41 results about "Stress measurement" patented technology

The invention relates to the technical field of material mechanical property testing, in particular to a method for measuring residual stress of a metal component. According to the technical scheme, the method for measuring the residual stress of the metal component comprises a working process for measuring the residual stress of the metal component; according to the method, a technical path of multi-modal data assimilation is adopted, and a mechanical release mechanism of a drilling method and an ultrasonic stress measurement technology are deeply fused to calibrate and correct mass sound velocity data obtained by carrying out rapid ultrasonic scanning on the whole component on site, so that the precise measurement of the residual stress state of the metal component is realized, and the measurement precision is improved. According to the method, data authority and high credibility of a drilling method in a key area are reserved, the advantages of high efficiency and wide coverage of full-field measurement of an ultrasonic method are brought into full play, and efficient and accurate stress information is provided on the premise that components are not excessively damaged.

The invention relates to the technical field of stress measurement, in particular to a steel enclosing purlin stress real-time monitoring method based on the Internet of Things and a storage medium, and the method comprises the steps: obtaining the local neighborhood similarity of stress values of different stress monitoring points on a steel enclosing purlin at different moments; the method is used for classifying the stress values of all monitoring points at all moments before the current moment, obtaining a plurality of sets, merging the stress values of all the stress monitoring points at the current moment into each set, obtaining a plurality of update sets and the abnormal probability of the stress value of each stress monitoring point at the current moment, and calculating the abnormal probability of the stress values of all the stress monitoring points at the current moment. And performing data stripping on the update set to obtain a plurality of secondary update sets so as to obtain the abnormal probability of the stress value of each stress monitoring point at the next moment at the current moment, thereby judging whether to send out an early warning prompt or not. According to the method, the abnormal data can be accurately identified through comparison between the real-time data and the historical data.

The invention provides a volume coefficient matrix rapid solving method for residual stress field inference and application, and relates to the technical field of material stress measurement and characterization. The method comprises the following steps: S1, calculating an inverse matrix of a non-constraint node sub-stiffness matrix of an initial state of a part; s2, calculating a non-constraint node sub-stiffness matrix variable quantity caused by part material removal in each process step; s3, calculating an inverse matrix of a non-constraint node sub-stiffness matrix of the part in each process step; s4, calculating a volume coefficient matrix of the part in each process step; and S5, assembling the volume coefficient matrixes of the parts in each process step into a volume coefficient matrix. The method solves residual stress in residual stress field inference by utilizing a volume coefficient matrix. According to the method, the calculation efficiency of the volume coefficient matrix is remarkably improved, and the problem of low calculation efficiency of the volume coefficient matrix in the prior art is effectively solved.

The invention provides an intelligent detection method and system for absolute stress of a steering axle of a port machine, and relates to the technical field of stress measurement and detection. Carrying out synchronous correction and feature modeling on the collected data, and constructing an absolute stress calculation and intelligent analysis model; screening a structure benchmark operation interval based on the operation data, constructing a benchmark stress reference state, and evaluating the stability of the structure benchmark; on the basis, multi-axis decomposition is carried out on the absolute stress, a multi-axis stress decoupling coefficient is calculated, and multi-axis stress safety judgment and coordinated regulation are achieved; and further combining the stress time sequence evolution characteristics and the fatigue accumulation effect, evaluating the long-term stress evolution risk of the structure, and implementing steering, loading and maintenance strategies when the risk exceeds the limit. According to the method, online sensing, risk early warning and closed-loop optimization of the absolute stress of the steering axle are realized, and the operation safety and the structural reliability of the port machinery are improved.

The invention discloses an uncalibrated stress measurement method and device based on ultrasonic longitudinal wave and incremental deformation mechanics, and relates to the technical field of ultrasonic nondestructive testing, and the method comprises the steps: obtaining an ultrasonic longitudinal wave time domain signal at a detection point of a to-be-detected test piece and the thickness of the to-be-detected test piece; determining the propagation time of the longitudinal wave in the test piece to be detected based on the ultrasonic longitudinal wave time domain signal; based on the thickness of the to-be-detected test piece and the propagation time, determining the propagation speed of the ultrasonic longitudinal wave in the to-be-detected test piece; and determining a stress value at the detection point of the test piece to be detected according to the propagation velocity. According to the invention, the problem of measuring the high-order elastic constant of the material can be avoided, and the dependence of a stress measurement result on a calibration result is avoided.

