High-temperature frozen soil foundation reinforcement method based on ice nucleation active bacteria

Abstract

The present invention relates to a high-temperature frozen soil foundation reinforcement method based on ice nucleation-active bacteria. Existing frozen soil foundation reinforcement measures have problems such as insufficient performance and pollution of frozen soil resources. The present invention prepares a culture medium; utilizes the culture medium to culture ice nucleation-active bacteria; obtains an ice nucleation-active bacteria solution; injects the ice nucleation-active bacteria solution into the high-temperature frozen soil in the high-temperature frozen soil foundation area that needs to be reinforced; the ice nucleation-active bacteria grow and multiply in the high-temperature frozen soil, and when their number reaches a certain concentration in the reinforcement area, the ice nucleation-active protein anchored in its cell outer membrane can increase the freezing point of unfrozen water in the high-temperature frozen soil, and the ice nucleation-active bacteria will promote the formation of ice crystals at the corresponding high-temperature frozen soil temperature, thereby reinforcing the high-temperature frozen soil foundation. The present invention utilizes ice nucleation-active bacteria to reinforce the high-temperature frozen soil foundation, which is green, environmentally friendly, sustainable, not restricted by seasonal changes, has little disturbance to the frozen soil, and can prevent the invasion of foreign organisms from causing local biological pollution.

Description

Technical Field

[0001] The present invention relates to the technical field of frozen soil foundation reinforcement, and in particular to a high-temperature frozen soil foundation reinforcement method based on ice nucleation active bacteria. Background Art

[0002] Permafrost, with a temperature above -1°C, remains extremely compressible even in its frozen state. With global warming and increasing engineering activity, the area of ​​permafrost is expanding globally, particularly in my country's Qinghai-Tibet Plateau, where permafrost temperatures above -1.5°C to -0.5°C will dominate in the future. According to a survey, over 30% of the projects along the 1,400-kilometer Qinghai-Tibet Engineering Corridor pass through permafrost zones, with ongoing development. This situation has direct consequences: frequent permafrost thaw-settlement disasters, a reduction in the bearing capacity of permafrost foundations, and the resulting instability, collapse, and landslide damage to structures built on permafrost. It is estimated that the total deformation of the Qinghai-Tibet Plateau could reach 30 centimeters over the next 50 years.

[0003] Existing active cooling measures, such as heat rods, ventilation duct roadbeds, sunshade roadbeds, block stone roadbeds, and dry bridges, are relatively costly, have low thermal efficiency, poor seasonal adaptability, and poor controllability. Furthermore, with global warming, these measures are no longer sufficient to address the hazards of environmental change. For example, thaw settlement damage on the Qinghai-Tibet Highway and railway lines accounts for 50% and 85% of surveyed bridge damage, respectively. Furthermore, some chemical reinforcement methods for permafrost roadbeds primarily involve adding inorganic solidifying agents such as cement to the permafrost to enhance its strength. However, these methods are merely borrowed from methods used to treat soft soil foundations and fail to fundamentally address the thaw settlement of permafrost under rising temperatures. Furthermore, they can cause stratification between reinforced and unreinforced areas. Furthermore, solidifying agents such as cement and fly ash used to reinforce permafrost not only pollute permafrost resources and the local environment but also increase carbon emissions in permafrost areas. Therefore, there is an urgent need to explore new, sustainable, and environmentally friendly permafrost reinforcement measures to ensure the long-term bearing capacity and stability of permafrost foundations, thereby enhancing the safe operation of transportation projects built on permafrost in cold regions and extending the service life of transportation facilities. Summary of the Invention

[0004] The purpose of the present invention is to provide a high-temperature frozen soil foundation reinforcement method based on ice nucleation active bacteria to solve the problems of insufficient performance and pollution of frozen soil resources in existing frozen soil foundation reinforcement measures.

