A high-toughness concrete decorative brick, its preparation method and application

Abstract

The present invention relates to the technical field of concrete, and specifically discloses a high-toughness concrete decorative brick, its preparation method and application, which include the following components in parts by weight: 500-600 parts of cement, 120-150 parts of nano-clay, 80-100 parts of modified fiber-reinforced polypropylene, 1000-1200 parts of aggregate, 3-5 parts of water reducer, and 100-200 parts of water; wherein, the fibers used in the modified fiber-reinforced polypropylene are glass fiber and carbon fiber; the polypropylene used in the modified fiber-reinforced polypropylene is maleic anhydride grafted polypropylene, and potassium feldspar powder is added to the maleic anhydride grafted polypropylene. Among them, the nano-clay is a mixture of bentonite powder and potassium feldspar powder. The high-toughness concrete decorative brick of the present invention has both high tensile strength and fracture toughness, and is particularly suitable for preparing decorative walls and floors.

Description

Technical Field

[0001] The present invention relates to the technical field of concrete, and particularly relates to a high-toughness concrete decorative brick, a preparation method thereof, and an application thereof. Background Art

[0002] Concrete is a common building material. According to the usage requirements of application scenarios, corresponding functional requirements can be achieved through concrete formulation design.

[0003] For common decorative walls and floors, it is necessary to prepare concrete into decorative bricks. The decorative bricks need to form ornamental colors, textures, and patterns on their surfaces, and are required to have high tensile strength, fracture toughness, impermeability, etc. For decorative bricks used for exterior wall decoration, they are also required to have good crack resistance to expansion, etc. For other decorative bricks such as floors that need to be frequently cleaned, they are also required to have good chemical corrosion resistance.

[0004] In the prior art, modification is mainly carried out by introducing high-performance fibers (such as steel fibers, etc.) into concrete to improve the tensile strength and crack resistance of concrete, and it has good adaptability in scenarios that need to bear large loads and impacts. However, for the concrete used in decorative bricks, not only is it required that the concrete has high tensile strength, but also high fracture toughness; and, some decorative walls and floors are used in humid environments, and fibers such as steel fibers are easily corroded, especially in humid or chloride ion environments. Summary of the Invention

[0005] The purpose of the present invention is to provide a high-toughness concrete decorative brick with both high tensile strength and fracture toughness.

[0006] In addition, the present invention also provides a preparation method and an application of the above-mentioned high-toughness concrete decorative brick.

[0007] The present invention is achieved through the following technical solutions:

[0008] A high-toughness concrete decorative brick, comprising the following components in parts by weight:

[0009] 500 - 600 parts of cement, 120 - 150 parts of nano-clay, 80 - 100 parts of modified fiber-reinforced polypropylene, 1000 - 1200 parts of aggregate, 3 - 5 parts of water-reducing agent, 100 - 200 parts of water;

[0010] Among them, the fibers used in the modified fiber-reinforced polypropylene are glass fibers and carbon fibers; the polypropylene used in the modified fiber-reinforced polypropylene is maleic anhydride grafted polypropylene, and potassium feldspar powder is added to the maleic anhydride grafted polypropylene;

[0011] Among them, the nano-clay is a mixture of bentonite powder and potassium feldspar powder;

[0012] Among them, the potassium feldspar powder is modified potassium feldspar powder; the preparation process of the modified potassium feldspar powder is as follows:

[0013] Mix the potassium feldspar powder with activated carbon powder for 30 - 60 minutes. Among them, the particle size of the activated carbon powder is smaller than that of the potassium feldspar powder. Then, remove the activated carbon powder by sieving method. Then, mix the potassium feldspar powder with zinc spar powder and calcium carbonate powder and ball mill for 30 minutes. Among them, based on the weight of the potassium feldspar powder, the dosage of the zinc spar powder is 10%, the dosage of the activated carbon powder is 5%, and the dosage of the calcium carbonate powder is 8%.

