235 results about "Permeability coefficient" patented technology

The invention discloses a viscous coarse-grained soil permeability coefficient prediction method based on a physical constraint neural network, and the method comprises the following steps: carrying out an indoor viscous coarse-grained soil seepage test, and establishing a viscous coarse-grained soil permeability coefficient formula considering porosity and grain composition characteristics, further constructing a mixed model containing a physical driving item and a neural network data driving item, forming a complete data set through a numerical simulation technology and literature investigation on the basis of a seepage test, complementarily collecting porosity, grain composition characteristics and corresponding permeability coefficient data of the viscous coarse-grained soil sample, and dividing the complete data set into a training set and a test set; according to the method, optimal hyper-parameters are dynamically searched in combination with Bayesian optimization for model training, a loss function curve and permeability coefficients of the viscous coarse-grained soil under different porosity and grading characteristics are obtained, tests show that high-precision prediction of the permeability coefficients of the viscous coarse-grained soil is achieved, and the problems that a traditional method is insufficient in physical constraint and low in prediction precision are solved.

The invention relates to the technical field of geotechnical engineering construction, in particular to a valley accumulation body curtain grouting construction control method based on SVM and PID, which comprises the following steps: obtaining construction data including stratum permeability coefficient, grouting pressure, slurry consistency, grouting flow and slurry diffusion range; constructing a three-dimensional geologic model of the canyon accumulation body, associating the parameters with corresponding positions in the model, generating a construction feature vector with geological attributes, inputting the construction feature vector into a pre-trained SVM model so as to predict a geological response trend, correcting control parameters of a PID control model according to the geological response trend, and then dynamically regulating and controlling operation parameters of grouting equipment, so as to achieve the purpose of predicting the geological response trend. PID control parameters and grouting key parameters are continuously optimized. Therefore, the problems that in the prior art, self-adaptive control over complex and changeable geological conditions is difficult to achieve, grouting parameter setting is not accurate, and construction quality is not stable are solved.

The invention discloses an expansive soil free expansion rate and permeability coefficient field test device and method, relates to the technical field of expansive soil tests, and aims to solve the problems that in the prior art, expansive soil expansion potential judgment standards are not unified, and test data discreteness is large. Comprising a cutting ring assembly, a moisture content measuring assembly, a displacement measuring assembly and a water supply assembly. The cutting ring assembly is used for fixing a test soil body; the moisture content measuring assembly monitors the moisture content of the soil body in real time; the displacement measuring assembly records soil surface and deep displacement; the water supply assembly controls water injection. The test method comprises a test method and a numerical analysis method, the permeability coefficient and the free expansion rate of the soil body are calculated by injecting water and monitoring the moisture content and the displacement change of the test soil body, a moisture content curve is fitted by combining numerical analysis, the expansion coefficient and the saturated moisture content are solved, and the free expansion rate of the soil body is finally determined. The free expansion rate and the permeability coefficient of the expansive soil are rapidly and accurately measured on site, the expansion potential is judged, and a reliable basis is provided for engineering application.

The invention belongs to the technical field of hydraulic structure engineering, and relates to a dam foundation curtain anti-seepage performance evaluation method and system under the action of seepage corrosion, and the method comprises the steps: drawing a hydropower station dam engineering riverbed cross section geometric model, and carrying out the mesh generation of the geometric model to obtain a calculation model; constructing a dam foundation anti-seepage curtain corrosion degradation analysis initial model; coupling a seepage field, a calcium ion transport field and a corrosion field in the dam foundation anti-seepage curtain corrosion degradation analysis initial model by utilizing the calculation model to obtain a permeability coefficient, porosity and a diffusion coefficient; updating parameters to obtain a dam foundation anti-seepage curtain corrosion degradation analysis updating model; whether the permeability coefficient, the porosity and the diffusion coefficient converge or not is judged, and if yes, the anti-seepage curtain structure calcium ion concentration, the solid-phase calcium concentration and the water head corresponding to the parameters are output; evaluating the anti-seepage performance of the dam foundation curtain; and otherwise, carrying out coupling solution on the analysis updating model by utilizing a calculation model. The technical problem of inaccurate calculation results in the prior art is solved.

