96 results about "Stress variation" patented technology

The invention discloses a three-dimensional finite element simulation method for a complex slope excavation unloading process, which comprises the following steps of: 1) constructing a three-dimensional model of a complex slope, and establishing a finite element grid; 2) inputting boundary conditions of the model and material parameter information of each stratum; 3) calculating and simulating an initial stress field of the slope before excavation; (4) according to the initial stress field, the unloading load of the slope excavation part is calculated; (5) finite element calculation is conducted on stress deformation of the excavated slope; according to the method, the high-precision three-dimensional finite element model is established, various material parameters and actual boundary conditions are combined, the stress change and the unloading effect of the slope in the excavation process are simulated, the stress redistribution in the unloading process is accurately reproduced, the prediction precision of local instability and stress concentration areas is improved, and the prediction accuracy of the slope is improved. Therefore, a scientific basis is provided for safety assessment of slope excavation.

The invention discloses a tower footing side slope stability limit balance evaluation method under a lightning impulse condition, which comprises the following steps of: simulating a lightning stroke side slope tower test in a laboratory by inputting a potential sliding surface parameter and a rock-soil body material parameter of a certain side slope; calculating to obtain a conversion coefficient of the stress variation of the potential sliding surface of the side slope and heat generated by lightning impulse current, and further obtaining a calculation formula of the stress variation value of the potential sliding surface of the tower footing side slope of the tower under the lightning impulse condition, and taking the stress variation value of the potential sliding surface of the tower footing side slope of the tower under the lightning impulse condition as an input parameter; according to the method, the stability safety coefficient of the slope is calculated, the stability of the tower footing slope under the lightning impulse condition is evaluated according to the stability safety coefficient, accurate evaluation of the stability of the tower footing slope under the condition that the lightning impulse influences the stability of the tower footing slope is achieved, and the accuracy of slope stability analysis under the extreme weather condition is improved.

The invention discloses a method for simulating a mold temperature field and curing deformation through finite elements and a mold optimization design method based on the method. The finite element analogue simulation method comprises the following steps: firstly, modeling and simulating a mold grid; secondly, calculating equivalent thermal and mechanical parameters of the composite material by adopting a multi-scale homogenization method; then, a heat conduction model of the mold and the composite material blade is constructed and coupled with the curing dynamic model through temperature, and mold temperature distribution is simulated; and finally, establishing a mold thermal expansion and curing stress coupling model, and predicting thermal deformation and stress change of the mold. By identifying the weak area of the mold in the simulation process, the mold is optimally designed. By improving a mold temperature field distribution simulation method, optimizing a grid modeling process and introducing an accurate calculation method of equivalent material parameters, the precision of mold design and the controllability of a curing process are effectively improved, so that the problem of inaccurate mold temperature field distribution and curing deformation prediction is solved.

The invention discloses an ore pillar stability in-situ monitoring system which comprises a top plate grouting anchoring mechanism, a top plate settlement and weighting monitoring mechanism and an ore pillar circumferential deformation monitoring mechanism, and the system effectively fixes an upper structure on an ore body top plate through an air inflation pipeline, a grouting pipeline, an exhaust pipeline and a serial alarm circuit which are arranged in the system. Furthermore, real-time measurement of the stress variation and the self-degradation deformation of the pillar is realized through comprehensive cooperation of multiple sensors, a jack and a monitoring line, and a foundation is laid for the stability evaluation of the pillar. Based on the system, the invention further provides an in-situ assessment method for the stability of the jamb, the stable state of the jamb is divided into four grades of extremely high, high, medium and low risks according to a deformation-time curve and a stress-time curve of the jamb, multi-index comprehensive grading characterization of the stability of the jamb is realized, and a foundation is laid for differentiated treatment of a goaf jamb group. Reference and guidance are provided for avoiding goaf collapse accidents.

The invention belongs to the technical field of steel arch building monitoring, particularly relates to a large-span steel arch building monitoring and early warning method and system based on digital twinning, and solves the technical problems that the structural state of a large-span steel arch building cannot be comprehensively and accurately mastered in real time, and early warning and monitoring cannot be comprehensively and timely performed. According to the method, the three-dimensional twinborn model is constructed through the BIM technology, and the sensor data is mapped, so that the real-time data of different nodes of the large-span steel arch building can be intuitively and comprehensively obtained in real time. Compared with a traditional monitoring mode, the building structure state can be visually analyzed on the basis, the monitoring accuracy and comprehensiveness are greatly improved, and a scientific and systematic analysis process is established; through identification of stress data distribution conditions under different working conditions and comparison with material allowable stress, a stress change rate preset value, a safety margin reserved safety margin and the like, whether the structure is abnormal or not can be accurately judged, and an early warning signal is generated in time.

