High-toughness low-shrinkage low-cost repair material for inspection well spray coating and preparation method of high-toughness low-shrinkage low-cost repair material

Abstract

The invention discloses a high-toughness low-shrinkage low-cost repair material for inspection well spraying and a preparation method thereof. The repair material is prepared from the following raw materials in parts by weight: 25-35 parts of a ternary compound cementing material, 50-80 parts of a double-silicon-based composite functional aggregate, 0.1-1 part of an additive, 1-3 parts of a macro-micro composite reinforced repair base material and 6-15 parts of water. The preparation method of the repair material comprises the following steps: uniformly mixing the ternary compound cementing material, the double-silicon-based composite functional aggregate and the macro-micro composite reinforced repair base material, then adding water, and continuously stirring uniformly. Macro-micro composite reinforced repair base materials are introduced, structural and functional reinforcement can be achieved at the same time through multi-scale reinforcement (millimeter + micron), the advantages of high cohesiveness, low shrinkage, extreme environment resistance and low cost are achieved, industrial solid waste is effectively utilized in the material preparation process, the environmental protection bottleneck of existing epoxy resin type repair materials is overcome, and the method is suitable for large-scale popularization and application. And the technical breakthrough of solid waste resource utilization can be realized.

Description

Technical Field

[0001] The present invention belongs to the technical field of road engineering materials, and in particular relates to a high-strength, low-toughness, low-cost inspection well spray repair material and a preparation method thereof. Background Art

[0002] In my country's urban drainage facilities, an inspection well is generally set up every 30 to 50 meters along the drainage pipe. The number is huge. However, with the increase of service life, the inspection wells are prone to leakage, corrosion, surface layer shedding, cracking, settlement around the well, structural damage and other phenomena due to cavitation, vehicle load, soil damage and other reasons. Therefore, the repair of inspection wells is particularly important.

[0003] However, traditional excavation repair technology or pipe replacement causes more interference to the surrounding environment, takes a long time to construct, has high construction risks, and has high costs for restoring the road surface and greening. There is a certain contradiction between efficiency and safety. Therefore, trenchless repair technology has become a development trend.

[0004] Currently, spray repair has become a widely used technology in trenchless repair due to its characteristics of being less susceptible to structural restrictions and being more flexible. However, a summary of existing spray repair materials still has the following shortcomings:

[0005] 1) Commonly used silicate-based repair materials have problems such as low early strength, long construction time, and low 28-day strength. Some repair materials using sulphoaluminate cement, although with high early strength, often suffer from a significant decrease in structural strength after a period of time.

[0006] 2) It is difficult for the material to achieve simultaneous structural and functional reinforcement, and it is difficult to adapt to the complex and changing actual application environment. It is manifested as low adhesion, poor shrinkage, easy to fall off and crack, and difficult to maintain good performance in low and high temperature environments;

[0007] 3) Although currently popular epoxy resin repair materials have high strength and high viscosity, they have limited high temperature resistance, often have a pungent odor before the resin is cured, have a long curing time, and are less environmentally friendly;

[0008] 4) Existing high-performance repair materials are generally sold at high prices, reaching around 2,000 yuan per ton.

[0009] Therefore, a new technology is urgently needed to overcome the defects of existing spraying materials, so as to achieve structural and functional reinforcement, have self-repair functions, enhance environmental protection, reduce carbon emissions and reduce costs to a certain extent. Summary of the Invention

[0010] Based on the above-mentioned existing technology, the present invention provides a high-strength, low-shrinkage, and low-cost inspection well spray repair material and a preparation method thereof. The present invention introduces a macro-micro composite reinforced repair base material, which cooperates with cementitious materials such as sulfoaluminate cement and dual-silicon composite functional aggregates. Through multi-scale reinforcement (millimeter + micron), a small amount of addition can construct a fast-hardening system with high strength and toughness, adhesion, low shrinkage, self-repair and environmental protection functions, and overcomes the difficulties of low adhesion, easy collapse of late strength, high cost, and poor environmental protection of traditional materials, thereby achieving a significant improvement in inspection well repair efficiency, a significant reduction in comprehensive cost, and a technological breakthrough in the resource utilization of solid waste.

