Roof waterproof protection layer construction method based on microbial concrete

Abstract

The invention belongs to the field of roof waterproof protection layers, and particularly discloses a roof waterproof protection layer construction method based on microbial concrete, which comprises the following specific steps: S1, microbial culture; s2, protective carrier wrapping; s3, preparing concrete; s4, concrete pouring; s5, concrete curing; according to the invention, expanded perlite particles are used as a carrier medium to respectively immobilize individual bacillus and aerobic mixed bacteria, so that the expanded perlite particles are activated and induced to form a composite mineralized structure when cracks are formed, the crack repairing effect is enhanced, and the high strength of aragonite and the good filling property of calcite are combined, so that the crack repairing effect is improved. According to the present invention, the expanded perlite particles are adopted as the carrier medium, and are combined with the hydrogel wrapping the surface of the bacteria-containing expanded perlite, such that the microorganism can be protected, the water storage agent can be used as the water storage agent, and the living environment of the microorganism can be enhanced.

Description

Technical Field

[0001] The invention belongs to the field of roof waterproof protective layers, and in particular relates to a construction method of a roof waterproof protective layer based on microbial concrete. Background Art

[0002] Roof waterproofing is a vital part of building design and construction, which aims to prevent rainwater penetration and moisture accumulation, thereby protecting the structure and interior space of the building. After the roof waterproofing material is laid, it is usually necessary to pour a layer of concrete on the waterproofing material as a roof waterproofing protective layer to protect the waterproofing layer from the external environment and physical damage;

[0003] However, traditional roof waterproofing protective layers usually use ordinary concrete, which is brittle and has low tensile strength, making it easy for concrete to crack, thereby providing channels for moisture, corrosive particles and other substances, reducing the protective effect and causing damage to the roof waterproofing layer, affecting the waterproofing effect.

[0004] After searching, there are related patents disclosed, specifically the invention patent 201910540591.4, the patent name is the method of repairing concrete cracks by adding expanded perlite with immobilized microorganisms, and the publication date is September 27, 2019. It specifically discloses a method of repairing concrete cracks by adding expanded perlite with immobilized microorganisms. The method first uses the vacuum impregnation method to adsorb the mineralized microorganism Bacillus cohnii DSM6307 bacterial suspension and calcium lactate on the surface and internal pores of expanded perlite particles under negative pressure, and then sprays the yeast extract solution on the surface to obtain expanded perlite with immobilized bacteria and calcium lactate, and then evenly sprays the slurry formed by mixing metakaolin, sodium silicate and water to obtain self-repairing particles. After pre-wetting treatment, it is added to concrete for mixing, and standard curing is performed to obtain self-repairing concrete. Another invention patent 202311801204.0, the patent name is a concrete crack self-repairing agent particle and its preparation method and application, the publication date is March 26, 2024, and specifically discloses a method for preparing a concrete crack self-repairing agent particle, including the following steps: activating and culturing the freeze-dried powder of Bacillus pasteurianus and preparing a spore suspension; mixing the expanded perlite with the spore suspension under a vacuum degree of -0.06MPa to obtain the bacteria-carrying perlite; drying; spraying the prepared nutrient solution on the surface of the bacteria-carrying perlite; putting the dried bacteria-carrying perlite into a mixer, and then pouring the prepared potassium magnesium phosphate cement mixture into the mixer, turning on the mixer, so that the potassium magnesium phosphate cement mixture is evenly wrapped on the surface of the bacteria-carrying perlite to form particles; after wrapping, the particles are placed in a container for curing and curing for 1 day, and finally placed in a 40°C blast drying oven and dried to constant weight. The shortcomings of these two patents are that the overall strength and durability of the concrete repair area are not enough, the activity of the microorganisms is poor, and the repair effect is not enough. Summary of the invention

[0005] 1. Technical problem to be solved by the invention

[0006] The purpose of the present invention is to overcome the properties of the existing roof waterproof protective layer, which is brittle and has low tensile strength, making the concrete easy to crack, thereby providing a channel for substances such as moisture and corrosive particles, reducing the protective effect, causing the roof waterproof layer to be damaged and affecting the waterproof effect, and other problems. A construction method for a roof waterproof protective layer based on microbial concrete is provided; the present invention uses expanded perlite particles as a carrier medium, optimizes the bacterial species, and respectively fixes a single Bacillus and an aerobic mixed bacteria, so that they are activated at the same time when cracks are formed, and induce the formation of a composite mineralized structure, thereby enhancing the crack repair effect, and can improve the overall strength and durability of the crack repair area, and visually increase the aesthetics of the concrete repair area.

[0007] 2. Technical solution

[0008] In order to achieve the above object, the technical solution provided by the present invention is:

[0009] A construction method for a roof waterproof protective layer based on microbial concrete, the specific steps are as follows:

[0010] S1. Microbial culture: using liquid culture medium to culture mixed Bacillus, and using culture fluid to culture aerobic mixed bacteria; the mixed Bacillus is one or more of Bacillus sphaericus, Bacillus pasteurianus and Bacillus cohnii.

[0011] S2. Protective carrier encapsulation: Expanded perlite particles P1 are used as microbial carriers, and the obtained mixed Bacillus and aerobic mixed bacteria are adsorbed on the surface and internal gaps of the expanded perlite particles P1 to obtain bacteria-containing expanded perlite particles P2;

[0012] S3, concrete preparation: mixing recycled coarse aggregate, sand and cement to obtain microbial concrete H1;

[0013] S4, concrete pouring: pouring the obtained microbial concrete onto the roof waterproof layer to form a roof waterproof protective layer;

[0014] S5. Concrete maintenance: Maintain the formed roof waterproof protective layer, maintain a moist environment, promote the activity of microorganisms and the solidification of concrete.

[0015] As a further improvement of the present invention, the aerobic mixed bacteria in the S1 step include Bacteroides, Bacillus subtilis and Ureacoccus, in which, according to volume percentage, the Ureacoccus accounts for 15% to 18%, the Bacteroides accounts for 16% to 20%, and the Bacillus subtilis accounts for 32% to 35%.

[0016] As a further improvement of the present invention, the aerobic mixed bacteria in step S1 include Bacillus Pasteurii and alkaliphilic bacteria, wherein the Bacillus Pasteurii accounts for 30% to 50% and the alkaliphilic bacteria accounts for 20% to 40% in terms of volume percentage.

[0017] As a further improvement of the present invention, the specific operation steps of step S2 are:

[0018] S21: Adsorbing the bacterial solution of mixed Bacillus and aerobic mixed bacteria onto the surface and internal voids of the expanded pearlite particles P1 at a pressure of -0.06 MPa by a vacuum impregnation method;

[0019] S22: drying the expanded perlite particles P1 after adsorption to a constant weight at 38-42 degrees Celsius;

[0020] S23: spraying yeast extract solution on the surface of the expanded perlite particles P1;

[0021] S24: Dry the expanded perlite particles P1 again at 38-42 degrees Celsius to constant weight, obtaining a particle size of 2-5 mm and a bulk density of 76-80 kg / m 3 The bacteria-containing expanded perlite particles P2.

[0022] As a further improvement of the present invention, the specific operation steps of step S3 are:

[0023] S31: liquid L obtained by mixing metakaolin, sodium silicate solution and water;

[0024] S32: coating the outer surface of the bacteria-containing expanded perlite particles P2 with liquid L to obtain bacteria-containing expanded perlite particles P21;

[0025] S33: mixing recycled coarse aggregate, sand and cement;

[0026] S34: Add the bacteria-containing expanded perlite particles P21 in the final stage of mixing, and obtain the microbial concrete H1 after mixing.

[0027] As a further improvement of the present invention, in the step S2, the bacteria-containing expanded perlite particles P2 and the hydrogel are uniformly mixed in a ratio of 3:1, so that the hydrogel uniformly wraps the outside of the bacteria-containing expanded perlite particles P2.

[0028] As a further improvement of the present invention, the steps for preparing the recycled coarse aggregate in step S33 are as follows:

[0029] S331: mixing the coarse aggregate raw material with the aerobic mixed bacteria to make the microorganisms evenly distributed on the coarse aggregate raw material;

[0030] S332: Soaking the mixed coarse aggregate raw materials in a nutrient solution for mineralization, wherein the mineralization temperature is controlled to be 25 degrees Celsius to 30 degrees Celsius;

[0031] S333: After 3 to 5 days of mineralization, recycled coarse aggregate is obtained.

[0032] As a further improvement of the present invention, in the process of mixing the recycled coarse aggregate, sand and cement, the step S33 adds calcium lactate and polymer emulsion, and then adds a water reducing agent and a water retaining agent. The amount of the water reducing agent added is 0.5% to 2% of the weight of the cement, and the amount of the water retaining agent added is 1% to 3% of the weight of the cement.

[0033] As a further improvement of the present invention, in the step S33, during the mixing of recycled coarse aggregate, sand and cement, a mixture of calcium precipitating bacteria, silicate bacteria and urea is added, wherein the amount of urea added is 0.5% to 2% of the amount of cement, the temperature during the mixing process does not exceed 30 degrees Celsius, the mixing time is 3 to 5 minutes, and a low shear mixing method is adopted, which refers to the use of a lower stirring speed and a gentle stirring method to avoid damage or destruction to the microorganisms in the mixture. .

[0034] 3. Beneficial effects

[0035] The technical solution provided by the present invention has the following beneficial effects compared with the prior art: the present invention uses expanded perlite particles as carrier media to respectively immobilize a single Bacillus and an aerobic mixed bacteria, so that they are activated simultaneously when cracks are formed, and induce the formation of a composite mineralized structure, thereby enhancing the repair effect of the cracks. Aragonite and calcite are formed after mineralization. The high strength of aragonite and the good filling property of calcite are combined to improve the overall strength and durability of the crack repair area, thereby visually increasing the aesthetics of the concrete repair area.

[0036] The present invention uses expanded perlite particles as a carrier medium to protect microorganisms, avoid inactivation during concrete mixing, and ensure the activity of microorganisms. Combined with the hydrogel wrapped on the surface of the bacteria-containing expanded perlite, it can not only protect the microorganisms but also be used as a water storage agent, increase the crack filling amount and reduce water permeability, enhance the living environment of microorganisms, provide water and nutrition for microorganisms, maintain the activity of microorganisms, and thus improve the crack repair effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying creative labor.

