Quick-setting early-strength pavement patching material as well as production device, production method and application thereof

Abstract

The invention discloses a quick-setting early-strength pavement patching material as well as a production device, a production method and application thereof, and belongs to the technical field of pavement patching materials. The rapid-hardening early-strength pavement patching material provided by the invention is prepared from the following raw materials in parts by weight: 790 to 900 parts of rapid-hardening sulphoaluminate cement, 140 to 210 parts of fly ash, 200 to 300 parts of blast furnace slag powder, 30 to 80 parts of carbide slag, 30 to 80 parts of phosphogypsum, 10 to 30 parts of metakaolin, 4 to 6 parts of polyvinyl alcohol, 20 to 30 parts of silane coupling agent, 2 to 6 parts of vinyl acetate-ethylene copolymer emulsion, 2 to 6 parts of propylene glycol and 8 to 14 parts of sodium metaaluminate. 10-15 parts of a water reducing agent, 0.5-1 part of a defoaming agent and 580-620 parts of water. The quick-setting early-strength pavement patching material provided by the invention has good permeation resistance, freeze-thaw resistance and construction performance and relatively high bonding strength, and is low in cost and relatively high in solid waste utilization rate.

Description

Technical Field

[0001] The invention relates to the technical field of pavement repair materials, and in particular to a quick-setting early-strength pavement repair material and a production device, a production method and an application thereof. Background Art

[0002] The information disclosed in the background of the invention is only intended to enhance the understanding of the overall background of the invention and should not be necessarily regarded as an acknowledgment or any form of suggestion that the information constitutes the prior art already known to a person skilled in the art.

[0003] At present, the repair materials for cement pavement defects are mainly divided into two categories: organic repair materials and inorganic repair materials. Organic repair materials mainly use organic polymers as gelling materials. The gelling materials and a certain proportion of inorganic admixtures (acting as a skeleton) and additives are added to a reactor in a specific order, and stirred and reacted for a period of time under specific temperature and pressure conditions to obtain repair materials. However, organic repair materials are expensive, the construction process is complicated and the cycle is long, making it difficult to achieve rapid repair of defects; their raw materials and construction costs are high, and their durability is poor, making it difficult to achieve long-term and stable repair effects.

[0004] Inorganic repair materials usually use silicate cement or sulphoaluminate cement as the main cementing component. The preparation process usually includes uniformly mixing the cementing material with additives, then adding water and stirring into a slurry for use. Portland cement is widely used in repair materials due to its low cost and high output. However, the early strength growth of this material is slow, which reduces the repair efficiency and causes adverse effects such as long traffic closure time in road repair.

[0005] Sulphoaluminate cement has the advantages of short setting time, rapid early strength development, and strong corrosion resistance. When used as a road repair material, it can shorten the traffic closure time. However, due to its high raw material cost and the shrinkage of later strength, it is difficult to promote it on a large scale. In addition, the adhesion between conventional sulphoaluminate cement and large-volume ordinary silicate cement matrix is ​​poor, and its impermeability is poor, and it is easy to be eroded when exposed to water. In winter construction, the existing sulphoaluminate cement has a long setting time in a freeze-thaw environment, and the bonding strength is low. The freeze-thaw phenomenon of water infiltrating the interface accelerates the erosion of the repair material, and the application effect in the actual environment is poor.

[0006] Therefore, how to provide a fast-setting sulphoaluminate cement-based pavement rapid repair material with low cost, high early and late strength, high bonding strength with the substrate, good freeze-thaw resistance and impermeability is an urgent problem to be solved. Summary of the invention

[0007] In view of this, the present invention provides a quick-setting and early-strength pavement repair material and a production device, a production method and an application thereof. The present invention uses sulphoaluminate cement as the main cementitious material, and improves the early and late strength of the material while reducing the cost by adding solid waste-based materials. The pavement repair material provided by the present invention has high bonding strength with the substrate, and has good freeze-thaw resistance and anti-permeability properties.

[0008] In a first aspect, the present invention provides a quick-setting early-strength pavement repair material, which is made of raw materials including the following components in parts by weight:

[0009] 790-900 parts of rapid-hardening sulphoaluminate cement, 140-210 parts of fly ash, 200-300 parts of blast furnace slag powder, 30-80 parts of carbide slag, 30-80 parts of phosphogypsum, 10-30 parts of metakaolin, 4-6 parts of polyvinyl alcohol, 20-30 parts of silane coupling agent, 2-6 parts of vinyl acetate-ethylene copolymer emulsion, 2-6 parts of propylene glycol, 8-14 parts of sodium aluminate, 10-15 parts of water reducer, 0.5-1 part of defoamer and 580-620 parts of water.

