Concrete with self-waterproofing function and preparation method thereof

Abstract

The application discloses a self-waterproof concrete and a preparation method thereof. The concrete comprises the following raw materials in parts by weight: 400-500 parts of Portland cement, 550-700 parts of fine aggregate sand, 700-900 parts of coarse aggregate sand, 100-150 parts of fly ash, 20-30 parts of silica ash, 6-12 parts of polycarboxylate superplasticizer, 150-180 parts of water and 6-20 parts of waterproof material. The application realizes a double breakthrough in performance and practicability through reasonable raw material ratio and process. The reasonable collocation of cementitious materials, the optimization of aggregate gradation and the use of water reducing agent lay a foundation for waterproofing while improving the compactness and mechanical properties of the concrete, and the self-waterproof function reduces the later maintenance.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of concrete, in particular to a concrete with self-waterproof function and a preparation method thereof. BACKGROUND

[0002] Concrete is a kind of artificial stone made of cementitious materials, sand and stone as aggregate, water, additives and admixtures, and is widely used in civil engineering. In the field of construction engineering, the waterproof treatment of concrete structure has long relied on external additional waterproof layer, such as waterproofing membrane and waterproof coating. Although these materials can provide waterproof effect in the early stage, they have many drawbacks in practical application. For example, waterproofing membrane needs to be attached to the concrete base layer through hot melting or adhesive, and problems such as hollowing and edge lifting are easy to occur during construction, resulting in waterproof failure; waterproof coating is easy to age and crack under the action of ultraviolet rays, temperature changes and chemical medium erosion, shortening the service life. In addition, once the external waterproof layer is damaged, it is difficult and costly to repair, which is difficult to meet the long-term demand for waterproof durability of underground engineering, hydraulic structure and other structures.

[0003] With the development of building technology, self-waterproof concrete has gradually become a research hotspot, but the existing technology still has shortcomings. Some self-waterproof concretes increase the amount of cement or add expanding agents to improve the density, which can reduce the initial water seepage, but excessive cement will cause high hydration heat and lead to cracking of concrete; if the expanding agent is not properly controlled, it is easy to cause uneven local expansion and form new crack channels. Another type of self-waterproof concrete based on nano materials or polymer modification can improve the waterproof performance, but the dispersion of nano materials is poor, the cost of polymers is high, and the self-repairing ability of cracks is lacking, which cannot cope with the damage caused by load and environmental action in the later stage of concrete.

[0004] In recent years, with the rapid development of large-scale infrastructure construction such as underground comprehensive pipe gallery, super-deep foundation pit and cross-sea tunnel, higher requirements are put forward for the waterproof performance of concrete. Traditional waterproof technology cannot meet the waterproof demand of super-long structure and complex geological conditions, and self-waterproof concrete with self-repairing function has become the development direction of the industry. SUMMARY

[0005] The main purpose of the present application is to provide a concrete with self-waterproof function and a preparation method thereof, which aims to solve the problem that the existing concrete does not have self-waterproof function and will crack and be damaged after long-term use.

[0006] To achieve the above object, the present application provides a self-waterproof concrete, comprising the following raw materials in parts by weight: Portland cement 400-500 parts, fine aggregate sand 550-700 parts, coarse aggregate sand 700-900 parts, fly ash 100-150 parts, silica fume 20-30 parts, polycarboxylate superplasticizer 6-12 parts, water 150-180 parts, and waterproof material 6-20 parts.

[0007] Preferably, the waterproof material comprises epoxy siloxane copolymer liquid and polyurea microcapsules, and the mass ratio of the epoxy siloxane copolymer liquid to the polyurea microcapsules is (3-15):(2-10).

[0008] Preferably, the preparation method of the epoxy siloxane copolymer liquid comprises the following steps:

[0009] S1, dissolving γ-glycidoxypropyltrimethoxysilane and methyltrimethoxysilane in an ethanol-water mixed solution, adding tetrabutyl titanate, and heating under nitrogen protection for a period of time to obtain a mixed solution;

[0010] S2, adding an alkylphenol polyoxyethylene ether aqueous solution dropwise to the mixed solution for emulsification, and performing reduced pressure distillation to obtain an epoxy siloxane copolymer liquid.