[0038] in:

[0039] Figure 1 It is a flowchart of the preparation steps of the present invention;

[0040] Figure 2 It is a composition diagram of the microbial concrete of the present invention;

[0041] Figure 3 This is a block diagram of an aerobic mixed bacteria composition of the present invention;

[0042] Figure 4 This is another aerobic mixed bacteria composition block diagram of the present invention;

[0043] Figure 5 A microscopic schematic diagram of aerobic mixed bacteria-induced precipitation of mineral crystals at cracks of the present invention;

[0044] Figure 6 This is a microscopic schematic diagram of the Bacillus sp. inducing precipitation of mineral crystals at cracks of the present invention. DETAILED DESCRIPTION DETAILED DESCRIPTION

[0046] In order to further understand the content of the present invention, the present invention is described in detail in conjunction with the accompanying drawings and embodiments.

[0047] Example 1

[0048] As attached Figure 1 , Figure 2 and attached Figure 3 As shown, this embodiment provides a method for constructing a roof waterproof protective layer based on microbial concrete, and the specific steps are as follows:

[0049] S1. Microbial culture: using liquid culture medium to culture mixed Bacillus, using culture fluid to culture aerobic mixed bacteria; the mixed Bacillus is spherical Bacillus, pasteurian Bacillus and coheni Bacillus.

[0050] S2. Protective carrier encapsulation: Expanded perlite particles P1 are used as microbial carriers, and the obtained mixed Bacillus and aerobic mixed bacteria are adsorbed on the surface and internal gaps of the expanded perlite particles P1 to obtain bacteria-containing expanded perlite particles P2;

[0051] S3, concrete preparation: mixing recycled coarse aggregate, sand and cement to obtain microbial concrete H1;

[0052] S4, concrete pouring: pouring the obtained microbial concrete onto the roof waterproof layer to form a roof waterproof protective layer;

[0053] S5. Concrete maintenance: Maintain the formed roof waterproof protective layer, maintain a moist environment, promote the activity of microorganisms and the solidification of concrete.

[0054] Preferably, the aerobic mixed bacteria in step S1 include Bacteroides, Bacillus subtilis and Ureacoccus, wherein, in terms of volume percentage, Ureacoccus accounts for 15%, the Bacteroides accounts for 16%, and the Bacillus subtilis accounts for 32%.

[0055] Preferably, the specific operation steps of step S2 are:

[0056] S21: Adsorbing the bacterial solution of mixed Bacillus and aerobic mixed bacteria onto the surface and internal voids of the expanded pearlite particles P1 at a pressure of -0.06 MPa by a vacuum impregnation method;

[0057] S22: drying the expanded perlite particles P1 after adsorption at 38 degrees Celsius to a constant weight;

[0058] S23: spraying yeast extract solution on the surface of the expanded perlite particles P1;

[0059] S24: Dry the expanded perlite particles P1 again at 38 degrees Celsius to constant weight, obtaining a particle size of 2 mm and a bulk density of 76 kg / m 3 The bacteria-containing expanded perlite particles P2.

[0060] Preferably, the specific operation steps of step S3 are:

[0061] S31: liquid L obtained by mixing metakaolin, sodium silicate solution and water;

[0062] S32: coating the outer surface of the bacteria-containing expanded perlite particles P2 with liquid L to obtain bacteria-containing expanded perlite particles P21;

[0063] S33: mixing recycled coarse aggregate, sand and cement;

[0064] S34: Add the bacteria-containing expanded perlite particles P21 in the final stage of mixing, and obtain the microbial concrete H1 after mixing.

[0065] From the above, it can be seen that by using expanded perlite as a carrier of microorganisms and adsorbing microorganisms on the surface and internal gaps of expanded perlite particles by vacuum impregnation, sufficient living space can be provided for the survival of microorganisms, and microorganisms can be protected from the high alkaline environment of concrete, avoiding the inactivation of microorganisms during the concrete mixing process. At the same time, the surface of the expanded perlite particles is externally wrapped to reduce the water absorption rate of the expanded perlite particles, avoiding the diffusion of microorganisms to other parts during the preparation of concrete or the rupture of expanded perlite particles during the mixing of concrete, which leads to the outflow and inactivation of microorganisms. Bacillus and aerobic bacteria are added to the concrete respectively. When cracks appear in the concrete, water and air enter the cracks to activate the dormant Bacillus microorganisms. The microbial metabolism produces mineral precipitation to fill the cracks and achieve self-repair. The aerobic bacteria contain a variety of microorganisms. Ureacoccus has mineralization and deposition function. Although it accounts for a relatively large proportion The content of inorganic carbon in concrete is small, but its inorganic carbon conversion rate is high. Bacteroides plays an important role in the transfer of electrons in the solution under high alkaline environment. Bacillus subtilis has strong vitality and can survive in high temperature, high pressure, high alkali and dry environment. This provides a guarantee for the microorganisms to remain active in the complex environment inside the concrete. The synergistic work between microorganisms in the aerobic flora promotes the formation of CaCO3. When cracks appear in the concrete, the aerobic mixed bacteria and Bacillus will be activated at the same time, and then mineral precipitation will be produced to repair the cracks. The aerobic mixed bacteria will induce the precipitation of calcium carbonate precipitation in the form of aragonite crystals in the cracks, and the Bacillus will induce the precipitation of calcium carbonate precipitation in the form of calcite crystals in the cracks, thereby forming a complex mineralized structure to enhance the repair effect of the cracks. The high strength of aragonite and the good filling property of calcite can be combined to improve the overall strength and durability of the crack repair area, and visually increase the aesthetics of the concrete repair area.

[0066] The elongated crystal morphology of aragonite induced by aerobic mixed bacteria can form better mechanical locking in the cracks and quickly complete the crack repair. Then, the rhombic crystals of calcite induced by Bacillus can fill the crack gaps, enhance adhesion, reduce the penetration of water and other corrosive substances, and improve the repair effect.

[0067] Example 2

[0068] As attached Figure 1 , Figure 2 and attached Figure 3 As shown, this embodiment provides a method for constructing a roof waterproof protective layer based on microbial concrete, and the specific steps are as follows:

[0069] S1. Microbial culture: a liquid culture medium is used to culture mixed Bacillus, and a culture fluid is used to culture aerobic mixed bacteria; the mixed Bacillus is Bacillus cohnii.

[0070] S2. Protective carrier encapsulation: Expanded perlite particles P1 are used as microbial carriers, and the obtained mixed Bacillus and aerobic mixed bacteria are adsorbed on the surface and internal gaps of the expanded perlite particles P1 to obtain bacteria-containing expanded perlite particles P2;

[0071] S3, concrete preparation: mixing recycled coarse aggregate, sand and cement to obtain microbial concrete H1;

[0072] S4, concrete pouring: pouring the obtained microbial concrete onto the roof waterproof layer to form a roof waterproof protective layer;

[0073] S5. Concrete maintenance: Maintain the formed roof waterproof protective layer, maintain a moist environment, promote the activity of microorganisms and the solidification of concrete.

[0074] Preferably, the aerobic mixed bacteria in step S1 include Bacteroides, Bacillus subtilis and Ureacoccus, wherein, in terms of volume percentage, Ureacoccus accounts for 18%, Bacteroides accounts for 20%, and Bacillus subtilis accounts for 35%.

[0075] Preferably, the specific operation steps of step S2 are:

[0076] S21: Adsorbing the bacterial solution of mixed Bacillus and aerobic mixed bacteria onto the surface and internal voids of the expanded pearlite particles P1 at a pressure of -0.06 MPa by a vacuum impregnation method;

[0077] S22: drying the expanded perlite particles P1 after adsorption at 42 degrees Celsius to a constant weight;

[0078] S23: spraying yeast extract solution on the surface of the expanded perlite particles P1;

[0079] S24: Dry the expanded perlite particles P1 again at 42 degrees Celsius to constant weight, obtaining a particle size of 5 mm and a bulk density of 80 kg / m 3 The bacteria-containing expanded perlite particles P2.

[0080] Preferably, the specific operation steps of step S3 are:

[0081] S31: liquid L obtained by mixing metakaolin, sodium silicate solution and water;

[0082] S32: coating the outer surface of the bacteria-containing expanded perlite particles P2 with liquid L to obtain bacteria-containing expanded perlite particles P21;

[0083] S33: mixing recycled coarse aggregate, sand and cement;

[0084] S34: Add the bacteria-containing expanded perlite particles P21 in the final stage of mixing, and obtain the microbial concrete H1 after mixing.

[0085] From the above, it can be seen that by using expanded perlite as a carrier of microorganisms and adsorbing microorganisms on the surface and internal gaps of expanded perlite particles by vacuum impregnation, sufficient living space can be provided for the survival of microorganisms, and microorganisms can be protected from the high alkaline environment of concrete, avoiding the inactivation of microorganisms during the concrete mixing process. At the same time, the surface of the expanded perlite particles is externally wrapped to reduce the water absorption rate of the expanded perlite particles, avoiding the diffusion of microorganisms to other parts during the preparation of concrete or the rupture of expanded perlite particles during the mixing of concrete, which leads to the outflow and inactivation of microorganisms. Bacillus and aerobic bacteria are added to the concrete respectively. When cracks appear in the concrete, water and air enter the cracks to activate the dormant Bacillus microorganisms. The microbial metabolism produces mineral precipitation to fill the cracks and achieve self-repair. The aerobic bacteria contain a variety of microorganisms. Ureacoccus has mineralization and deposition function. Although it accounts for a relatively large proportion The content of inorganic carbon in concrete is small, but its inorganic carbon conversion rate is high. Bacteroides plays an important role in the transfer of electrons in the solution under high alkaline environment. Bacillus subtilis has strong vitality and can survive in high temperature, high pressure, high alkali and dry environment. This provides a guarantee for the microorganisms to remain active in the complex environment inside the concrete. The synergistic work between microorganisms in the aerobic flora promotes the formation of CaCO3. When cracks appear in the concrete, the aerobic mixed bacteria and Bacillus will be activated at the same time, and then mineral precipitation will be produced to repair the cracks. The aerobic mixed bacteria will induce the precipitation of calcium carbonate precipitation in the form of aragonite crystals in the cracks, and the Bacillus will induce the precipitation of calcium carbonate precipitation in the form of calcite crystals in the cracks, thereby forming a complex mineralized structure to enhance the repair effect of the cracks. The high strength of aragonite and the good filling property of calcite can be combined to improve the overall strength and durability of the crack repair area, and visually increase the aesthetics of the concrete repair area.

