Large-flow-state cement-based material anti-bleeding agent as well as preparation and use methods thereof

Abstract

The invention discloses a large-flow-state cement-based material anti-bleeding agent as well as a preparation method and a use method thereof, and belongs to the technical field of building materials. Comprising the following raw materials in parts by weight: 20-30 parts of building solid waste regenerated powder, 5-10 parts of water-absorbent resin, 35-52 parts of a water-retaining suspension stabilizer, 1-6 parts of diethanol amine, 10-15 parts of maltodextrin, 1-2 parts of anhydrous cocamidopropyl betaine, 2-5 parts of sodium alpha-olefin sulfonate and 1-5 parts of an organic silicon defoaming agent. The large-flow cement-based material anti-bleeding agent provided by the invention can effectively absorb excessive moisture in a cement-based material, improves the dispersity, cohesiveness and fluidity of the cement-based material, and has the advantages of quick effect, simplicity and convenience in implementation and operation, and capability of coping with bleeding of different degrees.

Description

Technical Field

[0001] The present invention belongs to the technical field of building materials, and particularly relates to a bleeding water inhibitor for high-fluidity cement-based materials, and a preparation and use method thereof. Background Art

[0002] Cement-based materials, including cement concrete, cement mortar and neat cement paste materials, are important application materials in the field of engineering construction. They have the characteristics of low cost, high strength, good durability, etc. In order to improve construction efficiency and facilitate shaping, most cement concrete, mortar and neat cement paste materials adopt a relatively high fluidity, including but not limited to: ① Pumped concrete / mortar, which uses pumped construction, greatly facilitating the transportation and placement of concrete / mortar into the formwork, and also greatly improving the forming speed; ② Self-leveling concrete / mortar, relying on its good fluidity, after pouring, the pouring surface can be leveled without vibration. Its slump requirement is ≥230 mm, the spread requirement is ≥600 mm, and the spread time of the inverted slump cone is ≤5 s; ③ Vibration-free concrete, which can meet the strength requirements, impermeability and various durability requirements without vibration for forming; ④ Self-compacting concrete, which can achieve a high degree of compaction without vibration, meeting the requirements for strength and durability of concrete; ⑤ Underwater cast-in-place pile concrete, making full use of the fluidity of concrete, while discharging in the underwater pile, it is also necessary to ensure the cohesiveness of the concrete underwater and form a high strength when setting underwater; ⑥ Cement-based grouting / pressing / grouting materials, in order to make the cement slurry fully fill the voids and play a role in bonding and fixing, it must reach a relatively high fluidity state and be evenly dispersed without bleeding and delamination. From the above cement-based materials, a relatively high fluidity can not only facilitate the transportation of materials, but also reduce the energy consumption during the material forming process, and most conveniently the construction process to the greatest extent. However, a high fluidity often requires a relatively large amount of water. In the process of cement hydration reaction, water is an important component. It not only participates in the chemical reaction of the cement strength increase process, but also provides the basis for the fluidity of the cement-based materials. However, the density of water is much smaller than that of cement. Therefore, once there is too much water, bleeding of different degrees is likely to occur. Bleeding refers to the phenomenon that due to the much lower density of water in the mixture compared to the cementitious materials and sand and gravel, the cementitious materials and sand and gravel sink, and the water floats up and seeps out from the surface of the mixture. Therefore, for the characteristics of high-fluidity cement-based materials with a large water demand, due to the fluctuations in the water content of each raw material, different water demand and fluidity ratios, the bleeding phenomenon often occurs, only to different degrees.

[0003] Slight bleeding is very common during the application of cement-based materials. If the surface treatment and curing methods are in place during molding, it has basically no adverse effect on the quality of concrete. However, when the bleeding rate exceeds a certain level, it will have a greater deteriorating effect on the material quality. Aggregates sink, the surface water-cement ratio suddenly increases, seriously affecting the uniformity of the mixture, and the strength and durability will deteriorate. The inconsistent water-cement ratio is likely to cause a large difference in volume change due to temperature change, resulting in serious cracking. The sinking of aggregates will also cause obvious settlement shrinkage and cracking. On this basis, if the bleeding degree increases further, it will seriously affect the construction of the material, leading to the blockage of conveying equipment. Even if it is poured and formed, the material is extremely prone to honeycombing and pitting, causing serious economic losses. It can be seen that bleeding is an important index that needs to be strictly controlled during the production and construction of cement-based materials.

