A polymer permeable mortar for permeable paving bricks

Abstract

This application relates to a polymer permeable mortar for permeable paving bricks, belonging to the field of building materials technology. It comprises the following components in parts by weight: 80-100 parts silicate cement, 40-60 parts compatibilizing modified aggregate, 2-5 parts modified latex powder, 10-20 parts modified basalt fiber, 1-2 parts polycarboxylate superplasticizer, and 40-50 parts water. This application has the effect of improving the permeability, stability, and adhesion properties of the polymer permeable mortar.

Description

Technical Field

[0001] This application relates to the field of building materials technology, and in particular to a polymer permeable mortar for permeable paving bricks. Background Technology

[0002] With economic development and the accelerating pace of urban modernization, most cities are experiencing problems such as groundwater scarcity and the urban heat island effect. Research has found that these problems are related to the continuous covering of natural soil and vegetation with buildings and various impermeable surfaces during urban construction. In many Chinese cities, the proportion of impermeable surfaces has exceeded 70%, altering the original permeability of natural surfaces and severely damaging the ecological environment. In cities with high rainfall, if impermeable materials such as cement, asphalt, and marble are used for paving, they completely prevent rainwater from directly infiltrating the ground, leading to widespread flooding that inconveniences people and wastes precious water resources. This also burdens urban drainage systems, and the significant loss of rainwater further exacerbates urban drought and water shortages.

[0003] Using permeable paving bricks and splicing them together with permeable filler material is an effective way to solve the problem of water accumulation on roads. Currently, a relatively good permeable filler material is polymer permeable mortar. This mortar uses sand and gravel as aggregates, bonded together by a polymer. The pores between the aggregates provide channels for water permeability, and the polymer imparts good adhesion, flexibility, and a certain load-bearing capacity. However, in polymer permeable mortar, there is a difficult-to-reconcile contradiction between the amount of polymer and aggregate used in terms of bonding performance and permeability. When the amount of aggregate is small and the amount of polymer is large, the bonding strength is good, but the permeability will be significantly reduced, thus requiring further improvement. Summary of the Invention

[0004] In order to improve the permeability of polymer permeable mortar, this application provides a polymer permeable mortar for permeable paving bricks.

[0005] This application provides a polymer permeable mortar for permeable pavement bricks, employing the following technical solution:

[0006] A polymer permeable mortar for permeable paving bricks, comprising the following components in parts by weight:

[0007] 80-100 parts of silicate cement

[0008] 40-60 parts of volume-enhancing modified aggregate

[0009] 2-5 parts modified latex powder

[0010] 10-20 parts modified basalt fiber

[0011] 1-2 parts of polycarboxylate superplasticizer

[0012] 40-50 parts water.

[0013] Compatibilized modified aggregates, through compatibilization modification treatment, can improve the system compatibility of aggregates, thereby enhancing the stability and permeability of polymer permeable mortar. Modified latex powder has good dispersibility and can toughen polymer permeable mortar, improving its bonding and permeability. Modified basalt fiber, through modification treatment, has good dispersibility and system compatibility, which can improve the freeze-thaw resistance of polymer permeable mortar, thereby enhancing its stability and permeability.

[0014] Preferably, the raw materials for preparing the compatibilized modified aggregate include aggregate, acrylamide, and dopamine.

[0015] Acrylamide and dopamine can be cross-linked and polymerized to obtain a mixed polymer of polyacrylamide and polydopamine, which has good adhesion properties and system compatibility. It can improve the bonding force between the compatibilized modified aggregate and the cement interface, and improve the strength of the transition zone between aggregate and cement, thereby improving the adhesion, stability and permeability of polymer permeable mortar.

[0016] Preferably, the mass ratio of the aggregate, acrylamide and dopamine is 1:0.2:(0.1-0.15).

[0017] The compost-modified aggregate prepared according to the above mass ratio has good adhesion, stability and permeability.