[0086] The elongated crystal morphology of aragonite induced by aerobic mixed bacteria can form better mechanical locking in the cracks and quickly complete the crack repair. Then, the rhombic crystals of calcite induced by Bacillus can fill the crack gaps, enhance adhesion, reduce the penetration of water and other corrosive substances, and improve the repair effect.

[0087] Example 3

[0088] As attached Figure 1 , Figure 2 and attached Figure 4 As shown, this embodiment provides a method for constructing a roof waterproof protective layer based on microbial concrete, and the specific steps are as follows:

[0089] S1. Microbial culture: a liquid culture medium is used to culture mixed Bacillus, and a culture fluid is used to culture aerobic mixed bacteria; the mixed Bacillus includes Bacillus sphaericus, Bacillus pasteurianus and Bacillus cohnii.

[0090] S2. Protective carrier encapsulation: Expanded perlite particles P1 are used as microbial carriers, and the obtained mixed Bacillus and aerobic mixed bacteria are adsorbed on the surface and internal gaps of the expanded perlite particles P1 to obtain bacteria-containing expanded perlite particles P2;

[0091] S3, concrete preparation: mixing recycled coarse aggregate, sand and cement to obtain microbial concrete H1;

[0092] S4, concrete pouring: pouring the obtained microbial concrete onto the roof waterproof layer to form a roof waterproof protective layer;

[0093] S5. Concrete maintenance: Maintain the formed roof waterproof protective layer, maintain a moist environment, promote the activity of microorganisms and the solidification of concrete.

[0094] Preferably, the aerobic mixed bacteria in step S1 include Bacillus Pasteurellii and alkaliphilic bacteria, wherein the Bacillus Pasteurellii accounts for 30% and the alkaliphilic bacteria accounts for 20% in terms of volume percentage.

[0095] Preferably, the specific operation steps of step S2 are:

[0096] S21: Adsorbing the bacterial solution of mixed Bacillus and aerobic mixed bacteria onto the surface and internal voids of the expanded pearlite particles P1 at a pressure of -0.06 MPa by a vacuum impregnation method;

[0097] S22: drying the expanded perlite particles P1 after adsorption at 38 degrees Celsius to a constant weight;

[0098] S23: spraying yeast extract solution on the surface of the expanded perlite particles P1;

[0099] S24: Dry the expanded perlite particles P1 again at 38-42 degrees Celsius to constant weight, obtaining a particle size of 2 mm and a bulk density of 76 kg / m 3 The bacteria-containing expanded perlite particles P2.

[0100] Preferably, the specific operation steps of step S3 are:

[0101] S31: liquid L obtained by mixing metakaolin, sodium silicate solution and water;

[0102] S32: coating the outer surface of the bacteria-containing expanded perlite particles P2 with liquid L to obtain bacteria-containing expanded perlite particles P21;

[0103] S33: mixing recycled coarse aggregate, sand and cement;

[0104] S34: Add the bacteria-containing expanded perlite particles P21 in the final stage of mixing, and obtain the microbial concrete H1 after mixing.

[0105] From the above, it can be seen that by using expanded perlite as a carrier of microorganisms and adsorbing microorganisms on the surface and internal gaps of expanded perlite particles by vacuum impregnation, sufficient living space can be provided for the survival of microorganisms, and microorganisms can be protected from the high alkaline environment of concrete, avoiding the inactivation of microorganisms during the concrete mixing process. At the same time, the surface of the expanded perlite particles is externally wrapped to reduce the water absorption rate of the expanded perlite particles, avoiding the diffusion of microorganisms to other parts during the preparation of concrete or the rupture of expanded perlite particles during the mixing of concrete, which leads to the outflow and inactivation of microorganisms. Bacillus and aerobic bacteria are added to the concrete respectively. When cracks appear in the concrete, water and air enter the cracks to activate the dormant Bacillus microorganisms. The microbial metabolism produces mineral precipitation to fill the cracks and achieve self-repair. The aerobic bacteria contain a variety of microorganisms. Ureacoccus has mineralization and deposition function. Although it accounts for a relatively large proportion The content of inorganic carbon in concrete is small, but its inorganic carbon conversion rate is high. Bacteroides plays an important role in the transfer of electrons in the solution under high alkaline environment. Bacillus subtilis has strong vitality and can survive in high temperature, high pressure, high alkali and dry environment. This provides a guarantee for the microorganisms to remain active in the complex environment inside the concrete. The synergistic work between microorganisms in the aerobic flora promotes the formation of CaCO3. When cracks appear in the concrete, the aerobic mixed bacteria and Bacillus will be activated at the same time, and then mineral precipitation will be produced to repair the cracks. The aerobic mixed bacteria will induce the precipitation of calcium carbonate precipitation in the form of aragonite crystals in the cracks, and the Bacillus will induce the precipitation of calcium carbonate precipitation in the form of calcite crystals in the cracks, thereby forming a complex mineralized structure to enhance the repair effect of the cracks. The high strength of aragonite and the good filling property of calcite can be combined to improve the overall strength and durability of the crack repair area, and visually increase the aesthetics of the concrete repair area.

[0106] The elongated crystal morphology of aragonite induced by aerobic mixed bacteria can form better mechanical locking in the cracks and quickly complete the crack repair. Then, the rhombic crystals of calcite induced by Bacillus can fill the crack gaps, enhance adhesion, reduce the penetration of water and other corrosive substances, and improve the repair effect.

[0107] Example 4

[0108] As attached Figure 1 , Figure 2 and attached Figure 4As shown, this embodiment provides a method for constructing a roof waterproof protective layer based on microbial concrete, and the specific steps are as follows:

[0109] S1. Microbial culture: using liquid culture medium to culture to obtain mixed Bacillus, and using culture fluid to culture to obtain aerobic mixed bacteria; the mixed Bacillus are Bacillus pasteurianus and Bacillus cohnii.

[0110] S2. Protective carrier encapsulation: Expanded perlite particles P1 are used as microbial carriers, and the obtained mixed Bacillus and aerobic mixed bacteria are adsorbed on the surface and internal gaps of the expanded perlite particles P1 to obtain bacteria-containing expanded perlite particles P2;

[0111] S3, concrete preparation: mixing recycled coarse aggregate, sand and cement to obtain microbial concrete H1;

[0112] S4, concrete pouring: pouring the obtained microbial concrete onto the roof waterproof layer to form a roof waterproof protective layer;

[0113] S5. Concrete maintenance: Maintain the formed roof waterproof protective layer, maintain a moist environment, promote the activity of microorganisms and the solidification of concrete.

[0114] Preferably, the aerobic mixed bacteria in step S1 include Bacillus Pasteurii and alkaliphilic bacteria, wherein the Bacillus Pasteurii accounts for 50% and the alkaliphilic bacteria accounts for 40% in terms of volume percentage.

[0115] Preferably, the specific operation steps of step S2 are:

[0116] S21: Adsorbing the bacterial solution of mixed Bacillus and aerobic mixed bacteria onto the surface and internal voids of the expanded pearlite particles P1 at a pressure of -0.06 MPa by a vacuum impregnation method;

[0117] S22: drying the expanded perlite particles P1 after adsorption at 42 degrees Celsius to a constant weight;

[0118] S23: spraying yeast extract solution on the surface of the expanded perlite particles P1;

[0119] S24: Dry the expanded perlite particles P1 again at 38-42 degrees Celsius to constant weight, obtaining a particle size of 5 mm and a bulk density of 80 kg / m 3 The bacteria-containing expanded perlite particles P2.

[0120] Preferably, the specific operation steps of step S3 are:

[0121] S31: liquid L obtained by mixing metakaolin, sodium silicate solution and water;

[0122] S32: coating the outer surface of the bacteria-containing expanded perlite particles P2 with liquid L to obtain bacteria-containing expanded perlite particles P21;

[0123] S33: mixing recycled coarse aggregate, sand and cement;

[0124] S34: Add the bacteria-containing expanded perlite particles P21 in the final stage of mixing, and obtain the microbial concrete H1 after mixing.

[0125] From the above, it can be seen that by using expanded perlite as a carrier of microorganisms and adsorbing microorganisms on the surface and internal gaps of expanded perlite particles by vacuum impregnation, sufficient living space can be provided for the survival of microorganisms, and microorganisms can be protected from the high alkaline environment of concrete, avoiding the inactivation of microorganisms during the concrete mixing process. At the same time, the surface of the expanded perlite particles is externally wrapped to reduce the water absorption rate of the expanded perlite particles, avoiding the diffusion of microorganisms to other parts during the preparation of concrete or the rupture of expanded perlite particles during the mixing of concrete, which leads to the outflow and inactivation of microorganisms. Bacillus and aerobic bacteria are added to the concrete respectively. When cracks appear in the concrete, water and air enter the cracks to activate the dormant Bacillus microorganisms. The microbial metabolism produces mineral precipitation to fill the cracks and achieve self-repair. The aerobic bacteria contain a variety of microorganisms. Ureacoccus has mineralization and deposition function. Although it accounts for a relatively large proportion The content of inorganic carbon in concrete is small, but its inorganic carbon conversion rate is high. Bacteroides plays an important role in the transfer of electrons in the solution under high alkaline environment. Bacillus subtilis has strong vitality and can survive in high temperature, high pressure, high alkali and dry environment. This provides a guarantee for the microorganisms to remain active in the complex environment inside the concrete. The synergistic work between microorganisms in the aerobic flora promotes the formation of CaCO3. When cracks appear in the concrete, the aerobic mixed bacteria and Bacillus will be activated at the same time, and then mineral precipitation will be produced to repair the cracks. The aerobic mixed bacteria will induce the precipitation of calcium carbonate precipitation in the form of aragonite crystals in the cracks, and the Bacillus will induce the precipitation of calcium carbonate precipitation in the form of calcite crystals in the cracks, thereby forming a complex mineralized structure to enhance the repair effect of the cracks. The high strength of aragonite and the good filling property of calcite can be combined to improve the overall strength and durability of the crack repair area, and visually increase the aesthetics of the concrete repair area.

[0126] The elongated crystal morphology of aragonite induced by aerobic mixed bacteria can form better mechanical locking in the cracks and quickly complete the crack repair. Then, the rhombic crystals of calcite induced by Bacillus can fill the crack gaps, enhance adhesion, reduce the penetration of water and other corrosive substances, and improve the repair effect.