[0011] The technical solution adopted to achieve the above-mentioned purpose of the present invention is:

[0012] A high-strength, low-shrinkage, and low-cost inspection well spray repair material is prepared from the following raw materials in parts by weight: 25-35 parts of a ternary composite cementitious material, 50-80 parts of a double-silicon-based composite functional aggregate, 0.1-1 part of an admixture, 1-3 parts of a macro-micro composite reinforced repair base material, and 6-15 parts of water;

[0013] The ternary composite cementitious material is composed of the following components in parts by weight: 1 to 30 parts of sulphoaluminate cement, 2 to 5 parts of silica fume, and 1 to 5 parts of phosphogypsum;

[0014] The double silicon-based composite functional aggregate is prepared by autoclaving and curing the following raw materials in parts by weight: 15 to 20 parts of steel slag, 15 to 20 parts of blast furnace slag, 20 to 30 parts of quartz sand, 10 to 20 parts of quicklime, and 0.1 to 1 part of a gas generating agent;

[0015] The macro-micro composite reinforcement repair base material is composed of the following components in parts by weight: 0.5 to 2 parts of volcanic rock fiber, 0.25 to 1 part of wollastonite whisker, and 0.01 to 0.05 parts of fly ash microbeads.

[0016] Furthermore, the mass fraction of SiO2 in the silicon powder is not less than 95%.

[0017] Furthermore, the preparation method of the double silicon-based composite functional aggregate is as follows:

[0018] 1. Mix steel slag, blast furnace slag, quartz sand, quicklime and gas generating agent evenly, then add 12 to 25 parts by weight of water and stir evenly to obtain a slurry;

[0019] 2. Curing the slurry at room temperature for 4 to 6 hours. After curing, place it in an autoclave and steam cure it at a steam pressure of 1 to 1.5 MPa for 6 to 10 hours to obtain steam curing material.

[0020] 3. Crushing and screening the steamed nutrient to obtain the double silicon-based composite functional aggregate.

[0021] Furthermore, the gas generating agent is H2O2.

[0022] Furthermore, the particle size of the dual silicon-based composite functional aggregate is 8 to 70 meshes.

[0023] Furthermore, the length of the volcanic rock fiber is 4 to 8 mm, the length of the wollastonite whisker is 30 to 80 μm and the diameter is 3 to 5 μm, and the particle size of the fly ash microbeads is 0.1 to 5 μm.

[0024] Furthermore, the admixture is a high-efficiency polycarboxylate water reducer.

[0025] A method for preparing a high-strength, low-toughness, low-cost inspection well spray repair material comprises the following steps:

[0026] The ternary composite cementitious material, the dual silicon-based composite functional aggregate and the macro-micro composite reinforced repair base material are mixed evenly, and then water is added and stirred evenly to obtain the high-strength, low-toughness, low-cost inspection well spray repair material.

[0027] Compared with the prior art, the advantages and beneficial effects of the present invention are:

[0028] 1. The present invention introduces a macro-micro composite reinforced repair base material, combined with a ternary composite cementitious material and a double silicon-based composite functional aggregate. Through multi-scale reinforcement (millimeter + micron), energy dissipation synergy and interface optimization, the repair material has high strength, high toughness and low shrinkage characteristics, constructing a repair system with a bonding strength of ≥3MPa and a shrinkage of ≤0.05%, while simultaneously improving the compressive strength by more than 10MPa. It has both low-temperature and high-temperature curing and adaptability to wet base surfaces, overcoming the technical bottlenecks of general materials such as low bonding strength, high brittleness, high shrinkage, easy falling off and cracking, and late strength collapse of sulphoaluminate cement.

[0029] 2. The present invention introduces a macro-micro composite reinforced repair base material, which works synergistically with the ternary composite cementitious material and the double silicon-based composite functional aggregate to reduce the amount of cement by more than 30% while maintaining the same performance, thereby reducing the overall cost of the repair material by 20% to 30%. At the same time, functional aggregates are prepared from industrial solid waste such as steel slag and slag, realizing resource recycling. The consumption of natural sand and gravel is reduced by at least 0.8 tons per ton of material.

