Geopolymer-based permeable concrete material and preparation method

Abstract

The present invention belongs to the technical field of permeable concrete materials for sponge cities and discloses a geopolymer-based permeable concrete material and preparation method. The permeable concrete material comprises component A and component B; component A comprises a composite alkali activator and chitin; and component B comprises calcined metakaolin, Portland cement, water, a water reducer, a silane coupling agent, nano-silica, a nano-titanium dioxide aqueous solution, calcium chloride, a silicone-acrylic emulsion, and quartz sand. The concrete material of the present invention has high permeability, good wear resistance, high early strength, good durability, water purification and alkali inhibition, is easy to construct, has a short curing time, and is reasonably priced, effectively meeting the performance requirements of permeable concrete.

Description

Technical Field

[0001] The present invention belongs to the technical field of sponge city permeable concrete materials, and more specifically, relates to a geopolymer-based permeable concrete material and a preparation method. Background Art

[0002] Modern urban construction has led to increased urban heat. The three-dimensional nature of cities has reduced heat dissipation, and the prevalence of impermeable hardened pavements such as cement concrete and asphalt concrete has reduced water infiltration and evaporation, leading to a series of urban ecological problems, such as the heat island effect and urban waterlogging. To improve the urban ecological environment, the concept of sponge city construction has emerged. Permeable surfaces are key to addressing these ecological challenges, and permeable cement concrete is a pavement material currently undergoing extensive research. However, traditional permeable cement concrete is prone to pore clogging during service, significantly reducing its permeability. Furthermore, permeable cement concrete also suffers from drawbacks such as long curing and maintenance times. Therefore, the development of new, high-performance permeable concrete materials is urgent. Summary of the Invention

[0003] The present invention addresses the shortcomings of existing technologies by providing a geopolymer-based permeable concrete material and preparation method. The concrete material of the present invention features high water permeability, good wear resistance, high early strength, good durability, water purification and alkali inhibition, ease of construction, a short curing time, and reasonable price, effectively meeting the performance requirements of permeable concrete.

[0004] In order to achieve the above-mentioned object, the present invention provides a geopolymer-based permeable concrete material in one aspect, wherein the permeable concrete material comprises component A and component B;

[0005] The A component includes a composite alkali activator and chitin;

[0006] The B component comprises calcined metakaolin, silicate cement, water, water reducing agent, silane coupling agent, nano silicon dioxide, nano titanium dioxide aqueous solution, calcium chloride, silicone acrylic emulsion and quartz sand.

[0007] According to the present invention, preferably, the component A comprises the following components in parts by weight: 2.5 to 6 parts of a composite alkali activator and 0.5 to 2.5 parts of chitin;

[0008] The B component includes the following components in parts by weight: 4.5-10 parts of calcined metakaolin, 3-6 parts of Portland cement, 4-7 parts of water, 0.05-0.5 parts of water reducer, 0.4-1.0 parts of silane coupling agent, 0.5-3 parts of nano-silicon dioxide, 0.5-5 parts of nano-titanium dioxide aqueous solution, 0.5-3 parts of calcium chloride, 1.5-5 parts of silicone acrylic emulsion and 60-80 parts of quartz sand.

[0009] According to the present invention, preferably, the component A comprises the following components in parts by weight: 3 to 5 parts of a composite base activator and 1 to 2 parts of chitin;

[0010] The B component includes the following components in parts by weight: 5-7 parts of calcined metakaolin, 4-6 parts of Portland cement, 4-7 parts of water, 0.1-0.5 parts of water reducer, 0.5-1.0 parts of silane coupling agent, 1-2 parts of nano-silicon dioxide, 1-5 parts of nano-titanium dioxide aqueous solution, 1-2 parts of calcium chloride, 2-5 parts of silicone acrylic emulsion and 65-75 parts of quartz sand.

[0011] According to the present invention, preferably, the composite alkali activator is a mixture of NaOH and Na2SiO3 aqueous solution, the modulus of the composite alkali activator is 1.1-1.5M, and the aging time of the composite alkali activator is ≥4h.

[0012] According to the present invention, preferably, the solid content of the Na2SiO3 aqueous solution is 30-40%.

[0013] According to the present invention, preferably, the Portland cement is 32.5 Portland cement and / or 42.5 Portland cement.

[0014] According to the present invention, preferably, the silane coupling agent is KH550 and / or KH560.