The invention provides a numerical simulation method and system based on rock mass fracture extension and seepage coupling, and belongs to the field of rock mechanics. Rock is regarded as a set composed of particles and mechanical contact between the particles, and a triangulation network is constructed based on the circle center of each particle; according to the geometrical characteristics of the triangulation network, a seepage pipeline network containing the interior and the periphery is built, and network nodes and boundary nodes are determined; calculating the permeability coefficient according to the particle positions on the two sides of the pipeline, and forming a penetrating seepage channel and fracture network by taking the pipeline which is not 0 and penetrates through and is connected with boundary nodes as a passage pipeline; and constructing a flow conservation equation set based on network nodes, solving pore pressure by using a Jacobian iteration method, calculating fracture pressure, and applying the fracture pressure to the model to realize coupling of a stress field and a seepage field. According to the method, the advantages of particle discrete elements in calculation of rock mass fracture extension and the advantages of a pipeline network method in calculation of fracture seepage are fully exerted, and accurate simulation of rock mass fracture initiation extension, seepage channel recognition and seepage field calculation is achieved.

The invention discloses a testing device and a testing method for a permeability coefficient characteristic curve of wicking geotextile, and belongs to the technical field of permeability coefficient testing. A to-be-tested wicking geotextile and a soil layer are laid between an upper plate body and a lower plate body of a test unit of the test device; the two sealing covers are located at the two ends of the upper plate body and the two ends of the lower plate body respectively. Each of the first hollow column and the second hollow column comprises a hollow column section positioned above the upper plate body and below the lower plate body, the hollow column sections distributed up and down are communicated with a gap between the upper plate body and the lower plate body, and each hollow column section is filled with a soil body and forms a test soil column; the load output end of the load applying unit is used for applying a vertical load to the top of the test soil column and the upper plate body. The test device disclosed by the invention can really simulate the occurrence condition of the wicking geotechnical cloth in the roadbed engineering; the testing method based on the testing device can rapidly test the permeability coefficient of the wicking geotextile, and a characteristic curve of the permeability coefficient of the wicking geotextile is obtained.

The invention provides a device and a method for measuring the rock stratum permeability of a deep-buried tunnel, relates to the technical field of deep-buried tunnel construction survey, and aims to solve the technical problem that a conventional measuring device in the prior art is not suitable for measuring the rock stratum permeability of the deep-buried tunnel. According to the measuring device, a first plunger, a hydraulic mechanism, a water pumping mechanism and a second plunger are sequentially connected in a drill hole, the hydraulic mechanism is connected with the water pumping mechanism through a connecting mechanism, and the hydraulic mechanism is provided with a flow meter used for detecting the flow output by the hydraulic mechanism; the processor calculates the rock stratum permeability coefficient by receiving the detection signal of the flow meter and based on the detection signal of the flow meter so as to accurately measure the rock stratum permeability of the deep-buried tunnel, and meanwhile, the measuring device is simple in structure and convenient to install.

The invention discloses a test method for simulating the healing process of crack-containing expansive rock soil. The test method comprises the following steps: S1, preparing a compaction sample; s2, construction crack simulation; s3, assembling a fracture healing test instrument; s4, testing the expansive force and the permeability coefficient; and S5, testing dry density and moisture content distribution. According to the test method for simulating the healing process of the crack-containing expansive rock soil, gaps are formed around a sample and a pressure chamber, construction cracks are simulated, and axial and radial expansion pressures under different construction cracks are measured by adopting a vertically arranged force sensor and a radially arranged pressure sensor; the permeability coefficient of the crack-containing soil body is determined according to the volume of the injected water, the dry density distribution of the sample is determined by utilizing the water content and dry density test, and the test result can be used for comprehensively evaluating the crack healing degree.