[0030] 3. This invention overcomes the bottlenecks of trenchless repair efficiency and environmental protection of epoxy resin-based repair materials. Compared with epoxy resin and Portland cement-based repair materials, the material's rapid hardening properties shorten the repair time for a single well by 6-10 hours, significantly reducing the impact of road closures on traffic, making it suitable for emergency repairs. Furthermore, the material reduces carbon emissions per ton of repair work by 20%-40%, providing an innovative solution for the green renewal of urban underground infrastructure. Furthermore, this invention completely eliminates the epoxy resin material system, and the curing process of the repair material emits no irritating odor, enhancing environmental protection from both the material source and the process.

[0031] 4. The production process of the repair material of the present invention is simple to operate, has no secondary pollution, is highly feasible, and the spraying thickness is controllable, which can achieve structural and functional reinforcement at the same time to achieve the purpose of repair. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 This is a photo of the on-site repair of the high-strength, low-toughness, low-cost inspection well spray repair material prepared in Example 1. DETAILED DESCRIPTION

[0033] In order to facilitate those skilled in the art to understand and implement the present invention, the present invention is further described in detail below in conjunction with embodiments. It should be understood that the embodiments described herein are only used to illustrate and explain the present invention and are not used to limit the present invention.

[0034] Example 1

[0035] 1. Weigh 17 parts by mass of steel slag and 20 parts by mass of blast furnace slag, weigh 25 parts by mass of quartz sand as a siliceous material, and grind the quartz sand to 100 mesh. Weigh 20 parts by mass of quicklime as a calcium material, weigh 0.4 parts by mass of H2O2 as a gas generating agent, mix the steel slag, blast furnace slag, quartz sand, quicklime and gas generating agent, then add 16 parts by mass of water and stir to obtain a slurry.

[0036] 2. The slurry was transferred to a disc granulator and allowed to stand for 5 hours at room temperature. After the curing, the slurry was placed in an autoclave and steam-cured at a steam pressure of 1.2 MPa for 8 hours to obtain a steam-cured material.

[0037] 3. Crush and screen the steamed nutrient to obtain 8-70 mesh double silicon-based composite functional aggregate.

[0038] 4. A high-strength, low-toughness, low-cost inspection well spray repair material, prepared from the following raw materials in parts by weight: 30 parts of ternary composite cementitious material, including 24 parts of 625 sulphoaluminate cement, 4 parts of silica fume, and 2 parts of phosphogypsum; 60 parts of dual-silicon composite functional aggregate; 0.5 parts of high-efficiency polycarboxylic acid water reducer; 1.5 parts of macro-micro composite reinforced repair base material, including 1 part of volcanic rock fiber (length 6 mm), 0.48 parts of wollastonite whiskers (length 30-40 μm, diameter 3-4 μm), and 0.02 parts of fly ash microbeads; and 13 parts of water.

[0039] The preparation method of the above-mentioned high-strength, low-toughness, low-cost inspection well spray repair material is as follows:

[0040] Mix cement, silica fume, phosphogypsum, bi-silicon-based composite functional aggregate, high-efficiency polycarboxylate water-reducing agent, volcanic rock fiber, wollastonite whiskers and fly ash microbeads evenly with a cement mortar mixer, then add water, stir slowly for 3 to 5 minutes (140 r / min), and then stir quickly for 3 to 5 minutes (285 r / min) to form a uniform and lump-free mortar, which is a high-strength, low-shrinkage, and low-cost inspection well spray repair material.

[0041] Example 2

[0042] 1. A double silicon-based composite functional aggregate is prepared from the following raw materials in parts by weight: 20 parts of steel slag, 18 parts of blast furnace slag, 23 parts of quartz sand, 18 parts of quicklime, 0.35 parts of H2O2, and 20 parts of water.

[0043] The preparation method of the above-mentioned dual silicon-based composite functional aggregate is the same as that of Example 1.