[0018] Preferably, the raw materials for preparing the modified latex powder include mixed monomers, n-butyl acrylate, and allyltriethoxysilane.

[0019] Mixed monomers, n-butyl acrylate, and allyltriethoxysilane can react to form latex powder particles with n-butyl acrylate as the core and mixed monomers as the shell. Allyltriethoxysilane, as a functional crosslinking monomer, can improve the stability and crosslinking ability of modified latex powder, further improve the dispersibility and system compatibility of modified latex powder, thereby improving the adhesion, stability, and permeability of polymer permeable mortar.

[0020] Preferably, the mass ratio of the mixed monomer, n-butyl acrylate and allyltriethoxysilane is 1:1.5:(0.3-0.4).

[0021] The modified latex powder prepared according to the above mass ratio has good dispersibility and stability.

[0022] Preferably, the mixed monomers include vinyl acetate and styrene.

[0023] By using styrene to partially replace vinyl acetate to obtain mixed monomers, the water resistance of modified latex powder can be improved, thereby enhancing the stability and permeability of polymer permeable mortar.

[0024] Preferably, the modified basalt fiber comprises basalt fiber, nano-silicon nitride, and compatibilizer.

[0025] Nano-silicon nitrides adhere to the surface of basalt fibers through reaction, which can enhance the bonding force between basalt fibers and polymer molecules, and provide groups and sites for cross-linking reactions. Compatibilizers further increase the surface active sites of modified basalt fibers by reacting with nano-silicon nitrides, thereby improving the system compatibility of modified basalt fibers and thus improving the adhesion, stability and permeability of polymer permeable mortar.

[0026] Preferably, the nano-silicon nitride is supported on basalt fibers, and the raw materials for preparing the nano-silicon nitride are vinyltrimethoxysilane and hexamethyldisilazane.

[0027] A silicon-based polymer with silicon-oxygen and silicon-nitrogen structures was obtained by reacting vinyltrimethoxysilane and hexamethyldisilazane. This polymer has abundant active sites and improves the adhesion properties of modified basalt fibers.

[0028] Preferably, the compatibilizer is maleic anhydride.

[0029] Maleic anhydride has good reactivity and compatibility, which can further increase the surface active sites of modified basalt fibers and improve the adhesion and permeability of polymer permeable mortar.

[0030] Preferably, the polymer permeable mortar is prepared using the following steps:

[0031] Silicate cement, compatibilizing modified aggregate, modified latex powder, modified basalt fiber, polycarboxylate superplasticizer and water are mixed and stirred to obtain polymer permeable mortar.

[0032] The polymer permeable mortar prepared according to the above steps has good adhesion, stability and permeability.

[0033] In summary, this application includes at least one of the following beneficial technical effects:

[0034] 1. Compatibilized modified aggregates: Through compatibilization modification, the system compatibility of aggregates can be improved, thereby enhancing the stability and permeability of polymer permeable mortar. Modified latex powder has good dispersibility and can toughen polymer permeable mortar, improving its bonding and permeability. Modified basalt fiber, through modification, has good dispersibility and system compatibility, which can improve the freeze-thaw resistance of polymer permeable mortar, thereby enhancing its stability and permeability.

[0035] 2. The modified aggregates, modified latex powder, and modified basalt fibers have increased surface active sites and improved crosslinking performance through modification treatment, thereby enhancing the adhesion and stability of polymer permeable mortar. Detailed Implementation

[0036] This application discloses a polymer permeable mortar for permeable pavement bricks. The following detailed description is based on the embodiments:

[0037] Example 1

[0038] Preparation of compostable modified aggregates

[0039] 15.39 kg of acrylamide (CAS No.: 79-06-1) and 0.01 kg of ammonium persulfate were mixed and dispersed in 20 L of water and stirred at 200 r / min for 2 h to obtain an acrylamide prepolymer. 7.69 kg of dopamine (CAS No.: 51-61-6) and 0.5 L of 30% hydrogen peroxide solution were added to the acrylamide prepolymer to obtain a mixed reaction solution. The pH of the mixed reaction solution was adjusted to 9 using a 1 mol / L sodium hydroxide aqueous solution and stirred at 300 r / min for 2 h to obtain a mixed prepolymer. 76.92 kg of aggregate was added to the mixed prepolymer and stirred at 50 r / min for 1 h. After air drying, the compatibilized modified aggregate was obtained.

