100 results about "Triaxial shear test" patented technology

The invention discloses a rock shear seepage coupling true triaxial test system, which relates to the technical field of rock mechanical tests, and comprises a host, a sigma 1 / sigma 2 direction loading module, a sigma 3 direction confining pressure module, a pressure chamber auxiliary system, a sample clamp, a pore water seepage system, a temperature system, a control module and a data acquisition and processing module, through servo closed-loop linkage double-pump loading in the sigma 1 / sigma 2 direction, synchronous output of the double pumps and coordination of pressure supply of the two oil cylinders by the controller, a strain correction algorithm is combined, stability of a stress loading center is guaranteed, strain measurement accuracy is improved, confining pressure is accurately controlled in the sigma 3 direction through a double-balance pressure chamber and a pressure regulation algorithm, and the stress measurement accuracy is improved. The pressure chamber is in full-automatic operation, manual steps are omitted, errors are reduced, efficiency is improved, a stress-free blank angle clamp eliminates friction interference, a seepage system supports a double-loading mode, a control module achieves multi-control-mode impact-free switching, a data processing module is combined with an elastic modulus calculation algorithm, rock mechanical parameters are accurately obtained, and the multi-field coupling test requirement is met.

The invention relates to the technical field of geotechnical engineering intelligence, in particular to a multi-field coupling intelligent triaxial test method and system combined with machine learning, and the method comprises the following steps: initializing a test device, and establishing a material parameter prior distribution function; defining a target test path and obtaining a target control sequence; acquiring real-time test data through a multi-source fusion sensing array, and preprocessing the real-time test data to obtain multi-dimensional feature fusion data; establishing an online parameter identification module to obtain real-time correction material parameters; establishing a heat-water-force multi-field coupling prediction model to obtain an optimal control sequence; acquiring latest test data, and performing rolling optimization on the model to establish a lightweight control model; and generating an intelligent control instruction to realize self-adaptive intelligent control of the triaxial test. According to the invention, through combination with machine learning, the spanning of the triaxial test from experience control to intelligent control is realized, and an intelligent technical means is provided for the research of the multi-field coupling characteristic of the geotechnical material.

The invention belongs to the technical field of geotechnical engineering and rock mechanics testing, discloses a stress-strain mixed control-based rock stable failure testing method, and aims to solve the problem that a stress path cannot be maintained and brittle failure cannot be inhibited simultaneously after rock peak strength is detected in an existing true triaxial test. The method comprises the following core steps: firstly, determining a target stress state and a strain growth rate threshold value; then hydrostatic pressure loading is carried out; loading and unloading at a fixed proportional rate in a stress control mode; and when the strain rate reaches a threshold value, switching to a stress-strain hybrid control mode, converting the maximum principal stress direction into strain control to stabilize the damage process, and dynamically coordinating stresses in the other two directions based on real-time feedback to enable the whole damage process to maintain a preset stress path all the time. According to the invention, the complete and stable test of the pre-peak-post-peak mechanical behavior of the rock under any complex stress state can be realized, and a key technical support is provided for accurately verifying the strength criterion and researching the failure mechanism.

This invention discloses a temperature-compensated seepage-shear coupling true triaxial testing apparatus and control method. The apparatus includes a pressure chamber, a shear box, a temperature control system, a pressure application system, and a temperature-displacement corrector. The shear box is housed within the pressure chamber. The temperature control system includes a heat transfer jacket, multi-point thermometers, and a temperature controller. The heat transfer jacket is fitted over the shear box, and the multi-point thermometers are located within the cavity. The pressure application system includes a confining pressure loading device, a pressure head, and a pressure controller. The confining pressure loading device injects a confining pressure medium into the pressure chamber, and the pressure head applies a force to the shear box. The temperature-displacement corrector is electrically connected to the temperature control system and the pressure application system. This apparatus features a temperature control system to precisely regulate the temperature during the test, thereby simulating deep environments at different temperatures. Furthermore, the temperature-displacement corrector dynamically corrects the force applied by the pressure application system, reducing additional forces caused by thermal expansion or contraction and improving stress control accuracy.