[0005] In order to achieve the above object, the technical solution adopted by the present invention is:

[0006] A high-temperature frozen soil foundation reinforcement method based on ice nucleation active bacteria, the method comprising:

[0007] Prepare culture medium;

[0008] Cultivating ice nucleation-active bacteria using culture medium;

[0009] Obtain ice nucleation active bacterial solution;

[0010] Injecting ice nucleation active bacterial solution into the high temperature frozen soil in the high temperature frozen soil foundation area that needs to be reinforced;

[0011] Ice nucleation-active bacteria grow and multiply in high-temperature frozen soil;

[0012] The ice nucleation-active protein anchored in the outer membrane of ice-nucleation-active bacteria provides a template for the growth of ice in high-temperature permafrost. By raising the freezing point of unfrozen water in high-temperature permafrost, the unfrozen water in high-temperature permafrost freezes, thereby strengthening the high-temperature permafrost foundation.

[0013] Furthermore, the formula of the culture medium is:

[0014] Beef extract 3g, peptone 10g, sodium chloride 5g, distilled water 1000mL.

[0015] Furthermore, the pH value of the culture medium is 7.0.

[0016] Furthermore, the ice nucleation-active bacteria are selected from Pseudomonas syringae, Pseudomonas antarctica, and Pseudomonas polaris.

[0017] Furthermore, glycerol is added to the ice nucleation active bacteria solution in an amount of 0.5% to 1.2% of the volume of the ice nucleation active bacteria solution.

[0018] Furthermore, the method further comprises:

[0019] Deploy moisture sensors in high-temperature frozen soil injected with a solution of ice-nucleating bacteria;

[0020] Use moisture sensors to monitor the unfrozen water content of high-temperature frozen soil in real time;

[0021] If the unfrozen water content of the high-temperature frozen soil is higher than the local moisture content allowable range, ice nucleation active bacterial solution will be injected.

[0022] Furthermore, the process of obtaining the allowable range of local moisture content is as follows:

[0023] Drill holes on-site in the high-temperature frozen soil foundation area that needs to be reinforced and collect frozen soil samples to measure the natural moisture content of the frozen soil samples;

[0024] The reshaped specimens were made in the laboratory and the optimal moisture content of the reshaped specimens was obtained through compaction tests;

[0025] Through shear test, the most unfavorable moisture content of the reshaped specimen is obtained;

[0026] The local allowable moisture content range is obtained through the natural moisture content, optimal moisture content and most unfavorable moisture content.

[0027] Compared with the prior art, the present invention has the following beneficial effects:

[0028] This method utilizes ice nucleating active bacteria (INAB) to reinforce high-temperature frozen ground. It is a green, environmentally friendly, and sustainable method for reinforcing frozen ground. The INAB, derived from native bacteria already present in frozen soil, is more adaptable to the harsh environments of cold regions, unaffected by seasonal fluctuations, and exhibits excellent performance. Adding the bacterial solution also promotes the growth of native INAB, minimizing permafrost disturbance and preventing contamination by foreign organisms.

[0029] In addition, the present invention uses an ice nucleation-active bacterial solution, which can take advantage of the frozen soil for growth and reproduction after being artificially injected into the frozen soil. This is because the cold environment is suitable for the survival of ice nucleation-active bacteria and different types of native ice nucleation-active bacteria are distributed in the frozen soil. Artificial injection and native ice nucleation bacteria can have a superimposed effect, so that the number of ice nucleation-active bacteria reaches a certain concentration in the area that needs reinforcement in a short period of time, and then takes effect. The reinforcement cost is significantly lower than traditional measures. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, without paying any creative work, they can also obtain drawings of other embodiments based on these drawings.

[0031] Figure 1 It is the relationship curve between the shear strength of frozen soil and the change of normal pressure before and after the reinforcement of high-temperature frozen soil foundation. DETAILED DESCRIPTION

[0032] To facilitate understanding of the present invention, the present invention will be described more fully below with reference to the accompanying drawings. The detailed description provides preferred embodiments of the present invention. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a more thorough and comprehensive understanding of the disclosure of the present invention.

