89 results about "Stiffness coefficient" patented technology

The application discloses a kind of centrifugal pump shafting critical speed calculation method, including the finite element calculation of radial roller bearing and thrust roller bearing stiffness coefficient curve, the prestressed modal analysis and critical speed calculation of centrifugal pump shafting considering different bearing stiffness coefficient.The setting of constraint condition of this method is in line with actual situation, which can realize the accurate calculation of centrifugal pump shafting critical speed, and help to improve the reliability of safety check of centrifugal pump shafting in design stage, at the same time, the calculation steps are simple, and the engineering application range is wide.

The invention relates to the technical field of composite material structure dynamics analysis, and provides a method and system for predicting the inherent frequency of a three-phase functionally graded composite material conical plate, and the method comprises the steps: employing an improved Halpin-Tsai model to calculate the equivalent parameters of a GPL-containing two-phase composite matrix, solving the equivalent parameters of a three-phase composite layer, and calculating the inherent frequency of the three-phase composite material conical plate. The method comprises the following steps: constructing a nonlinear geometrical relationship between a displacement field and a strain field, calculating a stiffness coefficient of each layer, constructing kinetic energy of the three-phase composite material conical plate, calculating an energy coefficient according to the stiffness coefficient of each layer, constructing potential energy of the conical plate according to the energy coefficient, and constructing a modal displacement function by adopting a Chebyshev polynomial and a boundary function. And establishing a characteristic equation based on a minimum potential energy principle and solving to obtain the inherent frequency of the three-phase composite material conical plate. According to the method, efficient calculation of the inherent frequency of the three-phase composite material conical plate is achieved, and the reliability and engineering application value of structural dynamics analysis are remarkably improved.

The invention discloses a foundation pit supporting structure deformation and internal force calculation method. In the calculation method, an out-pit constraint stiffness matrix is introduced as a calculation factor, and a stiffness coefficient is iteratively calculated; the calculation method comprises the following steps: S1, constructing a foundation pit supporting structure calculation model; s2, a displacement-load total balance equation of the supporting structure under the undetermined supporting working condition of the foundation pit is determined; s3, a servo support is installed, prestress is loaded, a constraint stiffness matrix is introduced, a stiffness coefficient is calculated in an iterative mode, a displacement-load total balance equation of the supporting structure is established step by step, and the deformation condition of the supporting structure is analyzed and calculated; s4-5, the steps S2 to S3 are repeated until installation of all servo supports and prestress loading are completed, and displacement and internal force of the supporting structure are calculated; and S6, the foundation pit continues to be excavated to the pit bottom, deformation and internal force under all working conditions are calculated, and regulation and control calculation can be conducted in the process. By means of the calculation method, accurate calculation of deformation and internal force of the foundation pit supporting structure under the servo supporting effect can be achieved.

The invention discloses an equivalent pile length calculation method for long and short piles of a foundation pit based on a non-limit state, and relates to the field of equivalent pile length calculation, the equivalent pile length calculation method for the long and short piles of the foundation pit based on the non-limit state comprises the following steps: S1, acquiring parameters, and presetting a standard, principle and scheme set; s2, matching the long parameter with the scheme set, and arranging a displacement meter and a strain meter; s3, collecting data through a displacement meter and a strain meter, and forming effective mechanical response data; s4, establishing a stiffness load displacement equivalent length calculation model; s5, the rigidity coefficient and the load sharing proportion are calculated, and an equivalent pile length initial value is obtained through reverse deduction; and S6, the equivalent pile length initial value is adjusted, and a foundation pit long and short pile equivalent pile length calculation report is generated. According to the method, engineering suitability calculation of the equivalent pile length in a non-limit state is achieved through a non-limit state guided double-equivalent logic driven equivalent pile length calculation system for the long and short piles of the foundation pit, and the one-sided core pain point of single equivalent logic is avoided.

