330 results about "Shear strength (soil)" patented technology

The invention relates to the technical field of design analysis, in particular to a soft soil deep foundation pit earth excavation construction scheme planning method and system.The soft soil deep foundation pit earth excavation construction scheme planning method comprises the following steps that a three-dimensional geological model is built based on geological exploration data, and rheological parameters, shear strength parameters and permeability coefficients of all soil layers are extracted to serve as layering parameters; according to the layering parameters and preset supporting structure rigidity parameters, a soil body rheological rate compensation coefficient is calculated, and an earthwork block excavation scheme with the grading thickness difference is generated; and in the excavation process, the displacement rate and pore water pressure data of the supporting structure are collected in real time, and when a monitoring value exceeds a preset threshold value, a dynamic adjustment instruction of the block excavation scheme is triggered. According to the method, the layering thickness and the blocking form are intelligently controlled according to different sensitivity levels, the matching coping capacity for soft soil instability inducements is improved, and the limitation that a single physical parameter dominates in traditional blocking design is broken through.

The invention relates to a method for identifying and extracting a potential sliding surface of a side slope under three-dimensional numerical simulation analysis, and belongs to the field of traffic side slope engineering. According to the method, a strength reduction technology does not need to be introduced, a rock-soil body shear strength criterion is not limited, after the slope stress field is obtained through numerical simulation calculation, the three-dimensional slope potential sliding surface can be efficiently, automatically and intelligently recognized and extracted, the obtained potential sliding surface conforms to a slope shear failure mechanism, and the method is suitable for large-scale popularization and application. The actual damage form of the three-dimensional slope in a real scene can be effectively displayed; according to the method, the sliding circumference boundary line of the three-dimensional potential sliding surface is determined firstly, and then the discrete points of the three-dimensional potential sliding surface are extracted within the range, so that intelligent identification and extraction of the three-dimensional potential sliding surface are facilitated. The method has the advantages of being wide in application range, high in efficiency, small in deviation, high in universality, good in effect, low in cost and the like, has the automatic and intelligent characteristics, and can provide a powerful scientific basis for slope potential instability range prediction and reinforcement area determination in actual engineering.

The invention provides a construction method and system of a rock-soil shear strength parameter prediction model, and relates to the technical field of model construction.The construction method comprises the steps that CT scanning data of a real rock-soil sample is obtained and preprocessed, and an irregular three-dimensional particle set for geometric modeling is obtained; performing particle surface roughness modeling analysis on the three-dimensional particle body set to obtain a surface roughness coefficient set of the three-dimensional particle body set; performing particle size cumulative distribution function segmentation processing and fractal dimension control on the surface roughness coefficient set to obtain a structure grading sample set; constructing a THMC multi-field coupling model based on the structure grading sample set to obtain a working condition particulate matter physical response parameter set; and performing a simulation experiment on the working condition particle physical response parameter set, and performing deep neural network modeling processing based on an experiment result to obtain a strength response model capable of predicting the cohesive force and the internal friction angle of the rock-soil body under any working condition input. According to the invention, the prediction efficiency and accuracy are significantly improved.

The invention provides a GNSS-based mountain area highway loess slope stability evaluation method and system, and relates to the technical field of loess slope stability evaluation.The method comprises the steps that firstly, a slope area is divided into grids, geologic feature data of each grid are obtained, super nodes are divided according to the geologic feature data, and the super nodes are divided into super nodes; monitoring points are determined, and the soil moisture content is monitored, so that the moisture content of the soil at different depths is analyzed; secondly, the original displacement is monitored through a GNSS, displacement correction is carried out based on the Fredld unsaturated soil shear strength theory, and the actual displacement is obtained; the influence of the accumulated rainfall on the soil body strength parameters is analyzed, and the soil body strength parameters are corrected in real time; coupling the corrected soil body strength parameter with the actual displacement, calculating a safety coefficient, and judging an early warning state according to the rainfall sensitivity coefficient; and finally, comprehensively judging the stability of the slope according to the early warning state. According to the method, through multi-parameter comprehensive analysis, the accuracy of slope stability evaluation is improved.