The invention relates to the technical field of water conservancy geotechnical engineering, in particular to a core-wall rockfill dam seepage consolidation multi-field coupling dynamic prediction method, device and equipment, and the method comprises the steps: obtaining stress spatio-temporal data and material data in a core-wall rockfill dam seepage consolidation process; constructing a physical model of a seepage consolidation process in the core-wall rock-fill dam, a random field of a core-wall permeability coefficient and a compression modulus, and a prediction model of a combined random field, and constructing a loss function according to the physical model and the marked data; iteratively training the prediction model according to the stress spatio-temporal data and the material data, reversely iteratively updating the prediction model according to the loss function in the training process, and obtaining a trained prediction model after the training is completed; and predicting the seepage consolidation process of the core-wall rockfill dam by using the trained prediction model. Therefore, the problems that a finite element method and a deep learning method have certain limitations and are difficult to fit real monitoring data, so that a prediction result is inaccurate and the like in related technologies are solved.

The invention relates to a method for calculating an unsaturated permeability coefficient based on a soil-water characteristic curve, which comprises the following steps: establishing a soil-water characteristic curve model, setting a pore space in soil as a capillary bundle with non-uniform size by the model, the curve model comprising a Ropin-Rammer particle size distribution model and a void ratio; an unsaturated permeability coefficient model is established, the total permeability coefficient comprises capillary and non-capillary permeability coefficients, the capillary permeability coefficient is determined through an absolute saturation tortuosity constant, and the change of the non-capillary relative permeability coefficient is represented by a continuous differentiable empirical equation; according to the curve model and the unsaturated permeability coefficient model, determining a plurality of unsaturated permeability coefficient combination models, fitting each combination model to obtain a corresponding soil-water characteristic curve, and fitting each combination model into a calibration data set to obtain an optimal absolute saturation tortuosity constant value for evaluating the performance of different combination models; and determining an optimal unsaturated permeability coefficient model according to an evaluation result.

The invention provides an ice water accumulation body permeability coefficient dynamic calibration method which comprises the following steps: responding to a dynamic calibration instruction, analyzing an identification code, calling an environment parameter set and generating a permeability characteristic spectrum; selecting a calibration time period for storage; after verification is triggered, a verification parameter group is generated, real-time response data is received, a calibration result is output after interference filtering, correction, adjustment, feature extraction and similarity calculation, and the permeability coefficient is corrected if verification is passed. According to the invention, the permeability coefficient of the ice water accumulation body can be accurately calibrated in real time, the accuracy of glacier melt water seepage characteristic analysis is improved, and the reliability of glacier engineering and environment monitoring is enhanced.

The invention discloses a method and a system for rapidly and dynamically measuring the permeability coefficient of unsaturated soil. The method comprises the following steps: acquiring resistivity data, dielectric constant data and temperature data of soil in a target area; collecting the data according to a unified time resolution to obtain observation data; constructing a soil heterogeneous unit feature vector based on the collected data; dividing the feature vectors of the heterogeneous units of the soil to generate an initial permeability coefficient field; constructing a rock physical constitutive model; fusing observation data and a hydrodynamic model, combining with a rock physical constitutive model, dynamically updating a permeability coefficient field, and performing optimization by applying physical constraints; and finally outputting the updated permeability coefficient spatial-temporal distribution and uncertainty quantification result. According to the invention, the moisture change in the unsaturated soil can be monitored in real time, the moisture distribution condition of the soil can be accurately evaluated, and geological disaster risks such as leakage and landslide of the soil can be found in advance.

A calculation method of karst underground reservoir capacity curve based on hydrogeological parameters, including the following steps: hydrogeological exploration, determination of karst underground water reservoirs scope, determination of water storage space, determination of relevant hydrogeological parameters based on hydrogeological tests, and underground reservoir capacity analysis. The invention uses the unit water permeability and the borehole line karst rate that are very easily obtained through the borehole pressure (injection) water test and combines it with a small amount of water pumping test, thereby obtaining a correlation function relationship through regression analysis between the specific yield and the karst rate that are difficult to obtain and the unit water permeability or the permeability coefficient; the underground storage capacity at the corresponding elevation is calculated according to the specific yield or the karst rate and the underground storage capacity curve is obtained, which can improve accuracy and reduce errors.

