Patents
Literature
Patsnap Eureka AI that helps you search prior art, draft patents, and assess FTO risks, powered by patent and scientific literature data.

107 results about "Equivalent stiffness" patented technology

The equivalent stiffness for the beam is the ratio of the applied load to the deflection at the point of application of the load. The equivalent spring constants for beams with various other types of loading and/or boundary conditions can be obtained in a similar manner. Some of the more commonly encountered cases...

Ground resonance test suspension device and test method

The invention relates to the technical field of vibration tests, in particular to a ground resonance test suspension device and a test method. The ground resonance test suspension device is provided with a bearing frame body, a hoisting mechanism, a bearing mechanism and a suspension mechanism, the bearing frame body is composed of a bearing supporting column, a cross beam and a longitudinal beam, and the position of the cross beam can be adjusted; a bracket of the bearing mechanism is provided with a bottom beam, an auxiliary supporting beam and a supporting beam, and a flexible air cushion is arranged on the supporting beam. A flexible supporting unit of the suspension mechanism is provided with a main spring rope, an upper hanging scaffold, a lower hanging scaffold and an auxiliary spring rope, and an auxiliary spring rope connecting unit can control the state of the flexible supporting unit. The invention further provides a ground resonance test method which comprises the steps of suspension pretreatment, aircraft suspension and test, and the equivalent stiffness of the suspension mechanism can be adjusted. The aircraft suspension system can adapt to different aircraft sizes and weight distribution, and the equivalent stiffness of the whole suspension system can be adjusted to meet the test support frequency requirement.
Owner:BAI JING HANG XIAN (CHANG ZHOU) KE JI YOU XIAN GONG SI

Side direct-plugging wiring terminal block structure and elastic sheet simulation design method

The invention discloses a side face direct-insertion wiring terminal block structure and an elastic piece simulation design method of the side face direct-insertion wiring terminal block structure. Comprising an insulating shell, a conducting strip, a first elastic piece, a second elastic piece and a push block abutting against the elastic pieces, a wire can be inserted along the side face and clamped by a wire clamping block, and electricity conduction and disengagement prevention are achieved; the elastic piece is made of a metal material with resilience, and the elastic piece is bent to form a mounting part and a camber beam structure so as to provide stable clamping force. In order to optimize the performance of the elastic sheet, a simulation design method is adopted to establish an elastic sheet finite element model, set material attributes and constraint and loading conditions, carry out mesh refinement on a bending area and a wire clamping opening, start large deformation analysis and draw a force-displacement curve, so that the equivalent stiffness, the maximum stress and the deformation of the elastic sheet are obtained. Through simulation comparison of different design schemes, the optimal structure meeting the strength and resilience requirements can be determined. According to the invention, the stable conduction of the side plugging terminal and the predictable design of the performance of the elastic sheet are realized, and the assembly reliability and the design efficiency are improved.
Owner:CHENGDU RELIANCE ELECTRIC

Numerical simulation analysis method for near-river ultra-deep foundation pit under action of seepage flow

The invention discloses a numerical simulation analysis method for a near-river ultra-deep foundation pit under the action of seepage flow, and the method comprises the following steps: S1, constructing a three-dimensional numerical model based on finite element software PLAXIS 3D, and constructing a non-uniform stratum model in combination with a Borehole module; s2, fine modeling is conducted through the underground diaphragm wall, the reinforced concrete supports and the latticed columns; s3, simulating a small strain hardening characteristic and a rigidity attenuation effect of the soil body by adopting an HSS model; s4, simulating underground water flow by combining plastic steady-state seepage analysis, and simplifying the three-axis cement mixing pile into an underground diaphragm wall structure through an equivalent stiffness principle; and S5, step-by-step excavation and support sequential control construction procedures are adopted, and finally, the reliability of the model is verified by comparing a horizontal displacement simulation result of the diaphragm wall with field monitoring data. According to the method, the foundation pit deformation rule is predicted through HSS constitutive model and seepage coupling analysis, and the foundation pit deformation prediction precision is remarkably improved.
Owner:WENZHOU OUJIANG WATER DIVERSION DEV CO LTD +1

