阅读说明：本技术 利用沙漠沙制备的蒸压加气混凝土板及其制备方法 (Autoclaved aerated concrete slab prepared from desert sand and preparation method thereof ) 是由 慎旭双 陈佳佳 戢文占 李俊 刘凯之 王星松 孙通 刘表 陈新喜 李赟 郭志鑫 于 2019-09-26 设计创作，主要内容包括：本发明提供了一种利用沙漠沙制备的蒸压加气混凝土板及其制备方法,包括以下重量份数的组分形成的组合料：沙漠沙55～65份,水泥15～30份,生石灰4～12份,熟石灰3～10份,石膏3～9份,铝粉1～5份,稳泡剂0.5～1份,高岭土0.5～1份,膨润土0.5～1份,所述组合料与水的重量比为1：0.57～0.63。本发明利用沙漠沙替代石英砂或普通天然砂作为硅质材料,制备的蒸压加气混凝土既能够满足建筑材料的要求,又可大幅降低施工成本,保护生态环境,尤其对沙漠化地域更加具有明显的优势,具有广阔的市场前景。(The invention provides an autoclaved aerated concrete slab prepared by using desert sand and a preparation method thereof, wherein the autoclaved aerated concrete slab comprises a composite material formed by the following components in parts by weight: 55-65 parts of desert sand, 15-30 parts of cement, 4-12 parts of quick lime, 3-10 parts of slaked lime, 3-9 parts of gypsum, 1-5 parts of aluminum powder, 0.5-1 part of foam stabilizer, 0.5-1 part of kaolin and 0.5-1 part of bentonite, wherein the weight ratio of the combined material to water is 1: 0.57 to 0.63. According to the invention, the desert sand is used for replacing quartz sand or common natural sand as a siliceous material, and the prepared autoclaved aerated concrete can meet the requirements of building materials, can greatly reduce the construction cost and protect the ecological environment, has more obvious advantages particularly for desertification regions, and has wide market prospects.)

1. An autoclaved aerated concrete slab prepared from desert sand is characterized by comprising a composite material formed by the following components in parts by weight: 55-65 parts of desert sand, 15-30 parts of cement, 4-12 parts of quick lime, 3-10 parts of slaked lime, 3-9 parts of gypsum, 1-5 parts of aluminum powder, 0.5-1 part of foam stabilizer, 0.5-1 part of kaolin and 0.5-1 part of bentonite, wherein the weight ratio of the combined material to water is 1: 0.57 to 0.63.

2. The autoclaved aerated concrete panel prepared from desert sand as claimed in claim 1, wherein the desert sand has a silica content of not less than 65% and a mud content of not more than 2%.

3. The autoclaved aerated concrete panel prepared from desert sand as claimed in claim 1, wherein the cement is ordinary portland cement with a strength grade of not less than 42.5.

4. The autoclaved aerated concrete panel prepared by using desert sand as claimed in claim 1, wherein the foam stabilizer is any one of calcium stearate, gleditsia sinensis lam powder and naphthalene saponin.

5. The autoclaved aerated concrete panel prepared by using desert sand as claimed in claim 1, wherein a reinforcing mesh is further arranged in the concrete panel.

6. A method of making an autoclaved aerated concrete panel according to any of claims 1 to 5, comprising the steps of:

s1: placing all raw materials at the ambient temperature of 35-45 ℃ for more than 24 h;

s2: weighing the desert sand, the cement, the quicklime, the hydrated lime, the gypsum, the kaolin and the bentonite in parts by weight, adding water and stirring;

s3: adding aluminum powder and a foam stabilizer of corresponding components, and stirring to obtain slurry;

s4: and (4) providing a mould for preparing the autoclaved aerated concrete slab, pouring the slurry obtained in the step S3 into the mould, and standing and maintaining for 2-3 hours in an environment at 40-60 ℃ after pouring.

7. The preparation method of the autoclaved aerated concrete panel according to claim 6, wherein in the step S3, the stirring environment temperature is 35-45 ℃, the stirring speed is 150-200 r/min, and the stirring time is 1-3 h.

8. The method for preparing an autoclaved aerated concrete panel according to claim 6, further comprising processing a reinforcing mesh and placing the processed reinforcing mesh in a mold for standby.

