Permafrost railway roadbed structure design method based on adsorption type all-season hot rod

Abstract

The invention discloses a permafrost railway roadbed structure design method based on an adsorption type all-season hot rod. The permafrost railway roadbed structure design method comprises the steps that the solar radiation intensity and the annual average ground temperature distribution of permafrost in a target area are evaluated; measuring frozen soil active layer thickness, frozen soil ice content space distribution and frozen soil thermophysical parameters; establishing a refrigeration power model of the adsorption type hot rod, and calibrating the refrigeration efficiency of the adsorption type hot rod; according to the calibrated refrigeration efficiency of the adsorption type hot rod, designing layout parameters of the adsorption type all-season hot rod in the roadbed; according to temperature rise prediction, the refrigeration power model is corrected, and parameters of the adsorption type all-season hot rod are dynamically adjusted; and carrying out a hot rod roadbed prototype test, and carrying out dynamic regulation and control on parameters of the adsorption type all-season hot rod. The limitation that a traditional siphon type hot rod only works in winter is broken through, it is ensured that the roadbed keeps the low-temperature heat dissipation capacity under different climate conditions all the year round, and the heat stability of the railway roadbed in the permafrost region is greatly improved.

Description

Technical Field

[0001] The present invention relates to the technical field of frozen soil subgrade design, and particularly to a design method for a multi-year frozen soil railway subgrade structure based on an adsorption type all-season heat pipe. Background Art

[0002] When building infrastructure such as railways and highways in permafrost regions, how to ensure the thermal stability of the frozen soil layer has always been a key technical problem. With the intensification of the global warming trend, the problem of permafrost degradation has become increasingly serious, resulting in problems such as subgrade settlement, structural deformation, misalignment of bridge piers and abutments, and potential safety hazards in line operation.

[0003] In recent years, with the intensification of permafrost degradation and frequent occurrence of subgrade diseases, the multi-season or even all-year regulation type heat pipe technology has become a research hotspot. The research and development of high-efficiency working fluids and structurally optimized heat pipes have improved the refrigeration power; intelligent control type heat pipes can automatically adjust the operating state according to the ground temperature change; a thermal control system that can adapt to the trend of climate warming has emerged, such as the adsorption type heat pipe technology; the design method of the thermal regulation model combining remote sensing + on-site monitoring + numerical simulation has developed towards the direction of "data-driven + model prediction"; the transition from passive regulation to active regulation, such as active thermal control devices driven by solar energy, adsorption materials, etc.

[0004] Currently, the common thermal stability control technologies for permafrost subgrades mainly have the following objective technical defects: (1) Seasonal operation limitations. The thermosyphon usually only operates in winter and cannot cope with abnormal temperature rises or extreme climate impacts in non-winter seasons, resulting in poor refrigeration timeliness; (2) The operating performance depends on the environmental temperature difference. The refrigeration effect is restricted by the external air temperature, and the heat pipe shows instability in abnormal climate years and lacks dynamic adaptability; (3) The design of thermophysical parameters lacks a dynamic feedback mechanism. Most designs are based on static thermal parameters and do not fully consider the impacts caused by the evolution of permafrost over time and climate change; (4) There is a lack of a high-precision parameter layout model. The traditional heat pipe layout scheme is mostly based on empirical values, ignoring factors such as local ground temperature changes and solar radiation differences, and it is difficult to achieve precise design; (5) The deviation between the design goal and the measured operating data is large. The prototype test often fails to provide a closed-loop feedback and does not form an automatic regulation mechanism. There may be a large difference between the design goal and the actual operating results. Summary of the Invention

[0005] In view of this, the purpose of the embodiments of the present invention is to provide a design method for a multi-year frozen soil railway subgrade structure based on an adsorption type all-season heat pipe, which can break through the limitation that the traditional siphon type heat pipe only works in winter, ensure that the subgrade maintains low-temperature heat dissipation capacity under different climate conditions throughout the year, and greatly improve the thermal stability of the railway subgrade in permafrost regions.

[0006] A design method for a multi-year frozen soil railway subgrade structure based on an adsorption type all-season heat pipe includes:

[0007] Based on high - resolution remote sensing data and on - site ground temperature monitoring, evaluate the solar radiation intensity and the annual average ground temperature distribution of permafrost in the target area.

[0008] Through geological drilling and geophysical prospecting, determine the thickness of the active layer of permafrost, the spatial distribution of ice content in permafrost, and the thermophysical parameters of permafrost.

[0009] According to the solar radiation intensity and the thermophysical parameters of permafrost, establish a refrigeration power model of the adsorption heat pipe, and calibrate the refrigeration efficiency of the adsorption heat pipe.

[0010] According to the calibrated refrigeration efficiency of the adsorption heat pipe, design the layout parameters of the adsorption all - season heat pipe in the subgrade.

[0011] According to the warming prediction, correct the refrigeration power model and dynamically adjust the parameters of the adsorption all - season heat pipe.

[0012] Conduct a prototype test of the heat pipe subgrade, collect data in real - time, compare the measured ground temperature with the designed target value. If the deviation exceeds the preset range, dynamically adjust the parameters of the adsorption all - season heat pipe until the permafrost thermal stability requirements are met.

[0013] In a preferred embodiment of the present invention, in the above - mentioned design method of the permafrost railway subgrade structure based on the adsorption all - season heat pipe, the evaluation of the solar radiation intensity and the annual average ground temperature distribution of permafrost based on high - resolution remote sensing data and on - site ground temperature monitoring includes:

[0014] Obtain high - resolution multi - spectral remote sensing images of the target area, and extract surface cover type and surface temperature spatial distribution data.

[0015] Layout on - site ground temperature observation boreholes, install temperature - measuring elements in the boreholes, conduct long - term continuous ground temperature monitoring at different depths and positions, record the temperature changes in each season, and obtain permafrost seasonal ground temperature data.

[0016] Through remote sensing image interpretation technology, identify the differences in solar radiation absorption of different geomorphic units in the high - resolution multi - spectral remote sensing images, establish a solar radiation intensity distribution map, and the geomorphic units include at least one of the shady slope, sunny slope, and vegetation - covered area.

[0017] Perform spatial interpolation on the surface temperature spatial distribution data and the permafrost seasonal ground temperature data to generate a three - dimensional distribution model of the annual average ground temperature of permafrost.

[0018] Overlay the solar radiation intensity distribution map and the three - dimensional distribution model of the annual average ground temperature of permafrost to establish a radiation - ground temperature correlation matrix, and divide different thermal stability regions.

[0019] In a preferred embodiment of the present invention, in the above method for designing the permafrost railway subgrade structure based on the adsorption-type all-season heat rod, after establishing the radiation ground temperature correlation matrix, it further includes:

[0020] Substitute the measured data of the surface radiation flux into the solar radiation intensity distribution map to calibrate the model parameters.