[0127] Example 5

[0128] As attached Figure 1 To Attachment Figure 4 As shown, this embodiment provides a method for constructing a roof waterproof protective layer based on microbial concrete, and the specific steps are as follows:

[0129] S1. Microbial culture: a liquid culture medium is used to culture mixed Bacillus, and a culture fluid is used to culture aerobic mixed bacteria; the mixed Bacillus includes Bacillus sphaericus, Bacillus pasteurianus and Bacillus cohnii.

[0130] S2. Protective carrier encapsulation: Expanded perlite particles P1 are used as microbial carriers, and the obtained mixed Bacillus and aerobic mixed bacteria are adsorbed on the surface and internal gaps of the expanded perlite particles P1 to obtain bacteria-containing expanded perlite particles P2;

[0131] S3, concrete preparation: mixing recycled coarse aggregate, sand and cement to obtain microbial concrete H1;

[0132] S4, concrete pouring: pouring the obtained microbial concrete onto the roof waterproof layer to form a roof waterproof protective layer;

[0133] S5. Concrete maintenance: Maintain the formed roof waterproof protective layer, maintain a moist environment, promote the activity of microorganisms and the solidification of concrete.

[0134] Preferably, the aerobic mixed bacteria in step S1 include Bacteroides, Bacillus subtilis and Ureacoccus, wherein, in terms of volume percentage, Ureacoccus accounts for 15%, the Bacteroides accounts for 16%, and the Bacillus subtilis accounts for 32%.

[0135] Preferably, the aerobic mixed bacteria in step S1 include Bacillus Pasteurii and alkaliphilic bacteria, wherein the Bacillus Pasteurii accounts for 30% and the alkaliphilic bacteria accounts for 20% in terms of volume percentage.

[0136] Preferably, the specific operation steps of step S2 are:

[0137] S21: Adsorbing the bacterial solution of mixed Bacillus and aerobic mixed bacteria onto the surface and internal voids of the expanded pearlite particles P1 at a pressure of -0.06 MPa by a vacuum impregnation method;

[0138] S22: drying the expanded perlite particles P1 after adsorption at 38 degrees Celsius to a constant weight;

[0139] S23: spraying yeast extract solution on the surface of the expanded perlite particles P1;

[0140] S24: Dry the expanded perlite particles P1 again at 38 degrees Celsius to constant weight, obtaining a particle size of 2 mm and a bulk density of 76 kg / m3 The bacteria-containing expanded perlite particles P2.

[0141] Preferably, the specific operation steps of step S3 are:

[0142] S31: liquid L obtained by mixing metakaolin, sodium silicate solution and water;

[0143] S32: coating the outer surface of the bacteria-containing expanded perlite particles P2 with liquid L to obtain bacteria-containing expanded perlite particles P21;

[0144] S33: mixing recycled coarse aggregate, sand and cement;

[0145] S34: Add the bacteria-containing expanded perlite particles P21 in the final stage of mixing, and obtain the microbial concrete H1 after mixing.

[0146] Preferably, the steps for preparing the recycled coarse aggregate in step S33 are as follows:

[0147] S331: mixing the coarse aggregate raw material with the aerobic mixed bacteria to make the microorganisms evenly distributed on the coarse aggregate raw material;

[0148] S332: Soaking the mixed coarse aggregate raw materials in a nutrient solution for mineralization, wherein the mineralization temperature is controlled at 25 degrees Celsius; the nutrient solution is an aqueous solution containing urea, phosphate, potassium chloride, iron and zinc.

[0149] S333: After 3 days of mineralization, recycled coarse aggregate is obtained.

[0150] In this embodiment, aerobic alkaliphilic mixed bacteria are cultivated and mixed with recycled coarse aggregate, and then immersed in a nutrient solution for mineralization treatment. The recycled coarse aggregate can be pretreated before being mixed with cement to prepare concrete, and the voids and cracks of the recycled coarse aggregate itself can be repaired to enhance the physical and mechanical properties of the recycled aggregate. The mixed bacteria can be effectively fixed to become a microbial carrier medium, and after being subsequently mixed with cement to form concrete, the cracks in the weak bonding area between the recycled aggregate and the cement stone matrix can be self-repaired, and at the same time, the self-repairing ability and efficiency of the concrete when cracks appear on the subsequent surface can be improved.

[0151] Example 6

[0152] As attached Figure 1 To Attachment Figure 4 As shown, this embodiment provides a method for constructing a roof waterproof protective layer based on microbial concrete, and the specific steps are as follows:

[0153] S1. Microbial culture: a liquid culture medium is used to culture mixed Bacillus, and a culture fluid is used to culture aerobic mixed bacteria; the mixed Bacillus includes Bacillus sphaericus, Bacillus pasteurianus and Bacillus cohnii.

[0154] S2. Protective carrier encapsulation: Expanded perlite particles P1 are used as microbial carriers, and the obtained mixed Bacillus and aerobic mixed bacteria are adsorbed on the surface and internal gaps of the expanded perlite particles P1 to obtain bacteria-containing expanded perlite particles P2;

[0155] S3, concrete preparation: mixing recycled coarse aggregate, sand and cement to obtain microbial concrete H1;

[0156] S4, concrete pouring: pouring the obtained microbial concrete onto the roof waterproof layer to form a roof waterproof protective layer;

[0157] S5. Concrete maintenance: Maintain the formed roof waterproof protective layer, maintain a moist environment, promote the activity of microorganisms and the solidification of concrete.

[0158] Preferably, the aerobic mixed bacteria in step S1 include Bacteroides, Bacillus subtilis and Ureacoccus, wherein, in terms of volume percentage, Ureacoccus accounts for 18%, Bacteroides accounts for 20%, and Bacillus subtilis accounts for 35%.

[0159] Preferably, the aerobic mixed bacteria in step S1 include Bacillus Pasteurii and alkaliphilic bacteria, wherein the Bacillus Pasteurii accounts for 50% and the alkaliphilic bacteria accounts for 40% in terms of volume percentage.

[0160] Preferably, the specific operation steps of step S2 are:

[0161] S21: Adsorbing the bacterial solution of mixed Bacillus and aerobic mixed bacteria onto the surface and internal voids of the expanded pearlite particles P1 at a pressure of -0.06 MPa by a vacuum impregnation method;

[0162] S22: drying the expanded perlite particles P1 after adsorption at 42 degrees Celsius to a constant weight;

[0163] S23: spraying yeast extract solution on the surface of the expanded perlite particles P1;

[0164] S24: Dry the expanded perlite particles P1 again at 38-42 degrees Celsius to constant weight, obtaining a particle size of 5 mm and a bulk density of 80 kg / m 3 The bacteria-containing expanded perlite particles P2.

[0165] Preferably, the specific operation steps of step S3 are:

[0166] S31: liquid L obtained by mixing metakaolin, sodium silicate solution and water;

[0167] S32: coating the outer surface of the bacteria-containing expanded perlite particles P2 with liquid L to obtain bacteria-containing expanded perlite particles P21;

[0168] S33: mixing recycled coarse aggregate, sand and cement;

[0169] S34: Add the bacteria-containing expanded perlite particles P21 in the final stage of mixing, and obtain the microbial concrete H1 after mixing.

[0170] Preferably, the steps for preparing the recycled coarse aggregate in step S33 are as follows:

[0171] S331: mixing the coarse aggregate raw material with the aerobic mixed bacteria to make the microorganisms evenly distributed on the coarse aggregate raw material;

[0172] S332: Soaking the mixed coarse aggregate raw materials in a nutrient solution for mineralization, wherein the mineralization temperature is controlled at 30 degrees Celsius; the nutrient solution is an aqueous solution containing urea, phosphate, potassium chloride, iron and zinc.

[0173] S333: After 5 days of mineralization, recycled coarse aggregate is obtained.

[0174] In this embodiment, aerobic alkaliphilic mixed bacteria are cultivated and mixed with recycled coarse aggregate, and then immersed in a nutrient solution for mineralization treatment. The recycled coarse aggregate can be pretreated before being mixed with cement to prepare concrete, and the voids and cracks of the recycled coarse aggregate itself can be repaired to enhance the physical and mechanical properties of the recycled aggregate. The mixed bacteria can be effectively fixed to become a microbial carrier medium, and after being subsequently mixed with cement to form concrete, the cracks in the weak bonding area between the recycled aggregate and the cement stone matrix can be self-repaired, and at the same time, the self-repairing ability and efficiency of the concrete when cracks appear on the subsequent surface can be improved.

[0175] Embodiment 7:

[0176] As attached Figure 1 To Attachment Figure 6 The present embodiment provides a method for constructing a roof waterproof protective layer based on microbial concrete, and the specific steps are as follows:

[0177] S1. Microbial culture: a liquid culture medium is used to culture mixed Bacillus, and a culture fluid is used to culture aerobic mixed bacteria; the mixed Bacillus includes Bacillus sphaericus, Bacillus pasteurianus and Bacillus cohnii.

[0178] S2. Protective carrier encapsulation: Expanded perlite particles P1 are used as microbial carriers, and the obtained mixed Bacillus and aerobic mixed bacteria are adsorbed on the surface and internal gaps of the expanded perlite particles P1 to obtain bacteria-containing expanded perlite particles P2;

[0179] S3, concrete preparation: mixing recycled coarse aggregate, sand and cement to obtain microbial concrete H1;

[0180] S4, concrete pouring: pouring the obtained microbial concrete onto the roof waterproof layer to form a roof waterproof protective layer;

[0181] S5. Concrete maintenance: Maintain the formed roof waterproof protective layer, maintain a moist environment, promote the activity of microorganisms and the solidification of concrete.

[0182] Preferably, the aerobic mixed bacteria in step S1 include Bacteroides, Bacillus subtilis and Ureacoccus, wherein, in terms of volume percentage, Ureacoccus accounts for 15%, the Bacteroides accounts for 16%, and the Bacillus subtilis accounts for 32%.

[0183] Preferably, the specific operation steps of step S2 are:

[0184] S21: Adsorbing the bacterial solution of mixed Bacillus and aerobic mixed bacteria onto the surface and internal voids of the expanded pearlite particles P1 at a pressure of -0.06 MPa by a vacuum impregnation method;

[0185] S22: drying the expanded perlite particles P1 after adsorption to a constant weight at 38-42 degrees Celsius;

[0186] S23: spraying yeast extract solution on the surface of the expanded perlite particles P1;

[0187] S24: Dry the expanded perlite particles P1 again at 38-42 degrees Celsius to constant weight, obtaining a particle size of 2 mm and a bulk density of 76 kg / m 3 The bacteria-containing expanded perlite particles P2.