The invention discloses a landfill well group optimization layout method based on permeability coefficient field inversion, relates to the field of well group optimization layout, and aims to utilize a finite element forward model to couple observation water level data and perform dimension reduction processing on grid nodes through characteristic decomposition. The technical core is that a bimodal distribution nonlinear mapping mechanism is introduced, and a low-dimensional parameter vector obtained by inversion is reconstructed into a high-resolution permeability coefficient field with clear space information of a fracture domain and a matrix domain. And according to the physical field distribution, a potential poor wetting area is positioned by identifying the position of a preferential flow channel and a hydraulic response blind area caused by the preferential flow channel. And based on the spatial relationship between the geometric centroids of the blind areas and the heterogeneous flow field, performing targeted correction and encryption on the initial well group coordinates. In this way, the technical problem that in the prior art, precise well spacing cannot be conducted according to the complex structure in the landfill is effectively solved.

The invention provides an intelligent grouting hole plugging pressure measuring and auxiliary decision making system based on permeability coefficient evaluation, and belongs to the technical field of subway tunnel engineering. Comprising a data acquisition module used for monitoring grouting pressure and grouting flow in real time; the stratum permeability coefficient evaluation module is used for calculating a stratum permeability coefficient according to the data acquired by the data acquisition module and transmitting a calculation result to the auxiliary decision making module; the pressure measuring system module is used for recording time data of grout pressure recovery after grouting and feeding back the time data to the auxiliary decision making module; the auxiliary decision-making module is used for combining the slurry pressure recovery time and the stratum permeability coefficient and providing a decision-making suggestion whether refilling is needed or not; and the visual interface module is used for displaying the real-time monitoring data and the decision-making suggestions generated by the auxiliary decision-making module so as to facilitate user operation. The application limitation of an existing subway tunnel engineering grouting technology in complex stratums is effectively solved, and the method has remarkable engineering application value.

A three-dimensional heterogeneous aquifer horizontal equivalent permeability coefficient multi-scale prediction method based on a residual network comprises the steps that a foundation pit dewatering two-dimensional pressure-bearing steady flow model is constructed, the influence of the size of a lenticular body on foundation pit dewatering flow field disturbance is evaluated, and the resolution ratio of a parameter prediction model grid is determined; based on actual drilling data and transition probability / Markov chain T-Progs, according to multiple deposition types formed by a binary deposition structure, a multi-layer aquifer structure, a coarse-grained deposition structure and a fine-grained deposition structure, a three-dimensional stratigraphic random structure model set is constructed, and three-dimensional stratigraphic section random slices are established; obtaining horizontal equivalent permeability coefficients corresponding to stratigraphic sections in various stratigraphic structures based on the underground water flow numerical model FloPy, and establishing a stratigraphic structure-equivalent permeability coefficient training set based on a neural network; a deep learning model is constructed based on the residual network ResNet50; and training, verifying and testing the equivalent permeability coefficient of the stratum section formed by the binary sedimentary structure, the multi-layer aquifer structure, the coarse grain sedimentary structure and the fine grain sedimentary structure.

The invention discloses a salt lake rock core permeation sample chamber for testing the permeation coefficient of a salt lake rock core sample, the salt lake rock core permeation sample chamber comprises an upper cover (2), an organic glass barrel (3) and a lower cover (4), a base (8), a latex film (11) and a pressurizing cap (7) are sequentially arranged above the lower cover (4) from bottom to top, and the latex film (11) sleeves the base (8) and the pressurizing cap (7), is tightened by a rubber band and is fastened by a hoop straining ring; and the lower cover (4) is provided with a water inlet and outlet valve interface (13) which is connected with a confining pressure controller and is used for controlling the peripheral annular pressure of the latex film (11), and foot pads (5) for supporting the sample chamber. A salt lake rock core sample is put into the latex film and then put into the sample chamber, a certain annular pressure is given to the sample through the water inlet and outlet valve interface, lateral seepage is prevented by controlling the annular pressure, and the situation that the permeability coefficient test result is unreliable due to the fact that the original structure state of the sample is changed under the action of large external force is prevented.