Frame structure design method based on rigidity reduction

The invention discloses a frame structure design method based on rigidity reduction. The method comprises the following steps that 1, rod end bending moments Mb and Mc and axial force Nc of frame beams and columns are obtained through calculation; step 2, obtaining actual reinforcement areas Asb0 and Asc0, section sizes and concrete strength of frame beams and columns; 3, the equivalent stiffness Kb1 of the frame beam is obtained through calculation according to the formula Kb1 = Mb0.75y / phi b0.75y; 4, the equivalent stiffness Kc1 of the frame column is obtained through calculation according to the formula Kc1 = Mc0.75y / phi c0.75y; 5, comparing the equivalent stiffness of the frame beam and the frame column with the initial flexural stiffness, and ending after the deviation is less than or equal to 15%; 6, calculating a shear force design value of the frame beam, calculating stirrups needing to be configured for the frame beam, and rechecking a shear-resistant section; and 7, calculating a shear force design value of the frame column, calculating stirrups needing to be configured for the frame column, and rechecking a shear-resistant section. Compared with the prior art, an overall calculation model of the frame structure is established, the real rigidity of a structural member is obtained through multiple iterations, section reinforcement is optimized, and the reinforcement amount is reduced; and the overall anti-seismic performance is improved.
Owner:HONG KONG HUAYI DESIGN CONSULTANT (SHENZHEN) CO LTD

Viscoelastic boundary verification method, device and equipment based on isoparametric elements and medium

The invention discloses a viscoelastic boundary verification method, device and equipment based on isoparametric elements and a medium, and the method comprises the steps: building a three-dimensional geometric model of a target structure according to geometric dimensions and material attributes, discretizing the three-dimensional geometric model into initial three-dimensional subunits, and then building an initial finite element mesh model; after identifying a target boundary surface to be applied with an artificial viscoelastic boundary, assigning boundary parameters to obtain each three-dimensional subunit and form a finite element model; all the three-dimensional subunits are mapped to a standard unit through equal-parameter coordinate transformation, an equivalent stiffness coefficient matrix and an equivalent damping coefficient matrix are obtained through calculation and then stacked and assembled, and an overall stiffness matrix and an overall damping matrix are formed; and calculating displacement response data based on the overall stiffness matrix and the overall damping matrix. According to the embodiment of the invention, by introducing the isoparametric coordinate transformation, the irregular boundary form can be directly processed without introducing an additional boundary unit, and the calculation requirement of an actual complex engineering model is met.
Owner:BEIJING GLORY PKPM TECH CO LTD

Conical floating sleeve drill bearing analysis method based on cloud computing

The invention belongs to the field of industrial control, particularly relates to a cone floating sleeve drill bit bearing analysis method based on cloud computing, and aims to solve the problem that systematic errors are generated in fault diagnosis due to the fact that the actual working condition influence is ignored in the related technology. The method comprises the following steps: acquiring a bearing vibration signal; working parameters are determined, signal decomposition operation is executed according to the working parameters, and bearing characteristic components are obtained; according to the bearing characteristic component and the environmental parameters, determining an equivalent stiffness tensor of the cone floating sleeve drill bit bearing working under a preset working condition, and according to the equivalent stiffness tensor, solving a bearing system dynamic model to obtain evolution field data; determining a target feature vector according to the bearing feature component and the evolution field data, and mapping the target feature vector to a preset fault feature space; and determining the distance between the target feature vector and the plurality of typical fault feature vectors, and determining a bearing control strategy of the cone floating sleeve drill bit according to the distance. When the method is applied to bearing analysis, the accuracy is higher.
Owner:QIANJIANG JIANGHAN DRILLING TOOLS CO LTD

U-shaped steel-encased-concrete composite beam and simulation calculation method

The invention relates to the technical field of simulation calculation, in particular to a simulation calculation method of a U-shaped steel-encased-concrete composite beam, which comprises the following steps: S1, establishing a two-parameter interface equivalent stiffness model of the U-shaped steel-encased-concrete composite beam with a rear anchor bolt; s2, solution and response extraction; s3, calculating a slip residual error and interface energy, and judging whether a target slip feature is met or not according to a double-convergence criterion; if the convergence requirement is not met, adaptively updating the interface parameters and returning to S2 for repeated solution, and if the convergence criterion is met, applying the converged interface rigidity parameters to design feedback of pretightening force selection of the rear anchor bolts and anchor bolt spacing and node construction of the rear anchor bolts. According to the method, the two-parameter interface equivalent stiffness model and the adaptive algorithm based on the slip residual error enable the interface normal stiffness and the interface tangential stiffness to be automatically converged to the target slip characteristic, manual parameter adjustment is avoided, the simulation stability and the calculation precision are improved, and integration of composite beam structure design and simulation analysis is achieved.
Owner:SICHUAN PROVINCIAL ARCHITECTURAL DESIGN & RES INST

