High-strength green concrete based on eggshell particles and waste glass powder and preparation method thereof

Abstract

The invention discloses high-strength green concrete based on eggshell particles and waste glass powder and a preparation method thereof.The high-strength green concrete is prepared from, by weight, 555 kg to 595 kg of fine aggregate, 1290 kg to 1320 kg of coarse aggregate, 178.4 kg to 312.2 kg of cement, 44.6 kg to 133.8 kg of eggshell particles, 44.6 kg to 133.8 kg of waste glass powder, 53.53 kg to 93.66 kg of water and 4.46 kg of water reducing agent; the preparation method comprises the following specific preparation steps: mixing the raw materials according to the weight ratio to prepare the high-strength green concrete; according to the invention, a large amount of waste glass, waste eggshells and other construction wastes and kitchen wastes are used as raw materials, waste gas and wastes are consumed, resource reutilization of wastes is realized, high energy consumption generated by a traditional method is reduced, and the method is a green recycling technology; the inventive concrete can be used in structural load members.

Description

Technical Field

[0001] The present invention relates to the technical field of concrete preparation, and specifically relates to a high-strength green concrete based on eggshell particles and waste glass powder and a preparation method thereof. Background Art

[0002] Concrete is one of the most widely used materials in modern society, and a large amount of carbon emissions are generated during its production and transportation. Traditional concrete needs to be improved to meet the requirements of the era of high energy efficiency and low emissions. In concrete, cement is the source of a large amount of carbon emissions. Reducing the carbon emissions of cement can thus reduce the carbon emissions of concrete. The existing improvement of concrete mainly involves partially replacing cement with industrial waste residues or solid waste, and using their potential cementitious activity to reduce the amount of cement used, thereby reducing the high carbon emissions generated during the production of cement, and at the same time realizing the resource utilization of solid waste. This technology optimizes the concrete mix ratio by adjusting the admixture ratio and has been applied in fields such as building foundations and road engineering. However, in practical applications, it faces problems such as the activation of alternative materials depending on an alkaline environment, slow early strength development, and the influence of fluctuations in the solid waste composition on the stability of concrete. At the same time, the uneven regional distribution of industrial solid waste limits large-scale application, and some heavy metal-containing waste residues may pose environmental risks, restricting the coordinated improvement of the performance and ecological benefits of low-carbon concrete.

[0003] In the prior art, such as the patent application CN202310831538, "A Preparation Method of a Slag-Fly Ash-Based Geopolymer Composite Cementitious Material", it is proposed to use a double admixture of fly ash and slag to replace 50% of the cement, and improve the cementitious activity through alkali activation. However, it relies on a high-concentration alkaline activator, resulting in an increased risk of alkali-aggregate reaction inside the concrete, and the transportation and construction safety of the alkaline solution are limited; the patent application CN202111230535, "A Steel Slag-Based Permeable Concrete and Preparation Process", uses steel slag fine powder to replace 30% of the cement. Although the carbon emissions are reduced, the fluctuations in the content of free calcium oxide and magnesium oxide in the steel slag are likely to cause poor volume stability of the concrete, and the problem of late-stage expansion and cracking is prominent, and the risk of heavy metal leaching in the steel slag has not been completely solved. Both technologies are difficult to balance mechanical properties, durability and environmental safety due to the inherent defects of the alternative materials, restricting the promotion in practical engineering. Summary of the Invention

[0004] To overcome the defects of the above-mentioned existing technologies, the present invention proposes a high-strength green concrete based on eggshell particles and waste glass powder and its preparation method. By calcining and activating the eggshell particles at high temperature and then co-doping them with waste glass powder into the concrete system, a composite cementitious network is formed by utilizing the alkaline slow-release characteristics of the calcium carbonate and nano-calcium oxide mixture in the eggshells and the pozzolanic effect of the siliceous components of the waste glass powder. Without relying on high-concentration alkaline activators, the cement dosage can be reduced by 30%-40%. This not only effectively avoids the risk of alkali-aggregate reaction, but also the micro-aggregate filling effect of the micro-calcium carbonate particles in the eggshells after calcination and the stable chemical characteristics of the active silicon dioxide in the waste glass powder synergistically improve the early strength development rate and volume stability of the concrete. At the same time, the eggshells and waste glass, as urban solid wastes, are fully utilized for resource recovery. Their non-heavy metal leaching characteristics ensure the environmental safety of the entire life cycle of the concrete, ultimately forming a green concrete material with low carbon emissions, high mechanical properties, and ecological friendliness.

