Graphite tailing full-doped ultra-high performance concrete and preparation method thereof
By utilizing a ternary cementitious material system of cement-fly ash microspheres-silica fume to prepare ultra-high performance concrete with full-volume graphite tailings, the problem of low graphite tailings usage was solved, achieving efficient utilization of graphite tailings and improved concrete performance.
Patent Information
- Application Number
- CN202411350511.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2024-09-26
- Publication Date
- 2025-11-28
- Estimated Expiration
- 2044-09-26
AI Technical Summary
In existing technologies, the amount of graphite tailings used in the preparation of ultra-high performance concrete is relatively low, resulting in the inefficient utilization of graphite tailings and environmental pollution caused by their accumulation.
A method for preparing ultra-high performance concrete using graphite tailings with full admixture was adopted. By using a ternary cementitious material system composed of cement, fly ash microspheres, and silica fume, the matrix density and workability of graphite tailings UHPC were controlled. By using reasonable mixing water and admixture dosages, concrete with excellent mechanical and workability was prepared.
This has enabled the efficient utilization of graphite tailings, alleviated the ecological problems caused by graphite tailings accumulation, and improved the mechanical and workability of concrete.
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Abstract
Description
TECHNICAL FIELD
[0001] The application belongs to the field of ultra-high performance concrete, and particularly relates to a full-mixing-amount graphite tailing ultra-high performance concrete and a preparation method thereof. BACKGROUND
[0002] Ultra-high performance concrete (UHPC) has ultra-high mechanical properties, ultra-high durability and high impermeability, and is considered as one of the most excellent cement-based composite materials in the past three decades, and is a hot research direction in the current civil engineering material and structure research field. Generally, all coarse aggregates are removed in the preparation of UHPC, and only a large amount of fine sand with a particle size of less than 0.6 mm is used as aggregate filling, and the total use amount of fine aggregate is about 1200 kg / m 3 , which is much larger than that of ordinary concrete. Although this optimizes the uniformity of the matrix, the high demand for fine sand significantly increases the preparation cost and energy consumption, hindering the further popularization and use of UHPC.
[0003] There are a large amount of solid slag graphite tailings in the process of graphite mining and processing. About 13 tons of graphite tailings are generated for every ton of graphite extracted by flotation method. The long-term accumulation of graphite tailings occupies land and deteriorates the surrounding environment, erodes the soil, and produces dust that pollutes the air. China, as the main producer, accounts for more than 50% of the global total graphite production. In 2022, for example, the world's graphite output was 1.3 million tons, with China accounting for about 65%, meaning that China's graphite tailings emissions in 2022 alone exceeded 10.985 million tons.
[0004] There are certain research foundations in the preparation of traditional building production raw materials such as building bricks, cement, mortar concrete and ceramics using graphite tailings. For example, according to the research results of the documents “Status of Graphite Tailing Resource Utilization”, “Optimization Analysis of Graphite Tailing Cement Mortar Mix Proportion”, “Research on Mechanical Properties and Conductive Properties of Graphite Tailing Concrete”, due to technical limitations, the optimal mixing amount of graphite tailings for replacing traditional aggregates to prepare cement-based composite materials is approximately between 10% and 20%, and the specific amount is approximately between 0 and 200 kg / m 3 . The composition of UHPC involves aggregates, quartz powder, cement, fly ash, silica fume and other particulate materials. Reasonable matching of the proportions of these materials can make the composite particles achieve the best chemical composition and physical performance matching form, which is beneficial to enhancing the mechanical properties and durability of UHPC. SUMMARY
[0005] The application aims to solve the problem that the use amount of graphite tailings is low when graphite tailings are used for concrete preparation in the field of cement-based composite materials, and further provides a full-mixing-amount graphite tailing ultra-high performance concrete and a preparation method thereof.
[0006] A kind of full-mixing amount graphite tailings ultra-high performance concrete is made of 773-950 parts by mass of cement, 140-240 parts of silica fume, 180-240 parts of superfine fly ash microbead, 1142-1333 parts of graphite tailings, 31.2-50.4 parts of high efficiency water reducing agent, 0-4.8 parts of defoaming agent and 240-264 parts of water.
