Anti-permeability concrete containing polycarboxylic acid early-strength water reducing agent and preparation method of anti-permeability concrete

Abstract

The invention relates to the technical field of concrete materials, and particularly discloses impervious concrete containing a polycarboxylic acid early-strength water reducing agent and a preparation method of the impervious concrete. The impervious concrete containing the polycarboxylic acid early-strength water reducing agent comprises the following components in parts by mass: 100 parts of water; 310 to 320 parts of cement; 33 to 37 parts of fly ash; 300 to 310 parts of fine aggregate; 670 to 680 parts of coarse aggregate; 210 to 220 parts of modified desert sand; 5.7-6.1 parts of a polycarboxylic acid early strength water reducing agent; the modified desert sand is prepared by modifying desert sand through a modifier; the modified liquid is a compound of water, stearamide propyl dimethyl tertiary amine, dodecyl trimethyl ammonium bromide and benzalkonium bromide. The concrete anti-seepage agent has the advantage of improving the anti-seepage performance of concrete.

Description

Technical Field

[0001] The invention relates to the field of concrete materials, in particular to an anti-seepage concrete containing a polycarboxylic acid early strength water reducing agent and a preparation method thereof. Background Art

[0002] Concrete is a composite material composed of aggregates bonded together by cementitious materials. Concrete usually uses cement as a cementitious material. Hydration reaction will occur when cement comes into contact with water, thereby solidifying the concrete. This allows the concrete to be formed into various shapes, which determines whether the concrete is suitable as a building material.

[0003] Aggregates of concrete are mainly sand and stone, and the gaps between the sand and stone are filled with cement slurry to bond the sand and stone to form a solidified whole. Ordinary cement slurry has poor fluidity, and it is necessary to increase the amount of water to improve the fluidity of cement slurry, resulting in the evaporation of excess water in the concrete during the solidification process, so that a large number of micropores will appear in the solidified concrete, resulting in the general impermeability of ordinary concrete. In the prior art, polycarboxylic acid early strength water-reducing agent is mainly added to reduce the amount of water and improve the fluidity of cement slurry. The addition of polycarboxylic acid early strength water-reducing agent can improve the impermeability of concrete to a certain extent. However, due to the large number of aggregate gaps inside the concrete, it is difficult for cement slurry to fully fill the gaps, resulting in limited improvement in the impermeability of concrete.

[0004] In order to further improve the impermeability of concrete, powder fillers with smaller particle sizes are usually added in order to fill the gaps in the concrete. However, the addition of a large amount of powder will increase the viscosity of the cement slurry, making it more difficult for the cement slurry to penetrate into the gaps between aggregates, which will in turn cause a significant decrease in the strength of the concrete and worse impermeability. Therefore, only a small amount of powder filler can be added. The addition of a small amount of powder filler makes it difficult to completely fill the gaps between aggregates, resulting in the effect of improving the impermeability performance being difficult to achieve as expected. Therefore, there is still room for improvement. Summary of the invention

[0005] In order to improve the anti-seepage performance of concrete, the present application provides an anti-seepage concrete containing a polycarboxylic acid early strength water reducing agent and a preparation method thereof.

[0006] In the first aspect, the present application provides an anti-seepage concrete containing a polycarboxylic acid early strength water reducing agent, using the following technical solution: An impermeable concrete containing a polycarboxylate early strength water reducing agent comprises the following components in parts by weight: 100 parts water; 310-320 parts of cement; Fly ash 33-37 parts; 300-310 parts of fine aggregate; 670-680 parts of coarse aggregate; 210-220 parts of modified desert sand; 5.7-6.1 parts of polycarboxylic acid early strength water reducing agent; The modified desert sand is prepared by modifying desert sand with a modifier; The modified liquid is a compound of water, stearamidopropyl dimethyl tertiary amine, dodecyl trimethyl ammonium bromide and benzalkonium bromide.