Mechanical modeling method for thin shell of densely-distributed pre-supporting structure

The invention provides a dense pre-support structure thin shell mechanical modeling method, and relates to the technical field of tunnel engineering soft stratum pre-support structure mechanical modeling, and the method comprises the steps: calculating the equivalent stiffness of a pipe shed-jet grouting pile composite layer based on a Voigt theory; establishing a continuous thin shell model taking the control equation as a core; constructing a plastic / elastic disturbance partition in front of the tunnel face and a four-section type boundary condition of a supporting structure through a Pasternak foundation model; and solving the constructed continuous thin shell mechanical model through a finite difference method to obtain radial displacement, and completing mechanical modeling of the tunnel engineering soft stratum pre-supporting structure. The continuous thin shell model designed by the invention can provide high-reliability theoretical support for tunnel pre-support design.
Owner:CHINA UNIV OF GEOSCIENCES (WUHAN)

Electrostatic tuning optimization method and device for metal resonator gyroscope

The invention discloses an electrostatic tuning optimization method and device for a metal resonator gyroscope. The method comprises the following steps: establishing a dynamic model based on structural symmetry disturbance and a coupling stiffness effect; based on the dynamic model, calculating modal frequency distribution of the metal resonator gyroscope under different azimuth angles to obtain modal frequency difference data, and based on the modal frequency difference data, constructing an equivalent stiffness distribution model, and quantifying stiffness nonuniformity of the resonant structure to obtain a stiffness matrix; based on the stiffness matrix, voltage control parameters corresponding to the azimuth angles are obtained, the voltage control parameters are applied to the multiple electrostatic tuning electrodes, and an optimized stiffness matrix is obtained; and recalculating the modal frequency of the metal harmonic oscillator based on the optimized stiffness matrix. The invention solves the technical problem that the prior art is mainly suitable for the inertial device before or after packaging but is difficult to effectively eliminate the frequency cracking after packaging.
Owner:BEIJING INFORMATION SCI & TECH UNIV

Equivalent stiffness and damping measurement method and device of piezoelectric energy feedback suspension

The application provides a piezoelectric energy feedback suspension equivalent stiffness and damping measurement method and device, and relates to the technical field of suspension stiffness and damping measurement. The method comprises the following steps: building a test platform; simulating the motion process of the excitation gear and the piezoelectric cantilever beam when the piezoelectric energy feedback suspension vibrates, obtaining the vibration displacement of the free end of the piezoelectric cantilever beam, and measuring the voltage signal generated by the piezoelectric cantilever beam during the vibration process; obtaining the speed change curve of the free end of the piezoelectric cantilever beam based on the change of the vibration displacement with time; drawing the voltage change curve of the piezoelectric cantilever beam during the vibration process according to the voltage signal; obtaining the continuous stiffness of the piezoelectric cantilever beam, so as to obtain the equivalent stiffness and equivalent damping of the piezoelectric energy feedback suspension. The application can measure the equivalent stiffness and damping of the piezoelectric energy feedback suspension, and provides a theoretical basis for the dynamic characteristic analysis and real vehicle application of the piezoelectric energy feedback suspension.
Owner:HUBEI UNIV OF ARTS & SCI

A Timoshenko beam model equivalent method and system of a corrugated steel plate support structure

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.
Owner:SHANDONG UNIV +1

Chain calculation method of suspension steel structure support system based on elastic stability theory