[0014] The present invention introduces nano - clay and modified fiber - reinforced polypropylene on the basis of existing concrete to prepare high - toughness concrete decorative bricks; among them, the nano - clay is a nano - scale filler, which can improve the mechanical properties of concrete. Moreover, the nano - clay is evenly dispersed in the concrete, which can effectively prevent crack propagation, thereby improving the toughness of the concrete. Among them, the modified fiber - reinforced polypropylene can improve the toughness and tensile strength of the concrete, and can effectively disperse external stress, reduce the stress concentration inside the concrete, and then prevent crack propagation. It can also improve the density of the concrete and effectively reduce the penetration of moisture and chemical substances. The fiber used in the modified fiber - reinforced polypropylene of the present invention is a composite fiber (mixed fiber) of glass fiber and carbon fiber. Compared with using glass fiber alone, it can improve the toughness and tensile strength of the concrete; using maleic anhydride - grafted polypropylene as the resin can improve the toughness of the concrete compared with directly using polypropylene. And by introducing potassium feldspar powder into maleic anhydride - grafted polypropylene, since the potassium feldspar powder contains potassium and has a certain interlayer stability and is not easy to expand, it can improve the mechanical properties of maleic anhydride - grafted polypropylene and can improve the tensile strength and toughness of the modified fiber - reinforced polypropylene.

[0015] Among them, the bentonite powder is a substance that can absorb water and become a gel - like substance. When the gel - like substance formed by the bentonite powder is dispersed in the concrete, it can improve the toughness and density of the concrete; among them, the potassium feldspar powder contains potassium and has a certain interlayer stability and is not easy to expand. Mixing the bentonite powder and the potassium feldspar powder can further improve the toughness and density of the concrete.

[0016] Among them, when the potassium feldspar powder is modified with activated carbon powder, smithsonite powder and calcium carbonate powder, the tensile strength and toughness of the concrete can be further improved. Among them, activated carbon has a very high specific surface area and strong adsorption capacity, which can effectively adsorb harmful impurities and pollutants existing in the potassium feldspar powder, thereby improving the purity and quality of the potassium feldspar powder, and further enhancing the activity of the potassium feldspar powder. Smithsonite powder and calcium carbonate powder, as additives, can further improve the activity of the potassium feldspar powder. Ball milling the potassium feldspar powder together with the smithsonite powder and calcium carbonate powder can, on the one hand, improve the surface activity of the potassium feldspar powder, smithsonite powder and calcium carbonate powder, which is conducive to the modification of the high-potassium feldspar powder by the smithsonite powder and calcium carbonate powder as additives. On the other hand, it can improve the uniformity of the mixture of the potassium feldspar powder, smithsonite powder and calcium carbonate powder.

[0017] In summary, by introducing nano-clay and modified fiber-reinforced polypropylene into the concrete, the prepared high-toughness concrete decorative brick has both high tensile strength and fracture toughness.

[0018] In a preferred embodiment, the weight ratio of bentonite powder to potassium feldspar powder is (3 - 4):1.

[0019] In a preferred embodiment, the preparation process of the modified fiber-reinforced polypropylene is as follows:

[0020] First, the glass fiber and carbon fiber are respectively surface-treated with nano-silica, then the surface-treated glass fiber and carbon fiber are mixed, and then the mixed fibers are mixed with maleic anhydride grafted polypropylene, and then the modified fiber-reinforced polypropylene is obtained by an extrusion process.

[0021] In a preferred embodiment, based on the weight of maleic anhydride grafted polypropylene, the addition amount of potassium feldspar powder in maleic anhydride grafted polypropylene is 12 - 15%.

[0022] Although adding a certain amount of potassium feldspar powder to maleic anhydride grafted polypropylene can improve the tensile strength and fracture toughness of the concrete, when the addition amount of potassium feldspar powder is too much, the opposite effect will occur.

[0023] In a preferred embodiment, the aggregate includes coarse aggregate and fine aggregate; the particle size of the coarse aggregate is (2.5 - 2.0) mm, and the particle size of the fine aggregate is (0.5 - 0.8) mm; the weight ratio of the coarse aggregate to the fine aggregate is 1:(0.5 - 0.6).

[0024] The bulk density of the aggregate has an impact on the strength and density of the concrete. By reasonably setting the particle size and weight ratio of the coarse aggregate and fine aggregate, the strength and density of the concrete can be improved, and further the impermeability of the concrete is enhanced.

[0025] In a preferred embodiment, the high-toughness concrete decorative brick further comprises 30-50 parts of mineral admixture; the mineral admixture is a mixture of fly ash and slag powder, and the weight ratio of fly ash to slag powder is (2-3):1.

