Method for preparing thermally activated slag, cement and calcium hydroxide mixture geopolymer concrete and prefabricated bay window

Abstract

The application provides a preparation method of thermally activated slag, cement and calcium hydroxide mixture geopolymer concrete, which comprises the following steps: a, raw material preparation; b, raw material pretreatment; c, activity excitation; d, net paste preparation; and e, concrete configuration. The application also provides a prefabricated bay window, and the main material of the prefabricated bay window is the thermally activated slag, cement and calcium hydroxide mixture geopolymer concrete prepared by the preparation method. The preparation method of the thermally activated slag, cement and calcium hydroxide mixture geopolymer concrete uses the slag obtained in the earthwork excavation of a project as the main material of the concrete, significantly reduces the dependence on the traditional concrete raw materials, reduces the energy consumption and greenhouse gas emission in the raw material mining process, and effectively alleviates the global greenhouse effect. In addition, the construction cost is saved, the transportation and treatment cost of the construction slag is greatly reduced, and remarkable economic benefits are brought to enterprises.

Description

TECHNICAL FIELD

[0002] The present application relates to the technical field of building materials, in particular to a preparation method of a hot-activated slag, cement and calcium hydroxide mixture geopolymer concrete, and a prefabricated bay window of the hot-activated slag, cement and calcium hydroxide mixture geopolymer concrete prepared by using the preparation method. BACKGROUND

[0004] In the traditional concrete manufacturing process, not only a large amount of natural resources such as sand and stone aggregates are relied on, but also the energy consumption and environmental pollution problems in the production process are criticized. Especially in the cement production process, data shows that about 1.5 tons of limestone and a large amount of coal and electric energy are needed to produce 1 ton of Portland cement, and a large amount of carbon dioxide is also emitted. Studies have shown that the greenhouse gas emissions from cement production account for a considerable proportion of the total human emissions, exacerbating the global greenhouse effect. In addition, the raw materials of traditional concrete mainly come from natural resources such as sand and stone aggregates. The exploitation of these resources not only consumes a large amount of energy, but also may cause resource depletion and ecological damage. With the increasing use of concrete, the demand for raw materials such as sand and stone is also rising, and some areas have already experienced a shortage of sand and stone resources and ecological damage.

[0005] In addition, with the acceleration of urbanization, the amount of slag produced by construction engineering is increasing, which has brought a heavy burden to the environment. SUMMARY

[0007] The purpose of the present application is to provide a preparation method of a hot-activated slag, cement and calcium hydroxide mixture geopolymer concrete, which can utilize construction slag and other waste as raw materials, reduce the dependence on traditional raw materials, reduce energy consumption and emissions in the production process, and reduce environmental pollution, aiming to solve the above-mentioned problems existing in the concrete manufacturing of the prior art.

[0008] The present application is realized by the following technical solutions:

[0009] The preparation method of the hot-activated slag, cement and calcium hydroxide mixture geopolymer concrete comprises the following steps:

[0010] a. Raw material preparation: obtaining slag from project earthwork excavation;

[0011] b. Raw material pretreatment: drying and screening the slag in step a to obtain dry slag powder and slag particles with suitable particle size;

[0012] c. Activity excitation: adding ordinary cement and alkali activator to mix with the slag powder and the slag particles in step b, and performing calcination treatment under high temperature conditions to obtain an activated mixture;

[0013] d. Net paste preparation: mixing the activated mixture of step c with alkaline solution and water to prepare a net paste material;

[0014] e. Concrete configuration: mixing the net paste material of step d with coarse aggregate, fine aggregate and admixture to obtain a hot activated slag, cement and calcium hydroxide mixture geopolymer concrete paste.