The invention provides a bridge supporting column stress measurement method based on structure collaborative stress analysis, and belongs to the technical field of stress measurement, and the method comprises the steps: collecting the stress, strain and displacement data of each bridge supporting column in real time; calculating a local stress index of each bridge support column based on the collected real-time data; according to the connection relation between the bridge overall structure parameters and the bridge supporting columns, a structure collaborative stress model is established; calculating a cooperative stress correction index of each bridge support column; and comparing the cooperative stress correction index with the dynamic stress evaluation interval, performing trend analysis in combination with historical data and environmental factors, judging whether a structural risk exists or not, and sending out an early warning signal when the structural risk exceeds a threshold value. According to the method, a structure collaborative stress analysis mechanism is introduced, the influence of the overall stress state of the bridge on a single bridge supporting column is comprehensively considered, key structure risk points can be recognized more accurately, and the reliability and early warning capacity of bridge safety monitoring are improved.

The invention relates to a device and a method for transmitting a measured value aiming at geotechnical engineering anchoring property detection, which belong to the technical field of transmission of measured values, and are capable of accurately denoising and eliminating redundancy through pre-treatment operations such as measured value cleaning and the like, so that high-performance and credible stress measured value conditions are provided for subsequent analysis and determination of a stress measured value of an anchor rod, and the accuracy of the stress measured value is improved. According to a numerical value source, pre-processed numerical values are grouped and structured to form a synthetic packet, then the synthetic packet is divided into a first group and a second group of equal synthetic packets according to whether the same numerical value exists, different coding processing methods are respectively applied, and a more detailed coding method improves the reliability of a stress measurement value, so that the reliability of the stress measurement value is improved. The defects of insufficient transmission efficiency, loss of the stress measurement value and the like caused by transmission in an unstable channel period are prevented, the transmission efficiency and credibility of the stress measurement value are obviously improved, the stress measurement value of the anchor rod can be correctly transmitted to a remote host in real time, and the stress measurement value of the anchor rod can be remotely monitored more accurately.

The present disclosure provides a detection system comprising: one or more magnetic probes configured to acquire stress measurements at a plurality of points along a surface of a sample, where stress data is acquired at a plurality of angles for each of the plurality of points; and a computing system communicatively coupled to the one or more magnetic probes, the computing system including at least one data processor and a memory storing a plurality of predetermined material calibration parameters and material characteristics of a plurality of materials and instructions, the instructions, when executed by the at least one processor, cause the at least one processor to perform operations including receiving stress measurements from the one or more magnetic probes, comparing the stress measurements to the material calibration parameters and material characteristics, determining a material characteristic of the sample based on the comparison, and determining the material characteristic of the sample based on the determined material characteristic. And providing the material characteristics of the sample to a user interface display.

The embodiment of the present application relates to the field of in-situ stress measurement, and discloses a comprehensive determination method for the reliability of different in-situ stress measurement methods in the same area. The comprehensive determination method includes: obtaining first in-situ stress measurement data based on the first in-situ stress measurement method; obtaining second in-situ stress measurement data based on the second in-situ stress measurement method in the same area; using the Bayesian linear regression method to model and align the data of the first in-situ stress measurement data; using the Bayesian linear regression method to model and align the data of the second in-situ stress measurement data; drawing a first probability density map based on the first in-situ stress measurement data after data alignment, drawing a second probability density map based on the second in-situ stress measurement data after data alignment, and comparing the similarity between the first probability density map and the second probability density map. The comprehensive determination method uses Bayesian linear regression to realize the reliability determination of the test results obtained by using multiple different in-situ stress measurement methods in the same area.