The invention relates to a method for identifying and extracting a potential sliding surface of a side slope in two-dimensional numerical simulation calculation, and belongs to the field of traffic side slope engineering. The method comprises the following steps of: determining an identified potential sliding surface boundary position as a potential sliding surface lower or upper edge boundary position according to a position relationship between side slope surface numerical value units with minimum and secondary minimum local safety coefficients; and finally, sequentially connecting the identified and extracted potential sliding surface points to obtain a two-dimensional side slope potential sliding surface. According to the method, a strength reduction technology does not need to be introduced, a rock-soil body shear strength criterion is not limited, the two-dimensional side slope potential sliding surface can be automatically and intelligently identified and extracted, the obtained potential sliding surface conforms to a side slope shear failure mechanism, and the actual failure form of the two-dimensional side slope in a real scene can be effectively displayed; the method has the advantages of being wide in application range, high in precision, good in universality, good in effect, low in cost and the like, and is used for providing a powerful scientific basis for slope potential instability range prediction and reinforcement area determination in actual engineering.

The invention discloses a high and cold arid region slope soil stability safety risk evaluation system and method, and relates to the technical field of slope engineering. The state of each side slope under multi-dimensional indexes such as freeze-thaw cycle frequency, dry-wet alternation index, wind erosion strength, shear strength, water content, porosity and fracture density is quantified, the feature similarity between any two side slopes is calculated, and then a side slope feature similarity matrix is formed. Based on the matrix, an unsupervised clustering algorithm (such as spectral clustering, similarity propagation and the like) can be adopted to divide a plurality of side slopes into similar subsets with structural characteristics similar to environmental response, and category attribution of risks is achieved. On the basis, structural variation analysis, historical instability statistics and central risk difference extraction are performed on similar slope samples, so that the internal instability tendency of the slope can be identified, and a risk prediction model suitable for the type of slope can be constructed through feature training.

The invention relates to the technical field of geotechnical engineering testing, in particular to a gravity type multifunctional in-situ testing device and a gravity type multifunctional in-situ testing method, and the testing device consists of three parts, namely a penetration system, a shearing system and a power system. The penetration system comprises a spindle-shaped full-flow penetration probe and a motion sensor. The shearing system comprises two arc-shaped shearing plates, a power shaft and a torque sensor. The power system comprises a moving empennage, a motor, a storage battery and an information collector. The device is hoisted to a test point to be thrown, so that the device freely falls and can penetrate into a soft soil layer, motion parameters of the device in the process of penetrating into the soft soil are tested and recorded, and the characteristics of the soil layer are obtained; and the arc-shaped shear plate is opened and rotated, so that the undrained shear strength of the soft soil layer is obtained. The test platform is convenient to arrange and high in test efficiency and accuracy. Excessive manpower is not needed, and the automation degree is high. Therefore, the technical problems that a test platform of an existing in-situ test device is difficult to arrange and low in automation degree can be solved.

The invention belongs to the technical field of ocean geotechnical engineering, and discloses full-strain range soil body strength characteristic testing equipment and a testing method for simulating a deep sea temperature and pressure environment. The system comprises an integrated probe, a stepping motor, a linear module, a hollow probe rod, a torsion module, a loading platform, a sample box, a water depth simulation system and a temperature control system. The hydraulic source and the temperature controller are used for simulating the deep sea low-temperature and high-pressure environment, the simulation effect is good, soil sample visualization is achieved, static sounding and vane shear tests are combined by designing the integrated probe, the soil permeability coefficient, the consolidation coefficient, the undrained shear strength and the sensitivity are measured, the precision and the efficiency of soil parameter analysis are improved, and the method is suitable for popularization and application. And data complementation, efficiency optimization and precision improvement are realized.

The invention relates to the technical field of geotechnical engineering safety monitoring and evaluation, in particular to a soft rock slope stability dynamic evaluation method which comprises the following steps: S1, acquiring slope environment parameters, construction parameters and geological basic parameters; s2, through simulation of the whole rainfall infiltration process, the spatio-temporal evolution characteristics of pore water pressure in a slope rock stratum are quantified, the aging relation between soil shear strength degradation caused by rainwater and slope displacement is analyzed, and a slope instability threshold calculation model is established; and S3, analyzing the monitored deformation and displacement cumulative effect of the slope and the migration characteristics of the rock stratum slip plane under the load action of the construction vehicle, and constructing a rock stratum instability risk assessment model based on the construction parameters. By comprehensively considering the influence of environmental parameters, construction parameters and geological basic parameters on the slope stability, dynamic evaluation and graded early warning of the slope stability are realized, a construction scheme can be pre-evaluated, and a construction reference is provided for safety management and control of a soft rock slope project.