[0005] To achieve the above object, the technical solution adopted by the present invention is as follows:

[0006] A high-strength green concrete based on eggshell particles and waste glass powder, the raw materials of which are weighed by weight ratio, including: fine aggregate 582 - 586 kg, coarse aggregate 1293 - 1300 kg, cement 178.4 - 312.2 kg, eggshell particles 44.6 - 133.8 kg, waste glass powder 44.6 - 133.8 kg, water 53.53 - 93.66 kg, and water reducer 4.46 kg.

[0007] The fine aggregate uses natural river sand, specifically medium sand with a particle size of 0.3 mm - 2.36 mm; among them, the proportion of coarse particles with a particle size ≥ 1.18 mm is 25% - 30%, and the proportion of fine particles with a particle size < 1.18 mm is 70% - 75%.

[0008] The particle size range of the coarse aggregate is 4.57 mm - 20 mm, among which, 4.75 mm - 9.5 mm accounts for 25 - 30%, 9.5 mm - 16 mm accounts for 45 - 55%, and 16 mm - 20 mm accounts for 20 - 25%.

[0009] The particle size of the eggshell particles is 15 - 20 μm.

[0010] The proportion of powder particles with a particle size of 15 - 20 μm in the waste glass powder is ≥ 90%, and the rest are coarse particles > 20 μm that are not completely crushed or fine powder < 15 μm.

[0011] The cement uses ordinary Portland cement; the water reducer is a polycarboxylic acid-based high-efficiency water reducer with a water reduction rate of 25%.

[0012] A preparation method of a high-strength green concrete based on eggshell particles and waste glass powder specifically includes the following steps:

[0013] Mix 44.6 - 133.8 kg of eggshell particles, 44.6 - 133.8 kg of waste glass powder, 1290 - 1320 kg of coarse aggregate, 555 - 595 kg of fine aggregate, add 178.4 - 356.8 kg of cement, then add 111.5 - 133.8 kg of water and 4.46 kg of water reducing agent, and mix and stir them to finally obtain the target product, high-strength green concrete.

[0014] The method for obtaining the waste glass powder is as follows: Sieve and then ball-mill the washed, dried and crushed waste glass to obtain waste glass powder; in the waste glass powder, the proportion of powder particles with a particle size of 15 - 20 μm is ≥ 90%, and the rest are coarse particles that are not completely crushed and are > 20 μm or too fine powder < 15 μm.

[0015] The method for obtaining the eggshell particles is as follows: Wash the eggshells, dry them at 60 - 80 °C for 4 - 5 hours, then crush them, remove the residual egg membranes in the separated broken eggshells by air separation or screening, and remove metal impurities by magnetic separation; then, calcine the broken eggshells at 900 - 950 °C for 4 - 5 hours, and ball-mill the calcined broken eggshells until the particle size reaches 15 - 20 μm.

[0016] The water-binder ratio of the obtained high-strength green concrete is 0.25 - 0.3. The added water is added by the method of spraying while stirring until the addition of water is completed.

[0017] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0018] (1) The present invention uses a large amount of solid wastes, such as waste glass and waste eggshells, as raw materials, consumes the waste generated by food processing and construction waste, not only realizes the resource recycling of waste and garbage, but also reduces the high energy consumption in the production by traditional methods. It is a green utilization technology for producing high-strength concrete. The invented concrete can be used for high-strength stressed members, and has a wide application prospect and considerable benefits.

[0019] (2) The present invention uses the eggshells in the waste generated by food processing to solve the alkali-silica phenomenon that is likely to occur in waste glass in concrete, and produces a pozzolanic effect, which can effectively fill the pores of the concrete and increase the overall performance of the concrete, effectively solving the problem of reducing cement and decreasing the strength of the concrete.

[0020] (3) When the concrete prepared by the present invention ensures that the strength of the concrete is not less than 60 MPa, it can consume 30% of waste glass and 30% of waste eggshells. Compared with ordinary concrete C60, this method saves 60% of new building materials.