This invention relates to the field of deep learning technology, specifically to a numerical simulation method for true triaxial tests of coarse-grained soil materials based on principal stress effects. The method includes the following steps: acquiring three-dimensional geological parameters and boundary condition data of the coarse-grained soil material; and constructing a true triaxial finite element simulation model of the coarse-grained soil based on the three-dimensional geological parameters and boundary condition data. This invention utilizes a loading increment step size for trial calculations and calculates the reward function value based on the convergence state and iteration count of the trial calculation results to update the network parameters, enabling the control strategy to continuously evolve through interaction with the environment. This allows for the identification of dangerous regions with highly nonlinear constitutive relations or near-singular stiffness matrices. In these regions, the step size is automatically reduced to ensure computational convergence, while in stable regions, the step size is increased to improve computational efficiency. This solves the problem that traditional fixed step sizes or simple adaptive step sizes easily lead to computational divergence or excessive iterations under complex stress paths.

The invention discloses a true triaxial test device for rock heat conduction parameter in-situ measurement under a controllable temperature-stress coupling condition. The device comprises a triaxial pressure chamber, a temperature adjusting system, a double-electric servo loading system and an automatic control unit, the temperature adjusting system tightly surrounds the outer side wall of the triaxial pressure chamber, and the temperature applying value of the temperature adjusting system ranges from 10 DEG C to 150 DEG C; an upper seat and a base are arranged at the upper end and the lower end of the triaxial pressure chamber respectively, and a test space is defined by the triaxial pressure chamber, the upper seat and the base; the upper end of the side wall of the testing space is provided with an exhaust channel and a temperature sensor channel which are communicated with the outside from inside to outside, and the lower end of the testing space is provided with an oil conveying pipeline and a flat cable channel. The device has the advantages of being simple in structure, convenient to use and high in precision. The invention further discloses a method of the true triaxial test device for in-situ measurement of the heat conduction parameters of the rock under the controllable temperature-stress coupling condition.

The invention relates to the technical field of geotechnical engineering tests, in particular to a modular three-way confining pressure seepage loading box and a triaxial test system and method. The loading box comprises an outer box body, a loading seepage assembly and a force transmission assembly; the outer box body is internally provided with a sealing chamber for accommodating a test block, the outer wall of the outer box body is provided with a seepage interface communicated with the sealing chamber, and the top surface and the side surface of the outer box body are provided with loading holes; the loading seepage assembly is arranged between the test block and the outer box body and comprises a bearing plate and a loading plate, the bearing plate and the loading plate are respectively divided into a seepage plate and a non-seepage plate, the inner end face of the seepage plate is provided with a seepage channel, and the inner end face of the non-seepage plate is a plane and is in sealing contact with the test block; the force transmission assembly is installed on the loading hole of the outer box body, and the inner end of the force transmission assembly abuts against the loading plate. According to the loading box, three-way confining pressure seepage coupling tests under various working conditions are carried out with lower cost and higher flexibility on the premise that core triaxial equipment is not transformed.

The application belongs to the technical field of road engineering and relates to a static pressure demolding integrated geotechnical triaxial shear sample static pressure forming device and method. The device comprises a lower support module, a sample containing module, a force transmission module and a demolding elongation middle section. The lower support module comprises a static pressure demolding support, a sample containing barrel limiting hole penetratingly arranged at the top of the static pressure demolding support and a static pressure bearing table detachably arranged at the sample containing barrel limiting hole. The sample containing module comprises a sample containing barrel provided with a through hole communicating with the sample containing barrel limiting hole. The force transmission module is arranged at the upper opening of the through hole and used for applying static pressure to the soil sample to be statically pressed. The demolding elongation middle section is used for abutting against the force transmission module after the static pressure bearing table is removed from the sample containing barrel limiting hole, so as to push the geotechnical triaxial test sample out of the sample containing barrel limiting hole. Compared with the prior art, the application has the advantages of simple sample preparation, scientific method, small mold deformation and strong economy.