The invention discloses an uncalibrated stress measurement method based on ultrasonic surface wave and incremental deformation mechanics and a related device, and relates to the technical field of ultrasonic nondestructive testing. The method comprises the following steps: exciting an ultrasonic surface wave signal through an excitation sensor arranged on the surface of a test piece to be detected; acquiring an ultrasonic surface wave time domain signal in a stress state by a receiving sensor; the wave velocity is calculated by combining the distance between the sensors and the propagation time, and then the stress value on the detection path is determined according to an ultrasonic surface wave velocity-stress formula. The wave velocity-stress formula is derived from a control equation established based on an incremental deformation mechanics theory and surface wave propagation characteristics, the dependence on a high-order elastic constant in the prior art is avoided from the source, zero-stress test piece calibration is not needed, and the constraint of a calibration result is thoroughly got rid of. According to the method, the advantages of no damage, no radiation and simple and convenient equipment of ultrasonic detection are continued, the applicability and the generalization performance are remarkably improved, and the absolute stress measurement on the surface and the near surface of the test piece can be accurately realized.

The present invention provides a terahertz time-domain undersampling spectroscopy method and system for stress measurement. Undersampling is performed on a stressed specimen to obtain at least one set of terahertz time-domain undersampling spectral data. This data is then processed to obtain an error function describing the undersampling error caused by stress modulation. This error function is then processed to calculate the stress modulation coefficient and the change in the peak position of the terahertz signal. The specimen stress is then calculated based on the stress modulation coefficient and the change in the peak position of the terahertz time-domain spectrum. The present invention has the beneficial effects of effectively reducing the sampling window, minimizing delay line displacement, increasing measurement speed, and significantly shortening measurement time, while ensuring stress measurement accuracy.

The application provides a volume coefficient matrix fast solving method for residual stress field deduction and application, and relates to the technical field of material stress measurement and characterization. The method comprises the following steps: step S1: calculating the unconstrained node sub-stiffness matrix inverse matrix of the initial state of a part; step S2: calculating the unconstrained node sub-stiffness matrix change caused by material removal of the part at each step; step S3: calculating the unconstrained node sub-stiffness matrix inverse matrix of the part at each step; step S4: calculating the volume coefficient matrix of the part at each step; and step S5: assembling the volume coefficient matrix of the part at each step into a volume coefficient matrix. The method solves residual stress by using the volume coefficient matrix in residual stress field deduction. The application significantly improves the calculation efficiency of the volume coefficient matrix, and effectively solves the problem of low calculation efficiency of the volume coefficient matrix in the prior art.

The application provides a gear dynamic stress measurement data outlier elimination method under a small sample, comprising the following steps: step 1, determining a gear dynamic stress measurement position and a number requirement; step 2, determining a vibration excitation order of the gear dynamic stress measurement data; step 3, classifying and arranging the gear dynamic stress measurement data; step 4, preliminarily screening abnormal data based on a quartile range algorithm; step 5, determining a statistical characteristic value of the dynamic stress test data; and step 6, finally determining the abnormal data based on a Grubbs criterion method. The method can effectively reduce the influence of gross errors on the mean value and standard deviation of small sample data, improve the identification reliability of abnormal data, and improve the accuracy of gear fatigue risk assessment; the method is fast and convenient, easy to be programmed, improves work efficiency, and is helpful to reduce the cost of manpower and financial resources.

The invention discloses a drill hole plane stress measurement method based on hole circumference relative displacement change. The method comprises the following steps: step 1, drilling a to-be-measured drill hole at a preset position to a preset measurement depth; 2, a mounting hole is concentrically drilled in the bottom of the drill hole, and a plurality of deformation meters used for measuring the relative displacement of the hole periphery are mounted on the hole periphery of the mounting hole; and step 3, the sleeve core is adopted to remove the to-be-measured drill hole, the relative displacement change of the periphery of the deformation meter mounting hole is obtained through the deformation meter in the removing process, and the plane stress state of the rock around the to-be-measured drill hole is obtained through relative displacement calculation. The method is simple in measurement and high in anti-interference capability, and the stress state of the drill hole can be calculated only by testing the relative displacement of three points around the hole.