[0026] By adding fly ash and slag powder to the high-toughness concrete decorative brick simultaneously, the present invention can improve the chemical erosion resistance of the high-toughness concrete decorative brick.

[0027] In a preferred embodiment, the water-binder ratio of the high-toughness concrete decorative brick is (0.20-0.25).

[0028] The water-binder ratio of concrete affects the compactness of concrete. When the water-binder ratio of concrete is too large, it will lead to a lower compactness of concrete and reduce its impermeability.

[0029] A preparation method of a high-toughness concrete decorative brick comprises the following steps:

[0030] S1. Prepare modified fiber-reinforced polypropylene:

[0031] S11. First, surface-treat glass fiber and carbon fiber with nano-silica respectively;

[0032] S12. Mix the glass fiber and the carbon fiber treated in step S11 in a weight ratio of 3:1. The lengths of both the glass fiber and the carbon fiber are 15-20 mm;

[0033] S13. Disperse the potassium feldspar powder in the maleic anhydride grafted polypropylene, then mix the mixed fiber with the maleic anhydride grafted polypropylene evenly, put them into an extruder for extrusion molding, cooling and pelletizing to obtain the modified fiber-reinforced polypropylene;

[0034] S2. Add cement, nano-clay, aggregate and water reducer into a forced mixer according to a proportion, dry-mix the mixture at a speed of 35-45 r / min for 3-4 min, add water for fluidized stirring for 3-4 min, then add the modified fiber-reinforced polypropylene, and continue stirring for 4-5 min to obtain concrete. Pour the concrete into a mold and cure it to obtain the high-toughness concrete decorative brick.

[0035] In a preferred embodiment, the weight ratio of the composite long glass fiber to the maleic anhydride grafted polypropylene in the modified fiber-reinforced polypropylene is (2-3):(3-5); based on the weight of the maleic anhydride grafted polypropylene, the addition amount of the potassium feldspar powder in the maleic anhydride grafted polypropylene is 12-15%.

[0036] By pretreating glass fibers and carbon fibers with nano-silica, the present invention can increase the surface roughness and hydrophobicity of glass fibers and carbon fibers, so that the bonding force between glass fibers and carbon fibers and other components in concrete is greater, ensuring the reinforcement effect of fibers on maleic anhydride grafted polypropylene.

[0037] The application of a high-toughness concrete decorative brick is used for preparing products including decorative walls or floors.

[0038] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0039] The present invention introduces nano-clay and modified fiber-reinforced polypropylene on the basis of existing concrete to prepare a high-toughness concrete decorative brick; among them, the nano-clay is a nano-level filler that can improve the mechanical properties of concrete and effectively prevent crack propagation; the modified fiber-reinforced polypropylene can improve the toughness and tensile strength of concrete, making the prepared high-toughness concrete decorative brick have both high tensile strength and fracture toughness, and is particularly suitable for the preparation of decorative walls or floors. Detailed implementation manners

[0040] To make the purpose, technical solutions and advantages of the present invention clearer and more understandable, the present invention will be further described in detail below with reference to the embodiments. The illustrative embodiments and descriptions of the present invention are only used to explain the present invention and are not intended to limit the present invention. The following described embodiments are part of the embodiments of the present invention, not all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts fall within the scope of protection of the present invention.

[0041] In the following description, a large number of specific details are set forth in order to provide a thorough understanding of the present invention. However, it is obvious to those of ordinary skill in the art that: it is not necessary to adopt these specific details to implement the present invention. In other embodiments, well-known structures, materials or methods are not specifically described in order to avoid obscuring the present invention. The materials, instruments and reagents used in the following embodiments, unless otherwise specified, can be obtained from commercial sources. The technical means used in the embodiments, unless otherwise specified, are conventional means well-known to those skilled in the art.

