strengths of the ordinary silicate cement and the silicate cement are independently 42.5 and 52.5, respectively.
[0013] In some specific embodiments, the surface modifier includes a water-reducing agent and a defoamer.
[0014] In some specific embodiments, the mass ratio of the water-reducing agent to the defoamer is 100:(3~5).
[0015] In some specific embodiments, the water-reducing agent includes a polycarboxylate water-reducing agent.
[0016] In some specific embodiments, the defoamer includes an organosilicone defoamer.
[0017] A second aspect of the present invention also provides a method for preparing the above-mentioned conductive concrete using gold tailings sand as the main aggregate, comprising the following steps: One-dimensional conductive material is physically broken down to obtain a broken-down one-dimensional conductive material; zero-dimensional conductive material is mixed with water and subjected to a first ultrasonic dispersion to obtain an aqueous dispersion of zero-dimensional conductive material. The aqueous dispersions of the dispersed one-dimensional conductive material and the zero-dimensional conductive material are mixed, a surface modifier is added, and a second ultrasonic dispersion is performed to obtain a conductive material dispersion. Inorganic gel material, fly ash and gold tailings sand are mixed to obtain a mixed dry material; The conductive material dispersion and the dry mixture are mixed, stirred, and then poured into molds to obtain conductive concrete.
[0018] The present invention discloses a method for preparing conductive concrete, which involves using zero-dimensional and one-dimensional conductive fillers, mechanically dispersing them, and then ultrasonically treating them under the action of a surface modifier; mixing gold tailings sand as aggregate with inorganic cementitious materials to obtain a dry material; adding the ultrasonically obtained conductive material dispersion to the dry material for further dispersion, and finally obtaining conductive concrete. This invention provides a method for preparing conductive concrete using gold tailings sand as the sole aggregate and multi-dimensional conductive fillers working synergistically. By using gold tailings sand as the sole aggregate for conductive concrete and combining it with zero-dimensional and one-dimensional conductive fillers in a synergistic design, the conductivity of traditional conductive concrete can be effectively improved.
[0019] In this invention, uniform dispersion of two dimensional materials, one-dimensional conductive material and zero-dimensional conductive material, can be achieved through two ultrasonic dispersion processes.
[0020] In some specific implementations, the conditions for the first and second ultrasonic dispersions are independent: a frequency of 20-30 kHz and a time of 5-10 min.
[0021] In some specific embodiments, the mixing process in a planetary cement mortar mixer involves first mixing at a rotation speed of 120-150 r / min and a revolution speed of 50-80 r / min for 2-5 minutes, followed by standing for 3 minutes, and then mixing at a rotation speed of 270-290 r / min and a revolution speed of 110-150 r / min for 2-5 minutes.
[0022] Compared with the prior art, the present invention has the following beneficial effects: (1) This invention uses gold tailings sand as the whole aggregate of conductive concrete and combines the synergistic effect of multi-dimensional conductive fillers for proportioning design, which can produce conductive concrete with good conductivity and small difference in conductivity in all directions.
[0023] (2) The present invention uses gold tailings sand as the aggregate for conductive concrete, which reduces the mining of natural river sand in traditional conductive concrete and saves resources.
[0024] (3) In this invention, the zero-dimensional conductive filler and water were first ultrasonically dispersed, and the one-dimensional conductive filler was physically dispersed. Then, the dispersed one-dimensional conductive filler was added to the mixture of ultrasonically dispersed zero-dimensional conductive filler and water. After adding surfactant, it was ultrasonically treated again to achieve uniform dispersion of conductive fillers of different dimensions. Detailed Implementation
[0025] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments. The embodiments of this application are only examples, and all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.
[0026] Example 1 Conductive concrete using gold tailings sand as the sole aggregate is made from the following raw materials in parts by weight: The composition includes 150 parts gold tailings sand, 13 parts zero-dimensional conductive filler graphite, 1.5 parts one-dimensional conductive filler carbon fiber, 80 parts inorganic cementitious material 42.5 silicate cement, 20 parts fly ash, 3 parts surface modifier, and 35 parts water. The surfactants include a polycarboxylate superplasticizer and an organosilicon defoamer in a mass ratio of 100:3. In the gold tailings sand, particles with a diameter of 0.3~0.6mm (excluding 0.6mm) account for 27wt%, particles with a diameter of 0.15~0.3mm (excluding 0.3mm) account for 23.2wt%, particles with a diameter of 0.075-0.15mm (excluding 0.15mm) account for 19.9wt%, and particles <0.075mm account for 29.9wt%.
