499 results about "Gelisol" patented technology

The invention discloses a multi-sensing and data physical fusion frozen soil hot water force response test system and method, and the system integrates an ultra-weak fiber grating, an active heating fiber, a miniature dielectric constant sensor and an optical frequency domain reflection technology, and constructs a freezing process-oriented temperature, moisture, ice content and strain synchronous monitoring network; the method comprises the steps of constructing a multi-field fusion data set based on thermal disturbance lag correction, temperature-strain decoupling and a moisture-strain residual term compensation mechanism, and extracting key criterion characteristics of an ice lens growth rate, frost heaving force evolution and a shear deformation change rate; and in combination with a physical information neural network (PINN) embedded into a hot water force control equation, risk identification and grade judgment of the freezing abnormal behavior are realized. The method supports indoor heating and water pressure linkage adjustment, realizes a complete closed loop of multi-source sensing-risk identification-response verification under model driving, and breaks through the bottlenecks of low multi-physics field coupling identification precision, large parameter cross interference and insufficient risk identification real-time performance of the existing monitoring technology.

The invention relates to the technical field of model construction, and discloses a neural network-based frozen soil unfrozen water content detection model construction method and system. The method comprises the following steps: carrying out segmented sampling test on a clay sample in a temperature interval of 0 DEG C to-20 DEG C to obtain a multi-dimensional original data set, and carrying out standardization and principal component analysis on the data set to obtain a standardized feature vector; and performing three-stage classification marking on the feature vectors to obtain a training data matrix. A deep neural network is adopted to carry out five-fold cross validation training, and a prediction model of three hidden layers is constructed. And performing correction calculation on model output according to soil mineral composition and porosity parameters, and finally identifying an abnormal value through root-mean-square error analysis and a three-time standard deviation principle to obtain a standardized prediction result. According to the method, the mapping relation between the thermal parameters and the unfrozen water content is established, correction is carried out in combination with the soil body characteristic parameters, and the technical problem that the prediction precision of the unfrozen water content is not high in the prior art can be solved.

The invention discloses a roadbed settlement prediction method based on IGWO-BP and ARIMA. The roadbed settlement prediction method comprises the following steps: firstly, obtaining a seasonal permafrost region settlement data composition, wherein the seasonal permafrost region settlement data composition comprises short-term linear characteristics and long-term nonlinear change characteristics; preprocessing the original monitoring data, dividing the data into a training set and a test set, and constructing an IGWO-BP model based on the training set; then, an IGWO-BP model is trained on the training set, a training residual sequence is further obtained, and meanwhile, the trained IGWO-BP model is adopted to predict the test set; constructing a model ARIMA, and predicting a network residual error based on the model; finally, the prediction result of the IGWO-BP model and the residual error sequence prediction result of the ARIMA model are connected in series, error correction of the prediction result is completed, and a final combined prediction result is obtained.By means of the method, the freezing injury occurrence characteristics of the seasonal frozen soil region can be well captured, and the defect of prediction of a single model is overcome.

The invention provides a seasonal frozen earth region roadbed stability evaluation method, a seasonal frozen earth region roadbed stability evaluation device and a medium, and relates to the technical field of seasonal frozen earth region roadbed stability evaluation. Meanwhile, performing a freeze-thaw cycle experiment in a laboratory, and fitting to obtain a heat conduction coefficient and a moisture diffusion coefficient of the soil sample; inputting field data and experimental parameters into the finite element model, simulating hydrothermal transfer and mechanical behaviors under different seepage and drainage grating arrangement conditions, and analyzing dynamic change rules of a temperature field, a water content field and frost heaving stress; then, a hydrothermal dynamic behavior and rib-soil interface behavior prediction model is trained based on an LSTM network architecture, and hydrothermal changes and mechanical properties of the roadbed under different conditions are predicted; and finally, based on an output result of the prediction model, calculating a roadbed stability index by combining a comprehensive stability evaluation model.

