Concrete bridge deck self-repairing drainage pavement structure and construction method thereof

Abstract

This invention belongs to the field of bridge deck pavement technology, specifically relating to a self-healing drainage pavement structure for concrete bridge decks and its construction method. The key technical points are as follows: The pavement structure, from bottom to top, includes: a cement concrete slab base layer, a wet-bonding resin layer, a self-healing porous concrete pavement layer, a high-temperature reactive bonding layer, and a self-healing PA-10 pavement layer. The self-healing porous concrete pavement layer comprises concrete mix and microbial-loaded ceramsite. The microbial-loaded ceramsite is prepared by carbonizing and modifying ceramsite and then loading it with Bacillus subtilis. This invention incorporates pre-loaded microbial ceramsite into a porous cement concrete structure to achieve self-healing of cracks. Combined with the upper large-pore self-healing PA-10 structure, it meets the air and moisture requirements of the microorganisms, effectively enhancing the depth of the microbial self-healing effect, while simultaneously achieving synergistic consistency between drainage and self-healing functions of the upper and lower layers.

Description

Technical Field

[0001] This invention belongs to the field of bridge deck paving technology, specifically relating to a self-healing drainage paving structure for concrete bridge decks and its construction method. Background Technology

[0002] Concrete bridges are widely used due to their low construction cost and simple technical requirements. However, concrete bridges have drawbacks such as heavy weight and easy cracking of the deck panels, which can reflect onto the pavement layer. Furthermore, the stress characteristics of concrete bridge deck pavement differ from those of traditional asphalt pavement. Therefore, using general asphalt pavement design methods can easily lead to insufficient durability of concrete bridge deck pavement and frequent pavement defects.

[0003] To address these issues, current research employs full-thickness concrete pavement to reinforce concrete bridge decks, while utilizing microorganisms that produce calcium carbonate precipitates through biochemical reactions to repair concrete cracks. However, these microbial biochemical reactions require specific moisture and air conditions. Current microbial repair technologies often only repair the concrete surface. Furthermore, directly adding microorganisms during the mixing process severely impacts their activity, negatively affecting the repair effect. Additionally, as a rigid pavement, full-thickness concrete bridge deck pavement offers a certain difference in driving comfort compared to flexible asphalt pavement. Summary of the Invention

[0004] The purpose of this invention is to provide a self-healing drainage pavement structure for concrete bridge decks and its construction method, which can reinforce concrete bridge decks and improve their durability.

[0005] The above-mentioned technical objective of the present invention is achieved through the following technical solution:

[0006] The present invention provides a self-healing drainage pavement structure for concrete bridge deck, which, from top to bottom, includes: a cement concrete slab base layer, a wet bonding resin layer, a self-healing porous concrete pavement layer, a high-temperature reactive bonding layer, and a self-healing PA-10 pavement layer.

[0007] The materials for the self-healing porous concrete pavement include concrete mix and bacteria-carrying ceramsite.

[0008] Bacterial-loaded ceramsite is prepared by loading Bacillus spores onto ceramsite after carbonization modification.

[0009] Furthermore, the total thickness of the paving structure provided by the present invention is 5~10cm, the thickness of the wet bonding resin layer is 1~2mm, the thickness of the self-healing porous concrete paving layer is 4~6cm, the thickness of the high-temperature reactive bonding layer is 1~2mm, and the thickness of the self-healing PA-10 paving layer is 3~5cm.

[0010] In this invention, a wet bonding resin layer and a high-temperature reactive bonding layer are combined to further enhance the bonding ability between pavement layers. Self-healing porous concrete is used as the lower pavement layer to reinforce the concrete bridge deck, while self-healing asphalt concrete PA-10 is used as the upper pavement layer, creating a synergistic effect to meet the comfort requirements of road driving.

[0011] Both the self-healing porous concrete pavement layer and the self-healing asphalt concrete PA-10 pavement layer are porous structures, forming a double-pore structure between the two layers. This not only improves the drainage capacity of the road surface but also meets the requirements for moisture and air in the microbial self-healing technology, enabling the upper and lower pavement layers to repair themselves in synergy. This effectively improves the crack resistance of the pavement structure and prevents cracks from spreading.

[0012] In this invention, the ceramic granule carrier loaded with Bacillus spores was also carbonized. After carbonization, the pH value of the ceramic granule surface was reduced, making it more suitable for Bacillus spores to attach and survive, while also improving the strength of the bacterial-loaded ceramic granules.

[0013] Furthermore, the method for loading Bacillus onto ceramsite includes impregnating carbonized and modified porous ceramsite with a Bacillus suspension under vacuum negative pressure, followed by drying. Preferably, the impregnation is performed for 30 minutes to allow the ceramsite to fully absorb the Bacillus, and then it is dried in an oven at a constant temperature.

[0014] Furthermore, in this invention, the method for carbonizing and modifying porous ceramsite includes placing the porous ceramsite in a carbonization box and adjusting the degree of carbonization of the porous ceramsite according to the CO2 concentration, carbonization temperature, and carbonization time in the carbonization box.

[0015] Due to the limitations of Bacillus growth conditions, the degree of carbonization of ceramsite needs to be controlled. If the degree of carbonization is too low, it cannot improve the surface pH value; if the degree of carbonization is too high, it will lead to a decrease in the strength of the ceramsite and will also be detrimental to the growth and reproduction of Bacillus.