[0010] In a second aspect, the present invention provides a production device based on the above-mentioned rapid-setting early-strength pavement repair material, comprising a powder feeding device, a powder mixer and a solid-liquid mixing device, wherein the solid-liquid mixing device is located below one side of the powder mixer, and the powder mixer is connected to the solid-liquid mixing device through a conveying channel;

[0011] The powder mixer is provided with a blower blade, a spiral stirring blade and a stirring bearing; the blower blade is arranged on a side away from the conveying channel and is connected to the blower drive motor; the stirring bearing is connected to the stirring drive motor, and the spiral stirring blade is arranged on the stirring bearing;

[0012] The solid-liquid mixing device comprises a solid-liquid mixing and stirring pot, a pot cover and a stirring paddle, and a liquid injection hole is arranged on the pot cover.

[0013] In a third aspect, the present invention provides a method for producing the above-mentioned rapid-setting early-strength pavement repair material, based on the above-mentioned production device, comprising the following steps:

[0014] Rapid hardening sulphoaluminate cement, fly ash, blast furnace slag powder, carbide slag, phosphogypsum, metakaolin, water reducing agent, defoaming agent and sodium metaaluminate are added into the powder mixer through the powder feeding device in proportion, the stirring drive motor is turned on to mix the dry materials, and then the blast drive motor is turned on to transport the dry materials to the transport channel and enter the solid-liquid mixing and stirring pot through the transport channel;

[0015] The polyvinyl alcohol and the silane coupling agent are fully mixed in advance and heated for reaction to obtain a polyvinyl alcohol cross-linking reaction liquid; water is injected into the solid-liquid mixing stirring pot through the injection hole, and then the stirring paddle is turned on for preliminary mixing; then the polyvinyl alcohol cross-linking reaction liquid, vinyl acetate-ethylene copolymer emulsion and propylene glycol are injected into the solid-liquid mixing stirring pot through the injection hole, and the stirring paddle is turned on for formal mixing to obtain a quick-setting and early-strength pavement repair material.

[0016] In a fourth aspect, the present invention provides an application of the above-mentioned quick-setting and early-strength pavement repair material or the quick-setting and early-strength pavement repair material produced by the above-mentioned production method in repairing pavement cracks, and the application method is: injecting the quick-setting and early-strength pavement repair material into the pavement cracks, without special maintenance, and opening to traffic after 5 hours.

[0017] Compared with the prior art, the present invention has achieved the following beneficial effects:

[0018] (1) The quick-setting and early-strength pavement repair material provided by the present invention uses quick-hardening sulphoaluminate cement as the main cementitious material. With the auxiliary stimulation of fly ash, blast furnace slag powder, carbide slag and phosphogypsum and other industrial wastes, it can not only effectively reduce costs but also improve the utilization rate of solid wastes. At the same time, under the joint action of materials such as metakaolin, polyvinyl alcohol, silane coupling agent, vinyl acetate-ethylene copolymer emulsion, propylene glycol, sodium metaaluminate, etc., the quick-setting and early-strength pavement repair material provided by the present invention has good anti-permeability, high early strength and late strength, fast setting rate, high bonding strength, good freeze-thaw resistance and construction performance; the fluidity is more than 240 mm, the initial setting time is 10 to 20 minutes, and the final setting time is 40 to 60 minutes. Even in a low temperature environment of 0°C, the final setting time is still short, which is 55 to 75 minutes; the permeability coefficient after hardening is less than 3.5×10 -12 m / s, 5h compressive strength shall not be less than 14MPa, 5h flexural strength shall not be less than 2.5MPa; 1d compressive strength shall not be less than 20.5MPa, 1d flexural strength shall not be less than 5MPa, 1d bonding strength shall not be less than 3MPa; 28d compressive strength shall not be less than 44.5MPa, 28d flexural strength shall not be less than 8.5MPa.

[0019] (2) The present invention designs an integrated production device for the quick-setting and early-strength pavement repair material provided. When the quick-setting and early-strength pavement repair material of the present invention is produced by the device, the solid material and the liquid material can be fully and evenly mixed in a short time (within 10 minutes), thereby eliminating the time for step-by-step stirring and mixing and improving production efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The accompanying drawings forming a part of this invention are used to provide a further understanding of the invention. The schematic embodiments and descriptions thereof of the invention are used to explain the invention and do not unduly limit the invention. Obviously, for those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0021] Figure 1 is a schematic structural diagram of the production device of the rapid-setting and early-strength pavement repair material in Embodiment 1 of the present invention;

[0022] Figure 2 is a schematic internal structure diagram of the powder mixer in Embodiment 1 of the present invention;

[0023] Figure 3 is a schematic internal structure diagram of the solid-liquid mixing device in Embodiment 1 of the present invention;

[0024] Figure 4 is a schematic structural diagram of the ordinary Portland cement crack specimen in the test example of the present invention;

[0025] In the figure, 1. powder mixer; 2. solid-liquid mixing device; 3. powder feeding device; 4. blower fan blade; 5. spiral stirring blade; 6. blower bearing; 7. stirring bearing; 8. first transmission belt; 9. second transmission belt; 10. blower driving motor; 11. first stirring driving motor; 12. conveying channel; 13. solid-liquid mixing and stirring pot; 14. pot lid; 15. stirring paddle; 16. second stirring driving motor; 17. liquid injection hole; 18. spiral switch; 19. liftable base. Detailed implementation manners

[0026] It should be noted that the following detailed descriptions are all exemplary and are intended to provide further explanations of the present invention. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the technical field to which the present invention belongs.