The invention discloses an intelligent heating geogrid-based roadbed settlement and frozen soil plasticity prediction system, which comprises an intelligent heating geogrid, a data acquisition unit, an intelligent heating control unit, a moisture content calculation unit and an analysis prediction unit, the intelligent heating control unit performs starting control on the heating resistance wire according to a soil body temperature value collected by the optical fiber temperature sensor so as to heat the self-heating steel pipe, the self-heating steel pipe heats the soil body, and the moisture content calculation unit calculates the moisture content of the soil body according to a temperature rise value of the soil body in unit time. And the analysis and prediction unit predicts roadbed settlement and frozen soil plasticity according to the soil moisture content and the grating dependent variable. The self-heating steel pipe is installed on the grating body, the water content of the soil body is monitored in real time while the soil body is heated, the subgrade settlement state and the frozen soil plastic characteristics are accurately predicted according to the collected data, and therefore scientific support is provided for safety evaluation and maintenance of subgrade engineering.

The invention discloses a multi-target intelligent optimization method and system for blasting parameters of a strip mine in a high-altitude cold region. The method comprises the following steps: carrying out data acquisition to obtain a parameter data set; performing data preprocessing on the parameter data set to obtain a feature sample set; constructing an initial blasting parameter model based on a machine learning algorithm, and performing hyper-parameter optimization on the model to obtain a blasting parameter model; a multi-objective optimization function is constructed: based on the multi-objective optimization function and the blasting parameter model, solving is carried out in combination with environmental condition constraints, and a pareto optimal solution set is obtained; according to the pareto optimal solution set, a representative solution is selected, a visual scheme is generated, and blasting parameter optimization of the strip mine in the high-altitude cold region is completed. According to the method, temperature, oxygen and frozen soil constraint conditions of the high-cold and high-altitude environment are introduced, blasting safety, lumpiness uniformity and the explosive utilization rate are considered at the same time through multi-target collaborative optimization, the method can adapt to the extreme environment, meanwhile, the one-sidedness of single-target optimization is avoided, and the intelligent level of blasting design and implementation is greatly improved.

The invention discloses a multi-stage layered frozen soil sampling device, and particularly relates to the technical field of soil sampling, the multi-stage layered frozen soil sampling device comprises a mounting disc, a plurality of sealing plates on the surfaces of a plurality of sampling covers can be opened under the action of centrifugal force, and then scrapers in two sealing plates can scrape soil and make the soil enter the sampling covers, so that the soil can be sampled; then, a rubber sealing cover extruded by the soil moves downwards to drive a sleeve to enable a plurality of first connecting columns to extrude a plurality of third springs, meanwhile, the sleeve moves downwards to drive two steel wire ropes to pull two sealing plates, and at the moment, under the resilience force action of the two steel wire ropes and reset springs, the two sealing plates can reset to the initial positions; the sampling covers are arranged on the upper portion of the soil sampling device, the sampling covers on the upper portion can repeat the steps to collect the soil, the phenomenon of soil layer channeling in the soil sampling process can be prevented, and meanwhile due to the fact that the multiple sampling covers are independent individuals, the multi-stage stratified sampling effect can be achieved in the sampling process.

The invention discloses an anti-freezing power transmission line tower supporting foundation suitable for a frozen soil area, relates to the technical field of power transmission line tower supporting, and aims to solve the problem that an existing power transmission line tower supporting foundation cannot resist freezing and cannot keep supporting efficiency under season replacement. Comprising a pile foundation cylinder, a pile foundation cylinder inner supporting column, an arc-shaped heat conduction pipe and a frost heaving piercing mechanism. A pile foundation cylinder top seat and a power transmission line tower connecting frame are mounted at the top of the pile foundation cylinder; the pile foundation cylinder inner supporting column is embedded in the pile foundation cylinder, circulating flow channels are designed between the pile foundation cylinder inner supporting column and the pile foundation cylinder and between the pile foundation cylinder inner supporting column and the arc-shaped heat conduction pipe, and an equipment mounting inner cavity is formed in the top of the pile foundation cylinder inner supporting column. When the soil body is subjected to frost heaving, the transverse anchor rods can pierce into the surrounding soil body, so that the pile foundation cylinder and the surrounding soil body are anchored together, and the frost heaving is further resisted.