[0016] Therefore, in this invention, by controlling the CO2 concentration, carbonization temperature and carbonization time in the carbonization box, the carbonization degree of the ceramsite is controlled at 20%~30%; at the same time, the particle size of the carbonized and modified ceramsite is 1~4mm, the water absorption rate is 1~3%, and the Mohs hardness is 6~8.

[0017] Furthermore, the parameters of the carbonization box are set as follows: CO2 concentration of 2%~100%, carbonization temperature of 5~50℃, relative humidity of 30%~70%, and carbonization time of 24h.

[0018] Furthermore, the cultivation method for Bacillus includes culturing the Bacillus bacterial culture in a culture medium, followed by centrifugation, sedimentation, and resuspending to prepare a Bacillus suspension. Preferably, the Bacillus strain is cultured in LB liquid medium at pH 7-7.5 for 24-26 hours until the OD of the bacterial suspension is... 400 The value was 2.650~2.850, and the enzyme activity was 0.025~0.029 μmol / min. Subsequently, the Bacillus suspension was supported by centrifugation, precipitation, and resuspension.

[0019] The culture conditions provided by this invention enable the concentration and activity of microorganisms to be more adapted to the internal and external environment of the paving structure in this invention, and produce the most efficient repair substances under biochemical action.

[0020] Furthermore, the amount of bacteria-loaded ceramsite added is 8% to 20% of the concrete mass.

[0021] Furthermore, based on the mass ratio, the concrete mix is ​​as follows: water:sand:natural crushed stone:cement = (0.4~0.5):(3.0~3.4):(1.5~2.0):(1.0~1.6).

[0022] Furthermore, the materials for the self-healing PA-10 pavement layer include high-viscosity modified asphalt, basalt aggregate, polyester fiber, and asphalt repair capsules. The basalt aggregate is divided into coarse aggregate, fine aggregate, and mineral powder; the preferred mass ratio of this material is coarse aggregate: fine aggregate: mineral powder: asphalt repair capsule = (78~81):(12~14.5):(1.5~3):(2~3), with an asphalt-aggregate ratio of 5.1%~5.5%, and a polyester fiber content of 0.2%~0.6%.

[0023] After the above formula is prepared, the porosity of the self-healing PA-10 paving layer is 14~22%. In this invention, the porosity is controlled within this range. While ensuring the strength of the paving layer, sufficient moisture and air are provided to the Bacillus in the ceramsite, which effectively improves the bioremediation ability of the Bacillus.

[0024] Furthermore, the asphalt repair capsule uses asphalt rejuvenator as the core and sodium alginate colloid as the outer wall.

[0025] Furthermore, the asphalt recycling agent, calculated by weight, includes the following components: 10-20 parts soybean oil, 10-15 parts corn oil, 1-5 parts waste rubber powder, 0.5-2 parts epoxidized soybean oil, 0.5-20 parts alkyl-substituted phenolic polyoxyethylene ether, and 1-10 parts dialkyl dithiophosphate.

[0026] The asphalt recycling agent is brownish-black in appearance, has a pH value of 9.5~10.5, an active ingredient content of 40%~60%, and an Engler viscosity E25 of 6~7.

[0027] Furthermore, the preparation method of the asphalt recycling agent is as follows: after mixing the above materials in proportion, heat to 100~120℃ and keep at a constant temperature, then stir at 600~800r / min for 20~30min to obtain the product.

[0028] Furthermore, the preparation method of the asphalt repair capsule is as follows: 1-2 parts of asphalt rejuvenator and 6-8 parts of sodium alginate are mixed according to the mass fraction, and the mixture is stirred at 3000-5000 rpm for 10-20 minutes to obtain an emulsion; the emulsion is titrated into a 2-4% calcium chloride solution and stirred at 600-800 rpm for 2 hours; finally, the calcium chloride solution containing the emulsion is ventilated at room temperature to remove moisture, thus obtaining the asphalt repair capsule.

[0029] Furthermore, the softening point of the high-viscosity modified asphalt is 106~108℃, the penetration is 46~47cm, the ductility is 88~90cm, the viscosity at 60℃ is 56000~58000 Pa·s, and the stability is 0.1℃.

[0030] Furthermore, according to the weight parts, the material of the high-temperature reactive adhesive layer provided by the present invention includes the following components: 70-80 parts of linear phenolic polyglycidyl ether, 10-20 parts of monofunctional reactive diluent, 1-3 parts of epoxy silane coupling agent, 10-20 parts of linear difunctional secondary amine curing agent, 3-10 parts of adipic acid dihydrazide curing agent, and 1-2 parts of anti-settling agent.

[0031] Furthermore, according to the weight parts, the material of the wet bonding resin layer provided by the present invention includes the following components: 65-70 parts of epoxy resin, 12-16 parts of polyamide curing agent, 5-10 parts of polyisocyanate adhesive, 2-5 parts of polyether resin active toughening agent and 2-5 parts of quartz powder waterborne reinforcing agent.

[0032] The second objective of this invention is to provide a construction method for a self-healing drainage pavement structure for concrete bridge decks, which has the same technical effect.

