Baking-free brick and preparation method thereof
By mixing waste concrete and steel slag recycled fine aggregate with cement and high-pressure molding to prepare burn-free bricks, the problem of resource utilization of construction waste is solved, high-strength brick preparation is achieved, and large-scale resource utilization of construction waste is realized.
Patent Information
- Application Number
- CN202510279362.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-10
- Publication Date
- 2025-07-08
AI Technical Summary
The prior art is difficult to efficiently and at low cost to utilize construction waste, especially waste concrete and steel slag, which leads to its disposal difficulties and waste of resources.
Use waste concrete regenerated fine aggregate and/or steel slag regenerated fine aggregate to mix with cement, add appropriate amount of water and water reducing agent, prepare burn-free bricks through high-pressure molding, and use construction waste as the main raw material to make up for the defect of insufficient strength of waste concrete fine aggregate.
The high amount of construction waste is used in large quantities and large batches, and the fire-free bricks with a strength of MU20 are prepared, which not only solves the problem of construction waste disposal, but also improves the strength of bricks.
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Abstract
Description
Technical Field
[0001] This application relates to the technical field of construction waste recycling, and particularly relates to a non-fired brick and a preparation method thereof. Background Art
[0002] The resource treatment of construction waste is an important part of the renewable resource industry. Summary of the Invention
[0003] Based on the ways of recycling construction waste and the characteristics of construction waste materials, this application provides a non-fired brick mixture, a non-fired brick and a preparation method thereof using waste concrete or / and steel slag as raw materials, so as to solve the above technical problems and realize the high-ratio and large-batch recycling of construction waste.
[0004] In the first aspect of this application, a non-fired brick is provided, which is composed of the following raw materials in parts by weight: 850-1700 parts of recycled fine aggregate, 125-250 parts of cement, 25-50 parts of waste concrete recycled fine powder, 100-200 parts of water, and 6-12 parts of water reducer. The recycled fine aggregate is waste concrete recycled fine aggregate or / and steel slag recycled fine aggregate.
[0005] Preferably, the particle size d of the waste concrete recycled fine aggregate ranges from 0.08 mm < d ≤ 5 mm, and the apparent density is 2250 kg / m 3 ~2350 kg / m 3 .
[0006] Preferably, the particle size w of the waste concrete recycled fine powder ranges from w ≤ 0.08 mm, and the apparent density is 2600 kg / m 3 ~2700 kg / m 3 .
[0007] Preferably, the particle size g of the steel slag recycled fine aggregate ranges from g ≤ 5 mm, and the apparent density is 3200 kg / m 3 ~3700 kg / m 3 , and the immersion expansion rate is 0.1% - 1.9%.
[0008] In the second aspect of this application, a preparation method of a non-fired brick is provided, which includes the following steps:
[0009] Mixture preparation: Mix and disperse waste concrete recycled fine aggregate or / and steel slag recycled fine aggregate, waste concrete recycled fine powder, and cement, add water and stir, and add water reducer while stirring to obtain a mixture;
[0010] Non-fired brick preparation: Mold, form and cure the mixture in sequence to obtain a non-fired brick.
[0011] Preferably, the preparation steps of the waste concrete recycled fine aggregate and recycled fine powder include: selecting waste concrete from the demolition of building structure walls, subjecting the waste concrete to multi-stage crushing and screening to obtain waste concrete recycled fine aggregate particles and waste concrete recycled fine powder meeting the target particle size.
[0012] Preferably, after obtaining the waste concrete recycled fine aggregate particles meeting the target particle size, pre-wetting treatment is carried out.
[0013] Preferably, the preparation steps of the steel slag recycled fine aggregate include: selecting steel slag after pot-type pressurized heat soaking treatment, crushing and screening the heat-soaked steel slag to obtain steel slag recycled fine aggregate particles meeting the target particle size.
[0014] Preferably, the forming step includes: adopting a one-time pressing forming process, with a forming pressure of 20 Ma, a static pressure loading speed of 10 KN / s, maintaining at least 5 s after the static pressure reaches the forming pressure and then starting to relieve pressure by oil return.
[0015] The beneficial effects of this application are: This application uses waste concrete or / and steel slag as recycled fine aggregate and waste concrete as recycled fine powder to prepare pressed non-fired bricks, enabling effective utilization of construction waste. And the use of steel slag recycled fine aggregate can make up for the deficiency of low strength of waste concrete fine aggregate and improve the strength of non-fired bricks. Specific embodiments
[0016] To make the purpose, technical solutions and advantages of this application clearer, the technical solutions of this application will be clearly and completely described below in conjunction with specific embodiments of this application. Obviously, the described embodiments are only part of the embodiments of this application, rather than all embodiments. Based on the embodiments in this application, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of this application.