[0021] The present invention prepares high-strength green concrete by synergistically utilizing waste eggshells and waste glass powder. The alkaline slow-release property of bio-nano calcium oxide in the calcined eggshells is used to neutralize the potential alkali-silica reaction risk of waste glass. At the same time, the micro-aggregate filling of small particle size calcium carbonate particles and the pozzolanic effect of waste glass synergistically improve the density. On the premise of ensuring that the concrete strength is greater than 60 MPa, the solid waste resource utilization rate exceeds 60%, and the cement consumption can be reduced by up to 60%. This technology has three advantages: low-carbon emission reduction, harmless utilization of all components of solid waste, and high-performance guarantee. It can be widely applied to the field of building load-bearing components, significantly reducing the environmental load and economic cost. Detailed implementation mode

[0022] The following examples are used to further elaborate the present invention in detail, so that those skilled in the art can implement it with reference to the text of the specification.

[0023] Example 1

[0024] A method for preparing high-strength green concrete based on eggshell particles and waste glass powder specifically includes the following steps:

[0025] 44.6 kg of eggshell particles, 44.6 kg of waste glass powder, 1293 kg of coarse aggregate, 582 kg of fine aggregate, 312.2 kg of ordinary Portland cement are added, and 93.66 kg of water is added by the method of spraying while stirring. Finally, 4.46 kg of polycarboxylic acid type high-performance water reducer is added and mixed and stirred to finally obtain the target product, high-strength green concrete.

[0026] The waste glass powder is obtained by screening and ball milling the waste glass that has been cleaned, dried, and crushed. The proportion of powder particles with a particle size of 15-20 μm in the waste glass powder is greater than 90%, and the remaining particles are greater than 20 μm or the fine powder is less than 15 μm;

[0027] The eggshell particles are obtained by drying the cleaned eggshells at 80 °C for 5 hours, then crushing them, removing the residual egg membranes in the separated broken eggshells by air separation or screening, and removing metal impurities by magnetic separation; then, the broken eggshells are calcined at 950 °C for 5 hours, and the calcined broken eggshells are ball milled to a particle size of 20 μm.

[0028] The coarse aggregate with a particle size of 4.75 mm - 9.5 mm accounts for 27%, the coarse aggregate with a particle size of 9.5 mm - 16 mm accounts for 50%, and the coarse aggregate with a particle size of 16 mm - 20 mm accounts for 23%; in the fine aggregate, the coarse sand with a medium particle size ≥ 1.18 mm accounts for 25%, and the fine sand with a particle size < 1.18 mm accounts for 75%.

[0029] Finally, high-strength green concrete containing waste glass powder and eggshell particles is prepared. The solid waste consumed in this example accounts for 20%, and the cement accounts for 80%. After 28 days of standard curing, the compressive strength is about 87.6 MPa.

[0030] Example 2

[0031] A method for preparing high-strength green concrete based on eggshell particles and waste glass powder, specifically comprising the following steps:

[0032] Mix 44.6 kg of eggshell particles, 89.2 kg of waste glass powder with 1290 kg of coarse aggregate, 585 kg of fine aggregate, and add 312.2 kg of ordinary Portland cement. Then, add 133.8 kg of water and 4.46 kg of polycarboxylate-based superplasticizer while spraying and stirring to obtain the target product, high-strength green concrete, by mixing and stirring.

[0033] The waste glass powder is obtained by screening and ball milling the waste glass that has been cleaned, dried, crushed, and passed through a sieve; in the waste glass powder, the proportion of powder particles with a particle size of 15 - 20 μm is greater than 90%, and the remaining particles are greater than 20 μm or the fine powder is less than 15 μm.

[0034] The eggshell particles are obtained by drying the cleaned eggshells at 80°C for 5 hours, then crushing them, removing the residual egg membranes in the separated broken eggshells by air separation or screening, and removing metal impurities by magnetic separation; then, the broken eggshells are calcined at 940°C for 5 hours, and the calcined broken eggshells are ball milled to a particle size of 20 μm.

[0035] The 4.75 mm - 9.5 mm coarse aggregate accounts for 25%, the 9.5 mm - 16 mm coarse aggregate accounts for 53%, and the 16 mm - 20 mm coarse aggregate accounts for 22%; in the fine aggregate, the medium sand with a particle size ≥ 1.18 mm accounts for 30% of the coarse particles, and the medium sand with a particle size < 1.18 mm accounts for 70% of the fine particles.

