A long operable time plugging material and its use method

Abstract

The application relates to the technical field of building plugging materials, and particularly provides a long-operable-time plugging material, which is prepared from the following raw materials in terms of total weight: 0.02-3% of a retarder, 0.005-2% of a calcium salt, 0.001-1% of a cellulose ether and cement supplementing to 100%. By optimizing the types of the retarder, the calcium salt and the cellulose ether and by stipulating the relative amounts of the retarder, the calcium salt and the cellulose ether, the quick-setting type plugging material has a relatively long retarding time, and the anti-bending performance, the anti-permeation performance, the bonding performance, the heat resistance and the freeze-thaw cycle resistance of the material after solidification are effectively improved.

Description

Technical Field

[0001] This invention relates to the field of building sealing materials technology, C04B16 / 02, and particularly to a leak-sealing material with a long working time and its application method. Background Technology

[0002] In the construction industry, structural cracks and pores caused by various factors are frequently encountered during the construction of underground structures, roofs, tunnels, and bridges. This necessitates the use of high-performance reinforcement materials to seal and repair these cracks and defects, ensuring the structure's safety, durability, and waterproofing. However, currently available sealing materials, besides having unsatisfactory sealing performance, flexural strength, or temperature resistance, also prioritize rapid hardening, resulting in short working times and difficulties in construction, thus limiting their application. Therefore, developing materials with superior sealing performance has significant market value.

[0003] Chinese patent CN114477931A discloses a foamed aluminate cement-based waterproof and leak-stopping material for thermal pipelines and its preparation. The sealing material of this patent includes: 57-82 parts of clay clinker, 25-45 parts of bauxite clinker, 10-15 parts of cementitious material, 5-10 parts of silica fume, 0.5-2.5 parts of water-reducing agent, 0.5-1.5 parts of calcium peroxide, 0.3-0.65 parts of foam stabilizer, 0.2-0.4 parts of retarder, and 20-35 parts of water. Among them, aluminate cement and silica fume enhance the early strength, while clay clinker and bauxite clinker enhance the bonding performance of the material. Although the material has good impermeability and sealing performance, its curing time is very fast, which is not conducive to building construction. Chinese patent CN113651590B discloses a building sealing composite material and its application method. It uses a water-based epoxy curing agent to enhance the material's adhesion and durability in humid environments, and uses rubber particles to replace traditional sand to provide elasticity and reduce the material's curing shrinkage. However, the material's flexural strength is insufficient and its heat resistance needs to be improved. Summary of the Invention

[0004] To address the aforementioned technical problems, the present invention first provides a leak-sealing material with a long working time; by total weight, the raw materials of the leak-sealing material include: 0.02-3% retarder, 0.005-2% calcium salt, 0.001-1% cellulose ether, and cement to make up to 100%.

[0005] Furthermore, by total weight, the raw materials of the sealing material include: 0.02-1% retarder, 0.005-0.8% calcium salt, 0.001-0.5% cellulose ether, and cement to make up to 100%.

[0006] Furthermore, the cement includes, but is not limited to, at least one of silicate cement, ordinary cement, slag cement, pozzolanic cement, fly ash cement, aluminate cement, and sulfoaluminate cement.

[0007] Furthermore, the cement includes at least one of silicate cement, pozzolanic cement, aluminate cement, and sulfoaluminate cement.

[0008] Furthermore, the cement includes at least one of aluminate cement and sulfoaluminate cement.

[0009] Preferably, the cement includes aluminate cement and sulfoaluminate cement.

[0010] Furthermore, the setting time of the aluminate cement is 10-90s, preferably 20-65s.

[0011] Furthermore, the setting time of the sulfoaluminate cement is 10-15 min.

[0012] Furthermore, in the cement, the weight ratio of aluminate cement to sulfoaluminate cement is 8-20:33-60, preferably 10-15:50-60.

[0013] In a preferred embodiment, the weight ratio of the aluminate cement to the sulfoaluminate cement is 13-15:54-57.

[0014] Furthermore, the strength grade of the aluminate cement is at least one of grade 42.5 and grade 52.5, and the test standard for the strength grade is GB20472-2006.

[0015] Furthermore, the retarder includes at least one of organic acids, inorganic acids, inorganic salts, and organic salts.

[0016] Furthermore, the organic acids include, but are not limited to, at least one of formic acid, malonic acid, butyric acid, valeric acid, tartaric acid, citric acid, gluconic acid, fumaric acid, succinic acid, glycolic acid, and hydroxysuccinic acid.

[0017] Furthermore, the inorganic acids include, but are not limited to, at least one of boric acid and phosphoric acid.