[0021] Its technical effect is as follows: Through multi-spectral remote sensing images, the surface cover type and temperature distribution can be quickly obtained at the kilometer scale, making up for the spatial blind area of single-point borehole monitoring, and providing macroscopic boundary conditions for subsequent three-dimensional temperature field modeling; Install multi-depth temperature measuring elements in on-site boreholes to obtain the temperature curve of seasonal frozen soil, and fuse it with the surface temperature data retrieved by remote sensing through spatial interpolation to generate a more realistic three-dimensional annual average ground temperature distribution model of "surface - active layer - permafrost", greatly improving the accuracy and reliability of temperature field description; By interpreting different geomorphic units with remote sensing images, including the albedo and thermal response differences of shady slopes, sunny slopes, and vegetation areas, draw the regional solar radiation intensity distribution map, providing accurate input for the solar energy driving term in the refrigeration power model, and avoiding the errors caused by empirical estimation.

[0022] In a preferred embodiment of the present invention, in the above method for designing the permafrost railway subgrade structure based on the adsorption-type all-season heat rod, the determination of the thickness of the frozen soil active layer, the spatial distribution of ice content in frozen soil, and the thermophysical parameters of frozen soil through geological drilling and geophysical exploration includes:

[0023] Use high-density electrical method and ground penetrating radar to conduct grid scanning on the target area to delineate the area where the thickness of the active layer changes.

[0024] Layout verification boreholes in the area where the thickness of the active layer changes, and the depth of the boreholes penetrates the permafrost to detect the thickness of the frozen soil active layer .

[0025] Extract frozen soil samples from the boreholes and use the volumetric method to measure the total water content.

[0026] Combine the borehole data with the empirical formula of ice content in resistivity of geophysical exploration to generate a three-dimensional model of the spatial distribution of ice content in frozen soil.

[0027] Use a thermal conductivity meter to calculate the thermal conductivity k of the frozen soil sample, measure the specific heat capacity of the frozen soil sample and calculate the volumetric heat capacity C.

[0028] Its technical effects are as follows: The high-density electrical method and the geological radar grid scanning can quickly identify the areas with changing active layer thickness over a large range, verify the depth of the borehole actually measured through the permafrost, ensure the accuracy of the active layer thickness data, and provide a reliable basis for the subsequent design of the evaporation section length and the burial depth of the heat pipe; construct a three-dimensional spatial distribution model of ice content, visually reflect the high-ice and low-ice areas, and provide a true latent heat absorption distribution for the calculation of "heat load → refrigeration demand".

[0029] In a preferred embodiment of the present invention, in the above-mentioned design method of the permafrost railway subgrade structure based on the adsorption-type all-season heat pipe, the establishment of the refrigeration power model of the adsorption-type heat pipe according to the solar radiation intensity and the permafrost thermophysical parameters, and the calibration of the refrigeration efficiency of the adsorption-type heat pipe include:

[0030] According to the solar radiation intensity distribution map, extract the total horizontal radiation amount S of the target area.

[0031] Calculate the total cooling load according to the permafrost thermophysical parameters , where represents the cooling capacity required to reduce the permafrost from the initial temperature to the target temperature , represents the continuous cooling capacity to resist climate warming, is the soil mass within the refrigeration range, is the heat transfer coefficient, is the characteristic length, is the Nusselt number, is the temperature difference between the air temperature and the target ground temperature, is the annual refrigeration duration.

[0032] Establish the formula for the photothermal conversion efficiency of the adsorption-type heat pipe , where is the nominal efficiency, is the temperature decay coefficient, is the temperature of the heat collection section, is the ambient temperature.

[0033] Establish the refrigeration power model of the adsorption-type heat pipe , where is the effective area of the heat collection section, is the heat loss power, is the pipe heat transfer coefficient, is the surface area of the evaporation section, is the permafrost ground temperature.

[0034] Calculate the annual refrigeration capacity of the heat pipe , according to the total cooling load and the annual refrigeration capacity of the heat pipe The calculation results are used to calibrate the refrigeration efficiency of the adsorption heat pipe .

[0035] In a preferred embodiment of the present invention, in the above method for designing the permafrost railway subgrade structure based on the adsorption all-season heat pipe, the refrigeration efficiency of the adsorption heat pipe is calibrated After that, the refrigeration efficiency is maintained To ensure redundant refrigeration capacity.

[0036] If the refrigeration efficiency , then the heat collection area is optimized and increased, the heat loss is reduced, and the refrigerant flow rate is adjusted in sequence.

[0037] The increase in the heat collection area includes expanding the effective area of the heat collection section and improving the nominal efficiency .

[0038] The reduction of heat loss uses a vacuum insulation pipe to reduce the heat transfer coefficient of the pipeline .

[0039] The adjustment of the refrigerant flow rate uses a valve to control the flow rate, so that the temperature of the heat collection section is reduced to below.

[0040] Its technical effects are as follows: By inputting the total horizontal radiation S of the target area and the in-situ permafrost thermophysical parameters into the model, the total cooling load of the two parts of "cooling cooling capacity" and "continuous cooling capacity" is accurately calculated, avoiding the problems of over-conservatism or insufficient configuration in traditional empirical estimation; The efficiency calibration is completed by comparing the actual total cooling load with the annual refrigeration capacity of the heat pipe, and a certain redundancy coefficient is retained on this basis, so that even in the event of sudden changes in ambient temperature or light attenuation, the system still has excess refrigeration capacity, ensuring the safety margin of permafrost thermal stability; By increasing the effective heat absorption area of the heat collection section and using high-efficiency heat collection materials / structures, the photothermal conversion rate is improved, vacuum insulation technology is used on the outer layer of the pipeline, the heat transfer coefficient of the pipeline is significantly reduced, the heat loss in the middle is reduced, and the temperature of the evaporation section and the heat collection section is controlled in real time by adjusting the flow valve, so that the system always operates at the optimal temperature difference, taking into account the refrigeration intensity and energy consumption efficiency, and optimizing and improving the overall efficiency in multiple dimensions; When it is monitored or predicted that the refrigeration efficiency drops to the preset threshold, the heat collection area can be increased, the insulation can be strengthened, and the flow rate can be adjusted in sequence according to the priority, forming a multi-level response strategy from passive (hardware optimization) to active (operating parameter adjustment), improving the stable operation ability of the system under extreme climate conditions such as rainy days, extremely cold or high temperatures.