The invention relates to a method for optimizing a newly-built anchor rod supporting system for slope expanding excavation by using residual anchor rods. The method comprises the following steps: preliminarily selecting a plurality of excavation schemes of different excavation slope angles according to the geometrical morphology of the side slope and the layout of anchor rods; calculating the excavation area and the residual length of the anchor rod of each scheme; calculating the theoretical ultimate uplift bearing capacity of the residual anchor rod based on the soil nail theory; midas GTS NX software is used for establishing a slope stability numerical simulation model considering and not considering the influence of residual anchor rod reinforcement, and a safety coefficient and anchor rod axial force distribution are calculated; by comparing the maximum axial force of the residual anchor rod obtained through numerical simulation calculation with the ultimate uplift bearing capacity obtained through theoretical calculation, the authenticity of the numerical simulation calculation safety coefficient is judged, and the true safety coefficient is sought; calculating a rock-soil body shear strength parameter adjustment coefficient according to the true safety coefficient to obtain an enhanced rock-soil body shear strength parameter, inputting the enhanced rock-soil body shear strength parameter into geotechnical engineering design software, and designing a newly-built support structure; and finally, technical and economic comparison and selection are carried out on the schemes, and the optimal scheme is selected.

The invention discloses flow-state solidified soil based on a waterproof consolidation agent and a preparation method thereof, and relates to the technical field of flow-state solidified soil, the flow-state solidified soil comprises original soil, the waterproof consolidation agent and water; the waterproof consolidation agent comprises a powder consolidation agent and a liquid consolidation agent; the liquid consolidation agent comprises emulsified silicone oil and emulsified asphalt. The powder component and the liquid component serve as the two-component consolidation agent, cement, slag, fly ash and other components in the powder consolidation agent can form a matrix structure in solidified soil, the stability of the solidified soil is improved, the compression resistance and shear strength of the solidified soil are enhanced, and the overall bearing capacity and stability of the solidified soil are improved; the liquid consolidation agent adsorbs the original soil and the powder consolidation agent to form a three-dimensional space framework, connection among soil particles is enhanced, the overall strength of the soil is improved, the compressive strength and the water stability of the solidified soil are better, and then the anti-freezing capacity of the solidified soil is improved.

The invention provides a main shock and aftershock sequence side slope vulnerability analysis method and system based on double response indexes, and relates to the technical field of earthquake side slope vulnerability analysis, and the method comprises the steps: building a GeoStudio side slope model according to the physical parameters of a side slope soil body, and obtaining the initial static safety coefficient and critical acceleration of the side slope; performing incremental dynamic time history analysis according to the main earthquake ground motion data, the slope model and the initial static safety coefficient of the slope to obtain a soil shear strength parameter value after the main earthquake; updating the initial critical acceleration of the side slope to obtain the critical acceleration of the side slope after the main earthquake; performing aftershock increment dynamic time history analysis according to the aftershock oscillation data and the critical acceleration of the side slope after the main shock to obtain a safety coefficient value and an accumulated displacement result of the soil body after the aftershock; and defining a vulnerability function based on the logarithmic normal cumulative distribution function to obtain a multi-level slope vulnerability curve. According to the method, the slope risk assessment precision and the visual decision-making capability are improved.

The invention discloses an improved Monte Carlo simulation-based slope system reliability analysis method, which comprises the following steps of: 1, determining statistical characteristics of a shear strength parameter cohesive force c and an internal friction angle phi of a slope soil body, and establishing a slope stability mechanical analysis model; 2, random samples formed by a large number of soil shear strength parameters are generated in a physical parameter space X, and an MCS sample library is formed; 3, randomly selecting a sample from the MCS sample library, calculating a safety coefficient by using the slope stability model, and obtaining a corresponding critical sample by using the sample and the safety coefficient; 4, determining the number of partial failure and safety samples in the MCS library by using the critical samples according to the internal relationship between the soil shear strength parameter and the slope safety coefficient, and removing the samples from the MCS library; and finally, repeatedly executing the steps 3 and 4 until the MCS library is an empty set, calculating the slope failure probability and identifying the key failure mode of the slope.