[0011] Preferably, in steps S1 and S2, the volume ratio of ethanol to water in the ethanol-water mixed solution is (6-7):(2-4); the mass ratio of the γ-glycidoxypropyltrimethoxysilane, the methyltrimethoxysilane, the tetrabutyl titanate, and the alkylphenol polyoxyethylene ether aqueous solution is (45-55):(25-35):(0.3-0.8):(8-12); and the heating is to 65-75℃, and the reaction is for 3.5-4.5h.

[0012] Preferably, the preparation method of the polyurea microcapsules comprises the following steps:

[0013] S3, dissolving KH550 in an ethanol aqueous solution, adjusting the pH to 4-5, and performing ultrasonic treatment to obtain a dispersion liquid;

[0014] S4, adding the dispersion liquid dropwise to hollow glass microspheres under stirring, and heating for a period of time to obtain modified hollow glass microspheres after the reaction is completed, and then washing and drying;

[0015] S5, dissolving isophorone diisocyanate and polyethylene glycol in acetone, and stirring at 40-50℃ for 2-3h to prepare a polyurea prepolymer solution;

[0016] S6, dispersing the modified hollow glass microspheres in the polyurea prepolymer solution, ultrasonic dispersing, then adding an ethylenediamine aqueous solution dropwise, and reacting under heating to obtain polyurea microcapsules.

[0017] Preferably, in steps S3 and S4, the mass fraction of the aqueous ethanol solution is 45-55%, and the dosages of the KH550, the aqueous ethanol solution and the hollow glass microspheres are (1-2 mL):(5-15 mL):(80-120 g).

[0018] Preferably, in step S4, the stirring speed is 300-500 rpm; the particle size of the hollow glass microspheres is 50-100 μm, and the wall thickness is 8-12 μm; the heating is to 40-50℃, and the reaction is for 1-3 h.

[0019] In step S5, the molar ratio of isophorone diisocyanate to polyethylene glycol is 2:(0.8-1).

[0020] Preferably, in step S6, the mass fraction of the aqueous ethylenediamine solution is 20-30%; the mass ratio of the modified hollow glass microspheres, the polyurea prepolymer solution and the aqueous ethylenediamine solution is (1-2):(3-5):(0.2-0.6), and the heating is to 50-60℃, and the reaction is for 1-2 h.

[0021] Preferably, the preparation method of the waterproof material comprises the following steps:

[0022] The polyurea microcapsules are added into acetone and ultrasonically dispersed for 5-10 min, and then the dispersed polyurea microcapsules are added into the epoxy siloxane copolymer solution under stirring, and the stirring is continued to obtain the waterproof material.

[0023] The application further provides a preparation method of the concrete with the self-waterproof function.

[0024] S10, the raw materials are weighed according to the proportion and prepared for use;

[0025] S20, the portland cement, fine aggregate sand, coarse aggregate sand, fly ash and silica fume are stirred and mixed uniformly to obtain a mixture;

[0026] S30, the polycarboxylate superplasticizer is mixed with water, and then added into the mixture together with the waterproof material, and stirred and coagulated to obtain the concrete with the self-waterproof function.

[0027] Compared with the prior art, the application has the following beneficial effects:

[0028] (1) In the technical scheme provided by the application, the performance and practicability are realized through reasonable raw material ratio and process. The reasonable collocation of cementitious materials, the optimization of aggregate gradation and the use of superplasticizer lay the foundation for waterproofing while improving the compactness and mechanical properties of the concrete, and the self-waterproof function reduces the later maintenance.

[0029] (2) The waterproof material provided by the application adopts epoxy siloxane copolymer liquid and polyurea microcapsules to form a "rigid and flexible" waterproof system. The epoxy siloxane copolymer liquid penetrates into the interior of the concrete and forms a first rigid waterproof barrier through chemical film formation to effectively block capillary pores; the polyurea microcapsules act as "self-healing elastic fillers" to release elastic polyurea fillers to fill gaps in time when the concrete cracks. Both of them play their respective roles and cooperate with each other, the rigid waterproofing inhibits early leakage, the flexible self-repairing responds to later damage, and they jointly provide long-term and reliable waterproof protection for the concrete.