[0042] In order to improve the tensile strength and fracture toughness of concrete, this embodiment provides a high-toughness concrete decorative brick, which includes the following components in parts by weight:

[0043] 500 - 600 parts of cement, 120 - 150 parts of nano-clay, 80 - 100 parts of modified fiber-reinforced polypropylene, 1000 - 1200 parts of aggregate, 3 - 5 parts of water reducing agent, 100 - 200 parts of water;

[0044] Among them, the fibers used in the modified fiber-reinforced polypropylene are glass fibers and carbon fibers; the polypropylene used in the modified fiber-reinforced polypropylene is maleic anhydride-grafted polypropylene, and potassium feldspar powder is added to the maleic anhydride-grafted polypropylene; based on the weight of the maleic anhydride-grafted polypropylene, the addition amount of potassium feldspar powder in the maleic anhydride-grafted polypropylene is 12-15%. Among them, the maleic anhydride-grafted polypropylene is a prior art, and preferably a purchased product with a grafting rate of 1.1% and a melt index of 180 g / 10 min is used; among them, the melt index is the flow rate measured under the conditions of 230 °C and a load of 2.16 kg. The preparation process of the modified fiber-reinforced polypropylene is as follows:

[0045] First, the glass fibers and carbon fibers are respectively surface-treated with nano-silica, then the surface-treated glass fibers and carbon fibers are mixed in proportion, and then the mixed fibers are mixed with maleic anhydride-grafted polypropylene, and then the modified fiber-reinforced polypropylene is obtained by an extrusion process.

[0046] Among them, the water-reducing agent is preferably a polycarboxylate water-reducing agent or a naphthalene-based water-reducing agent. The polycarboxylate water-reducing agent and the naphthalene-based water-reducing agent can significantly reduce the water-binder ratio of the concrete while maintaining the basic unchanged slump of the concrete, thereby improving the strength and durability of the concrete. Both the polycarboxylate water-reducing agent and the naphthalene-based water-reducing agent are obtained by purchase.

[0047] Among them, the cement is ordinary Portland cement.

[0048] Among them, the nano-clay is nano-particles of layered mineral silicate; such as montmorillonite, bentonite, halloysite nano-clay, etc.; in a preferred case, the nano-clay is a mixture of bentonite powder and potassium feldspar powder, and among them, the weight ratio of bentonite powder to potassium feldspar powder is (3-4):1.

[0049] In a preferred case, the aggregate includes coarse aggregate and fine aggregate; the particle size of the coarse aggregate is (2.5-2.0) mm, and the particle size of the fine aggregate is (0.5-0.8) mm; the weight ratio of the coarse aggregate to the fine aggregate is 1:(0.5-0.6); to improve the compactness of the concrete, the aggregate can specifically be river sand, machine-made sand, etc.

[0050] In a preferred case, the water-binder ratio of the high-toughness concrete decorative brick is (0.20-0.25). The lower water-binder ratio can improve the compactness of the concrete, thereby improving its impermeability. Among them, the water-binder ratio is the ratio of water to the gel material (the total weight of cement and nano-clay) in the high-toughness concrete decorative brick.

[0051] In a preferred case, the high-toughness concrete decorative brick further comprises 30-50 parts of mineral admixture; the mineral admixture is a mixture of fly ash and slag powder, and the mass ratio of fly ash to slag powder is (2-3):1. The combination of fly ash and slag can significantly improve the weakness of poor chemical erosion resistance of slag concrete. Among them, fly ash is the substance discharged from the flue after the pulverized coal ash in the coal-fired power plant burns in the boiler and collected by the dust collector, and its main components are SiO 2 、Al 2 O 3 and Fe 2 O 3 ‌; slag powder is an industrial by-product generated during the iron-making process, and its main components are CaO, SiO 2 and Al 2 O 3 ‌.

[0052] In a preferred case, the potassium feldspar powder is modified potassium feldspar powder; the preparation process of the modified potassium feldspar powder is as follows:

[0053] Mix the potassium feldspar powder and the activated carbon powder for 30-60 min. Among them, the particle size of the activated carbon powder is smaller than that of the potassium feldspar powder. The activated carbon powder has a smaller particle size and a larger specific surface area, and can better adsorb impurities. Then, remove the activated carbon powder by sieving method, and then mix the potassium feldspar powder with zinc spar powder and calcium carbonate powder and ball mill for 30 min. Among them, based on the weight of the potassium feldspar powder, the dosage of zinc spar powder is 10%, the dosage of activated carbon powder is 5%, and the dosage of calcium carbonate powder is 8%. By modifying the potassium feldspar powder, the tensile strength and fracture toughness of the concrete can be further improved.

