24 results about "Linear elasticity" patented technology

The invention relates to the technical field of petroleum and natural gas drilling engineering, and particularly discloses a multi-field coupled complex fractured formation fracture width distribution inversion method, which is characterized in that a drilling fluid leakage model considering a fluid-solid coupling effect is constructed based on a porous elastic mechanics theory, and a roughness correction factor is introduced to correct a traditional cubic law; the application of the Darcy law in the matrix is perfected, a matrix and crack coupled drilling fluid leakage mathematical model is established, the influence rule of key parameters such as fluid viscosity, pressure difference and crack width on the drilling fluid leakage amount is obtained through numerical simulation, and on the basis, the drilling fluid leakage amount is calculated. According to the method, the crack width multiple linear regression inversion equation with the fluid viscosity, the pressure difference and the accumulated leakage as independent variables is established, the inversion equation has high prediction precision and practicability and can be used for rapidly and accurately inversing the crack width on site, and theoretical and technical supports are provided for multi-scale fractured formation leakage mechanism understanding and leakage prevention and control optimization.

The invention discloses a stay cable analysis digital twinborn model construction method, which comprises the following steps of: constructing a stay cable space three-dimensional vibration motion partial differential equation based on a material linear elasticity hypothesis and a double-coordinate system theory, and setting boundary conditions and initial conditions of the stay cable space three-dimensional vibration motion partial differential equation; a Galerkin multi-mode truncation method is adopted to obtain a displacement function of superposition of an end displacement excitation item and a vibration mode item; deducing a three-way strong coupling ordinary differential equation set through symbolic operation, and solving by using a step-variable Runge-Kutta algorithm to obtain a stay cable analysis digital twin model with stable parameters; structural response data are obtained through the sensor network and calculated, and when the obtained cable force, flexural rigidity and damping ratio exceed threshold values, a model updating mechanism is triggered for updating; and then the updated stay cable analysis digital twin model is obtained. According to the method, the real dynamic characteristics of the stay cable can be restored with high precision, and effective support is provided for structural state evaluation and early warning.

This invention relates to the field of shape memory alloy technology, specifically providing a zero-hysteresis giant linear elastic Ni-Fe-Ga shape memory alloy microwire and its preparation method. The preparation method of the alloy microwire includes: ① preparing austenitic alloy microwires using a glass coating method; ② inducing the austenite in the microwires into a full martensite structure through stress aging treatment and maintaining it at room temperature; ③ finally introducing some austenite into the martensite alloy microwires through annealing treatment, obtaining a wire material with a stable austenite / martensite coexistence structure at room temperature. The Ni-Fe-Ga ternary shape memory alloy microwires provided by this invention exhibit both zero hysteresis and giant linear elasticity characteristics under external force, with a maximum elastic strain of up to 7.7%, and the preparation method is simple, showing broad application prospects in high-precision micro-actuators and sensing fields.

The application discloses a kind of compressed air energy storage cavern operating pressure determination method, comprising the following steps: establishing the elastic mechanics plane strain model of surrounding rock-lining-sealing layer composite structure, deducing the analytical solution of elastic stress and displacement of composite structure;Determine the upper limit of cyclic internal pressure;Introduce the spatial heterogeneity function of surrounding rock parameter, deduce the elastoplastic stress and plastic zone radius expression of composite structure;Introduce the fatigue damage evolution equation to correct rock mass strength parameter, based on the plastic zone radius control condition, solve lower limit pressure.The method can simultaneously utilize initial geostress to constrain surrounding rock deformation and quantify the attenuation of rock mass parameters caused by long-term cyclic loading, while ensuring that surrounding rock does not produce tensile failure and the expansion of plastic zone is controllable, the best operating pressure range and amplitude of compressed air energy storage cavern in the whole life cycle of up to 30 years are accurately quantified, so as to ensure the long-term sealing and safety of the structure, effectively optimize the design parameters, and improve the engineering economy.

This invention discloses a control method for a forklift telescopic boom, which includes a primary boom, a secondary boom, a tertiary boom, and a quaternary boom arranged nested from the inside out; it also includes: a drive cylinder, the cylinder body of which is hinged to the outside of the primary boom, and the piston rod of which is hinged to the secondary boom; a first sprocket and a first chain, the first sprocket being mounted outside the secondary boom; one end of the first chain being fixed to the head of the primary boom and the other end being fixed to the tail of the tertiary boom; this invention overcomes the limitations of traditional length calculations that rely solely on geometric ratios, and innovatively introduces an elastic correction model that includes linear elasticity coefficients and gravity gain coefficients, which can dynamically calculate the elastic elongation of the chain caused by gravity and angle changes based on the real-time piston rod stroke and luffing angle. This allows the control system to obtain boom length data closer to physical reality under dangerous working conditions with high luffing angles and long extensions.