[0041] In a preferred embodiment of the present invention, in the above method for designing the permafrost railway subgrade structure based on the adsorption all-season heat pipe, the layout parameters of the adsorption all-season heat pipe in the subgrade designed according to the calibrated refrigeration efficiency of the adsorption heat pipe include:

[0042] Based on the calibrated coefficient of refrigerating efficiency calculate the effective refrigerating radius of a single heat pipe , where is the annual refrigerating capacity of a single heat pipe is the annual average ground temperature difference

[0043] According to the effective refrigerating radius calculate the spacing between adjacent adsorption heat pipes, so that the longitudinal spacing , and the transverse spacing .

[0044] According to the thickness of the active layer of frozen soil calculate the installation inclination angle of the adsorption heat pipe , where is the length of the evaporation section of the heat pipe means that the evaporation section needs to penetrate the active layer and extend 1.5 m below the upper limit of frozen soil

[0045] For the stress concentration area at the toe of the subgrade slope, the adsorption heat pipes are arranged in a denser pattern, and the transverse spacing is compressed to 0.8 .

[0046] Conduct collaborative optimization of the heat pipe subgrade to make the coverage rate of the adsorption heat pipe , where is the projected area of the subgrade, and n is the number of heat pipes

[0047] In a preferred embodiment of the present invention, in the above-mentioned design method of the permafrost railway subgrade structure based on the adsorption all-season heat pipe, the length of the evaporation section of the heat pipe is determined according to the refrigerating efficiency classification When the refrigerating efficiency classification is level one, the length of the evaporation section of the heat pipe When the refrigerating efficiency classification is level two, the length of the evaporation section of the heat pipe is within When the refrigerating efficiency classification is level three, the length of the evaporation section of the heat pipe .

[0048] The refrigerating efficiency classification is assigned according to the permafrost thermal stability index When the permafrost thermal stability index , the refrigerating efficiency classification is level one. When the permafrost thermal stability index , the refrigerating efficiency classification is level two. When the permafrost thermal stability index , the refrigerating efficiency classification is level three

[0049] Its technical effects are as follows: Calculate the spacing according to the effective cooling radius of a single heat pipe, so that the cooling influence areas of adjacent heat pipes overlap by ≥ 30%, avoiding the occurrence of cold islands or blind spots, and ensuring the uniformity and continuity of the overall temperature field of the subgrade; For weak parts with stress concentration such as the toe of the slope, compress the lateral spacing to 0.8 Re, so that the cooling density in the key area is higher, thereby effectively suppressing the risk of frozen soil deformation or settlement; Automatically calculate the optimal installation inclination according to the thickness of the active layer of the frozen soil and the length of the evaporation section, so that the evaporation section can not only penetrate to the bottom of the active layer, but also maintain a burial depth margin of ≥ 1.5 m, ensuring that the ground temperature cooling effect is both deep and stable; Through overall collaborative optimization, dynamically adjust the number n of heat pipes to meet the set coverage rate requirements, while ensuring the thermal control performance, avoiding cost waste caused by excessive layout.

[0050] In a preferred embodiment of the present invention, in the above-mentioned design method of the permafrost railway subgrade structure based on the adsorption type all-season heat pipe, the modifying the refrigeration power model according to the warming prediction and dynamically adjusting the parameters of the adsorption type all-season heat pipe include:

[0051] Extract the annual temperature increase rate in the next 50 years , and update the continuous cooling capacity to resist climate warming , where is the design life of the adsorption type heat pipe.

[0052] Update the photothermal conversion efficiency formula of the adsorption type heat pipe , where is the current ambient temperature, represents the cumulative temperature increase amplitude.

[0053] Update the refrigeration power model of the adsorption type heat pipe .

[0054] Update the effective cooling radius , and adjust the spacing between the adsorption type heat pipes according to the updated effective cooling radius .

[0055] Its technical effects are as follows: Introduce the current ambient temperature and the cumulative temperature increase amplitude terms into the photothermal conversion efficiency formula, so that the calculation of the photothermal adsorption and refrigeration efficiency of the heat pipe can reflect the actual climate degradation situation, enhancing the timeliness and reliability of the model; Dynamically update the refrigeration power model and the effective cooling radius, and adjust the heat pipe spacing accordingly, realizing an active maintenance strategy of "compensating for the spacing as the performance degrades and increasing or decreasing the number of pipes as the cooling capacity changes", avoiding refrigeration blind spots or efficiency decay caused by climate warming; Through multiple model corrections and layout fine-tuning during the design period, convert non-one-time excessive layout or frequent large-scale maintenance into data-based local adjustments, reducing the overall construction and operation and maintenance investment, and realizing the maximization of long-term economic benefits.

[0056] In a preferred embodiment of the present invention, in the above-mentioned design method for the permafrost railway subgrade structure based on the adsorption-type all-season heat pipe, the heat pipe subgrade prototype test is carried out, data is collected in real time, the measured ground temperature is compared with the design target value. If the deviation exceeds the preset range, the parameters of the adsorption-type all-season heat pipe are dynamically adjusted until the permafrost thermal stability requirements are met, including:

[0057] Select an area with an average annual ground temperature of permafrost as the test site, remove the surface vegetation to the permafrost upper limit, and arrange according to the designed parameters of the adsorption-type all-season heat pipe.

[0058] Lay optical fibers at a depth of 0-5 m below the permafrost upper limit, install layered displacement gauges at the subgrade center line and the slope toe, and install pressure sensors and flow meters at the heat pipes at the same time.

[0059] Carry out multi-load level creep tests, and record ground temperature data, deformation data and heat pipe parameters in real time.

[0060] Calculate the ground temperature deviation , where is the ground temperature data recorded in real time, is the depth, is the time, is the number of temperature measurement points. If the ground temperature deviation lasts for 24 hours, it is determined that the deviation exceeds the preset range, and the regulation mechanism is triggered.

[0061] After the regulation mechanism is triggered, adjust the refrigerant flow rate and the spacing between the adsorption-type heat pipes until the permafrost thermal stability requirements are met.

[0062] Its technical effects are as follows: Carry out prototype tests under the on-site conditions where the average annual temperature of permafrost ≥ -0.5 °C, and comprehensively verify the refrigeration effect and construction feasibility of the parameters such as the layout, depth and inclination angle of the heat pipes designed based on the model in the actual permafrost environment; Use multi-dimensional monitoring means such as optical fiber ground temperature sensing, layered displacement gauges, pressure and flow sensors, and synchronously obtain ground temperature, deformation and heat pipe operation status data, providing reliable data support for evaluating the permafrost thermal-mechanical coupling response; Through the 24-hour continuous monitoring of the ground temperature deviation formula, the deviation between the design target and the on-site measurement can be quickly identified, potential thermal instability risks can be pre-warned, and subgrade diseases caused by insufficient burial depth or uneven refrigeration can be avoided; When the deviation exceeds the limit, the system can adjust the refrigerant flow rate and the local heat pipe spacing online, forming a closed loop of "monitoring → determination → regulation → verification", so that the heat pipe system is continuously optimized during operation to ensure that the permafrost thermal stability continuously meets the standards.