[0007] The preparation method of the above-mentioned full-mixing amount graphite tailings ultra-high performance concrete is specifically carried out by the following steps:
[0008] I. 773-950 parts by mass of cement, 140-240 parts of silica fume, 180-240 parts of superfine fly ash microbead, 1142-1333 parts of graphite tailings, 31.2-50.4 parts of high efficiency water reducing agent, 0-4.8 parts of defoaming agent and 240-264 parts of water are taken as raw materials;
[0009] II. Cement, silica fume, superfine fly ash microbead and graphite tailings are added to a mixer to obtain aggregate, and the aggregate is pre-mixed for 120 s to make the dry-mixed aggregate uniform;
[0010] III. The high efficiency water reducing agent, defoaming agent and water are mixed to obtain an admixture mixture, the admixture mixture is divided into two parts in a mass ratio of 80%, 20%, 80% of the admixture mixture is added to the mixer and stirred for 180 s, the stirring is stopped, and then 20% of the admixture mixture is added to the mixer and stirred for 300 s, the mixer is turned off, the material is discharged, the test piece is prepared and cured to obtain the full-mixing amount graphite tailings ultra-high performance concrete.
[0011] The beneficial effects of the present application are:
[0012] The present application uses graphite tailings as the entire aggregate to prepare ultra-high performance concrete, which helps to promote the application of ultra-high performance concrete and alleviate the ecological problems caused by the large accumulation of graphite tailings to a great extent.
[0013] The present application controls the matrix density of graphite tailings UHPC by using a ternary cementitious material system composed of cement-fly ash-silica fume, and successfully prepares full-mixing amount graphite tailings UHPC with excellent mechanical properties by utilizing the interaction between different particles.
[0014] The present application controls the workability of graphite tailings UHPC by reasonably controlling the amount of mixing water and the dosage of admixture, and successfully prepares full-mixing amount graphite tailings UHPC with excellent workability. DETAILED DESCRIPTION
[0015] Embodiment 1: The full-doped amount of graphite tailings ultra-high performance concrete according to the embodiment is composed of 773-950 parts of cement, 140-240 parts of silica fume, 180-240 parts of superfine fly ash microbeads, 1142-1333 parts of graphite tailings, 31.2-50.4 parts of high efficiency water reducing agent, 0-4.8 parts of defoaming agent, and 240-264 parts of water.
[0016] Embodiment 2: The concrete according to the embodiment is different from that of Embodiment 1 in that it is composed of 888 parts of cement, 144 parts of silica fume, 192 parts of superfine fly ash microbeads, 1176 parts of graphite tailings, 40.8 parts of high efficiency water reducing agent, 2.4 parts of defoaming agent, and 246 parts of water. The rest is the same as Embodiment 1.
[0017] Embodiment 3: The concrete according to the embodiment is different from that of Embodiment 1 in that the cement is P.Ⅱ 52.5 ordinary portland cement, the 28d compressive strength is 55.75 MPa, the 28d flexural strength is 7 MPa, and the density is 3100 kg / m 3 . The rest is the same as Embodiment 1.
[0018] Embodiment 4: The concrete according to the embodiment is different from that of Embodiment 1 in that the graphite tailings are from Jixi City, Heilongjiang Province, and the particle size range is 0-0.6 mm. The rest is the same as Embodiment 1.
[0019] Embodiment 5: The concrete according to the embodiment is different from that of Embodiment 1 in that the water is tap water. The rest is the same as Embodiment 1.
[0020] Embodiment 6: The concrete according to the embodiment is different from that of Embodiment 1 in that the silica fume has the following properties: water demand ratio is 125%, loss on ignition ratio is 1.45%, apparent density is 2214 kg / m 3 , specific surface area is 19500 m 2 / kg; 7d activity index is 107%, and 28d activity index is 122.5%. The rest is the same as Embodiment 1.