The invention relates to a nonlinear structure reduced-order model construction method based on sparse recognition and a mixed mode, belongs to the technical field of structural dynamics analysis and aeroelastic mechanics analysis, and solves the problem that complex motion caused by geometric nonlinearity under large deformation cannot be accurately described in the prior art. Comprising the following steps: S1, establishing a nonlinear finite element model of a target large flexible wing to obtain a training data set; s2, solving a mixed modal basis based on the displacement residual error and SVD (Singular Value Decomposition); s3, establishing a nonlinear stiffness coefficient solving problem model, introducing LASSO regression to establish an LASSO regression optimization objective function, and solving to obtain a sparse nonlinear stiffness coefficient; s4, based on the sparse nonlinear stiffness coefficient and the structural kinetic equation, establishing a nonlinear structure reduced-order model; and S5, applying the nonlinear structure reduced-order model to statics response solution and dynamics response solution of the large flexible wing to obtain statics response and dynamics response results.

The invention provides a woven composite material multi-scale analysis method based on clustering order reduction, and belongs to the technical field of composite material multi-scale damage evolution evaluation. The method comprises the following steps: 1, defining a microscopic damage constitutive model; defining a fiber damage constitutive equation and a matrix damage constitutive equation; 2, solving an RVE damage problem by using an SCA method; the method comprises the following steps: for a composite material RVE region, converting a control equation of elastic mechanics into a solving L-S equation by introducing reference stiffness; the SCA method comprises an offline stage and an online stage. Step 3, establishing an FE-SCA2 concurrent three-scale model; and the numerical value is solved. According to the method, the problem of low three-scale calculation efficiency is relieved while nonlinear calculation high precision is achieved, and the method has high application value in the field of composite material structure multi-scale calculation.

The application belongs to the field of bridge health monitoring and rapid detection, and discloses a bridge bending stiffness identification method based on multi-point deflection influence line input, and steps are as follows: firstly, a linear model for solving bending stiffness is established by using measured deflection influence lines at multiple positions of a bridge and linear elasticity theory; then, a redundant dictionary composed of multiple types of global basis functions is used for sparse representation of the bending stiffness distribution curve, and the bending stiffness reconstruction problem is converted into a sparse vector solving problem; finally, a sparse vector solution model with 1-norm regularization constraint is established, and the optimal bending stiffness distribution is obtained by solving the model. l The application can realize continuous bending stiffness curve solving by using multi-point measured deflection influence lines only, is suitable for stiffness evaluation of statically indeterminate in-service bridges such as continuous girder bridges, and has the advantages of strong applicability, high solving efficiency and strong robustness.

The invention provides a hard rock elastic mechanical parameter obtaining method and device under the eccentric loading condition, and belongs to the technical field of optical measurement and numerical simulation. The method comprises the steps that first displacement is obtained through a uniaxial loading experiment; introducing an eccentric loading coefficient, and calculating in finite element software to obtain a second displacement; establishing a multi-target error function according to the first displacement and the second displacement; outputting the final elastic modulus, Poisson's ratio and eccentric loading coefficient under the condition that the multi-target error function reaches the convergence condition; under the condition that the multi-objective error function does not reach a convergence condition, iteratively optimizing mechanical parameters by adopting a simulated annealing particle swarm optimization algorithm improved by a dynamic cooling strategy based on particle swarm diversity, and incorporating an eccentric loading coefficient into a to-be-inverted parameter; according to the method, the inversion analysis of the rock elastic mechanical parameters and the eccentric loading coefficient is realized, and the inversion precision is improved by adopting the improved simulated annealing algorithm.

The invention discloses a method for rapidly predicting the elastic-plastic mechanical property of a one-dimensional periodic spiral winding structure, and relates to the technical field of spiral winding structure mechanical property prediction. Comprising the following steps: S1, constructing a finite element model of a one-dimensional periodic spiral winding structure, performing linear elasticity analysis on the finite element model, and extracting a strain concentration tensor; s2, based on the extracted strain concentration tensor, clustering the finite element model by using a clustering algorithm to obtain a reduced-order model after partitioning, and calculating an interaction matrix representing a mechanical relationship between blocks in the reduced-order model; and S3, inputting the interaction matrix into an online incremental algorithm to obtain an elastic-plastic stress-strain curve of the one-dimensional periodic spiral winding structure, and realizing prediction of the elastic-plastic mechanical property of the one-dimensional periodic spiral winding structure. According to the method, the elastic-plastic mechanical property of the one-dimensional periodic spiral winding structure can be efficiently and accurately predicted, and the analysis efficiency and optimization efficiency of the one-dimensional periodic spiral winding structure are improved.