[0033] The above-mentioned technical objective of the present invention is achieved by the following technical solution:

[0034] The construction method for the self-healing drainage pavement structure of concrete bridge deck provided by this invention specifically includes the following steps:

[0035] S1. Milling is performed on the cement concrete slab base; preferably, the milling is ultra-precision milling with a milling depth of 2-3 mm. After milling, the surface is shot blasted to obtain a cement concrete slab base with good roughness and cleanliness.

[0036] S2. Spray the material of the wet bonding resin layer onto the cement concrete slab substrate to form a wet bonding resin layer; specifically, within 2 hours after shot blasting, spray the material of the wet bonding resin layer at a rate of 1~2 kg / m². 2 Spray onto cement concrete slab substrate;

[0037] S3. The material of the self-healing porous concrete pavement layer is laid on the wet bonding resin layer to form a self-healing porous concrete pavement layer.

[0038] S4. After removing debris from the surface of the self-healing porous concrete pavement, evenly apply the material of the high-temperature reactive adhesive layer to its surface to form the high-temperature reactive adhesive layer; the specific application rate is 0.5~0.6 kg / m². 2 Apply evenly;

[0039] S5. A self-healing PA-10 paving layer is laid on the surface of the high-temperature reactive adhesive layer to form a self-healing PA-10 paving layer.

[0040] Furthermore, the specific operation of step S3 is as follows:

[0041] S31. Use a horizontal mixer to mix the dry mixture for 1 minute at a rate of 25~35 rpm / min;

[0042] S32. Then add mixing water and wet mix for 5-8 minutes to form a self-healing porous concrete pavement layer material.

[0043] S33. Paving, control the vibration spacing to be 0.5~1.0m, and the vibration time for each section to be 10~20s;

[0044] S34. After compaction, before initial setting, perform surface polishing and after final setting, roughen the surface to enhance adhesion and improve interlayer bonding.

[0045] S35. Then spray water mist and cover with a film for 14 days to maintain moisture and form a self-healing porous concrete pavement layer.

[0046] Furthermore, the specific operation of step S5 is as follows:

[0047] S51. Weigh out coarse aggregate, fine aggregate, mineral powder, asphalt repair capsules and polyester fiber by mass.

[0048] S52. Use a horizontal mixer to dry mix at a rate of 30~45 rpm / min for 15~25 seconds;

[0049] S53. Then, add high-viscosity modified asphalt at an asphalt-aggregate ratio of 5.1-5.5% and mix for 40-55 seconds to form self-healing PA-10 mixture.

[0050] S54. Paving: Control the paving temperature to above 165℃ and the initial compaction temperature to above 155℃. Use a steel wheel roller for initial compaction and secondary compaction, with 2 to 4 compaction cycles.

[0051] S55. Finally, a rubber-tired roller is used for final compaction, with 1 to 2 compaction cycles, to form a self-healing PA-10 pavement layer.

[0052] Furthermore, the self-healing porous concrete pavement layer must be laid within 1 hour of the formation of the wet bonding resin layer.

[0053] Furthermore, the self-healing PA-10 paving layer must be laid within 1 hour after the high-temperature reactive adhesive layer is applied.

[0054] In summary, the present invention has the following beneficial effects:

[0055] (1) The present invention uses a wet bonding resin layer that is cured synchronously with cement concrete pavement and a high-temperature reactive bonding layer that is cured synchronously with asphalt concrete as waterproof bonding layers to enhance the connection between pavement layers, thereby improving the overall interface connection, structural synergy stability and interlayer anti-slip performance of the pavement.

[0056] (2) The porous cement concrete structure is mixed with preloaded microorganisms in the ceramsite to achieve the self-repair function of cracking. Combined with the upper large-pore self-repair PA-10 structure to meet the air and water requirements of microorganisms, the depth of microbial self-repair is effectively improved, and the drainage and self-repair functions of the upper and lower layers are coordinated and consistent.

[0057] (3) Compared with the full-thickness concrete pavement structure, the self-healing drainage pavement structure of the concrete bridge deck provided by the present invention uses a porous concrete pavement lower layer to reinforce the concrete bridge deck, and uses a PA-10 asphalt concrete pavement upper layer to reduce the bridge deck load and ensure the safety and comfort of driving. Attached Figure Description

[0058] Figure 1 This is a schematic diagram of a self-healing drainage pavement structure for a concrete bridge deck, as described in an embodiment of the present invention.

[0059] Figure Labels

[0060] 1-Cement concrete slab base layer, 2-Wet bonding resin layer, 3-Self-healing porous concrete pavement layer, 4-High temperature reactive bonding layer, 5-Self-healing PA-10 pavement layer. Detailed Implementation

[0061] To further illustrate the technical means and effects adopted by the present invention to achieve the intended purpose, the specific implementation method, features and effects of a self-healing drainage pavement structure for concrete bridge decks and its construction method proposed according to the present invention are described in detail below.

[0062] A self-healing drainage pavement structure for concrete bridge decks and its construction method

[0063] like Figure 1 As shown in the specific embodiment, the total thickness of the paving structure is 5~10cm, and from bottom to top, it consists of: cement concrete slab base layer 1; wet bonding resin layer 2, with a thickness of 1~2mm; self-healing porous concrete paving layer 3, with a thickness of 4~6cm; high-temperature reactive bonding layer 4, with a thickness of 1~2mm; and self-healing PA-10 paving layer 5, with a thickness of 3~5cm.