[0036] Finally, high-strength green concrete containing waste glass powder and eggshell particles is prepared. In this example, the solid waste consumed accounts for 30%, and the cement accounts for 70%. After 28 days of standard curing, the compressive strength is approximately 80.2 MPa.

[0037] Example 3

[0038] A method for preparing high-strength green concrete based on eggshell particles and waste glass powder, specifically comprising the following steps:

[0039] Mix 44.6 kg of eggshell particles, 133.8 kg of waste glass powder with 1285 kg of coarse aggregate, 590 kg of fine aggregate, and add 267.6 kg of ordinary Portland cement. Then, add 111.5 kg of water and 4.46 kg of polycarboxylate-based superplasticizer while spraying and stirring to obtain the target product, high-strength green concrete, by mixing and stirring.

[0040] The waste glass powder is obtained by screening and then ball-milling the waste glass that has been cleaned, dried, and crushed; in the waste glass powder, the proportion of powder particles with a particle size of 15 - 20 μm is greater than 95%, and the remaining particles are greater than 20 μm or the overly fine powder is less than 15 μm;

[0041] The eggshell particles are obtained by drying the cleaned eggshells at 75°C for 5 hours, then crushing them, removing the residual egg membranes in the separated crushed eggshells by air separation or screening, and removing metal impurities by magnetic separation; then, the crushed eggshells are calcined at 900°C for 4 hours, and the calcined crushed eggshells are ball-milled to a particle size of 20 μm.

[0042] The coarse aggregate with a size of 4.75 mm - 9.5 mm accounts for 20%, the coarse aggregate with a size of 9.5 mm - 16 mm accounts for 55%, and the coarse aggregate with a size of 16 mm - 20 mm accounts for 25%; in the fine aggregate, the medium sand with a coarse particle size of ≥1.18 mm accounts for 25%, and the fine sand with a particle size of <1.18 mm accounts for 75%.

[0043] Finally, high-strength green concrete containing waste glass powder and eggshell particles is prepared. The solid waste consumed in this example contains 20% of cement. After 28 days of standard curing, the compressive strength is approximately 73.3 MPa.

[0044] Example 4

[0045] A method for preparing high-strength green concrete based on eggshell particles and waste glass powder specifically includes the following steps:

[0046] 44.6 kg of eggshell particles, 89.2 kg of waste glass powder, 1280 kg of coarse aggregate, 595 kg of fine aggregate, 312.2 kg of ordinary Portland cement are taken, and 120.42 kg of water and 4.46 kg of polycarboxylic acid type high-range water reducer are added by the method of spraying while stirring and then mixed and stirred to finally obtain the target product, high-strength green concrete.

[0047] The waste glass powder is obtained by screening and then ball-milling the waste glass that has been cleaned, dried, and crushed; in the waste glass powder, the proportion of powder particles with a particle size of 15 - 20 μm is greater than 95%, and the remaining particles are greater than 20 μm or the overly fine powder is less than 15 μm;

[0048] The eggshell particles are obtained by drying the cleaned eggshells at 70°C for 4 hours, then crushing them, removing the residual egg membranes in the separated crushed eggshells by air separation or screening, and removing metal impurities by magnetic separation; then, the crushed eggshells are calcined at 920°C for 5 hours, and the calcined crushed eggshells are ball-milled to a particle size of 20 μm.

[0049] Among the coarse aggregates, the coarse aggregates with a size of 5.50 mm account for 25%, the coarse aggregates with a size of 11 mm account for 50%, the coarse aggregates with a size ranging from 18.74.75 mm to 9.5 mm account for 25%, the coarse aggregates with a size ranging from 9.5 mm to 16 mm account for 50%, and the coarse aggregates with a size ranging from 16 mm to 20 mm account for 23%; among the fine aggregates, the medium sand with coarse particles having a particle size ≥ 1.18 mm accounts for 25%, and the medium sand with fine particles having a particle size < 1.18 mm accounts for 75%.

[0050] Finally, high-strength green concrete containing waste glass powder and eggshell particles is prepared. The solid waste consumed in this example contains 20% of cement. After 28 days of standard curing, the compressive strength is approximately 75.3 MPa.

