Cement-based pervious paving strength restorer and method of use

Abstract

The application discloses a cement-based water-permeable pavement strength recovery agent and a use method thereof. The strength recovery maintenance agent comprises components A, B and C, wherein the component A comprises the following raw materials in percentage by weight: calcium salt 15-25%, fluorine-containing surfactant 3-5% and the balance of water; the component B comprises the following raw materials in percentage by weight: water-soluble modified chitosan 18-22%, water glass 20-35%, sodium fluorosilicate 5-10% and the balance of water; and the component C comprises the following raw materials in percentage by weight: calcium salt 35-45%, fluorine-containing surfactant 3-5%, thickening agent 12-25% and the balance of water. The strength recovery agent is sprayed to the cement-based water-permeable pavement in sequence in the form of A, B and C. The strength recovery maintenance agent can effectively recover and improve the strength of damaged cement-based water-permeable pavement materials and improve the overall service life of the water-permeable pavement.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of water-permeable pavement, and particularly relates to a cement-based water-permeable pavement strength restorer and a use method thereof. BACKGROUND

[0002] The pavement paved with water-permeable materials has multiple advantages, such as improving water circulation in the environment, purifying pavement rainwater, reducing urban "heat island effect", absorbing urban noise, etc. However, due to its porous structure, its strength is far inferior to that of dense concrete structure. In addition, the durability of the water-permeable pavement, especially the anti-freeze-thaw cycle capability, is naturally poor. At present, researches and patents are concentrated in aspects of improving aggregate bonding strength, optimizing mix proportion, etc. to improve the overall initial strength and durability. However, these methods have limitations, especially for the water-permeable pavement in the northern cold region, due to the continuous freeze-thaw cycle, the strength decays quickly, which leads to a serious shortening of the service life of the water-permeable pavement. Remodeling and reconstruction will waste cement-based material resources, therefore, researching the strength restorer of the cement-based water-permeable pavement material to prolong its service life is an effective way to realize energy saving and emission reduction, resource saving and environmental protection in the low-carbon economic era in the field of water-permeable materials. SUMMARY

[0003] The application aims to provide a cement-based water-permeable pavement material strength restorer and a use method thereof, which can effectively restore and improve the strength of damaged cement-based water-permeable pavement material and improve the overall service life of the water-permeable pavement.

[0004] In order to solve the above technical problems, the application adopts the following technical solutions:

[0005] The application provides a cement-based water-permeable pavement material strength restorer, which comprises component A, component B and component C, wherein:

[0006] Component A comprises the following raw materials in percentage by weight: calcium salt 15-25%, fluorine-containing surfactant 3-5% and the balance of water;

[0007] Component B comprises the following raw materials in percentage by weight: water-soluble modified chitosan 18-22%, water glass 20-35%, sodium fluorosilicate 5-10% and the balance of water;

[0008] Component C comprises the following raw materials in percentage by weight: calcium salt 35-45%, fluorine-containing surfactant 3-5%, thickening agent 12-25% and the balance of water.

[0009] The cement-based water-permeable pavement material strength restorer of the present application comprises component A, component B and component C; wherein, in component A, calcium salt and fluorine-containing surfactant are compounded, calcium ions can penetrate into the concrete surface layer and the deep part of concrete crack defects, then react with modified chitosan in component B to generate complex network structure to wrap and fix the hard product generated after the replacement reaction of water glass and calcium ions, the product has good plugging and filling effect on the inside of concrete cracks and narrow connecting parts; finally, the unreacted water glass will react with the supplemented calcium ions in component C to reinforce the surface exposed to the air. At the same time, the fluorine-containing surfactant in component A can effectively reduce the surface tension, improve the wettability of liquid on the solid surface and reduce the friction between the solid surfaces, so that the already wetted water-permeable brick structure no longer blocks the subsequent components, which is more conducive to the deep penetration of the components into the bottom of the water-permeable brick, avoiding the phenomenon that only the surface reacts. Sodium fluorosilicate in component B can be used as an additive for the reaction of calcium and water glass, and can also delay corrosion and oxidation, avoiding the influence of the outside during the reaction. The strength recovery curing agent can effectively recover and improve the strength of the damaged cement-based water-permeable pavement material, and improve the overall service life of the water-permeable pavement.

[0010] According to the above scheme, the calcium salt refers to a salt formed by the combination of calcium ions and acid radicals; preferably, the calcium salt is one or more of calcium chloride, calcium chlorate and calcium hypochlorite.