[0040] Preparation of modified latex powder

[0041] Weigh out 5.36 kg of n-butyl acrylate (CAS No.: 141-32-2), 1.07 kg of allyltriethoxysilane (CAS No.: 2550-04-1), and 3.57 kg of mixed monomers, including 2.5 kg of vinyl acetate (CAS No.: 108-05-4) and 1.07 kg of styrene. Mix 30% of the total amount of n-butyl acrylate and 50% of the total amount of allyltriethoxysilane in 20 L of deionized water, add 0.02 kg of potassium persulfate and 0.01 kg of emulsifier, and stir at 200 r / min for 30 min in an 80°C water bath to obtain a preliminary polymerization seed solution. Add the remaining n-butyl acrylate and 0.5 L of 0.1 mol / L potassium persulfate aqueous solution dropwise to the preliminary polymerization seed solution over 30 min. Then, maintain the reaction temperature at 80°C for 30 min to obtain the seed solution.

[0042] The above-weighed mixed monomers, 50% of the total amount of allyltriethoxysilane, 0.15 kg of potassium persulfate, and 0.02 kg of emulsifier were mixed and dispersed in 10 L of deionized water to obtain a mixed dispersion. The mixed reaction solution was added dropwise to the seed solution, and the dropping rate was controlled under the condition of 80 °C in a water bath. The addition was completed within 2 hours, followed by keeping it at the temperature for 1 hour. After cooling to 30 °C, the mixture was filtered to obtain a preliminary product. The preliminary product was spray-dried using a spray dryer to obtain modified latex powder.

[0043] Preparation of modified basalt fibers

[0044] 50 kg of basalt fiber, 10 kg of vinyltrimethoxysilane (CAS No.: 2768-02-7), and 5 kg of hexamethyldisilazane (CAS No.: 999-97-3) were mixed and dispersed in 100 L of anhydrous ethanol to obtain a modified suspension. 2 kg of 1 mol / L ammonia water was added to the modified suspension, and the mixture was reacted at 200 r / min for 2 h in a water bath at 30 °C to obtain a modified suspension after reaction. 1 mol / L hydrochloric acid was added to the modified suspension to adjust the pH to 6, and the mixture was filtered to obtain a modified product. The modified product was calcined at 200 °C for 3 h to obtain a solid. The solid was ground to obtain a preliminary product. The preliminary product was mixed with 5 kg of maleic anhydride (CAS No.: 108-31-6) and reacted at 150 °C for 1 h to obtain modified basalt fiber.

[0045] Preparation of polymer permeable mortar

[0046] Mix 80 kg of silicate cement, 40 kg of compatibilizing modified aggregate, 2 kg of modified latex powder, 10 kg of modified basalt fiber, 1 kg of polycarboxylate superplasticizer and 40 kg of water, and stir at 300 r / min for 1 h to obtain polymer permeable mortar.

[0047] Example 2

[0048] Preparation of compostable modified aggregates

[0049] 14.82 kg of acrylamide and 0.01 kg of ammonium persulfate were mixed and dispersed in 20 L of water and stirred at 200 r / min for 2 h to obtain an acrylamide prepolymer. 11.11 kg of dopamine and 0.5 L of 30% hydrogen peroxide solution were added to the acrylamide prepolymer to obtain a mixed reaction solution. The pH of the mixed reaction solution was adjusted to 9 using a 1 mol / L sodium hydroxide aqueous solution and stirred at 300 r / min for 2 h to obtain a mixed prepolymer. 74.07 kg of aggregate was added to the mixed prepolymer and stirred at 50 r / min for 1 h. After air drying, the compatibilized modified aggregate was obtained.