[0054] The preparation method of the above-mentioned high-toughness concrete decorative brick comprises the following steps:

[0055] S1. Prepare modified fiber-reinforced polypropylene:

[0056] S11. First, surface-treat the glass fiber and carbon fiber with nano-silica respectively. The single filament diameters of the glass fiber and carbon fiber are both 15-20 μm; the specific process is as follows: prepare an aqueous solution containing nano-silica by ultrasonic dispersion, and then immerse the glass fiber and carbon fiber in the aqueous solution containing nano-silica respectively. Specifically, mix the nano-silica powder and water according to the weight ratio of 1:4, perform ultrasonic treatment for 45 min, and use the surface tension of the fiber to make the nano-silica particles adhere to the surfaces of the glass fiber and carbon fiber, which can enhance the surface roughness and affinity of the glass fiber and carbon fiber.

[0057] S12. Mix the glass fiber and carbon fiber treated in step S11 according to the weight ratio of 3:1. The lengths of the glass fiber and carbon fiber are both 15-20 mm.

[0058] S13. Disperse potassium feldspar powder in maleic anhydride grafted polypropylene, and then mix the mixed fibers evenly with maleic anhydride grafted polypropylene; based on the weight of maleic anhydride grafted polypropylene, the addition amount of potassium feldspar powder in maleic anhydride grafted polypropylene is 12 - 15%; in the modified fiber reinforced polypropylene, the mass ratio of the mixed fibers to maleic anhydride grafted polypropylene is 3:5. Put them into an extruder for extrusion molding, cooling, and pelletizing to obtain modified fiber reinforced polypropylene.

[0059] S2. Add cement, nano - clay, aggregate, and water - reducing agent in proportion to a forced mixer and dry - mix the mixture at a speed of 35 r / min for 4 min. After adding water for fluidized stirring for 4 min; add the modified fiber reinforced polypropylene and continue stirring for 5 min to obtain concrete. Pour the concrete into a mold and cure it conventionally for 28 days to obtain high - toughness concrete decorative bricks.

[0060] The high - toughness concrete decorative bricks prepared in this example have both high tensile strength and fracture toughness, and are particularly suitable for the preparation of decorative walls or floors.

[0061] To better illustrate the effects of this example, the following specific cases are used for illustration.

[0062] Example 1:

[0063] A kind of high - toughness concrete decorative brick is composed of the following components in parts by weight:

[0064] 600 parts of ordinary portland cement, 150 parts of nano - clay, 100 parts of modified fiber reinforced polypropylene, 1200 parts of aggregate, 5 parts of polycarboxylate water - reducing agent, and 180 parts of water.

[0065] In this example, the water - binder ratio of the high - toughness concrete decorative brick is 0.24.

[0066] Among them, the nano - clay is obtained by mixing bentonite powder and potassium feldspar powder in a weight ratio of 4:1;

[0067] Among them, the aggregate is manufactured sand, and the aggregate includes coarse aggregate and fine aggregate; the particle size of the coarse aggregate is (2.5 - 2.0) mm, and the particle size of the fine aggregate is (0.5 - 0.8) mm; the weight ratio of the coarse aggregate to the fine aggregate is 1:0.6;

[0068] Among them, in the process of preparing the modified fiber reinforced polypropylene, based on the weight of maleic anhydride grafted polypropylene, the addition amount of potassium feldspar powder in maleic anhydride grafted polypropylene is 12%.

[0069] Example 2:

[0070] This example is based on Example 1. The difference from Example 1 is that the dosages of the components in the formula are different, specifically as follows:

[0071] A high-toughness concrete decorative brick is composed of the following components in parts by weight:

[0072] 500 parts of ordinary Portland cement, 120 parts of nano-clay, 80 parts of modified fiber-reinforced polypropylene, 1000 parts of aggregate, 3 parts of polycarboxylate water reducer, and 150 parts of water.

[0073] In this example, the water-binder ratio of the high-toughness concrete decorative brick is 0.24.

[0074] Example 3:

[0075] This example is based on Example 1. The difference from Example 1 is that the addition amount of potassium feldspar powder in the modified fiber-reinforced polypropylene is different. Specifically:

[0076] In the process of preparing the modified fiber-reinforced polypropylene, based on the weight of maleic anhydride-grafted polypropylene, the addition amount of potassium feldspar powder in the maleic anhydride-grafted polypropylene is 15%.