[0011] According to the above scheme, the fluorine-containing surfactant is an amphoteric fluorine-containing surfactant; preferably, it is one or more of ammonium perfluoroalkyl propyl sulfonate (FAS), sodium perfluoroalkyl propyl sulfonate (PFOSA), sodium perfluorodocosyl alkyl sulfonate (SIA) and perfluorododecyl betaine (FTAB).

[0012] According to the above scheme, the water glass comprises at least one of sodium water glass and potassium water glass, and the molecular formula is Na2O·nSiO2 and K2O·nSiO2, respectively. The coefficient n in the formula is called the modulus of water glass. In order to better dissolve in normal temperature water solution, n is preferably 1.

[0013] According to the above scheme, the water-soluble modified chitosan is 2-amino-β(1,4) glucan.

[0014] According to the above scheme, the thickening agent is water-absorbing resin.

[0015] According to the above scheme, the strength restorer is sprayed in the order of A, B and C to the cement-based water-permeable pavement in a continuous and uniform manner.

[0016] Preferably, when the flow rate of component A is Q, the amount of component B is 450·Q, and the unit is L; the amount of component C is 270·Q, and the unit is L; wherein Q=39.5d / φ 1.5+0.03, Q is the spraying flow, L / m 2 • s; d is the height of the water permeable layer, m; φ is the porosity of the water permeable pavement layer, %.

[0017] More preferably, the C component is diluted at a dilution rate Z, where Z = 1 / [0.3 * (φ / 7.9) 0.5 + 7.6R + 0.1], where Z is the water dilution rate; R is the average pore radius, m; φ is the porosity of the water permeable pavement layer, %. Where Z = mass after dilution / mass before dilution.

[0018] Preferably, after the A spraying is completed, the surface is covered with a film and left to stand for 4-6h; after the B spraying is completed, left to stand for 20-24h; after the C spraying is completed, left to stand for 20-24h.

[0019] A method for using the above-mentioned strength restorer for cement-based water permeable pavement material is provided, comprising the following steps:

[0020] 1) Cleaning the cement-based water permeable pavement;

[0021] 2) Spraying component A onto the cement-based water permeable pavement in a continuous and uniform manner, with a fixed time of 4-6min, and a spraying flow Q = 39.5d / φ 1.5 + 0.03

[0022] Where: Q is the spraying flow, L / m 2 • s; d is the height of the water permeable layer, m; φ is the porosity of the water permeable pavement layer, %.

[0023] After the spraying of component A is completed, the surface is covered with a film and left to stand for 4-8h;

[0024] 3) After component A has fully penetrated into the water permeable material, remove the film and spray component B evenly onto the water permeable pavement, with the amount of component B determined according to the amount of component A, as follows: V = 450 * Q

[0025] Where: V is the amount of component B, L;

[0026] After the spraying of component B is completed, it needs to be left to stand for 20-24h, in order to make the reaction more complete and the reaction product fully fixed in the weak areas, during which time vibration and water scouring should be avoided;

[0027] 4) Before spraying component C, first determine its amount, as follows: M = 270 * Q, where M is the amount of component C, L. In order to ensure that component C has sufficient time to stay in the pores of the water permeable pavement, the water dilution rate of component C needs to be determined according to the porosity and average pore size, in order to change the viscosity and fluidity of component C. The empirical formula is as follows: Z = 1 / (0.3 * (φ / 7.9) 0.5 + 7.6R + 0.1)

[0028] wherein: Z is the water dilution rate; R is the average pore radius, m;

[0029] After the spraying is completed, the surface is allowed to stand for 20-24 hours.

[0030] According to the above scheme, in the step 1), the cleaning is to flush the surface with a low-pressure water flow and clean the surface impurities.

[0031] The beneficial effects of the present application are as follows:

[0032] 1. The present application provides a cement-based permeable pavement strength restorer, which adopts a multi-component reactant step-by-step addition method to complete the "penetration-distribution-reaction-fixation-wrapping-reinforcement" of the reactants. First, the calcium ions in component A penetrate into the cement-based permeable pavement and are uniformly distributed. Second, the complex network structure formed by the modified chitosan and calcium ions in component B fixes the hard product calcium silicate generated by the water glass and calcium ions, and forms wrapping and filling at the defect cracks and narrow bonding between aggregates. Finally, component C continues to provide calcium ions to form a hard shell on the surface of the accumulation, reinforcing the structure. Components A, B and C cooperate to achieve the first non-destructive repair of the strength of the cement-based permeable pavement, and have a wide application prospect.