[0051] Example 5

[0052] A preparation method of high-strength green concrete based on eggshell particles and waste glass powder specifically includes the following steps:

[0053] 89.2 kg of eggshell particles, 89.2 kg of waste glass powder, 1300 kg of coarse aggregates, 575 kg of fine aggregates, 267.6 kg of ordinary Portland cement are taken, and 133.8 kg of water and 4.46 kg of polycarboxylic acid type high-range water reducer are added by the method of spraying while stirring and mixing, and finally the target product, high-strength green concrete, is obtained.

[0054] The waste glass powder of the device is the waste glass powder obtained by screening and then ball-milling the waste glass that has been cleaned, dried and crushed; in the waste glass powder, the powder particles with a particle size of 15 - 20 μm account for more than 95%, and the remaining particles are greater than 20 μm or the fine powder is less than 15 μm;

[0055] The eggshell particles are the dried eggshells that have been cleaned, dried at 80 °C for 5 hours, then crushed, and the residual egg membranes in the crushed eggshells are removed by air separation or screening, and metal impurities are removed by magnetic separation; then, the crushed eggshells are calcined at 910 °C for 5 hours, and the calcined crushed eggshells are ball-milled to a particle size of 20 μm.

[0056] Among the coarse aggregates with a size ranging from 4.75 mm to 9.5 mm, they account for 27%, the coarse aggregates with a size ranging from 9.5 mm to 16 mm account for 50%, and the coarse aggregates with a size ranging from 16 mm to 20 mm account for 23%; among the fine aggregates, the medium sand with coarse particles having a particle size ≥ 1.18 mm accounts for 26%, and the medium sand with fine particles having a particle size < 1.18 mm accounts for 74%.

[0057] Finally, high-strength green concrete containing waste glass powder and eggshell particles is prepared. The solid waste consumed in this example contains 20% of cement. After 28 days of standard curing, the compressive strength is approximately 75.7 MPa.

[0058] Example 6

[0059] A preparation method of high-strength green concrete based on eggshell particles and waste glass powder, specifically including the following steps:

[0060] Mix 113.8 kg of eggshell particles, 89.2 kg of waste glass powder, 1310 kg of coarse aggregate, 570 kg of fine aggregate, 223 kg of ordinary Portland cement, then add 111.5 kg of water and 4.46 kg of polycarboxylate-based superplasticizer by the method of spraying while stirring, and finally obtain the target product, high-strength green concrete.

[0061] The waste glass powder is obtained by screening and ball milling the waste glass that has been cleaned, dried, crushed, and sieved; in the waste glass powder, the proportion of powder particles with a particle size of 15 - 20 μm is greater than 90%, and the remaining particles are greater than 20 μm or the fine powder is less than 15 μm;

[0062] The eggshell particles are obtained by drying the cleaned eggshells at 80°C for 5 hours, then crushing, removing the residual egg membranes in the crushed eggshells by air separation or screening, and removing metal impurities by magnetic separation; then, the crushed eggshells are calcined at 900°C for 5 hours, and the calcined crushed eggshells are ball milled to a particle size of 20 μm.

[0063] The coarse aggregate with a size of 4.75 mm - 9.5 mm accounts for 22%, the coarse aggregate with a size of 9.5 mm - 16 mm accounts for 53%, and the coarse aggregate with a size of 16 mm - 20 mm accounts for 25%; in the fine aggregate, the medium sand with a coarse particle size of ≥1.18 mm accounts for 25%, and the medium sand with a fine particle size of <1.18 mm accounts for 75%.

[0064] Finally, high-strength green concrete containing waste glass powder and eggshell particles is prepared. The solid waste consumed in this example contains 20% of cement. After 28 days of standard curing, the compressive strength is about 78 MPa.

[0065] Example 7

[0066] A preparation method of high-strength green concrete based on eggshell particles and waste glass powder, specifically including the following steps:

[0067] Mix 44.6 kg of eggshell particles, 133.8 kg of waste glass powder, 1320 kg of coarse aggregate, 560 kg of fine aggregate, 267.6 kg of ordinary Portland cement, then add 111.5 kg of water and 4.46 kg of polycarboxylate-based superplasticizer by the method of spraying while stirring, and finally obtain the target product, high-strength green concrete;

[0068] The waste glass powder is obtained by screening and ball milling the waste glass that has been cleaned, dried, crushed, and sieved; in the waste glass powder, the proportion of powder particles with a particle size of 15 - 20 μm is greater than 90%, and the remaining particles are greater than 20 μm or the fine powder is less than 15 μm;

[0069] The eggshell particles are obtained by cleaning and drying the eggshells, drying them at 80°C for 5 hours, then crushing them, removing the residual egg membranes in the separated crushed eggshells by air separation or screening, and removing metal impurities by magnetic separation; then, the crushed eggshells are calcined at a high temperature of 910°C for 5 hours, and the calcined crushed eggshells are ball-milled until the particle size reaches 20μm.