[0033] In the description of the present invention, it is to be understood that all technologies and scientific terms used have the same meaning as those of ordinary skill in the art to which the present invention belongs. When there is a contradiction, the definition in this specification shall prevail. If not otherwise specified, the technical means used in the embodiment are conventional means well known to those skilled in the art, the reagent used in the embodiment is a commercially available product, and the device used in the embodiment is an existing device, and the limitation of means, reagent or device can not be interpreted as limitation of the present invention, and the means, reagent or device for solving the same technical problems of the same type are within protection scope of the present invention.

[0034] In the description of the present invention, it should be understood that when an amount, concentration, or other value or parameter is expressed as a range, a preferred range, or a range limited by a series of upper preferred values ​​and lower preferred values, this should be understood to specifically disclose all ranges formed by any pairing of any range upper limit or preferred value with any range lower limit or preferred value, regardless of whether the range is disclosed separately. When a numerical range is described in this article, unless otherwise stated, the range is intended to include its end values ​​and all integers and fractions within the range.

[0035] In the description of the present invention, it should be understood that multiple steps are involved in the description of the method, which should not be understood as a limitation on the order of the method steps. Technical solutions obtained by simply changing the order of the steps when solving the same technical problem are also within the scope of protection of the present invention.

[0036] Under standard atmospheric pressure, the freezing temperature of free water is 0°C, while the freezing temperature of unfrozen water in soil is below 0°C due to the interaction between soil particles. This is especially true for fine-grained soils, where the high fine particle content leads to strong electromolecular attraction between particles and a thick bound water film, resulting in a lower freezing temperature. For example, at a temperature of -10°C, clay still retains a large amount of unfrozen water. High-temperature frozen soils, situated in the ice-water phase transition zone, have a high unfrozen water content and a low ice content. This leads to significant compression and deformation of the frozen soil, causing thaw settlement and a reduction in bearing capacity in the high-temperature frozen soil foundation. Consequently, structures built on top of the frozen soil can become unstable, collapse, or even slide.

[0037] Current frozen soil reinforcement measures generally consider using various means to dissipate heat from the frozen soil to maintain ice consolidation. However, the present invention's method for maintaining the ice content of frozen soil does not rely on this method. Instead, the reinforcement strategy of the present invention is to increase the freezing point of unfrozen water within the frozen soil, thereby promoting the formation of ice crystals. This goal is achieved through biological means. Ice-nucleating active bacteria (INAB) are a type of bacteria that can specifically express ice-nucleating active proteins. Highly active ice-nucleating active proteins are type I ice-nucleating active proteins, and ice-nucleating active bacteria that express type I ice-nucleating active proteins are considered type I ice-nucleating active bacteria. Ice-nucleating active bacteria are the strongest heterogeneous ice nuclei. Their biological ice-nucleating activity is exerted because the ice-nucleating active proteins can arrange water molecules into an ice-like lattice, providing a template for ice growth, thereby raising the freezing point of water and promoting the water-ice phase transition in a short period of time. Ice-nucleating active bacteria are ice nuclei. Ice nuclei are ice embryos, the prototypes of ice crystals. Ice nuclei can develop into large ice crystals, and water can continue to grow and expand around the ice nuclei or large ice crystals. For example, pure water can be kept in a supercooled state at -40°C, but after adding Pseudomonas syringae, it can form ice at -2°C. In addition, as long as the ice nucleation protein of ice nucleation-active bacteria exists, even dead ice nucleation-active bacteria can still function as biological ice nuclei. It can be seen that ice nucleation-active bacteria increase the freezing point of unfrozen water in high-temperature permafrost, causing the unfrozen water in the permafrost to freeze at a relatively high temperature. Not only will the original ice crystals in the high-temperature permafrost not melt, but they can also serve as ice nuclei, providing more ice embryos for organisms to promote the growth of ice crystals. The method of the present invention can maintain the ice content of permafrost by biological means without dissipating the heat in the permafrost to ensure its carrying capacity.