The invention discloses a rock-fill dam deformation analysis model updating method considering damming material parameter correlation, which comprises the following steps: firstly, collecting triaxial test parameters of a plurality of rock-fill dams with different dam types and lithology in the world, quantifying parameter correlation strength, constructing a priori knowledge model in combination with a variational auto-encoder, and mining a parameter internal correlation mode to provide physical constraints; secondly, generating a parameter sample by adopting a Latin hypercube sampling mode, constructing a data set in combination with finite element simulation, training a deep neural network agent model fused with spatial-temporal characteristics, and realizing high-precision mapping of damming material parameters and global deformation response; then introducing an elite archiving strategy to improve a multi-objective optimization algorithm NSGA-III; then DPK-VAE, a DNN proxy model and an improved NSGA-III are integrated, a multi-objective optimization framework is formed, and parameter optimization of the constitutive model of the damming material is completed so as to achieve updating of a rock-fill dam deformation analysis model; and finally, calculating a global deformation field and key safety indexes based on the updating model, and realizing thorough perception of the deformation character and the operation state of the dam body.

The invention discloses a covering layer foundation soil dynamic pore pressure-deformation indoor triaxial test method for reflecting an earthquake loading process, and belongs to the field of geotechnical engineering and earthquake engineering. Firstly, a numerical geometric model is created, and soil physical and mechanical parameters are input; secondly, carrying out power time history response analysis, outputting seismic dynamic stress response time histories of soil mass units at different positions and different depths in a numerical simulation result, and converting the seismic dynamic stress response time histories into test control loads; thirdly, carrying out an indoor dynamic test, loading a test control load, and collecting dynamic response data of the soil body under the earthquake action; and finally, on the basis of the dynamic response data, determining dynamic test results of all units of the covering layer by adopting an interpolation method according to stress states and dynamic strain amplitude interpolation, and completing dynamic characteristic analysis. According to the method, excessive simplification and blind test of a traditional test can be avoided, the authenticity and accuracy of the foundation soil dynamic test are remarkably improved, and the method is suitable for accurate evaluation of the dynamic characteristics of the ultra-deep soft covering layer foundation soil.

This invention provides a method and system for predicting the long-term strength of hard rock under the influence of dynamic disturbance frequency in true triaxial tests, relating to the field of deep engineering safety evaluation technology. The method includes: acquiring dynamic disturbance parameters, rock compression process data, and fracture morphology data from long-term dynamic disturbance true triaxial tests; constructing characteristic curves based on the rock compression process data; performing equivalent static mapping based on the dynamic disturbance parameters and characteristic curves to obtain the equivalent static stress state under the limiting frequency condition; fitting the equivalent static stress state to obtain the predicted long-term strength value under the equivalent static condition; constructing a model based on the characteristic curves and fracture morphology data to obtain a multi-dimensional criterion score; and judging and correcting the predicted long-term strength value based on the multi-dimensional criterion score to obtain the output result. This invention achieves quantitative characterization and accurate prediction of the long-term strength under true triaxial conditions for the influence of high-frequency, long-term dynamic disturbances.

The invention discloses a three-dimensional random field-based rockfill material space variability discrete element simulation method. The method specifically comprises the following steps of: 1, constructing a triaxial test discrete element model and determining related parameters; step 2, generating a three-dimensional random field based on Karhunen-Loeve expansion; and step 3, random interpolation and assignment of particle contact parameters. Aiming at the technical defect that the real mechanical behavior of the rockfill material cannot be accurately reflected due to the fact that homogeneous hypothesis, two-dimensional modeling and continuous medium analysis are generally adopted in the prior art, the method comprises the following steps: constructing a three-dimensional random field of the rockfill material and introducing a discrete element particle system; more reasonable and more practical description of rockfill material space variability, macroscopic mechanical characteristics and mesoscopic mechanism deformation is realized.

The invention discloses a triaxial shear strength testing method for a sewage discharge tunnel circular seam plugging ice plug body. The method comprises the following steps: S1, cutting a cylindrical sponge sample from medium-density sponge; s2, sleeving the side surface of the cylindrical sponge sample with a rubber membrane, and mounting a bottom steel support at the bottom; s3, injecting water into the cylindrical sponge sample in the rubber membrane to obtain a cylindrical sponge sample after water injection; s4, the cylindrical sponge sample after water injection is placed in a test block curing box and frozen at different set temperatures to form cylindrical sponge ice samples, and the set temperatures are the same as the average temperature of an ice plug body planned to be formed through liquid nitrogen freezing construction; s5, placing the cylindrical sponge ice sample in a triaxial testing machine, and performing a triaxial shear strength test under a set confining pressure to determine the shear strength of the cylindrical sponge ice sample under a simulated working condition; and S6, according to the test data in the S5, obtaining the triaxial shear characteristics of the cylindrical sponge ice at different set temperatures. The technical difficulty that an in-situ shear test cannot be performed on the ice plug body on site is solved.