The invention discloses a method and a device for testing moisture migration characteristics of frozen soil under low-temperature nuclear magnetic triaxial seepage, and relates to the technical field of frozen soil testing. In order to solve the problems that in the prior art, compatibility control of freezing and seepage cannot be achieved, and whole-process evolution of frozen soil moisture migration characteristics is difficult to dynamically capture, the scheme comprises the following steps that the real confining pressure, axial pressure and seepage speed of the environment where a soil sample is located are simulated; collecting a nuclear magnetic resonance image and an overall and layered T2 spectrum of the soil sample before freezing under the action of seepage; gradually freezing the soil sample based on different temperature gradients, and collecting a nuclear magnetic resonance image and an overall and layered T2 spectrum of the soil sample under the seepage and freezing coupling action in real time; data are collected according to the whole soil sample freezing process, and the evolution law of water migration characteristics in the soil body freezing process is analyzed. According to the invention, the whole-process, visual and nondestructive detection is realized, and the whole-process evolution rule of water migration characteristics such as unfrozen water content and pore cracks in the frozen soil under the seepage and freezing coupling action can be accurately captured.

The invention discloses a cold region hydrological process simulation method based on a dynamic soil water storage capacity parameter. A static soil water storage capacity parameter Smax in an RCC-WBM model is replaced with a dynamic soil water storage capacity parameter DSmaxi related to temperature. The cold region hydrological process simulation method based on the dynamic soil water storage capacity parameters is provided on the basis of an RCCC-WBM model and a physical mechanism that air temperature changes affect the cold region soil water storage capacity parameters, and the cold region runoff process under frozen soil changes can be simulated more objectively and accurately; by utilizing the method, the change of the soil water storage capacity under the frozen soil change can be quantified, and the environmental influence evaluation work of climate change is effectively supported; by means of the method, the runoff trend of the cold region can be well simulated, and drainage basin water resource evaluation and planning management work is effectively supported.

The invention relates to the technical field of remote sensing science and technology, in particular to a frozen soil region freeze-thaw disaster identification method and system and a storage medium, and the method comprises the steps: generating a target differential interference image set; carrying out homogeneous point filtering, phase unwrapping optimization and unwrapping error correction on the basis of the target differential interference image set to obtain an unwrapped phase image set; for each unwrapped phase diagram, performing uniform sub-block division, and based on an elevation-phase empirical relationship, estimating and removing an atmospheric delay phase existing in each sub-block through a linear fitting method to obtain a phase optimization diagram set after atmospheric influence is removed; performing sequential superposition on unwrapping phases corresponding to the interferograms in the phase optimization diagram set, and performing analysis by using the relationship between the average phase change rate after superposition and the radar wavelength to obtain earth surface deformation data; and unsupervised classification and screening are carried out based on the earth surface deformation data, and freeze-thaw change areas are optimized, so that a high-precision freeze-thaw recognition result is obtained.

The invention discloses a remote sensing image-based western plateau frozen soil hot melt disaster identification method. The method comprises the following steps of obtaining and preprocessing a satellite remote sensing image and a radar remote sensing image of a western plateau frozen soil preset area; performing multi-scale segmentation on the preprocessed satellite remote sensing image to obtain frozen soil characteristics of a preset area; performing time sequence InSA analysis on the preprocessed radar remote sensing image to obtain the earth surface deformation rate of the preset area; constructing a western plateau frozen soil hot melt disaster identification model based on the frozen soil characteristics and the earth surface deformation rate; and based on the western plateau frozen soil hot melt disaster identification model, completing western plateau frozen soil hot melt disaster identification based on the remote sensing image. According to the invention, the occurrence and evolution trend of frozen soil hot melt disasters can be found in time. By constructing a disaster recognition model, early warning and monitoring of potential disaster areas can be realized, and a scientific basis is provided for disaster prevention and control.

The invention discloses an island-shaped frozen soil degradation prediction method based on remote sensing and ground temperature coupling, and relates to the technical field of frozen soil degradation prediction in cold regions, and the method comprises the following steps: S1, multi-source data fusion and intelligent decomposition, S2, cross-scale dynamic parameterized model construction, S3, quantum enhanced Bayesian multi-scale calibration, and S4, three-dimensional dynamic uncertainty quantification and prediction output. According to the method, the problems of frozen soil data scarcity and remote sensing conversion precision are solved through multi-source remote sensing and actually measured data fusion in combination with CGAN, AM-PFN and virtual sample closed-loop expansion; the defects of a traditional model are overcome through a microscopic-macroscopic coupling model, DRL parameter switching and meta-learning algorithm selection; through quantum enhanced Bayes, DMD and a four-dimensional uncertainty matrix, cross-scale prediction divergence is reduced; and through a carbon release risk correlation model and a co-evolution product, a prediction dimension is expanded, and a support is provided for ecological protection of the cold region.