[0004] At present, for the bleeding of cement-based materials, it is generally processed by reprocessing the returned materials, and there is no direct and effective material for on-site improvement. This not only delays the construction time, but also affects the original ratio of the material, posing a risk to quality control. During the production process of cement-based materials, due to: ① the different water contents of sand and stone, the water consumption is also different. Moreover, during the stacking process of sand and stone, the water content in the lower part is often higher than that in the upper part, and the water consumption cannot be adjusted in real time during the production process, resulting in fluctuations in the water content of the mixture; ② different lithologies of sand and stone result in different saturated surface dry water absorption rates. Even when the actual water consumption remains unchanged, it will cause differences in the fluidity of the mixture, and the bleeding rate will also change accordingly; ③ the fluctuations in the standard consistency of cement, the water demand of admixtures such as fly ash and slag powder, the fluidity ratio, and the changes in the fineness of these powders will greatly affect the bleeding rate of the final mixture. In addition to the above key factors, the sphericity of aggregates, the MB value of sand and stone, and excessive vibration during construction will all cause bleeding of varying degrees to the final cement-based mixture material, increasing the quality risk.

[0005] Therefore, how to provide an additive that can improve the bleeding problem of cement-based materials and effectively reduce the bleeding rate of the material after being stirred and added is a technical problem that needs to be urgently solved by those skilled in the art. Summary of the Invention

[0006] To solve the above technical problems, the present invention proposes a high-fluidity cement-based material bleeding inhibitor and its preparation and use methods.

[0007] To achieve the above object, the present invention provides the following technical solutions:

[0008] A high-fluidity cement-based material bleeding inhibitor, comprising the following raw materials in parts by weight:

[0009] 20-30 parts of construction waste recycled powder, 5-10 parts of water-absorbing resin, 35-52 parts of water-retaining suspension stabilizer, 1-6 parts of diethanolamine, 10-15 parts of maltodextrin, 1-2 parts of anhydrous coconut oil amide propyl betaine, 2-5 parts of α-olefin sulfonate, and 1-5 parts of silicone defoamer.

[0010] Preferably, the specific surface area of the construction waste recycled powder ≥ 500m 2 / kg, which is ground from construction waste recycled sand powder that meets the Class B technical requirements in the standard JCT 2548-2019 "Construction Waste Recycled Sand Powder".

[0011] Preferably, the water demand ratio of the construction waste recycled sand powder < 2.0 and > 1.8.

[0012] Beneficial effects: The construction waste recycled powder in the present invention is ground from construction waste recycled sand powder that meets the Class B technical requirements in the standard JCT 2548-2019 "Construction Waste Recycled Sand Powder". The water demand ratio of the construction waste recycled sand powder must meet < 2.0 and > 1.8. After grinding, the specific surface area ≥ 500m 2 / kg. Since the water demand ratio of Class B construction waste recycled sand powder is relatively high, under the same fluidity requirements, more water is needed. On this basis, further grinding is carried out to increase the specific surface area to more than 500m 2 / kg, which can effectively utilize the excess exuded water. While ensuring the fluidity of the cement-based material, water bleeding is reduced and the water retention of the material is increased. In addition, construction waste recycled sand powder usually also has good compatibility with polycarboxylate water reducers, reducing water bleeding caused by the increase in admixtures and also playing a partial viscosity reduction role.