[0027] The present invention provides a rapid-setting and early-strength pavement repair material, which is made of raw materials including the following components by weight:

[0028] 790 - 900 parts of fast-hardening sulphoaluminate cement, 140 - 210 parts of fly ash, 200 - 300 parts of blast furnace slag powder, 30 - 80 parts of carbide slag, 30 - 80 parts of phosphogypsum, 10 - 30 parts of metakaolin, 4 - 6 parts of polyvinyl alcohol, 20 - 30 parts of silane coupling agent, 2 - 6 parts of ethylene-vinyl acetate copolymer emulsion, 2 - 6 parts of propylene glycol, 8 - 14 parts of sodium metaaluminate, 10 - 15 parts of water reducer, 0.5 - 1 part of defoaming agent, 580 - 620 parts of water.

[0029] The present invention uses fast-hardening sulphoaluminate cement as the main cementitious material, which undergoes hydration reaction (CaO·Al 2 O 3 +SO 3 +6H 2 O→CaO·Al 2 O 3 ·SO 3 +6H 2 O), the hydration rate is fast, which ensures the early strength of the repair material; calcium carbide slag is used as a long-term mild activator to assist the alkaline product formed after the hydration of sulphoaluminate cement to stimulate the chemical polymerization reaction of fly ash and blast furnace slag powder to form geopolymer (geopolymer), the chemical reaction (SiO 2 +Al 2 O 3 +4OH - +2H 2 O→2Al(OH) 4- +SiO 3 2- ) is slow and long-lasting, ensuring that the strength of the repair material does not decay to a large extent in the later stage. The introduction of phosphogypsum can reduce costs, appropriately increase the range of initial and final setting time of cement, and improve the controllability of the slurry setting rate. The introduction of sodium aluminate can compensate for the decrease in setting rate and early strength loss caused by the addition of solid waste, and can also react with phosphogypsum to assist in gelling (CaSO 4 ·2H 2 O+NaAlO 2 →Na 2 SO 4 +Ca(OH) 2 +Al 2 O 3 ·2H 2 O). Metakaolin has highly active silica and alumina, and has the potential for volcanic ash reaction. It can effectively disperse sulphoaluminate cement and blast furnace slag powder, reduce powder agglomeration, increase the effective contact area between sulphoaluminate cement and water molecules, and enhance the efficiency of hydration reaction. It can not only improve the appearance and flatness of the product, but also enhance its low temperature resistance and surface wear resistance, reduce water bleeding, and thus improve the later strength of the material.

[0030] The introduction of polyvinyl alcohol (PVA) can reduce stress cracking, reduce the formation of microcracks on the surface of the material, increase the toughness of the product, control the shrinkage rate, and improve the bonding performance between the rapid road repair material and the old cement matrix interface. The introduction of silane coupling agent can not only improve the dispersion of polyvinyl alcohol and the fluidity of the rapid setting and early strength road repair material, but also increase the compatibility and bonding force between the organic material polyvinyl alcohol and the inorganic material cement hydration product and geopolymer. The introduction of vinyl acetate-ethylene copolymer emulsion (VAE) can improve the surface hydrophobicity and water resistance of the material after hardening, and reduce the permeability coefficient of the rapid repair material. The addition of propylene glycol can effectively reduce the freezing point of the mixture and avoid the occurrence of the phenomenon of interruption of hydration reaction caused by freezing of water during winter construction. The present invention finds that under the synergistic effect of polyvinyl alcohol, vinyl acetate-ethylene copolymer emulsion and propylene glycol, the stability of the bonding strength of the rapid setting and early strength road repair material of the present invention under multiple freeze-thaw cycles can be improved, and the development of material cracks under multiple freeze-thaw cycles and the erosion disease under water impact can be alleviated.

[0031] Based on the addition of the above components, the quick-setting early-strength pavement repair material provided by the present invention has good construction performance, a fluidity of more than 240 mm, a fast setting rate, an initial setting time of 10 to 20 minutes, and a final setting time of 40 to 60 minutes. Even in a low temperature environment of 0°C, the final setting time is still relatively short, 55 to 75 minutes. At the same time, it has high early strength and late strength, a 5h compressive strength of not less than 14MPa, a 5h flexural strength of not less than 2.5MPa, a 1d compressive strength of not less than 20.5MPa, a 1d flexural strength of not less than 5MPa, and a 1d bonding strength of not less than 3MPa, a 28d compressive strength of not less than 44.5MPa, and a 28d flexural strength of not less than 8.5MPa, and excellent anti-seepage performance, a permeability coefficient of less than 3.5×10 -12 m / s; and has a higher solid waste utilization rate.

[0032] In the present invention, the rapid hardening sulphoaluminate cement is of grade 42.5, and the present invention does not impose any special restrictions on its source and type. The fly ash of the present invention is grade II fly ash.

[0033] In the present invention, the blast furnace slag powder is preferably granulated blast furnace slag, with a mass coefficient K<1.2 and a sulfide content<3%.