The utility model discloses a frame pushing device for a rock test, and relates to the technical field of rock true triaxial tests. The device comprises a supporting frame, and further comprises a pushing part which is installed on the supporting frame and used for supporting, and a supporting part which is installed on the supporting frame and used for supporting the supporting frame. The number of the quick mounting parts is multiple, and the multiple quick mounting parts are all arranged on the pushing part; the number of the anti-falling parts is multiple, and the multiple anti-falling parts are located on the multiple quick mounting parts correspondingly; the plurality of quick mounting parts are distributed in an array, the anti-falling parts are distributed in an array, and the pushing part is used for supporting the plurality of quick mounting parts and the plurality of anti-falling parts. By arranging the quick mounting part, the problems that in the using process of the device, the frame main body and the mounting plate are inconvenient to quickly mount and dismount, workers need to spend a lot of time to position and mount the frame main body and the mounting plate, time and labor are wasted, burdens are brought to the workers, and the overall experiment progress is delayed are solved.

The application discloses a kind of building solid waste-red clay mixed roadbed filler permanent deformation estimation model and modeling, estimation method, the maximum dry density, optimum moisture content and CBR value of building solid waste-red clay mixed roadbed filler under different building solid waste incorporation rate are determined by compaction test, California bearing ratio test;Prepare the building solid waste-red clay sample of different building solid waste incorporation rate, carry out dry-wet cycle test to it, carry out triaxial test to the sample after preset dry-wet cycle number, determine its resilience modulus and permanent deformation;Establish the elastic deformation increment estimation model considering building solid waste incorporation rate, dry-wet cycle number comprehensively, and then obtain the permanent deformation estimation model considering stress-strain relationship, physical state, cycle loading number, building solid waste incorporation rate, dry-wet cycle number comprehensively, then the permanent deformation of building solid waste-red clay mixed roadbed filler is accurately and quickly estimated using the permanent deformation estimation model.

The invention relates to the technical field of railway roadbed engineering, and provides a heavy haul railway layered unsaturated roadbed working area depth determination method and system, and the method comprises the steps: obtaining a roadbed soil plastic strain function model containing temperature, stress and saturation through a dynamic triaxial test; the method comprises the following steps: establishing a three-dimensional train-track-roadbed coupling finite element model to carry out numerical simulation based on parameters such as train load, environment and roadbed ballast characteristics, extracting the maximum deviatoric stress and deformation of each depth layer, respectively converting the maximum deviatoric stress and deformation into dimensionless strain influence factors and deformation influence factors, and drawing a relation chart corresponding to roadbed depth; and obtaining a corresponding depth value through chart query, and determining the depth of the working area by taking the maximum value after verification. The method solves the problems that an existing method is insufficient in adaptation to high-speed large axle load, the environmental coupling effect is not considered completely, classification adaptability is lacked, and the depth determination accuracy is low, and efficient and accurate determination of the working area depth of the layered unsaturated roadbed of the heavy haul railway of different grades is achieved.

This invention discloses a method for calculating the bearing capacity of shallow foundations by integrating machine learning and nonlocal algorithms, belonging to geotechnical engineering. 1. The type of foundation soil is determined through indoor triaxial tests; strain-hardening foundation soils are analyzed; 2. Strain-softening foundation soils are analyzed; 3. A finite element model is established for refined simulation, followed by 7. 3. A constitutive model combined with a nonlocal algorithm is used for refined simulation, then proceeds to 4. 4. The influence range (DL) of the shallow foundation analysis is calibrated. f DL is determined by the softening rate control parameter β. f If suitable, proceed to step 7; otherwise, proceed to step 6. Step 6 involves building and training a machine learning agent model to ultimately obtain a suitable deep learning (DL) algorithm. f Shallow foundation analysis was performed with β1 and 7 to obtain the predicted value of the foundation bearing capacity. The present invention uses the above method to achieve efficient inversion of nonlocal parameters, thereby obtaining a reasonable predicted value of the shallow foundation bearing capacity.