[0013] Secondly, the water-absorbing resin in the present invention has good adsorption properties and can adsorb the excess water in the cement-based material; diethanolamine can mainly improve the hydration rate of cement, make up for the delay in cement setting time caused by guar gum modified polysaccharides, make the setting time of the cement-based material to be adjusted tend to be normal, and at the same time play a partial early strength and accelerating setting role. The excess exuded water increases the water-cement ratio of the material, which is not conducive to strength development. Therefore, this component effectively solves this problem; maltodextrin should meet the technical requirements of MD20 in the national standard GB / T20884-2007 "Maltodextrin", and mainly plays a role in adjusting the adhesion of the cement-based material. Due to water bleeding, the cement-based material is prone to layering, making the adhesion of the cement-based material to other materials poor, and improving the bonding of the two materials; the colloidal material in the present invention can improve the viscosity and dispersibility of the cement paste and other properties, and improve the uniformity of the concrete; α-olefin sulfonate (AOS) is made from α-olefins in SO 3The anionic surfactant prepared by gas-phase membrane sulfonation and continuous neutralization can introduce a small amount of fine bubbles, reduce the viscosity of the mixture, and reduce the problem of excessive viscosity caused by colloidal materials; anhydrous coconut oil amide propyl betaine is a zwitterionic surfactant with good performance. It is a powder prepared from coconut oil, N,N-dimethylpropylenediamine, and sodium chloroacetate as raw materials and dried. It can improve the foam stability of the above-mentioned AOS, ensure that the microbubbles introduced have good persistence before the initial setting time of the cement, and the mixture can always maintain the characteristics of uniformity, large fluidity, and low viscosity; the silicone defoamer should meet the technical requirements of the ordinary solid type in the national standard GB / T 26527-2024 "Silicone Defoamer", and can reduce the content of large bubbles in the system and increase the density of the cement-based material.

[0014] Preferably, the water retention suspension stabilizer is a low-molecular-weight non-ionic polysaccharide polymer, prepared by modifying guar gum. The specific preparation method includes the following steps:

[0015] After removing the skin and germ of the guar bean seeds, they are dried, crushed, added with water, subjected to pressure hydrolysis, precipitated with 20% ethanol, centrifuged and separated, and then dried and crushed to obtain the water retention suspension stabilizer.

[0016] Beneficial effects: The main components of the water retention suspension stabilizer in the present invention are composed of galactose and mannose. In the bleeding concrete, due to the excessive precipitation of water, the viscosity of the mixture is inconsistent. The addition of the modified guar gum polysaccharide can improve the cohesiveness of the cement paste, and at the same time increase the viscosity of the mixture. In addition, its addition will slightly extend the setting time of the cement paste.

[0017] Preferably, the water-absorbing resin is a starch-grafted acrylate polymer crosslinking agent and an acrylamide-acrylate copolymer crosslinking agent.

[0018] Preferably, the mass ratio of the starch-grafted acrylate polymer crosslinking agent to the acrylamide-acrylate copolymer crosslinking agent is (0.34-0.37):1.

[0019] Beneficial effects: The water-absorbing resin in the present invention can adsorb the excess water in the bleeding cement-based mixture to form a gel, reducing the bleeding rate of the cement-based material. However, it will also increase the viscosity of the mixture. Although the acrylamide-acrylate copolymer crosslinking agent has a good water absorption rate, the viscosity increases, and it will reduce the wrapping property of the cement paste and the aggregate, reducing the fluidity of the cement-based mixture, which is not conducive to the application of the large fluidity materials applicable in the present invention. Therefore, adding a part of the starch-grafted acrylate polymer crosslinking agent can ensure the water absorption rate while ensuring the fluidity of the mixture.

[0020] A preparation method of a high-fluidity cement-based material anti-bleeding agent. After weighing the raw materials and mixing them evenly, the high-fluidity cement-based material anti-bleeding agent is obtained.

[0021] A usage method of a high-fluidity cement-based material anti-bleeding agent, including the following steps:

[0022] Detect the bleeding rate of the cement-based material, and then add the anti-bleeding agent to the cement-based material while stirring according to the severity of bleeding until the bleeding level is reduced to within the construction requirements.

[0023] A detection method of a high-fluidity cement-based material anti-bleeding agent. Corresponding to the bleeding rate reduction value, this value is detected by the following method: ΔB = 4% - Bc;

[0024] Where: ΔB is the bleeding rate reduction value;

[0025] 4% is the over-dosage of water consumption, making the bleeding rate reach 4%;

[0026] Bc is the bleeding rate of the concrete after over-dosage of water consumption to make the bleeding rate reach 4% and then adding the anti-bleeding agent.

[0027] Preferably, in the Bc, the dosage of the added anti-bleeding agent is 80g / m 3 .