The invention discloses a post-excavation stratum reinforcement grouting effect visualization method based on multi-field coupling, and the method comprises the steps: firstly obtaining the stratum condition, rock mechanics data and grouting parameters of a grouting region, and carrying out the simulation calculation of the distribution condition of effective principal stress after excavation through a specific model; based on the distribution of the effective principal stress in the mechanical field in the porous medium, simulating and calculating the porosity distribution and the permeability coefficient after formation fracturing; analyzing a slurry diffusion path by adopting a specific model, and obtaining the overall change conductivity of the porous medium and the slurry through analog calculation; parameters of a resistivity hole lane combined monitoring system are determined according to the changing conductivity, and the potential value of each point position in the grouting reinforcement process is actually measured through the monitoring system; finally, the actually measured data and the model calculation data are compared and analyzed, the diffusion path and the reinforcement effect of the grout in the grouting reinforcement process are continuously obtained, and dynamic visualization of the stratum reinforcement grouting effect before and after excavation is achieved through comprehensive analysis of the multi-physics field coupling condition.

The present invention belongs to the technical field of generating heterogeneous structures of aquifers, and provides a method for generating heterogeneous structures by coupling a potential diffusion model and a random model. The present invention can utilize the prior distribution of aquifer structural parameters and the geostatistical parameters of permeability coefficients corresponding to different lithologies to generate heterogeneous structures of aquifers at different scales, and can constrain the spatial distribution of permeability coefficients according to the spatial distribution of large-scale lithological structures, thereby ensuring that the spatial distribution characteristics of permeability coefficients within different lithologies meet the given geostatistical distribution of permeability coefficients of different lithologies, thereby realizing the reasonable characterization of heterogeneous structures of aquifers at different scales.

An embodiment of the present invention discloses a numerical simulation method for the settlement of foundation pit engineering in water-rich strata, including: obtaining the calculation grid and soil parameters of the numerical model of foundation pit engineering in water-rich strata; performing numerical calculations on the calculation grid to obtain the distribution of stress and seepage field; calculating the permeability coefficient and compression coefficient under the current soil state; calculating the dynamic pore water pressure and steady-state pore water pressure; calculating the soil deformation according to the compression coefficient, dynamic pore water pressure and steady-state pore water pressure; and performing consolidation analysis according to the permeability coefficient. This embodiment can accurately predict the consolidation deformation of soil during complex construction processes.

The invention discloses a device and a method for measuring a vertical permeability coefficient of soil. The device comprises a water injection vertical pipe, a pressure guide pipe, a water level gauge, a water storage sleeve system and a soil accommodating cavity, wherein the pressure guide pipe sleeves the water injection vertical pipe and is connected with the water level gauge; the water storage sleeve system comprises a water outlet, a sleeve and a ventilation pipeline, the water outlet, the ventilation pipeline and a pressure guide pipe are contained in the sleeve, the top of the ventilation pipeline is sealed, the bottom of the ventilation pipeline is open, the upper end and the lower end of the water outlet are open, and the distance between the bottom of the water outlet and the bottom of the sleeve is smaller than that between the bottom of the ventilation pipeline and the bottom of the sleeve. The sleeve is also provided with an exhaust port and a water injection port; the soil containing cavity comprises an outer pipe and an inner pipe which are concentric and open up and down, the inner pipe is located in the outer pipe, the water injection vertical pipe is communicated with the inner pipe, and the projection of the ventilation pipeline in the soil containing cavity is located between the outer pipe and the inner pipe. The device is high in integration degree, convenient to carry and capable of being moved to an adjacent place at any time for multiple experiments.