[0077] Example 4:

[0078] This example is based on Example 1. The difference from Example 1 is that 50 parts of mineral admixture are also added to the formula, specifically as follows:

[0079] A high-toughness concrete decorative brick is composed of the following components in parts by weight:

[0080] 600 parts of ordinary Portland cement, 150 parts of nano-clay, 100 parts of modified fiber-reinforced polypropylene, 1200 parts of aggregate, 5 parts of polycarboxylate water reducer, 50 parts of mineral admixture, and 180 parts of water.

[0081] The mineral admixture is a mixture of fly ash and slag powder, and the mass ratio of fly ash to slag powder is 3:1.

[0082] Example 5:

[0083] This example is based on Example 1. The difference from Example 1 is that 30 parts of mineral admixture are also added to the formula, specifically as follows:

[0084] A high-toughness concrete decorative brick is composed of the following components in parts by weight:

[0085] 600 parts of ordinary Portland cement, 150 parts of nano-clay, 100 parts of modified fiber-reinforced polypropylene, 1200 parts of aggregate, 5 parts of polycarboxylate water reducer, 30 parts of mineral admixture, and 180 parts of water.

[0086] Example 6:

[0087] This example is based on Example 1, and the difference from Example 1 is that: in this example, potassium feldspar powder is replaced by modified potassium feldspar powder, and the specific preparation process of the modified potassium feldspar powder is as follows:

[0088] Mix potassium feldspar powder with activated carbon powder for 60 minutes. Based on the weight of potassium feldspar powder, the dosage of activated carbon powder is 5%; among them, the particle size of activated carbon powder is smaller than that of potassium feldspar powder. Then, remove the activated carbon powder by screening method. Next, mix the potassium feldspar powder with smithsonite powder and calcium carbonate powder and then ball-mill for 30 minutes. Based on the weight of potassium feldspar powder, the dosage of smithsonite powder is 10%, and the dosage of calcium carbonate powder is 8%.

[0089] Example 7:

[0090] This example is based on Example 5, and the difference from Example 5 is that: in this example, potassium feldspar powder is replaced by modified potassium feldspar powder, and the specific preparation process of the modified potassium feldspar powder is as follows:

[0091] Mix potassium feldspar powder with activated carbon powder for 60 minutes. Based on the weight of potassium feldspar powder, the dosage of activated carbon powder is 5%; among them, the particle size of activated carbon powder is smaller than that of potassium feldspar powder. Then, remove the activated carbon powder by screening method. Next, mix the potassium feldspar powder with smithsonite powder and calcium carbonate powder and then ball-mill for 30 minutes. Based on the weight of potassium feldspar powder, the dosage of smithsonite powder is 10%, and the dosage of calcium carbonate powder is 8%.

[0092] Comparative Example 1:

[0093] This comparative example is based on Example 1, and the difference from Example 1 is that: the formula does not contain nano-clay and modified fiber-reinforced polypropylene. Specifically:

[0094] A high-toughness concrete decorative brick is composed of the following components in parts by weight:

[0095] 600 parts of ordinary Portland cement, 1200 parts of aggregate, 5 parts of polycarboxylate water reducer, and 180 parts of water.

[0096] The water-binder ratio in this comparative example is.

[0097] Comparative Example 2:

[0098] This comparative example is based on Example 1, and the difference from Example 1 is that: the formula does not contain nano-clay. Specifically:

[0099] A high-toughness concrete decorative brick is composed of the following components in parts by weight:

[0100] 600 parts of ordinary Portland cement, 100 parts of modified fiber-reinforced polypropylene, 1200 parts of aggregate, 5 parts of polycarboxylate water reducer, 180 parts of water.

[0101] In this comparative example, the water-binder ratio is.

[0102] Comparative Example 3:

[0103] This comparative example is based on Example 1, and the difference from Example 1 is that: the modified fiber-reinforced polypropylene is not included in the formula. Specifically:

[0104] A high-toughness concrete decorative brick is composed of the following components in parts by weight:

[0105] 600 parts of ordinary Portland cement, 150 parts of nano-clay, 1200 parts of aggregate, 5 parts of polycarboxylate water reducer, 180 parts of water.

[0106] In this comparative example, the water-binder ratio is.

[0107] Comparative Example 4:

[0108] This comparative example is based on Example 1, and the difference from Example 1 is that: steel fiber is used to replace the modified fiber-reinforced polypropylene. Specifically:

[0109] A high-toughness concrete decorative brick is composed of the following components in parts by weight:

[0110] 600 parts of ordinary Portland cement, 150 parts of nano-clay, 100 parts of steel fiber, 1200 parts of aggregate, 5 parts of polycarboxylate water reducer, 180 parts of water.