[0030] (3) The application adopts hydrolysis and condensation reaction of γ-glycidyl ether oxypropyl trimethoxysilane and methyl trimethoxysilane under the catalysis of tetrabutyl titanate to form a siloxane network polymer, the polymer reacts with hydroxyl groups in the concrete through chemical bonding to be tightly anchored in the interior of the substrate, fill pores and form a continuous waterproof film, block the water penetration path and reduce the water absorption rate of the concrete; after the hollow glass microbeads are modified by KH550, active groups such as amino groups are introduced on the surface, and the hollow glass microbeads are firmly combined with the polyurea prepolymer through chemical reaction to form core-shell structure microcapsules, when the concrete produces microcracks due to load or environmental effects, the microcapsule shell breaks, and the hollow glass microbeads are released, the hollow glass microbeads as a skeleton component can form a uniformly distributed physical barrier in the material, water will be blocked by these microbeads during the penetration process, the penetration path is prolonged, thereby reducing the water penetration efficiency, at the same time, the polyurea prepolymer reacts with the water or curing agent in the environment to re-form a film at the crack, realizing the "self-repairing" function and improving the waterproof durability. DETAILED DESCRIPTION

[0031] In order to make the purpose, technical scheme and advantages of the embodiments of the application more clear, the technical scheme in the embodiments of the application will be clearly and completely described below. If the specific conditions are not specified in the embodiments, the conventional conditions or the conditions recommended by the manufacturer are adopted. If the manufacturers of the reagents or instruments are not specified, they are all conventional products that can be purchased in the market. In addition, the technical schemes of each embodiment can be combined with each other, but it should be considered that the combination of the technical schemes does not exist and is not within the protection scope of the application when the combination of the technical schemes is contradictory or unachievable. Based on the embodiments in the application, all other embodiments obtained by the ordinary skilled in the art without creative labor are within the protection scope of the application.

[0032] The technical scheme of the application will be further described in detail below in combination with specific embodiments. It should be understood that the following embodiments are only used to explain the application and not used to limit the application.

[0033] Experimental materials:

[0034] Portland cement: ordinary Portland cement with strength grade of 42.5.

[0035] Fly ash: first grade fly ash.

[0036] Fine aggregate sand: particle size of 0.15-4.75 mm.

[0037] Coarse aggregate sand: particle size of 4.75-25 mm.

[0038] Silica fume: purchased from Shijiazhuang Qiantong Mineral Products Co., Ltd., item number 646465486.

[0039] Polycarboxylic acid water reducer: purchased from Zhengzhou Kaidi Chemical Products Co., Ltd., model industrial grade.

[0040] Example 1

[0041] A concrete with self-waterproofing function, comprising the following raw materials in parts by weight: 450 parts of Portland cement, 600 parts of fine aggregate sand, 800 parts of coarse aggregate sand, 120 parts of fly ash, 25 parts of silica fume, 8 parts of polycarboxylic acid water reducer, 160 parts of water, and 15 parts of waterproof material.

[0042] The preparation method of the concrete with self-waterproofing function comprises the following steps:

[0043] S10, weighing each raw material according to the proportion, and reserving;

[0044] S20, stirring and uniformly mixing 450 g of Portland cement, 600 g of fine aggregate sand, 800 g of coarse aggregate sand, 120 g of fly ash, and 25 g of silica fume to obtain a mixture;

[0045] S30, mixing 8 g of polycarboxylic acid water reducer with 160 g of water, and then adding 15 g of waterproof material to the mixture, stirring and setting to obtain a concrete with self-waterproofing function;

[0046] The waterproof material comprises an epoxy siloxane copolymer liquid and polyurea microcapsules, and the mass ratio of the epoxy siloxane copolymer liquid to the polyurea microcapsules is 10:5.

[0047] The preparation method of the waterproof material comprises the following steps:

[0048] 5 g of polyurea microcapsules are added to acetone and ultrasonically dispersed for 8 min, and the dispersed polyurea microcapsules are added to 10 g of epoxy siloxane copolymer liquid under stirring, and continuous stirring is performed to obtain a waterproof material.

[0049] The preparation method of the epoxy siloxane copolymer liquid comprises the following steps:

[0050] S1, 10g of γ-glycidoxypropyltrimethoxysilane and 6g of methyltrimethoxysilane were dissolved in an ethanol-water mixed solution, 0.1g of tetrabutyl titanate was added, heated to 55℃ under nitrogen protection, and reacted for 4h to obtain a mixed solution;

[0051] S2, 2g of an aqueous alkylphenol polyoxyethylene ether solution was added dropwise to the mixed solution for emulsification, and distilled under reduced pressure to obtain an epoxy siloxane copolymer solution;

[0052] The preparation method of the polyurea microcapsule comprises the following steps:

[0053] S3, 0.08mL of KH550 was dissolved in 0.5mL of an ethanol aqueous solution, the pH was adjusted to 4.5, and ultrasonic treatment was performed to obtain a dispersion;