[0064] The wet bonding resin layer 2, calculated by weight, comprises: 65-70 parts epoxy resin, 12-16 parts polyamide curing agent, 5-10 parts polyisocyanate adhesive, 4-6 parts butyl glycidyl ether reactive diluent, 2-5 parts polyether resin reactive toughening agent, and 2-5 parts quartz powder waterborne reinforcing agent.

[0065] The materials of the self-healing porous concrete pavement layer 3 include: concrete and bacterial-loaded ceramsite, with the bacterial-loaded ceramsite content being 8%~20% of the concrete mass; according to the mass ratio, the concrete mix is: water:sand:natural crushed stone:cement = (0.4~0.5):(3.0~3.4):(1.5~2.0):(1.0~1.6).

[0066] The bacterial-carrying ceramic particles consist of carbonized modified porous ceramic particle carriers and Bacillus spores loaded on the ceramic particle carriers. Specifically, the carbonized modified porous ceramic particles are impregnated with a Bacillus spore suspension for 30 minutes under vacuum negative pressure conditions. After full adsorption, they are placed in an oven for constant temperature drying.

[0067] The carbonized modified porous ceramsite has a particle size of 1-4 mm, a water absorption rate of 1-3%, a moisture content of 0.3-1.3%, a Mohs hardness of 6-8, and a carbonization degree of 20-30%. The following modification method is used: the screened porous ceramsite is evenly spread and placed in a carbonization box. The CO2 concentration in the carbonization box is set to 2%-100%, the carbonization temperature to 5℃-50℃, and the relative humidity to 30%-70%. The carbonization treatment is carried out for 24 hours.

[0068] Bacillus bacterial suspension was obtained by culturing Bacillus strains in LB liquid medium at 35°C for 24 hours, followed by centrifugation and resuspension to prepare a Bacillus suspension. Specifically, the Bacillus suspension was prepared by culturing Bacillus strains in LB liquid medium at pH 7-7.5 for 24-26 hours, until the OD of the bacterial suspension was determined. 400The value was 2.650~2.850, and the enzyme activity was 0.025~0.029 μmol / min. Subsequently, a Bacillus suspension was prepared by centrifugation, precipitation and resuspension. At this time, the microbial concentration and activity were good, and the efficiency of producing repair substances under biochemical action was the highest.

[0069] According to the weight parts, the high-temperature reactive adhesive layer 4 includes the following components: 70-80 parts of linear phenolic polyglycidyl ether, 10-20 parts of monofunctional reactive diluent, 1-3 parts of epoxy silane coupling agent, 10-20 parts of linear difunctional secondary amine curing agent, 3-10 parts of adipic acid dihydrazide curing agent, and 1-2 parts of anti-settling agent.

[0070] The materials for the self-healing PA-10 pavement layer 5 include high-viscosity modified asphalt, basalt aggregate, polyester fiber, and asphalt repair capsules. The basalt aggregate is further divided into coarse aggregate, fine aggregate, and mineral powder.

[0071] The preferred mass ratio of the self-healing PA-10 pavement layer 5 is coarse aggregate: fine aggregate: mineral powder: asphalt repair capsule = (78~81): (12~14.5): (1.5~3): (2~3), the asphalt-aggregate ratio is 5.1%~5.5%, and the polyester fiber content is 0.2%~0.6%.

[0072] The softening point of the high-viscosity modified asphalt is 106~108℃, the penetration is 46~47cm, the ductility is 88~90cm, the viscosity at 60℃ is 56000pa·s~58000pa·s, and the stability is 0.1℃.

[0073] The asphalt repair capsule consists of an asphalt rejuvenator as the core and sodium alginate colloid as the outer wall.

[0074] The asphalt recycling agent is brownish-black in appearance, with a pH value of 9.5~10.5, an active ingredient content of 40%~60%, and an Engler viscosity E25 of 6~7. Calculated by weight, it includes the following components: 10~20 parts soybean vegetable oil, 10~15 parts corn vegetable oil, 1~5 parts waste rubber powder, 0.5~2 parts epoxidized soybean oil, 0.5~20 parts alkyl-substituted phenolic polyoxyethylene ether, and 1~10 parts dialkyl dithiophosphate.

[0075] The preparation method of asphalt repair capsules is as follows: 6-8 parts by weight of sodium alginate solution and 1-2 parts by weight of asphalt rejuvenator are mixed and stirred at 3000-5000 rpm for 10-20 minutes until an emulsion is reached. The emulsion is then titrated into a 2-4% calcium chloride solution and stirred at 600-800 rpm for 2 hours. Finally, the calcium chloride solution containing the emulsion is ventilated at room temperature to remove moisture and obtain asphalt repair capsules.

[0076] This specific embodiment also provides a construction method for a self-healing drainage pavement structure for concrete bridge decks, including the following steps:

[0077] S1. Milling treatment is performed on the cement concrete slab base layer 1;

[0078] S2. Spray the material of the wet bonding resin layer 2 onto the cement concrete slab base layer 1 to form the wet bonding resin layer 2.