The invention discloses an active vibration absorber control strategy for vibration at the tail end of a flexible arm, and relates to the technical field of mechanical arm control, and the active vibration absorber control strategy comprises the following steps: building a three-dimensional model for a two-degree-of-freedom flexible mechanical arm, describing the joint flexibility of a system by using a linear spring, and representing the rigidity coefficient of a flexible joint by using the elastic coefficient of the linear spring; fuzzy RBF adaptive PID control is trained in combination with a real object, the identification precision of the model is improved, and vibration suppression is realized; in the fuzzy control, input variables are fuzzified by simulating the thinking mode of human beings, reasoning is carried out in combination with expert experience rules, and finally a system of an accurate dynamic model is established. According to the control strategy, the limitation of a traditional control technology based on a model during control is reduced, dynamic hysteresis nonlinearity generated in actual work is effectively corrected, the control precision is improved, fuzzy rule parameters are adjusted through modal analysis in combination with system characteristics, and the control precision is improved. Therefore, the vibration suppression force synthesis in different scenes is more accurate, and the vibration suppression effect is better.

The present application belongs to the field of mechanics, and particularly relates to a method for eliminating error of a quasi-static compression mechanics experiment system. By using a constant pressure or a constant loading speed of a pressure head on a testing machine to perform quasi-static uniaxial compression on a test piece at room temperature, and taking two test pieces of different heights, the relationship between the system stiffness, the force and deformation of the system pressure head can be obtained, so as to obtain two corresponding force-time curves and displacement-time curves. By combining the two equations and eliminating the unknown Young's modulus E, the stiffness coefficient of the test system can be obtained, and the displacement-time curve of the pressure head can be obtained. Subsequently, the Young's modulus E can be inversely solved. The present application corrects the error of the mechanics experiment by defining the system stiffness coefficient, so as to realize a higher precision of the Young's modulus E and improve the accuracy of the quasi-static mechanics experiment.

The present disclosure provides a Timoshenko beam model equivalent method and system of a corrugated steel plate support structure, and relates to the technical field of stress analysis of a corrugated steel plate support structure, comprising: solving the stiffness coefficients of the corrugated steel plate in a local coordinate system, including tensile stiffness, bending stiffness and shear stiffness; solving the equivalent stiffness coefficients of the orthotropic corrugated steel plate in a global coordinate system, including equivalent tensile stiffness, equivalent bending stiffness and equivalent shear stiffness; solving the equivalent section bending stiffness of the corrugated steel support structure; solving the equivalent section shear stiffness of the corrugated steel support structure; and equivalent the corrugated steel support structure to a Timoshenko beam model. The present disclosure can realize the rapid equivalent of the corrugated steel plate support structure to a Timoshenko beam model.

The application provides a method for determining the longitudinal wave velocity after fluid replacement in an anisotropic medium and related equipment. The method comprises the following steps: determining an average bulk modulus based on a matrix bulk modulus; determining a first bulk modulus when the medium contains fluid based on first property data; determining a second bulk modulus when the medium does not contain fluid based on the first property data, the matrix bulk modulus, the average bulk modulus and the first bulk modulus; determining a second vertical stiffness coefficient when the medium does not contain fluid based on the first property data, the average bulk modulus, the first bulk modulus and the second bulk modulus; obtaining second property data of each predetermined replacement fluid; and determining the longitudinal wave velocity after the fluid in the medium is replaced by the predetermined replacement fluid based on the first property data, the average bulk modulus, the second bulk modulus, the second vertical stiffness coefficient and the second property data. The technical problem that the longitudinal wave velocity determined after fluid replacement in an anisotropic medium is not accurate in the prior art is solved.