The application provides a deep and shallow buried division method and system of underground engineering based on tunnel excavation effect, and belongs to the technical field of computer-aided design. The scheme comprises the following steps: obtaining an initial ground stress field of a tunnel area; sampling the tunnel area, carrying out a conventional triaxial test, and obtaining a full stress-strain curve of surrounding rock; obtaining ground stress information of a given engineering section according to the initial ground stress field of the tunnel area, establishing a three-dimensional numerical model of the tunnel, carrying out numerical simulation by using a constitutive model considering strain softening, and obtaining a stress field after tunnel excavation; and based on the full stress-strain curve and the stress field after tunnel excavation, deep and shallow buried division is carried out. The scheme fully considers that the occurrence of tunnel disasters under strong tectonic stress is significantly affected by true three-dimensional stress, considers the tunnel excavation effect, carries out deep and shallow buried division based on the true three-dimensional stress field, provides clear suggestions for the selection of the constitutive model of surrounding rock in the design process, and provides clear guidance for support design.

The utility model discloses a calcareous sand saturation device for a triaxial test, and relates to the technical field of indoor geotechnical tests of geotechnical engineering. The device comprises a supporting sample bearing structure, a sealing sample preparation structure, a hydraulic pneumatic structure and a gas-liquid supply structure. The supporting sample bearing structure consists of a base, a sliding rod, an upper sliding table, a lower sliding table and a top table; the sealed sample preparation structure comprises a sealing assembly and a sample preparation assembly; the hydraulic pneumatic structure comprises a hydraulic assembly and a pneumatic assembly and is used for controlling lifting of the sliding table and pressure maintaining and air exhausting of the sealing assembly. The gas-liquid supply structure provides CO2 gas and gas-free water for sample saturation and discharges redundant gas and liquid. According to the utility model, through the lifting type sealing assembly structure and the stepped sealing design, and the sequential action of the negative pressure pump, carbon dioxide gas and gas-free water, air in a calcareous sand sample is effectively discharged, a highly saturated state is quickly achieved, the accuracy of a subsequent triaxial test result is remarkably improved, and the test efficiency is improved. The sealing performance is excellent, the operation is simple, and the structure is stable.

An in-situ dynamic settlement test bench and method for the foundation soil is provided. The in-situ dynamic settlement test bench includes a vibration table system, a sensor embedded in the foundation soil, and a water injection trench around the foundation soil. A horizontal vibration load is applied to the lower foundation soil at an in-situ testing site by means of a vibration table, and the dynamic response of the foundation soil is measured through the sensors embedded in different positions, to reflect the seismic settlement deformation of the soil body. Dynamic settlement tests on soils include indoor dynamic simple shear, triaxial and torsional shear tests. A method is proposed for measuring the dynamic response and settlement deformation of the foundation soil by using a vibrator's vibration action on an in-situ soil column. Measurements of the acceleration response and seismic settlement deformation are taken for the foundation soil under in-situ condition.

The invention relates to the technical field of geotechnical engineering test sampling devices, in particular to a true triaxial undisturbed soil sample sampling device and method.The true triaxial undisturbed soil sample sampling device comprises a support assembly which comprises a C-shaped panel and a lower panel which are vertically and fixedly connected through a fixed supporting column, and a square hole is formed in the center of the lower panel; the two sampling balancing weights are detachably and symmetrically mounted on the two sides of the lower panel; the sampling part comprises a sampling mold which is mounted above the square hole in a lifting manner through a power source, and a panel cover for detachably mounting the sampling mold; according to the method, disturbance to the soil sample can be reduced, low-disturbance sampling is achieved, the original structure and stress state of the soil sample are kept, the requirement of a true triaxial test for the soil sample is met, mechanical parameters which are difficult to measure in a conventional test are obtained through the true triaxial test, a more accurate soil body constitutive model is established, the nonlinear relation among stress-strain-strength is described, and the accuracy of the soil body constitutive model is improved. And key technical support is provided for actual engineering.