[0033] 2. The present application provides a use method of a cement-based permeable pavement strength restorer. First, according to the experience formula established according to the height and porosity of the permeable layer, the spraying flow of component A is adjusted to ensure the uniformity of the distribution of calcium ions, and the amount of component B is determined according to component A to make the reaction more complete. Second, component C is diluted according to the porosity and average pore size to control the viscosity value and prolong the residence time of the through-hole of the permeable pavement material, so that the reaction is more complete. DETAILED DESCRIPTION

[0034] In order to make the purpose, technical scheme and advantages of the present application clearer and more apparent, the present application will be further described in detail below with reference to examples. It should be understood that the specific examples described herein are only used to explain the present application and not to limit the present application.

[0035] A cement-based permeable pavement material strength restorer is provided in the embodiments of the present application. The strength restorer comprises component A, component B and component C, wherein:

[0036] Component A comprises calcium salt 15-25%, fluorine-containing surfactant 3-5% and the balance of water by weight percentage;

[0037] Component B comprises water-soluble modified chitosan 18%-22%, water glass 20%-35%, fluorosilicate 5%-10% and the balance of water by weight percentage;

[0038] Component C comprises the following weight percentages of calcium salt 35-45%, fluorine-containing surfactant 3-5%, thickening agent 12-25%, and the balance water; wherein:

[0039] The calcium salt is calcium chloride;

[0040] The fluorine-containing surfactant is sodium perfluorooctanesulfonyl propyl sulfonate (PFOSA);

[0041] The water glass is sodium silicate;

[0042] The water-soluble modified chitosan is 2-amino-β(1,4) glucan;

[0043] The thickening agent is Shandong Nol water-absorbing resin NR-610S.

[0044] The use method of the cement-based water-permeable pavement material strength restorer in the embodiment of the application comprises the following steps:

[0045] 1) Before spraying the strength restorer of the application, the water-permeable pavement surface is cleaned. The cleaning process uses low-pressure water flow to flush the surface and remove surface impurities.

[0046] 2) The A component is continuously and uniformly sprayed onto the cement-based water-permeable pavement in a spraying manner. The spraying time is fixed at 5 minutes, and the spraying flow rate is Q. The spraying flow rate should be controllable. According to different water-permeable pavement porosities, different spraying flow rates are matched, and a large number of tests are carried out to obtain the empirical formula as follows: Q = 39.5d / φ 1.5 + 0.03

[0047] Wherein: Q is the spraying flow rate, L / m 2 ·s; d is the height of the water-permeable layer, m; φ is the porosity of the water-permeable pavement layer, %.

[0048] 3) After the A component is sprayed, the surface is covered and left for 4 hours to allow the A component to fully penetrate into the water-permeable material. Then the covering is removed, and the B component is uniformly sprayed onto the water-permeable pavement. The amount of the B component is determined according to the amount of the A component, and the formula is as follows: V = 450·Q

[0049] Wherein: V is the amount of the B component, L.

[0050] 4) After the B component is sprayed, it needs to be left for 24 hours for curing. In order to make the reaction more complete and the reaction product be fully fixed in the weak area, vibration and water flushing should be avoided during this period.

[0051] 5) Confirm the amount of C component is M, and dilute according to Z, spray the C component to the permeable pavement, and after the spraying, maintain for 20 hours; wherein: the amount of C component is calculated as follows: M=270·Q, wherein M is the amount of C component, L. In order to ensure that the C component has sufficient time to stay in the pores of the permeable pavement, the water dilution rate of the C component needs to be determined according to the porosity and the average pore size to change the viscosity and fluidity of the C component. The empirical formula is as follows:

[0052] Z=1 / [0.3·(φ / 7.9) 0.5 +7.6R+0.1]

[0053] wherein Z is the water dilution rate; φ is the porosity of the permeable pavement layer, %; R is the average pore radius, m.

[0054] The concrete surface enhancer and the use method thereof provided by the present application will be described in detail below in combination with specific examples, but they should not be understood as limiting the protection scope of the present application.