[0017] This application uses waste concrete recycled fine aggregate or / and steel slag recycled fine aggregate as aggregate, mixes it with cement, adds an appropriate amount of water and mixes evenly, and then forms it through high-pressure molding and cures it to make non-fired bricks. The non-fired bricks of this application can be used as new wall materials in buildings or paved on the road surface layer. It not only realizes the low-cost disposal of construction waste, but also realizes the high-volume and large-batch resource utilization of construction waste. In addition, the use of steel slag recycled fine aggregate can make up for the deficiency of low strength of waste concrete fine aggregate and improve the strength of non-fired bricks.
[0018] A non-fired brick provided by an embodiment of this application is composed of the following raw materials in parts by weight: 850 - 1700 parts of recycled fine aggregate, 125 - 250 parts of cement, 25 - 50 parts of waste concrete recycled fine powder, 100 - 200 parts of water, and 6 - 12 parts of water reducer, and the recycled fine aggregate is waste concrete recycled fine aggregate or / and steel slag recycled fine aggregate.
[0019] Specifically, the recycled fine aggregate may be all waste concrete recycled fine aggregate, or all steel slag recycled fine aggregate, or a mixture of waste concrete recycled fine aggregate and steel slag recycled fine aggregate.
[0020] In an embodiment provided by the present application, the particle size d of the waste concrete recycled fine aggregate ranges from 0.08 mm < d ≤ 5 mm, and the apparent density is 2250 kg / m 3 ~2350 kg / m 3 。
[0021] In an embodiment provided by the present application, the particle size w of the waste concrete recycled micropowder ranges from w ≤ 0.08 mm, and the apparent density is 2600 kg / m 3 ~2700 kg / m 3 。
[0022] In an embodiment provided by the present application, the particle size g of the steel slag recycled fine aggregate ranges from g ≤ 5 mm, and the apparent density is 3200 kg / m 3 ~3700 kg / m 3 , and the immersion expansion rate is 0.1% - 1.9%.
[0023] The embodiment of the present application also provides a method for preparing non-fired bricks, including the following steps:
[0024] Preparation of the mixture: Mix and disperse the waste concrete recycled fine aggregate or / and steel slag recycled fine aggregate, waste concrete recycled micropowder, and cement, add water and stir, and add a water reducing agent during stirring to obtain a mixture;
[0025] Preparation of non-fired bricks: Mold, shape, and cure the mixture in sequence to obtain non-fired bricks.
[0026] Optionally, the curing conditions are: temperature is 18 - 22 °C, and humidity ≥ 95% RH.
[0027] In an embodiment provided by the present application, the preparation steps of the waste concrete recycled fine aggregate and recycled micropowder include: Select waste concrete from the demolition of building structure walls, crush and screen the waste concrete to obtain waste concrete recycled fine aggregate particles and waste concrete recycled micropowder that meet the target particle size.
[0028] In an embodiment provided by the present application, after obtaining the waste concrete recycled fine aggregate particles that meet the target particle size, pre-wetting treatment is performed.
[0029] In an implementation manner provided by the present application, the preparation steps of the steel slag recycled fine aggregate include: selecting the steel slag after pot-type pressurized thermal soaking treatment, and performing multi-stage crushing and screening on the thermally soaked steel slag to obtain steel slag recycled fine aggregate particles meeting the target particle size.
[0030] In an implementation manner provided by the present application, the forming step includes: adopting a one-time pressing forming process, with a forming pressure of 20 Ma, a static pressure loading speed of 10 KN / s, and maintaining at least 5 s after the static pressure reaches the forming pressure before starting to relieve pressure by oil return.
[0031] Specifically, to avoid damage to the brick blank during demolding, before loading the mold, keep the inner wall of the mold clean, and a thin layer of release agent such as mineral oil can be evenly applied on its inner wall, and the release agent should be evenly distributed without obvious deposition. During the mold loading process, appropriately squeeze and tamp the mixture forcefully, and level the upper surface with a trowel. After the mold loading is completed, cover the pressure plate and perform static pressure forming. Immediately demold after forming and carry out curing.
