Dry-mixed mortar composition and adhesive slurry

Abstract

The invention provides a dry-mixed mortar composition which comprises the following components in parts by weight: 350-450 parts of an adhesive; the aggregate is aerated concrete particles or a mixture of the aerated concrete particles and sand, and the aggregate is 400-600 parts; and an additive. The invention further provides adhesive slurry which is formed by mixing the dry-mixed mortar composition and water, and the weight ratio of the dry-mixed mortar composition to the water is 100: (20-45). According to the technical scheme, the aerated concrete particles are used for partially or completely replacing river sand to serve as aggregate of the ceramic tile binder, the performance of the obtained product is equivalent to that of a product completely using the river sand, the use amount of the river sand can be saved, and waste can be recycled.

Description

Technical Field

[0001] The invention relates to building materials, in particular to a dry-mixed mortar composition and a bonding slurry prepared from the dry-mixed mortar composition. Background Art

[0002] Ceramic tile adhesive is a new modern decoration material used to stick ceramic tiles, tiles, floor tiles and other decorative materials. Its main features are high bonding strength, water resistance, freeze-thaw resistance, good aging resistance and convenient construction. It is an ideal bonding material. Considering safety, aesthetics, durability, dosage cost and other aspects, it is an important research direction to require ceramic tile adhesive to maintain excellent bonding strength at a lower construction thickness.

[0003] Usually, the aggregate used in tile adhesives is quartz sand, which is mainly sourced from collected river sand. Collecting river sand has a certain degree of damage to the natural environment, so in recent years, relevant policies have reduced or banned the collection of river sand in some areas. Therefore, the industry has also explored the use of construction waste and other waste materials as aggregates to replace river sand or quartz sand.

[0004] Aerated concrete (AAC) is a lightweight and porous building material, mainly made of siliceous materials (such as sand, fly ash) and calcium materials (such as lime, cement), and mixed with gas-generating agents (such as aluminum powder). It is made through batching, mixing, pouring, pre-curing, cutting, autoclaving and other processes.

[0005] Waste is generated during the production and use of aerated concrete. The treatment of these wastes usually includes the manufacture of recycled aggregates, the production of wall bricks, foundation and road pads, and carbonization curing. Summary of the invention

[0006] The purpose of the present invention is to use aerated concrete particles as aggregate in tile adhesive to reduce the amount of river sand used.

[0007] To this end, according to one aspect of the present invention, a dry-mixed mortar composition comprises the following components in parts by weight: a binder, 350-450 parts; an aggregate, which is aerated concrete particles or a mixture of aerated concrete particles and sand, 400-600 parts; and an additive.

[0008] Wherein, the aggregate includes coarse aggregate, wherein the coarse aggregate is coarse particles of aerated concrete or a mixture of coarse particles of aerated concrete and coarse sand.

[0009] Wherein, in the mixture of the aerated concrete coarse particles and the coarse sand particles, the volume of the aerated concrete coarse particles is at least 25%, or at least 50%, of the total volume of the coarse aggregate. Alternatively, in the mixture of the aerated concrete coarse particles and the coarse sand particles, the weight of the aerated concrete coarse particles is at least 20%, or at least 50%, or at least 75% of the total weight of the coarse aggregate.

[0010] Wherein, the aggregate includes fine aggregate, and the fine aggregate is aerated concrete fine particles or a mixture of aerated concrete fine particles and fine sand.

[0011] Wherein, in the mixture of the aerated concrete fine particles and the fine sand, the volume of the aerated concrete fine particles is at least 25%, or at least 50%, of the total volume of the fine aggregate. Alternatively, in the mixture of the aerated concrete fine particles and the fine sand, the weight of the aerated concrete fine particles is at most 50% of the weight of the fine aggregate.

[0012] The additive includes cellulose ether in an amount of 1-5 parts by weight. The additive may also include redispersible latex powder in an amount of up to 40 parts by weight. Further, the additive may also include calcium formate in an amount of up to 10 parts by weight.

[0013] Wherein, in the mixture of aerated concrete particles and sand, the volume of the aerated concrete particles is at least 10%, or 25%, or at least 50% of the total volume of the aggregate.

[0014] Wherein, the weight of the aerated concrete particles is 4%-55% of the total weight of the aggregate.

[0015] According to another aspect of the present invention, a bonding slurry is formed by mixing the aforementioned dry-mixed mortar composition and water, wherein the weight ratio of the dry-mixed mortar composition to water is 100:20-45.