9. The method for preparing an autoclaved aerated concrete panel according to claim 6, further comprising: and after standing and curing, removing the die, cutting and milling the groove to obtain a plate blank, and performing autoclaved curing on the plate blank at the curing temperature of 150-200 ℃.

Technical Field

The invention relates to the technical field of building construction, in particular to an autoclaved aerated concrete slab prepared by utilizing desert sand and a preparation method thereof.

Background

The autoclaved aerated concrete slab has the advantages of high strength, low volume weight, heat preservation, sound insulation, fire resistance and the like, can be used for building structure outer walls and inner partition walls, and is the development direction of wallboard materials in China. Compared with the traditional aerated concrete building block, the autoclaved aerated concrete slab can improve the integrity of a building and improve the construction efficiency and the engineering quality. China is vigorously popularizing building industrialization, particularly an assembled concrete structure and an assembled steel structure system, and the characteristics of the autoclaved aerated concrete slab meet the requirements of building industrialization and have popularization value.

At present, quartz sand, river sand and the like are generally adopted for autoclaved aerated concrete slabs, the use of the quartz sand and the river sand damages natural resources to a certain extent, the exploitation of the river sand is strictly forbidden in China, the cost of the quartz sand is high, and the plate price is relatively high. The area of desertification region in China is more than 18% of the area of the national soil, if the desert sand is used for producing building materials, not only can the natural resources be protected from being damaged, but also the cost of the materials can be reduced, and simultaneously, the ecological benefit and the economic benefit are realized.

Disclosure of Invention

In view of the above situation, the invention provides the autoclaved aerated concrete slab prepared by using the desert sand and the preparation method thereof, which can effectively utilize natural resources and save cost, and solves the defects that the existing autoclaved aerated concrete slab is high in cost and the natural resources are damaged to a certain extent due to the adoption of materials.

In order to achieve the purpose, the invention adopts the technical scheme that: the autoclaved aerated concrete slab prepared from the desert sand comprises a composite material formed by the following components in parts by weight: 55-65 parts of desert sand, 15-30 parts of cement, 4-12 parts of quick lime, 3-10 parts of slaked lime, 3-9 parts of gypsum, 1-5 parts of aluminum powder, 0.5-1 part of foam stabilizer, 0.5-1 part of kaolin and 0.5-1 part of bentonite, wherein the weight ratio of the combined material to water is 1: 0.57 to 0.63.

In the embodiment of the invention, the content of silicon dioxide in the desert sand is not less than 65%, and the content of mud in the desert sand is not more than 2%.

In the embodiment of the invention, the cement is ordinary portland cement, and the strength grade is not lower than 42.5.

In the embodiment of the invention, the foam stabilizer is any one of calcium stearate, gleditsia sinensis lam powder and naphthalene saponin.

In the embodiment of the invention, a reinforcing mesh is further arranged in the concrete slab.

The invention also provides a preparation method of the autoclaved aerated concrete slab, which comprises the following steps:

s1: placing all raw materials at the ambient temperature of 35-45 ℃ for more than 24 h;

s2: weighing the desert sand, the cement, the quicklime, the hydrated lime, the gypsum, the kaolin and the bentonite in parts by weight, adding water and stirring;

s3: adding aluminum powder and a foam stabilizer of corresponding components, and stirring to obtain slurry;

s4: providing a mould for preparing the autoclaved aerated concrete slab, pouring the slurry obtained in the step S3 into the mould, and standing and maintaining for 2-3 hours in an environment at 40-60 ℃ after pouring is finished;

in the embodiment of the invention, in the step S3, the stirring environment temperature is 35-45 ℃, the stirring speed is 150-200 r/min, and the stirring time is 1-3 h.

In the embodiment of the invention, the method also comprises the steps of processing the reinforcing mesh and placing the processed reinforcing mesh in a mould for standby.

In the embodiment of the invention, the method further comprises the following steps: and after standing and curing, removing the die, cutting and milling the groove to obtain a plate blank, and performing autoclaved curing on the plate blank at the curing temperature of 150-200 ℃.

Due to the adoption of the technical scheme, the invention has the following beneficial effects:

(1) according to the invention, the desert sand is used for replacing quartz sand or common natural sand as a siliceous material, and the prepared autoclaved aerated concrete can meet the requirements of building materials, can greatly reduce the construction cost and protect the ecological environment, has more obvious advantages particularly for desertification regions, and has wide market prospects.

