12 results about "Stress measurement" patented technology

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 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 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 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 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.

The invention provides an underwater curtain stress measurement system and method based on a fabric sensor, and the system comprises the fabric sensor which is fixed at a position where the stress of the surface of an underwater curtain needs to be measured, and comprises a microstructure sensing layer and electrodes disposed at the two sides of the microstructure sensing layer; the waterproof assemblies cover the two faces of the fabric sensor respectively and are fixedly connected with the underwater curtain; the data collecting and processing system comprises a data line and a data collector, one end of the data line is connected with the two electrodes of the fabric sensor, and the other end of the data line is connected with the data collector. According to the application, the stress change of different positions of the whole curtain can be monitored in real time, and the influence on water flow is reduced.

This invention belongs to the field of fault instability assessment technology, specifically disclosing a method and system for fault instability assessment based on three-dimensional geostress measurement data. The method includes acquiring the target fault's attitude parameters and nearby shallow three-dimensional geostress measurement data and deep focal mechanism solution data; comparing the shallow three-dimensional geostress measurement data with the deep focal mechanism solution data, selecting shallow three-dimensional geostress measurement data whose stress structure type and maximum principal stress orientation are consistent with the deep data, and removing outlier data to obtain a valid dataset; calculating the shear stress and normal stress on the target fault plane based on the valid dataset and attitude parameters, and using the ratio of shear stress to normal stress as an indicator of fault frictional slip instability risk to determine whether the target fault is in a slip instability risk state. This invention solves the problems of existing fault instability assessment methods based on measured geostress data, such as neglecting the comparison of deep and shallow stress states, ignoring the limitations of two-dimensional data, and improper handling of data discreteness.

The invention discloses an uncalibrated stress measurement method and device based on horizontal shear waves and incremental deformation, and relates to the technical field of ultrasonic nondestructive testing, and the method comprises the steps: obtaining an ultrasonic horizontal shear wave excitation signal and an ultrasonic horizontal shear wave time domain signal; according to the ultrasonic horizontal shear wave excitation signal and the ultrasonic horizontal shear wave time domain signal, determining the propagation time of the ultrasonic horizontal shear wave in the test piece to be detected; according to the propagation time and the distance between the excitation point and the receiving point, determining the propagation speed of the ultrasonic horizontal shear wave in the test piece to be detected; and determining a stress value on a detection path from the excitation point to the receiving point of the test piece to be detected according to the propagation velocity. The method can avoid the measurement problem of the high-order elastic constant of the material, avoids the dependence of a stress measurement result on a calibration result, and effectively improves the accuracy of stress measurement.