[0018] Furthermore, the inorganic salts include, but are not limited to, at least one of calcium sulfate, calcium sulfite, ferrous sulfate, disodium phosphate, trisodium phosphate, tetrasodium phosphate, sodium hexametaphosphate, sodium pyrophosphate, sodium aluminate, and aluminum sulfate.

[0019] Furthermore, the organic salts include, but are not limited to, at least one of tartrates, lignin sulfonates, hydroxycarboxylate salts, and alkylphosphonates.

[0020] Preferably, the retarder comprises organic acids.

[0021] More preferably, the organic acid includes hydroxysuccinic acid. Hydroxysuccinic acid belongs to the hydroxycarboxylic acid class of water-reducing agents, and its molecule has three strongly polar groups: one hydroxyl group and two carboxyl groups. These strongly polar groups associate with water molecules through hydrogen bonds, forming a water film on the surface of cement hydration particles. This not only improves the flow properties of the material but also hinders the depth of hydration. In addition, its hydroxyl group can also react with free CaO in cement and other materials. 2+ The formation of unstable complexes controls Ca in the early stages of hydration. 2+ The concentration and Ca(OH)2 precipitation rate are controlled to comprehensively delay the initial setting time of the material. Compared with other retarders, hydroxysuccinic acid has a simple molecular structure, and its chain length and polarity are more suitable for the needs of this system. It can not only effectively extend the initial setting time of the sealing material, but also has less impact on the product strength.

[0022] Furthermore, the calcium salt includes, but is not limited to, at least one of calcium formate, calcium acetate, calcium chloride, calcium nitrate, and calcium dihydrogen phosphate.

[0023] Furthermore, the calcium salt includes at least one of calcium formate and calcium acetate.

[0024] Preferably, the calcium salt comprises calcium formate.

[0025] Furthermore, the cellulose ether includes, but is not limited to, at least one of methylcellulose, ethylcellulose, methylethylcellulose, hydroxymethylcellulose, hydroxyethylcellulose, hydroxypropylcellulose, carboxymethylcellulose, carboxyethylcellulose, carboxymethylethylcellulose, hydroxypropylmethylcellulose, and carboxymethylhydroxyethylcellulose.

[0026] Furthermore, the cellulose ether includes at least one of carboxymethyl ethyl cellulose, hydroxypropyl methyl cellulose, and carboxymethyl hydroxyethyl cellulose.

[0027] Preferably, the cellulose ether comprises hydroxypropyl methylcellulose.

[0028] Preferably, the weight ratio of hydroxysuccinic acid, calcium formate, and hydroxypropyl methylcellulose is 3-10:1-5:1-3.

[0029] This application uses hydroxysuccinic acid to retard the setting of the material, mainly because hydroxysuccinic acid has a suitable degree of retardation and has a relatively small impact on the mechanical strength of the material. However, when using calcium formate to improve the early strength and impermeability of the material, it always has an adverse effect on the initial setting time. The reason for this is that the COO in calcium formate... -Ions can penetrate the hydration layers of C3S and C2S, accelerating the precipitation of Ca(OH)2 and the decomposition of calcium silicate, and further binding silicon atoms with OH through chemical action. - The reaction crosslinks adjacent silicate groups, promoting the formation of CSH gel and increasing the hardening strength of cement mortar, which is to say, promoting hydration. This is the opposite of the effect of hydroxysuccinic acid (HSA). Furthermore, its addition increases the calcium ion content in the material, which can consume some of the HSA. Hydroxypropyl methylcellulose (HMCMC) is used to improve the fluidity, smoothness, and uniformity of mortar. However, when the weight ratio of HSA, calcium formate, and HMCMC is specified as 3-10:1-5:1-3, it not only solves the weakening effect of HSA and calcium formate on each other and effectively prolongs the initial setting time of the sealing material, but also improves the material's impermeability, flexural strength, and heat resistance. This may be because HMCMC reduces the reaction rate of C3S in cement during the acceleration period and prolongs the induction period of the C3A-CaSO4 system, thereby delaying the hydration reaction of the system and facilitating the effect of HSA. Its suitable chain length and polarity allow it to participate in the mechanical network structure of cement, contributing to COO2. - The penetration enhances the impermeability, and the cross-linking effect imparted to the network structure also improves the material's resistance to shrinkage, flexural strength, and heat resistance.

[0030] Furthermore, the weight ratio of the hydroxysuccinic acid, calcium formate, and hydroxypropyl methylcellulose is 4-8:2-4:1-3.