[0034] In the present invention, the particle size of the metakaolin is above 300 meshes, and the mineral content is >90%. The particle size of the polyvinyl alcohol powder is 100-200 meshes, and the polyvinyl alcohol in the present invention is preferably cold water instant polyvinyl alcohol rubber powder, and the present invention does not impose any special restrictions on its source, and commercially available products can be used.

[0035] In the present invention, the silane coupling agent is KH550 or KH570; in one or more embodiments of the present invention, the silane coupling agent is KH550. In the present invention, the solid content of the vinyl acetate-ethylene copolymer emulsion is 50-60%.

[0036] In the present invention, the water reducer is selected from any one of naphthalene-based high-efficiency water reducer, aliphatic high-efficiency water reducer, amino high-efficiency water reducer, and polycarboxylic acid high-efficiency water reducer; in one or more embodiments of the present invention, the water reducer is selected from carboxylic acid high-efficiency water reducer. The defoamer is selected from any one of polyether defoamers, silicone defoamers, or phosphate defoamers. The present invention preferably uses a polyether defoamer, which is used to eliminate bubbles generated during the stirring process of the rapid-setting early-strength pavement repair material and improve the density of the hardened material.

[0037] The present invention also provides a production device based on the above-mentioned rapid-setting early-strength pavement repair material, comprising a powder feeding device, a powder mixer and a solid-liquid mixing device, wherein the solid-liquid mixing device is located below one side of the powder mixer, and the powder mixer is connected to the solid-liquid mixing device through a conveying channel;

[0038] The powder mixer is provided with a blower blade, a spiral stirring blade and a stirring bearing; the blower blade is arranged on a side away from the conveying channel and is connected to the blower drive motor; the stirring bearing is connected to the stirring drive motor, and the spiral stirring blade is arranged on the stirring bearing;

[0039] The solid-liquid mixing device comprises a solid-liquid mixing and stirring pot, a pot cover and a stirring paddle, and a liquid injection hole is arranged on the pot cover.

[0040] In the prior art, the pavement repair material is usually mixed manually in steps, which is time-consuming and labor-intensive. The present invention uses the above-mentioned production device to achieve rapid mixing of the quick-setting and early-strength pavement repair material.

[0041] In the present invention, the blower blades in the powder mixer are arranged on a side away from the conveying channel, and are used to blow the mixed dry materials into the conveying channel. A switch is also arranged at the connection point between the conveying channel and the powder mixer. When the switch is closed, the conveying channel and the powder mixer are in an isolated state, and when the switch is opened, the conveying channel and the powder mixer are in a connected state.

[0042] The present invention also provides a method for producing the above-mentioned quick-setting early-strength pavement repair material, based on the above-mentioned production device, comprising the following steps:

[0043] Rapid hardening sulphoaluminate cement, fly ash, blast furnace slag powder, carbide slag, phosphogypsum, metakaolin, water reducing agent, defoaming agent and sodium metaaluminate are added into the powder mixer through the powder feeding device in proportion, the stirring drive motor is turned on to mix the dry materials, and then the blast drive motor is turned on to transport the dry materials to the transport channel and enter the solid-liquid mixing and stirring pot through the transport channel;

[0044] The polyvinyl alcohol and the silane coupling agent are fully mixed in advance and heated for reaction to obtain a polyvinyl alcohol cross-linking reaction liquid; water is injected into the solid-liquid mixing stirring pot through the injection hole, and then the stirring paddle is turned on for preliminary mixing; then the polyvinyl alcohol cross-linking reaction liquid, vinyl acetate-ethylene copolymer emulsion and propylene glycol are injected into the solid-liquid mixing stirring pot through the injection hole, and the stirring paddle is turned on for formal mixing to obtain a quick-setting and early-strength pavement repair material.

[0045] Since the amount of quick-setting and early-strength pavement repair materials used for pavement repair is usually small, and conventional large-scale mixing devices are difficult to achieve rapid preparation of integrated slurry according to the amount used, and the uniformity of the produced slurry needs to be improved, higher requirements are put forward for the preparation efficiency of batching, mixing and production equipment. The production method of quick-setting and early-strength pavement repair materials provided by the present invention is based on a specific production device, which can make solid materials and liquid materials fully mixed and uniform in a short time (within 10 minutes), eliminating the time of step-by-step stirring and mixing, and greatly improving production efficiency.

[0046] In the present invention, the dry material mixing time is 2 to 5 minutes, and the rotation speed of the dry material mixing is 100 to 200 rpm. After the dry materials are mixed, the present invention keeps the stirring drive motor turned on, and then turns on the blast drive motor. At this time, the blast fan blades rotate to blow the dry mixed material to one side of the conveying channel, so that the dry material enters the solid-liquid mixing and stirring pot. The process lasts for about 2 minutes, and the dry mixed material in the powder mixer can completely enter the solid-liquid mixing and stirring pot, which is fast and does not require manual intervention.

[0047] In the present invention, in the step of fully mixing the polyvinyl alcohol and the silane coupling agent and heating them for reaction, the temperature of the heating reaction is 50 to 70° C., and the time of the heating reaction is 20 to 60 minutes.