[0027] The preparation of conductive concrete using the aforementioned gold tailings sand as a complete aggregate includes the following steps: Place the carbon fiber into a high-speed blender and run it for 5 minutes to break it down. Graphite and water were mixed and ultrasonically dispersed at a frequency of 20 kHz for 5 min. Then, the mixture was mixed with the dispersed carbon fiber, a surface modifier was added, and ultrasonically dispersed at a frequency of 20 kHz for 5 min to obtain a conductive material dispersion. 42.5 silicate cement, fly ash and gold tailings sand are mixed and dispersed to obtain a mixed dry material; The conductive material dispersion and the dry mixture are mixed and stirred slowly for 3 minutes in a planetary cement mortar mixer at a rotation speed of 140 r / min and a revolution speed of 60 r / min. After standing for 3 minutes, the mixture is stirred rapidly for 3 minutes at a rotation speed of 285 r / min and a revolution speed of 125 r / min. The mixture is then poured into molds to obtain conductive concrete.
[0028] Example 2 Conductive concrete using gold tailings sand as the sole aggregate is made from the following raw materials in parts by weight: The composition includes 150 parts gold tailings sand, 13 parts zero-dimensional conductive filler graphite, 80 parts inorganic cementitious material 42.5 silicate cement, 20 parts fly ash, 3 parts surface modifier, and 35 parts water. The surfactants include a polycarboxylate superplasticizer and an organosilicon defoamer in a mass ratio of 100:3. In the gold tailings sand, particles with a diameter of 0.3~0.6mm (excluding 0.6mm) account for 27wt%, particles with a diameter of 0.15~0.3mm (excluding 0.3mm) account for 23.2wt%, particles with a diameter of 0.075-0.15mm (excluding 0.15mm) account for 19.9wt%, and particles <0.075mm account for 29.9wt%.
[0029] The preparation of conductive concrete using the aforementioned gold tailings sand as a complete aggregate includes the following steps: Graphite and water were mixed and ultrasonically dispersed at 20 kHz for 5 min. A surface modifier was added and ultrasonically dispersed at 20 kHz for 5 min to obtain a conductive material dispersion. 42.5 silicate cement, fly ash and gold tailings sand are mixed and dispersed to obtain a mixed dry material; The conductive material dispersion and the dry mixture are mixed and stirred slowly for 3 minutes in a planetary cement mortar mixer at a rotation speed of 140 r / min and a revolution speed of 60 r / min. After standing for 3 minutes, the mixture is stirred rapidly for 3 minutes at a rotation speed of 285 r / min and a revolution speed of 125 r / min. The mixture is then poured into molds to obtain conductive concrete.
[0030] Example 3 Conductive concrete using gold tailings sand as the sole aggregate is made from the following raw materials in parts by weight: The composition includes 150 parts gold tailings sand, 1.5 parts one-dimensional conductive filler carbon fiber, 80 parts inorganic cementitious material 42.5 silicate cement, 20 parts fly ash, 3 parts surface modifier, and 35 parts water. The surfactants include a polycarboxylate superplasticizer and an organosilicon defoamer in a mass ratio of 100:3. In the gold tailings sand, particles with a diameter of 0.3~0.6mm (excluding 0.6mm) account for 27wt%, particles with a diameter of 0.15~0.3mm (excluding 0.3mm) account for 23.2wt%, particles with a diameter of 0.075-0.15mm (excluding 0.15mm) account for 19.9wt%, and particles <0.075mm account for 29.9wt%.
[0031] The preparation of conductive concrete using the aforementioned gold tailings sand as a complete aggregate includes the following steps: The carbon fiber was placed in a high-speed blender and run for 5 minutes to break it up; then water and surfactant were added and ultrasonically dispersed at a frequency of 20 kHz for 5 minutes to obtain a conductive material dispersion. 42.5 silicate cement, fly ash and gold tailings sand are mixed and dispersed to obtain a mixed dry material; The conductive material dispersion and the dry mixture are mixed and stirred slowly for 3 minutes in a planetary cement mortar mixer at a rotation speed of 140 r / min and a revolution speed of 60 r / min. After standing for 3 minutes, the mixture is stirred rapidly for 3 minutes at a rotation speed of 285 r / min and a revolution speed of 125 r / min to obtain conductive concrete.
[0032] Example 4 Conductive concrete using manufactured sand as the sole aggregate is made from the following raw materials in parts by weight: The mixture contains 150 parts of manufactured sand (particle size <2.35mm), 13 parts of zero-dimensional conductive filler graphite, 1.5 parts of one-dimensional conductive filler carbon fiber, 80 parts of inorganic cementitious material 42.5 silicate cement, 20 parts of fly ash, 3 parts of surface modifier and 30 parts of water; wherein the surfactants include polycarboxylate superplasticizer and organosilicon defoamer with a mass ratio of 100:3.