The invention relates to a weighing-free construction method for a flat-turning bridge based on an intelligent supporting leg device, which takes the intelligent supporting leg device as a core technical carrier, monitors the stress condition borne by a supporting leg in real time through a built-in stress sensor, and judges whether the stress state of a turning structure meets a locking condition or not; meanwhile, a stress sensor arranged in the intelligent supporting foot device is used for measuring and recording an initial stress value of the intelligent supporting foot device, and the initial stress value serves as basic data of follow-up analysis. Before a bridge rotates, temporary locking of the intelligent supporting foot device needs to be relieved, temporary constraint between an upper rotating disc and a lower rotating disc needs to be relieved, then the stress value of the supporting foot device is measured again, the measured value serves as a final stress value, and stress change data of the bridge structure in the constraint relieving state is obtained by comparing the difference between the initial stress value and the final stress value. The method has the advantages that through accurate stress measurement and scientific calculation analysis, under the condition that traditional balance weight weighing operation is not needed, accurate construction control over the swivel bridge is achieved, and safety and stability of the bridge swivel process are guaranteed.

The invention discloses a ground stress drilling solid rock core confining pressure calibration method, system and equipment and a medium, and relates to the technical field of ground stress measurement. A complete solid rock core is drilled, a resistance strain gauge is pasted on the surface of the rock core, the rock core is put into a confining pressure calibration instrument to apply confining pressure, the resistance strain gauge is used for reading strain data generated in the pressurization process, meanwhile, the confining pressure value is recorded, and the elastic modulus and the Poisson's ratio of the rock core are calculated. According to the method, the elasticity modulus and the Poisson ratio of the solid rock core of the ground stress test drill hole are measured, and more reliable data support is provided for ground stress measurement. And simultaneously. The problem that an experiment cannot be carried out due to the fact that a rock core with a hollow inclusion stressometer is broken and the stressometer is damaged can be effectively solved, the properties of the drilled rock cores at adjacent positions are not changed, the calculated elastic modulus and Poisson's ratio data are the required rock parameters, and the success rate of a ground stress test is effectively improved.

The application provides a kind of port machinery steering bridge absolute stress intelligent detection method and system, it is related to stress measurement and detection technical field, the application is by collecting strain, temperature, steering behavior and load and other multi-source data;The collected data are corrected and characteristic modeling simultaneously, construct absolute stress calculation and intelligent analysis model;Based on operation data screening structure reference operation interval and construct reference stress state, evaluate structure reference stability;On this basis, the absolute stress is decomposed into multiple axes, calculate multi-axis stress decoupling coefficient, realize multi-axis stress safety determination and collaborative control;Further combine stress time evolution characteristics and fatigue accumulation effect, evaluate structure long-term stress evolution risk, and implement steering, load and maintenance strategy when risk is over limit.The application realizes the online perception of steering bridge absolute stress, risk early warning and closed-loop optimization, improves the operation safety and structure reliability of port machinery.

The invention relates to a hot-rolled strip steel residual stress layering detection and quantitative evaluation method, and belongs to the technical field of metal rolling process detection methods. According to the technical scheme of the invention, the method comprises the steps: adding a thickness direction detection level on a required measurement point according to the size specification and the steel grade number of strip steel; acquiring stress actual measurement data of different thickness levels of each detection point through a measurement device; and performing weighted calculation on the multi-layer stress data by adopting a data regression mode to obtain characterization values, and taking the characterization value of each measurement point as a quantitative evaluation parameter of the overall stress state of the strip steel. The method has the advantages that the thickness of the strip steel is measured in a layered mode, weighted averaging is carried out on the measured value and the thickness, the characterization value is obtained, the characterization precision of the stress measurement result of the hot-rolled strip steel is improved, and the method can be more accurately used for evaluating the strip shape of the hot-rolled strip steel.