[0079] S3. The material of the self-healing porous concrete pavement layer 3 is laid on the wet bonding resin layer 2 to form the self-healing porous concrete pavement layer 3.

[0080] S4. After removing the surface debris of the self-healing porous concrete pavement layer 3, the material of the high-temperature reactive adhesive layer 4 is evenly applied to its surface to form the high-temperature reactive adhesive layer 4.

[0081] S5. A self-healing PA-10 pavement layer 5 is laid on the surface of the high-temperature reactive adhesive layer 4 to form the self-healing PA-10 pavement layer 5.

[0082] The specific operation of step S3 is as follows:

[0083] S31. Use a horizontal mixer to mix the dry mixture for 1 minute at a rate of 25~35 rpm / min;

[0084] S32. Then add mixing water and wet mix for 5-8 minutes to form a self-healing porous concrete pavement layer material.

[0085] S33. Paving, control the vibration spacing to be 0.5~1.0m, and the vibration time for each section to be 10~20s;

[0086] S34. After compaction, before initial setting, perform surface polishing and after final setting, roughen the surface to enhance adhesion and improve interlayer bonding.

[0087] S35. Then spray water mist and cover with a film for 14 days to maintain moisture and form a self-healing porous concrete pavement layer 3.

[0088] The specific operation of step S5 is as follows:

[0089] S51. Weigh out coarse aggregate, fine aggregate, mineral powder, asphalt repair capsules and polyester fiber by mass.

[0090] S52. Use a horizontal mixer to dry mix at a rate of 30~45 rpm / min for 15~25 seconds;

[0091] S53. Then, add high-viscosity modified asphalt at an asphalt-aggregate ratio of 5.1-5.5% and mix for 40-55 seconds to form self-healing PA-10 mixture.

[0092] S54. Paving: Control the paving temperature to above 165℃ and the initial compaction temperature to above 155℃. Use a steel wheel roller for initial compaction and secondary compaction, with 2 to 4 compaction cycles.

[0093] S55. Finally, a rubber-tired roller is used for final compaction, with 1 to 2 compaction cycles, to form a self-healing PA-10 pavement layer 5.

[0094] It should be noted that the self-healing porous concrete pavement layer should be laid within 1 hour of the formation of the wet bonding resin layer; the self-healing PA-10 pavement layer should be laid within 1 hour after the application of the high-temperature reactive bonding layer.

[0095] Example 1: A self-healing drainage pavement structure for concrete bridge decks and its construction method

[0096] This embodiment addresses the pavement of a concrete viaduct in Jiangsu Province. The pavement suffers from severe cracking and damage, causing vehicles to experience bumpy rides, requiring significant maintenance costs, and severely impacting driving safety and economic efficiency. The pavement structure and construction method described in this embodiment are employed for repaving, as detailed below.

[0097] The paving structure in this embodiment is as follows, from bottom to top: 1. Cement concrete slab base layer; 2. Wet bonding resin layer with a thickness of 1~2mm; 3. Self-healing porous concrete paving layer with a thickness of 6cm; 4. High-temperature reactive bonding layer with a thickness of 1~2mm; 5. Self-healing PA-10 paving layer with a thickness of 4cm.

[0098] The material composition used in this embodiment, calculated by weight, is as follows:

[0099] The materials of the wet bonding resin layer 2 are: 65 parts epoxy resin, 13 parts polyamide curing agent, 6 parts polyisocyanate adhesive, 4 parts butyl glycidyl ether reactive diluent, 2 parts polyether resin reactive toughening agent and 3 parts quartz powder waterborne reinforcing agent.

[0100] The materials for the self-healing porous concrete pavement layer 3 are as follows: 13 parts silicate cement, 16 parts natural crushed stone, 34 parts sand, and 12 parts bacterial-loaded ceramsite.

[0101] Among them, the bacteria-carrying ceramic particles consist of carbonized modified porous ceramic particle carriers and Bacillus spores loaded on the ceramic particle carriers. Specifically, the carbonized modified porous ceramic particles are immersed in a Bacillus spore suspension for 30 minutes under vacuum negative pressure conditions, and after full adsorption, they are placed in an oven for constant temperature drying.

[0102] The carbonized modified porous ceramsite has a particle size of 1~4mm, a water absorption rate of 1~3%, a moisture content of 0.3~1.3%, a Mohs hardness of 6~8, and a carbonization degree of 20~30%. The following modification method is used: the screened porous ceramsite is evenly spread and placed in a carbonization box. The CO2 concentration of the carbonization box is set to 35%, the carbonization temperature to 30℃, and the relative humidity to 55%. The carbonization treatment is carried out for 24 hours.

[0103] Bacillus bacterial suspension was obtained by culturing Bacillus strain in LB liquid medium at 35°C for 24 hours, followed by centrifugation and resuspension to prepare a Bacillus suspension. Specifically, the Bacillus suspension was prepared by culturing Bacillus strain in LB liquid medium at pH 7.5 for 26 hours, until the OD of the bacterial suspension was... 400 The value was 2.800, and the enzyme activity was 0.028 μmol / min. Subsequently, a Bacillus suspension was prepared by centrifugation, precipitation, and resuspension.