[0033] The preparation of the above-mentioned conductive concrete with manufactured sand as a complete aggregate includes the following steps: Place the carbon fiber into a high-speed blender and run it for 5 minutes to break it down. Graphite and water were mixed and ultrasonically dispersed at a frequency of 20 kHz for 5 min. Then, the mixture was mixed with the dispersed carbon fiber, a surface modifier was added, and ultrasonically dispersed at a frequency of 20 kHz for 5 min to obtain a conductive material dispersion. 42.5 silicate cement, fly ash, and manufactured sand are mixed and dispersed to obtain a mixed dry material; The conductive material dispersion and the dry mixture are mixed and stirred slowly for 3 minutes in a planetary cement mortar mixer at a rotation speed of 140 r / min and a revolution speed of 60 r / min. After standing for 3 minutes, the mixture is stirred rapidly for 3 minutes at a rotation speed of 285 r / min and a revolution speed of 125 r / min. The mixture is then poured into molds to obtain conductive concrete.
[0034] Example 5 Conductive concrete using gold tailings sand as the sole aggregate is made from the following raw materials in parts by weight: The composition includes 150 parts gold tailings sand, 13 parts zero-dimensional conductive filler graphite, 1.5 parts one-dimensional conductive filler carbon fiber, 80 parts inorganic cementitious material 42.5 silicate cement, 20 parts fly ash, 3 parts surface modifier, and 35 parts water. The surfactants include a polycarboxylate superplasticizer and an organosilicon defoamer in a mass ratio of 100:3. In the gold tailings sand, particles with a diameter of 0.3~0.6mm (excluding 0.6mm) account for 27wt%, particles with a diameter of 0.15~0.3mm (excluding 0.3mm) account for 23.2wt%, particles with a diameter of 0.075-0.15mm (excluding 0.15mm) account for 19.9wt%, and particles <0.075mm account for 29.9wt%.
[0035] The preparation of conductive concrete using the aforementioned gold tailings sand as a complete aggregate includes the following steps: 42.5 silicate cement, fly ash, and gold tailings sand are mixed and dispersed to obtain a mixed dry material; The surface modifier is added to water and stirred evenly; then it is mixed with the dry mixture, and then carbon fiber and graphite are added. The mixture is stirred slowly for 3 minutes in a planetary cement mortar mixer at a rotation speed of 140 r / min and a revolution speed of 60 r / min, then left to stand for 3 minutes, and then stirred rapidly for 3 minutes at a rotation speed of 285 r / min and a revolution speed of 125 r / min. The mixture is then poured into molds to obtain conductive concrete.
[0036] Example 6 Conductive concrete using manufactured sand as the sole aggregate is made from the following raw materials in parts by weight: The mixture contains 150 parts of manufactured sand, 13 parts of zero-dimensional conductive filler graphite, 1.5 parts of one-dimensional conductive filler carbon fiber, 80 parts of inorganic cementitious material 42.5 silicate cement, 20 parts of fly ash, 3 parts of surface modifier and 30 parts of water; among which, the surfactants include polycarboxylate superplasticizer and organosilicon defoamer with a mass ratio of 100:3.
[0037] The preparation of the above-mentioned conductive concrete with manufactured sand as a complete aggregate includes the following steps: 42.5 silicate cement, fly ash, and manufactured sand are mixed and dispersed to obtain a mixed dry material; The surface modifier is added to water and stirred evenly; then it is mixed with the dry mixture, and then carbon fiber and graphite are added. The mixture is stirred slowly for 3 minutes in a planetary cement mortar mixer at a rotation speed of 140 r / min and a revolution speed of 60 r / min, and then left to stand for 3 minutes. Then, it is stirred rapidly for 3 minutes at a rotation speed of 285 r / min and a revolution speed of 125 r / min. The mixture is then poured into molds to obtain conductive concrete.
[0038] Performance testing The conductive concrete in Examples 1-6 was subjected to the following performance tests: (1) 3d and 7d compressive and flexural strength tests: The standard is GB / T 17671-2021 Cement Mortar Strength Test Method (ISO Method), in which the loading speed of the compressive strength test block is maintained at 2.4KN / s and the loading speed of the flexural strength test block is maintained at 50N / s.
[0039] (2) Resistivity and conductivity are calculated using the following formulas: in: resistivity R is the material resistance. A is the cross-sectional area of the material. L is the length of the material. in: conductivity resistivity In this invention, the resistance is measured using the voltmeter-ammeter method, and three tests are performed. The average of the three sets of values is taken as the resistance value.