The application provides a chain calculation method of a suspension type steel structure support system based on elastic stability theory, and belongs to the field of foundation pit support, and comprises the following steps: a mechanical calculation model is established, the stiffness of the first layer truss and the suspension component is synthesized into equivalent stiffness according to a series coupling relationship, and the support effect of the upper structure on the support component is equivalent to an elastic support; based on the mechanical model, a deformation coordination equation is established by using the force method principle, a flexibility matrix is constructed, and the second order effect caused by the axial force and the rotation and translation coupling effect are considered; the last support component is taken as a starting point, each support component is sequentially solved from bottom to top, the support reaction force of the current support component at the elastic support is taken as an equivalent external load and is applied to the corresponding elastic support of the adjacent upper support component, and the internal force and deformation distribution of the whole suspension type steel structure support system are obtained by combining the deformation coordination equations of each support component. The method avoids the problem of large calculation workload of the finite element method.
Owner:CENT RES INST OF BUILDING & CONSTR CO LTD MCC GRP +1

Six-stable piezoelectric vibration energy harvester and method for determining the number of stable states thereof

The application discloses a six-stable-state piezoelectric vibration energy collector, which comprises a base, a cantilever beam, ring magnets, rectangular magnets, MFC piezoelectric sheets and wires. The six-stable-state design of the collector is realized by finely adjusting the equivalent stiffness of the piezoelectric beam, the size and magnetization intensity of the magnets, and the spatial layout of the magnets. When the base is subjected to external excitation in the vertical direction, the MFC piezoelectric sheet on the cantilever beam is subjected to extrusion to generate a voltage difference, and the vibration energy is effectively converted into electric energy. The traditional six-stable-state system needs at least six magnets, and the application only needs to configure four magnets to realize the six-stable-state characteristics. The application not only greatly simplifies the design, simulation and installation process of the multi-stable-state collector, but also brings a new breakthrough to the piezoelectric energy collection technology; and the application also provides a scientific method for determining the stable-state number of the collector, lays a solid theoretical foundation for the manufacture and application of the collector, and has a wide application potential.
Owner:XIDIAN UNIV HANGZHOU RES INST

Railway beam bridge damping system based on metal damper coordination and design method

The invention relates to the technical field of earthquake resistance of bridge engineering, and particularly discloses a railway beam bridge damping system based on metal damper coordination and a design method.The railway beam bridge damping system adopts direct displacement design based on equivalent linearization and comprises the steps that firstly, shock insulation displacement and an initial equivalent damping ratio are set as design parameters; the design displacement target is achieved within the reasonable range of the two parameters, accurate calculation can be conducted according to specific structural requirements, blind accumulation only based on the number of existing dampers in previous design is avoided, and design pertinence and scientificity are effectively improved. On the premise that different metal dampers are combined, the independent design of the equivalent damping ratio and the equivalent rigidity is achieved, the flexibility of the damping design is improved, the damping design of a common railway beam bridge is optimized, and the cost of the damping device is reduced.
Owner:CHINA RAILWAY ERYUAN ENGINEERING GROUP CO LTD +1

A method for identifying non-linear parameters of structural clearances

ActiveCN115730517Bsimple processPhysical concepts are clearSustainable transportationBiological modelsMathematical modelLinear Parameter Identification
The present invention discloses a method for identifying nonlinear parameters of structural clearances. First, a mathematical model of the structural clearance nonlinear system is established; then, the frequency response function of the system under sinusoidal sweep excitation is obtained through the input-output response of the system; in the frequency response function, a pair of symmetric displacement points exist at any displacement response amplitude to define the same displacement frequency response function. By defining the real and imaginary parts of the displacement frequency response function through the symmetric displacement FRF points at each given displacement response amplitude, the natural frequency of the system related to the displacement response amplitude can be obtained; then, the expression of the nonlinear equivalent stiffness of the system is extracted through the simulation analysis of the model, and the equivalent stiffness curve of the system is further obtained through the model simulation data; finally, based on the particle swarm algorithm, the clearance characteristic parameters are obtained by curve fitting according to the equivalent stiffness expression obtained by integration and the equivalent stiffness curve obtained by model simulation; the present invention can identify the clearance nonlinear parameters more quickly and accurately globally.
Owner:NORTHWESTERN POLYTECHNICAL UNIV

Construction method of energy-saving sloping roof disassembly-free cement fiber truss plate system