The invention relates to the technical field of bridge bearing capacity evaluation, in particular to a bridge bearing capacity accurate evaluation method, which comprises the following steps: acquiring stress data and deflection data of each position of a bridge under different static loads, and acquiring vibration data of each position of the bridge under the application of a dynamic load; according to the data distribution change and fluctuation degree of each position of the bridge under different static loads, a bridge stress change abnormal value and a bridge deflection data change abnormal value are obtained in combination with nonlinear change characteristics of the data, so that an abnormal coefficient of bridge stress deformation is obtained; the method comprises the following steps: acquiring significant values of abnormal vibration of each position under a dynamic load, further obtaining a comprehensive deviation coefficient of each position under the action of multiple loads, calculating a vulnerability degree value of each position of a bridge, adjusting a grid size in a bridge finite element model construction process, and counting bearing capacity of the bridge under different loads based on the bridge finite element model. The accuracy of the evaluation result of the bridge bearing capacity can be improved.

The invention discloses a composite truss string structure experiment monitoring method based on a composite sensing rib, the composite sensing rib with a self-sensing function is manufactured according to a fiber bragg grating, the composite sensing rib can monitor the stress change of the environment where the composite sensing rib is located in real time, the composite sensing rib is embedded in a center steel wire of a lower chord cable steel strand of a reduced scale experiment model, and the stress change of the environment where the composite sensing rib is located can be monitored in real time. The composite sensing ribs can directly sense stress changes of the truss in different construction stages, the stress changes of the reduced scale experiment model in different construction stages are monitored in real time through the composite sensing ribs, the accuracy and reliability of monitoring data are improved, problems and risks possibly occurring in the construction process can be found in time, and the construction efficiency is improved. According to the monitoring method based on the composite sensing ribs, construction personnel can adjust construction schemes and measures in time, smooth proceeding of the construction process is ensured, in addition, comprehensive monitoring can be achieved only by embedding a small number of sensing ribs into key parts of the composite string truss through the monitoring method based on the composite sensing ribs, and therefore the monitoring cost is reduced.

The invention provides a mass flow meter measurement compensation method and system combined with pipeline stress perception, and relates to the technical field of instrument correction. The method comprises the steps that an original stress data set is obtained; constructing a stress characteristic parameter set; constructing a sensor parameter set; based on the stress characteristic parameter set and the sensor parameter set, calculating the stress variation of the pipeline in the axial direction, the radial direction and the torsion direction to obtain a stress variation data set; utilizing the stress change data set and the sensor parameter set to establish a coupling model of the pipeline stress change to the vibration frequency and the phase signal of the sensing pipe, and calculating a corrected mass flow value; according to the comparison result of the corrected mass flow value and the calibration point in the long-term operation process, a parameter optimization algorithm is applied to conduct self-adaptive adjustment on the coupling coefficient, and coupling model optimization is achieved. The technical problem of measurement deviation caused by external stress, structural deformation and dynamic load in the prior art is solved.

The invention discloses a steel beam and steel arch deformation monitoring method and system, and relates to the technical field of deformation monitoring. Carrying out overall modeling analysis on the steel beam and the steel arch structure by using finite element software, determining a final unloading scheme, and monitoring deformation and stress conditions of the steel beam and the steel arch structure in the unloading process; in the unloading process, deformation and stress data of the structure are collected in real time through observation points, a stress and deformation time history curve of the structure in the unloading process is established, and deformation and stress change rules of the structure are obtained; comparing and analyzing a stress and deformation time history curve of the monitoring result with a construction simulation theoretical calculation value of a final unloading scheme; and performing early warning according to the comparison and analysis result. Finite element modeling, real-time monitoring and safety early warning are organically combined together, real-time monitoring of structural deformation is effectively improved, measures are taken in time to guarantee engineering safety, and comprehensive monitoring and safety evaluation of structural deformation of the steel beam and the steel arch are guaranteed.