[0015] The working principle of the present application is mainly based on the formation mechanism of geopolymer concrete. Geopolymer concrete is a new type of concrete formed by activating the activity of industrial waste or natural minerals with an alkali activator, and then chemically reacting with cement and other materials. In the present application, the slag obtained from the project earthwork excavation is pretreated to obtain dry slag powder and slag particles with suitable particle size. Then ordinary cement, alkali activator and slag powder and slag particles are mixed, and calcination treatment is carried out under high temperature conditions to activate the activity of the slag. Under the action of the alkali activator, the silicate and aluminate minerals in the slag undergo dissolution and polycondensation reaction to form a geopolymer gel with a three-dimensional network structure. This gel has high strength and adhesion, which can significantly improve the performance of the concrete. Finally, the activated mixture is mixed with an alkaline solution and water in a certain proportion to prepare a net paste material, and is mixed and stirred with coarse aggregate, fine aggregate and admixture to obtain a hot activated slag, cement and calcium hydroxide mixture geopolymer concrete.

[0016] The present application uses slag obtained from project earthwork excavation as the main raw material, which significantly reduces the dependence on traditional concrete raw materials such as sand and stone aggregate. This not only reduces the energy consumption in the process of raw material mining, but also reduces the emission of related greenhouse gases such as carbon dioxide, thereby effectively alleviating the global greenhouse effect.

[0017] By high-temperature calcination treatment to activate the activity of the slag, the reasonable secondary use of industrial waste resources (i.e. slag) is realized, which promotes the recycling of resources. This not only helps to alleviate the problem of resource shortage, but also reduces the overexploitation of natural resources, in line with the concept of sustainable development.

[0018] In addition, compared with traditional cement production, this method produces less waste during production, and the environmental performance can be further optimized by adjusting the formula and process parameters. In addition, due to the reduction of sand and stone and other raw materials, the damage to the ecological environment is also reduced.

[0019] Through the preparation process proposed by the present application, the hot activated slag, cement and calcium hydroxide mixture geopolymer concrete obtained by the present application not only has the mechanical properties of traditional concrete, but also saves construction cost, greatly reduces the transportation and treatment cost of construction slag, and brings significant economic benefits to the enterprise.

[0020] Preferably, in the present application, the drying temperature in step b is 100-110°C, the drying time is 24 hours, the particle size of the slag particles is less than or equal to 1.5 mm and greater than or equal to 4.75 mm.

[0021] By drying to ensure that the slag is fully dried, free water and part of the bound water are removed, thereby improving the quality and stability of the subsequent concrete preparation, at the same time, this drying condition is also standardized, which is convenient for accurate control in actual operation, and the particle size range of the slag particles helps to improve the compactness and workability of the concrete. Specifically, small particles can fill the voids between large particles, improving the compactness of the concrete; while large particles can provide better aggregate framework, enhancing the mechanical properties of the concrete.

[0022] Preferably, in the present application, the high-temperature condition in step c is 700-750°C, the calcination time is 2 hours, and the particle size of the slag particles is less than or equal to 1.5 mm.

[0023] High-temperature calcination can effectively activate the slag, causing phase transition and activation of silicate minerals in it, thereby improving the reactivity with cement and other materials. This helps to form a more stable and superior performance geopolymer gel in the subsequent steps. The use of slag particles with a particle size of less than or equal to 1.5 mm in step c helps to improve the calcination effect and the performance of the subsequent concrete, because small particle size slag particles have a larger specific surface area, which can more fully contact and react with the alkali activator, thereby increasing the amount and quality of the geopolymer gel. In addition, high-temperature calcination can be carried out in a muffle furnace to ensure the uniformity and stability of the calcination process. The muffle furnace has good temperature control and adjustment ability, which can provide a constant calcination environment, thereby ensuring the uniform activation of the slag particles and the generation of high-quality geopolymer gel.

[0024] Preferably, in the present application, the alkali solution in step d is a sodium carbonate solution prepared by dissolving sodium carbonate and water in advance, and the addition amount is preferably 7%-9% based on the total weight percentage of the liquid activator and the solid raw material.

[0025] The sodium carbonate solution can promote the dissolution and polycondensation of silicate minerals in the slag to form a geopolymer gel, thereby improving the strength and durability of the concrete, helping to ensure the sufficiency and moderation of the alkali activation process, avoiding the decline of the concrete performance caused by excessive or insufficient amount, maximizing the activation of the slag, and improving the generation efficiency and quality of the geopolymer gel.