[0050] Preparation of modified latex powder

[0051] Weigh out 5.17 kg of n-butyl acrylate, 1.38 kg of allyltriethoxysilane, and 3.45 kg of mixed monomers, including 2.42 kg of vinyl acetate and 1.04 kg of styrene. Mix 30% of the total amount of n-butyl acrylate and 50% of the total amount of allyltriethoxysilane in 20 L of deionized water, add 0.02 kg of potassium persulfate and 0.01 kg of emulsifier, and stir at 200 r / min for 30 min in an 80°C water bath to obtain a preliminary polymerization seed solution. Add the remaining n-butyl acrylate and 0.5 L of a 0.1 mol / L potassium persulfate aqueous solution dropwise to the preliminary polymerization seed solution over 30 min. Then, maintain the temperature at 80°C for 30 min to obtain the seed solution.

[0052] The above-weighed mixed monomers, 50% of the total amount of allyltriethoxysilane, 0.15 kg of potassium persulfate, and 0.02 kg of emulsifier were mixed and dispersed in 10 L of deionized water to obtain a mixed dispersion. The mixed reaction solution was added dropwise to the seed solution, and the dropping rate was controlled under the condition of 80 °C in a water bath. The addition was completed within 2 hours, followed by keeping it at the temperature for 1 hour. After cooling to 30 °C, the mixture was filtered to obtain a preliminary product. The preliminary product was spray-dried using a spray dryer to obtain modified latex powder.

[0053] Preparation of modified basalt fibers

[0054] 50 kg of basalt fiber, 10 kg of vinyltrimethoxysilane, and 5 kg of hexamethyldisilazane were mixed and dispersed in 100 L of anhydrous ethanol to obtain a modified suspension. 2 kg of 1 mol / L ammonia water was added to the modified suspension, and the mixture was reacted at 200 r / min for 2 h in a water bath at 30 °C to obtain a modified suspension after reaction. 1 mol / L hydrochloric acid was added to the modified suspension to adjust the pH to 6, and the mixture was filtered to obtain the modified product. The modified product was calcined at 200 °C for 3 h to obtain a solid. The solid was ground to obtain a preliminary product. The preliminary product was mixed with 5 kg of maleic anhydride and reacted at 150 °C for 1 h to obtain modified basalt fiber.

[0055] Preparation of polymer permeable mortar

[0056] Mix 100 kg of silicate cement, 60 kg of compatibilizing modified aggregate, 5 kg of modified latex powder, 20 kg of modified basalt fiber, 2 kg of polycarboxylate superplasticizer and 50 kg of water, and stir at 300 r / min for 1 h to obtain polymer permeable mortar.

[0057] Example 3

[0058] Preparation of compostable modified aggregates

[0059] 15.09 kg of acrylamide and 0.01 kg of ammonium persulfate were mixed and dispersed in 20 L of water and stirred at 200 r / min for 2 h to obtain an acrylamide prepolymer. 9.44 kg of dopamine and 0.5 L of 30% hydrogen peroxide solution were added to the acrylamide prepolymer to obtain a mixed reaction solution. The pH of the mixed reaction solution was adjusted to 9 using a 1 mol / L sodium hydroxide aqueous solution and stirred at 300 r / min for 2 h to obtain a mixed prepolymer. 75.47 kg of aggregate was added to the mixed prepolymer and stirred at 50 r / min for 1 h. After air drying, the compatibilized modified aggregate was obtained.

[0060] Preparation of modified latex powder

[0061] Weigh out 5.26 kg of n-butyl acrylate, 1.23 kg of allyltriethoxysilane, and 3.51 kg of mixed monomers, including 2.46 kg of vinyl acetate and 1.05 kg of styrene. Mix 30% of the total amount of n-butyl acrylate and 50% of the total amount of allyltriethoxysilane in 20 L of deionized water, add 0.02 kg of potassium persulfate and 0.01 kg of emulsifier, and stir at 200 r / min for 30 min in a water bath at 80 °C to obtain a preliminary polymerization seed solution. Add the remaining n-butyl acrylate and 0.5 L of 0.1 mol / L potassium persulfate aqueous solution dropwise to the preliminary polymerization seed solution over 30 min. Then, maintain the temperature at 80 °C for 30 min to obtain the seed solution.