The invention belongs to the technical field of welding stress control, and discloses an inner floating disc splicing stress parameter optimization method and system. Real-time working condition information such as the construction stage, the accumulated stress level, the overall structure rigidity and field environment parameters is combined with a dynamic adjustment mechanism of a stress optimization priority set; therefore, the problem that global optimization control is difficult to realize under multi-target conflict, construction stage evolution, cumulative stress change and field environment disturbance is solved, and the effect of realizing continuous balance and global optimization control among the targets in the whole construction period is achieved.

The invention relates to the technical field of composite material testing, and discloses a composite material testing device based on extreme temperature and a testing method thereof. The moving frame is slidably mounted on one side of the guide rail, and pull ropes are arranged on the upper surface and the lower surface of the moving frame; the at least two pull pressure sensors are symmetrically mounted at the bottom end and the top of the inner side of the movable frame; the connecting rope is fixed at one end of the tension and pressure sensor, and one end of the connecting rope is connected with a tested composite material; the device is simple and convenient to operate, greatly improves the testing efficiency, improves the temperature difference change by shortening the operation time, reduces the influence of the environment temperature, further improves the measurement accuracy under the extreme temperature change, can well verify the stress change formed by thermal expansion and cold contraction at the extreme temperature, and improves the practicability.

The invention relates to a variable-width volute spiral spring design method and a volute spiral spring, and belongs to the technical field of volute spiral springs.The variable-width volute spiral spring design method comprises the steps that S1, polar angles corresponding to plane spiral lines at different arc length positions are determined; s2, determining curvature radiuses corresponding to the planar spiral lines at different polar angle positions; s3, according to different curvature radius parts, the initial section width of the volute spiral spring is designed; and S4, the initial width of the volute spiral spring is adjusted according to the ratio of the radius to the half thickness of different parts, and uniform distribution of bending stress is achieved. The core of the method is that a corresponding width change rule is designed according to a change rule of bending stress along with curvature radius disclosed by a curved beam theory. By means of the method, the maximum bending stress of all the sections can be equal, and therefore the bearing capacity and stability of the volute spiral spring are improved.

The invention relates to the technical field of weld joint vibration fatigue life evaluation, in particular to a weld joint vibration fatigue life evaluation method based on a simplified modal structure stress method. The method specifically comprises the following steps: establishing a simplified finite element model of a welding structure without welding seam details, and calculating a structural mode of the simplified finite element model; a modal coordinate time history is obtained according to the structural modal, and the modal structural stress at the weld toe is calculated through a linear difference value; superposing the modal coordinate time history and the weld toe modal structure stress to obtain a weld toe structure stress time history; obtaining the change range and cycle index of the structural stress according to the rain flow counting statistics of the structural stress time history at the weld toe; equivalent structure stress is calculated; and calculating by adopting a main S-N curve method to obtain a damage and fatigue evaluation result of the welding seam. The modal structure stress at the weld toe is calculated through the linear difference, weld joint details do not need to be established, the workload of finite element model establishment can be greatly simplified, the modeling complexity is reduced, and the modeling efficiency is improved.

The invention discloses a microwave-quantum sensing slope full-dimensional monitoring method and system, and relates to the technical field of slope monitoring, and the method comprises the steps: obtaining a multi-source monitoring data set of a slope, obtaining a displacement-stress coupling coefficient according to the correlation between a displacement variation and a stress variation, obtaining a stability index in combination with a data variance, and generating a characteristic factor; further obtaining a characteristic index under the geological category; according to the characteristic indexes and the stability indexes of the monitoring points, different indexes are obtained to classify the monitoring points, the observed quantity and the state quantity of the monitoring subareas of the to-be-processed points are obtained, and an observation error covariance matrix is calculated; then Kalman filtering is carried out, a denoised current state value and a predicted value at the next moment are obtained, a coupling coefficient and a stability index are combined as input, a landslide risk level is obtained through a multilayer radial basis network model, and an emergency scheme corresponding to the landslide risk level is given. According to the invention, the slope full-dimensional early warning is realized by combining the coupling relationship between the earth surface and the underground.