[0007] By adopting the above technical scheme, the surface activity of the desert sand can be changed by modifying the desert sand with a modifying liquid prepared by mixing stearamidopropyl dimethyl tertiary amine, dodecyltrimethylammonium bromide and benzalkonium bromide, so that the viscosity of the cement slurry will not be increased after a large amount of desert sand is used as a powder filler, so that the cement slurry can obtain better fluidity under the action of the polycarboxylic acid early strength water reducing agent, and at the same time, the density of the concrete is significantly improved by filling the gap between aggregates with the desert sand, thereby significantly improving the strength and impermeability of the concrete.

[0008] Moreover, the large amount of desert sand added can reduce the amount of sand and stone used, and make full use of desert resources to better achieve green environmental protection.

[0009] Preferably, the mass ratio of stearamidopropyl dimethyl tertiary amine, dodecyltrimethylammonium bromide and benzalkonium bromide is 9-11:16-18:4-6.

[0010] By adopting the above technical scheme and specifically selecting the mass ratio of stearamidopropyl dimethyl tertiary amine, dodecyltrimethylammonium bromide and benzalkonium bromide, the modification effect of the modification liquid on desert sand is better, and the strength and impermeability of the concrete after curing are better.

[0011] Preferably, the mass ratio of the water, stearamidopropyl dimethyl tertiary amine, dodecyltrimethylammonium bromide and benzalkonium bromide is 300:9-11:16-18:4-6.

[0012] By adopting the above technical scheme and specifically selecting the mass ratio of water, stearamidopropyl dimethyl tertiary amine, dodecyltrimethylammonium bromide and benzalkonium bromide, the modified liquid has a good modification effect on desert sand, and can effectively control costs and has higher economic value.

[0013] Preferably, the particle size of the desert sand is 0.1-0.2 mm.

[0014] By adopting the above technical solution and specifically selecting the particle size of desert sand to be 0.1-0.2 mm, the modified desert sand can better fill the gaps in concrete, better improve the density of concrete, and make the concrete stronger and more impermeable.

[0015] Preferably, the method for preparing the modified desert sand comprises the following steps: Step 1), mixing water, stearamidopropyl dimethyl tertiary amine, dodecyl trimethyl ammonium bromide and benzalkonium bromide to obtain a modified solution; Step 2), adding desert sand into the modified liquid, stirring for 90-120 minutes, filtering and drying to obtain modified desert sand.

[0016] By adopting the above technical solution, the modification effect of desert sand is better, and the modified desert sand can be added in large quantities to significantly improve the strength and impermeability of concrete.

[0017] Preferably, in step 2), after adding the desert sand into the modified liquid, it is first heated to 50-60° C. and then stirred for 90-120 minutes.

[0018] By adopting the above technical solution and carrying out the modification at 50-60°C, the modification effect is better, the density of the prepared concrete is higher, and the strength and impermeability are better.

[0019] Preferably, in step 2), the mass ratio of desert sand to modifying liquid is 1:2-3.

[0020] By adopting the above technical solution and specifically selecting the mass ratio of desert sand to modifying liquid, the modification effect can be ensured while the consumption of modifying liquid can be well controlled, thus reducing resource waste and having high economic value.

[0021] In a second aspect, the present application provides a method for preparing an impermeable concrete containing a polycarboxylic acid early strength water reducing agent, using the following technical solution: A method for preparing the above-mentioned impermeable concrete containing polycarboxylic acid early strength water reducing agent comprises the following steps: Step 01), cement, fly ash, fine aggregate, coarse aggregate, modified desert sand, and polycarboxylic acid early strength water reducing agent are uniformly mixed to obtain a premix; Step 02), adding water to the premix and stirring evenly to obtain a concrete mixture; Step 03), injecting the concrete mixture into the mold, curing, and demoulding to obtain the impermeable concrete containing the polycarboxylic acid early strength water reducing agent.

[0022] By adopting the above technical scheme, the obtained anti-seepage concrete with polycarboxylic acid early strength water reducing agent has higher density, higher strength and anti-seepage performance of the concrete, can be well applied to projects with higher requirements for anti-seepage performance, and has higher economic value and application prospects.