The invention provides a nuclear magnetic resonance and image intelligent bimodal unfrozen water dynamic identification method and system, and belongs to the technical field of frozen soil engineering and geophysical exploration, and the method comprises the steps: sealing a frozen soil sample in a nuclear magnetic sample tube, and achieving the gradient cooling of the sample in a preset low temperature range through temperature control; scanning by using a nuclear magnetic resonance technology to obtain transverse relaxation time T2 spectrums and nuclear magnetic images of the frozen soil sample at different temperature nodes; after image preprocessing is carried out on the nuclear magnetic image, a temperature-signal intensity curve in the nuclear magnetic image is automatically extracted by utilizing an image recognition technology; carrying out integral calculation on a liquid water signal in the T2 spectrum, and dynamically calculating the content of the unfrozen water at each temperature based on a nuclear magnetic signal intensity formula; according to the method, a pore-fracture co-evolution matrix is constructed, accurate analysis of unfrozen water dynamic and pore evolution in the freezing and thawing process is realized, the method is suitable for hydrothermal coupling characteristic analysis of Qinghai-Tibet soil in a complex freezing and thawing environment, and reliable technical support is provided for stability evaluation of frozen soil engineering.

The invention discloses a permafrost hydrothermal state simulation method and system based on a physical model, and relates to the technical field of permafrost region engineering. The method comprises the following steps: acquiring meteorological driving data and land surface feature data; constructing a numerical model of a permafrost hydrothermal process by considering a permafrost freezing and thawing process and a soil ice effect by utilizing land surface feature data; preparing boundary constraint conditions of the numerical model according to the meteorological driving data and the existing temperature field data; and performing permafrost hydrothermal state simulation on the land surface characteristic data by using meteorological driving data, constraint condition data, key vegetation and soil parameters and a driving numerical model to obtain a sample set formed by key permafrost hydrothermal information. According to the method, the dependence of an existing model on data and structures is broken through, the multi-scale application requirement of the permafrost region is met, and finally a high-quality meteorological driving and boundary constraint condition data set suitable for permafrost simulation without an observation region can be generated.

The invention provides a method and system for simultaneously measuring frozen soil pore ice content and unfrozen water content, and belongs to the technical field of frozen soil parameter measurement based on machine learning, and the method comprises the following steps: acquiring a temperature response curve and specific frozen soil parameters of frozen soil under a pulse heat source; the specific frozen soil parameters comprise frozen soil particle density, frozen soil particle heat conductivity coefficient, frozen soil particle specific heat capacity and frozen soil particle specific gravity; and processing the obtained temperature response curve and the specific frozen soil parameters by using a pre-trained inversion analysis model to obtain the frozen soil ice content and the unfrozen water content. The ice content and the unfrozen water content of the frozen soil can be measured at the same time within one minute, the measurement efficiency is greatly improved, and assumed conditions of an empirical model are avoided at the same time.

The invention relates to the technical field of tunnel engineering construction, in particular to a high and cold tunnel variable cross-section frozen soil thermal coupling safety hierarchical control construction method, which comprises the following steps: constructing a three-dimensional thermal coupling model considering frozen soil phase change characteristics based on an FLAC3d platform, and introducing a freezing frontal surface expansion speed prediction algorithm and ground temperature monitoring data to dynamically correct model parameters; a three-level safety threshold is established, a hierarchical control strategy is implemented, a pre-control period (heating and heat preservation), an excavation period (advanced small pilot tunnel and reverse top-picking expanding excavation) and a support period (asymmetric support) are divided, and a closed-loop system for monitoring, simulation, feedback and adjustment is established. The method comprises the following steps of: accurately regulating and controlling a temperature field, setting a phase change energy storage heat preservation layer, constructing a bionic drainage system, applying an intelligent construction platform with BIM (Building Information Modeling) and GIS (Geographic Information System) fused, integrating various sensing equipment for real-time monitoring, comparing monitoring data with a model prediction result, dynamically optimizing construction parameters and ensuring construction safety.