[0062] The above-weighed mixed monomers, 50% of the total amount of allyltriethoxysilane, 0.15 kg of potassium persulfate, and 0.02 kg of emulsifier were mixed and dispersed in 10 L of deionized water to obtain a mixed dispersion. The mixed reaction solution was added dropwise to the seed solution, and the dropping rate was controlled under the condition of 80 °C in a water bath. The addition was completed within 2 hours, followed by keeping it at the temperature for 1 hour. After cooling to 30 °C, the mixture was filtered to obtain a preliminary product. The preliminary product was spray-dried using a spray dryer to obtain modified latex powder.

[0063] Preparation of modified basalt fibers

[0064] 50 kg of basalt fiber, 10 kg of vinyltrimethoxysilane, and 5 kg of hexamethyldisilazane were mixed and dispersed in 100 L of anhydrous ethanol to obtain a modified suspension. 2 kg of 1 mol / L ammonia water was added to the modified suspension, and the mixture was reacted at 200 r / min for 2 h in a water bath at 30 °C to obtain a modified suspension after reaction. 1 mol / L hydrochloric acid was added to the modified suspension to adjust the pH to 6, and the mixture was filtered to obtain the modified product. The modified product was calcined at 200 °C for 3 h to obtain a solid. The solid was ground to obtain a preliminary product. The preliminary product was mixed with 5 kg of maleic anhydride and reacted at 150 °C for 1 h to obtain modified basalt fiber.

[0065] Preparation of polymer permeable mortar

[0066] 90 kg of silicate cement, 50 kg of compatibilizing modified aggregate, 3.5 kg of modified latex powder, 15 kg of modified basalt fiber, 1.5 kg of polycarboxylate superplasticizer and 45 kg of water are mixed and stirred at 300 r / min for 1 h to obtain polymer permeable mortar.

[0067] Example 4

[0068] Example 4 is based on Example 3. The only difference between Example 4 and Example 3 is that the amount of aggregate used in Example 4 is 80 kg, the amount of acrylamide is 16 kg, and the amount of dopamine is 4 kg.

[0069] Example 5

[0070] Example 5 is based on Example 3. The only difference between Example 5 and Example 3 is that the amount of aggregate used in Example 5 is 71.42 kg, the amount of acrylamide used is 14.29 kg, and the amount of dopamine used is 14.29 kg.

[0071] Example 6

[0072] Example 6 is based on Example 3. The only difference between Example 6 and Example 3 is that in Example 6, the amount of mixed monomers is 3.7 kg, the amount of n-butyl acrylate is 5.56 kg, the amount of allyltriethoxysilane is 0.74 kg, the amount of vinyl acetate in the mixed monomers is 2.59 kg, and the amount of styrene is 1.11 kg.

[0073] Example 7

[0074] Example 7 is based on Example 3. The only difference between Example 7 and Example 3 is that in Example 7, the amount of mixed monomers is 3.7 kg, the amount of n-butyl acrylate is 5.56 kg, the amount of allyltriethoxysilane is 0.74 kg, the amount of vinyl acetate in the mixed monomers is 2.59 kg, and the amount of styrene is 1.11 kg.

[0075] Example 8

[0076] Example 8 is based on Example 3. The only difference between Example 8 and Example 3 is that in Example 8, acrylamide in the step of preparing compatibilized modified aggregate is replaced with acrylic acid.

[0077] Example 9

[0078] Example 9 is based on Example 3. The only difference between Example 9 and Example 3 is that in Example 9, dopamine in the preparation step of compatibilized modified aggregate is replaced with tannic acid.