[0063] A design system for the permafrost railway subgrade structure based on the adsorption-type all-season heat pipe, which includes:

[0064] A remote sensing and ground temperature data acquisition module, which is used to evaluate the solar radiation intensity and the annual average ground temperature distribution of permafrost in a target area based on high-resolution remote sensing data and on-site ground temperature monitoring.

[0065] A drilling module, which is used to determine the thickness of the active layer of permafrost, the spatial distribution of ice content in permafrost, and the thermophysical parameters of permafrost through geological drilling and geophysical prospecting.

[0066] A refrigeration power model construction module, which is used to establish a refrigeration power model of an adsorption heat pipe according to the solar radiation intensity and the thermophysical parameters of permafrost, and calibrate the refrigeration efficiency of the adsorption heat pipe.

[0067] A heat pipe parameter design module, which is used to design the layout parameters of the adsorption full-season heat pipe in the subgrade according to the calibrated refrigeration efficiency of the adsorption heat pipe.

[0068] A heat pipe parameter adjustment module, which is used to correct the refrigeration power model according to the warming prediction and dynamically adjust the parameters of the adsorption full-season heat pipe.

[0069] An experimental control module, which is used to conduct a prototype test of the heat pipe subgrade, collect data in real time, compare the measured ground temperature with the designed target value. If the deviation exceeds the preset range, the parameters of the adsorption full-season heat pipe are dynamically adjusted until the permafrost thermal stability requirements are met.

[0070] The beneficial effects of the embodiments of the present invention are as follows:

[0071] The adsorption full-season heat pipe of the present invention introduces an adsorption refrigeration cycle and converts solar photothermal energy into active refrigeration capacity. The system includes a heat collection / adsorption section, a condensation section, an evaporation section, etc., and consists of an adsorption pair composed of an adsorbent such as activated carbon or silica gel and a refrigerant such as methanol. During heat collection in the daytime, the adsorbent heats up and desorbs the refrigerant, and the refrigerant vapor liquefies and stores after releasing heat in the condensation section; at night or on cloudy days, the temperature of the adsorbent drops and it re-adsorbs the refrigerant, driving the evaporation section to refrigerate and releasing the ground temperature cold energy to the adsorbent. This photothermal-driven adsorption–desorption cycle enables the heat pipe to operate throughout the four seasons: obtaining refrigeration using solar energy during the day or in summer, with intermittent refrigeration during the day and continuous adsorption refrigeration at night, and still being able to absorb geothermal heat in winter, and increasing the refrigeration capacity when there is sunlight. Research shows that the dedicated adsorption refrigeration tube can reduce the substrate temperature to about –2.9°C in the experiment, with an average of –1.5°C, effectively protecting the permafrost for many years. The present invention reduces the reflection of the heat collection surface, improves the photothermal utilization rate, enables faster and more complete desorption, overcomes the deficiency that the single-channel adsorption system can only refrigerate at night, and improves the overall energy efficiency of the system.

[0072] Design method for subgrade structure of permafrost railway based on adsorption-type all-season heat pipe. In the face of challenges such as rising air temperature and increasing ice ablation in permafrost regions, the adsorption-type all-season heat pipe can actively respond by adjusting operating parameters. The system can control the working time and refrigeration intensity of the heat pipe according to real-time or predicted climate conditions. For example, it can strengthen the reverse heat transfer in the warm season. Compared with the traditional heat pipe design that only relies on empirical construction, this method estimates the latent heat of permafrost melting through an energy balance model and climate simulation, pre-determines the heat pipe structure and layout spacing, and continuously corrects the model parameters through temperature sensing feedback after construction. This "foresight" design concept enables the layout of the heat pipes to be adjusted according to climate prediction and on-site monitoring results, optimize the layout, adjust the spacing, and increase the number of heat pipes to ensure the thermal stability of permafrost. Description of the Drawings

[0073] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as limiting the scope. For those of ordinary skill in the art, other related drawings can be obtained based on these drawings without creative efforts.

[0074] Figure 1 It is a flow chart of the design method for subgrade structure of permafrost railway based on adsorption-type all-season heat pipe of the present invention. Detailed Embodiments

[0075] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. Usually, the components of the embodiments of the present invention described and shown in the drawings here can be arranged and designed in various different configurations.

[0076] Please refer to Figure 1, the first embodiment of the present invention provides a design method for a permafrost railway subgrade structure based on an adsorption-type all-season heat pipe, which includes: evaluating the solar radiation intensity and the annual average ground temperature distribution of the permafrost in the target area based on high-resolution remote sensing data and on-site ground temperature monitoring; determining the thickness of the active layer of the permafrost, the spatial distribution of the ice content in the permafrost, and the thermophysical parameters of the permafrost through geological drilling and geophysical exploration; establishing a refrigeration power model of the adsorption-type heat pipe according to the solar radiation intensity and the thermophysical parameters of the permafrost, and calibrating the refrigeration efficiency of the adsorption-type heat pipe; designing the layout parameters of the adsorption-type all-season heat pipe in the subgrade according to the calibrated refrigeration efficiency of the adsorption-type heat pipe; correcting the refrigeration power model according to the warming prediction, and dynamically adjusting the parameters of the adsorption-type heat pipe; conducting a prototype test of the heat pipe subgrade, collecting data in real time, comparing the measured ground temperature with the designed target value, and if the deviation exceeds the preset range, dynamically regulating the parameters of the adsorption-type heat pipe until the permafrost thermal stability requirements are met.

[0077] Among them, the evaluation of the solar radiation intensity and the annual average ground temperature distribution of the permafrost in the target area based on high-resolution remote sensing data and on-site ground temperature monitoring includes: obtaining high-resolution multi-spectral remote sensing images of the target area, and extracting data on the spatial distribution of surface cover types and surface temperatures; arranging on-site ground temperature observation boreholes, installing temperature measurement elements in the boreholes, the temperature measurement elements using thermistors or platinum resistance temperature sensors, conducting long-term continuous ground temperature monitoring at different depths and positions, recording the temperature changes in each season, and obtaining permafrost seasonal ground temperature data; through remote sensing image interpretation technology, identifying the differences in solar radiation absorption of different geomorphic units in the high-resolution multi-spectral remote sensing images, establishing a solar radiation intensity distribution map, the geomorphic units including at least one of the shaded slope, sunny slope, and vegetation-covered area; spatially interpolating the spatial distribution data of the surface temperature and the permafrost seasonal ground temperature data to generate a three-dimensional distribution model of the annual average ground temperature of the permafrost; superimposing the solar radiation intensity distribution map and the three-dimensional distribution model of the annual average ground temperature of the permafrost to establish a radiation-ground temperature correlation matrix, and dividing different thermal stability regions.