[0044] 2. A high-strength, low-toughness, low-cost inspection well spray repair material, prepared from the following raw materials in parts by weight: 25 parts of ternary composite cementitious material, including 21 parts of 625 sulphoaluminate cement, 2 parts of silica fume, and 2 parts of phosphogypsum; 70 parts of dual-silicon composite functional aggregate; 1 part of high-efficiency polycarboxylic acid water reducer; 2 parts of macro-micro composite reinforced repair base material, including 1.3 parts of volcanic rock fiber (length 4mm), 0.65 parts of wollastonite whiskers (length 40-60μm, diameter 3-4μm), and 0.05 parts of fly ash microbeads; and 14 parts of water.

[0045] The preparation method of the above-mentioned high-strength, low-toughness and low-cost inspection well spray repair material is the same as that in Example 1.

[0046] Example 3

[0047] 1. A double silicon-based composite functional aggregate is prepared from the following raw materials in parts by weight: 15 parts of steel slag, 15 parts of blast furnace slag, 20 parts of quartz sand, 15 parts of quicklime, 0.2 parts of H2O2, and 14 parts of water.

[0048] The preparation method of the above-mentioned dual silicon-based composite functional aggregate is the same as that of Example 1.

[0049] 2. A high-strength, low-toughness, low-cost inspection well spray repair material, prepared from the following raw materials in parts by weight: 35 parts of ternary composite cementitious material, including 30 parts of 625 sulphoaluminate cement, 3 parts of silica fume, and 2 parts of phosphogypsum; 55 parts of dual-silicon composite functional aggregate; 0.15 parts of high-efficiency polycarboxylic acid water reducer; 1 part of macro-micro composite reinforced repair base material, including 0.68 parts of volcanic rock fiber (length 8 mm), 0.31 parts of wollastonite whiskers (length 30-40 μm, diameter 4-5 μm), and 0.01 parts of fly ash microbeads; and 12 parts of water.

[0050] The preparation method of the above-mentioned high-strength, low-toughness and low-cost inspection well spray repair material is the same as that in Example 1.

[0051] Comparative Example 1

[0052] A repair material for inspection well spray coating is prepared from the following raw materials in parts by weight: 30 parts of a ternary composite cementitious material, including 24 parts of 625 sulphoaluminate cement, 4 parts of silica fume, and 2 parts of phosphogypsum; 60 parts of a double-silicon-based composite functional aggregate; 0.5 parts of a high-efficiency polycarboxylate water reducer; 1 part of volcanic rock fiber (6 mm in length); 0.02 parts of fly ash microbeads; and 13 parts of water.

[0053] The formula and preparation method of the dual silicon-based composite functional aggregate in this comparative example are the same as those in Example 1.

[0054] The preparation method of the inspection well spray repair material of the comparative example is the same as that of Example 1.

[0055] Comparative Example 2

[0056] A repair material for inspection well spray coating is prepared from the following raw materials in parts by weight: 30 parts of a ternary composite cementitious material, including 24 parts of 625 sulphoaluminate cement, 4 parts of silica fume, and 2 parts of phosphogypsum; 60 parts of a double-silicon-based composite functional aggregate; 0.5 parts of a high-efficiency polycarboxylate water reducer; 0.48 parts of wollastonite whiskers (30-40 μm in length and 3-4 μm in diameter); 0.02 parts of fly ash microbeads; and 13 parts of water.

[0057] The formula and preparation method of the dual silicon-based composite functional aggregate in this comparative example are the same as those in Example 1.

[0058] The preparation method of the inspection well spray repair material in this comparative example is the same as that in Example 1.

[0059] Comparative Example 3

[0060] A repair material for inspection well spray coating is prepared from the following raw materials in parts by weight: 30 parts of a ternary composite cementitious material, including 24 parts of 625 sulphoaluminate cement, 4 parts of silica fume, and 2 parts of phosphogypsum; 60 parts of a double-silicon-based composite functional aggregate; 0.5 parts of a high-efficiency polycarboxylate water reducer; 1 part of volcanic rock fiber (6 mm in length); 0.48 parts of wollastonite whiskers (30-40 μm in length and 3-4 μm in diameter); and 13 parts of water.