[0021] Embodiment 7: The concrete according to the embodiment is different from that of Embodiment 1 in that the superfine fly ash microbeads have the following properties: water demand ratio is 90%, loss on ignition ratio is 0.2%, apparent density is 2500 kg / m 3 , specific surface area is 2431 m 2 / kg; 7d activity index is 80%, and 28d activity index is 115%. The rest is the same as Embodiment 1.
[0022] Embodiment eight: the difference between this embodiment and embodiment one is that the superplasticizer is polycarboxylic acid superplasticizer, the actual water-reducing rate is 30%, and the solid content is 25%; the defoaming agent is white powder, the pH value is 7.0, and the defoaming performance is actually measured as 1.907 g / mL. The others are the same as those in embodiment one.
[0023] Embodiment nine: the preparation method of the full-doped graphite tailings ultra-high performance concrete is specifically performed according to the following steps:
[0024] I. 773-950 parts of cement, 140-240 parts of silica fume, 180-240 parts of superfine fly ash microbeads, 1142-1333 parts of graphite tailings, 31.2-50.4 parts of superplasticizer, 0-4.8 parts of defoaming agent and 240-264 parts of water are taken as raw materials according to mass fraction;
[0025] II. The cement, silica fume, superfine fly ash microbeads and graphite tailings are added into a mixer to obtain aggregates, and the aggregates are pre-mixed for 120 s to uniformly dry-mix the aggregates;
[0026] III. The superplasticizer, defoaming agent and water are mixed to obtain an admixture, the admixture is divided into two parts according to a mass ratio of 80%, 20%, 80% of the admixture is added into the mixer and stirred for 180 s, the stirring is stopped, 20% of the admixture is added into the mixer and stirred for 300 s, then the mixer is turned off, the material is discharged, the test piece is prepared and cured, and the full-doped graphite tailings ultra-high performance concrete is obtained.
[0027] Embodiment ten: the difference between this embodiment and embodiment nine is that the stirring speed of the mixer in step II is constant at 60 r / min. The others are the same as those in embodiment nine.
[0028] The effect of the application is verified through the following tests:
[0029] The specific raw materials and specifications used in the examples and comparative examples are as follows:
[0030] The cement is P. II 52.5 ordinary portland cement, the 28d compressive strength is 55.75 MPa, the 28d flexural strength is 7 MPa, and the density is 3100 kg / m 3 The particle size range of the graphite tailings is 0-0.6 mm. The experimental water is ordinary tap water. The superplasticizer is polycarboxylic acid superplasticizer, the actual water-reducing rate is 30%, and the solid content is 25%. The defoaming agent is XP-2 type high-efficiency solid defoaming powder, white powder, the pH value is measured as 7.0, and the defoaming performance is actually measured as 1.907 g / mL. The water demand ratio of the silica fume experimental product is 125%, the loss on ignition ratio is 1.45%, and the apparent density is 2214 kg / m 3The specific surface area is 19500 m 2 / kg; the 7d activity index is 107%, and the 28d activity index is 122.5%. The fly ash micro-bead particle size experimental supplies have a water demand ratio of 90%, a loss on ignition ratio of 0.2%, and an apparent density of 2500 kg / m 3 The specific surface area is 2431 m 2 The specific surface area is 2431 m 2 / kg, the 7d activity index is 80%, and the 28d activity index is 115%.
[0031] The stirrer is a GMP50 type vertical shaft planetary stirrer, and the rotating speed is 60 r / min.
[0032] Raw material components
[0033] The chemical components of the cementitious material used in the test are as follows (%)
[0034]
[0035] Experimental method:
[0036] 1. Workability: The spreadability of the fresh UHPC is tested according to the “Standard Test Methods for Properties of Fresh Ordinary Concrete GB / T 50080-2002”.
[0037] 2. Mechanical properties: The compressive strength and flexural strength of the fresh UHPC are tested according to the “Method for Testing Strength of Cement Mortar (ISO Method) GB / T 17871-2021”.