[0028] Preferably, the ΔB is > 3.5%.

[0029] The test results are expressed as the average value of the measured values of three batches of tests. If the difference between the maximum or minimum value and the intermediate value of one batch among the three batches of tests exceeds 15% of the intermediate value, then both the maximum value and the minimum value are discarded, and the intermediate value is taken as the test result of this batch. If the differences between the measured values of two batches and the intermediate value both exceed 15% of the intermediate value, then the test results are invalid and should be redone.

[0030] Beneficial effects: The bleeding rate of cement-based materials such as concrete and cement-based grouting materials is tested and calculated according to GBT50080. Under the mixing ratio conditions of ordinary concrete and cement-based grouting materials, over-dosage of water consumption, and the specific dosage is such that the bleeding rate of concrete and cement-based grouting materials is 4%. Then add the anti-bleeding agent provided by the present invention, and the dosage of the added anti-bleeding agent is such that ΔB > 3.5%. Within this range, the cement-based material can meet better uniformity, workability, reduce the uneven water-cement ratio caused by surface bleeding, surface strength loss, and cracking caused by uneven volume change and other adverse phenomena.

[0031] Compared with the prior art, the present invention has the following advantages and technical effects:

[0032] The anti-bleeding agent for high-fluidity cement-based materials provided by the present invention can effectively absorb the excess water in the cement-based materials, while improving the dispersibility, cohesion and fluidity of the cement-based materials, reducing the strength loss caused by the excess water, ensuring the durability of the cement-based materials, and having the advantages of quick effect, simple and convenient implementation operation, and being able to cope with bleeding to different degrees. In addition, the product preparation method provided by the present invention is simple, only needs to mix the raw materials to obtain, is convenient to apply at the construction site, and greatly saves manpower and material resources. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] The drawings constituting a part of this application are used to provide a further understanding of this application. The schematic embodiments and descriptions thereof of this application are used to explain this application and do not constitute an improper limitation to this application. In the drawings:

[0034] Figure 1 It is a physical photo of the concrete mixing state before adding the anti-bleeding agent in Application Example 1;

[0035] Figure 2 It is a physical photo of the concrete mixing state after adding the anti-bleeding agent in Application Example 1. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0036] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0037] To make the above objects, features and advantages of the present invention more obvious and understandable, the present invention will be further described in detail below in conjunction with the specific embodiments.

[0038] Unless otherwise specified, the raw materials in the embodiments of the present invention are all obtained through commercial channels;

[0039] Among them, the construction waste recycled powder is the fine powder ground from the construction waste recycled sand powder, with a specific surface area ≥ 500 m 2 / kg, and the waste recycled sand powder is a Class B product that meets the standard JCT 2548-2019 for construction waste recycled sand powder, and the water demand ratio must meet < 2.0 and > 1.8;

[0040] The water-absorbing resin is obtained by mixing starch-grafted acrylate polymer crosslinking agent and acrylamide-acrylate copolymer crosslinking agent in a mass ratio of 0.34 - 0.37:1;

[0041] The water retention suspension stabilizer is a low molecular weight non-ionic polysaccharide polymer, prepared by modifying guar gum, and the specific preparation method includes the following steps:

[0042] The guar bean seeds are peeled and degerminated, dried and crushed, and then water is added. The guar bean seeds are hydrolyzed under pressure at 0.45 MPa and 35-45° C. for 3 hours. The seeds are precipitated with 20% ethanol, centrifuged, dried, and crushed to obtain the water-retaining suspension stabilizer.

[0043] Starch grafted acrylate polymer cross-linked products were purchased from Hubei Maidehao Biotechnology Co., Ltd.;

[0044] Acrylamide-acrylate copolymer cross-linked products were purchased from Hangzhou Yuhao Chemical Technology Co., Ltd.;

[0045] The organosilicon powder defoamer was purchased from Beijing Zhubao New Technology Co., Ltd.