The invention relates to the technical field of disassembly-free cement fiber truss plate construction, in particular to a construction method of an energy-saving sloping roof disassembly-free cement fiber truss plate system, which comprises the following steps: determining an initial support distance based on the daily average temperature difference between the roof slope angle of a sloping roof and the construction period; a formwork supporting system is installed, and truss plates are laid and fixed to serve as permanent formworks; a grading test load is applied to the permanent formwork, and whether the real-time safety margin of the formwork supporting system is qualified or not is determined based on the load ratio of the critical yield load to the designed wet concrete load, so that the initial equivalent stiffness is optimized; based on the distance deviation between the initial supporting distance and the actual supporting distance, the reinforcing mode of the formwork supporting system is determined; concrete is poured on the reinforced formwork supporting system and vibrated and compacted, and the preset ratio is optimized based on the compactness characterization value of the concrete layer after vibration is finished; curing of the concrete layer is completed, acceptance check is conducted, and construction of the truss plate system is completed. The construction safety risk is reduced.
Owner:BEIJING URBAN CONSTR GROUP

Impact resistance design method for high-overload gyroscope based on multi-section trial function energy method

The invention discloses a high-overload gyroscope impact resistance design method based on a multi-section trial function energy method, and belongs to the technical field of micro electro mechanical system structure design. Comprising the following steps: constructing a physical model; establishing a trial function; calculating out-of-plane bending flexibility of the novel structural beam; introducing a torsion correction term and an outer frame equivalent flexibility; the flexibility is accumulated, and the reciprocal is taken to obtain the out-of-plane total rigidity; and the out-of-plane rigidity is applied to construction of an impact kinetic equation. A traditional Euler-Bernoulli beam theory cannot effectively consider the influence of rigidity coupling and torsional deformation of multiple sections of beams and the rigidity of an outer frame on the overall rigidity of a structure. According to the method, the out-of-plane equivalent stiffness of the novel structural beam and outer frame combined structure can be quickly estimated and obtained, the obtained stiffness parameter is applied to dynamic characteristic analysis of the gyroscope, and effective theoretical support is provided for design and engineering application of the novel structural beam structure of the high-overload gyroscope in the out-of-plane direction.
Owner:CHONGQING UNIV OF POSTS & TELECOMM

Photovoltaic module frame and connecting piece optimization method and system based on strength test

The invention belongs to the technical field of photovoltaic power generation engineering structure test and optimization, and provides a photovoltaic module frame and connecting piece optimization method and system based on a strength test, and the method comprises the steps: fixing two ends of a frame through a preset tensile test upper clamp, fixing a purline through a preset tensile test lower clamp, and carrying out a tensile test; through the action of a preset shear test upper clamp on the frame, the purline is fixed by the frame through a shear test lower clamp, and a shear test is carried out; according to the tensile measurement rigidity, the temperature correction coefficient and the pre-tightening force attenuation coefficient, correcting to obtain the tensile equivalent rigidity under the actual working condition; correcting to obtain the shear equivalent stiffness under the actual working condition through the linear section slope and the environment friction correction coefficient; the difference between the environment such as temperature and the actual working condition environment of photovoltaic module service is considered, module optimization is performed through the actual working condition tensile equivalent stiffness and the actual working condition shear equivalent stiffness obtained through correction, and the photovoltaic module optimization effect is ensured.
Owner:SHANDONG ELECTRIC POWER ENG CONSULTING INST CORP

A method for updating a dry mode model of a hydraulic turbine rotor and related devices

The application discloses a kind of water turbine rotor dry mode model updating method and related device, comprising: forming numerical modal family;Equivalent boundary parameter and key connecting surface equivalent stiffness are set;Under the predetermined rotating speed set, calculate centrifugal prestress;On the basis of the centrifugal prestress, consider gyroscopic effect, sequentially solve each rotating speed condition, obtain the natural frequency and vibration mode branch varying with rotating speed;Identify test frequency, damping and vibration mode;With adjacent sector vibration mode phase difference consistency and vibration mode energy distribution as criterion, carry out node radial number determination to test vibration mode, and with the numerical modal family is matched one by one;With the deviation of test frequency and mode assurance criterion as comprehensive target, the equivalent boundary parameter and key connecting surface equivalent stiffness are carried out inversion updating, until meeting preset convergence criterion, complete the updating of water turbine rotor dry mode model, the method and related device can reduce model scale and improve solving convergence.
Owner:XIAN THERMAL POWER RES INST CO LTD