[0032] In the embodiment of the present application, waste concrete from the demolition of a certain building structure wall is selected, crushed and screened, and the particles with a particle size of 0.08 mm and below are used as waste concrete recycled micropowder for standby, and its apparent density is 2650 kg / m 3 ; the particles with a particle size greater than 0.08 mm and less than or equal to 5 mm are used as waste concrete recycled fine aggregate for standby, and its apparent density is 2287 kg / m 3 .
[0033] In the embodiment of the present application, the steel slag after pot-type pressurized thermal soaking treatment adopted by the iron and steel enterprise is selected, and after crushing, iron selection and screening, steel slag recycled fine aggregate with a particle size of 0 - 5 mm (including 5 mm) is obtained; its apparent density is measured to be 3794 kg / m 3 , and the immersion expansion rate is 0.1%.
[0034] It should be noted that in the expression of the content of the raw material components of the present application, the end point values are all included. For example: 125 - 250 parts of cement, which means: 125 parts ≤ the weight parts of cement ≤ 250 parts.
[0035] The following further elaborates on the present application in combination with specific embodiments.
[0036] Example 1
[0037] The non-fired brick mixture in this example is composed of the following components in parts by weight: 425 parts of waste concrete recycled fine aggregate, 425 parts of steel slag recycled fine aggregate, 125 parts of cement, 25 parts of waste concrete recycled micropowder, 100 parts of water, and 6 parts of water reducing agent.
[0038] Example 2
[0039] The non-fired brick mixture in this embodiment is composed of the following components in parts by weight: 425 parts of recycled fine aggregate of waste concrete, 850 parts of recycled fine aggregate of steel slag, 225 parts of cement, 40 parts of recycled micro-powder of waste concrete, 150 parts of water, and 9 parts of water reducer.
[0040] Example 3
[0041] The non-fired brick mixture in this embodiment is composed of the following components in parts by weight: 425 parts of recycled fine aggregate of waste concrete, 1275 parts of recycled fine aggregate of steel slag, 250 parts of cement, 50 parts of recycled micro-powder of waste concrete, 195 parts of water, and 8 parts of water reducer.
[0042] Example 4
[0043] The non-fired brick mixture in this embodiment is composed of the following components in parts by weight: 850 parts of recycled fine aggregate of waste concrete, 125 parts of cement, 25 parts of recycled micro-powder of waste concrete, 100 parts of water, and 8 parts of water reducer.
[0044] Example 5
[0045] The non-fired brick mixture in this embodiment is composed of the following components in parts by weight: 850 parts of recycled fine aggregate of waste concrete, 425 parts of recycled fine aggregate of steel slag, 225 parts of cement, 40 parts of recycled micro-powder of waste concrete, 150 parts of water, and 8 parts of water reducer.
[0046] Example 6
[0047] The non-fired brick mixture in this embodiment is composed of the following components in parts by weight: 1275 parts of recycled fine aggregate of waste concrete, 425 parts of recycled fine aggregate of steel slag, 250 parts of cement, 50 parts of recycled micro-powder of waste concrete, 195 parts of water, and 12 parts of water reducer.
[0048] Example 7
[0049] The non-fired brick mixture in this embodiment is composed of the following components in parts by weight: 1700 parts of recycled fine aggregate of steel slag, 250 parts of cement, 50 parts of recycled micro-powder of waste concrete, 200 parts of water, and 12 parts of water reducer.
[0050] Furthermore, the components and contents of the above Examples 1 to 7 are summarized in Table 1 below:
[0051] Table 1: Component and Content Table of Examples 1 to 7
[0052]
[0053] Weigh the raw materials according to the above ratios respectively. Mix and disperse the waste concrete recycled fine aggregate, steel slag recycled fine aggregate, waste concrete recycled powder and cement, add water and stir, and add a water reducing agent while stirring to obtain a mixture. Put the mixtures of each example into a mold respectively and adopt a one-time forming process. After static pressure forming, demold and cure to obtain the corresponding non-fired bricks prepared from the mixtures of Examples 1 to 7.
[0054] For the non-fired bricks prepared in Examples 1 to 7, conduct the compressive strength and flexural strength tests at the ages of 7d and 28d one by one. The test results are shown in the strength test results in Table 2.
[0055] It can be understood that the age refers to the time experienced by the mixture since the start of adding water and stirring. 7d means 7 days since the start of adding water and stirring. Under normal curing conditions, the strength of cement or the mixture will continuously develop with the increase of age. The strength develops relatively fast within the first 7 - 14d, and then gradually slows down. The strength reaches the design strength at 28d, and the strength grade is determined according to the 28d compressive strength. The strength is still developing after 28d, and its growth process can continue for decades.