[0023] In summary, this application has the following beneficial effects: 1. Since the present application modifies desert sand with a modifying liquid compounded with stearamidopropyl dimethyl tertiary amine, dodecyl trimethyl ammonium bromide and benzalkonium bromide, the surface activity of desert sand can be changed, so that after a large amount of desert sand is used as a powder filler, the viscosity of the cement slurry will not be increased, so that the cement slurry can obtain better fluidity under the action of the polycarboxylic acid early strength water reducing agent, and at the same time, the density of the concrete is significantly improved by filling the gap between aggregates with desert sand, thereby significantly improving the strength and impermeability of the concrete.

[0024] 2. In the present application, it is preferred to specifically select the mass ratio of stearamidopropyl dimethyl tertiary amine, dodecyltrimethylammonium bromide and benzalkonium bromide so that the modification effect of the modified liquid on desert sand is better, and the strength and impermeability of the concrete after curing are better.

[0025] 3. In the present application, it is preferred to specifically select the mass ratio of water, stearamidopropyl dimethyl tertiary amine, dodecyltrimethylammonium bromide and benzalkonium bromide so that the modified liquid has a good modification effect on desert sand, while effectively controlling costs and having higher economic value. DETAILED DESCRIPTION

[0026] The present application is further described in detail below with reference to the embodiments.

[0027] Example 1 An impermeable concrete containing a polycarboxylate early strength water reducing agent comprises the following components in parts by weight: Water, cement, fly ash, fine aggregate, coarse aggregate, modified desert sand, polycarboxylic acid early strength water reducing agent.

[0028] The cement is ordinary Portland cement, Jidong cement, specification, P.O42.5.

[0029] The fly ash is sourced from commercially available, first-grade fly ash.

[0030] Fine aggregate comes from commercially available natural river sand with a particle size of 3-5 mm.

[0031] The coarse aggregate was obtained from commercially available basalt crushed stone with a particle size of 15-20 mm.

[0032] Polycarboxylic acid early strength water reducing agent was purchased from Kunming Baiyi Building Materials Manufacturing Co., Ltd., model: G454.

[0033] Modified desert sand is prepared by modifying desert sand with a modifier.

[0034] The modified liquid is a compound of water, stearamidopropyl dimethyl tertiary amine, dodecyl trimethyl ammonium bromide and benzalkonium bromide.

[0035] Stearamidopropyl dimethyl tertiary amine is commercially available, CAS number: 7651-02-7.

[0036] Dodecyltrimethylammonium bromide is commercially available, CAS number: 1119-94-4.

[0037] Benzalkonium bromide is commercially available, CAS number: 7281-04-1.

[0038] Desert sand was commercially available with a particle size of 0.1-0.2 mm.

[0039] The preparation method of modified desert sand comprises the following steps: Step 1), 900kg water, 27kg stearamidopropyl dimethyl tertiary amine, 48kg dodecyltrimethylammonium bromide, 12kg benzalkonium bromide were put into a stirring tank, the speed was 120r / min, stirred for 10min, mixed evenly, and obtained a modified liquid.

[0040] Step 2), take 600 kg of modified liquid and put it into a stirring tank, then put in 300 kg of desert sand, heat to 50°C, rotate at 60 r / min, stir for 90 minutes, filter through filter cloth, take solid, and air-dry naturally to obtain modified desert sand.

[0041] The preparation method of the impermeable concrete containing polycarboxylic acid early strength water reducing agent comprises the following steps: Step 01), put 310kg cement, 33kg fly ash, 300kg fine aggregate, 670kg coarse aggregate, 210kg modified desert sand, and 5.7kg polycarboxylic acid early strength water reducing agent into a stirring tank, rotate at 60r / min, stir for 15min, stir evenly, and obtain a premix.

[0042] Step 02), add 100kg water to the premix, rotate at 60r / min, stir for 5min, stir evenly, and obtain concrete mixture.

[0043] Step 03), inject the concrete mixture into the mold, sprinkle water for 3 days, demould, sprinkle water for 7 days, and stand for 28 days to obtain the impermeable concrete containing polycarboxylic acid early strength water reducing agent.