[0016] In the technical solution of the present invention, aerated concrete particles are used to partially or completely replace river sand as aggregate of tile adhesive. The performance of the obtained product is equivalent to that of the product using river sand completely, the amount of river sand can be saved, and waste materials can be recycled. DETAILED DESCRIPTION

[0017] The specific embodiments of the present invention are described below in conjunction with examples. In the context of this application, the contents of each component listed are parts by weight.

[0018] According to the present invention, a dry-mixed mortar composition can be used as a tile adhesive, which includes a binder, an aggregate and an additive. Among them, a hydraulic cementitious material is used as a binder, a mixture of sand or aerated concrete particles is used as an aggregate, and the additive can be selected from any one or any combination of redispersible latex powder, a coagulant, a water retaining agent, a water reducing agent, a rheological agent and an early strength agent.

[0019] The hydraulic cementitious material may be silicate cement, which is a commercially available product, such as a product that complies with the national standard GB175-2023 "General silicate cement". In the following example, silicate cement with a P·I of 42.5 is used. The hydraulic cementitious material may also be a mixture of silicate cement and fly ash. Fly ash may also be commercially available, such as a product that complies with the national standard GB / T 1596. The total content of the binder is 350-450 parts.

[0020] Aggregates may include fine aggregates and coarse aggregates. The fine aggregates are particles with a particle size of less than 0.3 mm, and the coarse aggregates are particles with a particle size between 0.3 mm and 0.6 mm. The particle size is a parameter describing the particle size obtained by sieve analysis based on the national standard GBT17431.2-2010 or ASTM C136. The total content of aggregates is 400-600 parts.

[0021] The sand used as aggregate can be standard sand, such as ISO standard sand. According to the particle size, it can be divided into fine sand and coarse sand, which are used as coarse aggregate and fine aggregate respectively. Similarly, aerated concrete particles can also be divided into aerated concrete fine particles and coarse particles according to the particle size, which are used as coarse aggregate and fine aggregate respectively.

[0022] The additives may be formulations commonly used in mortar products and may be obtained through commercial channels. In the present application, when the content is not specified, the amount of the additives may refer to the usual amount in the art. Typically, the content of cellulose ether is 1-5 parts, the content of redispersible latex powder is up to 40 parts or up to 10 parts, and the content of calcium formate is up to 10 parts.

[0023] The dry-mixed mortar composition is mixed with water to obtain an adhesive slurry for bonding tiles, wherein the weight ratio of the dry-mixed mortar composition to water is 100:20-45.

[0024] The first set of embodiments

[0025] As shown in Table 1, Examples 1-6 are the first group of examples. In this group of examples, compared with Control Example 1, sand is replaced by aerated concrete particles in an equal volume replacement manner.

[0026] In Examples 1-3, fine aerated concrete particles were used to replace 25%, 50% and 100% of the volume of fine sand, respectively. In Examples 4-6, coarse aerated concrete particles were used to replace 25%, 50% and 100% of the volume of coarse sand, respectively. Since the bulk density of aerated concrete particles is less than that of sand, the total weight of the aggregate is reduced.

[0027] Table 1

[0028] Comparative Example 1 Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Portland cement 280 280 280 280 280 280 280 Fly ash 100 100 100 100 100 100 100 Fine sand 310 232.5 155 0 310 310 310 Aerated concrete fine particles 0 33.5 67 134 0 0 0 coarse sand 310 310 310 310 232.5 155 0 Aerated concrete coarse particles 0 0 0 0 28.1 56.2 112.4 Cellulose ether 3 3 3 3 3 3 3 water 220 230 240 260 230 240 260

[0029] According to the components and contents in Table 1, a bonding slurry is prepared. The bonding slurry is prepared by: preparing the components according to the contents in Table 1; mixing the components uniformly; adding water in the content shown in Table 1, and further stirring to obtain a slurry.

[0030] The bonding strength was tested according to the method in the standard “JCT 547-2017 Ceramic Tile Adhesive”. The results are shown in Table 2, and the unit is megapascal (MPa).

[0031] Table 2

[0032]

[0033]

[0034] It can be seen from Table 4 that the bonding strength of Examples 1-6 is greater than 0.5 MPa, or is approximately 0.5 MPa. Therefore, aerated concrete particles can be used to replace sand as aggregate by an equal volume replacement method.