[0078] Among them, after establishing the radiation-ground temperature correlation matrix, it further includes: substituting the measured data of the surface radiation flux into the solar radiation intensity distribution map to calibrate the model parameters.

[0079] Its technical effects are as follows: Through multi-spectral remote sensing images, the surface cover types and temperature distributions can be quickly obtained at the kilometer scale, making up for the spatial blind spots of single-point borehole monitoring and providing macroscopic boundary conditions for subsequent three-dimensional temperature field modeling; Temperature measuring elements with multiple depths are arranged in on-site boreholes to obtain the temperature curves of seasonal frozen soil. By spatially interpolating and fusing with the surface temperature data retrieved by remote sensing, a more realistic three-dimensional annual average ground temperature distribution model of "surface - active layer - permafrost" is generated, greatly improving the accuracy and reliability of temperature field description; Different geomorphic units are interpreted with the help of remote sensing images, including the albedo and thermal response differences of shady slopes, sunny slopes, and vegetation areas, to draw the regional solar radiation intensity distribution map, providing accurate input for the solar energy drive term in the refrigeration power model and avoiding errors caused by empirical estimation.

[0080] Among them, the determination of the thickness of the active layer of frozen soil, the spatial distribution of ice content in frozen soil, and the thermophysical parameters of frozen soil through geological drilling and geophysical exploration include: Conducting grid scanning of the target area using high-density electrical method and ground penetrating radar to delineate the area with variable active layer thickness; Verification boreholes are arranged in the area with variable active layer thickness, and the borehole depth penetrates through the permafrost to detect the thickness of the active layer of frozen soil. ; Frozen soil samples are extracted from the boreholes, and the total water content is measured using the volumetric method; Combining the borehole data with the empirical formula of ice content from geophysical exploration resistivity, a three-dimensional model of the spatial distribution of ice content in frozen soil is generated; The thermal conductivity k of the frozen soil sample is calculated using a thermal conductivity meter, and the specific heat capacity of the frozen soil sample is measured and the volumetric heat capacity C is calculated.

[0081] Its technical effects are as follows: The grid scanning of high-density electrical method and ground penetrating radar can quickly identify the area with variable active layer thickness over a large range, verify the depth of the actual measurement of the verification borehole penetrating through the permafrost, ensure the accuracy of the active layer thickness data, and provide a reliable basis for the design of the evaporation section length and burial depth of subsequent heat pipes; Constructing a three-dimensional spatial distribution model of ice content can visually reflect the high-ice and low-ice areas, providing a real latent heat absorption distribution for the calculation of "heat load → refrigeration demand".

[0082] Among them, establishing the refrigeration power model of the adsorption heat pipe and calibrating the refrigeration efficiency of the adsorption heat pipe according to the solar radiation intensity and the thermophysical parameters of frozen soil include: Extracting the total horizontal radiation amount S of the target area according to the solar radiation intensity distribution map; Calculating the total cooling load according to the thermophysical parameters of frozen soil. , where represents the cooling capacity required to reduce the frozen soil from the initial temperature to the target temperature , represents the continuous cooling capacity to resist climate warming, is the mass of the soil body within the refrigeration range, is the heat transfer coefficient, is the characteristic length, is the Nusselt number, is the temperature difference between the air temperature and the target location, is the annual cooling duration; establish the formula for the photothermal conversion efficiency of the adsorption heat pipe , where is the nominal efficiency, with a value range of 0.35 - 0.45, determined according to the heat pipe model, is the temperature attenuation coefficient, taking 0.0025 / °C, is the temperature of the heat collection section, is the ambient temperature; establish the refrigeration power model of the adsorption heat pipe , where is the effective area of the heat collection section, is the heat loss power, is the heat transfer coefficient of the pipeline, is the surface area of the evaporation section, is the permafrost temperature; calculate the annual cooling capacity of the heat pipe , according to the total cooling load and the calculated result of the annual cooling capacity of the heat pipe , calibrate the refrigeration efficiency of the adsorption heat pipe .

[0083] Among them, after calibrating the refrigeration efficiency of the adsorption heat pipe , maintain the refrigeration efficiency to ensure redundant refrigeration capacity; if the refrigeration efficiency , then sequentially optimize and increase the heat collection area, reduce the heat loss, and adjust the refrigerant flow rate; the increase in the heat collection area includes expanding the effective area of the heat collection section and increasing the nominal efficiency ; the reduction of heat loss uses vacuum insulation pipes to reduce the heat transfer coefficient of the pipeline ; the adjustment of the refrigerant flow rate uses a valve to control the flow rate, so that the temperature of the heat collection section is reduced to below.

[0084] Its technical effects are as follows: By inputting the total horizontal radiation amount S of the target area and the in-situ frozen soil thermophysical parameters into the model, the total cooling load of two parts, namely "cooling capacity" and "continuous cooling capacity", is accurately calculated, avoiding the problems of over-conservatism or insufficient configuration in traditional empirical estimation; The performance calibration is completed by comparing the actual total cooling load with the annual cooling capacity of the heat pipe, and a certain redundancy coefficient is reserved on this basis, so that even in the case of sudden environmental temperature changes or light attenuation, the system still has excess refrigeration capacity to ensure the safety margin of the thermal stability of permafrost; By increasing the effective heat absorption area of the heat collection section and using high-efficiency heat collection materials / structures, the photothermal conversion rate is improved, and vacuum insulation technology is adopted on the outer layer of the pipeline, significantly reducing the heat transfer coefficient of the pipeline and reducing the heat loss in the middle. By adjusting the flow valve to control the temperature of the evaporation section and the heat collection section in real time, the system always operates at the optimal temperature difference, taking into account both the refrigeration intensity and the energy consumption efficiency, and multi-dimensionally optimizing and improving the overall performance; When it is monitored or predicted that the refrigeration efficiency drops to the preset threshold, the heat collection area can be increased, the insulation can be strengthened, and the flow can be adjusted in sequence according to the priority, forming a multi-level response strategy from passive (hardware optimization) to active (operating parameter adjustment), improving the stable operation ability of the system under extreme climate conditions such as rainy days, extremely cold or high temperatures.

[0085] Among them, the layout parameters of the adsorption full-season heat pipe in the subgrade designed according to the calibrated refrigeration efficiency of the adsorption heat pipe include: Based on the calibrated refrigeration efficiency coefficient , calculate the effective refrigeration radius of a single heat pipe , where is the annual cooling capacity of a single heat pipe, is the annual average ground temperature difference; According to the effective refrigeration radius , calculate the spacing between adjacent adsorption heat pipes, so that the longitudinal spacing , the transverse spacing , so that the overlapping rate of the refrigeration ranges of adjacent heat pipes ≥ 30%; According to the thickness of the active layer of frozen soil, calculate the installation inclination angle of the adsorption heat pipe, where is the length of the evaporation section of the heat pipe, indicates that the evaporation section needs to penetrate the active layer and extend 1.5 m below the permafrost upper limit; For the stress concentration area at the toe of the subgrade slope, the adsorption heat pipes are arranged in a denser pattern, and the transverse spacing is compressed to 0.8 ; Carry out collaborative optimization of the heat pipe subgrade, so that the coverage rate of the adsorption heat pipe, where is the projected area of the subgrade, and n is the number of heat pipes.