[0061] The formula and preparation method of the dual silicon-based composite functional aggregate in this comparative example are the same as those in Example 1.

[0062] The preparation method of the inspection well spray repair material in this comparative example is the same as that in Example 1.

[0063] Comparative Example 4

[0064] A repair material for inspection well spray coating is prepared from the following raw materials in parts by weight: 30 parts of ternary composite cementitious material, including 24 parts of 625 sulphoaluminate cement, 4 parts of silica fume, and 2 parts of phosphogypsum; 60 parts of double silicon-based composite functional aggregate; 0.5 parts of high-efficiency polycarboxylic acid water reducer; and 13 parts of water.

[0065] The formula and preparation method of the dual silicon-based composite functional aggregate in this comparative example are the same as those in Example 1.

[0066] The preparation method of the inspection well spray repair material in this comparative example is the same as that in Example 1.

[0067] Comparative Example 5

[0068] A repair material for inspection well spray coating is prepared from the following raw materials in parts by weight: 30 parts of a ternary composite cementitious material, including 24 parts of 625 sulphoaluminate cement, 4 parts of silica fume, and 2 parts of phosphogypsum; 60 parts of quartz sand with a mesh size of 8 to 70; 0.5 parts of a high-efficiency polycarboxylic acid water reducer; 1.5 parts of a macro-micro composite reinforced repair base material, including 1 part of volcanic rock fiber (6 mm in length), 0.48 parts of wollastonite whiskers (30 to 40 μm in length and 3 to 4 μm in diameter), and 0.02 parts of fly ash microbeads; and 13 parts of water.

[0069] The preparation method of the inspection well spray repair material in this comparative example is the same as that in Example 1.

[0070] Comparative Example 6

[0071] A repair material for inspection well spray coating is prepared from the following raw materials in parts by weight: 30 parts of 625 sulphoaluminate cement; 60 parts of dual-silicon composite functional aggregate; 0.5 parts of high-efficiency polycarboxylate water reducer; 1.5 parts of macro-micro composite reinforced repair base material, including 1 part of volcanic rock fiber (6 mm in length), 0.48 parts of wollastonite whiskers (30-40 μm in length, 3-4 μm in diameter), 0.02 parts of fly ash microbeads; and 13 parts of water.

[0072] The formula and preparation method of the dual silicon-based composite functional aggregate in this comparative example are the same as those in Example 1.

[0073] The preparation method of the inspection well spray repair material in this comparative example is the same as that in Example 1.

[0074] Comparative Example 7

[0075] A repair material for inspection well spray coating is prepared from the following raw materials in parts by weight: 30 parts of 625 sulphoaluminate cement; 60 parts of 8-70 mesh quartz sand; 0.5 parts of high-efficiency polycarboxylate water reducer; and 13 parts of water.

[0076] The preparation method of the inspection well spray repair material in this comparative example is the same as that in Example 1.

[0077] The repair materials prepared in Examples 1 to 3 and Comparative Examples 1 to 7 were cured under standard conditions. After the curing, their mechanical properties, high and low temperature resistance, bonding properties, shrinkage properties and other related properties were tested, and their costs were calculated. The results are shown in Tables 1 and 2 below:

[0078] The properties of the high-strength, low-toughness, low-cost inspection well spray repair materials prepared in Examples 1 to 3 are shown in Table 1 below:

[0079] Table 1

[0080]

[0081] The properties of the repair materials prepared in Example 1 and Comparative Examples 1 to 7 are shown in Table 2 below:

[0082] Table 2

[0083]

[0084] Note: The anti-seepage pressure is 1.5 MPa because the maximum anti-seepage pressure of the laboratory testing equipment can only reach 1.5 MPa.

[0085] It can be seen from the above table that compared with traditional repair materials, the cost of the repair materials of this application is significantly reduced, while other properties are significantly improved, especially the shrinkage performance and high and low temperature resistance. The high and low temperature resistance ensures that the material will not burst or frost under extreme temperatures, and the ultra-low shrinkage rate reduces the hollowing and cracking of the material, effectively reducing the full-cycle maintenance cost.