The invention discloses a micro-nano robot grouting method and system in a rock true triaxial shear test, and the method comprises the steps: carrying out complex stress path loading on a rock sample in a true triaxial stress environment, and generating a three-dimensional fracture network; according to the three-dimensional fracture network, a micro-nano robot is driven to conduct global scanning on the fracture topological structure, and a fracture three-dimensional model is obtained; according to the crack three-dimensional model, the optimal grouting path of the micro-nano robot is planned; according to the optimal grouting path, the micro-nano robot is controlled to carry slurry to carry out directional grouting on the crack, and a sample obtained after grouting is obtained; scanning the grouted sample through intermittent low-dose micron nano-CT (Computed Tomography) to obtain grouting filling data; and according to the grouting filling data, after the optimal grouting path or grouting parameters are corrected in a closed loop mode, grouting is completed. According to the device and the method, accurate filling of micron-sized cracks is realized, and the test efficiency and the grouting success rate are remarkably improved.

The invention discloses a triaxial test device, and relates to the technical field of rock-soil mechanical property testing, the triaxial test device comprises a fixed frame, a loading device, a temperature control box, a side constraint assembly and a test rod, the loading device is fixedly arranged on the fixed frame, the temperature control box is fixedly arranged in the fixed frame, and a first opening at the top of the temperature control box is used for the input of the output end of the loading device; the side restraining assembly comprises a first restraining plate, a second restraining plate, a third restraining plate and a fourth restraining plate which are distributed in the circumferential direction, the restraining plates which are oppositely arranged are connected through pull rods, a to-be-tested piece is placed in an enclosed space of the restraining plates, and a testing rod is fixedly connected outside each restraining plate; one end, far away from the constraint plate, of each test rod can extend out of a second opening in the side part of the temperature control box, and a first displacement sensor is arranged on the fixed frame. The invention further discloses a rock-soil mechanical property testing method which is implemented by adopting the triaxial testing device. According to the invention, high test precision can be ensured, and the test reliability is high.

A dual-direction synchronous loading method for a true-triaxial test apparatus includes the following steps: Step S1, loading a sample and adjusting the sample at a center of a sample box and a rigid loading frame; Step S2, setting parameters and sending action instructions through a computer control panel; and Step S3, collecting load signals collected by each sensor acquired by a PID controller, and coordinating a size of triaxial dual-direction loading loads to realize a single instruction dual-direction synchronous loading. The method ensures that a rock sample is kept at a center of a pressure chamber before being loaded, so that a focus of a loading axis is always at a same position as a center of the sample in space, and the function of synchronous loading of two loading actuators in the same direction under a single instruction can be achieved.

The invention discloses a cohesionless soil damage ratio strength theory-based strength prediction method, which comprises the following steps of: establishing a strength criterion general expression of cohesionless soil in a triaxial compression stress state on the basis of a strain decomposition hypothesis and a unit energy consumption rate extreme value calculation model; converting the principal stress into a generalized stress parameter, and substituting the generalized stress parameter into a general expression of the strength criterion to obtain a generalized stress form of the strength criterion; establishing a damage ratio expression based on cohesionless soil strength envelope surface characteristics, and determining a corresponding empirical coefficient according to the cohesionless soil type to obtain an optimized strength criterion; and substituting the stress parameter of the target cohesionless soil into the optimized strength criterion, calculating to obtain a strength prediction value of the cohesionless soil, and verifying the prediction precision in combination with true triaxial test data. According to the method, low, medium and high full confining pressure ranges are covered, the plastic flow characteristics and the internal friction angle change rule of the cohesionless soil are accurately reflected, and high-precision strength prediction of the cohesionless soil under the complex stress condition is achieved.