[0031] In a preferred embodiment, the weight ratio of hydroxysuccinic acid, calcium formate, and hydroxypropyl methylcellulose is 6:3:2.

[0032] Furthermore, the raw materials for the sealing material also include 10-40% black sand. Black sand has a smooth surface, which can improve the smoothness of construction, and its mechanical properties can provide early strength to the material. However, if too much black sand is added, it will cause a decrease in cement adhesion and mechanical strength. In addition, its particle size is specified to be 70-140 mesh. By utilizing its particle distribution in cement, it can effectively reduce the stress received by cement materials with strong cross-linking effects, avoid crack propagation, and improve the flexural strength and freeze-thaw resistance of the material. When its particle size is too large or too small, it will lead to a decrease in the material's impermeability, bonding strength, and flexural strength.

[0033] Furthermore, the amount of black sand used accounts for 20-35% of the total weight of the sealing material raw materials, preferably 25-35%.

[0034] Furthermore, the average particle size of the black sand is 50-300 mesh, preferably 50-200 mesh, and more preferably 70-140 mesh.

[0035] Furthermore, the method for preparing the sealing material is as follows: simply mix the raw materials evenly.

[0036] Preferably, the method for preparing the sealing material is as follows: first, mix cement and black sand evenly, then add cellulose ether, calcium salt and retarder and mix evenly.

[0037] Furthermore, the method of using the sealing material is as follows: simply mix the sealing material with water.

[0038] Furthermore, the amount of water used accounts for 15-45% of the weight of the sealing material, preferably 20-40%, and more preferably 25-35%.

[0039] Beneficial effects

[0040] 1. This application uses cement of different specifications in compounding, resulting in good material homogeneity, high early strength, stronger frost resistance, wear resistance, and impermeability, and initially extending the workable time;

[0041] 2. This application specifies that the retarder is hydroxysuccinic acid, which can not only effectively extend the initial setting time of the quick-setting sealing material, but also reduce the impact of the retarder on the mechanical strength of the sealing material.

[0042] 3. This application uses cellulose ether in combination and specifies the weight ratio of the hydroxysuccinic acid, calcium formate and hydroxypropyl methylcellulose, which not only improves the initial retarding effect of the sealing material, but also improves its impermeability, flexural strength and heat resistance.

[0043] 4. This application incorporates a certain amount of black sand, and specifies that the average particle size of the black sand is 70-140 mesh, which not only improves the smoothness of the material during construction, but also improves its flexural strength and freeze-thaw resistance.

[0044] 5. The sealing material of this application is a quick-setting material, but it has a relatively long initial setting time on the basis of quick drying, which can effectively improve the workability and construction convenience of quick-setting materials, and does not affect the final setting time and strength of the material. It can be used for crack sealing in the construction industry. Detailed Implementation

[0045] Example

[0046] Example 1

[0047] This embodiment provides a leak-sealing material with a long working time; the raw materials of the leak-sealing material, by total weight, include:

[0048] The composition includes 14.15% aluminate cement, 55.77% sulfoaluminate cement, 0.06% retarder, 0.03% calcium salt, 0.02% cellulose ether, and 29.97% black sand.

[0049] The aluminate cement has a strength grade of 42.5 and a setting time of 20-65 seconds. It was purchased from Anda Special Cement Co., Ltd.

[0050] The sulfoaluminate cement had a setting time of 10-15 minutes and was purchased from Henan Yong'an Bridge and Tunnel Building Materials Co., Ltd.

[0051] The retarder is hydroxysuccinic acid.

[0052] The calcium salt is calcium formate.

[0053] The cellulose ether is hydroxypropyl methylcellulose, purchased from Northern Tianpu Cellulose Co., Ltd.

[0054] The black sand has an average particle size of 100 mesh and was purchased from Jiangxi Jinjiuqian New Material Co., Ltd.

[0055] The method for preparing the sealing material is as follows: first, mix cement and black sand evenly, then add cellulose ether, calcium salt and retarder and mix evenly.

[0056] Example 2

[0057] This embodiment provides a leak-sealing material with a long working time; the raw materials of the leak-sealing material, by total weight, include:

[0058] The composition includes 10.5% aluminate cement, 60% sulfoaluminate cement, 0.8% retarder, 0.4% calcium salt, 0.3% cellulose ether, and 28% black sand.

[0059] The aluminate cement has a strength grade of 42.5 and a setting time of 20-65 seconds. It was purchased from Anda Special Cement Co., Ltd.

[0060] The sulfoaluminate cement had a setting time of 10-15 minutes and was purchased from Henan Yong'an Bridge and Tunnel Building Materials Co., Ltd.