[0056] Table 2 Strength test results
[0057]
[0058] As can be seen from Table 1, the 28-day compressive strength of the non-fired bricks prepared in Examples 1 to 7 is all above 20MPa, and the 28-day flexural strength is all above 3MPa, meeting the strength requirements of the MU20 level. Among them, the compressive strength and flexural strength of Example 7 are the highest, and those of Example 4 are the lowest.
[0059] Of course, the size of the non-fired bricks prepared according to the present application is not limited to the size of 240mm * 115mm * 53mm listed in the examples of the present application, and its shape is not limited to a cuboid either. Bricks with the required shape and size can be prepared according to the construction needs, and the present application does not make any limitations here.
[0060] In the mixture of the non-fired bricks of the present application, the recycled fine aggregate can be all waste concrete recycled fine aggregate, or all steel slag recycled fine aggregate, or a mixture of waste concrete recycled fine aggregate and steel slag recycled fine aggregate. That is, it can be flexibly selected according to the type of waste materials, and the proportion can be adjusted in a timely manner according to the amount of waste building materials or waste steel slag available during construction to achieve the reasonable recycling of waste.
[0061] The above are only the embodiments of the present application and are not used to limit the present application. For those skilled in the art, various changes and modifications can be made to the present application. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present application shall be included within the scope of the claims of the present application.
Claims
1. A non-fired brick, characterized in that, It is composed of the following raw materials in parts by weight: 850 - 1700 parts of recycled fine aggregate, 125 - 250 parts of cement, 25 - 50 parts of recycled waste concrete micropowder, 100 - 200 parts of water, and 6 - 12 parts of water reducer. The recycled fine aggregate is recycled fine aggregate of waste concrete or / and recycled fine aggregate of steel slag.
2. The unfired brick according to claim 1, characterized in that, The range of the particle size d of the recycled fine aggregate of waste concrete is 0.08 mm < d ≤ 5 mm, and the apparent density is 2250 kg / m 3 ~2350 kg / m 3 .
3. The unfired brick according to claim 1, characterized in that, The particle size w of the recycled waste concrete micro-powder ranges from w ≤ 0.08 mm, and the apparent density is 2600 kg / m 3 ~2700 kg / m 3 .
4. A non-burned brick according to claim 1, characterized in that, The range of the particle size g of the recycled fine steel slag aggregate is g ≤ 5 mm, and the apparent density is 3200 kg / m 3 ~3700 kg / m 3 , and the immersion expansion rate is 0.1% - 1.9%.
5. A method for preparing non-fired bricks, characterized in that, It includes the following steps: Preparation of the mixture: Mix and disperse the recycled fine aggregate of waste concrete or / and recycled fine aggregate of steel slag, recycled waste concrete micropowder, and cement, add water and stir, and add the water reducer while stirring to obtain the mixture. Preparation of non - fired bricks: Mold, form, and cure the mixture in sequence to obtain non - fired bricks.
6. The preparation method of the non-fired brick according to claim 5, characterized in that, The preparation steps of the recycled fine aggregate and recycled micropowder of waste concrete include: Select the waste concrete from the demolition of building structure walls, crush and screen the waste concrete to obtain the recycled fine aggregate particles of waste concrete and recycled waste concrete micropowder that meet the target particle size.
7. A method for preparing non-fired bricks according to claim 6, characterized in that, After obtaining the recycled fine aggregate particles of waste concrete that meet the target particle size, carry out pre - wetting treatment.
8. A method for preparing non-fired bricks according to claim 5, characterized in that, The preparation steps of the recycled fine aggregate of steel slag include: Select the steel slag after pot - type pressure heat - smothering treatment, crush and screen the heat - smothered steel slag to obtain the recycled fine aggregate particles of steel slag that meet the target particle size.
9. A method for preparing non-fired bricks according to claim 5, characterized in that, The forming step includes: Adopt a one - time pressing forming process, the forming pressure is 20 Ma, the static pressure loading speed is 10 KN / s, and after the static pressure reaches the forming pressure, maintain it for at least 5 s and then start to relieve the pressure by oil return.
10. A method for preparing non-fired bricks according to claim 5, characterized in that, The temperature is 18 - 22 °C, and the curing humidity ≥ 95% RH.