[0054] S4, the dispersion was added dropwise to 5g of hollow glass microspheres under stirring, heated to 45℃, and reacted for 2h, then washed and dried to obtain modified hollow glass microspheres;

[0055] S5, 20g of isophorone diisocyanate and 10g of polyethylene glycol were dissolved in 20mL of acetone, stirred at 45℃ for 2.5h to prepare a polyurea prepolymer solution;

[0056] S6, 5g of modified hollow glass microspheres were dispersed in 20g of the polyurea prepolymer solution, ultrasonic dispersion was performed, then an aqueous ethylenediamine solution was added dropwise, and reacted under heating to obtain polyurea microcapsules.

[0057] Example 2

[0058] A concrete with self-waterproof function comprises the following raw materials in parts by weight: Portland cement 400 parts, fine aggregate sand 550 parts, coarse aggregate sand 700 parts, fly ash 100 parts, silica fume 20 parts, polycarboxylic acid water reducer 6 parts, water 150 parts, and waterproof material 6 parts;

[0059] The preparation method of the concrete with self-waterproof function comprises the following steps:

[0060] S10, the raw materials were weighed according to the proportion and prepared;

[0061] S20, 400g of Portland cement, 550g of fine aggregate sand, 700g of coarse aggregate sand, 100g of fly ash and 20g of silica fume were stirred and mixed uniformly to obtain a mixture;

[0062] S30, 6g of polycarboxylic acid water reducer was mixed with 150g of water, then 6g of waterproof material was added to the mixture, stirred and coagulated to obtain a concrete with self-waterproof function;

[0063] The waterproof material comprises epoxy siloxane copolymer liquid and polyurea microcapsules, and the mass ratio of the epoxy siloxane copolymer liquid and the polyurea microcapsules is 5:1;

[0064] The preparation method of the waterproof material comprises the following steps:

[0065] 1g of polyurea microcapsules is added into acetone and ultrasonically dispersed for 8 min, and the dispersed polyurea microcapsules are added into 5g of epoxy siloxane copolymer liquid under stirring, and stirring is continued to obtain the waterproof material;

[0066] The preparation method of the epoxy siloxane copolymer liquid comprises the following steps:

[0067] S1, 5g of γ-glycidoxypropyltrimethoxysilane and 3g of methyltrimethoxysilane are dissolved in an ethanol-water mixed solution, 0.05g of tetrabutyl titanate is added, and the solution is heated to 50℃ under nitrogen protection, and reacted for 4.5h to obtain a mixed solution;

[0068] S2, 1g of an alkylphenol polyoxyethylene ether aqueous solution is added dropwise to the mixed solution for emulsification, and distilled under reduced pressure to obtain the epoxy siloxane copolymer liquid;

[0069] The preparation method of the polyurea microcapsules comprises the following steps:

[0070] S3, 0.016mL of KH550 is dissolved in 0.1mL of an ethanol aqueous solution, the pH is adjusted to 4.5, and ultrasonic treatment is performed to obtain a dispersion liquid;

[0071] S4, the dispersion liquid is added dropwise to 1g of hollow glass microbeads under stirring, heated to 50℃, and reacted for 1h, and after the reaction is completed, the product is washed and dried to obtain modified hollow glass microbeads;

[0072] S5, 4g of isophorone diisocyanate and 2g of polyethylene glycol are dissolved in 5mL of acetone, and stirred at 45℃ for 2.5h to prepare a polyurea prepolymer solution;

[0073] S6, 1g of the modified hollow glass microbeads is dispersed in 4g of the polyurea prepolymer solution, ultrasonically dispersed, and then an ethylenediamine aqueous solution is added dropwise, and reacted under heating to obtain the polyurea microcapsules.

[0074] Example 3

[0075] A concrete with self-waterproof function comprises the following raw materials in parts by weight: Portland cement 500 parts, fine aggregate sand 700 parts, coarse aggregate sand 900 parts, fly ash 150 parts, silica fume 30 parts, polycarboxylic acid water reducer 12 parts, water 180 parts, and waterproof material 20 parts;

[0076] The preparation method of the concrete with self-waterproof function comprises the following steps:

[0077] S10, each raw material is weighed according to the proportion, and is ready for use;

[0078] S20, 500g of Portland cement, 700g of fine aggregate sand, 900g of coarse aggregate sand, 150g of fly ash and 30g of silica fume are stirred and mixed uniformly to obtain a mixture;