The utility model discloses a wrapped pile drilling and filling all-in-one machine which comprises a foundation mechanism and an executing mechanism, and the executing mechanism is connected to the foundation mechanism in a lifting mode. The basic mechanism comprises a power assembly, a walking assembly, a stand column and a supporting assembly, the stand column is arranged on one side of the walking assembly in a supported mode and supported through the supporting assembly, and the power assembly is arranged on the walking assembly and used for lifting the executing mechanism; the executing mechanism comprises a drilling assembly and a sleeve, the drilling assembly is arranged on the sliding rail of the stand column in a sleeving mode, and the drilling assembly is sleeved with the sleeve in a liftable mode; the power assembly comprises a main winch and an auxiliary winch. The all-in-one machine is suitable for treating mucky soil and soft plastic clayed soil foundations with undrained shear strength smaller than 20 kPa, and is particularly suitable for punching and pouring construction of saturated salinized soil foundation wrapped piles.

The invention discloses a shear strength parameter determination method considering earthquake action, which comprises the following steps: collecting a soil sample of a research area, air-drying, dispersing the soil sample into single particles, and sieving to obtain the stone content of the soil sample; the method comprises the following steps: preparing a compacted cylindrical sample from a soil sample, and placing the compacted cylindrical sample in a triaxial testing machine for a triaxial test to obtain static strength parameters of the soil sample; collecting seismic magnitude data of the research area, and determining the seismic magnitude of the research area; and according to the stone content, the static strength parameter and the earthquake magnitude, calculating the shear strength parameter of the research area under the earthquake action by adopting a shear strength damage cracking model. Based on PFC numerical simulation software, dynamic triaxial numerical simulation of the accumulation body is carried out and compared with an indoor test result, the change rule and numerical value of the numerical simulation result are close to those of the indoor test result, the parameter error is smaller than 50%, and the reasonability of the established accumulation body sample model and the calculated dynamic strength parameters is verified.

The invention relates to the field of underground engineering and rail traffic engineering, in particular to a deformation control method for a double-line shield tunnel to underpass an existing railway soft soil roadbed, which comprises the following steps: S1, determining a grouting reinforcement range; s2, pile position and grouting hole position lofting is conducted in the reinforcing area, and a groove is excavated; s3, construction is conducted after the MJS pile main machine is in place, and drill bit trial spraying is conducted before a drill rod is placed; s4, after the drill rod reaches the specified depth, jet grouting is conducted till the designed elevation is reached, and the MJS pile main machine is moved to the next pile position sample placing point; s5, after the MJS pile reaches the designed strength, a drilling machine is arranged in place, and a formed hole is drilled to the designed depth; and S6, grouting is conducted, and then grouting and grout stopping section construction is conducted. The method has the advantages that corresponding reinforcement measures are taken in combination with the model, the shear strength of the soft soil is improved, the shear damage risk of the soft soil is reduced, deformation of the soft soil roadbed is controlled in time, and safety and stability in the shield underneath pass construction process are ensured.

The present invention discloses a method and system for predicting the shear strength of unsaturated soil, and relates to the technical field of calculating the shear strength of unsaturated soil, and comprises the following steps: obtaining multiple hydraulic paths of any point on the soil water retention curve, obtaining multiple groups of moisture absorption path curve integrals and dehumidification path curve integrals of the point in its different hydraulic histories based on the multiple hydraulic paths, wherein the hydraulic paths include moisture absorption paths and dehumidification paths, and the hydraulic history is the repeated change process of dehumidification and moisture absorption of the point from the initial state to the research state; inputting multiple groups of moisture absorption path curve integrals and dehumidification path curve integrals of any point in the soil water retention curve in its different hydraulic histories and the saturated shear strength parameters of the test soil into the modified shear strength formula, obtaining the corresponding shear strength, and completing the prediction of the shear strength of unsaturated soil. The present invention can significantly improve the accuracy of the calculation of the shear strength of unsaturated soil, and is conducive to the popularization and application of the unsaturated soil strength calculation in actual engineering.