[0038] The present invention provides a high-temperature frozen soil foundation reinforcement method based on ice nucleation-active bacteria, which uses ice nucleation-active bacteria to increase the freezing point of unfrozen water in the frozen soil, thereby freezing the water in the frozen soil at a relatively high temperature, maintaining its bearing capacity and achieving a reinforcement effect.

[0039] The ice-nucleating bacteria described in the present invention are Type I ice-nucleating bacteria that specifically express Type I ice-nucleating proteins, selected from one or more of Pseudomonas syringae, Pseudomonas antarctica, and Pseudomonas borealis. Although these Type I ice-nucleating bacteria are artificially cultured and injected, they are all native ice-nucleating bacteria that are also present in the permafrost and are widely distributed within the permafrost. In addition, other types of native ice-nucleating bacteria are also distributed within the permafrost, as are some ice-nucleating fungi, such as sickle fungi. The added bacteria can work in conjunction with the native bacteria to provide reinforcement.

[0040] The method comprises:

[0041] S1: Prepare culture medium.

[0042] The culture medium is used to induce the growth and reproduction of ice-nucleating bacteria, ensuring the initial cell concentration of ice-nucleating bacteria in areas requiring permafrost reinforcement. The formula is: 3g beef extract, 10g peptone, 5g sodium chloride, 1000mL distilled water, pH 7.0, sterilize at 121°C for 15 minutes, and cool until ready for use.

[0043] Other types of culture media such as KB medium or NB medium can also be selected to culture ice nucleation-active bacteria.

[0044] A survey on the acidity and alkalinity of permafrost shows that the pH value of permafrost on the Qinghai-Tibet Plateau is 8.0-9.0, the pH value of permafrost in Heilongjiang is 5.0-9.0, the pH value of permafrost in the Arctic is 5.6-7.0, and the pH value of permafrost in Antarctica is 7.8-9.8, which are close to the pH value of permafrost suitable for the growth of ice-nucleating active bacteria (5.0-9.0).

[0045] S2: Cultivate ice nucleation-active bacteria using culture medium.

[0046] The ice nucleation active bacteria is Pseudomonas syringae, which is cultured at 30°C for 48-72 hours. After the culture is completed, the bacteria is stored in a constant temperature and humidity chamber at 4°C for later use.

[0047] In addition, type I ice nucleation-active bacteria such as Pseudomonas antarctica and Pseudomonas borealis may also be used.

[0048] S3: Obtain ice nucleation active bacterial solution.

[0049] After culturing ice nucleation-active bacteria in a culture medium, an ice nucleation-active bacteria solution can be obtained by diluting with water to control the bacterial content in the solution.

[0050] When the ice-nucleating bacteria solution is actually used in frozen soil, the amount of ice-nucleating bacteria solution required is estimated based on the volume of the reinforced area. This is usually determined by the thickness of the active layer in the reinforced area and the upper surface area of ​​the reinforced area. The volume of the reinforced area is calculated by multiplying the active layer thickness by the upper surface area. For example, the concentration of Pseudomonas syringae in 1000 cubic centimeters of frozen soil is 1g / L.

[0051] In addition, substances that promote ice nucleation activity may be added to the ice nucleation active bacteria solution, including glucose, glycerol, or citric acid. For example, glycerol may be added to the ice nucleation active bacteria solution in an amount of 0.5% to 1.2% of the volume of the ice nucleation active bacteria solution.

[0052] S4: Injecting the ice nucleation active bacteria solution into the high-temperature frozen soil in the high-temperature frozen soil foundation area that needs to be reinforced.