The invention provides a finite element grid rapid reconstruction method based on linear elastic mechanics, which comprises the following steps of: after all node displacement vectors are obtained, superposing all node displacement vectors to all corresponding node coordinates before deformation to obtain all node coordinates after deformation: in the formula, the node coordinates after deformation and the node coordinates before deformation are shown in the description; keeping the corresponding relation between the units and the node numbers unchanged, and modifying node coordinates in the finite element solving file to complete finite element grid reconstruction; calculating a Jacobian determinant, a length-width ratio and a warping factor index of the reconstructed grid, and judging whether Jacobian determinants gt of all units are reconstructed or not; 0.5, the length-width ratio is lt; 5, a warping factor lt; and when 6.5, if yes, determining that the finite element mesh meets the use requirement. According to the method, a physical and geometric dual-drive grid deformation mechanism is established, global displacement distribution is restrained through a linear elastic mechanical constitutive equation, deformation of non-reasonable units is restrained, and the problem of unreasonable topology caused by a traditional geometric interpolation method is solved.

The invention relates to a shotcrete support parameter adaptability design method considering blasting damage, and belongs to the technical field of tunnel engineering. The problems that the friction coefficient value is empirical, parameter design is not matched with the actual working condition and the design accuracy is low due to neglecting of the shape change of the surface of the surrounding rock caused by blasting damage in the prior art are solved. According to the technical scheme, the method comprises the steps of quantifying a surrounding rock roughness coefficient and calculating a friction coefficient through multi-angle image acquisition and image recognition; the lining thickness is determined by combining the clearance requirement, the deformation allowance and the blasting damage risk; establishing a two-way unequal-pressure elastic mechanical model, and solving lining stress distribution based on a stress function and coulomb friction constraint; and taking support cost minimization as a target, and inversely solving the optimal concrete strength grade and reinforcement ratio by adopting an optimization algorithm. Accurate self-adaptive design of support parameters is realized, stress calculation precision is improved, safety is guaranteed, and cost is reduced.

The invention provides a reinforced concrete structure reinforcement calculation process and method, and the method comprises the following specific steps: carrying out the linear elasticity analysis of a plain concrete structure, calculating the internal force of the plain concrete structure, and calculating the initial reinforcement ratio of the concrete structure meeting the bearing capacity limit state; a preliminary reinforcement scheme is given on the basis of the preliminary reinforcement ratio of the structure; and performing nonlinear finite element analysis on the reinforced concrete structure, calculating a concrete damage state and reinforcement stress, performing crack width checking calculation, and adjusting a preliminary reinforcement scheme. According to the method, the requirements of the bearing capacity limit state and the normal use limit state can be met at the same time, the process is clear, and powerful technical support can be provided for reinforcement design of a reinforced concrete structure.

The application discloses a shale bedding fracture propagation geometric parameter calculation method, which comprises the following steps: establishing a differential equation group of a shale bedding standard layer according to an elastic mechanics theory, integrating the differential equation group into a partial differential equation group; transforming the partial differential equation group into a common differential equation group, and solving a general solution of the common differential equation group; solving constants in the general solution of the common differential equation group by using a linear spring controlled bedding boundary condition; obtaining a shear slip calculation model of the shale bedding under a space coordinate system; establishing a geometric parameter calculation equation of a shale bedding fracture, and coupling the shear slip calculation model of the shale bedding to obtain a shale bedding fracture propagation geometric parameter calculation model; and performing dynamic simulation on a fracture propagation in a shale gas volume fracturing process, and obtaining a calculation result of a shale bedding fracture propagation geometric parameter. The calculation result of the shale bedding fracture propagation geometric parameter obtained by the application is reliable, and provides a technical reference for shale gas exploration and development and other related work.

This invention discloses a method for calculating the energy release rate of delamination damage propagation in composite materials based on shell elements, belonging to the field of composite material delamination damage modeling and efficient energy release rate calculation. The method includes: deriving an equivalent energy release rate calculation method based on energy differential, and proposing a simplified formula for calculating the structural energy release rate under the linear elasticity assumption of the material. Undamaged regions are established using multi-layered plate and shell elements after delamination, and structural damage analysis models are constructed under different damage sizes, structural load conditions, and displacement boundary conditions. The structural response under different damage sizes is calculated and a database is formed. The relationship between damage size and structural strain energy or overall flexibility and stiffness is fitted using a polynomial isofunction fitting method, establishing a reduced-order model for calculating the energy release rate of delamination damage propagation with damage size and external load as inputs. This invention is used to quickly calculate the energy release rate of delamination damage propagation in composite materials, supporting rapid online safety assessment of composite structures.