The invention relates to a horizontal rotation vibration suppression method for a wind turbine blade hoisting system. The method comprises the following steps: acquiring basic parameters of a blade hoisting system; the inherent frequency of horizontal rotation of the main structure is obtained; at least two tuned mass dampers are arranged on the blade hoisting system to form the blade hoisting system with multiple tuned mass dampers; calculating a dynamic matrix equation of the blade hoisting system provided with the multi-tuned mass damper; calculating a response equation of horizontal rotation of the main structure; and calculating parameters of each tuned mass damper according to the response equation, and optimizing the parameters to obtain the vibration suppression blade hoisting system with the tuned mass damper with the optimal parameters. According to the method, the parameters of the mass damper are optimized by considering the installation position and the parameters of the mass damper and the response equation of horizontal rotation of the main structure, the optimal rigidity coefficient and the optimal damping coefficient are obtained, and therefore the optimized multi-tuned mass damper system is obtained, and the vibration suppression effect is better.

The application relates to the technical field of aero-engine structural design, in particular to a dynamic modeling method of a non-uniformly pre-tightened circular-arc end-tooth connected rotor, which comprises the following steps: establishing a whole-circle three-dimensional model and a finite element simulation model of a short bolt connected circular-arc end-tooth structure, setting a contact interface and a boundary condition, applying a working load, applying a circumferential non-uniform pre-tightening force to the bolt, calculating the stiffness of the end-tooth structure, establishing a beam element dynamic model of a convex-tooth side rotor and a concave-tooth side rotor, superimposing the local connection stiffness of the end-tooth structure and the rotor element stiffness, and assembling a whole dynamic model of the rotor system. The application can consider the actual situation of circumferential non-uniform relaxation of the circular-arc end-tooth pre-tightening force, multiple bolt assemblies can apply circumferential non-uniform pre-tightening force, only the connection stiffness coefficient of the end-tooth structure needs to be calculated, and the mass and rotational inertia characteristics of the end-tooth structure and the rotor non-continuous structure characteristics can be more accurately simulated.

This invention discloses a robust design method for technical parameters of passive suspension systems aimed at performance optimization. It can robustly design two types of suspension system parameters—stiffness coefficient and damping coefficient—to cope with changes in vehicle weight. Specifically, the method constructs a four-wheel vehicle passive suspension system model and uses an improved Harris-Eagle optimization algorithm to search for the suspension stiffness coefficient and damping coefficient under varying vehicle weight conditions, thereby ensuring a balanced balance between vehicle ride smoothness and handling stability. This invention is a technical parameter design method for four-wheel vehicle passive suspension systems that does not rely on trial and error by technicians to optimize the technical parameters of the passive suspension system. More importantly, this invention considers the uncertainty of vehicle weight during actual driving; the designed parameters are optimal under different vehicle weight variations, exhibiting a high degree of robustness.

The application belongs to the technical field of foundation horizontal bearing capacity calculation, and specifically discloses a kind of offshore wind power foundation horizontal bearing capacity accurate calculation method, the method comprises: integrating wave spectrum, wind condition, tide and soil parameters to form multidimensional data set;Three-dimensional pile soil model is constructed and wave force and wind load are coupled;Stiffness coefficient is calculated and combined with length-diameter ratio to identify pile type;According to the type of pile, the environmental deviation compensation coefficient is quantified;After calculating the preliminary horizontal bearing capacity, the bearing capacity failure critical state is judged based on real-time displacement monitoring data, if the critical state is reached, the preliminary bearing capacity is modified by linear weighting of displacement deviation compensation coefficient and environmental deviation compensation coefficient.The application dynamically couples time-varying environmental load, simulates the interaction between pile and soil in detail, establishes a stiffness self-adaptive grading mechanism and a double compensation feedback system, significantly improving the accuracy and real-time warning capability of horizontal bearing capacity calculation in complex marine environment.