[0053] Injecting the ice-nucleating bacteria solution into high-temperature frozen soil can be done with a delivery device. This device consists of a flower-shaped tube inserted into the soil. The tube has seepage holes in its sidewalls and is connected to an infusion tube at the top. The solution is introduced into the tube through the infusion tube and seeps out through the seepage holes into the frozen soil. In areas of high-temperature frozen soil requiring reinforcement, injection points can be evenly distributed as needed to ensure uniform distribution of the ice-nucleating bacteria within the soil.

[0054] S5: Ice nucleation-active bacteria grow and reproduce in high-temperature permafrost.

[0055] Since the ice nucleation active bacteria solution contains other nutrients, it can also promote the growth and reproduction of native ice nucleation active bacteria and ice nucleation active fungi.

[0056] S6: When ice nucleation-active bacteria grow and accumulate to a certain number on the surface of soil particles, that is, when a certain cell concentration is reached in the reinforced area, they will begin to exert their ice-forming properties, and by increasing the freezing temperature of unfrozen water in the frozen soil, promote the formation of ice crystals at a higher temperature.

[0057] Ice nucleation active proteins arrange water molecules into ice-like lattices, providing a template for the growth of ice in high-temperature permafrost, raising the freezing point of unfrozen water in high-temperature permafrost in a short period of time, thereby freezing the unfrozen water in the high-temperature permafrost and strengthening the high-temperature permafrost foundation.

[0058] Furthermore, to improve the controllability of the method, moisture sensors were placed within the permafrost where the ice-nucleating bacteria solution was injected. These sensors monitored the unfrozen water content of the permafrost in real time. If the unfrozen water content exceeded the local moisture content allowable range, additional ice-nucleating bacteria solution was injected. If the unfrozen water content increased, indicating a decrease in ice content, the injection rate of the ice-nucleating bacteria solution should be increased to promote ice crystal growth. If the unfrozen water content decreased, indicating an increase in ice content, the injection rate should be reduced or the injection should be stopped.

[0059] The process of obtaining the local allowable range of moisture content is as follows: drilling holes on-site in the high-temperature frozen soil foundation area that needs to be reinforced and collecting frozen soil samples to measure the natural moisture content of the frozen soil samples; making reshaped specimens in the laboratory and obtaining the optimal moisture content of the reshaped specimens through compaction tests; obtaining the most unfavorable moisture content of the reshaped specimens through shear tests; and obtaining the local allowable range of moisture content through the natural moisture content, optimal moisture content, and most unfavorable moisture content.

[0060] Temperature sensors can also be placed around the moisture sensors to monitor the temperature of the permafrost in real time. If the temperature of the permafrost in the reinforced area drops, it indicates that sufficient ice has formed in the permafrost, and the supply of ice nucleation solution needs to be stopped.

[0061] In the above method, the ice-nucleating bacteria contained in the ice-nucleating bacteria solution are living bacteria that continue to grow and reproduce after entering frozen soil. However, this method can also directly use freeze-dried ice-nucleating bacteria powder to obtain the ice-nucleating bacteria solution, leveraging the ice nucleation proteins already present in the freeze-dried ice-nucleating bacteria powder. This method is less expensive for short-term treatment.

[0062] The method of the present invention has the following characteristics and advantages:

[0063] 1. The present invention differs from the previous physical cooling method in its approach to frozen soil reinforcement:

[0064] Previous physical cooling methods for actively cooling and protecting frozen soil were based on three principles: extracting heat from the frozen soil, dissipating heat from the frozen soil, or isolating external heat. However, this invention does not rely on cooling to maintain ice solidification in frozen soil. Instead, it adapts to high-temperature frozen soil environments, encouraging unfrozen water in the frozen soil to freeze at high temperatures, providing biological ice nuclei for the frozen soil and thus ensuring its strength.