[0104] The materials of the high-temperature reactive adhesive layer 4 are as follows: 70 parts linear phenolic polyglycidyl ether, 10 parts monofunctional reactive diluent, 1 part epoxy silane coupling agent, 10 parts linear difunctional secondary amine curing agent, 4 parts adipic acid dihydrazide curing agent and 1 part anti-settling agent.

[0105] The materials for self-healing PA-10 pavement layer 5 are as follows: 5.4% asphalt-aggregate ratio high-viscosity modified asphalt, 78 parts coarse aggregate of basalt, 12 parts fine aggregate, 2 parts mineral powder, 2 parts asphalt repair capsules, and 0.3% polyester fiber content. First, the coarse aggregate, fine aggregate, mineral powder and asphalt repair capsules of basalt are dry-mixed for 15 seconds at a speed of 45 rpm using a horizontal mixer. Then, high-viscosity modified asphalt with a 5.4% asphalt-aggregate ratio is added and mixed wet for 45 seconds to form self-healing PA-10 mixture.

[0106] The softening point of the high-viscosity modified asphalt is 106~108℃, the penetration is 46~47cm, the ductility is 88~90cm, the viscosity at 60℃ is 56000pa·s~58000pa·s, and the stability is 0.1℃.

[0107] The asphalt repair capsule consists of an asphalt rejuvenator as the core and sodium alginate colloid as the outer wall.

[0108] The asphalt recycling agent is brownish-black in appearance, with a pH value of 9.5~10.5, an active ingredient content of 40%~60%, and an Engler viscosity E25 of 6~7. Calculated by weight, it includes the following components: 15 parts soybean vegetable oil, 10 parts corn vegetable oil, 2 parts waste rubber powder, 0.5 parts epoxidized soybean oil, 5 parts alkyl-substituted phenolic polyoxyethylene ether, and 3 parts dialkyl dithiophosphate.

[0109] The preparation method of asphalt repair capsules is as follows: 6 parts sodium alginate solution and 1 part asphalt rejuvenator are mixed according to the mass ratio, and stirred at 4000 rpm for 20 minutes until an emulsion is reached. Then, the emulsion is titrated into a 2% calcium chloride solution and stirred at 800 rpm for 2 hours. Finally, the calcium chloride solution containing the emulsion is ventilated at room temperature to remove moisture and obtain asphalt repair capsules.

[0110] The construction method is as follows:

[0111] S1. Milling and excavating the original pavement, milling the concrete bridge deck with 2mm ultra-precision milling, and then shot blasting the deck to obtain a rough and clean cement concrete slab base layer 1.

[0112] S2. Two hours after milling and shot blasting the concrete panel, apply 1.8 kg / m² of shot blasting material to the cement concrete slab base layer. 2 Materials for spraying wet bonding resin layers;

[0113] S3. Use a horizontal mixer to mix the dry mixture for 1 minute at a speed of 35 rpm, then add mixing water and wet mix for 6 minutes to form self-healing porous concrete. Then lay it on the wet bonding resin layer, control the vibration spacing to 0.6m, and the vibration time at each location to 15s. After compaction, perform surface polishing before initial setting, and roughen the surface after final setting. Then spray water mist and cover with film for moist curing for 14 days.

[0114] S4. Remove the laitance and loose debris from the surface of the self-healing porous concrete pavement layer 3. Apply the high-temperature reactive bonding layer material evenly, controlling the application rate to 0.5~0.6 kg / m². 2 Forming a high-temperature reactive adhesive layer 4;

[0115] S5. Within 1 hour of applying the high-temperature reactive bonding layer 4, lay the self-healing PA-10 pavement layer 5. Lay the self-healing PA-10 mixture on the high-temperature reactive bonding layer 4, control the paving temperature to be above 165℃, control the initial compaction temperature to be above 155℃, use a steel wheel roller for initial compaction and secondary compaction, and compact 3 times. Finally, use a rubber-tired roller for final compaction, and compact 2 times to form the self-healing PA-10 pavement layer 5.

[0116] The pavement structure provided in this embodiment has shown no cracks or defects after one year of service, effectively solving the cracking problem. It also exhibits significant drainage during rainfall, with a lateral force coefficient of 57 and a structural depth of 1.1 mm, effectively ensuring driving safety. Test data compared to existing concrete bridge deck pavements are shown in Table 1.

[0117] Table 1. Performance data comparison between the pavement structure of Example 1 and existing pavement structures.

[0118]

[0119] As can be seen from the above, the performance of the self-healing drainage pavement structure for concrete bridge decks provided in this embodiment is significantly better than that of existing concrete bridge deck pavements, and it has industrial value.

[0120] Example 2: A self-healing drainage pavement structure for concrete bridge decks and its construction method

[0121] The self-healing drainage pavement structure for concrete bridge decks provided in this embodiment consists of, from bottom to top: a cement concrete slab base layer 1; a wet bonding resin layer 2 with a thickness of 1-2 mm; a self-healing porous concrete pavement layer 3 with a thickness of 5 cm; a high-temperature reactive bonding layer 4 with a thickness of 1-2 mm; and a self-healing PA-10 pavement layer 5 with a thickness of 5 cm.

[0122] The material composition used in this embodiment, calculated by weight, is as follows:

[0123] The materials of the wet bonding resin layer 2 are: 65 parts epoxy resin, 13 parts polyamide curing agent, 6 parts polyisocyanate adhesive, 4 parts butyl glycidyl ether reactive diluent, 2 parts polyether resin reactive toughening agent and 3 parts quartz powder waterborne reinforcing agent.