[0079] S30, 12g of polycarboxylic acid water reducer is mixed with 180g of water, and then is added to the mixture together with 20g of waterproof material, and is stirred and coagulated to obtain concrete with self-waterproof function;

[0080] The waterproof material comprises epoxy siloxane copolymer liquid and polyurea microcapsule, and the mass ratio of the epoxy siloxane copolymer liquid to the polyurea microcapsule is 15:5;

[0081] The preparation method of the waterproof material comprises the following steps:

[0082] 5g of polyurea microcapsule is added to acetone, and is ultrasonically dispersed for 8min, and the dispersed polyurea microcapsule is added to 10g of epoxy siloxane copolymer liquid under stirring, and the stirring is continued to obtain the waterproof material;

[0083] The preparation method of the epoxy siloxane copolymer liquid comprises the following steps:

[0084] S1, 15g of γ-glycidyl ether propyltrimethoxysilane and 10g of methyltrimethoxysilane are dissolved in an ethanol-water mixed solution, 0.1g of tetrabutyl titanate is added, and the solution is heated to 55℃ under nitrogen protection, and is reacted for 3.5h to obtain a mixed solution;

[0085] S2, 3g of alkylphenol polyoxyethylene ether aqueous solution is added dropwise to the mixed solution for emulsification, and is distilled under reduced pressure to obtain the epoxy siloxane copolymer liquid;

[0086] The preparation method of the polyurea microcapsule comprises the following steps:

[0087] S3, 0.08mL of KH550 is dissolved in 0.5mL of ethanol aqueous solution, the pH is adjusted to 4.5, and ultrasonic treatment is performed to obtain a dispersion liquid;

[0088] S4, the dispersion liquid is added dropwise to 5g of hollow glass microbeads under stirring, and is heated to 45℃ and reacted for 2h, and after the reaction is completed, the product is washed and dried to obtain modified hollow glass microbeads;

[0089] S5, 20g of isophorone diisocyanate and 10g of polyethylene glycol are dissolved in 20mL of acetone, and are stirred and reacted at 45℃ for 2.5h to prepare a polyurea prepolymer solution;

[0090] S6, dispersing 5 g of modified hollow glass beads in 20 g of polyurea prepolymer solution, ultrasonic dispersion, then adding ethylenediamine aqueous solution dropwise, and reacting under heating to obtain polyurea microcapsules.

[0091] Comparative Example 1

[0092] A kind of concrete, including the following weight parts of raw materials: Portland cement 450 parts, fine aggregate sand 600 parts, coarse aggregate sand 800 parts, fly ash 120 parts, silica ash 25 parts, polycarboxylic acid water reducer 8 parts, water 160 parts, waterproof material 15 parts;

[0093] The preparation method of the concrete comprises the following steps:

[0094] S10, proportionally weighing each raw material, standby;

[0095] S20, stirring and uniformly mixing 450 g of Portland cement, 600 g of fine aggregate sand, 800 g of coarse aggregate sand, 120 g of fly ash and 25 g of silica ash to obtain a mixture;

[0096] S30, mixing 8 g of polycarboxylic acid water reducer with 160 g of water, then adding 15 g of waterproof material to the mixture, stirring and setting to obtain concrete;

[0097] The waterproof material comprises epoxy siloxane copolymer liquid and polyurea microcapsules, and the mass ratio of the epoxy siloxane copolymer liquid to the polyurea microcapsules is 10:5;

[0098] The preparation method of the waterproof material comprises the following steps:

[0099] 5 g of polyurea microcapsules are added to acetone, ultrasonic dispersion is performed for 8 min, and the dispersed polyurea microcapsules are added to 10 g of epoxy siloxane copolymer liquid under stirring, and continuous stirring is performed to obtain a waterproof material;

[0100] The preparation method of the epoxy siloxane copolymer liquid comprises the following steps:

[0101] S1, 10 g of γ-glycidyl ether oxypropyltrimethoxysilane and 6 g of methyltrimethoxysilane are dissolved in an ethanol-water mixed solution, 0.1 g of tetrabutyl titanate is added, heated to 55℃ under nitrogen protection, and reacted for 4 h to obtain a mixed solution;

[0102] The preparation method of the polyurea microcapsules comprises the following steps:

[0103] S3, 0.08 mL of KH550 is dissolved in 0.5 mL of ethanol aqueous solution, the pH is adjusted to 4.5, and ultrasonic treatment is performed to obtain a dispersion liquid;

[0104] S4, drop the dispersion into 5 g hollow glass microspheres under stirring, heat to 45℃, react for 2 h, after the reaction is completed, wash and dry to obtain modified hollow glass microspheres;

[0105] S5, dissolve 20 g isophorone diisocyanate and 10 g polyethylene glycol in 20 mL acetone, stir at 45℃ for 2.5 h to prepare a polyurea prepolymer solution;

[0106] S6, disperse 5 g modified hollow glass microspheres in 20 g polyurea prepolymer solution, ultrasonically disperse, then drop in an aqueous ethylenediamine solution, and react under heating to obtain polyurea microcapsules.