[0079] Example 10

[0080] Example 10 is based on Example 3. The only difference between Example 10 and Example 3 is that in Example 10, allyltriethoxysilane in the step of preparing modified latex powder is replaced with methyltriethoxysilane.

[0081] Example 11

[0082] Example 11 is based on Example 3. The only difference between Example 11 and Example 3 is that in Example 11, the mixed monomers in the step of preparing modified latex powder are replaced with vinyl acetate.

[0083] Example 12

[0084] Example 12 is based on Example 3. The only difference between Example 12 and Example 3 is that in Example 12, hexamethyldisilazane in the step of preparing modified basalt fiber is replaced with methyltriethoxysilane.

[0085] Example 13

[0086] Example 13 is based on Example 3. The only difference between Example 13 and Example 3 is that maleic anhydride is not added in the step of preparing modified basalt fiber in Example 13.

[0087] Comparative Example 1

[0088] Comparative Example 1 is based on Example 3. The only difference between Comparative Example 1 and Example 3 is that the compatibilized modified aggregate is replaced with aggregate in Comparative Example 1.

[0089] Comparative Example 2

[0090] Comparative Example 2 is based on Example 3. The only difference between Comparative Example 2 and Example 3 is that the modified latex powder is replaced with redispersible latex powder in Comparative Example 2.

[0091] Comparative Example 3

[0092] Comparative Example 3 is based on Example 3. The only difference between Comparative Example 3 and Example 3 is that the modified basalt fiber is replaced with basalt fiber in Comparative Example 3.

[0093] Performance testing

[0094] Using JCT 2727-2022 Permeable Mortar as the standard, three 100mm*100mm*100mm samples were prepared, and their permeability coefficient was tested at 15℃; six 70.7mm*70.7mm*70.7mm samples were prepared, and their 28-day compressive strength was tested; three 40mm*40mm*160mm samples were prepared, and their 28-day flexural strength was tested; twelve 70.7mm*70.7mm*70.7mm samples were prepared, and their frost resistance was tested; and ten 40mm*40mm*6mm samples were prepared, and their 14-day tensile bond strength was tested. Each sample was tested three times, and the average value was taken. The results are recorded in Table 1.

[0095] Table 1. Test results of permeability, stability and bonding properties of polymer permeable mortar

[0096]

[0097] As shown in Table 1, the permeability coefficient of Examples 1-3 is greater than 12.3 mm / s, the compressive strength is greater than 35.6 MPa, the flexural strength is greater than 7.5 MPa, the number of freeze-thaw cycles is greater than 153, and the bonding strength is greater than 1.3 MPa. This shows that the polymer permeable mortar has good permeability, stability and bonding performance.

[0098] As shown in Table 1, the only difference between Examples 4, 5, and 3 is that the mass ratio of aggregate, acrylamide, and dopamine in Example 4 is 1:0.2:0.05, and the mass ratio of aggregate, acrylamide, and dopamine in Example 5 is 1:0.2:0.2. The permeability coefficient, compressive strength, flexural strength, and number of freeze-thaw cycles in Examples 4 and 5 are less than 12.1 mm / s, less than 35.2 MPa, less than 7.0 MPa, less than 147, and less than 1.2 MPa. Compared with Example 3, the permeability, stability, and adhesion properties of Examples 4 and 5 have all decreased. This is because the mass ratio of aggregate, acrylamide, and dopamine is not within the specified range. Too much or too little dopamine will affect the compatibility of the modified aggregate system, and the reaction performance between the components of the polymer permeable mortar will decrease. Therefore, the permeability, stability, and adhesion properties have all decreased.