[0124] The materials for the self-healing porous concrete pavement layer 3 are as follows: 14 parts silicate cement, 16 parts natural crushed stone, 33 parts sand, and 15 parts bacterial-loaded ceramsite.

[0125] Among them, the bacteria-carrying ceramic particles consist of carbonized modified porous ceramic particle carriers and Bacillus spores loaded on the ceramic particle carriers. Specifically, the carbonized modified porous ceramic particles are immersed in a Bacillus spore suspension for 30 minutes under vacuum negative pressure conditions, and after full adsorption, they are placed in an oven for constant temperature drying.

[0126] The carbonized modified porous ceramsite has a particle size of 1~4mm, a water absorption rate of 1~3%, a moisture content of 0.3~1.3%, a Mohs hardness of 6~8, and a carbonization degree of 20~30%. The following modification method is used: the screened porous ceramsite is evenly spread out and placed in a carbonization box. The CO2 concentration of the carbonization box is set to 30%, the carbonization temperature to 25℃, and the relative humidity to 40%. The carbonization treatment is carried out for 24 hours.

[0127] Bacillus bacterial suspension was obtained by culturing Bacillus strain in LB liquid medium at 35°C for 24 hours, followed by centrifugation and resuspension to prepare a Bacillus suspension. Specifically, the Bacillus suspension was prepared by culturing Bacillus strain in LB liquid medium at pH 7.5 for 25 hours, until the OD of the bacterial suspension was... 400 The value was 2.850, and the enzyme activity was 0.027 μmol / min. Subsequently, a Bacillus suspension was prepared by centrifugation, precipitation, and resuspension.

[0128] The materials of the high-temperature reactive adhesive layer 4 are as follows: 70 parts linear phenolic polyglycidyl ether, 10 parts monofunctional reactive diluent, 1 part epoxy silane coupling agent, 10 parts linear difunctional secondary amine curing agent, 4 parts adipic acid dihydrazide curing agent and 1 part anti-settling agent.

[0129] The materials for self-healing PA-10 pavement layer 5 are as follows: 5.4% asphalt-aggregate ratio high-viscosity modified asphalt, 73 parts basalt coarse aggregate, 13 parts fine aggregate, 3 parts mineral powder, 3 parts asphalt repair capsules, and 0.3% polyester fiber from Shandong. First, the basalt coarse aggregate, fine aggregate, mineral powder, and asphalt repair capsules are dry-mixed for 15 seconds at a speed of 45 rpm using a horizontal mixer. Then, high-viscosity modified asphalt with a 5.4% asphalt-aggregate ratio is added and mixed wet for 45 seconds to form the self-healing PA-10 mixture.

[0130] The softening point of the high-viscosity modified asphalt is 106~108℃, the penetration is 46~47cm, the ductility is 88~90cm, the viscosity at 60℃ is 56000pa·s~58000pa·s, and the stability is 0.1℃.

[0131] The asphalt repair capsule consists of an asphalt rejuvenator as the core and sodium alginate colloid as the outer wall.

[0132] The asphalt recycling agent is brownish-black in appearance, with a pH value of 9.5~10.5, an active ingredient content of 40%~60%, and an Engler viscosity E25 of 6~7. Calculated by weight, it includes the following components: 10 parts soybean vegetable oil, 12 parts corn vegetable oil, 1 part waste rubber powder, 1 part epoxidized soybean oil, 8 parts alkyl-substituted phenolic polyoxyethylene ether, and 2 parts dialkyl dithiophosphate.

[0133] The preparation method of asphalt repair capsules is as follows: 8 parts sodium alginate solution and 1.5 parts asphalt rejuvenator are mixed according to the mass ratio, and stirred at 3500 rpm for 20 minutes until an emulsion is reached. Then, the emulsion is titrated into a 3% calcium chloride solution and stirred at 650 rpm for 2 hours. Finally, the calcium chloride solution containing the emulsion is ventilated at room temperature to remove moisture and obtain asphalt repair capsules.

[0134] The construction method is as follows:

[0135] S1. Milling and excavating the original pavement, milling the concrete bridge deck with 2 mm ultra-precision milling, and then shot blasting the deck to obtain a rough and clean cement concrete slab base 1.

[0136] S2. Two hours after milling and shot blasting the concrete panel, apply 1.8 kg / m² of shot blasting material to the cement concrete slab base layer. 2 Materials for spraying wet bonding resin layers;

[0137] S3. Use a horizontal mixer to mix the dry mixture for 1 minute at a speed of 35 rpm, then add mixing water and wet mix for 6 minutes to form self-healing porous concrete. Then lay it on the wet bonding resin layer, control the vibration spacing to 0.8m, and the vibration time at each location to 15s. After compaction, perform surface polishing before initial setting, and roughen the surface after final setting. Then spray water mist and cover with film for moist curing for 14 days.