[0048] In the present invention, the speed of the preliminary mixing is 200-300 rpm, and the time of the preliminary mixing is 15-30 seconds; the preliminary mixing allows the dry mixed material to be initially dispersed in water. The speed of the formal mixing is 400-600 rpm, and the time of the formal mixing is 30-60 seconds.

[0049] The present invention also provides an application of the above-mentioned quick-setting and early-strength pavement repair material or the quick-setting and early-strength pavement repair material produced by the above-mentioned production method, wherein the application is application in pavement crack repair, and the application method is: injecting the quick-setting and early-strength pavement repair material into the pavement crack, without special maintenance, and opening to traffic after 5 hours.

[0050] In the present invention, the special maintenance-free method mainly includes two aspects. On the one hand, there is no need to take insulation measures, that is, there is no need to use insulation blankets, straw mats or plastic films to cover the repair area; on the other hand, due to the fast condensation time, the present invention does not need to maintain humidity, that is, there is no need to regularly sprinkle water to keep the surface moist.

[0051] The technical solution of the present invention is further described below in conjunction with specific embodiments.

[0052] In the following examples, the fast-hardening sulphoaluminate cement is commercially available Shili brand 42.5 grade cement, the fly ash grade is II grade, the kaolin particle size is 325 mesh, the polyvinyl alcohol powder is 160 mesh cold water instant PVA glue powder, and the vinyl acetate-ethylene copolymer emulsion is EVA emulsion (CW-707) produced by Dalian Company in Taiwan, China, and its solid content is 55±1%.

[0053] Example 1

[0054] This embodiment provides a production device for quick-setting early-strength road repair material, and its structural schematic diagram is as follows: Figure 1 shown.

[0055] The production device comprises a powder feeding device 3, a powder mixer 1 and a solid-liquid mixing device 2, wherein the solid-liquid mixing device 2 is located below one side of the powder mixer 1. The powder feeding device 3 is arranged at the top of the powder mixer 1 away from the solid-liquid mixing device 2, and its structure is funnel-shaped, which is convenient for powder feeding.

[0056] The internal structure schematic diagrams of the powder mixer 1 and the solid-liquid mixer 2 are respectively as shown in Figure 2 and Figure 3 As shown. The powder mixer 1 is connected to the solid-liquid mixing device 2 through the conveying channel 12. A blower blade 4, a spiral stirring blade 5 and a stirring bearing 7 are arranged in the powder mixer 1; the blower blade 4 is arranged on the side away from the conveying channel 12, and is connected to the blower drive motor 10 through the blower bearing 6 and the first transmission belt 8. The stirring bearing 7 is connected to the first stirring drive motor 11 through the second transmission belt 9. The spiral stirring blade 5 is arranged on the stirring bearing 7. The first stirring drive motor 11 and the blower drive motor 10 are arranged on the side close to the blower blade 4.

[0057] The solid-liquid mixing device 2 comprises a solid-liquid mixing stirring pot 13, a pot cover 14 and a stirring paddle 15, and a liquid injection hole 17 is arranged on the pot cover 14. The stirring paddle 15 is connected to a second stirring drive motor 16. The solid-liquid mixing stirring pot 13 is detachably arranged on a liftable base 19, which is used to adjust the height of the solid-liquid mixing stirring pot 13 for easy material removal.

[0058] A spiral switch 18 is provided at a location on the powder mixer 1 that is connected to the conveying channel 12 , for controlling the isolation or connection between the powder mixer 1 and the conveying channel 12 .

[0059] Example 2

[0060] The present embodiment provides a quick-setting and early-strength pavement repair material, the raw materials of which are as follows: 806.4 g of fast-hardening sulphoaluminate cement, 210 g of fly ash, 210 g of blast furnace slag powder, 70 g of carbide slag, 70 g of phosphogypsum, 28 g of metakaolin, 5.6 g of polyvinyl alcohol powder, 28 g of KH550 silane coupling agent, 5.6 g of vinyl acetate-ethylene copolymer emulsion, 4.2 g of propylene glycol, 11.2 g of sodium aluminate, 14 g of water reducer, 0.7 g of defoaming agent, and 592.2 g of water. Among them, the mass of water is the water consumption calculated according to the water-cement ratio of 0.45 minus the mass of KH550 silane coupling agent, vinyl acetate-ethylene copolymer emulsion and propylene glycol; the mass of cementitious material is the total mass of fast-hardening sulphoaluminate cement, fly ash, blast furnace slag powder, carbide slag, phosphogypsum, metakaolin and polyvinyl alcohol powder, which is constant at 1400g; sodium aluminate, water reducer and defoamer are added externally on the basis of cementitious material.

[0061] Rapid hardening sulphoaluminate cement, fly ash, blast furnace slag powder, carbide slag, phosphogypsum, metakaolin, water reducing agent, defoaming agent and sodium metaaluminate are added into the powder mixer 1 through the powder feeding device 3, and the first stirring drive motor 11 is turned on to mix the dry materials, the stirring speed is 150rpm, and the mixing time is 3min. Then the blast drive motor 10 is turned on to transport the dry materials to the conveying channel 12, and enter the solid-liquid mixing and stirring pot 13 through the conveying channel 12.