[0026] Preferably, in the present application, the water-to-solid ratio in step e is preferably 25%-32%.

[0027] When the water-solid ratio is 25% to 32%, the water in the concrete can fully meet the needs of the cement hydration reaction, and at the same time, it will not cause too many pores, which makes the concrete maintain good working performance while achieving the highest strength and durability.

[0028] Preferably, in the present application, the weight mix proportion of the thermally activated slag-cement-hydroxide mixture geopolymer concrete in step e is activated mixture: sodium carbonate: fine aggregate: coarse aggregate: water = 1: 0.2 to 0.4: 1.5 to 1.7: 1.2 to 1.4: 0.1 to 0.2, the coarse aggregate is preferably the slag particles with a particle size greater than or equal to 4.75 mm, and the fine aggregate is preferably the medium sand with a particle size of 1.0 mm to 2.0 mm.

[0029] By specifying the specific mix proportion, it can be ensured that the thermally activated slag-cement-hydroxide mixture geopolymer concrete prepared each time has consistent performance, thereby improving the stability and reliability of the concrete. Using slag particles with a particle size greater than or equal to 4.75 mm as coarse aggregate and medium sand with a particle size of 1.0 mm to 2.0 mm as fine aggregate can optimize the aggregate framework of the concrete. The coarse aggregate provides the main skeleton support, while the fine aggregate fills the gaps between the coarse aggregate, together forming a compact internal structure of the concrete, thereby enhancing the structural strength of the concrete.

[0030] Preferably, in the present application, the alkali activator in step c is calcium hydroxide.

[0031] During the high-temperature calcination process in step c, calcium hydroxide as a strong alkaline activator can promote the thermal-chemical transformation of active ingredients such as silicate and aluminate in the slag. This transformation includes the decomposition of minerals, the generation of active silicon aluminum oxides, etc., thereby significantly improving the reactivity of the slag. Under the combined action of high temperature and calcium hydroxide, the generation of geopolymer gel can be promoted. Specifically, during high-temperature calcination, calcium hydroxide reacts with active silicon aluminum oxides in the slag to generate precursors of geopolymer gel, which will further react in the subsequent concrete preparation process, such as when mixed with an alkaline solution (sodium carbonate solution) in step d, it can participate in the reaction more quickly and completely, thereby generating more geopolymer gel, which helps to improve the strength and durability of the neat paste material.

[0032] In addition, the high-temperature calcination process in step c not only activates the slag, but also changes its microstructure, such as reducing porosity and making the particle surface more rough. These changes facilitate the penetration of the alkaline solution (sodium carbonate solution) into the interior of the activated mixture in step d, allowing it to fully contact and react with the active ingredients therein, thereby generating a more uniform and dense geopolymer gel network. It should be noted that the activated mixture generated in step c can rapidly hydrate with water and alkali ions in the solution after mixing with the alkaline solution (sodium carbonate solution) in step d, generating a large amount of hydration products. These hydration products fill the pores of the neat paste material, further improving its density and strength.

[0033] Preferably, in the present application, the admixture includes S105 grade ground granulated blast furnace slag and F-class fly ash, the particle size of the F-class fly ash is less than 45 μm, the specific surface area is 400 m² / kg~450 m² / kg, and the dosage range is 12~15%; the particle size of the S105 grade ground granulated blast furnace slag is less than 45 μm, the specific surface area is 500 m² / kg~520 m² / kg, and the dosage range is 10~13%.

[0034] The fineness and high specific surface area of blast furnace slag help it better combine with other ingredients in concrete, forming a more robust structure. It should be noted that particle size and specific surface area are key factors affecting the effectiveness of the admixture, and smaller particle size and larger specific surface area mean more particle surfaces can react with other ingredients, thereby improving the efficiency and extent of the reaction.

[0035] The active ingredients (such as silicon dioxide, aluminum oxide, etc.) in F-class fly ash and blast furnace slag can react with ingredients such as calcium hydroxide in concrete in an alkaline environment to generate hydration products (such as hydrated calcium silicate, hydrated calcium aluminate, etc.) with cementitious properties, which can fill the voids in concrete and form a robust network structure, thereby improving the performance of concrete.