[0040] Among them, the specimen size for mechanical performance testing is 40mm×40mm×160mm, and the specimen size for electrical performance testing is 100mm×100mm×100mm.
[0041] The test results are shown in Table 1.
[0042] Table 1 Performance test results of conductive concrete in Examples 1-6
[0043] As shown in the table above, the treatment method for the conductive filler required by this invention significantly reduces the anisotropic differences in the conductivity of conductive concrete. Similarly, replacing manufactured sand with gold tailings sand also significantly reduces the resistance of conductive concrete and lowers costs. Furthermore, since this invention primarily utilizes gold tailings sand, which is difficult to use as a building material, as a raw material, it has a large source of raw materials. Moreover, gold tailings sand occupies land and pollutes the environment; therefore, using it as a raw material in this invention has excellent environmental benefits.
[0044] Although preferred embodiments of the invention have been shown and described, it is conceivable that those skilled in the art can devise various modifications to the invention within the spirit and scope of the appended claims.
Claims
1. An electrically conductive concrete with gold tailings sand as full aggregate, characterized in that, The raw materials include the following parts by weight: 50-200 parts of gold tailings sand, 10-15 parts of zero-dimensional conductive filler, 1-2 parts of one-dimensional conductive filler, 80 parts of inorganic cementitious material, 20 parts of fly ash, 2-4 parts of surface modifier, and 30-40 parts of water. In the gold tailings, the proportion of particles with a diameter of 0.3~0.6mm (excluding 0.6mm) is 26~28wt%, the proportion of particles with a diameter of 0.15~0.3mm (excluding 0.3mm) is 21~24wt%, the proportion of particles with a diameter of 0.075-0.15mm (excluding 0.15mm) is 19~21wt%, and the proportion of particles <0.075mm is 29~31wt%.
2. The electrically conductive concrete with gold tailings sand as full aggregate according to claim 1, characterized in that, The raw materials include the following parts by weight: The composition includes 100-150 parts of gold tailings sand, 12-13 parts of zero-dimensional conductive filler, 1.5-1.8 parts of one-dimensional conductive filler, 80 parts of inorganic cementitious material, 20 parts of fly ash, 2.5-3 parts of surface modifier, and 35-38 parts of water.
3. The electrically conductive concrete with gold tailings sand as full aggregate according to claim 1, characterized in that, Of the gold tailings, 27 wt% consisted of particles with a diameter of 0.3-0.6 mm excluding 0.6 mm, 23.2 wt% consisted of particles with a diameter of 0.15-0.3 mm excluding 0.3 mm, 19.9 wt% consisted of particles with a diameter of 0.075-0.15 mm excluding 0.15 mm, and 29.9 wt% consisted of particles with a diameter <0.075 mm.
4. The electrically conductive concrete with gold tailings sand as full aggregate according to claim 1, characterized in that, The zero-dimensional conductive filler includes graphite.
5. The conductive concrete using gold tailings sand as the complete aggregate according to claim 1, characterized in that, The one-dimensional conductive material includes carbon fiber.
6. The conductive concrete using gold tailings sand as the complete aggregate according to claim 1, characterized in that, The inorganic gel material includes ordinary silicate cement and / or silicate cement; The strengths of the ordinary silicate cement and the silicate cement are independently 42.5 and 52.5, respectively.
7. The conductive concrete using gold tailings sand as the complete aggregate according to claim 1, characterized in that, The surface modifier includes a water-reducing agent and a defoamer.
8. The conductive concrete using gold tailings sand as the complete aggregate according to claim 7, characterized in that, The mass ratio of the water-reducing agent to the defoamer is 100:(3~5).
9. The conductive concrete using gold tailings sand as the complete aggregate according to claim 7, characterized in that, The water-reducing agent includes a polycarboxylate water-reducing agent; The defoamer includes silicone defoamers.
10. A method for preparing conductive concrete using gold tailings sand as the complete aggregate, as described in any one of claims 1 to 9, characterized in that, Includes the following steps: One-dimensional conductive material is physically broken down to obtain a broken one-dimensional conductive material. The zero-dimensional conductive material was mixed with water and subjected to a first ultrasonic dispersion to obtain an aqueous dispersion of the zero-dimensional conductive material. The aqueous dispersions of the dispersed one-dimensional conductive material and the zero-dimensional conductive material are mixed, a surface modifier is added, and a second ultrasonic dispersion is performed to obtain a conductive material dispersion. Inorganic gel material, fly ash and gold tailings sand are mixed to obtain a mixed dry material; The conductive material dispersion and the dry mixture are mixed, stirred, and then poured into molds to obtain conductive concrete.