The invention relates to the technical field of frozen soil collection, and discloses a plateau frozen soil sample collection device which comprises a mounting table, a sampling outer cylinder is arranged below the mounting table, a heating cavity is formed in the sampling outer cylinder, and electric heating rods are fixedly mounted on the two sides of the top of the sampling outer cylinder; and the heating end of the electric heating rod extends into the heating cavity. When frozen soil is collected and sampled through rotation of the sampling outer cylinder and the sampling inner cylinder, an anti-freezing solution in the heating cavity can be heated through the electric heating rod, and heat is dissipated to the outside through the sampling outer cylinder, so that ice crystals in the frozen soil outside the sampling outer cylinder are melted, and the sampling cylinder can quickly penetrate through a frozen soil layer; and meanwhile, the anti-freezing solution in the water storage tank is circularly pumped into the cooling cavity in the sampling inner barrel to cool the sampling inner barrel, so that the situation that heat is generated due to friction between the sampling inner barrel and the sampled frozen soil is reduced, the original state of the frozen soil sample can be kept, and the sampling accuracy is ensured.

The invention relates to the related technical field of climate monitoring, in particular to a freezing circle climate change monitoring method and system suitable for an Asian alpine region, and the method comprises the steps: configuring a monitoring network, receiving a frozen soil multi-source monitoring data set, constructing a frozen soil and climate coupling response model, embedding a region climate assessment engine, and generating a frozen soil degradation risk grade distribution map. And judging whether risk reminding is triggered or not according to the dynamic frozen soil degradation threshold value, and if the risk reminding is triggered, marking an abnormal region in the frozen soil degradation risk level distribution diagram. The technical problems that Asian alpine region freezing circle climate change monitoring abnormity reminding mostly depends on static data, the dynamic evolution process of frozen soil cannot be accurately captured, and the frozen soil degradation risk identification precision is limited are solved, a frozen soil and climate coupling response model constructed based on multi-source data is achieved, and the frozen soil degradation risk identification accuracy is improved in combination with a dynamic degradation threshold value set according to the frozen soil type. And risk reminding is triggered in time and an abnormal region is marked, so that the frozen soil degradation risk identification precision is improved.

The invention relates to a permafrost region pile periphery soil re-freezing construction method which comprises the steps that a plurality of cooling pipes are erected along with a reinforcement cage of a pile foundation in advance, the liquid inlet ends of the cooling pipes are connected with a natural cooling tank through a liquid pump and a refrigerant inflow pipeline, and refrigerants are arranged in the natural cooling tank; the liquid outlet end of the cooling pipe is connected with a natural cooling tank through a refrigerant outflow pipeline to form a refrigerant circulating system; the pile foundation is poured, the multiple cooling pipes are embedded into the pile foundation, in the pile foundation pouring and maintaining process, a liquid pump is started, a refrigerant flows, and the pile foundation and frozen soil on the pile side are cooled through the cooling pipes; after the pile foundation is built, the cooling pipe is separated from the cooling circulation system, the refrigerant in the cooling pipe is pumped out, then evaporated liquor is added into the cooling pipe, and the condensation sections of the hot rods are installed at the liquid outlet end and the liquid inlet end of the cooling pipe, and by the adoption of the method, quick re-freezing of the frozen soil around the pile is achieved, and the construction progress is accelerated.

The invention relates to the technical field of soil porosity detection, in particular to a frozen soil parameter detection device which comprises a detection box, a shooting analysis module and a pair of box doors hinged to the front side of the detection box, a round rod is rotatably connected to the inner side of the detection box, and an upper disc is fixedly connected to the outer wall of the round rod. Through the arrangement of the structure, the temperature of a frozen soil sample sampling position is simulated in cooperation with a high and low temperature controller in the box, so that frozen soil samples in the multiple cutting rings can be ejected out and scraped off in a running water mode, the working efficiency is improved, the working efficiency is improved, and the working efficiency is improved. According to the device, the porosity of multiple frozen soil samples can be detected at the same time, the detected cutting ring can be automatically pushed out, the cutting ring with the soil sample to be detected can be pushed into the circular cavity for detection, synchronous detection of the multiple samples can be achieved at the same time, the number of times of opening a door for lofting testing by detection personnel is reduced, and the detection efficiency and accuracy of the device are further improved.