[0107] Comparative Example 1 is compared with Example 1, the mixed solution obtained in step S1 is not treated in step S2.

[0108] Comparative Example 2

[0109] A kind of concrete, including the following weight parts of raw materials: Portland cement 450 parts, fine aggregate sand 600 parts, coarse aggregate sand 800 parts, fly ash 120 parts, silica ash 25 parts, polycarboxylic acid water reducer 8 parts, water 160 parts, waterproof material 15 parts;

[0110] The preparation method of the concrete comprises the following steps:

[0111] S10, weigh each raw material according to the proportion, and stand by;

[0112] S20, mix 450 g Portland cement, 600 g fine aggregate sand, 800 g coarse aggregate sand, 120 g fly ash and 25 g silica ash to obtain a mixture;

[0113] S30, mix 8 g polycarboxylic acid water reducer with 160 g water, then add 15 g waterproof material to the mixture, stir and coagulate to obtain concrete;

[0114] The waterproof material comprises an epoxy siloxane copolymer solution;

[0115] The preparation method of the epoxy siloxane copolymer solution comprises the following steps:

[0116] The preparation method of the epoxy siloxane copolymer solution comprises the following steps:

[0117] S1, dissolve 10 g γ-glycidoxypropyltrimethoxysilane and 6 g methyltrimethoxysilane in an ethanol-water mixed solution, add 0.1 g tetrabutyl titanate, heat to 55℃ under nitrogen protection, and react for 4 h to obtain a mixed solution;

[0118] S2, add 2 g aqueous alkylphenol polyoxyethylene ether solution to the mixed solution for emulsification, and distill under reduced pressure to obtain an epoxy siloxane copolymer solution.

[0119] Comparative Example 2 does not have polyurea microcapsules compared with Example 1.

[0120] Comparative Example 3

[0121] A concrete, comprising the following raw materials in parts by weight: Portland cement 450 parts, fine aggregate sand 600 parts, coarse aggregate sand 800 parts, fly ash 120 parts, silica fume 25 parts, polycarboxylic acid water reducer 8 parts, water 160 parts;

[0122] The preparation method of the concrete comprises the following steps:

[0123] S10, weighing each raw material in proportion, standby;

[0124] S20, 450g of Portland cement, 600g of fine aggregate sand, 800g of coarse aggregate sand, 120g of fly ash and 25g of silica fume are stirred and mixed uniformly to obtain a mixture;

[0125] S30, 8g of polycarboxylic acid water reducer is mixed with 160g of water, then added to the mixture, stirred and coagulated to obtain the concrete.

[0126] Comparative Example 3 does not have a waterproof material compared with Example 1.

[0127] Comparative Example 4

[0128] A concrete, comprising the following raw materials in parts by weight: Portland cement 450 parts, fine aggregate sand 600 parts, coarse aggregate sand 800 parts, fly ash 120 parts, silica fume 25 parts, polycarboxylic acid water reducer 8 parts, water 160 parts, waterproof material 15 parts;

[0129] The preparation method of the concrete comprises the following steps:

[0130] S10, weighing each raw material in proportion, standby;

[0131] S20, 450g of Portland cement, 600g of fine aggregate sand, 800g of coarse aggregate sand, 120g of fly ash and 25g of silica fume are stirred and mixed uniformly to obtain a mixture;

[0132] S30, 8g of polycarboxylic acid water reducer is mixed with 160g of water, then added to the mixture, stirred and coagulated to obtain the concrete.