[0086] Among them, the length of the evaporation section of the heat pipe It is determined that when the refrigeration efficiency classification is Grade 1, the length of the evaporation section of the heat pipe , when the refrigeration efficiency classification is Grade 2, the length of the evaporation section of the heat pipe is within , when the refrigeration efficiency classification is Grade 3, the length of the evaporation section of the heat pipe ; the refrigeration efficiency classification is allocated according to the frozen soil thermal stability index , when the frozen soil thermal stability index , the refrigeration efficiency classification is Grade 1, when the frozen soil thermal stability index , the refrigeration efficiency classification is Grade 2, when the frozen soil thermal stability index , the refrigeration efficiency classification is Grade 3.

[0087] Its technical effects are as follows: calculating the spacing according to the effective refrigeration radius of a single heat pipe, making the refrigeration influence areas of adjacent heat pipes overlap by ≥ 30%, avoiding the occurrence of cold islands or blind areas, and ensuring the uniformity and continuity of the overall temperature field of the subgrade; for the weak parts with stress concentration such as the toe of the slope, compressing the lateral spacing to 0.8 Re, making the refrigeration density in the key area higher, so as to effectively suppress the risk of frozen soil deformation or settlement; automatically calculating the optimal installation inclination angle according to the thickness of the active layer of the frozen soil and the length of the evaporation section, so that the evaporation section can not only penetrate to the bottom of the active layer, but also maintain a buried depth margin of ≥ 1.5 m, ensuring that the ground temperature refrigeration effect is both deep and stable; through overall collaborative optimization, dynamically adjusting the number n of heat pipes to meet the set coverage rate requirements, while ensuring the heat control performance, avoiding the cost waste caused by excessive layout.

[0088] Among them, the parameters of the adsorption type all-season heat pipe that are corrected according to the heating prediction and dynamically adjusted for the refrigeration power model include: extracting the annual temperature increase rate in the next 50 years , updating the continuous cooling capacity against climate warming , where is the design life of the adsorption type heat pipe; updating the formula for the photothermal conversion efficiency of the adsorption type heat pipe , where is the current ambient temperature, represents the cumulative heating amplitude; updating the refrigeration power model of the adsorption type heat pipe ; updating the effective refrigeration radius , and adjusting the spacing between the adsorption type heat pipes according to the updated effective refrigeration radius .

[0089] Its technical effects are as follows: By introducing the current ambient temperature and the cumulative temperature rise term into the photothermal conversion efficiency formula, the calculation of the photothermal adsorption and refrigeration efficiency of the heat pipe can reflect the actual climate degradation situation, enhancing the timeliness and reliability of the model; Dynamically updating the refrigeration power model and the effective refrigeration radius, and adjusting the heat pipe spacing accordingly, to achieve an active maintenance strategy of "compensating the spacing with performance degradation and increasing or decreasing the number of pipes with the change of cooling capacity", avoiding the refrigeration blind area or efficiency attenuation caused by climate warming; Through multiple model corrections and layout fine-tuning during the design period, converting non-one-time excessive layout or frequent large-scale maintenance into data-based local adjustments, reducing the overall construction and operation and maintenance investment, and maximizing the long-term economic benefits.

[0090] Among them, for the prototype test of the heat pipe subgrade, data is collected in real time, and the measured ground temperature is compared with the designed target value. If the deviation exceeds the preset range, the parameters of the adsorption type all-season heat pipe are dynamically adjusted until the requirements for frozen soil thermal stability are met, including: Selecting an area with an annual average ground temperature of frozen soil as the test site, removing the surface vegetation to the frozen soil upper limit, and arranging according to the designed parameters of the adsorption type all-season heat pipe; Arranging optical fibers at a depth of 0-5m below the frozen soil upper limit, installing layered displacement gauges at the subgrade center line and slope toe, and installing pressure sensors and flow meters at the heat pipes at the same time; Conducting creep tests under multiple load levels, and recording the ground temperature data, deformation data and heat pipe parameters in real time; Calculating the ground temperature deviation , where is the ground temperature data recorded in real time, is the depth, is the time, is the number of temperature measurement points. If the ground temperature deviation lasts for 24 hours, it is determined that the deviation exceeds the preset range, and the regulation mechanism is triggered; After the regulation mechanism is triggered, adjust the refrigerant flow rate and the spacing between the adsorption type heat pipes until the requirements for frozen soil thermal stability are met.

[0091] Its technical effects are as follows: Conducting prototype tests under the on-site conditions where the annual average temperature of frozen soil ≥–0.5℃, comprehensively verifying the refrigeration effect and construction feasibility of the parameters such as the layout, depth and inclination angle of the heat pipes designed based on the model in the actual frozen soil environment; Using multi-dimensional monitoring means such as optical fiber ground temperature sensing, layered displacement gauges, pressure and flow sensors, and synchronously obtaining the ground temperature, deformation and heat pipe operation state data, providing reliable data support for evaluating the thermo-mechanical coupling response of frozen soil; Through continuously monitoring the ground temperature deviation formula for 24 hours, the deviation between the design target and the on-site measurement can be quickly identified, and potential thermal instability risks can be warned in advance, avoiding subgrade diseases caused by insufficient burial depth or uneven refrigeration; When the deviation exceeds the limit, the system can adjust the refrigerant flow rate and the local heat pipe spacing online, forming a closed loop of "monitoring → determination → regulation → verification", continuously optimizing the heat pipe system during operation, and ensuring that the thermal stability of permafrost continuously meets the standards.

[0092] The second embodiment of the present invention provides a permafrost railway subgrade structure design system based on an adsorption-type all-season heat rod, which includes: a remote sensing and ground temperature data acquisition module, which is used to evaluate the solar radiation intensity and the annual average ground temperature distribution of the frozen soil in the target area based on high-resolution remote sensing data and on-site ground temperature monitoring; a drilling module, which is used to determine the thickness of the frozen soil active layer, the spatial distribution of the frozen soil ice content and the thermal physical parameters of the frozen soil through geological drilling and geophysical exploration; a cooling power model construction module, which is used to establish a cooling power model of the adsorption heat rod according to the solar radiation intensity and the thermal physical parameters of the frozen soil. , calibrate the cooling efficiency of the adsorption-type heat rod; a heat rod parameter design module is used to design the layout parameters of the adsorption-type all-season heat rod in the roadbed according to the calibrated cooling efficiency of the adsorption-type heat rod; a heat rod parameter adjustment module is used to correct the cooling power model according to the temperature rise prediction, and dynamically adjust the parameters of the adsorption-type all-season heat rod; an experimental control module is used to conduct a heat rod roadbed prototype test, collect data in real time, and compare the measured ground temperature with the design target value. If the deviation exceeds the preset range, the parameters of the adsorption-type all-season heat rod are dynamically adjusted until the thermal stability requirements of the frozen soil are met.