[0046] In the embodiment of the present invention, the reduction value of water seepage rate of cement-based materials such as concrete, mortar, and paste is calculated according to formula (1):

[0047] ΔB=4%-B C (1)

[0048] Where:

[0049] ΔB: reduction in water seepage rate;

[0050] 4%: Use excessive water to make the water seepage rate reach 4%;

[0051] B C : The water content is exceeded to make the water seepage rate reach 4% and then the recommended amount of anti-seepage agent is added.

[0052] The test results are expressed as the average of the three batches of test values. If the difference between the maximum or minimum value and the middle value of one batch of three batches exceeds 15% of the middle value, the maximum and minimum values ​​are discarded and the middle value is taken as the test result of the batch. If the difference between the measured values ​​of two batches and the middle value exceeds 15% of the middle value, the test results are invalid and need to be retested and calculated.

[0053] The water seepage rate of cement-based materials is tested and calculated using GBT50080. Under the conditions of the proportion of ordinary concrete and cement-based grouting materials, the amount of water is over-dosed, and the specific amount of water added is such that the water seepage rate of concrete and cement-based grouting materials is 4%. The amount of anti-water seepage agent added is 80kg / m 3 , making ΔB>3.5%.

[0054] Example 1

[0055] A high-fluidity cement-based material anti-seepage agent, comprising the following raw materials in parts by weight:

[0056] 25 parts of construction waste incineration recycled powder, 10 parts of water-absorbing resin, 39 parts of water-retaining suspension stabilizer, 4 parts of diethanolamine, 12 parts of maltodextrin, 2 parts of anhydrous coconut oil amide propyl betaine, 5 parts of α-olefin sulfonate and 3 parts of silicone defoamer.

[0057] Mix the above raw materials evenly under dry conditions and seal them with waterproof and moisture-proof packaging bags to obtain the water secretion inhibitor.

[0058] Use the formula ΔB = 4% - B C Calculate the reduction value of the bleeding rate to detect whether the above water secretion inhibitor is qualified. Among them, the dosage of the water secretion inhibitor is 80 kg / m 3 , and finally calculate that ΔB is 3.8%.

[0059] Application Example 1

[0060] Use pumped C30 concrete for construction. Among them, the pumped C30 concrete includes the following raw materials in parts by weight: 270 parts of cement, 90 parts of fly ash, 160 parts of water, 860 parts of sand, 1040 parts of crushed stone, and 5.6 parts of admixture (polycarboxylate superplasticizer powder of HPWR-S type in concrete admixtures in accordance with standard GB8076-2008). During the construction process, bleeding occurred in the concrete. The reasons for bleeding included weighing system errors in water consumption, fluctuations in sand moisture content, and changes in the saturated surface dry water absorption rate of sand. According to the standard GBT50080-2016 Standard Test Method for Properties of Ordinary Concrete Mixtures, it was measured that: the bleeding rate reached 4.2%, and the slump, spread index, and inverted slump cone emptying time index could not be measured normally. The concrete bled severely and could not be formed. For details, see Figure 1 .

[0061] Add 50 g / m 3 (that is, the addition amount per square meter of C30 concrete is 50 g) of the water secretion inhibitor obtained in Example 1 to the above pumped C30 concrete. After that, the bleeding rate of the concrete was directly reduced to 0.1%, and the slump and spread reached 220 mm and 550 mm respectively. The inverted slump cone emptying time was 5.5 s. The fluidity was good, the viscosity was low, and it met the requirements of pumped construction. And the final setting time was 9.5 h, the 7-day and 28-day compressive strengths reached 29.5 MPa and 38.8 Mpa respectively, and the impermeability performance also reached P10 level, meeting the construction and acceptance requirements. The adjusted state of the concrete mixture is as Figure 2 shown.

[0062] Example 2

[0063] A high-fluidity cement-based material water secretion inhibitor, including the following raw materials in parts by weight:

[0064] 30 parts of construction waste recycled powder, 10 parts of water-absorbing resin, 40 parts of water-retaining suspension stabilizer, 2 parts of diethanolamine, 10 parts of maltodextrin, 2 parts of anhydrous coconut oil amide propyl betaine, 3 parts of α-olefin sulfonate, and 3 parts of silicone defoamer.

[0065] Mix the above raw materials evenly under dry conditions and seal them with a waterproof and moisture-proof packaging bag to obtain the water secretion inhibitor.