The invention discloses a soft soil foundation steel cylinder soil retaining structure displacement prediction system, which comprises a data acquisition module arranged around a steel cylinder soil retaining structure and used for monitoring construction data in real time; the data primary processing module is used for carrying out primary processing on the collected data; the data processing and analyzing module is used for performing data analysis and processing through an MSD method and calculating mobilization shear strength; the displacement prediction module is used for establishing a stress-strain relation model of the soil body according to the mobilization shear strength and predicting the displacement of the steel cylinder soil retaining structure; and the feedback adjustment module is used for providing construction adjustment suggestions according to the prediction result, dynamically adjusting construction parameters and optimizing the stress-strain relation model of the soil body. The invention further discloses a displacement prediction method for the steel cylinder soil retaining structure of the soft soil foundation. The displacement change of the retaining structure in the whole engineering period is accurately predicted, and the risk of structural instability is effectively prevented.

The invention relates to a slope instability probability evaluation method based on burial depth constraint space random field simulation, and belongs to the technical field of slope engineering. The method comprises the following steps: acquiring shear strength parameters c and phi at different buried depths of a slope soil body in a research area; the obtained shear strength parameters are expanded according to Gaussian process regression in combination with a radial basis function, the reliability of the expanded parameters is determined through K-S inspection, and cross correlation between c and phi is obtained; determining statistical characteristics of the c and phi expansion data; under the burial depth constraint condition, slope model determinacy research is carried out, a safety coefficient is calculated, the model is compared with a traditional model, and the difference between the potential slip plane of the slope under the burial depth constraint and the potential slip plane of the traditional slope is obtained; the traditional Monte Carlo simulation MCS is optimized; according to deterministic analysis and a random field theory, carrying out uncertainty research on the side slope under the burial depth constraint, and calculating the instability probability of the depth evolution random field side slope model.

The invention belongs to the field of geotechnical engineering, and provides a rock-soil body parameter intelligent test method and system based on artificial intelligence, and the method comprises the steps: obtaining the shear experiment data of a rock-soil body under different environment conditions, and calculating an equivalent shear weakening coefficient according to the experiment data; the shear modulus of the material is adjusted by weakening the shear strength of the rock-soil body through the water weakening factor; deriving a shear damage constitutive model under the action of the dynamic water head, and calculating the shear stiffness of the rock-soil body; establishing a Gaussian process regression model through experimental data and the shear stiffness obtained through calculation; carrying out global optimization on the Gaussian process regression model by adopting a self-adaptive stochastic optimization algorithm; dynamically adjusting model parameters; and outputting a final optimized rock-soil body parameter prediction result.

The invention relates to the field of deep horizontal displacement monitoring, and provides a deep horizontal displacement correction method and system based on the starting depth of an inclinometer. The method for correcting the deep horizontal displacement based on the starting depth of the inclinometer comprises the following steps: if the starting depth is the bottom of the inclinometer, calculating a first difference value between the corrected deep horizontal displacement at the orifice of the inclinometer and the absolute value of the horizontal displacement at the orifice of the inclinometer; if the starting depth is not equal to the bottom of the inclinometer tube, calculating a second difference value between the corrected horizontal displacement of the deep layer at the bottom of the inclinometer tube and the absolute value of the horizontal displacement at the bottom of the inclinometer tube; distributing the first difference value or the second difference value to each soil layer according to the reciprocal of the shear strength to obtain a first distribution error; determining a second distribution error of each monitoring point of each soil layer according to the number of the monitoring points contained in each soil layer; and obtaining a final displacement absolute value of each monitoring point according to the corrected deep horizontal displacement of each monitoring point. And the accuracy of deep horizontal displacement is improved.