[0062] The polyvinyl alcohol and KH550 silane coupling agent are fully mixed in advance and cross-linked in a water bath at 60°C for 30 minutes to obtain a polyvinyl alcohol cross-linking reaction liquid; water is injected into the solid-liquid mixing stirring pot 13 through the injection hole 17, and then the stirring paddle 15 is turned on for preliminary mixing at a speed of 250rpm for 20s; then the polyvinyl alcohol cross-linking reaction liquid, vinyl acetate-ethylene copolymer emulsion and propylene glycol are injected into the solid-liquid mixing stirring pot 13 through the injection hole 17, and the stirring paddle 15 is turned on for formal mixing at a speed of 500rpm for 50s to obtain a quick-setting and early-strength pavement repair material.

[0063] Example 3

[0064] The difference between this embodiment and embodiment 2 is that the formula is different.

[0065] The raw materials of the quick-setting and early-strength pavement repair material of this embodiment are as follows: 807.8g of fast-hardening sulphoaluminate cement, 210g of fly ash, 210g of blast furnace slag powder, 70g of carbide slag, 70g of phosphogypsum, 28g of metakaolin, 4.2g of polyvinyl alcohol powder, 21g of KH550 silane coupling agent, 2.8g of vinyl acetate-ethylene copolymer emulsion, 4.2g of propylene glycol, 11.2g of sodium aluminate, 11.2g of water reducer, 0.7g of defoamer, and 597g of water.

[0066] Example 4

[0067] The difference between this embodiment and embodiment 2 is that the formula is different.

[0068] The raw materials of the quick-setting and early-strength pavement repair material of this embodiment are as follows: 890.4g of fast-hardening sulphoaluminate cement, 140g of fly ash, 280g of blast furnace slag powder, 35g of carbide slag, 35g of phosphogypsum, 14g of metakaolin, 5.6g of polyvinyl alcohol powder, 28g of KH550 silane coupling agent, 5.6g of vinyl acetate-ethylene copolymer emulsion, 4.2g of propylene glycol, 11.2g of sodium aluminate, 14g of water reducer, 0.7g of defoamer, and 592.2g of water.

[0069] Example 5

[0070] The difference between this embodiment and embodiment 2 is that the formula is different.

[0071] The raw materials of the quick-setting and early-strength pavement repair material of this embodiment are as follows: 893.2g of fast-hardening sulphoaluminate cement, 140g of fly ash, 280g of blast furnace slag powder, 35g of carbide slag, 35g of phosphogypsum, 14g of metakaolin, 4.2g of polyvinyl alcohol powder, 21g of KH550 silane coupling agent, 2.8g of vinyl acetate-ethylene copolymer emulsion, 4.2g of propylene glycol, 11.2g of sodium aluminate, 11.2g of water reducer, 0.7g of defoamer, and 609g of water.

[0072] Comparative Example 1

[0073] The difference between this comparative example and Example 2 is that this comparative example only contains 1400g of rapid hardening sulphoaluminate cement and 630g of water.

[0074] Comparative Example 2

[0075] The difference between this comparative example and Example 2 is that this comparative example does not contain fly ash, and the missing part is supplemented by blast furnace slag powder.

[0076] Comparative Example 3

[0077] The difference between this comparative example and Example 2 is that this comparative example does not contain blast furnace slag powder, and the missing part is supplemented by fly ash.

[0078] Comparative Example 4

[0079] The difference between this comparative example and Example 2 is that this comparative example does not contain carbide slag, and the missing part is supplemented by fast-hardening sulphoaluminate cement.

[0080] Comparative Example 5

[0081] The difference between this comparative example and Example 2 is that this comparative example does not contain polyvinyl alcohol powder, and the missing part is supplemented by fast-hardening sulphoaluminate cement.

[0082] Comparative Example 6

[0083] The difference between this comparative example and Example 2 is that this comparative example does not contain KH550 silane coupling agent, and the missing part is supplemented by water, and the mass of water is 620.2g.

[0084] Comparative Example 7

[0085] The difference between this comparative example and Example 2 is that this comparative example does not contain vinyl acetate-ethylene copolymer emulsion, and the missing part is supplemented by water, and the mass of water is 597.8g.

[0086] Comparative Example 8

[0087] The difference between this comparative example and Example 2 is that this comparative example does not contain propylene glycol, and the missing part is supplemented by water, and the mass of water is 596.4g.

[0088] Comparative Example 9

[0089] The difference between this comparative example and Example 2 is that the content of propylene glycol in this comparative example is 15 g, and the mass of water is 581.4 g.

[0090] Comparative Example 10

[0091] The difference between this comparative example and Example 2 is that this comparative example does not contain polyvinyl alcohol powder, KH550 silane coupling agent, vinyl acetate-ethylene copolymer emulsion and propylene glycol, and the missing parts are supplemented by fast-hardening sulphoaluminate cement and water. The content of fast-hardening sulphoaluminate cement in this comparative example is 812g, and the mass of water is 630g.