[0111] Comparative Example 5:

[0112] This comparative example is based on Example 1, and the difference from Example 1 is that: bentonite is used to replace nano-clay.

[0113] A high-toughness concrete decorative brick is composed of the following components in parts by weight:

[0114] 600 parts of ordinary Portland cement, 150 parts of bentonite, 100 parts of steel fiber, 1200 parts of aggregate, 5 parts of polycarboxylate water reducer, 180 parts of water.

[0115] Comparative Example 6:

[0116] This comparative example is based on Example 1, and the difference from Example 1 is that:

[0117] During the preparation of the modified fiber-reinforced polypropylene, potassium feldspar powder is not added.

[0118] Comparative Example 7:

[0119] This comparative example is based on Example 1, and the difference from Example 1 is that: during the preparation of modified fiber-reinforced polypropylene, the addition amount of potassium feldspar powder is different. Specifically:

[0120] During the preparation of modified fiber-reinforced polypropylene, based on the weight of maleic anhydride-grafted polypropylene, the addition amount of potassium feldspar powder in maleic anhydride-grafted polypropylene is 10%.

[0121] Comparative Example 8:

[0122] This comparative example is based on Example 1, and the difference from Example 1 is that: during the preparation of modified fiber-reinforced polypropylene, the addition amount of potassium feldspar powder is different. Specifically:

[0123] During the preparation of modified fiber-reinforced polypropylene, based on the weight of maleic anhydride-grafted polypropylene, the addition amount of potassium feldspar powder in maleic anhydride-grafted polypropylene is 17%.

[0124] After the concrete prepared in Examples 1 - 7 and Comparative Examples 1 - 8 has hardened for 28 days, refer to GB / T50081-2019 to test the compressive strength and elastic modulus of each concrete test piece, refer to GB / T25993-2010 to test the water permeability coefficient of each concrete test piece; refer to standard T / CECS 10107 to test the tensile strength of each concrete test piece; refer to standard DL / T 5332-2005, and use the three-point method to test the fracture toughness of each concrete test piece (the size of the test piece is 200mm×200mm×1000mm, and the precast crack is generated by embedding a steel plate, and the crack length is controlled within 80mm±2mm). The results are shown in Table 1:

[0125] Table 1

[0126]

[0127] It can be seen from the data in Table 1 that:

[0128] 1), The compressive strength of the high-toughness concrete decorative bricks prepared by the present invention is all above 140 MPa, the tensile strength is all above 15 MPa, the fracture toughness is all above 30 KJ / m 2 above, and the water permeability coefficient is less than 1.7 mm / s; that is, the high-toughness concrete decorative bricks prepared by the present invention have both high compressive strength and high toughness, and have good anti-permeability coefficient.

[0129] 2), Both the nano-clay and the modified fiber-reinforced polypropylene in the present invention have a great influence on the fracture toughness of the prepared high-toughness concrete decorative bricks, and the modified fiber-reinforced polypropylene has a greater influence. At the same time, the modified fiber-reinforced polypropylene also has a great influence on the compressive strength of the high-toughness concrete decorative bricks.

[0130] 3), The potassium feldspar powder in the nano-clay of the present invention has a great influence on the fracture toughness of the prepared high-toughness concrete decorative brick. Compared with adding pure bentonite, the nano-clay containing potassium feldspar powder and bentonite in the present invention significantly improves the fracture toughness of the high-toughness concrete decorative brick.

[0131] 4), By adding modified fiber-reinforced polypropylene in the present invention, compared with adding steel fibers, the compressive strength and fracture toughness of the prepared high-toughness concrete decorative brick are significantly improved. At the same time, the water permeability coefficient is also improved.

[0132] 5), During the preparation of modified fiber-reinforced polypropylene, whether potassium feldspar powder is added and the addition amount of potassium feldspar powder will affect the compressive strength and fracture toughness of the prepared high-toughness concrete decorative brick.

[0133] 6), Modified potassium feldspar powder can further improve the compressive strength and fracture toughness of concrete.