The invention provides an in-situ test device and method for a shear strength index of simulated lunar soil, and relates to lunar soil detection equipment. A cross beam; a static sounding probe rod; the compacting cylinder group comprises a plurality of layered compacting cylinders which are detachably connected in sequence in the vertical direction, and the layered compacting cylinders are used for containing simulated lunar soil with different compacts; and the driving assembly drives the cross beam to vertically move and drives the static sounding probe rod to move, so that the static sounding probe rod is inserted into one of the layered compaction cylinders. The device has the beneficial effects that the simulated lunar soil with different compactness is contained in the plurality of layered compacting cylinders to simulate real in-situ undisturbed lunar soil, static sounding tests are performed on the simulated lunar soil with different compactness, and a physical model between the shear strength index and resistance of the simulated lunar soil is established to measure the shear strength index of the simulated lunar soil, so that the comprehensive performance of the simulated lunar soil is improved. In the moon exploration process, the test process is reduced, the test efficiency is improved, and the test cost is reduced.

The invention provides a soil body-structure interaction boundary damage quantitative testing device and method, and relates to the technical field of geotechnical engineering test.The soil body-structure interaction boundary damage quantitative testing device comprises a stress conduction boundary shear strength and rigidity combined testing structure and a testing system integrating a shaft confining pressure-temperature collaborative loading system and a monitoring collection and process control system; through an improved slurry sample preparation method, tight connection and constant contact area between the hollow columnar soil sample and the friction pile body are ensured, and the test sealing performance is enhanced through the elastic sealing design; the real-time measurement of the rigidity of different positions in the whole shearing process is realized by virtue of the excitation damage detection element capable of synchronously moving; according to the method, the constitutive model of the marine rock-soil stress conduction boundary domain is perfected, a reliable experimental basis is provided for foundation design of deep-sea engineering such as submarine pipelines and anchoring structures, and the method has important theoretical value and engineering significance for improving design scientificity and safety of deep-sea infrastructures and preventing and controlling submarine geological disasters.

The invention relates to a construction method of an embedded depth empirical formula under the limit of a high holding power anchor group. The construction method comprises the following steps: S1, establishing a solid model of a finite element model of the high holding power anchor group; s2, working conditions of the finite element model are designed in a grouped mode, and the influences of the seabed surface mooring chain loading angle # imgabs0 #, the mooring chain dragging speed # imgabs1 #, the seabed soil surface undrained shear strength # imgabs2 # and the soil body undrained shear strength gradient # imgabs3 # on the embedding depth of the large holding power anchor set under the limit are analyzed; s3, according to all working condition analysis results of the finite element model, the limit embedding depth of the large holding power anchor group is obtained, and an empirical formula # imgabs4 # of the limit embedding depth of the large holding power anchor group is obtained through multivariate function fitting; and S4, setting a verification working condition through an orthogonal test method, comparing the empirical formula with a finite element analysis result, and verifying the reliability of the empirical formula.

The invention discloses a test device for testing water-salt migration and shear strength of a novel partition layer of a salinized soil roadbed under THMC coupling conditions and a use method of the test device. The device comprises a water-salt migration system, a temperature control system, a vertical loading system, a horizontal shear system and a data monitoring system. Wherein the temperature system simulates roadbed temperature difference, the water-salt system reproduces internal water-salt migration, the vertical loading simulates an upper load, the horizontal shearing system directly measures the strength of a soil sample, and the data system monitors and records moisture, salt, temperature, stress and settlement changes in the soil sample in real time. The device can simulate a complex THMC coupling environment, reveal water and salt migration, temperature stress distribution and settlement rules, and can execute a direct shear test under the condition of keeping the original state of a soil sample. On the whole, the method has high feasibility, practicability and applicability, and a powerful tool is provided for salinized soil roadbed research.

The invention relates to the technical field of slope risk early warning based on slope data processing, in particular to a rock slope stability evaluation and early warning method, system, equipment and medium. The method comprises the following steps: firstly, obtaining an initial instability score and a slope stability type of a rock slope based on a gradient, rock-soil body shear strength and a structural surface development degree; then, considering the influence of potential slope instability in a rock slope group on the stability of a neighborhood slope, updating the initial instability score of the slope, and obtaining an initial comprehensive instability score of the slope; then, calculating an environmental instability score increment of the rock slope caused by rainfall, and updating the initial comprehensive instability score to obtain an updated comprehensive instability score of the rock slope; and finally, performing rock slope risk early warning according to a comparison result of the updated comprehensive instability score of the slope and an instability score threshold value. When the method is applied to the safety early warning of the rock slope, the accuracy and timeliness of the safety early warning of the rock slope can be improved.