[0092] Test example

[0093] The performance tests of the repair materials of Examples 2 to 5 and Comparative Examples 1 to 10 were carried out, wherein: fluidity: the stirred slurry was injected into a standard truncated cone circular mold, the truncated cone circular mold was lifted, and the maximum diameter of the cement slurry flowing freely on the glass plane was measured; setting time: the initial and final setting times were determined by measuring the change in the sinking depth of the needle in the repair material using a Vicat instrument. The initial setting time is the time when the needle sinks 5±1mm, and the final setting time is the time when the needle cannot completely penetrate the cement paste; Preparation of flexural and compressive strength test specimens of rapid-setting early-strength pavement repair materials: Prepare them using a 40×40×160mm standard mortar specimen triple mold, demold after 2h and wait until a specific age for flexural and compressive strength tests; Preparation of ordinary silicate cement incompletely broken beams simulating crack specimens: Use a 40×40×160mm standard mortar specimen mold and a customized partition to prepare an incompletely broken beam of an ordinary silicate cement standard mortar specimen. The fracture position is the center of the length direction of the cuboid, the fracture width is 3mm, the fracture depth is 30mm, and after demolding, place it under standard curing conditions for 28d. Figure 4 As shown; Bond strength: Pour the repair material into the ordinary Portland cement crack specimen, and use the flexural strength test method to determine the bond strength after 1d / 1d+5 freeze-thaw cycles; Permeability coefficient: Use a concrete impermeability tester to test the permeability coefficient of the repair material. Prepare a standard specimen and put it into the impermeability tester after curing for 28 days. Apply water pressure, measure the water flow and head difference through a flow meter and a pressure sensor, and calculate the permeability coefficient. The test results are shown in Tables 1, 2, and 3.

[0094] Table 1 Test results of fluidity and setting time of the pavement rapid repair materials of the embodiment and the comparative example

[0095]

[0096]

[0097] Note: In Table 1, “-” means not determined.

[0098] Table 2 Mechanical properties and permeability test results of the rapid road repair materials of the embodiment and comparative example

[0099]

[0100]

[0101] Table 3 5h flexural and compressive strength test results of the pavement rapid repair materials in the embodiment

[0102] Serial number 5h flexural strength (MPa) 5h compressive strength (MPa) Example 2 2.9 14.1 Example 3 2.7 14.6 Example 4 3.4 16.2 Example 5 3.0 16.2

[0103] It can be seen from Table 1 that the room temperature and low temperature setting times of the pavement rapid repair material are prolonged with the increase of the content of multi-industrial solid waste, and the influence on the final setting time is greater than that on the initial setting time, and has little correlation with the content of other materials. From the comparison between Example 2 and Comparative Example 6, it can be seen that the addition of KH550 silane coupling agent can effectively reduce the influence of polyvinyl alcohol rubber powder on the fluidity of the material, and the cross-linking of the two improves the dispersion of polyvinyl alcohol rubber powder in the inorganic material. It can be seen from Table 2 that the influencing factors of the flexural strength and bonding strength of the road rapid repair material are ranked according to the influence weight as follows: whether polyvinyl alcohol glue powder is added > whether KH550 silane coupling agent is added > whether vinyl acetate-ethylene copolymer emulsion is added; the main influencing factor of the early compressive strength is the dosage of fast-hardening sulphoaluminate cement; from the comparison between Example 2 and Comparative Examples 2 and 3, it can be seen that the use of blast furnace slag powder instead of fly ash can slightly increase the early compressive strength, but will slightly reduce the later compressive strength, flexural strength and bonding strength, and the use of fly ash instead of blast furnace slag powder can slightly increase the later compressive strength, but will slightly reduce the early compressive strength, flexural strength and bonding strength; from the comparison between Example 2 and Comparative Example 4, it can be seen that the addition of calcium carbide slag can significantly increase the later flexural strength and later compressive strength of the repair material; from the comparison between Example 2 and Comparative Example 7, it can be seen that the addition of vinyl acetate-ethylene copolymer emulsion can significantly reduce the permeability coefficient of the rapid repair material, improve its impermeability and Hydrophobicity reduces the probability of erosion between the pavement repair material and the substrate due to water infiltration; from the comparison between Example 2 and Comparative Examples 7 and 8, it can be seen that vinyl acetate-ethylene copolymer emulsion and propylene glycol have a great influence on the freeze-thaw cycle resistance of the rapid repair material, and the two have a synergistic effect. On the one hand, vinyl acetate-ethylene copolymer emulsion can prevent water from infiltrating into the pavement rapid repair material and the new and old joint surfaces. On the other hand, propylene glycol can lower the freezing point of water and reduce the internal defects of the material caused by condensation and expansion of water; from the comparison between Example 2 and Comparative Example 9, it can be seen that excessive propylene glycol can reduce the attenuation of bonding strength caused by freeze-thaw cycles to a certain extent, but will reduce its flexural strength, compressive strength and bonding strength; from the comparison between Example 2 and Comparative Example 10, it can be seen that when only solid waste materials such as fly ash are added, compared with Example 2, the compressive strength, flexural strength and bonding strength of Comparative Example 10 are reduced, among which the reduction in flexural strength and bonding strength is the most significant. In summary, the embodiments provided by this patent have excellent performance and no obvious shortcomings, and can achieve rapid repair of cement-based pavements.