(2) The cement is a main source of the strength of the desert sand autoclaved aerated concrete, provides a main calcareous material for the aerated concrete, is suitable for producing cement of the desert sand autoclaved aerated concrete, is mainly selected according to two aspects of the variety and the grade of the cement, and firstly, 42.5-grade ordinary portland cement is selected in production.

(3) Lime is also one of the main raw materials for producing desert sand autoclaved aerated concrete, and the main function of the lime is to provide effective calcium oxide by matching with cement so as to enable the calcium oxide to be matched with SiO in siliceous materials under hydrothermal conditions₂、Al₂O₃Acting to produce calcium silicate hydrate. Therefore, lime is one of the main strength sources of the product. The effective calcium oxide content of lime used for producing aerated concrete should be more than 65%, preferably more than 80%. The (JC/T621-1996) standard should be met.

(4) The gypsum is a regulator in the gas generation process in the desert sand autoclaved aerated concrete, and the regulation effect of the gypsum is mainly embodied in the delaying of slaking quicklime and thickening speed of slurry, and the main effect of the gypsum isThe chemical composition is CaSO₄There are three types of gypsum on the market: the gypsum is low in cost, can replace natural gypsum, and reduces the production cost.

(5) The autoclaved aerated concrete slab can form a light porous structure only by using a gas forming material as a gas forming agent and using aluminum powder to enable concrete to generate pores.

(6) According to the invention, the components except the aluminum powder and the foam stabilizer are firstly and uniformly stirred, then the aluminum powder and the foam stabilizer are added, so that the aluminum powder can be promoted to uniformly generate air holes in the concrete, a light porous structure is formed, the foam stabilizer is added, the long-term foam retention property is prolonged and stabilized, and the durability of the air holes generated in the concrete by the aluminum powder is improved.

(7) According to the invention, the raw materials are placed in the environment at the temperature of 35-45 ℃ for more than 24 hours before the slurry is mixed, so that the same temperature of the raw materials can be ensured, the corresponding reaction of the components in the slurry preparation process is promoted, and the strength and the heat conductivity of the autoclaved aerated concrete slab are improved.

Detailed Description

To facilitate an understanding of the present invention, the following description is given in conjunction with the examples.

The invention provides an autoclaved aerated concrete slab prepared from desert sand, which comprises a composite material formed by the following components in parts by weight: 55-65 parts of desert sand, 15-30 parts of cement, 4-12 parts of quick lime, 3-10 parts of slaked lime, 3-9 parts of gypsum, 1-5 parts of aluminum powder, 0.5-1 part of foam stabilizer, 0.5-1 part of kaolin and 0.5-1 part of bentonite, wherein the weight ratio of the combined material to water is 1: 0.57 to 0.63.

In the embodiment of the invention, the content of silicon dioxide in the desert sand is not less than 65 percent, and the content of mud is not more than 2 percent; the cement is ordinary portland cement, and the strength grade is not lower than 42.5; the foam stabilizer is any one of calcium stearate, gleditsia sinensis lam powder and naphthalene saponin.

In the embodiment of the invention, a reinforcing mesh is further arranged in the concrete slab.

The invention also provides a preparation method of the autoclaved aerated concrete slab, which comprises the following steps:

s1: placing all raw materials at the ambient temperature of 35-45 ℃ for more than 24 h;

s2: processing a reinforcing mesh, and placing the processed reinforcing mesh in a mould for later use; specifically, the steel bars are connected by welding;

s3: weighing desert sand, cement, quicklime, slaked lime, gypsum, kaolin and bentonite according to the weight parts shown in Table 1, adding water, and stirring, wherein the stirring environment temperature is 35-45 ℃, the stirring speed is 150-200 r/min, and the stirring time is 1-3 h;

s4: adding aluminum powder and a foam stabilizer of corresponding components, and stirring to obtain slurry, wherein the stirring environment temperature is 35-45 ℃, the stirring speed is 600-800 r/min, and the stirring time is 1-2 h;

s5: pouring the slurry obtained in the fourth step into the mold in the second step, and standing and maintaining for 2-3 hours in an environment at 40-60 ℃ after pouring is finished;

s6: after standing and maintaining, performing die stripping, cutting and groove milling to obtain a plate blank;

s7: and (3) carrying out autoclaved curing on the plate blank at the curing temperature of 150-200 ℃.

TABLE 1 amounts (parts by weight) of the components of the preparation examples