The invention discloses a permeability coefficient field inversion method based on physical fusion large language model multi-agent, and belongs to the technical field of hydrogeological modeling and artificial intelligence crossing. The method aims at solving the problems that in the prior art, efficiency is low due to dependence on artificial experience, a pure data driving method lacks physical consistency, and closed-loop error correction cannot be achieved in large language model application. The method comprises the following steps: constructing a collaboration framework comprising a reasoning agent and an execution agent; generating an inversion code for calling a groundwater numerical simulator by the reasoning agent according to a natural language task; and the execution agent runs the code and obtains a simulation result, a code execution error and a simulation error are fed back to the reasoning agent through a double feedback mechanism of an inner-layer logic loop and an outer-layer physical loop, and the reasoning agent is driven to dynamically correct and iteratively optimize the code or an inversion strategy until the result is converged. According to the method, full-process automation of permeability coefficient field inversion is realized, and the physical rationality and reliability of an inversion result are ensured while manual dependence is reduced.

The utility model discloses an auxiliary device for detecting the permeability coefficient of concrete, which relates to the technical field of concrete detection and comprises a supporting bottom plate, supporting columns are arranged at four corners of the top end of the supporting bottom plate, and a supporting top plate is arranged at the top ends of the four supporting columns; a waste water recycling box is arranged at the bottom end of the supporting bottom plate, a detection base plate is arranged at the top end of the supporting bottom plate, multiple storage mechanisms are arranged in the detection base plate, and a water storage box is arranged on one side of the supporting bottom plate; multiple detection mechanisms are arranged in the supporting top plate, and a controller is arranged on one side of the top end of the supporting top plate. According to the utility model, the modularized and reasonable-structure design is adopted, so that high-efficiency management and assistance of links such as sample fixing, sealing, water feeding and discharging, data control and the like in the concrete permeability coefficient detection process are realized; water flow side leakage is effectively prevented by using stable storage, compression and multiple sealing structures, so that water flow can only pass through the interior of the detection barrel, and the accuracy of detection data is ensured.

The present invention proposes a numerical simulation method and system based on the coupling of rock fracture expansion and seepage, which belongs to the field of rock mechanics. Rock is regarded as a collection of particles and their mechanical contact with each other, and a triangulated network is constructed based on the center of each particle; according to the geometric characteristics of the triangulated network, a seepage pipe network containing the interior and the periphery is constructed, and the network nodes and boundary nodes are determined; the permeability coefficient is calculated according to the position of the particles on both sides of the pipe, and the pipes that are not 0 and pass through and connect the boundary nodes are used as passage pipes to form a through seepage channel and fracture network; a flow conservation equation group is constructed based on the network nodes, and the Jacobi iteration method is used to solve the pore pressure, calculate the fracture pressure, and apply it to the model to realize the coupling of stress field and seepage field. The present invention gives full play to the advantages of particle discrete element method in calculating rock fracture expansion and pipeline network method in calculating fracture seepage, and realizes the accurate simulation of rock fracture initiation and expansion, seepage channel identification and seepage field calculation.

The invention discloses a device and method for measuring a relative permeability curve of a soil body, the device comprises a cutting ring, a sleeve, a stainless steel electrode, a water delivery module, a vacuum drying system and a resistivity acquisition control module, the resistivity is monitored in real time through an electrode hole, and a sealing structure ensures that the system is stable. The method is based on an unsaturated seepage and electrical conduction theory and comprises the following steps: firstly drying a soil sample, then injecting water, collecting resistivity data, inverting a soil-water characteristic curve through a resistivity-moisture content-matric suction relation model, calculating a permeability coefficient in combination with a Darcy law, and fitting to obtain a permeability curve. The device and the method overcome the limitation that a traditional experiment is tedious in operation and prone to interference, have the advantages of being portable, easy and convenient to operate, high in automation degree, suitable for field measurement and the like, and can achieve efficient and accurate measurement of the permeability characteristic of the unsaturated soil body.