[0133] The waterproof material comprises epoxy siloxane copolymer liquid and polyurea microcapsules, and the mass ratio of the epoxy siloxane copolymer liquid and the polyurea microcapsules is 10:5;

[0134] The preparation method of the waterproof material comprises the following steps:

[0135] The preparation method of the epoxy siloxane copolymer solution comprises the following steps:

[0136] S1, 10g of γ-glycidyl ether propyltrimethoxysilane and 6g of methyltrimethoxysilane were dissolved in an ethanol-water mixed solution, 0.1g of tetrabutyl titanate was added, heated to 55℃ under nitrogen protection, and reacted for 4h to obtain a mixed solution;

[0137] S2, 2g of alkylphenol polyoxyethylene ether aqueous solution was added dropwise to the mixed solution for emulsification, and vacuum distillation was performed to obtain an epoxy siloxane copolymer solution;

[0138] The preparation method of the polyurea microcapsule comprises the following steps:

[0139] S5, 20g of isophorone diisocyanate and 10g of polyethylene glycol were dissolved in 20mL of acetone, and stirred at 45℃ for 2.5h to prepare a polyurea prepolymer solution;

[0140] S6, 5g of hollow glass microbeads were dispersed in 20g of the polyurea prepolymer solution, ultrasonically dispersed, then 2-ethylenediamine aqueous solution was added dropwise, and reacted under heating to obtain polyurea microcapsules.

[0141] Comparative Example 4 and Example 1, the hollow glass microbeads were not modified.

[0142] Comparative Example 5

[0143] A kind of concrete, including the following weight parts of raw materials: Portland cement 450 parts, fine aggregate sand 600 parts, coarse aggregate sand 800 parts, fly ash 120 parts, silica ash 25 parts, polycarboxylic acid water reducer 8 parts, water 160 parts, waterproof material 15 parts;

[0144] The preparation method of the concrete comprises the following steps:

[0145] S10, the raw materials were weighed according to the proportion and prepared;

[0146] S20, 450g of Portland cement, 600g of fine aggregate sand, 800g of coarse aggregate sand, 120g of fly ash and 25g of silica ash were stirred and mixed uniformly to obtain a mixture;

[0147] S30, 8g of polycarboxylic acid water reducer was mixed with 160g of water, then 15g of waterproof material was added to the mixture, and stirred and coagulated to obtain concrete;

[0148] The waterproof material comprises an epoxy siloxane copolymer solution and modified hollow glass microbeads, and the mass ratio of the epoxy siloxane copolymer solution and the modified hollow glass microbeads is 10:5;

[0149] The preparation method of the waterproof material comprises the following steps:

[0150] 5g modified hollow glass beads are added into acetone, and ultrasonic dispersion is carried out for 8 min, and the dispersed modified hollow glass beads are added into 10g epoxy siloxane copolymer solution under stirring, and stirring is continued to obtain a waterproof material;

[0151] The preparation method of the epoxy siloxane copolymer solution comprises the following steps:

[0152] S1, 10g of γ-glycidoxypropyltrimethoxysilane and 6g of methyltrimethoxysilane are dissolved in an ethanol-water mixed solution, 0.1g of tetrabutyl titanate is added, and the solution is heated to 55℃ under nitrogen protection, and reacted for 4h to obtain a mixed solution;

[0153] S2, 2g of an alkylphenol polyoxyethylene ether aqueous solution is added dropwise to the mixed solution for emulsification, and vacuum distillation is carried out to obtain an epoxy siloxane copolymer solution;

[0154] The preparation method of the polyurea microcapsule comprises the following steps:

[0155] S3, 0.08mL of KH550 is dissolved in 0.5mL of an ethanol aqueous solution, the pH is adjusted to 4.5, and ultrasonic treatment is carried out to obtain a dispersion liquid;

[0156] S4, the dispersion liquid is added dropwise to 5g of hollow glass beads under stirring, and heated to 45℃ and reacted for 2h, and after the reaction is completed, washing and drying are carried out to obtain modified hollow glass beads.

[0157] Comparative Example 5 and Example 1, the modified hollow glass beads are not treated with a polyurea prepolymer solution.

[0158] Test method and results

[0159] The concrete prepared in Examples 1-3 and Comparative Examples 1-5 is cured for 28 days, and then subjected to maximum impermeable pressure test and compressive strength test. When testing the maximum impermeable pressure, the standard test piece with a curing age of 28 days is used as the object, and when the test is carried out according to the standard test method, the maximum water pressure at which 5 out of 6 test pieces in each group do not appear to be permeated is used to represent. The test results are shown in Table 1.

[0160]

[0161] From the results in Table 1 above, it can be seen that the concrete prepared in Examples 1-3 of the present application has better waterproof effect compared to the concrete prepared in Comparative Examples 1-5.