The present application relates to gear machining technical field, especially a kind of variable tooth thickness modification machining method for double lead worm gear and worm, including the wave form distortion rate of idle cutting force of hobbing cutter and torsional stiffness coefficient;Real-time monitoring cutting force wave form distortion rate and tool torsional deformation, calculate disturbance intensity index to divide disturbance level and set detection opportunity;Through the tooth thickness curve of actual measurement, tooth thickness change rate coefficient is obtained to judge machining quality;The tooth thickness deviation curve of unqualified tooth groove is analyzed to determine the dominant interference type, and the spindle speed or tool pose is regulated based on disturbance level;The control effect is verified by attenuation coefficient;When not up to standard, attenuation difference is used to optimize control coefficient;Finally, the overall quality of worm is evaluated by the consistency coefficient of tooth thickness change rate of each tooth groove of full tooth surface.The present application solves the problem that the full tooth surface consistency of formed worm is low due to the resonance and deformation disturbance of asymmetric characteristics of hobbing cutter in variable tooth thickness worm machining.

The invention discloses a design method of a vibration transmission sheet of thin kidney-shaped connecting ribs, which comprises the following conditions: 1, a vibration transmission sheet body is arranged, and the vibration transmission sheet body comprises one or more groups of thin kidney-shaped connecting ribs; and 2, the value of the ratio of the width wend of the two ends of the thin kidney-shaped connecting rib to the width wmiddle of the middle section of the connecting rib is as follows: by adopting the design of the vibration transmission sheet of the thin kidney-shaped connecting rib, the problems in two aspects can be solved at the same time: 1, the problem that the service life of the vibration transmission sheet is influenced due to non-uniform distribution of internal stress in the connecting rib is solved; and secondly, the equivalent average width of the connecting rib is reduced, so that the stiffness coefficient of the vibration transmission sheet is reduced, the resonant frequency of the vibrator is reduced, and the low-frequency performance of the bone conduction earphone and the tactile feedback actuator is improved.

The invention relates to an anti-deformation leveling algorithm based on a foot-ground contact model and a platform rigidity model. The anti-deformation leveling algorithm comprises the steps that a foot-ground interaction load-settlement model, a platform load-deformation rigidity model and a leveling algorithm with feed-forward compensation are established; a foot-ground interaction load-settlement model is adopted to describe foot-ground contact settlement behaviors, and the landing leg settlement amount is predicted by identifying ground rigidity parameters; secondly, establishing a platform structure stiffness matrix, quantifying a platform load-deformation relationship, performing simulation calculation on a platform system under a typical leveling pose by using a finite element method, and obtaining stiffness coefficient matrixes corresponding to different poses; and finally, designing a leveling algorithm with feed-forward compensation, and superposing the total compensation amount to leveling control output by predicting the landing leg settlement amount and the landing leg structure deformation amount so as to realize feed-forward control. According to the method, the foot-ground contact model and the platform load-deformation rigidity model are constructed, and rapid and stable leveling is realized through a dual-mode control algorithm.

The application discloses a parameter identification device and method based on a Lugre friction model. The method comprises the following steps: creating a PID closed-loop control system configured with the Lugre friction model, drawing a first characteristic curve of output rotating speed w and friction torque F fric ; identifying Coulomb friction and stribeck speed of the friction torque F fric according to the first characteristic curve; obtaining a peak voltage Umax input by a servo motor; inputting a speed extremely slowly changing identification voltage to the servo motor, the identification voltage rising from an initial voltage to the peak voltage Umax at first and then falling from the peak voltage Umax to a negative peak voltage Umax; obtaining a displacement S between the servo motor and a controlled object, and drawing a second characteristic curve of the displacement S and the identification voltage; identifying bristle stiffness coefficient σ0 according to the second characteristic curve; creating a current loop of the servo motor in the PID closed-loop control system; drawing a third characteristic curve of displacement response of the servo motor; and identifying bristle damping coefficient σ1 according to the third characteristic curve.