The invention provides a constitutive model establishment and transient dynamic analysis method considering a plastic domain, and relates to the technical field of constitutive relation and dynamic analysis. The method comprises the following steps: introducing plastic strain parameters corresponding to the yield strength of a material into a J-C constitutive equation at normal temperature, establishing a constitutive model considering a plastic domain, and fitting and solving each parameter in the established constitutive model through test data to obtain a solved constitutive model; the solved constitutive model is subjected to numerical simulation and is compared with test data, so that the reasonability of the solved constitutive model can be verified; the stress deconservative property is verified by establishing an explicit dynamic finite element model and carrying out linear elasticity analysis and elastic-plastic analysis; the method can provide reference for plastic domain constitutive model establishment and transient dynamics deconservative analysis.

The invention relates to an acousto-optic tunable filter (AOTF). The acousto-optic tunable filter (AOTF) is an electric control tunable spectrum light splitting element, and the diffraction performance of an AOTF device is influenced by the sound field distribution in the AOTF. Sound field distribution in an existing AOTF device mainly considers that a sound field only comprises a single sound mode which is propagated in a specific direction and has a single wavelength. Therefore, the invention provides the analysis method for the acoustic mode distribution in the AOTF device, and the amplitude of each acoustic mode in the AOTF device is solved and obtained by establishing a non-homogeneous linear equation set through the elastic mechanical boundary condition of the AOTF device and the anisotropic solid constitutive equation. Compared with an existing AOTF device internal sound field modeling method, the AOTF device internal sound mode distribution analysis method provided by the invention has the advantages that a three-dimensional steady-state sound field in the AOTF device can be dispersed into superposition of different sound modes; the method can effectively calculate and analyze the influence of multiple reflections and mode conversion of sound waves on each solid surface of the AOTF device on sound field distribution, and is suitable for any crystal material.

The application discloses a shield tunnel-soil dynamic interaction simulation method based on OpenSees, and comprises the following steps: S1, setting boundary conditions, and establishing a tunnel-soil dynamic interaction finite element model; S2, performing gravity analysis on the tunnel-soil dynamic interaction finite element model; S3, performing zero-clearing processing on soil displacement; S4, adding shield tunnel segment, joint bolt and compression-resistant rubber gasket material unit and material information, and setting a contact surface between the tunnel and the soil; S5, binding a nonlinear beam unit based on a fiber section to the segment unit, and simulating nonlinear characteristics of the segment; S6, converting soil properties from linear elasticity to elastoplasticity; and S7, performing incremental dynamic analysis on the model, adopting an initial stress field of the soil as an initial state, and applying seismic excitation to the bottom of the model; and the application predicts and evaluates the anti-seismic capacity of the tunnel through the shield tunnel seismic response refined numerical modeling and calculation method.

The present application relates to the technical field of oil and gas drilling engineering, and specifically discloses a multi-field coupling complex fractured formation fracture width distribution inversion method, based on the theory of porous elasticity, a drilling fluid loss model considering fluid-solid coupling effect is constructed, a roughness correction factor is introduced to correct the traditional cubic law, and the application of Darcy's law in the matrix is improved, a drilling fluid loss mathematical model coupled with the matrix and the fracture is established, through numerical simulation, the influence law of key parameters such as fluid viscosity, pressure difference and fracture width on drilling fluid loss is obtained, and on this basis, a fracture width multivariate linear regression inversion equation with fluid viscosity, pressure difference and cumulative loss as independent variables is established, the inversion equation has high prediction accuracy and practicability, can be used for quickly and accurately inverting the fracture width on site, and provides theoretical and technical support for the understanding of the loss mechanism of multi-scale fractured formation and the optimization of leakage prevention and treatment.