[0099] As shown in Table 1, the only difference between Examples 6 and 7 and Example 3 is that the mass ratio of the mixed monomer, n-butyl acrylate, and allyltriethoxysilane in Example 6 is 1:1.5:0.2, and the mass ratio of the mixed monomer, n-butyl acrylate, and allyltriethoxysilane in Example 7 is 1:1.5:0.5. The permeability coefficient of Examples 6 and 7 is less than 11.9 mm / s, the compressive strength is less than 34.1 MPa, the flexural strength is less than 6.8 MPa, the number of freeze-thaw cycles is less than 141, and the adhesive strength is less than 1.2 MPa. Compared with Example 3, the permeability, stability, and adhesion properties of Examples 6 and 7 have all decreased. This is because the mass ratio of the mixed monomer, n-butyl acrylate, and allyltriethoxysilane is not within the specified range. Too much or too little allyltriethoxysilane will affect the stability and reactivity of the modified latex powder, and the system compatibility of the modified latex powder will decrease. Therefore, the permeability, stability, and adhesion properties have all decreased.

[0100] As shown in Table 1, the only difference between Examples 8 and 9 and Example 3 is that in Example 8, acrylamide in the preparation step of compatibilized modified aggregate was replaced with acrylic acid, and in Example 9, dopamine in the preparation step of compatibilized modified aggregate was replaced with tannic acid. The permeability coefficient of Examples 8 and 9 is less than 11.1 mm / s, the compressive strength is less than 30.5 MPa, the flexural strength is less than 5.9 MPa, the number of freeze-thaw cycles is less than 131, and the bonding strength is less than 0.9 MPa. Compared with Example 3, the permeability, stability, and adhesion properties of Examples 8 and 9 have all decreased. This is because the components of the compatibilized modified aggregate have been replaced. Acrylic acid or tannic acid has lower adhesion and reactivity than acrylamide or dopamine, and the dispersibility and compatibility of the compatibilized modified aggregate in the system are reduced. Therefore, the permeability, stability, and adhesion properties have all decreased.

[0101] As shown in Table 1, the only difference between Examples 10 and 11 and Example 3 is that in Example 10, allyltriethoxysilane in the step of preparing modified latex powder was replaced with methyltriethoxysilane, and in Example 11, the mixed monomers in the step of preparing modified latex powder were replaced with vinyl acetate. The water permeability coefficient of Examples 10 and 11 was less than 10.7 mm / s, the compressive strength was less than 29.6 MPa, the flexural strength was less than 5.5 MPa, the number of freeze-thaw cycles was less than 126, and the adhesive strength was less than 0.8 MPa. Compared with Example 3, the water permeability, stability, and adhesion properties of Examples 10 and 11 all decreased. This is because replacing allyltriethoxysilane with methyltriethoxysilane reduces the reactivity of methyltriethoxysilane and weakens its reactivity. Replacing the mixed monomers with a single vinyl acetate reduces the stability and water resistance of the latex powder. Both of these factors affect the overall stability and dispersibility of the modified latex powder in the system, thus reducing the water permeability, stability, and adhesion properties.

[0102] As shown in Table 1, the only difference between Examples 12 and 13 and Example 3 is that in Example 12, hexamethyldisilazane in the step of preparing modified basalt fiber was replaced with methyltriethoxysilane; in Example 13, maleic anhydride was not added in the step of preparing modified basalt fiber. The permeability coefficient of Examples 12 and 13 is less than 9.2 mm / s, the compressive strength is less than 25.7 MPa, the flexural strength is less than 4.6 MPa, the number of freeze-thaw cycles is less than 111, and the bonding strength is 0.6 MPa. Compared with Example 3, the permeability, stability, and adhesion properties of Examples 12 and 13 have all decreased. This is because replacing silazane with silane reduces the stability of the modified basalt fiber lacking a silicon-nitrogen structure, and not adding maleic anhydride reduces the system compatibility of the modified basalt fiber. Both of these factors reduce the stability of the polymer permeable mortar, thus reducing the permeability, stability, and adhesion properties.