[0070] The coarse aggregate with a size of 4.75mm - 9.5mm accounts for 20%, the coarse aggregate with a size of 9.5mm - 16mm accounts for 55%, and the coarse aggregate with a size of 16mm - 20mm accounts for 25%; among the fine aggregates, the medium sand with a particle size ≥ 1.18mm accounts for 28%, and the fine sand with a particle size < 1.18mm accounts for 72%.

[0071] Finally, high-strength green concrete containing waste glass powder and eggshell particles is prepared. The solid waste consumed in this example accounts for 20% of the cement. After 28 days of standard curing, the compressive strength is about 77.2MPa.

[0072] Example 8

[0073] A preparation method of high-strength green concrete based on eggshell particles and waste glass powder specifically includes the following steps:

[0074] 89.2 kg of eggshell particles, 133.8 kg of waste glass powder, 1300 kg of coarse aggregate, 575 kg of fine aggregate, 223 kg of ordinary Portland cement are added, and 111.5 kg of water and 4.46 kg of polycarboxylate-based superplasticizer are mixed and stirred by the method of spraying and stirring simultaneously to finally obtain the target product, high-strength green concrete.

[0075] The waste glass powder is obtained by screening and ball-milling the waste glass that has been cleaned, dried and crushed; in the waste glass powder, the powder particles with a particle size of 15 - 20μm account for more than 90%, and the remaining particles are larger than 20μm or the fine powder is less than 15μm.

[0076] The eggshell particles are obtained by cleaning and drying the eggshells, drying them at 80°C for 5 hours, then crushing them, removing the residual egg membranes in the separated crushed eggshells by air separation or screening, and removing metal impurities by magnetic separation; then, the crushed eggshells are calcined at a high temperature of 920°C for 5 hours, and the calcined crushed eggshells are ball-milled until the particle size reaches 20μm.

[0077] The coarse aggregate with a size of 4.75mm - 9.5mm accounts for 25%, the coarse aggregate with a size of 9.5mm - 16mm accounts for 50%, and the coarse aggregate with a size of 16mm - 20mm accounts for 25%; among the fine aggregates, the medium sand with a particle size ≥ 1.18mm accounts for 30%, and the fine sand with a particle size < 1.18mm accounts for 70%.

[0078] Finally, high-strength green concrete containing waste glass powder and eggshell particles is obtained. The solid waste consumed in this example accounts for 20% of the cement. After 28 days of standard curing, the compressive strength is about 70.3 MPa.

[0079] Example 9

[0080] A preparation method of high-strength green concrete based on eggshell particles and waste glass powder specifically includes the following steps:

[0081] 133.8 kg of eggshell particles, 133.8 kg of waste glass powder, 1310 kg of coarse aggregate, 570 kg of fine aggregate, and 178.4 kg of ordinary Portland cement are added. Then, 111.5 kg of water and 4.46 kg of polycarboxylate-based superplasticizer are mixed and stirred by the method of spraying and stirring simultaneously to finally obtain the target product, high-strength green concrete.

[0082] The waste glass powder is obtained by screening and ball milling the waste glass that has been cleaned, dried, broken, and passed through a sieve. In the waste glass powder, the proportion of powder particles with a particle size of 15 - 20 μm is greater than 90%, and the remaining particles are greater than 20 μm or the fine powder is less than 15 μm;

[0083] The eggshell particles are prepared by drying the cleaned eggshells at 63 °C for 4 hours, then crushing them, removing the residual egg membranes in the separated broken eggshells by air separation or screening, and removing metal impurities by magnetic separation; then, the broken eggshells are calcined at 915 °C for 5 hours, and the calcined broken eggshells are ball milled to a particle size of 20 μm.