[0015] According to the present invention, preferably, the particle size of the nano-silicon dioxide is 95 to 105 nm.

[0016] According to the present invention, preferably, the nano-titanium dioxide aqueous solution has a solid content of 5 to 15% and a solid particle size of 95 to 105 nm.

[0017] According to the present invention, preferably, the particle size of the quartz sand is 2 to 4 mm.

[0018] According to the present invention, preferably, the nano-titanium dioxide aqueous solution is a nano-titanium dioxide aqueous solution prepared using sodium tripolyphosphate as a dispersant.

[0019] According to the present invention, preferably, the ratio of component A to component B is (0.1-1):1.

[0020] Another aspect of the present invention provides a method for preparing the geopolymer-based permeable concrete material, the method comprising:

[0021] S1: mixing the composite alkali activator and chitosan to obtain the component A;

[0022] S2: ball-milling the calcined metakaolin, nano-silica, calcium chloride, Portland cement, and quartz sand to obtain a premix; and uniformly mixing the premix, water, a water reducer, a nano-titanium dioxide aqueous solution, a silicone-acrylic emulsion, and a silane coupling agent to obtain component B;

[0023] S3: Mixing and stirring the component A and the component B uniformly to obtain the geopolymer-based permeable concrete material.

[0024] According to the present invention, preferably, in step S2:

[0025] The equipment for performing the mixed ball milling is a planetary ball mill, and the time for the mixed ball milling is 10-20 minutes;

[0026] The mixing time is 1-2 minutes.

[0027] The beneficial effects of the technical solution of the present invention are as follows:

[0028] 1) The geopolymer-based permeable concrete material of the present invention has the characteristics of high water permeability, good wear resistance, high early strength, good durability, water purification and alkali inhibition, easy construction, short curing time and moderate price, and can better meet the performance requirements of permeable concrete.

[0029] 2) The preparation method of the geopolymer permeable pavement material of the present invention is simple and easy to promote.

[0030] Other features and advantages of the present invention will be described in detail in the following detailed description. DETAILED DESCRIPTION

[0031] The preferred embodiments of the present invention will be described in more detail below. Although the preferred embodiments of the present invention are described below, it should be understood that the present invention can be implemented in various forms and should not be limited by the embodiments set forth herein. Instead, these embodiments are provided to make the present invention more thorough and complete and to fully convey the scope of the present invention to those skilled in the art.

[0032] In the following embodiments:

[0033] The composite alkali activator is a mixture of NaOH and Na2SiO3 aqueous solution (solid content is 35%), the modulus of the composite alkali activator is 1.2M, and the aging time of the composite alkali activator is ≥4h;

[0034] The Portland cement is 32.5 Portland cement;

[0035] The silane coupling agent is KH550;

[0036] The particle size of the nano-silicon dioxide is 95 to 105 nm;

[0037] The nano titanium dioxide aqueous solution is a nano titanium dioxide aqueous solution prepared by using sodium tripolyphosphate as a dispersant, the nano titanium dioxide aqueous solution has a solid content of 10%, and a solid particle size of 95 to 105 nm;

[0038] The particle size of the quartz sand is 2 to 4 mm.

[0039] Example 1

[0040] This embodiment provides a geopolymer-based permeable concrete material, the permeable concrete material comprising component A and component B;

[0041] The component A comprises the following components in parts by weight: 3 parts of a composite alkali activator and 2 parts of chitin;

[0042] The B component includes the following components in parts by weight: 5 parts of calcined metakaolin, 4 parts of Portland cement, 4 parts of water, 0.1 parts of water reducer, 0.5 parts of silane coupling agent, 1 part of nano silicon dioxide, 1 part of nano titanium dioxide aqueous solution, 2 parts of calcium chloride, 2 parts of silicone acrylic emulsion and 65 parts of quartz sand.

[0043] The preparation method of the above-mentioned geopolymer-based permeable concrete material includes:

[0044] S1: mixing the composite alkali activator and chitosan to obtain the component A;

[0045] S2: Grinding the calcined metakaolin, nano-silicon dioxide, calcium chloride, Portland cement, and quartz sand in a planetary ball mill for 15 minutes to obtain a premix;

[0046] In a concrete mixer, the premix, water, water reducing agent, nano titanium dioxide aqueous solution, silicone acrylic emulsion and silane coupling agent are mixed and stirred for 1-2 minutes to obtain the B component;

[0047] S2: The component A and the component B are mixed and stirred evenly, poured, vibrated, and cured for 28 days under standard conditions (i.e., temperature of (20±2)°C and relative humidity of (95%) or above) to obtain the geopolymer-based permeable concrete pavement material.