[0061] The retarder is hydroxysuccinic acid.

[0062] The calcium salt is calcium formate.

[0063] The cellulose ether is hydroxypropyl methylcellulose, purchased from Northern Tianpu Cellulose Co., Ltd.

[0064] The black sand has an average particle size of 140 mesh and was purchased from Jiangxi Jinjiuqian New Material Co., Ltd.

[0065] The method for preparing the sealing material is as follows: first, mix cement and black sand evenly, then add cellulose ether, calcium salt and retarder and mix evenly.

[0066] Example 3

[0067] This embodiment provides a leak-sealing material with a long working time; the raw materials of the leak-sealing material, by total weight, include:

[0068] The composition includes 15% aluminate cement, 49.93% sulfoaluminate cement, 0.04% retarder, 0.02% calcium salt, 0.01% cellulose ether, and 35% black sand.

[0069] The aluminate cement has a strength grade of 42.5 and a setting time of 20-65 seconds. It was purchased from Anda Special Cement Co., Ltd.

[0070] The sulfoaluminate cement had a setting time of 10-15 minutes and was purchased from Henan Yong'an Bridge and Tunnel Building Materials Co., Ltd.

[0071] The retarder is hydroxysuccinic acid.

[0072] The calcium salt is calcium formate.

[0073] The cellulose ether is hydroxypropyl methylcellulose, purchased from Northern Tianpu Cellulose Co., Ltd.

[0074] The black sand has an average particle size of 70 mesh and was purchased from Jiangxi Jinjiuqian New Material Co., Ltd.

[0075] The method for preparing the sealing material is as follows: first, mix cement and black sand evenly, then add cellulose ether, calcium salt and retarder and mix evenly.

[0076] Comparative Example 1

[0077] The method is basically the same as in Example 1, except that, by total weight, the raw materials of the sealing material include:

[0078] The composition includes 69.92% sulfoaluminate cement, 0.06% retarder, 0.03% calcium salt, 0.02% cellulose ether, and 29.97% black sand.

[0079] Comparative Example 2

[0080] The method is basically the same as in Example 1, except that, by total weight, the raw materials of the sealing material include:

[0081] Aluminate cement 25.0%, sulfoaluminate cement 44.92%, retarder 0.06%, calcium salt 0.03%, cellulose ether 0.02%, black sand 29.97%.

[0082] Comparative Example 3

[0083] It is basically the same as Example 1, except that the retarder is citric acid.

[0084] Comparative Example 4

[0085] It is basically the same as Example 1, except that the calcium salt is calcium chloride.

[0086] Comparative Example 5

[0087] The method is basically the same as in Example 1, except that, by total weight, the raw materials of the sealing material include:

[0088] The composition includes 14.15% aluminate cement, 55.77% sulfoaluminate cement, 0.06% retarder, 0.05% calcium salt, 0.005% cellulose ether, and 29.97% black sand.

[0089] Comparative Example 6

[0090] It is basically the same as Example 1, except that the particle size of the black sand is 400 mesh.

[0091] Performance testing methods:

[0092] The materials and water (30% of the weight of the sealing material) of the examples and comparative examples were mixed and stirred to prepare the specified test samples. The setting time, compressive strength, flexural strength, impermeability pressure, bond strength, heat resistance and freeze-thaw cycle resistance of the above examples and comparative examples were tested according to GB 23440-2009 standard. The test results are shown in Table 1.

[0093] Table 1

[0094]

[0095]

Claims

1. A leak-sealing material with a long working time, characterized in that, The raw materials of the sealing material, by total weight, include: 0.02-3% retarder, 0.005-2% calcium salt, 0.001-1% cellulose ether, and cement to make up to 100%; The cement includes aluminate cement and sulfoaluminate cement; In the cement, the weight ratio of aluminate cement to sulfoaluminate cement is 8-20:33-60; The retarder is hydroxysuccinic acid; The calcium salt is calcium formate; The cellulose ether is hydroxypropyl methylcellulose; The weight ratio of hydroxysuccinic acid, calcium formate, and hydroxypropyl methylcellulose is 3-10:1-5:1-3; The raw materials for the sealing material also include 10-40% black sand, with an average particle size of 50-300 mesh.

2. The sealing material according to claim 1, characterized in that, The weight ratio of hydroxysuccinic acid, calcium formate, and hydroxypropyl methylcellulose is 4-8:2-4:1-3.

3. A method of using the sealing material according to claim 1 or 2, characterized in that, The method of use is as follows: simply mix the sealant with water; the amount of water used should be 15-45% of the weight of the sealant.

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