[0093] The embodiment of the present invention aims to protect a method and system for designing a permafrost railway subgrade structure based on an adsorption-type all-season heat rod, and has the following effects:

[0094] (1) The present invention innovatively uses satellite remote sensing and ground monitoring data to obtain information such as roadbed temperature field, snow cover or vegetation cover, and integrates it into the model to improve the understanding of initial permafrost conditions and climate change;

[0095] (2) The present invention accurately calculates the heat demand of permafrost foundations, such as latent heat absorption and heat dissipation capacity of heat rods, based on energy balance, rather than simply taking empirical values, and can quantitatively analyze the cooling load under different climate scenarios;

[0096] (3) The present invention determines the spacing, depth and number of heat rods through simulation and optimization algorithms to maximize the cooling effect, such as adjusting the spacing of heat rods in combination with climate forecasts to avoid excessive heat overlap or missed areas;

[0097] (4) The present invention introduces an automated monitoring and adjustment mechanism during the operation of the heat rod, such as real-time temperature sensor feedback linkage control of the adsorbent temperature or additional refrigeration means and arrangement strategies, to perform closed-loop regulation of the refrigeration system, thus making up for the shortcomings of the traditional thermal control design of "post-construction inspection and re-evaluation" and achieving controllable and adjustable operation.

[0098] A computer program product of a design method and device for a permafrost railway subgrade structure based on an adsorption-type all-season heat pipe provided by an embodiment of the present invention includes a computer-readable storage medium storing program codes. The instructions included in the program codes can be used to execute the methods in the foregoing method embodiments. For specific implementation, reference can be made to the method embodiments, which will not be elaborated here.

[0099] Specifically, the storage medium can be a general storage medium, such as a mobile disk, a hard disk, etc. When the computer program on the storage medium is run, it can execute the above-mentioned design method for the permafrost railway subgrade structure based on the adsorption-type all-season heat pipe, thereby breaking through the limitation that the traditional siphon heat pipe only works in winter, ensuring that the subgrade maintains low-temperature heat dissipation ability throughout the year under different climate conditions, and greatly improving the thermal stability of the railway subgrade in the permafrost area.

[0100] If the above functions are implemented in the form of software function units and sold or used as independent products, they can be stored in a non-volatile computer-readable storage medium executable by a processor. Based on such an understanding, the essence of the technical solution of the present invention, or the part that contributes to the prior art, or a part of this technical solution, can be embodied in the form of a software product. The computer software product is stored in a storage medium and includes several instructions for causing a computer device (which can be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods described in various embodiments of the present invention. The foregoing storage medium includes: various media such as USB flash drives, mobile hard disks, read-only memories (ROM), random access memories (RAM), magnetic disks, or optical discs that can store program codes.

[0101] Finally, it should be noted that: the above-mentioned embodiments are only specific implementation manners of the present invention, used to illustrate the technical solutions of the present invention, rather than limiting them. The protection scope of the present invention is not limited thereto. Although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: any person skilled in the art within the technical scope disclosed by the present invention can still modify the technical solutions recorded in the foregoing embodiments or can easily think of changes, or perform equivalent replacements on some of the technical features; and these modifications, changes, or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present invention, and should all be covered within the protection scope of the present invention. Therefore, the protection scope of the present invention should be subject to the protection scope of the claims.

Claims

1. A design method for the permafrost railway subgrade structure based on an adsorption-type all-season heat rod, characterized in that, Including: Based on high-resolution remote sensing data and on-site ground temperature monitoring, evaluating the solar radiation intensity and the annual average ground temperature distribution of permafrost in the target area; Through geological drilling and geophysical prospecting, determining the thickness of the active layer of permafrost, the spatial distribution of ice content in permafrost, and the thermophysical parameters of permafrost; According to the solar radiation intensity and the thermophysical parameters of permafrost, establishing a refrigeration power model of an adsorption heat pipe and calibrating the refrigeration efficiency of the adsorption heat pipe; According to the calibrated refrigeration efficiency of the adsorption heat pipe, designing the layout parameters of the adsorption all-season heat pipe in the subgrade; According to the warming prediction, modifying the refrigeration power model and dynamically adjusting the parameters of the adsorption all-season heat pipe; Conducting a prototype test of the heat pipe subgrade, collecting data in real time, comparing the measured ground temperature with the designed target value, and if the deviation exceeds the preset range, dynamically regulating the parameters of the adsorption all-season heat pipe until the thermostability requirements of permafrost are met.

2. The design method of permafrost railway subgrade structure based on adsorption type all-season heat rods according to claim 1, characterized in that, The evaluating the solar radiation intensity and the annual average ground temperature distribution of permafrost based on high-resolution remote sensing data and on-site ground temperature monitoring includes: Obtaining a high-resolution multispectral remote sensing image of the target area and extracting the surface cover type and the spatial distribution data of surface temperature; Arranging on-site ground temperature observation boreholes, installing temperature measuring elements in the boreholes, conducting long-term continuous ground temperature monitoring at different depths and positions, recording the temperature changes in each season, and obtaining the seasonal ground temperature data of permafrost; Through remote sensing image interpretation technology, identifying the solar radiation absorption differences of different geomorphic units in the high-resolution multispectral remote sensing image, and establishing a solar radiation intensity distribution map, where the geomorphic units include at least one of shady slopes, sunny slopes, and vegetation-covered areas; Performing spatial interpolation on the spatial distribution data of the surface temperature and the seasonal ground temperature data of permafrost to generate a three-dimensional distribution model of the annual average ground temperature of permafrost; Overlaying the solar radiation intensity distribution map and the three-dimensional distribution model of the annual average ground temperature of permafrost to establish a radiation-ground temperature correlation matrix and dividing different thermostability regions.

3. The design method of a permafrost railway subgrade structure based on an adsorption-type all-season heat rod according to claim 2, wherein After establishing the radiation-ground temperature correlation matrix, it further includes: Substituting the measured data of the surface radiation flux into the solar radiation intensity distribution map to calibrate the model parameters.