[0048] Examples 2-6

[0049] Examples 2-6 respectively provide a geopolymer-based permeable concrete material. The difference between Examples 2-6 and Example 1 is that the amounts of each component are different, see Table 1 for details.

[0050] Table 1

[0051]

[0052]

[0053] Test Example 1

[0054] This test example tests the performance of the geopolymer-based permeable concrete materials in Examples 1-6. The porosity test method refers to the "Technical Specification for Permeable Concrete Pavement (Beijing)" (DB11AT775-2010); the mechanical property test method refers to the "Standard for Test Methods of Mechanical Properties of Ordinary Concrete" (GBT50081-2002); the permeability coefficient is measured and calculated based on Darcy's law, Pb 2+ The maximum adsorption capacity was determined and calculated according to the "Solid Waste Leaching Toxicity Leaching Method Acetate Buffer Solution Method" (HJ / T300-2007). The test results are shown in Table 2.

[0055] Table 2

[0056]

[0057] While various embodiments of the present invention have been described above, the above description is intended to be illustrative, not exhaustive, and not limited to the disclosed embodiments. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments.

Claims

1. A geopolymer-based permeable concrete material, characterized in that: The permeable concrete material includes component A and component B; The component A comprises the following components in parts by weight: 2.5 to 6 parts of a composite alkali activator and 0.5 to 2.5 parts of chitin; The composite alkali activator is a mixture of NaOH and Na2SiO3 aqueous solution, the solid content of the Na2SiO3 aqueous solution is 30-40%, the modulus of the composite alkali activator is 1.1-1.5M, and the aging time of the composite alkali activator is ≥4h; The B component includes the following components in parts by weight: 4.5-10 parts of calcined metakaolin, 3-6 parts of Portland cement, 4-7 parts of water, 0.05-0.5 parts of a water reducer, 0.4-1.0 parts of a silane coupling agent, 0.5-3 parts of nano-silicon dioxide, 0.5-5 parts of a nano-titanium dioxide aqueous solution, 0.5-3 parts of calcium chloride, 1.5-5 parts of a silicone-acrylic emulsion, and 60-80 parts of quartz sand; The Portland cement is 32.5 Portland cement and / or 42.5 Portland cement; The nano-titanium dioxide aqueous solution has a solid content of 5-15% and a solid particle size of 95-105 nm; the nano-titanium dioxide aqueous solution is a nano-titanium dioxide aqueous solution prepared using sodium tripolyphosphate as a dispersant; The particle size of the quartz sand is 2-4 mm; The ratio of component A to component B is (0.1-1):1; The preparation method of the geopolymer-based permeable concrete material comprises: S1: mixing the composite alkali activator and chitosan to obtain the component A; S2: ball-milling the calcined metakaolin, nano-silica, calcium chloride, Portland cement, and quartz sand to obtain a premix; and uniformly mixing the premix, water, a water reducer, a nano-titanium dioxide aqueous solution, a silicone-acrylic emulsion, and a silane coupling agent to obtain component B; S3: Mixing and stirring the component A and the component B uniformly to obtain the geopolymer-based permeable concrete material.

2. The geopolymer-based permeable concrete material according to claim 1, wherein: The component A comprises the following components in parts by weight: 3 to 5 parts of a composite base activator and 1 to 2 parts of chitin; The B component includes the following components in parts by weight: 5-7 parts of calcined metakaolin, 4-6 parts of Portland cement, 4-7 parts of water, 0.1-0.5 parts of a water reducer, 0.5-1.0 parts of a silane coupling agent, 1-2 parts of nano-silicon dioxide, 1-5 parts of a nano-titanium dioxide aqueous solution, 1-2 parts of calcium chloride, 2-5 parts of a silicone-acrylic emulsion, and 65-75 parts of quartz sand.

3. The geopolymer-based permeable concrete material according to claim 1 or 2, wherein: The silane coupling agent is KH550 and / or KH560; The particle size of the nano-silicon dioxide is 95-105 nm.

4. The geopolymer-based permeable concrete material according to claim 1, wherein: In step S2: The equipment for performing the mixed ball milling is a planetary ball mill, and the time for the mixed ball milling is 10-20 minutes; The mixing time is 1-2 minutes.

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