[0162] The above merely describes the preferred embodiments of the present application, and is not intended to limit the patent scope of the present application. The present application can have various modifications and changes for those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the patent protection scope of the present application.

Claims

1. A type of concrete with self-waterproofing function, characterized in that, The raw materials include silicate cement 400-500 parts, fine aggregate sand 550-700 parts, coarse aggregate sand 700-900 parts, fly ash 100-150 parts, silica fume 20-30 parts, polycarboxylic acid water reducing agent 6-12 parts, water 150-180 parts, and waterproof material 6-20 parts; The waterproof material comprises epoxy siloxane copolymer liquid and polyurea microcapsules, and the mass ratio of the epoxy siloxane copolymer liquid to the polyurea microcapsules is (3-15):(2-10); The preparation method of the epoxy siloxane copolymer liquid comprises the following steps: S1, γ-glycidoxypropyltrimethoxysilane and methyltrimethoxysilane are dissolved in an ethanol-water mixed solution, tetrabutyl titanate is added, and the mixture is heated for a period of time under nitrogen protection to obtain a mixed solution; S2, alkylphenol polyoxyethylene ether aqueous solution is added dropwise to the mixed solution for emulsification, and vacuum distillation is performed to obtain the epoxy siloxane copolymer liquid; The preparation method of the polyurea microcapsules comprises the following steps: S3, KH550 is dissolved in an ethanol aqueous solution, the pH is adjusted to 4-5, and ultrasonic treatment is performed to obtain a dispersion liquid; S4, the dispersion liquid is added dropwise to hollow glass microspheres under stirring, and heated for a period of time to obtain modified hollow glass microspheres after washing and drying; S5, isophorone diisocyanate and polyethylene glycol are dissolved in acetone, and stirred for 2-3 h at 40-50℃ to obtain a polyurea prepolymer solution; S6, the modified hollow glass microspheres are dispersed in the polyurea prepolymer solution, ultrasonic dispersion is performed, then ethylenediamine aqueous solution is added dropwise, and heated for reaction to obtain polyurea microcapsules.

2. The concrete having a self-waterproofing function according to claim 1, characterized by, In steps S1 and S2, the volume ratio of ethanol to water in the ethanol-water mixed solution is (6-7):(2-4); the mass ratio of γ-glycidoxypropyltrimethoxysilane, methyltrimethoxysilane, tetrabutyl titanate and alkylphenol polyoxyethylene ether aqueous solution is (45-55):(25-35):(0.3-0.8):(8-12); the heating is to 50-60℃, and the reaction is for 3.5-4.5 h.

3. The concrete having a self-waterproofing function according to claim 1, characterized by, In steps S3 and S4, the mass fraction of the ethanol aqueous solution is 45-55%, and the dosage ratio of KH550, ethanol aqueous solution and hollow glass microspheres is (1-2 mL):(5-15 mL):(80-120 g).

4. The self-waterproofing concrete according to claim 1, wherein In step S4, the stirring speed is 300-500 rpm; the particle size of the hollow glass microspheres is 50-100 μm, and the wall thickness is 8-12 μm; the heating is to 40-50℃, and the reaction is for 1-3 h; In step S5, the molar ratio of isophorone diisocyanate to polyethylene glycol is 2:(0.8-1).

5. The self-waterproofing concrete according to claim 1, wherein In step S6, the mass fraction of the ethylenediamine aqueous solution is 20%-30%; the mass ratio of the modified hollow glass microspheres, polyurea prepolymer solution and ethylenediamine aqueous solution is (1-2):(3-5):(0.2-0.6), and the heating is to 50-60℃, and the reaction is for 1-2 h.

6. The self-waterproofing concrete according to claim 1, wherein The preparation method of the waterproof material comprises the following steps: The polyurea microcapsules are added into acetone, ultrasonically dispersed for 5-10 minutes, and then the dispersed polyurea microcapsules are added into the epoxy siloxane copolymer solution under stirring to obtain the waterproof material.

7. A method for producing the concrete having a self-waterproofing function according to any one of claims 1 to 6, characterized by, The method comprises the following steps: S10, proportionally weighing each raw material and reserving; S20, stirring and mixing silicate cement, fine aggregate sand, coarse aggregate sand, fly ash and silica fume to obtain a mixture; S30, mixing polycarboxylic acid water reducer with water, and then adding the mixture and the waterproof material into the mixture to stir and coagulate, so as to obtain the concrete with self-waterproof function.

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