[0084] The coarse aggregate with a size of 4.75 mm - 9.5 mm accounts for 27%, the coarse aggregate within 9.5 mm - 16 mm accounts for 50%, and the coarse aggregate with a size of 16 mm - 20 mm accounts for 23%; among the fine aggregate, the coarse-grained medium sand with a particle size ≥ 1.18 mm accounts for 30%, and the fine-grained medium sand with a particle size < 1.18 mm accounts for 70%.

[0085] Finally, high-strength green concrete containing waste glass powder and eggshell particles is obtained. The solid waste consumed in this example accounts for 20% of the cement. After 28 days of standard curing, the compressive strength is about 64.8 MPa.

[0086] Comparative example

[0087] Comparative example 1

[0088] A green high-strength concrete, which is different from Example 1 in that waste glass powder is not added to the components.

[0089] The preparation steps of the concrete are as follows:

[0090] Mix the eggshell particles, waste glass powder, coarse aggregate, fine aggregate, cement, water and water reducer in the ratio of 44.6:0:1293:582:401.4:107.04:4.46. When mixing, first fully mix the cement, coarse aggregate and fine aggregate for 2 minutes, then sequentially add the eggshell particles and waste glass powder and mix for 2 minutes, and finally add water and water reducer and mix for 3 minutes to obtain high-strength green concrete containing waste glass powder and eggshell particles.

[0091] Comparative Example 2

[0092] A kind of green high-strength concrete, different from that in Example 1, is that eggshell particles are not added to the composition. The preparation steps of the concrete are as follows:

[0093] Mix the eggshell particles, waste glass powder, coarse aggregate, fine aggregate, cement, water and water reducer in the ratio of 0:44.6:1293:582:401.4:107.04:4.46. When mixing, first fully mix the cement, coarse aggregate and fine aggregate for 2 minutes, then sequentially add the eggshell particles and waste glass powder and mix for 2 minutes, and finally add water and water reducer and mix for 3 minutes to obtain high-strength green concrete containing waste glass powder and eggshell particles.

[0094] Comparative Example 3

[0095] A kind of high-strength concrete, different from that in Example 1, is that eggshell particles and waste glass powder are not added to the components.

[0096] The preparation steps of the concrete are as follows:

[0097] Mix the eggshell particles, waste glass powder, coarse aggregate, fine aggregate, cement, water and water reducer in the ratio of 0:0:1293:582:446.0:107.04:4.46. When mixing, first fully mix the cement, coarse aggregate and fine aggregate for 2 minutes, then sequentially add the eggshell particles and waste glass powder and mix for 2 minutes, and finally add water and water reducer and mix for 3 minutes to obtain ordinary high-strength concrete.

[0098] Performance detection test

[0099] Specimen size: 150mm×150mm×150mm

[0100] 1. Compressive strength test method

[0101] First, detect the appearance of the specimen. Measure the size of the specimen and calculate the compression area of the specimen. Secondly, move the specimen to the corresponding position for compression. Set the test parameters and apply pressure at a speed of 0.5kN / s until the specimen fails. Use multiple groups of specimens and calculate the compressive strength through the following formula and find the average value.

[0102] Compressive strength calculation formula:

[0103]

[0104] Where: f k - Compressive strength of the test piece, MPa;

[0105] f a - Failure load, N;

[0106] a - Compressive area of the test piece, mm 2 .

[0107] 2. Detection method for frost resistance performance

[0108] The rapid freeze-thaw cycle method is adopted to determine the frost resistance performance of concrete test pieces. After the test pieces treated by saturated water treatment are put into a rapid freeze-thaw testing machine, after 200 freeze-thaw cycles, the compressive strength of the concrete test pieces is tested, and the loss rate of compressive strength is tested.

[0109]

[0110] Where: λ - Loss rate of compressive strength;

[0111] f FT,0 - Compressive strength of the test piece during the 28-day curing period;

[0112] f FT,i - Compressive strength of the test piece under the i-th freeze-thaw cycle.