[0066] Use the formula ΔB = 4% - B C Calculate the reduction value of the bleeding rate to detect whether the above water secretion inhibitor is qualified. Among them, the dosage of the water secretion inhibitor is 80 kg / m 3 , and finally the calculated ΔB is 3.8%.

[0067] Application Example 2

[0068] Use floor mortar for construction. Among them, the floor mortar includes the following raw materials in parts by weight: 400 parts of cement, 50 parts of fly ash, 220 parts of water, 1350 parts of sand, and 6.0 parts of admixture (polycarboxylate superplasticizer powder of HPWR-S type in concrete admixtures in accordance with standard GB8076-2008). During delivery inspection, the bleeding rate of the mortar is as high as 5.6%, and a layer of water is obviously secreted on the surface, resulting in an increase in the water-cement ratio on the surface, making this part of the surface mortar prone to cracking, carbonization, and dusting. According to JGJ 70-2009 Test Methods for Basic Properties of Building Mortars, the mortar consistency cannot be accurately measured and cannot meet the construction conditions.

[0069] Therefore, after adding 80 g / m 3 of the water secretion inhibitor obtained in Example 2 to the above floor mortar, the bleeding rate of the mortar is directly reduced to 0.2%, and the fluidity still meets the construction requirements. And the final setting time is 8.5 h, the consistency reaches 145 mm, meeting the technical requirements of self-leveling; the 7-day and 28-day compressive strengths reach 39.7 MPa and 49.9 MPa respectively.

[0070] Example 3

[0071] A high-fluidity cement-based material water secretion inhibitor, including the following raw materials in parts by weight:

[0072] 20 parts of construction waste recycled powder, 10 parts of water-absorbing resin, 42 parts of water-retaining suspension stabilizer, 5 parts of diethanolamine, 15 parts of maltodextrin, 1 part of anhydrous coconut oil amide propyl betaine, 2 parts of α-olefin sulfonate, and 4 parts of silicone defoamer.

[0073] Mix the above raw materials evenly under dry conditions and seal them with a waterproof and moisture-proof packaging bag to obtain the water secretion inhibitor.

[0074] Use the formula ΔB = 4% - B CCalculate the reduction value of bleeding rate to detect whether the above bleeding water reducer is qualified. Among them, the dosage of the bleeding water reducer is 80 kg / m 3 , and finally, ΔB is calculated to be 3.9%.

[0075] Application Example 3

[0076] Use cement grout for construction. Among them, the cement grout includes the following raw materials in parts by weight: 748 parts of cement, 150 parts of mineral powder, 150 parts of fly ash, 99 parts of silica fume, 153 parts of steel fiber, 740 parts of quartz powder, 170 parts of water, and 25 parts of admixture. Due to the fluctuation of the water demand ratio of raw materials and the admixture, bleeding occurs in the material, and the measured bleeding rate reaches 3.7%. The flow cone fluidity of the material cannot be measured according to the standard GBT 50448-2015 Technical Specification for Application of Cement-based Grouting Materials. The admixture is HPWR-S type polycarboxylate high-performance water reducer powder that meets the standard GB8076-2008 Concrete Admixtures.

[0077] After adding the bleeding water reducer obtained in Example 3 at 130 g / m 3 to the above cement grout, the bleeding rate of the grout is directly reduced to 0%, meeting the construction requirements. And the final setting time of the grout is 8 h, the flow cone fluidity reaches 15 s, and the 7-day compressive strength and 28-day compressive strength are 90.6 MPa and 116.3 MPa respectively.

[0078] Comparative Example 1

[0079] A bleeding water reducer, which is different from Example 1 in that the specific surface area of the construction waste recycled powder is only 320 m 2 / kg, lower than the required 500 m 2 / kg. Other raw materials, process steps and parameters are the same as those in Example 1.

[0080] Use the formula ΔB = 4% - B C to calculate the reduction value of bleeding rate to detect whether the above bleeding water reducer is qualified. Among them, the dosage of the bleeding water reducer is 80 kg / m 3 , and finally, ΔB is calculated to be 3.2%, less than the required 3.5%.