[0036] The present application also provides a prefabricated bay window, comprising a bay window body, the bay window body is uniformly provided with a CFRP connecting rib on one side, which is fixed with the building structure, and the material of the bay window body is the hot-activated slag, cement and calcium hydroxide mixture geopolymer concrete prepared by the above preparation method.

[0037] Compared with the prior art, the present application has the following advantages:

[0038] 1. The preparation method of the thermally activated slag, cement and calcium hydroxide mixture geopolymer concrete provided by the present application significantly reduces the dependence on traditional concrete raw materials (such as cement, sand, stone aggregate), reduces the energy consumption and greenhouse gas emissions in the raw material mining process, thereby effectively alleviating the global greenhouse effect. This advantage is mainly achieved by using the slag obtained from the earthwork excavation of the project as the main raw material, which not only solves the problem of construction slag disposal, but also reduces the exploitation of natural resources.

[0039] 2. The present application activates the slag by high-temperature calcination treatment, realizes the reasonable secondary use of industrial waste resources (i.e. slag), and promotes the recycling of resources, which not only helps to alleviate the resource shortage problem, but also reduces the over-exploitation of natural resources, in line with the concept of sustainable development.

[0040] 3. The thermally activated slag, cement and calcium hydroxide mixture geopolymer concrete prepared by the preparation process of the present application not only has the mechanical properties of traditional concrete, but also saves the construction cost, greatly reduces the transportation and disposal cost of construction slag, and brings significant economic benefits to the enterprise. This advantage is mainly achieved by using the slag as a raw material which was originally waste, and optimizing the preparation process.

[0041] 4. By optimizing the process parameters such as drying temperature, drying time, slag particle size, high-temperature calcination conditions, selection and addition amount of alkaline solution, water-solid ratio and specific mix proportion, the present application can prepare thermally activated slag, cement and calcium hydroxide mixture geopolymer concrete with excellent performance. These optimized process parameters help to improve the strength, durability and workability of the concrete.

[0042] 5. The present application also provides the application of the prepared thermally activated slag, cement and calcium hydroxide mixture geopolymer concrete in the manufacture of prefabricated bay windows, which further expands the application field of the thermally activated slag, cement and calcium hydroxide mixture geopolymer concrete and improves its market value. Through the fixation of CFRP connecting bars and building structures, the structural stability and safety of prefabricated bay windows are enhanced.

DRAWINGS

[0044] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed in the embodiment description will be briefly introduced as follows.

[0045] Figure 1 The preparation flowchart of embodiments 1-3 of the present application;

[0046] Figure 2 The structure schematic diagram of embodiment 4 of the present application;

[0047] Figure 3This is an analysis diagram of the precast bay window concrete Mise of Embodiment 4 of the present invention;

[0048] Figure 4 This is an analysis diagram of the CFRP steel reinforcement of the precast bay window in Embodiment 4 of the present invention.

Detailed Implementation Methods

[0050] To make the technical problems solved by this application, the technical solutions, and the beneficial effects clearer, this application will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of this application and are not intended to limit this application.

[0051] Example 1

[0052] This embodiment provides a polymer concrete made from a mixture of thermally activated slag, cement, and calcium hydroxide. By weight, the ratio of activated mixture: sodium carbonate: fine aggregate: coarse aggregate: water = 1:0.3:1.5:1.2:0.1.

[0053] The activated mixture includes slag particles with a particle size of less than or equal to 1.5 mm, slag powder, ordinary cement, and calcium hydroxide; the fine aggregate is medium sand with a particle size of 1.8 mm, and the coarse aggregate is slag particles with a particle size of greater than or equal to 4.75 mm.

[0054] The preparation method includes the following steps:

[0055] a. Raw material preparation: Obtain excavated soil from the project's earthwork excavation;

[0056] b. Raw material pretreatment: The slag soil mentioned in step a is dried and screened in an oven at a temperature of 100~110°C for 24 hours to obtain dry slag soil powder and slag soil particles of suitable particle size. The slag soil particles include two specifications: particle size less than or equal to 1.5mm and greater than or equal to 4.75mm.