[0044] Example 2 An impermeable concrete containing a polycarboxylate early strength water reducing agent comprises the following components in parts by weight: Water, cement, fly ash, fine aggregate, coarse aggregate, modified desert sand, polycarboxylic acid early strength water reducing agent.

[0045] The cement is ordinary Portland cement, Jidong cement, specification, P.O42.5.

[0046] The fly ash is sourced from commercially available, first-grade fly ash.

[0047] Fine aggregate comes from commercially available natural river sand with a particle size of 3-5 mm.

[0048] The coarse aggregate was obtained from commercially available basalt crushed stone with a particle size of 15-20 mm.

[0049] Polycarboxylic acid early strength water reducing agent was purchased from Kunming Baiyi Building Materials Manufacturing Co., Ltd., model: G454.

[0050] Modified desert sand is prepared by modifying desert sand with a modifier.

[0051] The modified liquid is a compound of water, stearamidopropyl dimethyl tertiary amine, dodecyl trimethyl ammonium bromide and benzalkonium bromide.

[0052] Stearamidopropyl dimethyl tertiary amine is commercially available, CAS number: 7651-02-7.

[0053] Dodecyltrimethylammonium bromide is commercially available, CAS number: 1119-94-4.

[0054] Benzalkonium bromide is commercially available, CAS number: 7281-04-1.

[0055] Desert sand was commercially available with a particle size of 0.1-0.2 mm.

[0056] The preparation method of modified desert sand comprises the following steps: Step 1), 900kg water, 30kg stearamidopropyl dimethyl tertiary amine, 51kg dodecyltrimethylammonium bromide, 15kg benzalkonium bromide were put into a stirring tank, the speed was 120r / min, stirred for 10min, mixed evenly, and obtained a modified liquid.

[0057] Step 2), take 750kg of modified liquid and put it into a stirring tank, then put in 300kg of desert sand, heat to 55°C, rotate at 60r / min, stir for 105min, filter through filter cloth, take solid, and air dry naturally to obtain modified desert sand.

[0058] The preparation method of the impermeable concrete containing polycarboxylic acid early strength water reducing agent comprises the following steps: Step 01), put 315kg cement, 35kg fly ash, 305kg fine aggregate, 675kg coarse aggregate, 215kg modified desert sand, and 5.9kg polycarboxylic acid early strength water reducing agent into a stirring tank, rotate at 60r / min, stir for 15min, stir evenly, and obtain a premix.

[0059] Step 02), add 100kg water to the premix, rotate at 60r / min, stir for 5min, stir evenly, and obtain concrete mixture.

[0060] Step 03), inject the concrete mixture into the mold, sprinkle water for 3 days, demould, sprinkle water for 7 days, and stand for 28 days to obtain the impermeable concrete containing polycarboxylic acid early strength water reducing agent.

[0061] Example 3 An impermeable concrete containing a polycarboxylate early strength water reducing agent comprises the following components in parts by weight: Water, cement, fly ash, fine aggregate, coarse aggregate, modified desert sand, polycarboxylic acid early strength water reducing agent.

[0062] The cement is ordinary Portland cement, Jidong cement, specification, P.O42.5.

[0063] The fly ash is sourced from commercially available, first-grade fly ash.

[0064] Fine aggregate comes from commercially available natural river sand with a particle size of 3-5 mm.

[0065] The coarse aggregate was obtained from commercially available basalt crushed stone with a particle size of 15-20 mm.

[0066] Polycarboxylic acid early strength water reducing agent was purchased from Kunming Baiyi Building Materials Manufacturing Co., Ltd., model: G454.

[0067] Modified desert sand is prepared by modifying desert sand with a modifier.

[0068] The modified liquid is a compound of water, stearamidopropyl dimethyl tertiary amine, dodecyl trimethyl ammonium bromide and benzalkonium bromide.

[0069] Stearamidopropyl dimethyl tertiary amine is commercially available, CAS number: 7651-02-7.