The application discloses an expansive soil free expansion rate and permeability coefficient field test device and method, relates to the technical field of expansive soil test, and aims to solve the problems of non-uniform expansive soil expansion potential discrimination standards and large test data discreteness in the prior art. The device comprises a ring cutter assembly, a water content measuring assembly, a displacement measuring assembly and a water supply assembly. The ring cutter assembly is used for fixing a test soil body; the water content measuring assembly is used for monitoring the water content of the soil body in real time; the displacement measuring assembly is used for recording the surface and deep displacement of the soil body; and the water supply assembly is used for controlling water injection. The test method comprises a test method and a numerical analysis method. The water content and displacement changes of the test soil body are monitored through water injection, the permeability coefficient and the free expansion rate of the soil body are calculated, the water content curve is fitted in combination with numerical analysis, the expansion coefficient and the saturated water content are solved, and finally, the free expansion rate of the soil body is determined, so that the free expansion rate and the permeability coefficient of the expansive soil are rapidly and accurately determined on site, the expansion potential is determined, and a reliable basis is provided for engineering application.

The invention discloses a shaft comprehensive geologic model construction method based on continuous quantitative grading of surrounding rocks. The problems that in shaft construction, surrounding rock strength grade evaluation representativeness is insufficient, permeability coefficient K dimensionless quantification is deficient, and high-permeability section systematic overestimation is caused are solved. The method comprises the following five core steps: 1, acquiring full-depth parameters of a drill hole, taking a rock core through drilling, and measuring lithology and permeability coefficients of surrounding rock; 2, calculating a lithology index Ai; 3, calculating a permeability coefficient by combining hydrological and lithologic parameters of the surrounding rock so as to obtain a hydrological index Bi; 4, coupling Ai and Bi to obtain a comprehensive index Ci; and 5, dividing the Ci into I-V levels, and generating a total depth statistical table containing the depth, the Ci and the levels. On-site application shows that the grade division of the surrounding rock is more accurate, and the time lt is divided in real time; the method is suitable for underground engineering such as a vertical shaft, an inclined shaft and a deep-buried tunnel needing grading of the surrounding rock of-200 m on the earth surface, and the popularization prospect and the economic value are wide.

The invention discloses a PRB permeability coefficient prediction method considering a dynamic heterogeneous mineral precipitation blocking process, and belongs to the technical field of permeable reactive barrier, and the method comprises the following steps: carrying out a visual microfluidic experiment of CaCO3 heterogeneous precipitation; performing parameter extraction according to a visual microfluidic experiment result; constructing a multi-parameter correction function and correcting a K-C equation based on a visual microfluidic experiment result and the extracted parameters; and dynamically updating the K-C equation based on the multi-parameter correction function so as to complete the prediction of the permeability coefficient. According to the method disclosed by the invention, the pore structure image and permeability data in the heterogeneous precipitation process are synchronously obtained in situ by utilizing a visual micro-fluidic experiment, so that a quantitative relation between precipitation characteristics and key constants in a K-C equation is established and is dynamically corrected, and accurate prediction of the PRB permeability coefficient is further realized.

The invention relates to the technical field of permeable concrete, and discloses a test method for the permeability coefficient of permeable concrete, wherein the method comprises the following steps: immersing a test piece in water for 24 hours; sealing four peripheral sides of the test piece by a membrane layer; placing the test piece in the middle of a cylinder cavity; inserting the lower part of a square cylinder into a water tank; and obtaining the permeability coefficient of the permeable concrete by a formula. By using the above method, water can be prevented from penetrating from the contact surface between the test piece and the square cylinder during the test, resulting in errors in the test data, thereby improving the efficiency and further improving the accuracy of the test results.

This application provides a method and system for predicting the full life cycle permeability characteristics of a dam based on its original data. The method includes the following steps: collecting dam design information and original permeability performance data of the dam at different times, and dividing the original permeability performance data into a training set and a validation set; dividing the full life cycle of the dam into different stages; selecting different types of data fitting functions to fit the permeability performance data of the dam material at different times and constructing different types of function models; constructing a three-dimensional finite element model of the dam based on the dam design information; calculating and obtaining the permeability coefficient of the dam based on the constructed different types of function models; performing inverse calculations on the different types of function models; and inputting the operating time of the dam to be predicted into the verified permeability performance prediction model to obtain the permeability coefficient of the dam. This application can improve computational efficiency, reveal the evolution of the permeability characteristics of the dam during operation, and has important application value for the safe control of seepage in dam projects.