[0134] The specific embodiments described above further elaborate on the purpose, technical solutions, and beneficial effects of the present invention. It should be understood that the above description is only the specific embodiments of the present invention and is not used to limit the protection scope of the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A high-toughness concrete decorative brick, characterized in that: It includes the following components by weight: 500-600 parts of cement, 120-150 parts of nano clay, 80-100 parts of modified fiber reinforced polypropylene, 1000-1200 parts of aggregate, 3-5 parts of water reducer, 100-200 parts of water; The fibers used in the modified fiber reinforced polypropylene are glass fibers and carbon fibers; the polypropylene used in the modified fiber reinforced polypropylene is maleic anhydride grafted polypropylene, and potassium feldspar powder is added to the maleic anhydride grafted polypropylene; Wherein, the nanoclay is a mixture of bentonite powder and potassium feldspar powder; The potassium feldspar powder is a modified potassium feldspar powder; the preparation process of the modified potassium feldspar powder is as follows: The potassium feldspar powder is mixed with activated carbon powder for 30-60 minutes, wherein the particle size of the activated carbon powder is smaller than that of the potassium feldspar powder, and then the activated carbon powder is removed by sieving, and then the potassium feldspar powder is mixed with smithsonite powder and calcium carbonate powder and ball milled for 30 minutes, wherein the amount of the smithsonite powder is 10%, the amount of the activated carbon powder is 5%, and the amount of the calcium carbonate powder is 8% based on the weight of the potassium feldspar powder; The weight ratio of the bentonite powder to the potassium feldspar powder is (3-4):1; The preparation process of the modified fiber reinforced polypropylene is as follows: Firstly, the glass fiber and the carbon fiber are surface treated with nano-silicon dioxide respectively, and then the surface treated glass fiber and the carbon fiber are mixed, and then the mixed fibers are mixed with the maleic anhydride grafted polypropylene, and then the modified fiber reinforced polypropylene is obtained by extrusion process; The amount of the potassium feldspar powder added to the maleic anhydride grafted polypropylene is 12-15% by weight.

2. The high-toughness concrete decorative brick according to claim 1, characterized in that: The aggregate includes coarse aggregate and fine aggregate; the particle size of the coarse aggregate is (2.5-2.0) mm, and the particle size of the fine aggregate is (0.5-0.8) mm; the weight ratio of the coarse aggregate to the fine aggregate is 1:(0.5-0.6).

3. The high-toughness concrete decorative brick according to claim 1, characterized in that: The high-toughness concrete decorative brick also includes 30-50 parts of mineral admixture; the mineral admixture is a mixture of fly ash and slag powder, and the weight ratio of the fly ash to the slag powder is (2-3):

1.

4. A high-toughness concrete decorative brick according to any one of claims 1 to 3, characterized in that: The water-to-cement ratio of the high-toughness concrete decorative brick is (0.20-0.25).

5. The method for preparing the high-toughness concrete decorative brick according to any one of claims 1 to 4, characterized in that: The following steps are involved: S1, preparing the modified fiber reinforced polypropylene: S11, firstly surface-treating the glass fiber and the carbon fiber respectively with nano-silicon dioxide; S12, mixing the glass fiber and the carbon fiber processed in step S11 at a weight ratio of 3:1, wherein the length of the glass fiber and the carbon fiber are both 15-20 mm; S13, dispersing the potassium feldspar powder in the maleic anhydride grafted polypropylene, then uniformly mixing the mixed fiber and the maleic anhydride grafted polypropylene, putting them into an extruder for extrusion molding, cooling, and pelletizing to obtain the modified fiber reinforced polypropylene; S2. Add the cement, the nanoclay, the aggregate and the water reducing agent in proportion into a forced mixer and dry mix the mixture at a speed of 35-45 r / min for 3-4 minutes. After adding the water for fluidized stirring for 3-4 minutes, add the modified fiber reinforced polypropylene and continue stirring for 4-5 minutes to obtain concrete. Pour the concrete into a mold and cure it to obtain high-toughness concrete decorative tiles.

6. The preparation method according to claim 5, characterized in that: The weight ratio of the mixed fibers in the modified fiber reinforced polypropylene to the maleic anhydride grafted polypropylene is (2-3): (3-5).

7. The preparation method according to claim 5, characterized in that: The amount of the potassium feldspar powder added to the maleic anhydride grafted polypropylene is 12-15% by weight.

8. The use of the high-toughness concrete decorative brick according to any one of claims 1 to 4, characterized in that: The products used for preparation include decorative walls or floors.

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