[0138] S4. Remove laitance and loose debris from the surface of the self-healing porous concrete pavement layer 3. Apply the high-temperature reactive bonding layer material evenly, controlling the application rate to 0.6 kg / m². 2 Forming a high-temperature reactive adhesive layer 4;

[0139] S5. Within 1 hour of applying the high-temperature reactive bonding layer 4, lay the self-healing PA-10 pavement layer 5. Lay the self-healing PA-10 mixture on the high-temperature reactive bonding layer 4, control the paving temperature to be above 165℃, control the initial compaction temperature to be above 155℃, use a steel wheel roller for initial compaction and secondary compaction, and compact 3 times. Finally, use a rubber-tired roller for final compaction, and compact once to form the self-healing PA-10 pavement layer 5.

[0140] The pavement structure provided in this embodiment has an interlayer pull-out strength higher than 2.5MPa. After two years of service, only a small number of micro-cracks and no interlayer displacement defects have occurred, effectively solving the problems of interlayer displacement and crack defects. It has a significant drainage effect in rainy weather, a lateral force coefficient of 55, and a structural depth of 1.01mm, effectively ensuring driving safety.

[0141] Compared with existing concrete bridge deck pavement structures, its performance data is shown in Table 2.

[0142] Table 2. Performance Comparison of Example 2 and Existing Concrete Bridge Deck Pavement Structures

[0143]

[0144] Based on the above data, it can be seen that the pavement structure provided by the present invention can not only improve the pull-out strength and structural depth, but also improve the pavement damage index.

[0145] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Although the present invention has been shown above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the present invention. Any simple modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the scope of the present invention.

Claims

1. A self-healing drainage pavement structure for concrete bridge decks, characterized in that, The paving structure, from bottom to top, includes: a cement concrete slab base layer, a wet bonding resin layer, a self-healing porous concrete paving layer, a high-temperature reactive bonding layer, and a self-healing PA10 paving layer. The self-healing porous concrete pavement layer is made of concrete mix ingredients and bacteria-carrying ceramsite. The bacterial-carrying ceramsite is prepared by carbonizing porous ceramsite in a carbonization box, adjusting the carbonization degree of the porous ceramsite to 20%~30% according to the CO2 concentration, carbonization temperature and carbonization time in the carbonization box; the ceramsite particle size after carbonization modification is 1~4mm, the water absorption rate is 1~3%, and the Mohs hardness is 6~8. Then, the carbonized and modified porous ceramsite is impregnated with Bacillus suspension under vacuum negative pressure and then dried. The materials of the self-healing PA10 pavement layer include high-viscosity modified asphalt, basalt aggregate, polyester fiber, and asphalt repair capsules. The basalt aggregate is divided into coarse aggregate, fine aggregate, and mineral powder. The mass ratio of the material is coarse aggregate: fine aggregate: mineral powder: asphalt repair capsule = (78~81):(12~14.5):(1.5~3):(2~3), the asphalt-aggregate ratio is 5.1%~5.5%, and the polyester fiber content is 0.2%~0.6%. The porosity of the self-healing PA-10 pavement layer is 14~22%. The asphalt repair capsule has asphalt rejuvenator as the core and sodium alginate colloid as the outer wall.

2. The self-healing drainage pavement structure for concrete bridge decks according to claim 1, characterized in that, The method of culturing Bacillus includes placing Bacillus bacterial solution in a culture medium for cultivation, followed by centrifugation, sedimentation, and resuspension to prepare a Bacillus suspension.

3. The self-healing drainage pavement structure for concrete bridge decks according to claim 1, characterized in that, The asphalt rejuvenator, calculated by weight, comprises the following components: 10-20 parts soybean oil, 10-15 parts corn oil, 1-5 parts waste rubber powder, 0.5-2 parts epoxidized soybean oil, 0.5-20 parts alkyl-substituted phenolic polyoxyethylene ether, and 1-10 parts dialkyl dithiophosphate.

4. The self-healing drainage pavement structure for concrete bridge decks according to claim 1, characterized in that, The high-temperature reactive adhesive layer comprises the following components by weight: 70-80 parts of linear phenolic polyglycidyl ether, 10-20 parts of monofunctional reactive diluent, 1-3 parts of epoxy silane coupling agent, 10-20 parts of linear difunctional secondary amine curing agent, 3-10 parts of adipic acid dihydrazide curing agent, and 1-2 parts of anti-settling agent.

5. The self-healing drainage pavement structure for concrete bridge decks according to claim 1, characterized in that, The wet bonding resin layer comprises the following components by weight: 65-70 parts epoxy resin, 12-16 parts polyamide curing agent, 5-10 parts polyisocyanate adhesive, 2-5 parts polyether resin active toughening agent, and 2-5 parts water-based quartz powder reinforcing agent.

6. The construction method of the self-healing drainage pavement structure for concrete bridge decks as described in any one of claims 1 to 5, characterized in that, The following steps are included: S1. Milling treatment of cement concrete slab base; S2. Spray the material of the wet bonding resin layer onto the cement concrete slab substrate to form a wet bonding resin layer; S3. The material of the self-healing porous concrete pavement layer is laid on the wet bonding resin layer to form a self-healing porous concrete pavement layer. S4. After removing debris from the surface of the self-healing porous concrete pavement, apply the material of the high-temperature reactive adhesive layer evenly to its surface to form a high-temperature reactive adhesive layer. S5. A self-healing PA10 paving layer is laid on the surface of the high-temperature reactive adhesive layer to form a self-healing PA10 paving layer.

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