[0103] As shown in Table 1, the only difference between Comparative Example 1 and Example 3 is that the compatibilized modified aggregate was replaced with aggregate in Comparative Example 1. The permeability coefficient of Comparative Example 1 is 5.1 mm / s, the compressive strength is 15.8 MPa, the flexural strength is 2.7 MPa, the number of freeze-thaw cycles is 77, and the bond strength is 0.5 MPa. Compared with Example 3, Comparative Example 1 shows a significant decrease in permeability, stability, and adhesion performance. This is because replacing the compatibilized modified aggregate with aggregate lacks the surface treatment corresponding to the polymer, resulting in a decrease in the bonding force between the aggregate and cement interface and a reduction in the stability of the polymer permeable mortar. Therefore, the permeability, stability, and adhesion performance all show a significant decrease.

[0104] As shown in Table 1, the only difference between Comparative Example 2 and Example 3 is that the modified latex powder was replaced with redispersible latex powder in Comparative Example 2. The permeability coefficient of Comparative Example 2 was 6.7 mm / s, the compressive strength was 19.7 MPa, the flexural strength was 3.5 MPa, the number of freeze-thaw cycles was 94, and the adhesive strength was 0.6 MPa. Compared with Example 3, Comparative Example 2 showed a significant decrease in permeability, stability, and adhesion. This is because the modified latex powder was replaced with redispersible latex powder, which has fewer active groups than the modified latex powder and lacks the functional monomers to improve water resistance and stability. As a result, the compatibility and stability of the polymer permeable mortar system decreased, thus significantly reducing the permeability, stability, and adhesion.

[0105] As shown in Table 1, the only difference between Comparative Example 3 and Example 3 is that the modified basalt fiber was replaced with basalt fiber in Comparative Example 3. The permeability coefficient of Comparative Example 3 is 4.2 mm / s, the compressive strength is 11.9 MPa, the flexural strength is 2.1 MPa, the number of freeze-thaw cycles is 54, and the bonding strength is 0.3 MPa. Compared with Example 3, the permeability, stability, and adhesion performance of Comparative Example 3 are significantly reduced. This is because the surface of basalt fiber is smoother when the modified basalt fiber is replaced with basalt fiber, resulting in weaker bonding with other components in the polymer permeable mortar system and a decrease in the compatibility of the system. Therefore, the permeability, stability, and adhesion performance are significantly reduced.

[0106] This specific embodiment is merely an explanation of this application and is not intended to limit it. Based on the above description, those skilled in the art can make various changes and modifications without departing from the technical concept of this application. The technical scope of this application is not limited to the contents of the specification but must be determined according to the scope of the claims.

Claims

1. A polymer permeable mortar for permeable paving bricks, characterized in that: The components include the following parts by mass: 80-100 parts of silicate cement 40-60 parts of volume-enhancing modified aggregate 2-5 parts modified latex powder 10-20 parts modified basalt fiber 1-2 parts of polycarboxylate superplasticizer 40-50 parts water; The raw materials for preparing the compatibilized modified aggregate include aggregate, acrylamide, and dopamine; the mass ratio of the aggregate, acrylamide, and dopamine is 1:0.2:(0.1-0.15). The raw materials for preparing the modified latex powder include mixed monomers, n-butyl acrylate, and allyltriethoxysilane; the mass ratio of the mixed monomers, n-butyl acrylate, and allyltriethoxysilane is 1:1.5:(0.3-0.4); the mixed monomers include vinyl acetate and styrene; The modified basalt fiber comprises basalt fiber, nano-silicon nitride oxide, and a compatibilizer; the nano-silicon nitride oxide is loaded onto the basalt fiber, and the raw materials for preparing the nano-silicon nitride oxide are vinyltrimethoxysilane and hexamethyldisilazane; the compatibilizer is maleic anhydride.

2. The polymer permeable mortar for permeable paving bricks according to claim 1, characterized in that: The polymer permeable mortar is prepared using the following steps: Silicate cement, compatibilizing modified aggregate, modified latex powder, modified basalt fiber, polycarboxylate superplasticizer and water are mixed and stirred to obtain polymer permeable mortar.

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