[0113] Table 1

[0114]

[0115]

[0116] The quantitative analysis of the technical effects of the present invention shows that: the 28-day compressive strengths of Examples 1-9 are all ≥ 64.8 MPa. Among them, the compressive strength of Example 9 is 24.03% lower than that of Comparative Example 1. After 200 freeze-thaw cycles, the compressive strength loss of 18.21% is still higher than 25% in the current specification, proving that the mechanical requirements of high-strength concrete can still be met after replacing 60% of cement with solid waste. Examples 4, etc. still show a better durability balance than conventional low-carbon concrete. Compared with the prior art, while maintaining high strength, the present invention replaces 20% - 60% of cement with solid waste to achieve a 20% - 60% reduction in carbon emissions, and breaks through the bottleneck of alkali-aggregate reaction and early strength attenuation of traditional solid waste concrete through the eggshell-glass composite cementitious system. Its core innovation lies in the chemical synergy of waste resources to achieve the triple performance optimization of "strength - low carbon - durability", providing a quantifiable and popularizable solution for green high-performance concrete.

Claims

1. A high-strength green concrete based on eggshell particles and waste glass powder, characterized in that, The raw materials are weighed by weight ratio and include: fine aggregate 555 - 595 kg, coarse aggregate 1290 - 1320 kg, cement 178.4 - 356.8 kg, eggshell particles 44.6 - 133.8 kg, waste glass powder 44.6 - 133.8 kg, water 111.5 - 133.8 kg, and water reducing agent 4.46 kg.

2. The high-strength green concrete based on eggshell particles and waste glass powder according to claim 1, wherein The fine aggregate uses natural river sand, specifically medium sand with a particle size of 0.3 mm - 2.36 mm; among them, the proportion of coarse particles with a particle size ≥ 1.18 mm is 25% - 30%, and the proportion of fine particles with a particle size < 1.18 mm is 70% - 75%.

3. A high-strength green concrete based on eggshell particles and waste glass powder, characterized in that, The particle size range of the coarse aggregate is 4.57 mm - 20 mm, among which, 4.75 mm - 9.5 mm accounts for 25 - 30%, 9.5 mm - 16 mm accounts for 45 - 55%, and 16 mm - 20 mm accounts for 20 - 25%.

4. A high-strength green concrete based on eggshell particles and waste glass powder, characterized in that, The particle size of the eggshell particles is 15 - 20 μm.

5. A high-strength green concrete based on eggshell particles and waste glass powder, characterized in that, In the waste glass powder, the proportion of powder particles with a particle size of 15 - 20 μm is ≥ 90%, and the rest are uncompletely crushed coarse particles > 20 μm or overly fine powder < 15 μm.

6. A high-strength green concrete based on eggshell particles and waste glass powder, characterized in that, The cement uses ordinary Portland cement; the water reducing agent is a polycarboxylic acid type high - efficiency water reducing agent with a water reduction rate of 25%.

7. A method for preparing high-strength green concrete based on eggshell particles and waste glass powder, characterized in that, Specifically, it includes the following steps: Mix and stir 44.6 - 133.8 kg of eggshell particles, 44.6 - 133.8 kg of waste glass powder with 1290 - 1320 kg of coarse aggregate, 555 - 595 kg of fine aggregate, plus 178.4 - 356.8 kg of cement, then plus 111.5 - 133.8 kg of water and 4.46 kg of water reducing agent to finally obtain the target product, high - strength green concrete.

8. A method for preparing high-strength green concrete based on eggshell particles and waste glass powder according to claim 7, characterized in that The method for obtaining the waste glass powder is: sieve and then ball - mill the washed, dried and crushed waste glass to obtain waste glass powder; in the waste glass powder, the proportion of powder particles with a particle size of 15 - 20 μm is ≥ 90%, and the rest are uncompletely crushed coarse particles > 20 μm or overly fine powder < 15 μm.

9. A method for preparing high-strength green concrete based on eggshell particles and waste glass powder according to claim 7, characterized in that, The method for obtaining the eggshell particles is: clean the eggshells, dry them at 60 - 80 °C for 4 - 5 hours, then crush them, remove the residual egg membranes in the crushed eggshells by air - separation or screening, and remove metal impurities by magnetic separation; then, calcine the crushed eggshells at 900 - 950 °C for 4 - 5 hours, and ball - mill the calcined crushed eggshells until the particle size reaches 15 - 20 μm.

10. A high - strength green concrete based on eggshell particles and waste glass powder, prepared from the raw materials of any one of the concretes in claims 1 to 6, or prepared by any one of the methods in claims 7 to 9, and the water - binder ratio of the obtained high - strength green concrete is 0.25 - 0.3.

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