The invention relates to the technical field of micro-force measurement and calibration, and discloses a friction sensor traceable calibration method based on electrostatic force and flexible dangling, and the method comprises the steps: obtaining the dangling rigidity coefficient of parallel opposite-side flexible dangling and the capacitance gradient of a cylindrical capacitor matrix, and analyzing the response relation between the voltage square and the displacement. Determining the minimum effective loading voltage of the contact between the suspension and the sensor so as to establish a calibration zero point; the stiffness coefficient of the sensor to be calibrated is calculated on line, finally, a series of target force voltages are calculated and applied based on the obtained parameters, a series of traceable target forces are generated on the sensor, and calibration is completed. According to the method, the initial force error is eliminated by establishing the real calibration zero point, the direction purity of the loading force is ensured by utilizing the motion characteristic of the flexible dangling, the force value is traced to the basic quantity of the international unit system, and the calibration accuracy and reliability of the friction sensor are improved.

This invention relates to a method for identifying the elastic modulus and loss factor of functionally graded coatings under thermal conditions based on vibration testing. It belongs to the field of structural vibration and material parameter identification technology, and includes: preparing a metal plate specimen coated with a functionally graded coating, and obtaining structural geometric parameters, component material parameters, and thermal vibration environment parameters; applying vibration excitation to the metal plate specimen under thermal conditions to obtain the test natural frequency and test damping ratio of the target order; establishing an equivalent material parameter model of the functionally graded coating to obtain the equivalent Young's modulus, shear modulus, Poisson's ratio, and density of the coating material, and calculating the transformation stiffness coefficient; establishing an analytical dynamic model of the metal plate specimen under thermal conditions based on first-order shear deformation theory and thermoplastic theory to obtain the theoretical natural frequency and theoretical damping ratio of the corresponding order; constructing an error function constrained by the natural frequency and resonance response, and obtaining the equivalent elastic modulus and loss factor of the functionally graded coating through iterative optimization based on a particle swarm optimization algorithm.

This invention discloses a semi-analytical method and system for calculating the stiffness and damping coefficients of foil gas dynamic bearings, relating to the field of air conditioning and clothing temperature control technology. It aims to address the shortcomings of traditional Reynolds equation methods in terms of accuracy and universality, as well as the low computational efficiency and mesh distortion issues of existing CFD methods. The method includes: constructing a fluid-structure interaction (FSI) computational model to calculate and obtain the static equilibrium position of the journal; applying an eccentricity perturbation at the static equilibrium position and performing an additional steady-state FSI calculation to obtain the four stiffness coefficients of the foil bearing using a first set of analytical formulas; applying small-amplitude simple harmonic vibrations along the x and y directions to the journal and performing two transient FSI calculations to obtain the four damping coefficients of the foil bearing using a second set of analytical formulas. This invention combines high accuracy and high computational efficiency, providing an efficient and reliable analytical tool for evaluating the dynamic characteristics of foil bearings and designing the stability of the rotor systems they support.

The invention relates to the technical field of force sensor calibration, in particular to a force application device for force sensor calibration. Comprising a force transmission sleeve connected with a force sensor; the first spring and the second spring are arranged in the force transmission sleeve in the axis direction and used for generating spring force; the force application rod is used for compressing the first spring or the second spring; the driving mechanism drives the force applying rod to do reciprocating linear motion; and the displacement measurement assembly is used for measuring the moving distance of the force application rod. The force application rod is driven by the driving mechanism to do reciprocating rectilinear motion, so that the force application rod compresses the spring, automatic loading is achieved, continuous force in the positive direction and the negative direction is achieved at the same time, impact generated during force application can be effectively avoided, and the effect of protecting the force sensor is achieved; the moving distance of the force application rod is measured through the stiffness coefficient of the spring and the displacement measuring assembly, the magnitude of the pushing force or the pulling force borne by the force transmission sleeve is calculated, then the force acting on the force sensor is known, and the accuracy of the loading force value is guaranteed.