[0081] Comparative Application Example 1

[0082] The difference from Application Example 1 is that the water segregation inhibitor obtained in Example 1 is replaced with an equal amount of the water segregation inhibitor obtained in Comparative Example 1. Other process steps and parameters are the same as those in Example 1. The bleeding rate of the final concrete is reduced to 1.1%, and the slump and spread are restored to 160 mm and 360 mm respectively. The emptying time of the inverted slump cone is 17.8 s. The fluidity has improved but is still poor, and the viscosity is high, failing to meet the requirements for pumping construction. The final setting time is 14.0 h, the 7-day and 28-day compressive strengths are 18.9 MPa and 27.6 MPa respectively, and the impermeability performance fails to reach P10 level, unable to meet the construction and acceptance requirements.

[0083] Comparative Example 2

[0084] A water segregation inhibitor, different from Example 2 in that it does not include the water-absorbing resin. Other raw materials, process steps and parameters are the same as those in Example 2.

[0085] Using the formula ΔB = 4% - B C to calculate the reduction value of the bleeding rate to detect whether the above water segregation inhibitor is qualified, where the dosage of the water segregation inhibitor is 80 kg / m 3 , and finally the calculated ΔB is 2.5%.

[0086] Comparative Application Example 2

[0087] The difference from Comparative Application Example 2 is that the water segregation inhibitor obtained in Example 2 is replaced with an equal amount of the water segregation inhibitor obtained in Comparative Example 2. Other process steps and parameters are the same as those in Example 2. The bleeding rate of the final mortar is reduced to 1.7%, while the fluidity fails to meet the construction requirements. The final setting time is 12.5 h, the consistency reaches 75 mm, not meeting the technical requirements for self-leveling; the 7-day and 28-day compressive strengths reach 31.5 MPa and 37.7 MPa respectively.

[0088] Comparative Example 3

[0089] A water segregation inhibitor, different from Example 3 in that it does not include the water retention suspension stabilizer. Other raw materials, process steps and parameters are the same as those in Example 3.

[0090] Using the formula ΔB = 4% - B C to calculate the reduction value of the bleeding rate to detect whether the above water segregation inhibitor is qualified, where the dosage of the water segregation inhibitor is 80 kg / m 3 , and finally the calculated ΔB is 3.3%.

[0091] Comparative Application Example 3

[0092] The difference from Application Example 3 is that the water segregation inhibitor obtained in Example 3 is replaced with an equal amount of the water segregation inhibitor obtained in Comparative Example 3. Other process steps and parameters are the same as those in Example 3. The water segregation rate of the grouting material is reduced to 0.8%, which fails to meet the construction requirements. Moreover, the final setting time of the grouting material is 16 h, the flow cone fluidity reaches 32 s, and the 7-day compressive strength and 28-day compressive strength are 70.4 MPa and 85.7 MPa respectively.

[0093] Comparative Example 4

[0094] A water segregation inhibitor, different from that in Example 1, does not include construction waste recycled powder and water-absorbing resin. Other raw materials, process steps and parameters are the same as those in Example 1.

[0095] Using the formula ΔB = 4% - B C calculate the reduction value of the water segregation rate to detect whether the above water segregation inhibitor is qualified, where the dosage of the water segregation inhibitor is 80 kg / m 3 , and finally the calculated ΔB is 1.9%.

[0096] Comparative Application Example 4

[0097] The difference from Application Example 1 is that the water segregation inhibitor obtained in Example 1 is replaced with an equal amount of the water segregation inhibitor obtained in Comparative Example 4. Other process steps and parameters are the same as those in Example 1. Finally, the water segregation rate of the concrete is reduced to 2.1%, and the slump and spread are restored to 100 mm and 320 mm respectively, and the final setting time is 16.5 h, and the 7-day and 28-day compressive strengths are 15.4 MPa and 23.3 Mpa respectively. The impermeability performance fails to reach the P10 level and cannot meet the construction and factory inspection requirements.

[0098] Comparative Example 5

[0099] A water segregation inhibitor, different from that in Example 3, does not include diethanolamine and α-olefin sulfonate. Other raw materials, process steps and parameters are the same as those in Example 3.