[0065] 2. The impact of this invention is different from that of previous chemical methods for consolidating frozen soil:

[0066] Chemical reinforcement of frozen soil is highly polluting, destructive and disturbing to the frozen soil environment. The ice nucleation-active bacteria used in the present invention exist in the frozen soil and are themselves ice nuclei, which will not pollute the frozen soil environment. In addition, there are a large number of native ice nucleation-active bacteria and fungi in the frozen soil, indicating that the frozen soil environment is suitable for the reproduction and growth of ice nucleation-active bacteria, which has a positive effect on the reinforcement effect.

[0067] 3. The controllability of the present invention is different from that of previous frozen soil reinforcement measures:

[0068] Both physical and chemical reinforcement methods lack controllability. The present invention measures the moisture content of frozen soil in real time, thereby understanding the amount of unfrozen water within the soil. This information allows the injection of ice-nucleating bacteria solution to be adjusted accordingly, thereby regulating the amount of ice formed within the frozen soil, significantly improving controllability.

[0069] 4. The impact of the present invention on surrounding projects is different from that of previous physical cooling and chemical reinforcement measures:

[0070] Previous reinforcement measures have caused significant thermal disturbances to other structures within the same project corridor, impacting the stability of other infrastructure during service. The ice-nucleating bacteria used in this invention not only reinforce existing structures, but also strengthen structures in adjacent high-temperature permafrost zones.

[0071] The method of the present invention can not only be used to reinforce frozen soil foundations, but also be used to control changes in frozen soil appearance caused by frozen soil degradation, and is of great significance to the protection of frozen soil environments.

[0072] Example:

[0073] The technical solution of the present invention is further described in detail below through specific embodiments:

[0074] Due to warming temperatures or human activities, ice crystals in permafrost are melting. Thaw-subsidence hazards such as landslides and collapses, as well as phenomena such as thaw lakes and surface fluctuations, are becoming more pronounced in high-temperature permafrost areas, seriously impacting engineering construction and the permafrost environment. By introducing a Pseudomonas syringae solution into the area to be reinforced, allowing it to flow and diffuse within the soil particles, when the soil particles absorb and accumulate a certain level of Pseudomonas syringae—that is, when the number of Pseudomonas syringae in the reinforced area reaches a certain cell concentration—Pseudomonas syringae can restructure water molecules, thereby raising the freezing point of unfrozen water and promoting the formation of ice crystals in the high-temperature permafrost environment. The Pseudomonas syringae themselves act as ice nuclei and ice embryos, causing ice to accumulate on their surfaces. This ultimately promotes the growth and expansion of ice crystals in the high-temperature permafrost, increases the ice bonding between permafrost particles, enhances the strength of the permafrost, and effectively improves the bearing capacity of the permafrost foundation.

[0075] This embodiment can achieve high-temperature frozen soil foundation reinforcement. By setting up an indoor frozen soil reinforcement test, test data on the reinforcement of high-temperature frozen soil with Pseudomonas syringae (purchased from Shanghai Guyan Industrial Co., Ltd.) was obtained. In this test, the high-temperature frozen soil temperature was selected as -1°C, the frozen soil moisture content was 20%, and the concentration of the Pseudomonas syringae solution was 1g / L. Frozen soil samples of the control group and the control group frozen soil samples with 1g / L Pseudomonas syringae solution added were prepared. Frozen soil shear tests were performed under normal pressures of 100kPa, 200kPa, 300kPa, and 400kPa, respectively, to obtain the frozen soil shear strength and shear strength parameters.

[0076] Table 1 Comparison of frozen soil strength data between control group and comparison group

[0077]

[0078] As shown in Table 1, the addition of Pseudomonas syringae ice-nucleating bacteria increased the shear strength of high-temperature frozen soil, especially when the normal pressure was 100 kPa. This indicates that ice-nucleating bacteria are most effective in reinforcing high-temperature frozen soil foundations with small vertical loads. This corresponds to practical engineering applications such as shallow foundations in permafrost areas and the upper surface and active layers of high-temperature frozen soil that are susceptible to external temperature rise and thermal erosion.