The invention discloses a bolt pretightening force precise control tool and method based on direct deformation measurement, and belongs to the technical field of mechanical assembly and precise measurement, and the tool comprises an elastic force measuring ring which sleeves a bolt and is located between a baffle and a main nut, the upper and lower end faces of the elastic force measuring ring are parallel reference surfaces, and the elastic force measuring ring has a preset rigidity coefficient k; the deformation measuring mechanism is installed on the elastic force measuring ring through a fixing frame, a measuring head of the deformation measuring mechanism makes contact with the measuring plane of the elastic force measuring ring, and the deformation measuring mechanism is used for measuring the compression deformation quantity delta L of the elastic force measuring ring in real time; and the locking nut is screwed on the bolt, is positioned between the elastic force measuring ring and the baffle plate, and is used for bearing and locking the tension of the bolt after the pre-tightening force reaches a target value, so that the elastic force measuring ring is unloaded. Through simple combination of the elastic force measuring ring and the dial indicator, direct measurement and real-time monitoring of the pre-tightening force can be realized, and while the control precision of the pre-tightening force is improved, the equipment cost and the operation complexity are reduced.

This invention provides a damping vibration reduction device and configuration method for wind turbine blades. The device includes a force transmission component and an energy dissipation damping unit. The force transmission component includes two pre-tensioned force transmission damping cables, and the energy dissipation damping unit includes an eddy current energy dissipation component, an elastic energy dissipation component, and a force transmission frame. The method includes establishing a numerical model of the wind turbine blade-force transmission damping cable and applying an external wind load to the blade; constructing a multi-objective optimization function and setting the value ranges of the spring stiffness coefficient and damping coefficient as constraints; using the PSO method to solve for the optimal spring stiffness coefficient and optimal damping coefficient of the damping vibration reduction device. During the solution process, a set of spring stiffness coefficients and damping coefficients are used as particles, and the fitness of the particles is calculated based on the numerical model of the wind turbine blade-force transmission damping cable and the constructed multi-objective optimization function. This invention has the advantages of wide-band, high-efficiency vibration reduction and high overall reliability.

The present application relates to numerical control bending processing technical field, disclose a kind of copper bar bending springback amount control method, including obtaining effective displacement sequence and effective force sequence, calculate first derivative sequence, extract the data mean in sliding variance steady state interval as system equivalent stiffness coefficient;Second derivative sequence is calculated, and the attenuation proportion of first derivative sequence is combined with negative jump phenomenon and macroscopic yield of material is judged, and dynamic yield displacement and dynamic yield force are latched;Control machine tool enters open loop pressure state to collect stress relaxation force drop value and springback displacement drift, calculate machine tool transient structure stiffness, combine system equivalent stiffness coefficient to extract workpiece real material stiffness and calculate stress relaxation rate.The present application calculates the first derivative sequence and second derivative sequence of effective force sequence to effective displacement sequence, to provide high-precision dynamic yield displacement and dynamic yield force basic data for subsequent springback calculation.

This invention discloses a method for determining the mechanical performance parameters of buckling-restrained braces based on experimental data, within the field of building energy dissipation and vibration reduction technology. The method includes: calculating the elastic stiffness using linear equation fitting based on the unloading law of the hysteresis curve of the buckling-restrained brace test; calculating the post-yield stiffness of the buckling-restrained brace using linear equation fitting based on the maximum load data points on the hysteresis curve under various loading levels, thereby calculating the post-yield stiffness coefficient of the buckling-restrained brace; plotting the elastic stiffness curve through the origin on the hysteresis curve and intersecting it with the post-yield stiffness curve, solving for the coordinates of the intersection point, and thus determining the yield bearing capacity and yield displacement of the tested buckling-restrained brace. This invention can accurately determine the values ​​of various mechanical performance parameters based on the experimental data of the buckling-restrained brace, thereby quickly and accurately determining whether the buckling-restrained brace is a qualified product.