[0188] Preferably, the specific operation steps of step S3 are:

[0189] S31: liquid L obtained by mixing metakaolin, sodium silicate solution and water;

[0190] S32: coating the outer surface of the bacteria-containing expanded perlite particles P2 with liquid L to obtain bacteria-containing expanded perlite particles P21;

[0191] S33: mixing recycled coarse aggregate, sand and cement;

[0192] S34: Add the bacteria-containing expanded perlite particles P21 in the final stage of mixing, and obtain the microbial concrete H1 after mixing.

[0193] Preferably, in the step S2, the bacteria-containing expanded perlite particles P2 and the hydrogel are uniformly mixed in a ratio of 3:1, so that the hydrogel uniformly wraps the outside of the bacteria-containing expanded perlite particles P2.

[0194] Preferably, the steps for preparing the recycled coarse aggregate in step S33 are as follows:

[0195] S331: mixing the coarse aggregate raw material with the aerobic mixed bacteria to make the microorganisms evenly distributed on the coarse aggregate raw material;

[0196] S332: Soaking the mixed coarse aggregate raw materials in a nutrient solution for mineralization, wherein the mineralization temperature is controlled at 25 degrees Celsius; the nutrient solution is an aqueous solution containing urea, phosphate, potassium chloride, iron and zinc.

[0197] S333: After 3 days of mineralization, recycled coarse aggregate is obtained.

[0198] Preferably, in the step S33, calcium lactate and polymer emulsion are added during the mixing of recycled coarse aggregate, sand and cement, and then a water reducer and a water retainer are added. The amount of the water reducer added is 0.5% of the weight of the cement, and the amount of the water retainer added is 1% of the weight of the cement. By using a high-efficiency water reducer, the fluidity of the concrete can be improved and the amount of water can be reduced. At the same time, the use of a water retainer, such as a polymer additive, can improve the water retention of the concrete and promote the activity of microorganisms. The polymer emulsion is an aqueous polymer emulsion, which is a polyvinyl alcohol (PVA) emulsion, which is used to improve the toughness and adhesion of the concrete. The amount of calcium lactate added is 1% of the weight of the cement, and the addition ratio of the polymer emulsion is 5% of the weight of the cement.

[0199] Preferably, in the step S33, during the mixing of recycled coarse aggregate, sand and cement, a mixture of calcium precipitating bacteria, silicate bacteria and urea is added, wherein the amount of urea added is 0.5% of the amount of cement, the temperature during the mixing process is 27 degrees Celsius, the mixing time is 3 minutes, and a low shear mixing method is adopted to avoid microbial damage caused by excessive stirring; the amount of calcium precipitating bacteria and silicate bacteria added is 1% of the amount of cement.

[0200] In this embodiment, during the concrete mixing process, a mixed bacteria formed by calcium-precipitating bacteria and silicate bacteria is added with urea as a nutrient matrix, and urea is used as a nitrogen source to promote the growth of microorganisms. The calcium-precipitating bacteria can promote calcium precipitation when cracks are generated, and the silicate bacteria can promote silicate precipitation when cracks are generated, thereby enhancing the strength of the concrete and thus improving the crack repair effect.

[0201] By wrapping hydrogel on the surface of bacteria-containing expanded perlite, hydrogel is a hydrophilic gel with a polymer chain network, which has high water absorption and can retain a large amount of water or aqueous solution. Hydrogel can not only protect microorganisms but also be used as a water storage agent, increase the crack filling amount and reduce water permeability, enhance the living environment of microorganisms, provide water and nutrition for microorganisms, maintain the activity of microorganisms, and thus improve the crack repair effect.

[0202] This design application is applied to roof waterproofing in building construction. Expanded perlite is used as a microbial carrier. Bacillus and aerobic mixed bacteria are mixed into concrete to form microbial concrete. The microbial concrete is then poured onto the roof waterproofing membrane to form a protective layer to complete the construction of roof waterproofing. The purpose is to quickly complete self-repair when cracks appear in the concrete, and to improve the aesthetics and strength of the repaired area.

[0203] Example 8

[0204] As attached Figure 1 To Attachment Figure 6 The present embodiment provides a method for constructing a roof waterproof protective layer based on microbial concrete, and the specific steps are as follows:

[0205] S1. Microbial culture: a liquid culture medium is used to culture mixed Bacillus, and a culture fluid is used to culture aerobic mixed bacteria; the mixed Bacillus includes Bacillus sphaericus, Bacillus pasteurianus and Bacillus cohnii.

[0206] S2. Protective carrier encapsulation: Expanded perlite particles P1 are used as microbial carriers, and the obtained mixed Bacillus and aerobic mixed bacteria are adsorbed on the surface and internal gaps of the expanded perlite particles P1 to obtain bacteria-containing expanded perlite particles P2;

[0207] S3, concrete preparation: mixing recycled coarse aggregate, sand and cement to obtain microbial concrete H1;

[0208] S4, concrete pouring: pouring the obtained microbial concrete onto the roof waterproof layer to form a roof waterproof protective layer;

[0209] S5. Concrete maintenance: Maintain the formed roof waterproof protective layer, maintain a moist environment, promote the activity of microorganisms and the solidification of concrete.

[0210] Preferably, the aerobic mixed bacteria in step S1 include Bacteroides, Bacillus subtilis and Ureacoccus, wherein, in terms of volume percentage, Ureacoccus accounts for 18%, Bacteroides accounts for 20%, and Bacillus subtilis accounts for 35%.

[0211] Preferably, the specific operation steps of step S2 are:

[0212] S21: Adsorbing the bacterial solution of mixed Bacillus and aerobic mixed bacteria onto the surface and internal voids of the expanded pearlite particles P1 at a pressure of -0.06 MPa by a vacuum impregnation method;

[0213] S22: drying the expanded perlite particles P1 after adsorption at 42 degrees Celsius to a constant weight;

[0214] S23: spraying yeast extract solution on the surface of the expanded perlite particles P1;

[0215] S24: Dry the expanded perlite particles P1 again at 42 degrees Celsius to constant weight, obtaining a particle size of 5 mm and a bulk density of 80 kg / m 3 The bacteria-containing expanded perlite particles P2.

[0216] Preferably, the specific operation steps of step S3 are:

[0217] S31: liquid L obtained by mixing metakaolin, sodium silicate solution and water;

[0218] S32: coating the outer surface of the bacteria-containing expanded perlite particles P2 with liquid L to obtain bacteria-containing expanded perlite particles P21;

[0219] S33: mixing recycled coarse aggregate, sand and cement;

[0220] S34: Add the bacteria-containing expanded perlite particles P21 in the final stage of mixing, and obtain the microbial concrete H1 after mixing.

[0221] Preferably, in the step S2, the bacteria-containing expanded perlite particles P2 and the hydrogel are uniformly mixed in a ratio of 3:1, so that the hydrogel uniformly wraps the outside of the bacteria-containing expanded perlite particles P2.

[0222] Preferably, the steps for preparing the recycled coarse aggregate in step S33 are as follows:

[0223] S331: mixing the coarse aggregate raw material with the aerobic mixed bacteria to make the microorganisms evenly distributed on the coarse aggregate raw material;

[0224] S332: Soaking the mixed coarse aggregate raw materials in a nutrient solution for mineralization, wherein the mineralization temperature is controlled at 30 degrees Celsius; the nutrient solution is an aqueous solution containing urea, phosphate, potassium chloride, iron and zinc.

[0225] S333: After 5 days of mineralization, recycled coarse aggregate is obtained.

[0226] Preferably, in the step S33, calcium lactate and polymer emulsion are added during the mixing of recycled coarse aggregate, sand and cement, and then a water reducer and a water retainer are added. The amount of the water reducer added is 2% of the weight of the cement, and the amount of the water retainer added is 3% of the weight of the cement. By using a high-efficiency water reducer, the fluidity of the concrete can be improved and the amount of water can be reduced. At the same time, the use of a water retainer, such as a polymer additive, can improve the water retention of the concrete and promote the activity of microorganisms. The polymer emulsion is an aqueous polymer emulsion, which is a polyvinyl alcohol (PVA) emulsion, which is used to improve the toughness and adhesion of the concrete. The amount of calcium lactate added is 3% of the weight of the cement, and the addition ratio of the polymer emulsion is 15% of the weight of the cement.

[0227] Preferably, in the step S33, during the mixing of recycled coarse aggregate, sand and cement, a mixture of calcium precipitating bacteria, silicate bacteria and urea is added, wherein the amount of urea added is 2% of the amount of cement, the temperature during the mixing process is 30 degrees Celsius, the mixing time is 5 minutes, and a low shear mixing method is adopted to avoid microbial damage caused by excessive stirring; the amount of calcium precipitating bacteria and silicate bacteria added is 5% of the amount of cement.

[0228] In this embodiment, during the concrete mixing process, a mixed bacteria formed by calcium-precipitating bacteria and silicate bacteria is added with urea as a nutrient matrix, and urea is used as a nitrogen source to promote the growth of microorganisms. The calcium-precipitating bacteria can promote calcium precipitation when cracks are generated, and the silicate bacteria can promote silicate precipitation when cracks are generated, thereby enhancing the strength of the concrete and thus improving the crack repair effect.

[0229] By wrapping hydrogel on the surface of bacteria-containing expanded perlite, hydrogel is a hydrophilic gel with a polymer chain network, which has high water absorption and can retain a large amount of water or aqueous solution. Hydrogel can not only protect microorganisms but also be used as a water storage agent, increase the crack filling amount and reduce water permeability, enhance the living environment of microorganisms, provide water and nutrition for microorganisms, maintain the activity of microorganisms, and thus improve the crack repair effect.

[0230] This design application is applied to roof waterproofing in building construction. Expanded perlite is used as a microbial carrier. Bacillus and aerobic mixed bacteria are mixed into concrete to form microbial concrete. The microbial concrete is then poured onto the roof waterproofing membrane to form a protective layer to complete the construction of roof waterproofing. The purpose is to quickly complete self-repair when cracks appear in the concrete, and to improve the aesthetics and strength of the repaired area.

[0231] Example 9

[0232] As attached Figure 1 To Attachment Figure 6 The present embodiment provides a method for constructing a roof waterproof protective layer based on microbial concrete, and the specific steps are as follows:

[0233] S1. Microbial culture: a liquid culture medium is used to culture mixed Bacillus, and a culture fluid is used to culture aerobic mixed bacteria; the mixed Bacillus includes Bacillus sphaericus, Bacillus pasteurianus and Bacillus cohnii.