[0057] c. Activation: Add ordinary cement, calcium hydroxide, and the slag powder and slag particles with a particle size of less than or equal to 1.5 mm as described in step b, mix them, and calcine them in a muffle furnace at 700~750°C for 2 hours to obtain an activated mixture;

[0058] d. Preparation of paste: The activated mixture described in step c is mixed with sodium carbonate solution and water to prepare paste material;

[0059] e. Concrete preparation: the net paste material of step d is mixed with coarse aggregate (slag particles with particle size greater than or equal to 4.75 mm), fine aggregate (medium sand with particle size 1.8 mm) and admixture (F-class fly ash with dosage 12%, S105-grade ground granulated blast furnace slag with dosage 13%), to obtain the hot-activated slag, cement and calcium hydroxide mixture geopolymer concrete slurry.

[0060] After the hot-activated slag, cement and calcium hydroxide mixture geopolymer concrete is prepared, the hot-activated slag, cement and calcium hydroxide mixture geopolymer concrete slurry is poured into a mold (150 mm x 150 mm x 150 mm cubic mold, a total of 12 molds are poured), a vibration table and manual insertion are used to compact it to density, and after leveling, a plastic film is covered for 28 days of curing.

[0061] Example 2

[0062] The present embodiment provides a hot-activated slag, cement and calcium hydroxide mixture geopolymer concrete, in which the weight mixing ratio of the activated mixture: sodium carbonate: fine aggregate: coarse aggregate: water is 1:0.2:1.6:1.3:0.2.

[0063] The activated mixture includes slag particles with particle size less than or equal to 1.5 mm, slag powder, ordinary cement and calcium hydroxide; the fine aggregate is medium sand with particle size 1.8 mm, and the coarse aggregate is slag particles with particle size greater than or equal to 4.75 mm.

[0064] The preparation method includes the following steps:

[0065] a. Raw material preparation: obtain slag from project earthwork excavation;

[0066] b. Raw material pretreatment: dry and sieve the slag of step a using an oven, the drying temperature is 100-110°C, and the drying time is 24 hours, to obtain dry slag powder and slag particles with suitable particle size, the slag particles include two specifications with particle size less than or equal to 1.5 mm and greater than or equal to 4.75 mm;

[0067] c. Activity excitation: mix ordinary cement, calcium hydroxide and the slag powder and slag particles with particle size less than or equal to 1.5 mm of step b, and put them into a muffle furnace for calcination at 700-750°C for 2 hours, to obtain an activated mixture;

[0068] d. Net paste preparation: mix the activated mixture of step c with sodium carbonate solution and water to prepare a net paste material;

[0069] e. Concrete preparation: the net paste material of step d is mixed with coarse aggregate (slag particles with particle size greater than or equal to 4.75 mm), fine aggregate (medium sand with particle size 1.8 mm) and admixture (F-class fly ash with dosage 15%, S105-grade ground granulated blast furnace slag with dosage 12%) to obtain the hot-activated slag, cement and calcium hydroxide mixture geopolymer concrete slurry.

[0070] After the hot-activated slag, cement and calcium hydroxide mixture geopolymer concrete is prepared, the hot-activated slag, cement and calcium hydroxide mixture geopolymer concrete slurry is poured into a mold (150 mm x 150 mm x 150 mm cubic mold, a total of 12 molds are poured), a vibration table and manual insertion are used to compact it to density, and after leveling, a plastic film is covered for 28 days of curing.

[0071] Example 3

[0072] The present embodiment provides a hot-activated slag, cement and calcium hydroxide mixture geopolymer concrete. In terms of weight mixing ratio, the activated mixture: sodium carbonate: fine aggregate: coarse aggregate: water = 1:0.4:1.6:1.3:0.2.

[0073] The activated mixture includes slag particles with particle size less than or equal to 1.5 mm, slag powder, ordinary cement, and calcium hydroxide; the fine aggregate is medium sand with particle size 1.8 mm, and the coarse aggregate is slag particles with particle size greater than or equal to 4.75 mm.