Vibration reduction device for warp knitting machine bed and method thereof

PendingCN122429194APhysicsHydraulic pressure
The present application relates to the field of textile machinery and equipment damping, specifically warp knitting machine bed damping device and method thereof; containing damping base, negative Poisson's ratio lattice metal bearing framework, corrugated air chamber, venturi micro flow channel, composite fluid and electromagnetic coil and controller and other modules; The system fills the shear thickening and magnetorheological mixed composite fluid in the bearing cavity, cooperates with the bearing framework with three-dimensional interconnected pores, and occurs local shear thickening under high frequency impact; The core is that the controller extracts the high frequency vibration characteristics of the main shaft motor, combines the air chamber pressure pulse to solve the dynamic kinetic energy and total stiffness demand, and actively adjusts the electromagnetic coil current and duty cycle; The present application effectively avoids the dynamic hardening defect of traditional hydraulic damping, and realizes the active adjustment type energy consumption and self-adaptive compensation of equivalent stiffness for high frequency periodic impact.
Owner:福建俊诚纺织有限公司 +1

Ship mooring piece split design method based on multi-process forming parameter optimization

The invention discloses a ship mooring part split design method based on multi-process forming parameter optimization, and relates to the technical field of ship structural part precision forming and process optimization design. The method comprises the following steps: generating a plurality of candidate split structure schemes and corresponding multi-process forming paths; working procedure state vectors used for representing the equivalent stiffness, the plate thickness change and the residual stress after the single-section structure is formed are constructed; establishing a cross-process state association mechanism based on process state vector recursion; based on the cross-process state correlation mechanism, stability analysis is conducted on forming parameters within the process disturbance range, and a forming parameter robust value interval meeting the target assembly precision requirement is determined; and performing quantitative comparison and optimization on each candidate split structure scheme based on the value interval. The technical problems that in the prior art, split design of ship mooring pieces depends on experience, the multi-process forming coupling effect is difficult to quantitatively evaluate, the assembly precision is difficult to guarantee, and the process robustness is insufficient are solved.
Owner:DALIAN YONGPENG JINNUO HEAVY HEAD CO LTD

Flexible thin-wall crossed roller bearing multi-target parameter optimization method

A flexible thin-wall crossed roller bearing multi-target parameter optimization method relates to the technical field of bearing design, and comprises the following steps: 1, establishing a parameterized system model containing a shaft system, a thin-wall crossed roller bearing and a box body assembly relation, the bearing model being determined by geometric and assembly parameters; 2, carrying out finite element modeling on the inner / outer ring of the bearing, and carrying out polycondensation on the degree of freedom of an interface to obtain an equivalent stiffness matrix; 3, inputting working conditions and material parameters, and setting a design variable feasible region and constraints; 4, coupling a mapping matrix to solve load distribution, calculating the maximum contact stress and the life damage rate, and constructing a dual-objective optimization model; 5, performing test design to obtain response data, and performing multi-target algorithm iterative optimization to obtain a Pareto optimal solution set; and 6, screening the solution set, and outputting a structure parameter combination meeting the requirement. The method can solve the problems that in the prior art, it is difficult to consider calculation efficiency and ferrule flexibility effect precision, and it is difficult to conduct rapid iterative optimization on roller load distribution and life / contact stress indexes.
Owner:HENAN UNIV OF SCI & TECH

Preliminary design fast estimation method and system for tower deviation of multi-tower cable hoisting system

PendingCN122388311AEquivalent stiffnessTower
The application discloses a preliminary design rapid estimation method and system for tower deviation of a multi-tower cable hoisting system, and relates to the field of tower deviation estimation in bridge construction technology.The estimation method comprises the following steps: calculating the single-span horizontal elastic stiffness of each span compression tower cable based on an equivalent elastic modulus method; calculating the total equivalent stiffness of each tower according to a series stiffness model, specifically comprising the following steps: first, calculating the corresponding left series stiffness and right series stiffness, and then adding the left series stiffness and the right series stiffness to the self equivalent stiffness of the tower to obtain the corresponding total equivalent stiffness; when a single tower is subjected to an external force, calculating the self deviation and the collaborative deviation of the adjacent tower based on a deviation influence coefficient; and when multiple towers are simultaneously subjected to force, calculating the total deviation of any tower by using a superposition principle.The application is suitable for rapid scheme comparison and selection in the preliminary design of a multi-tower cable hoisting system with any number of spans and towers, and has the advantages of strong universality, reliable precision, easy implementation and the like.
Owner:SICHUAN ROAD & BRIDGE CONSTRUCTION GROUP CO LTD