The invention relates to the technical field of bridge engineering, in particular to a bridge creep deformation prediction and control method, which comprises the following steps: establishing a bridge structure finite element model; determining key section positions of the upper and lower edges of the bridge structure, and installing stress test elements at the key section positions; monitoring and recording the stress change of the upper and lower edges of the key section position in real time in the construction process; parameters in the finite element model are adjusted according to actually measured stress data, so that the error between the stress difference between the upper edge and the lower edge of the finite element model and an actually measured value is controlled within 1.0 MPa; generating a prediction result by using the corrected finite element model, wherein the prediction result comprises the creep deformation amount and the creep deformation direction of the bridge structure in the later period; and reserving a fastener adjustment space according to a prediction result. The scheme is used for solving the defect that in the prior art, the later creep deformation of a large-span beam arch bridge is difficult to accurately predict, and high-precision prediction of the later creep deformation of a bridge structure and dynamic parameter optimization and adjustment in the construction stage are achieved.

The invention discloses an elastic reverse time migration imaging method based on deviatoric stress characterization, and relates to the technical field of exploration geophysics. Deviatoric stress is introduced into a conventional elastic wave equation, and a speed-deviatoric stress elastic wave equation describing stress propagation characteristics is obtained through derivation; based on Hooke's law, P wave contribution in total partial strain is removed through partial strain decomposition, decoupling of P-S wave stress components is achieved, and correctness of amplitude, phase and physical unit of a decoupling wave field is guaranteed; and then a joint imaging condition with the average stress as a seismic source wave field and the multi-stress component as a receiving wave field is constructed, PP waves are subjected to normalization superposition through the average stress and the deviatoric stress, and PS waves are subjected to shear stress imaging. According to the method, the sensitivity to heterogeneity and local stress variation of underground media can be remarkably improved, P-S wave crosstalk and imaging noise are effectively eliminated, the imaging precision and resolution of a complex geologic structure are greatly improved, and a reliable technical means is provided for high-precision seismic exploration of complex oil and gas reservoirs.

The present invention relates to the technical field of tunnel seismic resistance, and discloses a method for calculating the seismic fortification length of a tunnel portal section. The method comprises the following steps: determining the range of the tunnel portal section; collecting and analyzing the mechanical parameters of foundation beam units in the tunnel portal section to obtain statistical analysis results and random distribution functions of the mechanical parameters; establishing a finite element model of the spatial variation distribution of the tunnel portal section by using the statistical analysis results and the random distribution functions of the mechanical parameters; introducing a tunnel lateral deformation coefficient and an axial deformation coefficient, and obtaining a displacement change of the tunnel under an earthquake based on the finite element model; performing a stress-displacement analysis on the tunnel portal section to obtain a maximum bending stress change and a maximum axial stress change of the tunnel portal, and then analyzing the obtained and determined seismic fortification length of the tunnel portal section. The present invention helps to optimize the tunnel structure design and determine the seismic fortification length of the tunnel by analyzing the stress of the foundation beam unit and the displacement change under an earthquake.

A method of controlling stress variation in a layer including silicon oxycarbide formed using a capacitively coupled plasma enhanced chemical vapour deposition system. The method includes providing a chamber comprising a platen for supporting a substrate, placing a substrate, upon which a layer comprising silicon oxycarbide is formable, upon the platen, introducing a gas comprising oxygen into the chamber, introducing trimethylsilane gas into the chamber, generating a plasma within the chamber, maintaining a temperature at which deposition takes place to less than 275° C., maintaining a pressure within the chamber in the range 1.5-3 Torr, and depositing the layer upon the substrate with a deposition rate >1.5 μm / minute.

The present disclosure provides a kind of based on the method and device for evaluating the safety degree of power plant dust remover structure based on monitoring, by the load variation and stress variation of the middle column, side middle column and angle column of dust remover are monitored in real time, the stress response ability of each key structural component is calculated, to judge the health state of dust remover layer by layer.When the health early warning value is lower than the preset health threshold, the system will timely issue an early warning, help to identify structural abnormalities, so that maintenance personnel can make accurate decisions.The method realizes the accurate early warning and real-time monitoring of power plant dust remover, significantly improves the safety and operating efficiency of the equipment, and effectively guarantees the stable operation of power plant.