The invention discloses a saline-alkali frozen soil multi-field synchronous monitoring device and method based on a weak reflection grating. The device comprises a temperature, humidity, salt and ice sensing module, a strain sensing module, an interlocking connector, a weak reflection grating demodulation module, a voltage stabilization direct current heating module and a data analysis and processing module. During monitoring, the temperature of the saline-alkali frozen soil is measured in the whole time period based on pulse temperature change and water-ice phase change through weak reflection grating sensing; the humidity and the ice content of the saline-alkali frozen soil are calculated through the pulse heating temperature time history curve; calculating the salt content of the saline-alkali frozen soil based on the wavelength reflectivity; calculating layered displacement of the saline-alkali frozen soil according to the relationship between strain and displacement; and correcting a multi-field monitoring data error by using a neural network. According to the invention, synchronous measurement of temperature, moisture content, salt content, ice content and deformation parameters of the saline-alkali frozen soil is realized, the problem of difficulty in synchronous measurement of multi-field parameters caused by unstable properties of the saline-alkali frozen soil is solved, and the system has the advantages of distribution, real-time performance and continuity.

The invention discloses a method for comparing and selecting road base programs in seasonal frozen soil areas, comprising the following steps: step 1: analyzing the special geographical environment of seasonal frozen soil areas, clarifying the evaluation object system of the program, and listing the influencing factors of the research object; step 2: analyzing the manifestation of the influencing factors at all levels, describing the influence mechanism of the manifestation of the influencing factors on the research object, determining the evaluation index system, and constructing a pre-analysis framework for comprehensive evaluation; step 3: based on a data evaluation model, unifying the original observation point data of the evaluation index, obtaining a forward matrix and performing normalization processing to eliminate the influence of the dimensions of the indicators at all levels, and determining the analysis data matrix; step 4: calculating the distance between each evaluation object and the optimal program and the worst program, and using this as the basis for evaluating the pros and cons; step 5: sorting the distance between the evaluation object and the optimal solution and the worst solution, judging the relative closeness of each evaluation object to the optimal program, and realizing the optimal comparison and selection of the program.

The invention discloses a frozen soil active layer thickness inversion method, medium and equipment, and relates to the field of radar remote sensing image processing, and the frozen soil active layer thickness inversion method mainly comprises the steps: obtaining deformation information according to single-view complex orbit descending data, digital elevation model data and atmospheric delay data; according to the deformation information, obtaining to-be-selected long-term deformation and to-be-selected seasonal deformation of the permafrost by using multiple decomposition algorithms; evaluating the to-be-selected long-term deformation and the to-be-selected seasonal deformation, and determining long-term deformation and seasonal deformation; and obtaining the thickness of the active layer of the research area according to the seasonal deformation and the layered soil water content data. By implementing the frozen soil active layer thickness inversion method, the medium and the equipment provided by the invention, the accuracy of frozen soil active layer thickness inversion can be improved.

The invention discloses a frozen soil thermal characteristic measuring device and method based on a thermal pulse method, and the method comprises the steps: heating a cylindrical heating probe through a heater at a constant power, detecting the temperature of the cylindrical heating probe through a first temperature probe, and uploading the temperature to a cloud through a transmission unit; meanwhile, the data recorder displays the temperature data of the second temperature probe and the first temperature probe in real time; keeping the temperature of the cylindrical heating probe constant; a frozen soil sample is heated by the cylindrical heating probe, a temperature penetration curve of the frozen soil sample is obtained, and then the volume diffusivity and the volume thermal conductivity of the frozen soil sample are obtained. According to the method, the highest space temperature can be effectively kept below the freezing point, so that the overall thermal performance of the quartz sand and the ice content is estimated, and the accuracy of estimating the overall thermal performance of the frozen soil sample in the cold region is improved.

The invention provides a soil permeability test device suitable for gradient variable-temperature freeze-thaw cycle test, which comprises a temperature control cylinder formed by axially extending and combining a plurality of annular insulating cylinders with hollow structures, an insulating and heat-conducting soil sample cylinder is mounted in a central chamber formed by the temperature control cylinder, a water storage chamber is arranged on one side of the soil sample cylinder, and a water outlet is formed in the other side of the soil sample cylinder. A porous anode plate is arranged between the water storage chamber and the soil sample cylinder, a water collecting chamber is arranged on the other side of the soil sample cylinder, a porous cathode plate is arranged between the water collecting chamber and the soil sample cylinder, an orifice plate flowmeter is arranged between the water collecting chamber and the porous cathode plate, and the water storage chamber is connected with a water supply system; a pore pressure sensor and a temperature sensor are installed on the side wall of each annular insulating cylinder, and each annular insulating cylinder is connected with a refrigeration module and a heating module. The device can simulate a real environment to perform freezing and thawing and gradient temperature control on the sample, can effectively simulate a real geological environment in an alpine region, and provides a scientific basis for research on permeability of frozen soil under a gradient freezing and thawing cycle condition.