Full-band vibration reduction design method for metamaterial pipe based on multiple band gaps

PendingCN122366014AMechanical modelsResonance
This invention relates to a full-frequency vibration reduction design method for metamaterial pipelines based on multiple band gaps, comprising: establishing an equivalent mechanical model of the target pipeline; periodically arranging elastic supports on the target pipeline to induce the formation of a zero-frequency band gap and a Bragg band gap, coupling the equivalent support stiffness of the elastic supports with the equivalent mechanical model of the pipeline to construct a first band gap calculation model; periodically arranging local resonant vibration absorbers on the target pipeline to form a local resonant band gap, coupling the equivalent stiffness and equivalent mass of the local resonant vibration absorbers into the first band gap calculation model to obtain a second band gap calculation model; constructing a system finite structure dynamic vibration calculation model with a second assembly as the analysis object; constructing a vibration transmissibility index, and using the system finite structure dynamic vibration calculation model as a fitness evaluation tool for a genetic algorithm to perform non-periodic optimization of the elastic support positions, solving for the optimal arrangement position of the elastic supports with the largest bandwidth of the zero-frequency band gap.
Owner:NAT UNIV OF DEFENSE TECH

Mooring device for tension leg platform pool test and test method

The invention provides a mooring device for a tension leg platform pool test and a test method. The device comprises a first mooring rope, an extension spring and a second mooring rope which are connected in sequence, and the second mooring rope is connected with a tensioning mechanism; the specification of the cable meets the conditions that A is the sectional area of the cable, k is the safety coefficient, Tmax is the maximum expected tension, sigmaallow is the allowable stress of a cable material, d is the diameter of the cable, L is the effective stress length of the cable, R is a judgment threshold value, Ks is the rigidity of an extension spring, E is the elastic modulus of the cable material, and model selection is conducted on the cable according to the target tension force range; the system equivalent stiffness Ktot in the test is ensured to be dominated by the extension spring, the contribution of the cable stiffness to deformation can be ignored, and the accuracy of equivalent stiffness control of the pool test and the repeatability of the test are improved.
Owner:POWERCHINA ZHONGNAN ENG +1

Low-frequency damping device suitable for pipelines of various specifications

The invention relates to the technical field of pipeline vibration reduction, in particular to a low-frequency vibration reduction device suitable for pipelines of various specifications. The upper circular hoop and the lower circular hoop are oppositely arranged and are connected through a bolt; the plurality of softened rigidity annular pads are arranged on the inner sides of the upper circular hoop and the lower circular hoop at intervals; the side faces of the two softening rigidity annular pads are arranged on the two sides of the lower circular hoop in an attached mode respectively. The softening rigidity base and the softening rigidity annular pad are both made of elastic materials. The softening rigidity base is provided with a plurality of base vibration reduction holes, and the base vibration reduction holes are spaced through oblique and long base curved beams and vertical and short base center rods. The softened rigidity annular cushion is provided with an annular cushion center hole and a plurality of annular cushion side holes which are spaced through annular cushion curved beams. The vibration response of pipelines of different specifications under the low-frequency working condition can be remarkably reduced, and therefore effective control over low-frequency vibration is achieved; and the overall deformation and the equivalent stiffness of the pipeline system can also be regulated and controlled so as to meet the requirements of different working conditions.
Owner:BEIJING INST OF TECH

Bridge pier sinking support rebound displacement compensation device and design method thereof