[0074] The preparation method includes the following steps:

[0075] a. Raw material preparation: obtain slag from project earthwork excavation;

[0076] b. Raw material pretreatment: dry and sieve the slag of step a using an oven, the drying temperature is 100-110°C, and the drying time is 24 hours, to obtain dry slag powder and slag particles with suitable particle size, the slag particles include two specifications with particle size less than or equal to 1.5 mm and greater than or equal to 4.75 mm;

[0077] c. Activity excitation: add ordinary cement, calcium hydroxide, and the slag powder and slag particles with particle size less than or equal to 1.5 mm of step b, mix and put into a muffle furnace to calcine at 700-750°C for 2 hours to obtain an activated mixture;

[0078] d. Net paste preparation: mix the activated mixture of step c with sodium carbonate solution and water to prepare a net paste material;

[0079] e. Concrete configuration: the net slurry material of step d is mixed with coarse aggregate (slag particles with a particle size greater than or equal to 4.75 mm), fine aggregate (medium sand with a particle size of 1.8 mm), and admixture (14% of F-class fly ash and 10% of S105-grade ground granulated blast furnace slag), to obtain a hot-activated slag, cement and calcium hydroxide mixture geopolymer concrete slurry.

[0080] After the hot-activated slag, cement and calcium hydroxide mixture geopolymer concrete is prepared, the hot-activated slag, cement and calcium hydroxide mixture geopolymer concrete slurry is poured into a mold (150mm x 150mm x 150mm cubic mold, a total of 12 molds are poured), a vibration table and manual insertion are used to compact it to a dense state, and then a plastic film is covered for 28 days of curing.

[0081] Performance test: the hot-activated slag, cement and calcium hydroxide mixture geopolymer concrete prepared in examples 1-3 is used to determine the setting time of the concrete slurry according to the "Standard Test Methods for Properties of Ordinary Concrete Mixtures" (GB / T 50080-2016), and the 7d and 28d compressive strengths of the concrete are tested according to the "Standard Test Methods for Mechanical Properties of Ordinary Concrete" (GB / T 50081-2019). The test results are shown in Table 1.

[0082] Table 1 Performance test results of hot-activated slag, cement and calcium hydroxide mixture geopolymer concrete

[0083]

[0084] As shown in Table 1, the 7d average compressive strength of examples 1-3 can reach up to 22.3MPa, and the 28d average compressive strength can reach up to 31.9MPa, with excellent mechanical properties. The project waste slag can be used as the main raw material of concrete to meet the national standard, and can be used as ordinary concrete in most engineering projects, which can significantly reduce the dependence on traditional concrete raw materials (such as sand and stone aggregate). Not only reduces the energy consumption in the process of raw material mining, but also reduces the emission of related greenhouse gases (such as carbon dioxide), thereby effectively alleviating the global greenhouse effect, achieving the reasonable secondary use of industrial waste resources (i.e. slag), promoting the recycling of resources, saving construction costs, greatly reducing the transportation and disposal costs of construction slag, and bringing significant economic benefits to enterprises.

[0085] Embodiment 4 provides a prefabricated bay window, comprising a bay window body 1, which is uniformly provided with CFRP connecting bars 2 on one side for fixing with a building structure, and the material of the bay window body 1 is the thermally activated slag, cement and calcium hydroxide mixture geopolymer concrete prepared by the preparation method of the thermally activated slag, cement and calcium hydroxide mixture geopolymer concrete as proposed in embodiments 1-3. In specific production, the thermally activated slag, cement and calcium hydroxide mixture geopolymer concrete proposed in the application is poured into a mold of the prefabricated bay window, and is subjected to processes such as vibration and troweling to be shaped. The prefabricated bay window after shaping can be cured at normal temperature or carbonized. Curing at normal temperature means that the concrete is gradually hardened in a natural environment; carbonized curing can accelerate the carbonization reaction of the concrete and improve its strength and durability by using a special carbonized curing box. In addition, carbonized curing not only helps to reduce carbon emissions and save energy, but also realizes the recycling of resources and reduces waste.