[0055] Examples 1-5

[0056] A cement-based permeable pavement strength recovery agent is provided, wherein the component ratio is shown in Table 1:

[0057] Table 1. Component ratio table of the cement-based permeable pavement strength recovery agent described in Examples 1-5

[0058]

[0059] Table 2. Component table of the cement-based permeable pavement described in Examples 1-5

[0060]

[0061] After maintenance according to the ratio and components of Examples 1-5, the strength and wear resistance of the cement-based permeable pavement material are tested according to the standard of GB / T 25993-2010, and the test results are shown in Table 3:

[0062] Table 3. Strength recovery of the cement-based permeable pavement before and after maintenance described in Examples 1-5

[0063]

[0064] The technical solutions and beneficial effects of the present application are described in detail in the above examples, and it should be understood that the above description is only a specific embodiment of the present application and is not used to limit the present application. Any modification, supplement and equivalent replacement made within the principle range of the present application shall be included in the protection scope of the present application.

Claims

1. A strength restorer for cement-based permeable pavement materials, characterized in that, The strength-restoring maintenance agent comprises component A, component B, and component C, wherein: Component A contains the following raw materials by weight percentage: 15-25% calcium salt, 3-5% fluorinated surfactant, and the balance water; Component B contains the following raw materials by weight percentage: 18-22% water-soluble modified chitosan, 20-35% water glass, 5-10% sodium fluorosilicate, and the balance being water; Component C comprises the following raw materials by weight percentage: 35-45% calcium salt, 3-5% fluorinated surfactant, 12-25% thickener, and the balance water; wherein: The fluorinated surfactant is one or more of perfluorooctyl propanesulfonate ammonium, perfluorooctyl propanesulfonate sodium, 24-carbon perfluoroalkyl hydroxyethyl sulfonate sodium, and perfluorododecyl betaine. The water-soluble modified chitosan is 2-amino-β(1,4)glucan.

2. The strength restorer for cement-based permeable pavement materials according to claim 1, characterized in that, The calcium salt is one or more of calcium chloride, calcium chlorate, and calcium hypochlorite; the water glass includes at least one of sodium water glass and potassium water glass.

3. The strength restorer for cement-based permeable pavement materials according to claim 1, characterized in that, The thickener is a water-absorbing resin.

4. The strength restorer for cement-based permeable pavement materials according to claim 1, characterized in that, The strength restoring agent is applied continuously and evenly to the cement-based permeable pavement in the order of components A, B, and C by spraying.

5. The strength restorer for cement-based permeable pavement materials according to claim 4, characterized in that, When the flow rate of component A is Q, the dosage of component B is 450·Q (in L); the dosage of component C is 270·Q (in L); where Q = 39.5d / φ 1.5 +0.03, Q is the spray flow rate, L / m 2 ·s; d is the height of the permeable layer, m; φ is the porosity of the permeable pavement, %.

6. The strength restorer for cement-based permeable pavement materials according to claim 4, characterized in that, Component C is diluted according to a dilution rate Z, where Z = 1 / [0.3·(φ / 7.9)]. 0.5 +7.6R+0.1], where Z is the water dilution rate; R is the average pore radius, m; φ is the porosity of the permeable pavement, %.

7. The strength restorer for cement-based permeable pavement materials according to claim 4, characterized in that, A. After spraying, cover the surface with a film and let it stand for 4-6 hours; B. After spraying, let it stand for 20-24 hours; C. After spraying, let it stand for 20-24 hours.

8. A method of using the strength restoring agent for cement-based permeable pavement materials as described in any one of claims 1-7, characterized in that, Includes the following steps: 1) Clean the cement-based permeable pavement; 2) Component A is continuously and evenly applied to the cement-based permeable pavement using a spraying method. The application time is fixed at 4-6 minutes, and the spraying flow rate is Q=39.5d / φ. 1.5 +0.03 Where: Q is the spray flow rate, L / m 2 ·s; d is the height of the permeable layer, m; φ is the porosity of the permeable pavement, % After spraying, cover the surface with a film and let it stand for 4-8 hours; 3) Apply component B evenly to the permeable pavement. The amount of component B is determined based on the amount of component A, using the formula: V = 450·Q Where: V is the amount of component B used, in L; After component B has been sprayed, allow it to stand for 20-24 hours for curing. 4) Finally, spray component C. The formula for the dosage of component C is: M = 270·Q, where M is the dosage of component C in L; at the same time, component C is diluted according to the water dilution rate Z, Z = 1 / [0.3·(φ / 7.9)]. 0.5 +7.6R+0.1] Where: Z is the water dilution rate; R is the average pore radius, in meters; After spraying, let it stand for 20-24 hours.

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