[0038] Method:
[0039] I. Add cement, silica fume, ultra-fine fly ash micro-beads and graphite tailings into the stirrer to obtain aggregate, and pre-stir the aggregate for 120 s to make the dry mixing of the aggregate uniform;
[0040] II. Mix the high-efficiency water reducing agent, defoaming agent and water to obtain an admixture mixture, divide the admixture mixture into two parts according to the mass ratio of 80% and 20%, add the 80% part of the admixture mixture into the stirrer and stir for 180 s, stop stirring, then add the 20% part of the admixture mixture into the stirrer and stir for 300 s, turn off the stirrer, discharge, prepare test pieces, and cure to obtain the full-dose graphite tailings ultra-high performance concrete.
[0041] Specific implementation case one:
[0042] In this embodiment, water is 240 parts, cement is 870 parts, graphite tailings are 1200 parts, silica fume is 141 parts, micro-beads are 188 parts, water reducing agent is 40.8 parts, and defoaming agent is 2 parts.
[0043] Comparative example one:
[0044] The difference from Example One is that the mixing water amount of the mixture ratio is changed to 246 parts.
[0045] Comparative Example Two:
[0046] The difference from Example One is that the mixing water amount of the mixture ratio is changed to 252 parts.
[0047] Comparative Example Three:
[0048] The difference from Example One is that the mixing water amount of the mixture ratio is changed to 258 parts.
[0049] Comparative Example Four:
[0050] The difference from Example One is that the mixing water amount of the mixture ratio is changed to 264 parts.
[0051] The test results are shown in the table.
[0052] Table 1
[0053]
[0054] In combination with Table 1, the experimental results and analysis are as follows:
[0055] As shown in the data in Table 1, as the mixing water amount is gradually increased from 240 parts to 264 parts, the flexural and compressive strengths of the ultra-high strength concrete show a clear downward trend. The 28d compressive strength of Comparative Example Four is only 86% of the 28d strength of the test piece of Example One. However, the fluidity is greatly improved with the increase of the water-binder ratio.
[0056] Specific Implementation Case Two:
[0057] In this example, the water is 230 parts, the cement is 774 parts, the graphite tailings are 1333 parts, the silica fume is 125 parts, the microbeads are 167 parts, the water reducing agent is 36 parts, and the defoaming agent is 2 parts, i.e., the binder-sand ratio is 0.8. The water reducing agent and water are liquids, and the rest are solids. Stirring is performed at a speed of 60 r / min
[0058] Comparative Example Five:
[0059] The difference from Example Two is that the amount of graphite tailings is changed to 1263 parts, the amount of cement is changed to 824 parts, the amount of silica fume is changed to 133 parts, the amount of microbeads is changed to 178 parts, i.e., the binder-sand ratio is changed to 0.9, and the proportions among the cementitious materials remain unchanged.
[0060] Comparative Example Six:
[0061] The difference from Example Two is that the amount of graphite tailings is changed to 1200 parts, the amount of cement is changed to 870 parts, the amount of silica fume is changed to 141 parts, the amount of microbeads is changed to 188 parts, i.e., the binder-sand ratio is changed to 1.0, and the proportions among the cementitious materials remain unchanged.
[0062] Comparative Example Seven:
[0063] The difference between this example and Example Two is that the amount of graphite tailings is changed to 1142 parts, the amount of cement is changed to 912 parts, the amount of silica fume is changed to 147 parts, and the amount of microbeads is changed to 197 parts, i.e. the cement-sand ratio is changed to 1.1, and the proportions between the cementitious materials remain unchanged.
[0064] Comparative Example Eight:
[0065] The difference between this example and Example Two is that the amount of graphite tailings is changed to 1090 parts, the amount of cement is changed to 949 parts, the amount of silica fume is changed to 154 parts, and the amount of microbeads is changed to 205 parts, i.e. the cement-sand ratio is changed to 1.2, and the proportions between the cementitious materials remain unchanged.
[0066] Table 2
[0067]
[0068] Experimental Results and Analysis:
[0069] As shown in the data in Table 2, the 28-day compressive and flexural strengths of the concrete change very little with changes in the cement-sand ratio, and the trend is not obvious. However, when the amount of graphite tailings is 1090 parts, the strengths change significantly. The spread of Examples Two through Eight is 633, 745, 839, 873, and 928 mm, respectively, and the fluidity gradually increases with the increase in cementitious materials.