The invention provides a pier sinking support springback displacement compensation device and a design method thereof, and relates to the technical field of pier sinking support springback displacement compensation. The method comprises the steps that the actual settlement displacement (d-h) of a bridge deck is obtained according to the upward displacement compensation amount h of the compensation device and the creep sinking amount d of a pier, calculating to obtain compensation device support loss force P according to the equivalent stiffness coefficient k1 of the upper structure, and further obtaining a sinking ratio P / P according to the compensation device support loss force P and preset original support loss force P; judging whether the sinking ratio P / P is smaller than a preset threshold value or not; if not, adjusting the total rigidity k3 of the spring, and returning to execute the step of acquiring the total rigidity k3 of the spring according to the adjusted total rigidity k3 of the spring until the sinking ratio P / P is smaller than the preset threshold value, and outputting device information of the compensation device to design the compensation device. The technical problems that in the prior art, a common rubber support cannot achieve rebound displacement automatic compensation and is prone to fatigue failure are solved.
Owner:COMM DESIGN INST CO LTD OF JIANGXI PROV

Dynamic modeling method for pipeline system containing movable pipe joint

The invention relates to the technical field of mechanical dynamics, in particular to a dynamic modeling method of a pipeline system containing a movable pipe joint, which comprises the following steps: establishing a movable pipe joint-pipeline system dynamic model based on a finite element method, in the dynamic model, establishing a model of a pipeline and a joint part according to a Tiushingeshu beam theory, and establishing a model of the pipeline and the joint part according to the Tiushingeshu beam theory; the equivalent stiffness of the movable pipe joint under the pre-compression state and the dynamic load of the sealing ring is considered; performing model verification on the established movable pipe joint-pipeline system dynamic model to obtain a verified model; and based on the verified model, simulating the influence of each excitation amplitude on the inherent frequency of the movable pipe joint-pipeline, and verifying the correctness of the movable pipe joint-pipeline system dynamic model. According to the method, the dynamic model of the aero-engine pipeline system containing the movable pipe joint is accurately constructed, and the inherent characteristics and the vibration response law of the system are accurately represented.
Owner:NORTHEASTERN UNIV CHINA

A method, apparatus and electronic device for characterizing the boundary stiffness of a lattice structure

The present disclosure provides a method, device and electronic equipment for characterizing the boundary stiffness of a lattice structure, belonging to the field of material mechanics and structural design. The present disclosure divides the lattice structure, obtains the divided lattice unit, determines the type of the lattice unit, and the type is used to indicate the integrity of the lattice unit. Based on the type and the rod boundary condition of the lattice unit, the equivalent stiffness of the lattice unit is determined. The rod boundary condition is used to indicate the stress constraint state of the rod. In this way, compared with the existing fixed calculation method of heterogeneous multi-scale finite elements, the present disclosure can adopt differentiated flexible mechanical calculation for lattice units of different integrity types combined with their specific rod boundary conditions, avoiding errors caused by uniform calculation. In summary, the technical solution provided by the present disclosure can improve the accuracy of characterizing the boundary stiffness of the lattice structure, reduce error accumulation, and can adapt to various application scenarios.
Owner:NINGBO INST OF MATERIALS TECH & ENG CHINESE ACAD OF SCI +1

Method and device for calculating rigidity and damping of fluid supporting tilting pad sliding bearing

The invention discloses a method and device for calculating rigidity and damping of a fluid bearing tilting-pad sliding bearing, and the method comprises the steps: calculating the rigidity and damping of the fluid bearing tilting-pad sliding bearing according to an equivalent rigidity and equivalent damping calculation model of an original fluid bearing tilting-pad sliding bearing based on a mechanical vibration theory; the method comprises the following steps: respectively analyzing four groups of rigidities and damping of a rigidity and damping calculation model of the fluid supporting tilting-pad sliding bearing to obtain four groups of single-degree-of-freedom systems, modeling the single-degree-of-freedom vibration systems, and constructing a mechanical vibration model; excitation and measurement response are independently performed in the four directions, so that four groups of single-degree-of-freedom vibration data can be obtained; processing the four groups of single-degree-of-freedom vibration data by using a component analysis method, testing given excitation to obtain response, and calculating to obtain modal parameters; and calculating the rigidity and damping of the fluid-supported tilting-pad sliding bearing according to the modal parameters. The method has the advantages of being comprehensive in calculation and higher in accuracy, and provides technical support for the design of a fluid bearing tilting-pad sliding bearing rotor system.
Owner:HANGZHOU VOCATIONAL & TECHN COLLEGE