The invention provides a flight operation robot contact force tracking control method based on variable stiffness admittance. The method comprises the following steps: S1, establishing a dynamic model of a flight operation robot system; s2, designing a self-adaptive variable stiffness admittance model, generating an expected reference trajectory by dynamically adjusting a stiffness coefficient, and compensating the influence of unknown environmental parameters; s3, designing a nonlinear disturbance observer to estimate system disturbance, and providing disturbance compensation for the pose controller; s4, a pose controller is designed based on the obstacle Lyapunov function, reference trajectory tracking is achieved, and the position error is strictly restrained to be within a safe range; s5, the rotating speed of each rotor wing of the flying operation robot is calculated through control input; the flying operation robot is controlled to realize stable contact force tracking; according to the method, uncertainty and contact disturbance in an unknown dynamic environment can be effectively dealt with, and the contact force tracking precision and the operation safety of the flying operation robot are improved.

The invention provides a spring stiffness coefficient detection device, which belongs to the technical field of spring elasticity detection, and structurally mainly comprises an upper pulling part and a lower pulling part which are respectively used for pulling two ends of a spring and are opposite to each other up and down, and a state monitoring part used for detecting whether the spring is in a vertical state when being stretched, the upper pulling part can move vertically, and the lower pulling part can move vertically. The pull-down part cannot vertically move, the pull-up part is provided with a tension sensor for detecting the magnitude of tension applied to the spring, and after the pull-down part is connected with the bottom end of the spring, the pull-up part vertically moves downwards to be connected with the top end of the spring and then vertically moves upwards by a set distance, so that the spring is stretched to a set length. The spring stiffness coefficient detection device is high in detection efficiency and accurate in detection result.

The application provides a mechanical manufacturing feed automatic control system and method, and belongs to the technical field of automatic control. Real-time process parameters of a rolling slab to be entered into a finishing mill stand are acquired. Multiple rolling force change trends of the rolling slab along the length direction are determined according to the real-time process parameters. Multiple rolling mill stiffness coefficients of the finishing mill set are determined. The first roll gap compensation sequence caused by the rolling force change is obtained by feeding forward mapping of the roll gap effective profile change and the thickness change based on all the rolling mill stiffness coefficients and all the rolling force change trends. The second roll gap compensation sequence is determined according to the actual thickness value and the target thickness value. The dynamic adjustment instruction of the working roll gap of the finishing mill set is determined according to the first roll gap compensation sequence and the second roll gap compensation sequence, and the rolling plate thickness is controlled based on the dynamic adjustment instruction. The scheme of the application can control the rolling plate thickness under the conditions of rolling force fluctuation and process parameter change at different positions of the rolling plate.

The invention provides a Timoshenko beam model equivalent method and system of a corrugated steel plate supporting structure, and relates to the technical field of corrugated steel plate supporting structure stress analysis, and the method comprises the steps: solving rigidity coefficients of a corrugated steel plate under a local coordinate system, including tensile rigidity, bending rigidity and shearing rigidity; solving equivalent stiffness coefficients of the orthotropic corrugated steel plate under the global coordinate system, wherein the equivalent stiffness coefficients comprise equivalent tensile stiffness, equivalent bending stiffness and equivalent shearing stiffness; the equivalent section flexural rigidity of the corrugated steel supporting structure is solved; the equivalent section shear stiffness of the corrugated steel supporting structure is solved; and enabling the corrugated steel supporting structure to be equivalent to a Timoshenko beam model. According to the method, the corrugated steel plate supporting structure can be quickly equivalent to the Timoshenko beam model.

The invention relates to an apparatus for the two-way isolation of products stored on racks, independent of the load weight and independent of the load position on the racks, which comprises: a frame; a first subframe; a second subframe, wherein first friction reducing means are positioned between the first and second subframes; first elastic means that operatively connect each subframe; and a third subframe slidingly connected to the second subframe by means of a plurality of second friction reducing means, wherein a plurality of second elastic means operatively connect the second subframe to the third subframe, wherein each of the elastic means has a different rigidity coefficient, wherein the elastic means with a lower rigidity coefficient.