[0070] Specific Implementation Case Three:
[0071] This example includes 258 parts of water, 1080 parts of cement, 1200 parts of graphite tailings, 120 parts of silica fume, 40.8 parts of water reducing agent, and 2 parts of defoaming agent. The water reducing agent and water are liquids, and the rest are solids. They are stirred at a speed of 60 r / min.
[0072] Comparative Example Nine:
[0073] The difference between this example and Example Three is that the amount of silica fume is changed to 180 parts.
[0074] Comparative Example Ten:
[0075] The difference between this example and Example Three is that the amount of silica fume is changed to 240 parts.
[0076] Comparative Example Eleven:
[0077] The difference between this example and Example Three is that the amount of silica fume is changed to 300 parts.
[0078] Comparative Example Twelve:
[0079] The difference between the example three and the example four is that the silica fume is changed to 360 parts.
[0080] Table 3
[0081]
[0082] Experimental results and analysis:
[0083] As shown in Table 3, the 28d strength of the comparative example nine is 117.6% of the 28d strength of the comparative example twelve, and the strength is obviously improved. When the amount of silica fume is more than 180, the flexural and compressive strength of the ultra-high strength concrete decreases obviously with the increase of the mass ratio of silica fume. According to the data, the optimal amount of silica fume should be between 120 parts and 240 parts of the cementitious material. The expansion degree of this group is (903-803-700-673-642), and it can be seen that silica fume has greater water absorption, and a higher amount of silica fume leads to a decrease in fluidity.
[0084] Specific implementation case four:
[0085] In this example, water is 258 parts, cement is 960 parts, graphite tailings are 1200 parts, silica fume is 120 parts, microbeads are 120 parts, water reducing agent is 40.8 parts, and defoaming agent is 2 parts. The water reducing agent and water are liquids, and the rest are solids. Stir at a speed of 60 r / min.
[0086] Comparative example thirteen:
[0087] The difference between the example four and the comparative example thirteen is that the microbead is changed to 180 parts.
[0088] Comparative example fourteen:
[0089] The difference between the example four and the comparative example fourteen is that the microbead is changed to 240 parts.
[0090] Comparative example fifteen:
[0091] The difference between the example four and the comparative example fifteen is that the microbead is changed to 300 parts.
[0092] Comparative example sixteen:
[0093] The difference between the example four and the comparative example sixteen is that the microbead is changed to 360 parts.
[0094] Table 4
[0095]
[0096] Experimental results and analysis:
[0097] As shown in Table 4 data, the increase of microbead fraction will slightly reduce the compressive and flexural strength of UHPC. However, microbead has the function of improving the fluidity of concrete, and the spread of this group is (768-820-873-980-847), so it can be seen that even a small increase in the proportion of microbeads will greatly improve the fluidity. Considering the compressive strength, flexural strength and working performance, the best mixing amount of microbeads is between 120 parts and 180 parts.
[0098] Case five:
[0099] This example water 258 parts, cement 870 parts, graphite tailings 1200 parts, silica fume 141 parts, microbead 188 parts, water reducing agent 31.2 parts, defoaming agent 2 parts. The water reducing agent and water are liquids, and the rest are solids. Stir at a speed of 60 r / min.
[0100] Comparative example seventeen:
[0101] The difference from example five is that the fraction of water reducing agent is changed to 36 parts.
[0102] Comparative example eighteen:
[0103] The difference from example five is that the fraction of water reducing agent is changed to 40.8 parts.
[0104] Comparative example nineteen:
[0105] The difference from example five is that the fraction of water reducing agent is changed to 45.6 parts.
[0106] Comparative example twenty:
[0107] The difference from example five is that the fraction of water reducing agent is changed to 50.4 parts.