The invention discloses a Duncan nonlinear shear strength relation linearization-based earth and rockfill dam slope stability subitem coefficient design method, which comprises the following steps of: firstly, according to an assumed linear shear strength index, carrying out dam slope stability subitem coefficient method analysis and calculation by adopting a simplification method; obtaining the initial subitem coefficient safety margin eta0 of dam slope stability and the initial stress state of each soil strip bottom surface, calculating a linear shear strength index corresponding to the Duncan nonlinear strength relationship according to the initial subitem coefficient safety margin eta0 and the initial stress state, carrying out dam slope stability subitem coefficient method calculation by adopting a strict stability analysis method again, and carrying out multiple iterations to obtain the stability of the dam slope. And obtaining the final value of the safety margin of the subitem coefficient of the dam slope stability of the earth and rockfill dam until the safety margins of the subitem coefficients obtained in two times are close. The method is a beneficial supplement for a dam slope and dam foundation anti-sliding stability analysis subitem coefficient method in existing rolling type earth and rockfill dam design specifications.

The present invention discloses a method for predicting the lateral deformation of a drainage board foundation under vacuum combined preloading, comprising the steps of calculating the initial undrained shear strength of the foundation soil, calculating dimensionless characteristic parameters, calculating the stress ratio of the soil at the end of the preloading, calculating the reference vertical strain of the soil under one-dimensional compression conditions, calculating the ratio of the lateral strain to the one-dimensional compressive strain of the soil, calculating the lateral strain of the soil, and calculating the lateral deformation of the foundation. This application is based on a relationship diagram between the stress ratio and the characteristic parameters and a quantitative relationship diagram between the lateral strain / one-dimensional compressive strain of the soil and the soil stress ratio / static earth pressure coefficient of the soil. The method can quickly calculate the lateral deformation of the drainage board foundation under vacuum combined preloading, providing a reference for the design of drainage board foundations treated with vacuum combined preloading.

The invention discloses a multi-scale research method for soil body strength degradation under the dry-wet cycle effect. The multi-scale research method comprises the following steps: S1, preparing a sample from collected test soil under the dry-wet cycle effect; s2, testing the macroscopic shear strength of the soil body by using the triaxial sample prepared in the step S1; s3, the cutting ring sample prepared in the step S1 is used for soil microcosmic fracture testing; s4, carrying out a soil body micro-pore test by utilizing the microstructure sample prepared in the step S1; and S5, analyzing the soil body strength degradation rule of the collected test soil under the dry-wet cycle action by using the test results of the soil body macroscopic shear strength test, the soil body microcosmic crack test and the soil body microcosmic pore test. According to the method, through multi-scale analysis, related enterprises can more comprehensively evaluate the degradation rule of the soil body under the dry-wet cycle effect, so that an engineering construction design scheme is optimized, and the risks of landslide, collapse and other engineering accidents caused by soil body strength reduction are reduced.

The invention discloses a pile-soil interface shearing algorithm considering related characteristics of a soil body state. The pile-soil interface shearing algorithm is suitable for calculating pile side friction resistance after a pile foundation is driven in offshore engineering. The method mainly comprises the following steps: (1) transferring stress and strain tensors obtained by calculation of a constitutive model considering that rigidity and strength parameters of a soil body change along with the state of the soil body to a soil and structure interface shear model; (2) assuming that a soil and structure contact interface is in a simple shearing state, and iteratively solving the normal strain of the interface; and (3) calculating the normal stress and the interface tangential stress through the calculated normal strain, and considering the influence of the strength change of the pile-side soil body on the interface shear strength. According to the method, the soil constitutive model related to the state is introduced on the basis of traditional coulomb friction, constitutive responses of the soil in different confining pressure and shear strain states can be reflected, pile-soil interface mechanical behaviors are calculated, and the influence of soil characteristics on the interface behaviors is reflected more reasonably.