[0070] Dodecyltrimethylammonium bromide is commercially available, CAS number: 1119-94-4.

[0071] Benzalkonium bromide is commercially available, CAS number: 7281-04-1.

[0072] Desert sand was commercially available with a particle size of 0.1-0.2 mm.

[0073] The preparation method of modified desert sand comprises the following steps: Step 1), 900kg water, 33kg stearamidopropyl dimethyl tertiary amine, 54kg dodecyltrimethylammonium bromide, 18kg benzalkonium bromide were put into a stirring tank, the speed was 120r / min, stirred for 10min, mixed evenly, and obtained a modified liquid.

[0074] Step 2), 900 kg of the modified liquid is put into a stirring tank, and then 300 kg of desert sand is put into the stirring tank, heated to 60°C, rotated at 60 r / min, stirred for 120 min, filtered through a filter cloth, and the solid was taken and naturally air-dried to obtain modified desert sand.

[0075] The preparation method of the impermeable concrete containing polycarboxylic acid early strength water reducing agent comprises the following steps: Step 01), put 320kg cement, 37kg fly ash, 310kg fine aggregate, 680kg coarse aggregate, 220kg modified desert sand, and 6.1kg polycarboxylic acid early strength water reducing agent into a stirring tank, rotate at 60r / min, stir for 15min, stir evenly, and obtain a premix.

[0076] Step 02), add 100kg water to the premix, rotate at 60r / min, stir for 5min, stir evenly, and obtain concrete mixture.

[0077] Step 03), inject the concrete mixture into the mold, sprinkle water for 3 days, demould, sprinkle water for 7 days, and stand for 28 days to obtain the impermeable concrete containing polycarboxylic acid early strength water reducing agent.

[0078] Comparative Example 1 An impermeable concrete containing a polycarboxylic acid early strength water reducing agent, compared with Example 2, the only difference is: In the modified liquid, sodium dodecylbenzene sulfonate is used to replace stearylamidopropyl dimethyl tertiary amine in equal amounts.

[0079] Sodium dodecylbenzenesulfonate is commercially available, CAS number: 25155-30-0.

[0080] Comparative Example 2 An impermeable concrete containing a polycarboxylic acid early strength water reducing agent, compared with Example 2, the only difference is: In the modified solution, diglycolamine is used to replace dodecyltrimethylammonium bromide in equal amounts.

[0081] Diglycolamine is commercially available, CAS number: 929-06-6.

[0082] Comparative Example 3 An impermeable concrete containing a polycarboxylic acid early strength water reducing agent, compared with Example 2, the only difference is: In the modified solution, an equal amount of isomeric tridecanol polyoxyethylene ether is used to replace benzalkonium bromide.

[0083] Isomeric tridecanol polyoxyethylene ether is commercially available, CAS number: 9043-30-5.

[0084] Comparative Example 4 An impermeable concrete containing a polycarboxylic acid early strength water reducing agent, compared with Example 2, the only difference is: In the modified liquid, sodium dodecylbenzenesulfonate is used to replace stearylamidopropyl dimethyl tertiary amine in an equal amount; diglycolamine is used to replace dodecyltrimethylammonium bromide in an equal amount; and isomeric tridecanol polyoxyethylene ether is used to replace benzalkonium bromide in an equal amount.

[0085] Sodium dodecylbenzenesulfonate is commercially available, CAS number: 25155-30-0.

[0086] Diglycolamine is commercially available, CAS number: 929-06-6.

[0087] Isomeric tridecanol polyoxyethylene ether is commercially available, CAS number: 9043-30-5.

[0088] Comparative Example 5 An impermeable concrete containing a polycarboxylate early strength water reducing agent comprises the following components in parts by weight: Water, cement, fly ash, fine aggregate, coarse aggregate, desert sand, polycarboxylic acid early strength water reducing agent.

[0089] The cement is ordinary Portland cement, Jidong cement, specification, P.O42.5.

[0090] The fly ash is sourced from commercially available, first-grade fly ash.