[0108] Table 5
[0109]
[0110]
[0111] Experimental results and analysis:
[0112] As shown in Table 5 data, with the gradual increase of water reducing agent, the flexural and compressive strength of concrete first increases and then decreases, and the 28d strength of comparative example eighteen is 116.9% of the 28d strength of example five. According to the data analysis, the most suitable water reducing agent content is between 31.2 and 40.8 parts. With the increase of high efficiency water reducing agent, the working performance first increases and then decreases, and the spread of this group is (713-745-833-770-753), and when the water reducing agent is increased to 40.8 parts, the fluidity will increase slightly.
[0113] Specific implementation case six:
[0114] The water is 258 parts, the cement is 870 parts, the graphite tailings are 1200 parts, the silica fume is 141 parts, the microbead is 188 parts, the water reducing agent is 40.8 parts, and the defoaming agent is 0 part. The water reducing agent and water are liquids, and the rest are solids. Stir at a speed of 60 r / min.
[0115] Comparative example twenty-one:
[0116] The difference from example six is that the defoaming agent is changed to 2.4 parts.
[0117] Comparative example twenty-two:
[0118] The difference from example six is that the defoaming agent is changed to 4.8 parts.
[0119] Comparative example twenty-three:
[0120] The difference from example six is that the defoaming agent is changed to 7.2 parts.
[0121] Comparative example twenty-four:
[0122] The difference from example six is that the defoaming agent is changed to 9.6 parts.
[0123] Table 6
[0124]
[0125] Experimental results and analysis:
[0126] As shown in the data in Table 6, with the increase of the defoaming agent, the flexural and compressive strength of the ultra-high strength concrete first increases and then decreases, reaching the maximum experimental data in comparative example twenty-one. Compared with comparative example twenty-four, the strength is 122.2% of that of comparative example twenty-four, so it is speculated that the optimal amount of defoaming agent is between 2.1 and 4.8 parts.
[0127] Specific implementation case seven:
[0128] The water is 258 parts, the cement is 720 parts, the graphite tailings are 1200 parts, the silica fume is 480 parts, the microbead is 0 part, the water reducing agent is 40.8 parts, and the defoaming agent is 2 parts. The water reducing agent and water are liquids, and the rest are solids. Stir at a speed of 60 r / min.
[0129] Comparative example twenty-five:
[0130] The difference from example seven is that the silica fume is changed to 360 parts, and the microbead is changed to 120 parts.
[0131] Comparative example twenty-six:
[0132] The difference between Example Seven and this example is that the silica fume is changed to 240 parts and the microbeads are changed to 240 parts.
[0133] Comparative Example Twenty-Seven:
[0134] The difference between Example Seven and this example is that the silica fume is changed to 120 parts and the microbeads are changed to 360 parts.
[0135] Comparative Example Twenty-Eight:
[0136] The difference between Example Seven and this example is that the silica fume is changed to 0 parts and the microbeads are changed to 480 parts.
[0137] Table 7
[0138]
[0139] Experimental Results and Analysis:
[0140] As shown in the data in Table 7, as the amount of silica fume decreases and the amount of microbeads increases, the flowability of the UHPC gradually increases. The spread of this group is (716-745-807-851-882). The incorporation of microbeads makes the overall flowability better, and the decrease in the amount of silica fume makes the overall water demand not tight, so the flowability increases. In terms of mechanical properties, as both change, the compressive strength and flexural strength show a trend of first increasing and then decreasing, reaching a maximum in Comparative Example Twenty-Six. This indicates that there is an optimal ratio between the amount of silica fume and the amount of microbeads, which should be around 1 to 1.
[0141] Performance Optimization
[0142] Based on the mix proportion range: cement 773-950 parts, graphite tailings 1142-1333 parts, water 240-264 parts, water reducing agent 31.2-40.8 parts, defoaming agent 2.4-4.8 parts, silica fume 180-240 parts, and microbeads 180-240 parts. The mix proportion is optimized using the MAA model based on the particle size distribution of graphite tailings, cement, silica fume, and microbeads, and a mix proportion is obtained. The amounts of mixing water, water reducing agent, and defoaming agent are adjusted to obtain the following mix proportion:
[0143] The mix proportion is cement 888 parts, graphite tailings 1176 parts, silica fume 144 parts, microbeads 192 parts, water reducing agent 40.8 parts, and defoaming agent 2.4 parts.