[0234] S2. Protective carrier encapsulation: Expanded perlite particles P1 are used as microbial carriers, and the obtained mixed Bacillus and aerobic mixed bacteria are adsorbed on the surface and internal gaps of the expanded perlite particles P1 to obtain bacteria-containing expanded perlite particles P2;

[0235] S3, concrete preparation: mixing recycled coarse aggregate, sand and cement to obtain microbial concrete H1;

[0236] S4, concrete pouring: pouring the obtained microbial concrete onto the roof waterproof layer to form a roof waterproof protective layer;

[0237] S5. Concrete maintenance: Maintain the formed roof waterproof protective layer, maintain a moist environment, promote the activity of microorganisms and the solidification of concrete.

[0238] Preferably, the aerobic mixed bacteria in step S1 include Bacillus Pasteurii and alkaliphilic bacteria, wherein the Bacillus Pasteurii accounts for 30% and the alkaliphilic bacteria accounts for 20% in terms of volume percentage.

[0239] Preferably, the specific operation steps of step S2 are:

[0240] S21: Adsorbing the bacterial solution of mixed Bacillus and aerobic mixed bacteria onto the surface and internal voids of the expanded pearlite particles P1 at a pressure of -0.06 MPa by a vacuum impregnation method;

[0241] S22: drying the expanded perlite particles P1 after adsorption at 38 degrees Celsius to a constant weight;

[0242] S23: spraying yeast extract solution on the surface of the expanded perlite particles P1;

[0243] S24: Dry the expanded perlite particles P1 again at 38 degrees Celsius to constant weight, obtaining a particle size of 2 mm and a bulk density of 76 kg / m 3 The bacteria-containing expanded perlite particles P2.

[0244] Preferably, the specific operation steps of step S3 are:

[0245] S31: liquid L obtained by mixing metakaolin, sodium silicate solution and water;

[0246] S32: coating the outer surface of the bacteria-containing expanded perlite particles P2 with liquid L to obtain bacteria-containing expanded perlite particles P21;

[0247] S33: mixing recycled coarse aggregate, sand and cement;

[0248] S34: Add the bacteria-containing expanded perlite particles P21 in the final stage of mixing, and obtain the microbial concrete H1 after mixing.

[0249] Preferably, in the step S2, the bacteria-containing expanded perlite particles P2 and the hydrogel are uniformly mixed in a ratio of 3:1, so that the hydrogel uniformly wraps the outside of the bacteria-containing expanded perlite particles P2.

[0250] Preferably, the steps for preparing the recycled coarse aggregate in step S33 are as follows:

[0251] S331: mixing the coarse aggregate raw material with the aerobic mixed bacteria to make the microorganisms evenly distributed on the coarse aggregate raw material;

[0252] S332: Soaking the mixed coarse aggregate raw materials in a nutrient solution for mineralization, wherein the mineralization temperature is controlled at 25 degrees Celsius; the nutrient solution is an aqueous solution containing urea, phosphate, potassium chloride, iron and zinc.

[0253] S333: After 3 days of mineralization, recycled coarse aggregate is obtained.

[0254] Preferably, in the step S33, calcium lactate and polymer emulsion are added during the mixing of recycled coarse aggregate, sand and cement, and then a water reducer and a water retainer are added. The amount of the water reducer added is 0.5% of the weight of the cement, and the amount of the water retainer added is 1% of the weight of the cement. By using a high-efficiency water reducer, the fluidity of the concrete can be improved and the amount of water can be reduced. At the same time, the use of a water retainer, such as a polymer additive, can improve the water retention of the concrete and promote the activity of microorganisms. The polymer emulsion is an aqueous polymer emulsion, which is a polyvinyl alcohol (PVA) emulsion, which is used to improve the toughness and adhesion of the concrete. The amount of calcium lactate added is 1% of the weight of the cement, and the addition ratio of the polymer emulsion is 5% of the weight of the cement.

[0255] Preferably, in the step S33, during the mixing of recycled coarse aggregate, sand and cement, a mixture of calcium precipitating bacteria, silicate bacteria and urea is added, wherein the amount of urea added is 0.5% of the amount of cement, the temperature during the mixing process is 28 degrees Celsius, the mixing time is 3 minutes, and a low shear mixing method is adopted to avoid microbial damage caused by excessive stirring; the amount of calcium precipitating bacteria and silicate bacteria added is 5% of the amount of cement.

[0256] In this embodiment, during the concrete mixing process, a mixed bacteria formed by calcium-precipitating bacteria and silicate bacteria is added with urea as a nutrient matrix, and urea is used as a nitrogen source to promote the growth of microorganisms. The calcium-precipitating bacteria can promote calcium precipitation when cracks are generated, and the silicate bacteria can promote silicate precipitation when cracks are generated, thereby enhancing the strength of the concrete and thus improving the crack repair effect.

[0257] By wrapping hydrogel on the surface of bacteria-containing expanded perlite, hydrogel is a hydrophilic gel with a polymer chain network, which has high water absorption and can retain a large amount of water or aqueous solution. Hydrogel can not only protect microorganisms but also be used as a water storage agent, increase the crack filling amount and reduce water permeability, enhance the living environment of microorganisms, provide water and nutrition for microorganisms, maintain the activity of microorganisms, and thus improve the crack repair effect.

[0258] This design application is applied to roof waterproofing in building construction. Expanded perlite is used as a microbial carrier. Bacillus and aerobic mixed bacteria are mixed into concrete to form microbial concrete. The microbial concrete is then poured onto the roof waterproofing membrane to form a protective layer to complete the construction of roof waterproofing. The purpose is to quickly complete self-repair when cracks appear in the concrete, and to improve the aesthetics and strength of the repaired area.

[0259] Example 10

[0260] As attached Figure 1 To Attachment Figure 6 The present embodiment provides a method for constructing a roof waterproof protective layer based on microbial concrete, and the specific steps are as follows:

[0261] S1. Microbial culture: a liquid culture medium is used to culture mixed Bacillus, and a culture fluid is used to culture aerobic mixed bacteria; the mixed Bacillus includes Bacillus sphaericus, Bacillus pasteurianus and Bacillus cohnii.

[0262] S2. Protective carrier encapsulation: Expanded perlite particles P1 are used as microbial carriers, and the obtained mixed Bacillus and aerobic mixed bacteria are adsorbed on the surface and internal gaps of the expanded perlite particles P1 to obtain bacteria-containing expanded perlite particles P2;

[0263] S3, concrete preparation: mixing recycled coarse aggregate, sand and cement to obtain microbial concrete H1;

[0264] S4, concrete pouring: pouring the obtained microbial concrete onto the roof waterproof layer to form a roof waterproof protective layer;

[0265] S5. Concrete maintenance: Maintain the formed roof waterproof protective layer, maintain a moist environment, promote the activity of microorganisms and the solidification of concrete.

[0266] Preferably, the aerobic mixed bacteria in step S1 include Bacillus Pasteurii and alkaliphilic bacteria, wherein the Bacillus Pasteurii accounts for 50% and the alkaliphilic bacteria accounts for 40% in terms of volume percentage.

[0267] Preferably, the specific operation steps of step S2 are:

[0268] S21: Adsorbing the bacterial solution of mixed Bacillus and aerobic mixed bacteria onto the surface and internal voids of the expanded pearlite particles P1 at a pressure of -0.06 MPa by a vacuum impregnation method;

[0269] S22: drying the expanded perlite particles P1 after adsorption at 42 degrees Celsius to a constant weight;

[0270] S23: spraying yeast extract solution on the surface of the expanded perlite particles P1;

[0271] S24: Dry the expanded perlite particles P1 again at 42 degrees Celsius to constant weight, obtaining a particle size of 5 mm and a bulk density of 80 kg / m 3 The bacteria-containing expanded perlite particles P2.

[0272] Preferably, the specific operation steps of step S3 are:

[0273] S31: liquid L obtained by mixing metakaolin, sodium silicate solution and water;

[0274] S32: coating the outer surface of the bacteria-containing expanded perlite particles P2 with liquid L to obtain bacteria-containing expanded perlite particles P21;

[0275] S33: mixing recycled coarse aggregate, sand and cement;

[0276] S34: Add the bacteria-containing expanded perlite particles P21 in the final stage of mixing, and obtain the microbial concrete H1 after mixing.

[0277] Preferably, in the step S2, the bacteria-containing expanded perlite particles P2 and the hydrogel are uniformly mixed in a ratio of 3:1, so that the hydrogel uniformly wraps the outside of the bacteria-containing expanded perlite particles P2.

[0278] Preferably, the steps for preparing the recycled coarse aggregate in step S33 are as follows:

[0279] S331: mixing the coarse aggregate raw material with the aerobic mixed bacteria to make the microorganisms evenly distributed on the coarse aggregate raw material;

[0280] S332: Soaking the mixed coarse aggregate raw materials in a nutrient solution for mineralization, wherein the mineralization temperature is controlled at 30 degrees Celsius; the nutrient solution is an aqueous solution containing urea, phosphate, potassium chloride, iron and zinc.

[0281] S333: After 5 days of mineralization, recycled coarse aggregate is obtained.

[0282] Preferably, in the step S33, calcium lactate and polymer emulsion are added during the mixing of recycled coarse aggregate, sand and cement, and then a water reducer and a water retainer are added. The amount of the water reducer added is 2% of the weight of the cement, and the amount of the water retainer added is 3% of the weight of the cement. By using a high-efficiency water reducer, the fluidity of the concrete can be improved and the amount of water can be reduced. At the same time, the use of a water retainer, such as a polymer additive, can improve the water retention of the concrete and promote the activity of microorganisms. The polymer emulsion is an aqueous polymer emulsion, which is a polyvinyl alcohol (PVA) emulsion, which is used to improve the toughness and adhesion of the concrete. The amount of calcium lactate added is 3% of the weight of the cement, and the addition ratio of the polymer emulsion is 15% of the weight of the cement.

[0283] Preferably, in the step S33, during the mixing of recycled coarse aggregate, sand and cement, a mixture of calcium precipitating bacteria, silicate bacteria and urea is added, wherein the amount of urea added is 2% of the amount of cement, the temperature during the mixing process is 30 degrees Celsius, the mixing time is 5 minutes, and a low shear mixing method is adopted to avoid microbial damage caused by excessive stirring; the amount of calcium precipitating bacteria and silicate bacteria added is 1% of the amount of cement.