The present application relates to the technical field of structural mechanics analysis, in particular to a spreader saddle stress nephogram generation method and system, comprising the following steps: based on the spreader saddle regional cable segment force measurement and spatial geometric information, constructing the initial stress of the saddle body grid, obtaining the stress concentration rate distribution through homogenization and normalization, extracting the gradient mutation grid to form a sequence of demarcation points, and generating the saddle area nephogram in the HSV space mapping according to the non-uniform color scale. The present application can adaptively identify the area with the most severe stress change by introducing the analysis of stress concentration rate and its spatial gradient, and no longer relies on the fixed color scale division method, but uses the high gradient position as a dynamic anchor point to construct a non-uniform color scale sequence. The processing logic tilts the color scale resolution according to the real stress response of the structure, making the color transition in the stress concentration area more fine, and the stress peak and gradient form are clearly presented. At the same time, a wider color scale interval is used in the stress gentle area for general expression.

The application provides a pipeline stress-aware mass flowmeter measurement compensation method and system, relates to the technical field of instrument correction, and the method comprises the following steps: obtaining an original stress data set; constructing a stress characteristic parameter set; constructing a sensor parameter set; calculating stress change amounts of the pipeline in axial, radial and torsional directions based on the stress characteristic parameter set and the sensor parameter set, and obtaining a stress change data set; establishing a coupling model of pipeline stress change on sensor vibration frequency and phase signal by using the stress change data set and the sensor parameter set, and calculating a corrected mass flow value; and according to the comparison result of the corrected mass flow value and a calibration point in a long-term operation process, applying a parameter optimization algorithm to adaptively adjust the coupling coefficient, so that the coupling model is optimized. The technical problem of measurement deviation caused by external stress, structural deformation and dynamic load in the prior art is solved.

The present application relates to the technical field of structural stability analysis, and particularly relates to a support and hanger instability early warning method fusing stress and angle data, comprising the following steps: synchronously collecting real-time axial stress and spatial pitch angle of a support and hanger node to generate a time series data pair; calculating stress change rate and angle change rate; constructing a stress-angle deviation index; setting a dynamic threshold according to a real-time thermal displacement speed of a pipeline; when the stress-angle deviation index is greater than the dynamic threshold for a duration exceeding an early warning time window T, determining that the constraint is invalid and triggering early warning. Compared with a traditional monitoring method relying only on stress or displacement, the present application can effectively capture early coupling instability signs such as structural stiffness degradation, gap slip and thermal expansion constraint disorder, and realize high-sensitivity response to dynamic structural behavior.

The invention discloses a method for evaluating the fatigue performance of a pipe joint, which comprises the following steps of: establishing an equivalent calculation model of a pipe joint forming process and an equivalent calculation model of a rotating bending fatigue process, simulating the rotating bending fatigue process, and identifying to obtain the stress level Ai of a guide pipe and the pipe joint at 0 moment; and identifying the position of the maximum stress change point of the conduit and the pipe joint and the stress amplitude Bi of the point. According to the material equal-life curve and the S-N curve, obtaining a relation curve of stress levels and stress amplitudes of the guide pipe and the pipe joint with the fatigue life of the pipe joint within 10 million times, and extracting a stress amplitude Ci corresponding to the stress level Ai in the relation curve; if so; ci, evaluating that the pipe joint meets the fatigue life requirement; and if Bi is greater than or equal to Ci, evaluating that the pipe joint does not meet the fatigue life requirement. The bending fatigue performance can be simulated and predicted, the verification period of the rotating bending fatigue test is remarkably shortened, and the method has good practicability.

1. Name of the product in this design: Drilling stress gauge (6-sided). 2. Purpose of this design: To measure stress changes in three directions within a borehole. 3. The key design feature of this product is its shape. 4. The image or photograph that best illustrates the design's key points: 3D view 1.

The present invention relates to a method for expressing physical properties when there is a change in strength in the plastic region of an elastic material, the method including: a region setting step of setting, in a first material and a second material obtained by pre-straining and heat-treating the first material, a basic region indicating the relationship between strain and stress in the first material and a change region indicating a portion of the change in stress according to strain due to factors caused by pre-straining and heat treatment of the second material; and a simulation step of expressing the relationship between stress change and pre-strain amount in the change region as a Boltzmann function, and deriving the relationship between strain and stress due to the second material as the sum of the stress according to strain in the basic region and the change region.