[0079] The relationship curve between shear strength and normal pressure is plotted with the shear strength as the ordinate and the normal pressure as the abscissa in Table 1. Figure 1 Linear fitting of the scattered points shows that the addition of Pseudomonas syringae solution increases the cohesion of the high-temperature frozen soil from 71.5 kPa to 154.4 kPa, and the internal friction angle increases from 25.9° to 28.4°. It can be seen that the Pseudomonas syringae solution increases the cohesion of the high-temperature frozen soil by nearly 3 times. The increase in the shear strength of the high-temperature frozen soil is attributed to the increase in cohesion. The reason is that the addition of Pseudomonas syringae solution to the high-temperature frozen soil not only provides more ice nuclei for the formation of ice crystals in the frozen soil, but also increases the freezing point of unfrozen water in the frozen soil sample at -1°C. As a result, the number of ice crystals in the frozen soil with the addition of Pseudomonas syringae solution is greater than that without the addition of Pseudomonas syringae solution at the same temperature. More ice crystals provide greater ice cementation strength. For frozen soil, ice cementation strength contributes most to the cohesion of frozen soil. Therefore, the cohesion between the particles of the high-temperature frozen soil is increased, thereby increasing the shear strength of the high-temperature frozen soil.

[0080] It can be seen that the use of Pseudomonas syringae solution to reinforce high-temperature frozen soil foundations is feasible and has a good reinforcement effect.

[0081] The above examples are used to illustrate the present invention, which are only used to help understand the present invention and are not intended to limit the present invention. Those skilled in the art can make several simple deductions, modifications or substitutions based on the concept of the present invention.

Claims

1. A high-temperature frozen soil foundation reinforcement method based on ice nucleation-active bacteria, characterized by: The method comprises: Prepare culture medium; Cultivating ice nucleation-active bacteria using culture medium; Obtain ice nucleation active bacterial solution; Injecting ice nucleation active bacterial solution into the high temperature frozen soil in the high temperature frozen soil foundation area that needs to be reinforced; Ice nucleation-active bacteria grow and multiply in high-temperature frozen soil; The ice nucleation-active protein anchored in the outer membrane of ice-nucleation-active bacteria provides a template for the growth of ice in high-temperature permafrost. By raising the freezing point of unfrozen water in high-temperature permafrost, the unfrozen water in high-temperature permafrost freezes, thereby strengthening the high-temperature permafrost foundation.

2. The method according to claim 1, wherein: The formula of the culture medium is: Beef extract 3g, peptone 10g, sodium chloride 5g, distilled water 1000mL.

3. The method according to claim 2, wherein: The pH value of the culture medium is 7.

0.

4. The method according to claim 3, wherein: The ice nucleation active bacteria are selected from Pseudomonas syringae, Pseudomonas antarctica, and Pseudomonas polaris.

5. The method according to claim 4, characterized in that: Glycerol is added to the ice nucleation active bacterial solution in an amount of 0.5% to 1.2% of the volume of the ice nucleation active bacterial solution.

6. The method according to claim 5, characterized in that: The method further comprises: Deploy moisture sensors in high-temperature frozen soil injected with a solution of ice-nucleating bacteria; Use moisture sensors to monitor the unfrozen water content of high-temperature frozen soil in real time; If the unfrozen water content of the high-temperature frozen soil is higher than the local moisture content allowable range, ice nucleation active bacterial solution will be injected.

7. The method according to claim 6, characterized in that: The process of obtaining the allowable range of local moisture content is as follows: Drill holes on-site in the high-temperature frozen soil foundation area that needs to be reinforced and collect frozen soil samples to measure the natural moisture content of the frozen soil samples; The reshaped specimens were made in the laboratory and the optimal moisture content of the reshaped specimens was obtained through compaction tests; Through shear test, the most unfavorable moisture content of the reshaped specimen is obtained; The local allowable moisture content range is obtained through the natural moisture content, optimal moisture content and most unfavorable moisture content.

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