[0100] Using the formula ΔB = 4% - B C calculate the reduction value of the water segregation rate to detect whether the above water segregation inhibitor is qualified, where the dosage of the water segregation inhibitor is 80 kg / m 3 , and finally the calculated ΔB is 3.3%.

[0101] Comparative Application Example 5

[0102] The difference from Application Example 3 is that the water repellent agent obtained in Example 3 is replaced with an equal amount of the water repellent agent obtained in Comparative Example 3. Other process steps and parameters are the same as those in Example 3. The bleeding rate of the grouting material is reduced to 0.8%, meeting the construction requirements. Moreover, the final setting time of the grouting material is 11.5 h, the flow cone fluidity reaches 26 s, and the 7-day compressive strength and 28-day compressive strength are 75.4 MPa and 99.7 MPa respectively, and the reduction in strength compared with Application Example 3 is relatively large.

[0103] The above are only the preferred specific embodiments of the present application, but the protection scope of the present application is not limited thereto. Any changes or substitutions that can be easily thought of by those skilled in the art within the technical scope disclosed in the present application should be covered by the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A high-fluidity cement-based material anti-seepage agent, characterized in that: The invention comprises the following raw materials in parts by weight: 20-30 parts of construction solid waste recycled powder, 5-10 parts of water-absorbing resin, 35-52 parts of water-retaining suspension stabilizer, 1-6 parts of diethanolamine, 10-15 parts of maltodextrin, 1-2 parts of anhydrous cocamidopropyl betaine, 2-5 parts of sodium α-olefin sulfonate and 1-5 parts of silicone defoamer.

2. The anti-seepage agent for high-fluidity cement-based materials according to claim 1, characterized in that: The specific surface area of ​​the construction solid waste recycled powder is ≥500m 2 / kg, which is made by grinding recycled sand powder from construction solid waste that meets the Class B technical requirements of the standard JCT 2548-2019 "Recycled Sand Powder from Construction Solid Waste".

3. The anti-seepage agent for high-fluidity cement-based materials according to claim 1, characterized in that: The water requirement ratio of the construction solid waste recycled sand powder is less than 2.0 and greater than 1.

8.

4. The anti-seepage agent for high-fluidity cement-based materials according to claim 1, characterized in that: The preparation method of the water-retaining suspension stabilizer comprises the following steps: The guar bean seeds are peeled and germ-free, dried and crushed, and then water is added. After pressure hydrolysis, 20% ethanol is used for precipitation. After centrifugal separation, the water-retaining suspension stabilizer is obtained by drying and crushing.

5. The anti-seepage agent for high-fluidity cement-based materials according to claim 1, characterized in that: The water-absorbing resin is obtained by mixing a starch-grafted acrylate polymer cross-linked product and an acrylamide-acrylate copolymer cross-linked product in a mass ratio of (0.34-0.37):

1.

6. The method for preparing a high-fluidity cement-based material anti-bleeding agent according to any one of claims 1 to 4, characterized in that: The raw materials are weighed and mixed evenly to obtain the high-fluidity cement-based material anti-seepage agent.

7. The method for using the anti-bleeding agent for high-fluidity cement-based materials according to any one of claims 1 to 4, characterized in that: The following steps are involved: The water seepage rate of the cement-based material is detected, and then the anti-water seepage agent is added to the cement-based material while stirring according to the severity of the water seepage, until the degree of water seepage is reduced to within the range required by the construction.

8. A method for detecting a high-fluidity cement-based material anti-bleeding agent according to any one of claims 1 to 4, characterized in that: Corresponding to the reduction value of water bleeding rate, the value is tested by the following method: ΔB = 4% - Bc; Where: ΔB is the reduction value of water seepage rate; 4% is the excess water dosage, which makes the water seepage rate reach 4%; Bc is the water seepage rate of concrete after overdosing with water to make the water seepage rate reach 4% and then adding anti-seepage agent.

9. The method for detecting a high-fluidity cement-based material anti-bleeding agent according to claim 1, characterized in that: In the Bc, the amount of the anti-water seepage agent added is 80g / m 3 .

10. The method for detecting a high-fluidity cement-based material anti-bleeding agent according to claim 1, characterized in that: The ΔB is >3.5%.

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