The invention relates to a stress measurement method. A first transverse wave and a second transverse wave of which incident angles are perpendicular to each other are incident to a to-be-measured material; detecting a first sound time difference when the first transverse wave signal passes through the to-be-detected material under the action of the first tensile force applied to the to-be-detected material or without the action of the tensile force, and detecting a second sound time difference of the second transverse wave signal; calculating a first sound velocity of the first transverse wave signal penetrating through the to-be-tested material under the action of the first tension based on the first sound time difference, and also calculating a second sound velocity of the second transverse wave; and calculating the internal stress of the to-be-measured material under the action of the first pulling force based on the first sound velocity and the second sound velocity, the two ultrasonic transverse waves with the perpendicular propagation directions are incident into the to-be-measured material, the sound velocity square difference is obtained by measuring the sound time difference of the two transverse waves under different stresses, and then the stress is obtained. The calibration process necessary for ultrasonic method measurement of the acoustic elastic effect is omitted, non-calibration metal stress measurement is achieved, and the measurement process is greatly simplified.

The invention discloses an inversion method, particularly discloses an inversion method based on a crustal stress field boundary load, and belongs to the technical field of geological survey processes. The inversion method based on the crustal stress field boundary load is relatively few in technological process and relatively fast in data acquisition. The inversion method is based on a boundary load principle, a stress measurement value array is constructed on the basis of a ground stress value measured on site, a unit boundary force load is applied to a three-dimensional model, a stress value of a measurement point position is calculated, then an overall boundary stiffness matrix is constructed on the basis of the stress value of the measurement point, and the overall boundary stiffness matrix is calculated. And finally solving the linear combination under the boundary condition to enable the stress calculation value at the measuring point position to be equal to the measured value, thereby completing the inversion work of the boundary load of the crustal stress field.

The present invention provides a bridge support column stress measurement method based on structural collaborative force analysis, which belongs to the field of stress measurement technology. It collects stress, strain, and displacement data of each bridge support column in real time; calculates the local stress index of each bridge support column based on the collected real-time data; establishes a structural collaborative force model based on the connection relationship between the overall structural parameters of the bridge and the bridge support columns; calculates the collaborative stress correction index of each bridge support column; compares the collaborative stress correction index with the dynamic stress assessment interval, combines historical data and environmental factors to perform trend analysis, determines whether there is a structural risk, and issues a warning signal when the threshold is exceeded. By introducing a structural collaborative force analysis mechanism, the present invention comprehensively considers the impact of the overall stress state of the bridge on a single bridge support column, can more accurately identify key structural risk points, and improve the reliability and early warning capabilities of bridge safety monitoring.

The invention discloses a contact stress analysis method and system based on a connection component, belonging to the technical field of stress measurement and analysis, and comprising the following steps: obtaining appearance performance parameters of the connection component, analyzing to obtain the shape fitness of the connection component, and comparing with a preset shape fitness threshold to obtain a shape fitness result; executing corresponding shaping control to obtain the shape fitness of an adaptation stress analysis component; dividing the adaptation stress analysis component into a plurality of combined components, obtaining a static stress evaluation index of each combined component, thereby analyzing to obtain a static stress distribution uniformity index of the adaptation stress analysis component; obtaining a static test stress result, thereby obtaining a specified static evaluation influencing factor; obtaining a comprehensive stress evaluation result and outputting it for display, thereby solving the problem of uneven stress distribution caused by the shape fitness of the connection component in the prior art.

The invention relates to the technical field of stress measurement, in particular to a drilling ground stress measuring device based on mechanical radial pressure application, which comprises a device body, a plurality of radial pressure application units arranged along the axial direction of the device body, and a middle column arranged along the axial direction of the device body, the radial pressure applying unit comprises an expansion arm cavity, a plurality of abutting blocks distributed in the circumferential direction of the expansion arm cavity, and a stress detection sensor unit installed in the expansion arm cavity. The multiple expansion arm cavities are connected in series through the negative pressure unit and used for forming negative pressure through the negative pressure unit after measurement is finished, so that the expansion arm cavities retract synchronously. According to the device, the targets of one-time positioning well logging and multi-point synchronous measurement are achieved, the operation efficiency is greatly improved, pressurization is conducted in sequence from bottom to top, independent loading and radial pressure applying of each section are ensured, the expansion arm cavity is controlled to reset rapidly after measurement is completed, the contact force between the device body and the hole wall is effectively reduced, the risks of manual drawing, jamming and equipment damage are reduced, and safety is higher.