[0091] Fine aggregate comes from commercially available natural river sand with a particle size of 3-5 mm.

[0092] The coarse aggregate was obtained from commercially available basalt crushed stone with a particle size of 15-20 mm.

[0093] Polycarboxylic acid early strength water reducing agent was purchased from Kunming Baiyi Building Materials Manufacturing Co., Ltd., model: G454.

[0094] Desert sand was commercially available with a particle size of 0.1-0.2 mm.

[0095] The preparation method of the impermeable concrete containing polycarboxylic acid early strength water reducing agent comprises the following steps: Step 01), put 315kg cement, 35kg fly ash, 305kg fine aggregate, 675kg coarse aggregate, 215kg desert sand, and 5.9kg polycarboxylic acid early strength water reducing agent into a stirring tank, rotate at 60r / min, stir for 15min, stir evenly, and obtain a premix.

[0096] Step 02), add 100kg water to the premix, rotate at 60r / min, stir for 5min, stir evenly, and obtain concrete mixture.

[0097] Step 03), inject the concrete mixture into the mold, sprinkle water for 3 days, demould, sprinkle water for 7 days, and stand for 28 days to obtain the impermeable concrete containing polycarboxylic acid early strength water reducing agent.

[0098] Comparative Example 6 An impermeable concrete containing a polycarboxylate early strength water reducing agent comprises the following components in parts by weight: Water, cement, fly ash, fine aggregate, coarse aggregate, polycarboxylic acid early strength water reducing agent.

[0099] The cement is ordinary Portland cement, Jidong cement, specification, P.O42.5.

[0100] The fly ash is sourced from commercially available, first-grade fly ash.

[0101] Fine aggregate comes from commercially available natural river sand with a particle size of 3-5 mm.

[0102] The coarse aggregate was obtained from commercially available basalt crushed stone with a particle size of 15-20 mm.

[0103] Polycarboxylic acid early strength water reducing agent was purchased from Kunming Baiyi Building Materials Manufacturing Co., Ltd., model: G454.

[0104] The preparation method of the impermeable concrete containing polycarboxylic acid early strength water reducing agent comprises the following steps: Step 01), put 315kg cement, 35kg fly ash, 405kg fine aggregate, 790kg coarse aggregate, and 5.9kg polycarboxylic acid early strength water reducing agent into a stirring tank, rotate at 60r / min, stir for 15min, stir evenly, and obtain a premix.

[0105] Step 02), add 100kg water to the premix, rotate at 60r / min, stir for 5min, stir evenly, and obtain concrete mixture.

[0106] Step 03), inject the concrete mixture into the mold, sprinkle water for 3 days, demould, sprinkle water for 7 days, and stand for 28 days to obtain the impermeable concrete containing polycarboxylic acid early strength water reducing agent.

[0107] Experiment 1 According to GB / T50081-2019 "Standard for Test Methods for Physical and Mechanical Properties of Concrete", the 7d compressive strength (standard specimen) and 28d compressive strength (standard specimen) of the samples made of the anti-seepage concrete containing polycarboxylic acid early strength water reducer in each embodiment and comparative example were tested.

[0108] Experiment 2 According to GB / T50082-2009 "Standard for Test Methods for Long-term Performance and Durability of Ordinary Concrete", the step-by-step pressurization method in the water penetration resistance test was used to detect the impermeability grade of the samples made from the impermeable concrete containing polycarboxylic acid early strength water reducing agent in each embodiment and comparative example.

[0109] The specific test data of Experiment 1-2 are shown in Table 1.

[0110] Table 1 According to the data comparison of each embodiment and the comparative example in Table 1, it can be obtained that the compressive strength and the impermeability grade of each embodiment are significantly higher than those of each comparative example. It can be seen that after the desert sand is modified by the modified liquid prepared by mixing stearamidopropyl dimethyl tertiary amine, dodecyltrimethylammonium bromide and benzalkonium bromide in each embodiment, the influence on the viscosity of the cement slurry can be reduced while adding a large amount of desert sand, so that the cement slurry and desert sand can penetrate into the gap between the aggregates well, thereby greatly improving the density of the concrete, and the strength and impermeability of the concrete are significantly improved.