4. The design method of the permafrost railway subgrade structure based on the adsorption type all-season heat rod according to claim 1, characterized in that, The determining the thickness of the active layer of permafrost, the spatial distribution of ice content in permafrost, and the thermophysical parameters of permafrost through geological drilling and geophysical prospecting includes: Using high-density electrical method and geological radar to conduct grid scanning on the target area and delineating the area with variable active layer thickness; Verification boreholes are arranged in the thickness change area of the active layer, and the borehole depth penetrates the permafrost to detect the thickness of the frozen soil active layer ; Extracting permafrost specimens from the boreholes and measuring the total water content by the volumetric method; Combining the borehole data with the empirical formula of resistivity ice content in geophysical prospecting to generate a three-dimensional model of the spatial distribution of ice content in permafrost; Using a thermal conductivity meter to calculate the thermal conductivity k of the permafrost specimen, measuring the specific heat capacity of the permafrost specimen and calculating the volumetric heat capacity C.

5. The design method of a permafrost railway subgrade structure based on an adsorption-type all-season heat rod according to claim 4, characterized in that The establishing a refrigeration power model of an adsorption heat pipe and calibrating the refrigeration efficiency of the adsorption heat pipe according to the solar radiation intensity and the thermophysical parameters of permafrost includes: According to the solar radiation intensity distribution map, extracting the total horizontal radiation amount S of the target area; Calculate the total cooling load according to the thermophysical parameters of frozen soil , where represents the cooling capacity required to reduce the frozen soil from the initial temperature to the target temperature , represents the continuous cooling capacity to resist climate warming is the soil mass within the refrigeration range is the heat transfer coefficient is the characteristic length is the Nusselt number is the temperature difference between the air temperature and the target ground is the annual refrigeration duration; Establish the formula for the photothermal conversion efficiency of an adsorption thermal rod , where is the nominal efficiency, is the temperature attenuation coefficient, is the temperature of the heat collection section, is the ambient temperature; Establish a refrigeration power model for an adsorption heat pipe , where is the effective area of the heat collection section, is the heat loss power, is the heat transfer coefficient of the pipeline, is the surface area of the evaporation section, is the ground temperature of the frozen soil; Calculating the annual cooling capacity of the heat pipe , based on the total cooling load and the calculation result of the annual cooling capacity of the heat pipe , calibrate the refrigeration efficiency of the adsorption heat pipe .

6. The design method of the permafrost railway subgrade structure based on the adsorption-type all-season heat rod according to claim 5, characterized in that Calibrate the refrigeration efficiency of the adsorption heat pipe After that, maintain the refrigeration efficiency to ensure redundant refrigeration capacity; If the refrigeration efficiency , then optimize and increase the heat collection area, reduce the heat loss, and adjust the refrigerant flow rate in sequence; The increased heat collection area includes expanding the effective area of the heat collection section and improving the nominal efficiency ; The heat loss reduction uses vacuum insulated pipes to reduce the heat transfer coefficient of the pipeline ; The refrigerant flow rate is adjusted by a valve to control the flow rate and lower the temperature of the heat collection section to below 7. The design method of the permafrost railway subgrade structure based on the adsorption type all-season heat rod according to claim 5, characterized in that The designing the layout parameters of the adsorption all-season heat pipe in the subgrade according to the calibrated refrigeration efficiency of the adsorption heat pipe includes: Calibration-based coefficient of performance of refrigeration , calculate the effective refrigeration radius of a single heat pipe , where is the annual refrigeration capacity of a single heat pipe, is the annual average ground temperature difference; According to the effective refrigeration radius , calculate the spacing between adjacent adsorption heat pipes, so that the longitudinal spacing , and the lateral spacing ; According to the thickness of the active layer of frozen soil , calculate the installation inclination angle of the adsorption heat pipe , where is the length of the evaporation section of the heat pipe, means that the evaporation section needs to penetrate the active layer and extend 1.5 m below the frozen soil upper limit; For the stress concentration area at the toe of the subgrade slope, the adsorption heat pipes are densely arranged, and the lateral spacing is compressed to 0.8 ; Carry out collaborative optimization of the thermosyphon subgrade to make the coverage rate of the adsorption thermosyphon , where is the subgrade projection area and n is the number of thermosyphons.

8. The design method of permafrost railway subgrade structure based on adsorption type all-season heat pipe according to claim 7, characterized in that The length of the evaporation section of the heat pipe Classified according to refrigeration efficiency It is determined that when the refrigeration efficiency classification is level one, the length of the evaporation section of the heat pipe , when the refrigeration efficiency classification is level two, the length of the evaporation section of the heat pipe is within , when the refrigeration efficiency classification is level three, the length of the evaporation section of the heat pipe ; The refrigeration efficiency classification is allocated according to the frozen soil thermal stability index When the frozen soil thermal stability index the refrigeration efficiency classification is Grade I. When the frozen soil thermal stability index the refrigeration efficiency classification is Grade II. When the frozen soil thermal stability index the refrigeration efficiency classification is Grade III.

9. The design method of the permafrost railway subgrade structure based on the adsorption-type all-season heat rod according to claim 7, characterized in that Based on the warming prediction, correcting the refrigeration power model, and dynamically adjusting the parameters of the adsorption type all-season heat pipe includes: Extract the annual temperature increase rate for the next 50 years , and update the continuous cooling capacity for resisting global warming , where is the design life of the adsorption heat pipe; Update the formula for the photothermal conversion efficiency of the adsorption heat pipe , where is the current ambient temperature, represents the cumulative temperature rise amplitude; Update the refrigeration power model of the adsorption heat pipe ; Update the effective cooling radius , and adjust the spacing between the adsorption heat pipes according to the updated effective cooling radius .

10. The design method of permafrost railway subgrade structure based on adsorption full-season heat rods according to claim 7, characterized in that, Conducting a prototype test of the heat pipe subgrade, collecting data in real time, comparing the measured ground temperature with the designed target value. If the deviation exceeds the preset range, dynamically adjusting the parameters of the adsorption type all-season heat pipe until the permafrost thermal stability requirements are met, including: Select the area with the average annual ground temperature of frozen soil as the test site, remove the surface vegetation to the frozen soil upper limit, and arrange according to the designed parameters of the adsorption type all-season heat pipe; Laying optical fibers at a depth of 0-5 m below the permafrost table, installing layered displacement gauges at the center line and toe of the subgrade, and installing pressure sensors and flow meters at the heat pipes simultaneously; Conducting creep tests under multiple load levels, and recording ground temperature data, deformation data and heat pipe parameters in real time; Calculate the ground temperature deviation , where is the ground temperature data recorded in real time, is the depth, is the time, is the number of temperature measurement points. If the ground temperature deviation lasts for 24 hours, it is determined that the deviation exceeds the preset range and the regulation mechanism is triggered; After triggering the regulation mechanism, execute adjusting the refrigerant flow rate and adjusting the spacing between the adsorption type heat pipes until the permafrost thermal stability requirements are met.

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