[0284] In this embodiment, during the concrete mixing process, a mixed bacteria formed by calcium-precipitating bacteria and silicate bacteria is added with urea as a nutrient matrix, and urea is used as a nitrogen source to promote the growth of microorganisms. The calcium-precipitating bacteria can promote calcium precipitation when cracks are generated, and the silicate bacteria can promote silicate precipitation when cracks are generated, thereby enhancing the strength of the concrete and thus improving the crack repair effect.

[0285] By wrapping hydrogel on the surface of bacteria-containing expanded perlite, hydrogel is a hydrophilic gel with a polymer chain network, which has high water absorption and can retain a large amount of water or aqueous solution. Hydrogel can not only protect microorganisms but also be used as a water storage agent, increase the crack filling amount and reduce water permeability, enhance the living environment of microorganisms, provide water and nutrition for microorganisms, maintain the activity of microorganisms, and thus improve the crack repair effect.

[0286] This design application is applied to roof waterproofing in building construction. Expanded perlite is used as a microbial carrier. Bacillus and aerobic mixed bacteria are mixed into concrete to form microbial concrete. The microbial concrete is then poured onto the roof waterproofing membrane to form a protective layer to complete the construction of roof waterproofing. The purpose is to quickly complete self-repair when cracks appear in the concrete, and to improve the aesthetics and strength of the repaired area.

[0287] Embodiment 11

[0288] As attached Figure 1 To Attachment Figure 6 The present embodiment provides a method for constructing a roof waterproof protective layer based on microbial concrete, and the specific steps are as follows:

[0289] S1. Microbial culture: a liquid culture medium is used to culture mixed Bacillus, and a culture fluid is used to culture aerobic mixed bacteria; the mixed Bacillus includes Bacillus sphaericus, Bacillus pasteurianus and Bacillus cohnii.

[0290] S2. Protective carrier encapsulation: Expanded perlite particles P1 are used as microbial carriers, and the obtained mixed Bacillus and aerobic mixed bacteria are adsorbed on the surface and internal gaps of the expanded perlite particles P1 to obtain bacteria-containing expanded perlite particles P2;

[0291] S3, concrete preparation: mixing recycled coarse aggregate, sand and cement to obtain microbial concrete H1;

[0292] S4, concrete pouring: pouring the obtained microbial concrete onto the roof waterproof layer to form a roof waterproof protective layer;

[0293] S5. Concrete maintenance: Maintain the formed roof waterproof protective layer, maintain a moist environment, promote the activity of microorganisms and the solidification of concrete.

[0294] Preferably, the aerobic mixed bacteria in step S1 include Bacteroides, Bacillus subtilis and Ureacoccus, wherein, in terms of volume percentage, Ureacoccus accounts for 15%, the Bacteroides accounts for 16%, and the Bacillus subtilis accounts for 32%.

[0295] Preferably, the aerobic mixed bacteria in step S1 include Bacillus Pasteurii and alkaliphilic bacteria, wherein the Bacillus Pasteurii accounts for 30% and the alkaliphilic bacteria accounts for 20% in terms of volume percentage.

[0296] Preferably, the specific operation steps of step S2 are:

[0297] S21: Adsorbing the bacterial solution of mixed Bacillus and aerobic mixed bacteria onto the surface and internal voids of the expanded pearlite particles P1 at a pressure of -0.06 MPa by a vacuum impregnation method;

[0298] S22: drying the expanded perlite particles P1 after adsorption at 38 degrees Celsius to a constant weight;

[0299] S23: spraying yeast extract solution on the surface of the expanded perlite particles P1;

[0300] S24: Dry the expanded perlite particles P1 again at 38 degrees Celsius to constant weight, obtaining a particle size of 2 mm and a bulk density of 76 kg / m 3 The bacteria-containing expanded perlite particles P2.

[0301] Preferably, the specific operation steps of step S3 are:

[0302] S31: liquid L obtained by mixing metakaolin, sodium silicate solution and water;

[0303] S32: coating the outer surface of the bacteria-containing expanded perlite particles P2 with liquid L to obtain bacteria-containing expanded perlite particles P21;

[0304] S33: mixing recycled coarse aggregate, sand and cement;

[0305] S34: Add the bacteria-containing expanded perlite particles P21 in the final stage of mixing, and obtain the microbial concrete H1 after mixing.

[0306] Preferably, in the step S2, the bacteria-containing expanded perlite particles P2 and the hydrogel are uniformly mixed in a ratio of 3:1, so that the hydrogel uniformly wraps the outside of the bacteria-containing expanded perlite particles P2.

[0307] Preferably, the steps for preparing the recycled coarse aggregate in step S33 are as follows:

[0308] S331: mixing the coarse aggregate raw material with the aerobic mixed bacteria to make the microorganisms evenly distributed on the coarse aggregate raw material;

[0309] S332: Soaking the mixed coarse aggregate raw materials in a nutrient solution for mineralization, wherein the mineralization temperature is controlled at 25 degrees Celsius; the nutrient solution is an aqueous solution containing urea, phosphate, potassium chloride, iron and zinc.

[0310] S333: After 3 days of mineralization, recycled coarse aggregate is obtained.

[0311] Preferably, in the step S33, calcium lactate and polymer emulsion are added during the mixing of recycled coarse aggregate, sand and cement, and then a water reducer and a water retainer are added. The amount of the water reducer added is 0.5% of the weight of the cement, and the amount of the water retainer added is 1% of the weight of the cement. By using a high-efficiency water reducer, the fluidity of the concrete can be improved and the amount of water can be reduced. At the same time, the use of a water retainer, such as a polymer additive, can improve the water retention of the concrete and promote the activity of microorganisms. The polymer emulsion is an aqueous polymer emulsion, which is a polyvinyl alcohol (PVA) emulsion, which is used to improve the toughness and adhesion of the concrete. The amount of calcium lactate added is 1% of the weight of the cement, and the addition ratio of the polymer emulsion is 5% of the weight of the cement.

[0312] Preferably, in the step S33, during the mixing of recycled coarse aggregate, sand and cement, a mixture of calcium precipitating bacteria, silicate bacteria and urea is added, wherein the amount of urea added is 0.5% of the amount of cement, the temperature during the mixing process is 26 degrees Celsius, the mixing time is 3 minutes, and a low shear mixing method is adopted to avoid microbial damage caused by excessive stirring; the amount of calcium precipitating bacteria and silicate bacteria added is 1% of the amount of cement.

[0313] In this embodiment, during the concrete mixing process, a mixed bacteria formed by calcium-precipitating bacteria and silicate bacteria is added with urea as a nutrient matrix, and urea is used as a nitrogen source to promote the growth of microorganisms. The calcium-precipitating bacteria can promote calcium precipitation when cracks are generated, and the silicate bacteria can promote silicate precipitation when cracks are generated, thereby enhancing the strength of the concrete and thus improving the crack repair effect.

[0314] By wrapping hydrogel on the surface of bacteria-containing expanded perlite, hydrogel is a hydrophilic gel with a polymer chain network, which has high water absorption and can retain a large amount of water or aqueous solution. Hydrogel can not only protect microorganisms but also be used as a water storage agent, increase the crack filling amount and reduce water permeability, enhance the living environment of microorganisms, provide water and nutrition for microorganisms, maintain the activity of microorganisms, and thus improve the crack repair effect.

[0315] This design application is applied to roof waterproofing in building construction. Expanded perlite is used as a microbial carrier. Bacillus and aerobic mixed bacteria are mixed into concrete to form microbial concrete. The microbial concrete is then poured onto the roof waterproofing membrane to form a protective layer to complete the construction of roof waterproofing. The purpose is to quickly complete self-repair when cracks appear in the concrete, and to improve the aesthetics and strength of the repaired area.

[0316] Example 12

[0317] As attached Figure 1 To Attachment Figure 6 The present embodiment provides a method for constructing a roof waterproof protective layer based on microbial concrete, and the specific steps are as follows:

[0318] S1. Microbial culture: a liquid culture medium is used to culture mixed Bacillus, and a culture fluid is used to culture aerobic mixed bacteria; the mixed Bacillus includes Bacillus sphaericus, Bacillus pasteurianus and Bacillus cohnii.

[0319] S2. Protective carrier encapsulation: Expanded perlite particles P1 are used as microbial carriers, and the obtained mixed Bacillus and aerobic mixed bacteria are adsorbed on the surface and internal gaps of the expanded perlite particles P1 to obtain bacteria-containing expanded perlite particles P2;

[0320] S3, concrete preparation: mixing recycled coarse aggregate, sand and cement to obtain microbial concrete H1;

[0321] S4, concrete pouring: pouring the obtained microbial concrete onto the roof waterproof layer to form a roof waterproof protective layer;

[0322] S5. Concrete maintenance: Maintain the formed roof waterproof protective layer, maintain a moist environment, promote the activity of microorganisms and the solidification of concrete.

[0323] Preferably, the aerobic mixed bacteria in step S1 include Bacteroides, Bacillus subtilis and Ureacoccus, wherein, in terms of volume percentage, Ureacoccus accounts for 18%, Bacteroides accounts for 20%, and Bacillus subtilis accounts for 35%.

[0324] Preferably, the aerobic mixed bacteria in step S1 include Bacillus Pasteurii and alkaliphilic bacteria, wherein the Bacillus Pasteurii accounts for 50% and the alkaliphilic bacteria accounts for 40% in terms of volume percentage.

[0325] Preferably, the specific operation steps of step S2 are:

[0326] S21: Adsorbing the bacterial solution of mixed Bacillus and aerobic mixed bacteria onto the surface and internal voids of the expanded pearlite particles P1 at a pressure of -0.06 MPa by a vacuum impregnation method;

[0327] S22: drying the expanded perlite particles P1 after adsorption at 42 degrees Celsius to a constant weight;

[0328] S23: spraying yeast extract solution on the surface of the expanded perlite particles P1;

[0329] S24: Dry the expanded perlite particles P1 again at 42 degrees Celsius to constant weight, obtaining a particle size of 5 mm and a bulk density of 80 kg / m 3 The bacteria-containing expanded perlite particles P2.

[0330] Preferably, the specific operation steps of step S3 are:

[0331] S31: liquid L obtained by mixing metakaolin, sodium silicate solution and water;

[0332] S32: coating the outer surface of the bacteria-containing expanded perlite particles P2 with liquid L to obtain bacteria-containing expanded perlite particles P21;

[0333] S33: mixing recycled coarse aggregate, sand and cement;

[0334] S34: Add the bacteria-containing expanded perlite particles P21 in the final stage of mixing, and obtain the microbial concrete H1 after mixing.