The present application proposes a stress inversion and numerical optimization based intrinsic strain field calibration method and system, belonging to the technical field of metal additive manufacturing numerical simulation. The present application solves the problems in the existing strain field calibration method, such as the lack of feedback calibration mechanism based on measured stress, the focus on residual deformation only, the inability to verify the material constitutive model, the poor generalization of intrinsic strain parameters, and the significant deviation between the prediction results of complex components and the actual measurement. The method comprises the following steps: S1: preparing a calibration sample according to the target material; S2: obtaining the measured value of residual stress at the measurement point of the calibration sample; S3: establishing a finite element model of the calibration sample; S4: establishing a target function and performing automatic iterative solution to obtain the optimal solution of the design variable. The system comprises a calibration sample preparation module, a stress measurement module, a modeling module and a design variable solving module.

The utility model relates to the field of buildings, and discloses a structure for preventing large-area pile loading from generating lateral stress on a building foundation, which comprises a pile foundation consisting of a foundation pile and a bearing platform, a loading surface is arranged on the bearing platform, an isolating layer is arranged between the loading surface and the foundation pile, and the isolating layer comprises an isolating cavity. The isolation cavity is internally provided with filler, and lateral stress borne by the building foundation can be reduced through deformation of the filler. Through the arrangement of the isolating layer, the problem of solving stress measurement through the traditional thinking of resisting is converted into the problem of reducing the stress measurement of large-area pile loading on the pile foundation through the thinking of unloading, so that the pile diameter and the pile number are effectively reduced, the engineering amount is reduced, and the economical efficiency is improved.

In one aspect, the present invention relates to a stress measurement technology, and more specifically, to a facial blood flow-based stress measurement apparatus and method that provide a subject's resilience and high-risk group prediction results for stress by analyzing heart rate variability and stress levels based on facial images and psychological stress assessment results through a machine learning-based model.

The invention provides a method for eliminating abnormal values of gear dynamic stress measurement data under a small sample. The method comprises the following steps: step 1, determining gear dynamic stress measurement positions and number requirements; 2, determining the vibration excitation order of the gear dynamic stress measurement data; step 3, classifying and sorting the gear dynamic stress measurement data; step 4, preliminarily screening abnormal data based on a quartile algorithm; 5, determining a statistical characteristic value of the dynamic stress test data; and step 6, finally determining abnormal data based on a Grubbs criterion method. The method can effectively reduce the influence of gross errors on the mean value and standard deviation of small sample data, improve the recognition reliability of abnormal data, and improve the accuracy of gear fatigue risk assessment; the method is rapid and convenient, is easy to program, improves the working efficiency, and facilitates the reduction of manpower and financial costs.

The present invention discloses an in-situ stress measurement device and method for a multi-material interface by laser selective melting, which relates to the technical field of metal additive manufacturing. The in-situ stress measurement device for a multi-material interface by laser selective melting comprises a laser selective melting forming system, a stress and strain measuring device, an embedding system, and a positioning system. During the laser selective melting process, when material A is formed to the position where the stress and strain measuring device is to be embedded, the forming is suspended; the powder at the position to be embedded is first sucked out by a powder suction nozzle according to the coordinate information of the position to be embedded through the positioning system, and then the stress and strain measuring device is sucked out by an electromagnet and placed in the position to be embedded; the forming is continued to embed the stress and strain measuring device; then the multi-material structure can be formed, and in-situ stress and strain measurement of the multi-material interface can be achieved during the forming process of the multi-material structure.