The application discloses a kind of water-rich soft ground deep-buried underground water conveyance tunnel exterior grouting effect detection evaluation method, and relates to the technical field of tunnel engineering.The core is "laboratory verification-site detection-numerical evaluation", first through field soil sampling, dynamic triaxial test and grouting model construction, combined with nondestructive testing to establish "detection result-solid information-dynamic elastic modulus" mapping relationship;Then in situ test, impact image method and high-density surface wave method are used in engineering site, at grouting key node detection and quantization detection result and elastic modulus correlation, obtain static elastic modulus;Finally, according to design data, simulation model is built, bolt stress, transverse joint opening amount and shock subsidence displacement are calculated to determine grouting effect.The application organically integrates the three, forms a complete technical system, realizes water-rich soft ground deep-buried underground water conveyance tunnel grouting effect nondestructive accurate evaluation, and provides guarantee for engineering quality and operation safety.

The invention provides a gas extraction and grouting hole sealing simulation test method, and relates to the technical field of rock mass mechanics experiments. According to the method, specific test steps of field stress evolution path acquisition, true triaxial test, gas extraction simulation test, fractured rock mass grouting and hole sealing effect verification and the like are combined, multi-system data of all test stages are fused through a Bayesian fusion model, and data anomaly detection is performed in combination with an isolated forest and a DBSCAN algorithm. The reliability of an experimental result is evaluated by utilizing Monte Carlo simulation, experimental data is supplemented through Latin hypercube sampling, and closed-loop optimization of an experimental process is realized based on reinforcement learning. According to the method, the sample state judgment precision can be effectively improved, the reliability of an experimental result is improved, the experimental design is optimized, and accurate guidance is provided for data and experimental scheme optimization of a gas extraction and grouting hole sealing simulation test.

The present application belongs to the field of jointed rock mass dynamics and engineering technology, and particularly relates to an experimental method for studying dynamic mechanical properties of jointed rock mass under multi-stress state. The method is carried out by using a split Hopkinson pressure bar system combined with a loading system, and a coordinate system is established with the length direction of the split Hopkinson pressure bar as the X axis, the width direction of the split Hopkinson pressure bar as the Y axis, and the height direction of the split Hopkinson pressure bar as the Z axis. The loading system can load the loading chamber from the X axis, Y axis and Z axis directions respectively. The method specifically comprises the following steps: 1. preparing a cubic full-penetrating cross jointed rock mass sample; 2. selecting a corresponding test mode according to the site working condition; 3. biaxial test; 4. triaxial test; and 5. data analysis. The present application simulates the working conditions of the excavated area and the unexcavated area, thereby studying the dynamic mechanical properties of the rock mass under high strain rate and triaxial stress, and thus providing a basis for the design of underground engineering such as tunnels.

This invention provides a method and system for predicting pile end resistance based on a mudstone damage constitutive model, relating to the field of geotechnical engineering. Addressing the difficulty in quantitatively analyzing and calculating the bearing capacity of dynamically driven piles in mudstone foundations and the damage characteristics of the surrounding mudstone, this invention establishes a statistical damage constitutive model for mudstone based on the stress state-determined damage variable D and its association with rock failure criteria. Model parameters are determined according to triaxial test results, and the relationship between the critical damage variable and confining pressure is established. The damage characteristics of the mudstone surrounding the dynamically driven pile are analyzed, thereby calculating the pile end resistance and meeting the need for quantitative analysis of pile end damage characteristics.

This invention discloses an environmentally friendly, high-efficiency permeability-reducing composite material for sand and its applications. The environmentally friendly, high-efficiency permeability-reducing composite material comprises xanthan gum, nano-silica, and pectinase, used to improve the strength and reduce the permeability of sand. The invention first mixes sand and soil in equal proportions to obtain clayey sand, then incorporates the environmentally friendly, high-efficiency permeability-reducing composite material to obtain remolded sand. Permeability tests, triaxial shear tests, and microscopic tests on the remolded sand show that after incorporating the environmentally friendly, high-efficiency permeability-reducing composite material, gel material is uniformly distributed on the surface and within the pores of the remolded sand, forming a non-penetrating pore structure within it, reducing the permeability of the remolded sand. Furthermore, long-term curing can improve the strength and ductility of the remolded sand. The environmentally friendly, high-efficiency permeability-reducing composite material provided by this invention is environmentally friendly, efficient, low-cost, and applicable to multiple scenarios, with broad application prospects.