[0144]
[0145] According to the above research range, the flexural strength and compressive strength of the graphite tailings UHPC mixing proportion optimized by MAA are obviously improved, the 28d flexural strength is 16.84MPa, and the 28d compressive strength is 120.73, which reaches the maximum compressive strength in all experimental groups. The expansion degree is 645mm, which meets the category of self-compacting concrete, and if higher requirements are required for fluidity, the amount of water reducing agent and mixing water can be further adjusted according to the scope of the application.
Claims
1. A full-dose graphite tailings ultra-high performance concrete, characterized by The concrete is composed of 773-950 parts of cement, 140-240 parts of silica ash, 180-240 parts of superfine fly ash microbeads, 1142-1333 parts of graphite tailings, 31.2-50.4 parts of high efficiency water reducing agent, 0-4.8 parts of defoaming agent and 240-264 parts of water by mass fraction; the preparation method of the full-dose graphite tailings ultra-high performance concrete is specifically as follows: I. 773-950 parts of cement, 140-240 parts of silica ash, 180-240 parts of superfine fly ash microbeads, 1142-1333 parts of graphite tailings, 31.2-50.4 parts of high efficiency water reducing agent, 0-4.8 parts of defoaming agent and 240-264 parts of water are taken as raw materials by mass fraction; II. The cement, silica ash, superfine fly ash microbeads and graphite tailings are added into a mixer to obtain aggregates, and the aggregates are pre-mixed for 120 seconds to make the aggregates dry-mixed uniformly; III. The high efficiency water reducing agent, defoaming agent and water are mixed to obtain an admixture mixture, the admixture mixture is divided into two parts with a mass ratio of 80%, 20%, 80% of the admixture mixture is added into the mixer and stirred for 180 seconds, the stirring is stopped, 20% of the admixture mixture is added into the mixer and stirred for 300 seconds, then the mixer is turned off, the material is discharged, the test piece is prepared and cured to obtain the full-dose graphite tailings ultra-high performance concrete.
2. A fully dosed graphite tailings ultra high performance concrete according to claim 1, characterized in that The concrete is composed of 888 parts of cement, 144 parts of silica ash, 192 parts of superfine fly ash microbeads, 1176 parts of graphite tailings, 40.8 parts of high efficiency water reducing agent, 2.4 parts of defoaming agent and 246 parts of water.
3. A fully dosed graphite tailings ultra high performance concrete according to claim 1, characterized by The cement is P. II 52.5 ordinary portland cement, 28d compressive strength is 55.75 MPa, 28d flexural strength is 7 MPa, density is 3100 kg / m 3 .
4. A fully dosed graphite tailings ultra high performance concrete according to claim 1, characterized by The graphite tailings are produced in Jixi City, Heilongjiang Province, and the particle size range is 0-0.6 mm.
5. A fully dosed graphite tailings ultra high performance concrete according to claim 1, characterized by The water is tap water.
6. A fully dosed graphite tailings ultra high performance concrete according to claim 1, characterized by The silica ash has the following properties: water demand ratio 125%, loss on ignition ratio 1.45%, apparent density 2214kg / m 3 , specific surface area 19500m 2 / kg; 7d activity index 107%, 28d activity index 122.5%.
7. A fully dosed graphite tailings ultra high performance concrete according to claim 1, characterized by The superfine fly ash microbead has the following performances: water demand ratio 90%, burning loss ratio 0.2%, apparent density 2500kg / m 3 , specific surface area 2431m 2 / kg; 7d activity index 80%, 28d activity index 115%.
8. A fully dosed graphite tailings ultra high performance concrete according to claim 1, characterized by The high efficiency water reducing agent is a polycarboxylic acid high performance water reducing agent, the actual water-reducing rate is 30%, and the solid content is 25%; the defoaming agent is a white powder, the PH value is 7.0, and the actual defoaming performance is 1.907 g / mL.
9. A fully dosed graphite tailings ultra high performance concrete according to claim 1, characterized by The stirring speed of the mixer in step II is constant at 60 r / min.