The application discloses a method and device for simulating the influence of fracturing construction on ground stress, which comprises the following steps: obtaining the design parameters and perforation parameters of a fracturing well; establishing a hydraulic pressure joint expansion model according to the design parameters of the fracturing well; establishing a numerical model of the influence of fracturing construction on a stratum according to the hydraulic pressure joint expansion model and the perforation parameters; and determining the ground stress variation law of the stratum around the fracturing well according to the numerical model of the influence of fracturing construction on the stratum. The method has the beneficial effects that the hydraulic pressure joint expansion model is established according to the design parameters of the fracturing well, the numerical model of the influence of fracturing construction on the stratum is established in combination with the perforation parameters, the ground stress variation law of the stratum around the fracturing well is determined according to the numerical model of the influence of fracturing construction on the stratum, and thus the ground stress variation law of the stratum around the fracturing well in the fracturing process can be obtained, which provides technical support for revealing the mechanism of the drilling interference caused by fracturing, and enriching and perfecting the related theory.

The present application relates to the field of material science and engineering application technology, specifically to a kind of metal material thermal mechanical fatigue life fast prediction method based on hysteresis energy density.First, hysteresis curve is used to calculate hysteresis energy density, then the quantitative relationship between shape coefficient, stress variation range and plastic strain range between low cycle fatigue and thermal mechanical fatigue is used, to achieve the purpose of predicting thermal mechanical fatigue hysteresis energy density under the same mechanical strain amplitude by low cycle fatigue, finally, energy accumulation damage model is used to predict thermal mechanical fatigue life.The method carries out two groups of experiments for low cycle fatigue and thermal mechanical fatigue respectively, realizes the prediction of thermal mechanical fatigue life under different mechanical strain amplitudes by low cycle fatigue, establishes the correlation between low cycle fatigue and thermal mechanical fatigue by using the similarity between them in the process of cyclic loading, effectively reduces the experimental amount required for thermal mechanical fatigue life evaluation, and is applied to the thermal mechanical fatigue life prediction of high-temperature alloy and vermicular cast iron and other metal materials.

The application discloses a steel structure installation measurement method, which comprises the following steps: establishing and maintaining a hierarchical dynamic measurement reference system, wherein the system comprises at least one fixed first-level absolute reference and one second-level partition dynamic reference arranged on a body of an installed steel structure; arranging strain sensors at key positions of the steel structure to monitor stress changes of the components in the installation process in real time; taking the second-level partition dynamic reference as a reference, measuring the geometric pose of a component to be installed; meanwhile, comparing real-time stress data obtained in the second step with theoretical expected values; and coupling analysis is performed based on the geometric measurement result and the stress comparison result in the third step, including generating adjustment suggestions for the geometric pose of the component when the stress deviation exceeds an allowable threshold, so that the installation tends to be in a low-stress natural state; and the target pose of the component installation is a predicted installation shape obtained based on simulation analysis and calculation of a construction process, and the shape is an intermediate state of the structure after bearing subsequent loads and deforming to tend to a design shape.

The invention discloses a method for calculating the creep effect of a steel-concrete composite structure. The method comprises the following steps: S1, calculating the stress states of concrete and a steel beam of a composite section of a steel-concrete composite beam under the action of external force when the steel-concrete composite beam falls for one time and does not creep; s2, calculating constraint reaction caused by concrete creep; s3, applying a constraining force on the creep calculation section in a reverse direction, applying a reaction force to the whole section, calculating stress change values of the upper edge and the lower edge of the concrete slab after the creep effect acts on the creep calculation section, and calculating stress change values of the upper edge and the lower edge of the steel beam of the steel beam section; and S4, calculating the stress state corresponding to the creep effect generated by the combined section by adopting an accumulation method. The method can solve the problem that a calculation result obtained by a traditional calculation method for the creep effect of the composite beam has a large deviation from an actual situation.

The invention discloses a fault plane total stress monitoring method, which comprises the following steps of: embedding a stress monitoring device into the center of an inclined plane of a to-be-measured body, calculating six independent stress components according to strain values of the to-be-measured body in different directions acquired by the stress monitoring device, and calculating normal stress and shear stress of a fault plane according to the six independent stress components. The fault plane total stress monitoring is realized; according to the invention, the stress monitoring device with six groups of strain rosettes and the base body is embedded into the inclined plane of the object to be measured, and the full stress monitoring of the fault plane is realized through the stress values measured by the six groups of strain rosettes, so that the accurate stress change characteristics during the slippage instability of the fault plane are obtained, and a basis is provided for preventing and controlling disasters induced by the slippage instability of the fault plane.