The invention discloses a roadbed settlement prediction method and system for a permafrost region. The roadbed settlement prediction method comprises the steps of obtaining roadbed historical data corresponding to the permafrost region; intercepting data of a preset fixed length and settlement monitoring data corresponding to the data of the preset fixed length at a future moment, and constructing a permafrost region roadbed settlement sample database; building a base model; training the base model through the established database to obtain a trained base model; outputting a preliminary prediction result through the trained base model; the prediction result of the base model is used as the input of a meta-model through a stacking model, the meta-model is a multiple linear regression model, the prediction results of multiple prediction units of the base model are integrated, and the roadbed settlement corresponding to the final permafrost region future moment is output. According to the method, prediction results of a plurality of models are fused, so that the final model is more robust for abnormal values and noise data, and the stability of training prediction of the model for large fluctuation of roadbed settlement data in the frozen soil region is improved.

The invention relates to a device and method for testing the heat conductivity coefficient of frozen soil in a near-phase-change region, and the device is characterized in that a heat-TDR probe sensor is inserted into a to-be-tested soil sample, then is sealed, and is placed into a constant-temperature liquid bath; the thermal-TDR probe sensor is used for performing integrated heating on a to-be-measured soil sample, measuring the temperature of the to-be-measured soil sample and measuring the dielectric constant of the to-be-measured soil sample, a lead of the thermal-TDR probe sensor is connected to the temperature acquisition device and the TDR-100 signal acquisition device, the TDR-100 signal acquisition device is connected to the TDR signal receiving device, and the TDR signal receiving device is connected to the thermal-TDR probe sensor. And the temperature acquisition device and the TDR signal receiving device transmit acquired signals to the processor. The phase change latent heat influence is considered, the water-ice phase change latent heat error correction method under the pulsating heat flow effect is defined, the calculation formula of the frozen soil heat conductivity coefficient of the near-phase-change area is corrected, and the test error of the frozen soil heat conductivity coefficient is reduced; and a guarantee is provided for accurately revealing the change rule of the frozen soil heat conductivity coefficient in the continuous temperature change process of the near-phase-change region.

The invention discloses a frozen soil column test device and method based on thermoelectric refrigeration and DIC monitoring, the device comprises a transparent soil column container, a temperature control system and a digital image acquisition system, the transparent soil column container is used for containing a soil column sample, and the transparent soil column container is formed by combining two double-layer cylinder wall acrylic semicircular cylinders; the frozen soil freezing process and the frost heaving behavior are visualized, and real-time monitoring and analysis are facilitated. During an experiment, internal and external temperatures are accurately adjusted through a temperature control system to simulate a frozen soil freezing process; the digital image acquisition system shoots a soil column surface image in real time through a high-resolution camera, digital speckles are combined, real-time monitoring and analysis of the soil body frost heaving amount and the freezing frontal surface position are carried out through a digital image related technology, and the soil body frost heaving characteristic and the freezing frontal surface dynamic change can be measured with high precision.

The invention discloses a method for analyzing an action mechanism of a frozen soil active layer on decomposition of falling leaves of dahurian larch. The method specifically comprises the following steps: S1, analyzing the influence of the frozen soil active layer on forest stand and soil characteristics of the dahurian larch; s2, analyzing the response of the leaf characters of the dahurian larch and the phyllospheric microflora characteristics of the dahurian larch to a frozen soil active layer; s3, analyzing an action mechanism of a frozen soil active layer on decomposition of fallen leaves of the dahurian larch forest; according to the method, forest stand characteristics, soil physicochemical properties, leaf traits, phyllospheric microorganism characteristics, litter leaf traits and decomposition rates of the dahurian larch under frozen soil active layers with different thicknesses are investigated. The invention aims to analyze the structural characteristics of microflora at the phyllosphere of the dahurian larch under frozen soil active layers with different thicknesses, reveal a response strategy adopted by the leaf characters of the dahurian larch to adapt to environmental changes, explore the decomposition difference and main influence factors of the litter leaves, and clarify the action mechanism of the frozen soil active layers on the decomposition of the litter leaves.