[0335] Preferably, in the step S2, the bacteria-containing expanded perlite particles P2 and the hydrogel are uniformly mixed in a ratio of 3:1, so that the hydrogel uniformly wraps the outside of the bacteria-containing expanded perlite particles P2.

[0336] Preferably, the steps for preparing the recycled coarse aggregate in step S33 are as follows:

[0337] S331: mixing the coarse aggregate raw material with the aerobic mixed bacteria to make the microorganisms evenly distributed on the coarse aggregate raw material;

[0338] S332: Soaking the mixed coarse aggregate raw materials in a nutrient solution for mineralization, wherein the mineralization temperature is controlled at 30 degrees Celsius; the nutrient solution is an aqueous solution containing urea, phosphate, potassium chloride, iron and zinc.

[0339] S333: After 5 days of mineralization, recycled coarse aggregate is obtained.

[0340] Preferably, in the step S33, calcium lactate and polymer emulsion are added during the mixing of recycled coarse aggregate, sand and cement, and then a water reducer and a water retainer are added. The amount of the water reducer added is 2% of the weight of the cement, and the amount of the water retainer added is 3% of the weight of the cement. By using a high-efficiency water reducer, the fluidity of the concrete can be improved and the amount of water can be reduced. At the same time, the use of a water retainer, such as a polymer additive, can improve the water retention of the concrete and promote the activity of microorganisms. The polymer emulsion is an aqueous polymer emulsion, which is a polyvinyl alcohol (PVA) emulsion, which is used to improve the toughness and adhesion of the concrete. The amount of calcium lactate added is 3% of the weight of the cement, and the addition ratio of the polymer emulsion is 15% of the weight of the cement.

[0341] Preferably, in the step S33, during the mixing of recycled coarse aggregate, sand and cement, a mixture of calcium precipitating bacteria, silicate bacteria and urea is added, wherein the amount of urea added is 2% of the amount of cement, the temperature during the mixing process is 30 degrees Celsius, the mixing time is 5 minutes, and a low shear mixing method is adopted to avoid microbial damage caused by excessive stirring; the amount of calcium precipitating bacteria and silicate bacteria added is 5% of the amount of cement.

[0342] In this embodiment, during the concrete mixing process, a mixed bacteria formed by calcium-precipitating bacteria and silicate bacteria is added with urea as a nutrient matrix, and urea is used as a nitrogen source to promote the growth of microorganisms. The calcium-precipitating bacteria can promote calcium precipitation when cracks are generated, and the silicate bacteria can promote silicate precipitation when cracks are generated, thereby enhancing the strength of the concrete and thus improving the crack repair effect.

[0343] By wrapping hydrogel on the surface of bacteria-containing expanded perlite, hydrogel is a hydrophilic gel with a polymer chain network, which has high water absorption and can retain a large amount of water or aqueous solution. Hydrogel can not only protect microorganisms but also be used as a water storage agent, increase the crack filling amount and reduce water permeability, enhance the living environment of microorganisms, provide water and nutrition for microorganisms, maintain the activity of microorganisms, and thus improve the crack repair effect.

[0344] This design application is applied to roof waterproofing in building construction. Expanded perlite is used as a microbial carrier. Bacillus and aerobic mixed bacteria are mixed into concrete to form microbial concrete. The microbial concrete is then poured onto the roof waterproofing membrane to form a protective layer to complete the construction of roof waterproofing. The purpose is to quickly complete self-repair when cracks appear in the concrete, and to improve the aesthetics and strength of the repaired area.

[0345] Importantly, it should be noted that the construction and arrangement of the present application shown in a plurality of different exemplary embodiments are only exemplary. Although only a few embodiments are described in detail in this disclosure, it should be readily understood by those who refer to this disclosure that many modifications are possible (e.g., the size, scale, structure, shape and proportion of various elements, and parameter values ​​(e.g., temperature, pressure, etc.), installation arrangement, use of materials, color, directional changes, etc.) without substantially departing from the novel teachings and advantages of the subject matter described in the application. For example, the element shown as integrally formed can be composed of multiple parts or elements, the position of the element can be inverted or otherwise changed, and the nature or number or position of the discrete element can be changed or changed. Therefore, all such modifications are intended to be included in the scope of the present invention. The order or sequence of any process or method steps can be changed or reordered according to alternative embodiments. In the claims, any "device plus function" clause is intended to cover the structure of performing the function described herein, and is not only structurally equivalent but also equivalent structure. Without departing from the scope of the present invention, other replacements, modifications, changes and omissions can be made in the design, operating conditions and arrangement of the exemplary embodiments. Therefore, the invention is not limited to a specific embodiment, but extends to numerous modifications still falling within the scope of the appended claims.

[0346] Additionally, in order to provide a concise description of exemplary embodiments, all features of an actual embodiment (ie, those features that are not relevant to the best mode presently contemplated for carrying out the invention or those that are not relevant to implementing the invention) may not be described.

[0347] It will be appreciated that in the development of any actual implementation, as in any engineering or design project, numerous implementation-specific decisions may be made. Such a development effort may be complex and time-consuming, but will be a routine task of design, fabrication, and production for those of ordinary skill having the benefit of this disclosure without undue experimentation.

[0348] The present invention and its embodiments are described schematically above, and the description is not restrictive. The drawings show only one embodiment of the present invention, and the actual structure is not limited thereto. Therefore, if a person skilled in the art is inspired by it and designs a structural method and an embodiment similar to the technical solution without creativity without departing from the purpose of the invention, they shall all fall within the protection scope of the present invention.

Claims

1. A method for constructing a roof waterproof protective layer based on microbial concrete, characterized in that: The specific steps are as follows: S1. Microbial culture: using liquid culture medium to culture mixed Bacillus, and using culture fluid to culture aerobic mixed bacteria; the mixed Bacillus is one or more of Bacillus sphaericus, Bacillus pasteurianus and Bacillus cohnii; S2. Protective carrier encapsulation: Expanded perlite particles P1 are used as microbial carriers, and the obtained mixed Bacillus and aerobic mixed bacteria are adsorbed on the surface and internal gaps of the expanded perlite particles P1 to obtain bacteria-containing expanded perlite particles P2; S3, concrete preparation: mixing recycled coarse aggregate, sand and cement to obtain microbial concrete H1; S4, concrete pouring: pouring the obtained microbial concrete onto the roof waterproof layer to form a roof waterproof protective layer; S5. Concrete maintenance: Maintain the formed roof waterproof protective layer, maintain a moist environment, promote the activity of microorganisms and the solidification of concrete.

2. A method for constructing a roof waterproof protective layer based on microbial concrete according to claim 1, characterized in that: The aerobic mixed bacteria in step S1 include Bacteroides, Bacillus subtilis and Ureacoccus, wherein the Ureacoccus accounts for 15% to 18%, the Bacteroides accounts for 16% to 20%, and the Bacillus subtilis accounts for 32% to 35% in terms of volume percentage.

3. The method for constructing a roof waterproof protective layer based on microbial concrete according to claim 1, characterized in that: The aerobic mixed bacteria in step S1 include Bacillus Pasteurii and alkaliphilic bacteria, wherein the Bacillus Pasteurii accounts for 30% to 50% and the alkaliphilic bacteria accounts for 20% to 40% in terms of volume percentage.

4. A method for constructing a roof waterproof protective layer based on microbial concrete according to any one of claims 2 or 3, characterized in that: The specific operation steps of the S2 step are: S21: Adsorbing the bacterial solution of mixed Bacillus and aerobic mixed bacteria onto the surface and internal voids of the expanded pearlite particles P1 at a pressure of -0.06 MPa by a vacuum impregnation method; S22: drying the expanded perlite particles P1 after adsorption to a constant weight at 38-42 degrees Celsius; S23: spraying yeast extract solution on the surface of the expanded perlite particles P1; S24: Dry the expanded perlite particles P1 again at 38-42 degrees Celsius to constant weight, obtaining a particle size of 2-5 mm and a bulk density of 76-80 kg / m 3 The bacteria-containing expanded perlite particles P2.

5. A method for constructing a roof waterproof protective layer based on microbial concrete according to claim 4, characterized in that: The specific operation steps of the S3 step are: S31: liquid L obtained by mixing metakaolin, sodium silicate solution and water; S32: coating the outer surface of the bacteria-containing expanded perlite particles P2 with liquid L to obtain bacteria-containing expanded perlite particles P21; S33: mixing recycled coarse aggregate, sand and cement; S34: Add the bacteria-containing expanded perlite particles P21 in the final stage of mixing, and obtain the microbial concrete H1 after mixing.

6. A method for constructing a roof waterproof protective layer based on microbial concrete according to claim 5, characterized in that: In the step S2, the bacteria-containing expanded perlite particles P2 and the hydrogel are uniformly mixed in a ratio of 3:1, so that the hydrogel uniformly wraps the outside of the bacteria-containing expanded perlite particles P2.

7. A method for constructing a roof waterproof protective layer based on microbial concrete according to claim 6, characterized in that: The steps for preparing the recycled coarse aggregate in step S33 are as follows: S331: mixing the coarse aggregate raw material with the aerobic mixed bacteria to make the microorganisms evenly distributed on the coarse aggregate raw material; S332: Soaking the mixed coarse aggregate raw materials in a nutrient solution for mineralization, wherein the mineralization temperature is controlled to be 25 degrees Celsius to 30 degrees Celsius; S333: After 3 to 5 days of mineralization, recycled coarse aggregate is obtained.

8. The method for constructing a roof waterproof protective layer based on microbial concrete according to claim 7, characterized in that: In the step S33, during the mixing of recycled coarse aggregate, sand and cement, calcium lactate and polymer emulsion are added, and then a water reducing agent and a water retaining agent are added. The amount of the water reducing agent added is 0.5% to 2% of the weight of the cement, and the amount of the water retaining agent added is 1% to 3% of the weight of the cement.

9. A method for constructing a roof waterproof protective layer based on microbial concrete according to claim 8, characterized in that: In the step S33, during the mixing of recycled coarse aggregate, sand and cement, a mixture of calcium precipitating bacteria, silicate bacteria and urea is added, wherein the amount of urea added is 0.5% to 2% of the amount of cement used, the temperature during the mixing process does not exceed 30 degrees Celsius, the mixing time is 3 to 5 minutes, and a low shear mixing method is adopted.

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