The invention relates to the technical field of shield tunnel engineering safety evaluation, in particular to a shield tunnel longitudinal deformation calculation method and system based on a symplectic elasticity theory. The technical problem to be solved by the invention is to overcome the defects that an existing calculation model cannot accurately simulate tunnel segment slab staggering deformation, soil shear continuity is ignored, and the calculation process is complex and low in efficiency. In order to solve the problem, the shield tunnel is dispersed into segment ring units and simplified into Timoshenko beams, and a surrounding soil body is simplified into a Pasternak elastic foundation; the method comprises the following steps of: constructing an element stiffness matrix and assembling a total stiffness matrix by solving a symplectic analysis general solution of a mechanical control equation and taking the symplectic analysis general solution as a shape function by fusing symplectic elastic mechanics and a finite element method, and finally introducing a ground heap load based on a Boussinesq solution, and carrying out simultaneous solution to obtain longitudinal deformation and internal force of a tunnel.

The invention relates to the field of biological medicine, discloses a method and system for inhibiting deformation of a microfluidic consumable in real time, and aims to solve the technical problems that in the prior art, the deformation of the microfluidic consumable is too large due to factors such as temperature and pressure, and the fluid control precision and the service life of the consumable are affected. The method comprises the steps that consumable surface three-dimensional deformation point cloud data are collected in real time through a high-precision optical interference sensor array; constructing a space-time aligned deformation field tensor, and extracting a deformation dynamic feature vector by using a space-time convolutional neural network; and in combination with a physical constraint model based on linear elastic mechanics, solving an optimal suppression force field meeting the conditions that the deformation residue is less than or equal to 5 microns and the stress does not exceed the yield strength of the material. By means of the technical scheme, deformation can be stably restrained within 5 microns, response delay is lower than 2 ms, and the stability and reliability of a microfluidic system in high-precision scenes such as POCT and single cell control are remarkably improved while the structural integrity of the flow channel is guaranteed.

The invention belongs to the technical field of tower drum design, and provides a sectional type concrete fan tower drum structure natural vibration frequency calculation method and system, and the method comprises the steps: building a uniform cross-section iron wood octanolean beam and a variable cross-section iron wood octanolean beam representing the tower drum structure; on the basis of the uniform-cross-section ironwood-octancarpus beam and the variable-cross-section ironwood-octancarpus beam, establishing a dynamic balance differential equation of the ironwood-octancarpus beam; on the basis of the Timoshensincaro beam dynamic balance differential equation, a homogeneous linear partial differential equation is obtained through decoupling; obtaining a characteristic value based on a homogeneous linear partial differential equation; according to the characteristic values, a rotation angle, a shearing force and a bending moment are obtained based on elastic mechanics, so that the natural vibration frequency of the fan tower drum is obtained; and compared with the eigenvalue analysis result of the Rayleigh-Ritz method, the error is reduced, and the precision requirement of the preliminary design stage is met.

The application provides a fracturing casing strength safety evaluation method, device, equipment and medium, and the method comprises the following steps: confirming the strength safety coefficient, the tensile strength safety coefficient and the internal pressure strength safety coefficient according to the internal pressure strength, the tensile strength, the elastic modulus, the Poisson's ratio, the fracturing pump pressure, the fracturing fluid density and the reservoir pressure gradient; the casing strength safety coefficient is the ratio of the casing yield strength and the maximum equivalent stress point stress, the maximum equivalent stress point stress is determined based on the fracturing casing equivalent stress mathematical model established according to the fourth strength theory, and the variables of the fracturing casing equivalent stress mathematical model comprise the radial stress, the hoop stress, the fracturing casing axial stress and the casing shear stress; the fracturing casing axial stress is the sum of the axial tensile stress not considering bending and the bending stress under the bending load, the bending stress and the casing shear stress are confirmed based on the uniformly distributed load simply supported beam physical model, and the uniformly distributed load simply supported beam physical model is solved by the elastic mechanics semi-inverse solution method.

The invention discloses a beam body bearing capacity assessment method based on rigidity distribution identification, and relates to the technical field of civil or bridge structure health monitoring. The method comprises the following steps: firstly, carrying out geometric segmentation on a to-be-evaluated beam body, applying a static load, measuring node deflection and selectively measuring a rotation angle; and constructing a total stiffness matrix by taking the flexural stiffness of each section as an unknown number, constructing an equilibrium equation in combination with boundary conditions and loads, and solving to obtain the distribution condition of the flexural stiffness along the beam length and the flexural stiffness of the minimum beam section. Secondly, by analyzing the consistency of rigidity distribution under different loading grades and comparing with historical data, the linear elasticity condition and damage development of the beam body are judged. And finally, establishing a rigidity and bearing capacity parameter relationship based on the material and section data, and reversely deducing the weakest section bearing capacity and the maximum bearing capacity of the beam body by utilizing the minimum rigidity. The method can accurately position the rigidity weakening area and quantitatively reflect the damage, the identification result is accurate, the operation is simple and convenient, and the cost is low.