[0086] The repair material of this application has a long service life and good durability in actual application. At the same time, the material meets the performance requirements of cement-based materials for structural repair in the "Construction and Acceptance Regulations for Non-excavation Repair Projects of Urban Drainage Pipelines".

[0087] Taking the high-strength, low-toughness, low-cost inspection well spray repair material prepared in Example 1 as an example, a pipeline spray repair experiment was carried out, and spray construction was carried out with a spray thickness of 10 mm. The construction process was simple, the raw materials were non-irritating, and the environmental protection was strong. The construction results were as follows: Figure 1 As shown. Figure 1 It can be seen that the high-strength, low-toughness, low-cost inspection well spray repair material of the present invention has good wall adhesion.

Claims

1. A high-strength, low-cost inspection well spray repair material, characterized by The invention is prepared from the following raw materials in parts by weight: 25 to 35 parts of ternary composite cementitious material, 50 to 80 parts of double silicon-based composite functional aggregate, 0.1 to 1 part of admixture, 1 to 3 parts of macro-micro composite reinforcement repair base material, and 6 to 15 parts of water; The ternary composite cementitious material is composed of the following components in parts by weight: 1 to 30 parts of sulphoaluminate cement, 2 to 5 parts of silica fume, and 1 to 5 parts of phosphogypsum; The double silicon-based composite functional aggregate is prepared by autoclaving and curing the following raw materials in parts by weight: 15 to 20 parts of steel slag, 15 to 20 parts of blast furnace slag, 20 to 30 parts of quartz sand, 10 to 20 parts of quicklime, and 0.1 to 1 part of a gas generating agent; The macro-micro composite reinforcement repair base material is composed of the following components in parts by weight: 0.5 to 2 parts of volcanic rock fiber, 0.25 to 1 part of wollastonite whisker, and 0.01 to 0.05 parts of fly ash microbeads.

2. The high-strength, low-cost, and low-toughness inspection well spray repair material according to claim 1 is characterized by: The mass fraction of SiO2 in the silicon powder is not less than 95%.

3. The high-strength, low-cost, and low-toughness inspection well spray repair material according to claim 1 is characterized in that The preparation method of the double silicon-based composite functional aggregate is as follows: S1. Mix steel slag, blast furnace slag, quartz sand, quicklime and gas generating agent, then add 12 to 25 parts by weight of water and stir to obtain a slurry; S2. Curing the slurry at room temperature for 4 to 6 hours. After curing, place the slurry in an autoclave and steam cure it at a steam pressure of 1 to 1.5 MPa for 6 to 10 hours to obtain a steam curing material. S3. Crushing and screening the steamed nutrient to obtain the dual silicon-based composite functional aggregate.

4. The high-strength, low-toughness, low-cost inspection well spray repair material according to claim 1 is characterized by: The gas generating agent is H2O2.

5. The high-strength, low-toughness, low-cost inspection well spray repair material according to claim 1 is characterized by: The particle size of the double silicon-based composite functional aggregate is 8 to 70 meshes.

6. The high-strength, low-cost, and low-toughness inspection well spray repair material according to claim 1 is characterized by: The length of the volcanic rock fiber is 4-8 mm, the length of the wollastonite whisker is 30-80 μm and the diameter is 3-5 μm, and the particle size of the fly ash microbeads is 0.1-5 μm.

7. The high-strength, low-cost, and low-toughness inspection well spray repair material according to claim 1 is characterized by: The admixture is a high-efficiency polycarboxylate water reducer.

8. A method for preparing a high-strength, low-cost, and low-toughness inspection well spray repair material according to any one of claims 1 to 7, characterized in that The steps include: The ternary composite cementitious material, the dual silicon-based composite functional aggregate and the macro-micro composite reinforced repair base material are mixed evenly, and then water is added and stirred evenly to obtain the high-strength, low-toughness, low-cost inspection well spray repair material.

Images