[0111] Although comparative examples 1-4 also modified the desert sand, the strength and impermeability of the concrete were higher than those of comparative examples 5 and 6. However, due to the destruction of the composite system of stearamidopropyl dimethyl tertiary amine, dodecyltrimethylammonium bromide and benzalkonium bromide, the modification effect was poor, and the strength and impermeability of the concrete were significantly weaker than those of the embodiments.

[0112] Comparative Example 5 did not modify the desert sand, and the compressive strength of Comparative Example 5 was significantly lower than that of Comparative Example 6. The impermeability of Comparative Example 5 was similar to that of Comparative Example 6. It can be seen that the large amount of unmodified desert sand added is difficult to improve the impermeability of concrete, and will also cause the strength of concrete to decrease.

[0113] This specific embodiment is merely an explanation of the present application and is not a limitation of the present application. After reading this specification, those skilled in the art may make modifications to the present embodiment without any creative contribution as needed, but such modifications are protected by the patent law as long as they are within the scope of the claims of the present application.

Claims

1. An anti-permeability concrete containing a polycarboxylic acid early strength water reducing agent, characterized in that: The composition includes the following components in parts by weight: 100 parts water; 310-320 parts of cement; Fly ash 33-37 parts; 300-310 parts of fine aggregate; 670-680 parts of coarse aggregate; 210-220 parts of modified desert sand; 5.7-6.1 parts of polycarboxylic acid early strength water reducing agent; The modified desert sand is prepared by modifying desert sand with a modifier; The modified liquid is a compound of water, stearamidopropyl dimethyl tertiary amine, dodecyl trimethyl ammonium bromide and benzalkonium bromide.

2. The anti-seepage concrete containing polycarboxylic acid early strength water reducing agent according to claim 1, characterized in that: The mass ratio of stearamidopropyl dimethyl tertiary amine, dodecyltrimethylammonium bromide and benzalkonium bromide is 9-11:16-18:4-6.

3. The anti-seepage concrete containing polycarboxylic acid early strength water reducing agent according to claim 2, characterized in that: The mass ratio of the water, stearamidopropyl dimethyl tertiary amine, dodecyltrimethylammonium bromide and benzalkonium bromide is 300:9-11:16-18:4-6.

4. The anti-seepage concrete containing polycarboxylic acid early strength water reducing agent according to claim 3, characterized in that: The particle size of the desert sand is 0.1-0.2 mm.

5. The anti-seepage concrete containing polycarboxylic acid early strength water reducing agent according to claim 4, characterized in that: The preparation method of the modified desert sand comprises the following steps: Step 1), water, stearamidopropyl dimethyl tertiary amine, dodecyl trimethyl ammonium bromide, and benzalkonium bromide are uniformly mixed to obtain a modified solution; Step 2), adding desert sand into the modified liquid, stirring for 90-120 minutes, filtering and drying to obtain modified desert sand.

6. The anti-seepage concrete containing polycarboxylic acid early strength water reducing agent according to claim 5, characterized in that: In the step 2), after adding the desert sand into the modified liquid, it is first heated to 50-60° C. and then stirred for 90-120 minutes.

7. The anti-seepage concrete containing polycarboxylic acid early strength water reducing agent according to claim 6, characterized in that: In the step 2), the mass ratio of desert sand to modifying liquid is 1:2-3.

8. A method for preparing an impermeable concrete containing a polycarboxylic acid early strength and water reducing agent according to any one of claims 1 to 7, characterized in that: The following steps are involved: Step 01), cement, fly ash, fine aggregate, coarse aggregate, modified desert sand, and polycarboxylic acid early strength water reducing agent are mixed evenly to obtain a premix; Step 02), adding water to the premix and stirring evenly to obtain a concrete mixture; Step 03), injecting the concrete mixture into the mold, curing, and demoulding to obtain the impermeable concrete containing the polycarboxylic acid early strength water reducing agent.

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