[0086] Using the thermally activated slag, cement and calcium hydroxide mixture geopolymer concrete proposed in the application as the material of the bay window body can not only achieve the compressive strength, durability and fireproof performance of traditional concrete. In the manufacturing process, industrial waste and construction waste are fully utilized to realize the recycling of resources and the protection of the environment. Using CFRP connecting bars as the connecting method of the bay window and the building structure can greatly enhance the reliability and stability of the connection. CFRP material has high strength and corrosion resistance, which can effectively resist the erosion and damage of the external environment, ensuring that the bay window remains stable and safe during long-term use. In addition, CFRP material also has good recyclability, meets the requirements of sustainable development, and is convenient for the production and construction of prefabricated components.

[0087] The embodiment can simulate and analyze the use of the prefabricated bay window using thermally activated slag, cement and calcium hydroxide mixture geopolymer concrete as the main material on the building structure by using finite element analysis software abaqus, as shown in Figures 3 to 4 , the Mise analysis of the prefabricated bay window concrete proposed in the embodiment is Figure 3 , and the Mise analysis of the prefabricated bay window CFRP steel bar is Figure 4 . As can be seen from the figure, the overall strength of the thermally activated slag, cement and calcium hydroxide mixture geopolymer concrete prefabricated bay window is equivalent to that of C30 concrete, and the application and popularization of the thermally activated slag, cement and calcium hydroxide mixture geopolymer concrete component can be realized.

[0088] The above is an embodiment provided in combination with specific content, and it is not intended that the specific implementation of the application is limited to these descriptions. Any approximation to the method structure of the application or technical deduction or replacement made on the premise of the concept of the application should be considered as the protection scope of the application.

Claims

1. Process for the production of thermally activated geopolymer concrete from a mixture of slag, cement and calcium hydroxide, characterized in that: It comprises the following steps: a. Raw material preparation: obtaining slag from project earthwork excavation; b. Raw material pretreatment: drying and screening the slag of step a to obtain dry slag powder and slag particles of suitable particle size; c. Activation: mixing ordinary cement, alkali activator, slag powder and slag particles of step b, and calcining under high temperature conditions to obtain an activated mixture; d. Preparation of neat paste: mixing the activated mixture of step c with an alkaline solution and water to prepare a neat paste material; e. Concrete configuration: mixing and stirring the neat paste material of step d with coarse aggregate, fine aggregate and admixture to obtain slag polymer concrete paste; The high temperature condition of step c is 700-750℃, the calcination time is 2 hours, and the particle size of the slag particles is less than or equal to 1.5mm; The alkaline solution of step d is a sodium carbonate solution prepared by dissolving sodium carbonate and water in advance, and the addition amount is controlled between 7% and 9% based on the total weight percentage of liquid activator and solid raw material; The alkali activator in step c is calcium hydroxide; The admixture includes S105 grade ground granulated blast furnace slag and F class fly ash, the particle size of the F class fly ash is less than 45μm, the specific surface area is 400m² / kg-450m² / kg, and the dosage range is 12-15%; the particle size of the S105 grade ground granulated blast furnace slag is less than 45μm, the specific surface area is 500m² / kg-520m² / kg, and the dosage range is 10-13%.

2. The method of preparing a thermally activated slag, cement and calcium hydroxide mixture geopolymer concrete according to claim 1, characterized in that, The drying temperature of step b is 100-110℃, and the drying time is 24 hours.

3. The method of preparing a thermally activated, slag, cement and calcium hydroxide mixture geopolymer concrete according to claim 1, characterized in that, The water-solid ratio in the mixing process of step e is 25%-32%.

4. The method of preparing a thermally activated, slag, cement and calcium hydroxide mixture geopolymer concrete according to claim 1, characterized in that, The coarse aggregate is the slag particles with a particle size greater than or equal to 4.75mm, and the fine aggregate is medium sand with a particle size of 1.0mm-2.0mm.

5. A prefabricated bay window, characterized by It comprises a bay window body (1) uniformly provided with a CFRP connecting tendon (2) fixed to the building structure on one side, and the material of the bay window body (1) is a hot-activated slag, cement and calcium hydroxide mixture geopolymer concrete prepared by the preparation method of any one of claims 1-4.

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