[0035] Second set of embodiments

[0036] As shown in Table 3, Examples 7-18 are the second group of examples. In this group of examples, compared with Control Example 2, aerated concrete particles are used to replace sand in an equal weight replacement manner. In Examples 7-10, aerated concrete coarse particles are used to replace 25%, 50%, 75% and 100% of the weight of coarse sand, respectively. In Example 11, aerated concrete coarse particles are used to replace 50% of the weight of coarse sand, and aerated concrete fine particles are used to replace 25% of the weight of fine sand. In Examples 12-18, aerated concrete fine particles are used to replace 50% of the weight of fine sand.

[0037] Due to the different bulk densities, the volume of aerated concrete particles of the same weight is larger than that of sand, thereby increasing the volume of the dry-mixed mortar composition. In order to maintain strength, the amount of binder can be increased. Alternatively, redispersible latex powder can be used to increase strength. In the second group of embodiments, calcium formate is used as an early strength agent. The filler is limestone powder.

[0038] Table 3

[0039]

[0040] Similarly, an adhesive slurry was prepared according to the components and proportions in Table 3. The bonding strength was tested according to the method in the standard "JCT 547-2017 Ceramic Tile Adhesive", and the results are shown in Table 4, in megapascals (MPa).

[0041] Table 4

[0042] 7 days bond strength 28 days bond strength Comparative Example 2 2.14 2.28 Example 7 1.96 2.52 Example 8 1.00 1.46 Example 9 0.83 0.70 Example 10 0.70 0.60 Embodiment 11 0.90 0.71 Example 12 0.71 0.54 Embodiment 13 0.72 0.55 Embodiment 14 0.85 0.73 Embodiment 15 0.78 0.58 Example 16 0.97 0.80 Embodiment 17 1.03 0.88 Embodiment 18 0.77 1.07 Embodiment 19 0.98 1.28 Embodiment 20 0.80 0.98

[0043] As shown in Table 4, the bond strengths of Examples 7-18 are all greater than 0.5 MPa, so aerated concrete particles can be used as aggregate instead of sand by equal weight substitution.

[0044] In the above description, the details of the technical solution of the present invention are explained. However, those skilled in the art can understand that the present invention is not limited to the specific details listed in the above embodiments, but can be changed within the scope defined by the claims.

Claims

1. A dry-mixed mortar composition comprising the following components in parts by weight: 350-450 parts of a binder; 400-600 parts of an aggregate, which is aerated concrete particles or a mixture of aerated concrete particles and sand; and an additive.

2. The dry-mix mortar composition according to claim 1, wherein: The aggregate comprises coarse aggregate, wherein the coarse aggregate is coarse particles of aerated concrete or a mixture of coarse particles of aerated concrete and coarse sand.

3. The dry-mix mortar composition according to claim 2, wherein: In the mixture of the aerated concrete coarse particles and the coarse sand particles, the volume of the aerated concrete coarse particles is at least 25%, or at least 50% of the total volume of the coarse aggregate.

4. The dry-mix mortar composition according to claim 2, wherein: In the mixture of the aerated concrete coarse particles and the coarse sand particles, the weight of the aerated concrete coarse particles is at least 20%, or at least 50%, or at least 75% of the total weight of the coarse aggregate.

5. The dry-mix mortar composition according to claim 1, wherein: The aggregate includes fine aggregate, and the fine aggregate is aerated concrete fine particles or a mixture of aerated concrete fine particles and fine sand.

6. The dry-mix mortar composition according to claim 5, wherein: In the mixture of the aerated concrete fine particles and fine sand, the volume of the aerated concrete fine particles is at least 25%, or at least 50% of the total volume of the fine aggregate.

7. The dry-mix mortar composition according to claim 5, wherein: In the mixture of the aerated concrete fine particles and fine sand, the weight of the aerated concrete fine particles is at most 50% of the weight of the fine aggregate.

8. The dry-mix mortar composition according to claim 1, wherein: The additive includes cellulose ether, and its weight portion is 1-5 parts.

9. The dry-mix mortar composition according to claim 1, wherein: The additives include redispersible latex powder, and its weight parts are at most 40 parts.

10. The dry-mix mortar composition according to claim 1, wherein: The additive includes calcium formate in an amount of up to 10 parts by weight.

11. The dry-mix mortar composition according to claim 1, wherein: In the mixture of aerated concrete particles and sand, the volume of the aerated concrete particles is at least 10%, or 25%, or at least 50% of the total volume of the aggregate.

12. The dry-mix mortar composition according to claim 1, wherein: The weight of the aerated concrete particles is 4%-55% of the total weight of the aggregate.

13. A bonding slurry, which is formed by mixing the dry-mixed mortar composition according to any one of claims 1 to 12 and water, wherein: The weight ratio of the dry-mixed mortar composition to water is 100:20-45.

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