[0104] The 5h compressive strength of the quick repair materials of Examples 2 to 5 is not less than 14 MPa, and the 5h flexural strength is not less than 2.5 MPa, so the traffic can be opened after 5 hours.

[0105] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A quick-setting and early-strength pavement repair material, characterized in that: Made from the following raw materials by weight: 790-900 parts of rapid-hardening sulphoaluminate cement, 140-210 parts of fly ash, 200-300 parts of blast furnace slag powder, 30-80 parts of carbide slag, 30-80 parts of phosphogypsum, 10-30 parts of metakaolin, 4-6 parts of polyvinyl alcohol, 20-30 parts of silane coupling agent, 2-6 parts of vinyl acetate-ethylene copolymer emulsion, 2-6 parts of propylene glycol, 8-14 parts of sodium aluminate, 10-15 parts of water reducer, 0.5-1 part of defoamer and 580-620 parts of water.

2. The quick-setting and early-strength pavement repair material according to claim 1, characterized in that: The rapid hardening sulphoaluminate cement is of grade 42.5; and the fly ash is of grade II.

3. The quick-setting and early-strength pavement repair material according to claim 1, characterized in that: The particle size of the metakaolin is above 300 meshes, and the particle size of the polyvinyl alcohol powder is between 100 and 200 meshes.

4. The quick-setting and early-strength pavement repair material according to claim 1, characterized in that: The silane coupling agent is KH550 or KH570; the solid content of the vinyl acetate-ethylene copolymer emulsion is 50-60%.

5. The quick-setting and early-strength pavement repair material according to claim 1, characterized in that: The water reducer is selected from any one of naphthalene-based high-efficiency water reducer, aliphatic high-efficiency water reducer, amino high-efficiency water reducer, and polycarboxylic acid high-efficiency water reducer; the defoamer is selected from any one of polyether defoamers, silicone defoamers, and phosphate defoamers.

6. A production device for the quick-setting and early-strength pavement repair material according to any one of claims 1 to 5, characterized in that: It includes a powder feeding device, a powder mixer and a solid-liquid mixing device, wherein the solid-liquid mixing device is located below one side of the powder mixer, and the powder mixer is connected with the solid-liquid mixing device through a conveying channel; The powder mixer is provided with a blower blade, a spiral stirring blade and a stirring bearing; the blower blade is arranged on a side away from the conveying channel and is connected to the blower drive motor; the stirring bearing is connected to the stirring drive motor, and the spiral stirring blade is arranged on the stirring bearing; The solid-liquid mixing device comprises a solid-liquid mixing and stirring pot, a pot cover and a stirring paddle, and a liquid injection hole is arranged on the pot cover.

7. The method for producing a quick-setting and early-strength road repair material according to any one of claims 1 to 5, characterized in that: The production device according to claim 6 comprises the following steps: Rapid hardening sulphoaluminate cement, fly ash, blast furnace slag powder, carbide slag, phosphogypsum, metakaolin, water reducing agent, defoaming agent and sodium metaaluminate are added into the powder mixer through the powder feeding device in proportion, the stirring drive motor is turned on to mix the dry materials, and then the blast drive motor is turned on to transport the dry materials to the transport channel and enter the solid-liquid mixing and stirring pot through the transport channel; Preliminarily, polyvinyl alcohol and a silane coupling agent are fully mixed and heated to react to obtain a polyvinyl alcohol cross-linking reaction liquid; Water is injected into the solid-liquid mixing stirring pot through the injection hole, and then the stirring paddle is turned on for preliminary mixing; then the polyvinyl alcohol cross-linking reaction liquid, vinyl acetate-ethylene copolymer emulsion and propylene glycol are injected into the solid-liquid mixing stirring pot through the injection hole, and the stirring paddle is turned on for formal mixing to obtain the quick-setting and early-strength pavement repair material.

8. The production method according to claim 1, characterized in that The dry material mixing time is 2 to 5 minutes, and the dry material mixing speed is 100 to 200 rpm.

9. The production method according to any one of claims 1 to 8, characterized in that: The rotation speed of the preliminary mixing is 200-300 rpm, and the time of the preliminary mixing is 15-30 s; the rotation speed of the formal mixing is 400-600 rpm, and the time of the formal mixing is 30-60 s.

10. Use of the quick-setting and early-strength pavement repair material according to any one of claims 1 to 5 or the quick-setting and early-strength pavement repair material produced by the production method according to any one of claims 7 to 9 in repairing pavement cracks, characterized in that: The application method is: injecting the quick-setting early-strength pavement repair material into the cracks in the pavement, without special maintenance, and opening the road to traffic after 5 hours.

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