149 results about "Rigidity matrix" patented technology

The invention relates to an existing building glass curtain wall operation and maintenance method and system based on a digital base. The method comprises the following steps that curtain wall vibration response data, visible light image data and three-dimensional point cloud data are obtained; based on the curtain wall vibration response data, comparing the current modal parameter with the historical modal parameter, and determining the dynamic characteristics of the curtain wall panel; identifying the curtain wall apparent damage type and the corresponding damage degree based on the visible light image data; based on the three-dimensional point cloud data, a curtain wall live-action three-dimensional point cloud model is constructed and mapped into a numerical model, a local stiffness reduction coefficient is calculated based on curtain wall panel dynamic characteristics, curtain wall apparent damage types and corresponding damage degrees, and a local stiffness matrix of a corresponding unit or node in the numerical model is corrected; and performing finite element analysis on the corrected numerical model to realize performance evaluation and deduction of the glass curtain wall. Compared with the prior art, the method has the advantages that the performance change of the glass curtain wall can be accurately and dynamically sensed and predicted, and the like.

The invention discloses a multi-dimensional aeroelastic calculation method and device based on a nonlinear Euler-Bernoulli beam and a storage medium, and belongs to the technical field of wind turbine aerodynamics, the method comprises the following steps: inputting the stiffness of each section of a blade into a nonlinear Euler-Bernoulli beam equation to obtain a modal-displacement transformation matrix; the rigidity, the weight and the external force of each section of the blade are converted to obtain a generalized rigidity matrix, a generalized mass matrix and a generalized force; starting circulation, substituting into a forced coupling vibration equation, solving modal displacement of each order at the current moment, and inputting into a modal-displacement inverse transformation matrix to obtain blade displacement; the generalized force is substituted into a blade element momentum theoretical formula to solve aerodynamic force at the next moment, the generalized force is updated to obtain updated generalized force, and aerodynamic force at each moment is obtained; and calculating to obtain the multi-dimensional aerobomb. According to the method, the calculation of the blade deformation and the load considers the change of the torsional degree of freedom, and more accurate and more efficient load and deformation calculation can be carried out.

The invention relates to a deep foundation pit lateral displacement calculation method and device, electronic equipment, a medium and a program product. The method comprises the steps that a complete foundation pit BIM model is established based on a BIM family model of each foundation pit engineering component; based on the foundation pit BIM model, determining a calculation model under each excavation step, and based on the calculation model under each excavation step, obtaining a node load matrix under the corresponding excavation step and a stiffness matrix under the corresponding excavation step; and on the basis of the node load matrix under each excavation step and the rigidity matrix under each excavation step, the deformation increment of the supporting structure under each excavation step is obtained, the deformation increments of the supporting structures under each excavation step are overlapped in sequence, and foundation pit supporting deformation under each excavation step is obtained. Therefore, the problems that a full-model finite element analysis mode adopted in the prior art is high in calculation cost and low in efficiency are solved, and the convenience and accuracy of foundation pit lateral displacement deformation prediction work are greatly improved.

The invention discloses a hydrodynamic analysis method for a floating structure with multi-body and multi-coupling characteristics, which comprises the following steps of: acquiring geometric characteristics of each floating body, and dividing boundary element computational grids; wave excitation force, additional mass and radiation damping of each floating body are calculated, and a mass matrix and a rigidity matrix of each floating body are obtained; determining a connection mode and a coupling factor of the floating body; according to a connection mode and coupling characteristics of the system, establishing displacement connection conditions among the floating bodies; constructing a motion constraint matrix according to the displacement continuity condition and the motion constraint relation; determining a frequency domain motion equation of the multi-floating-body system according to a Lagrange multiplier method; and solving the motion equation to obtain the motion response of the multi-floating-body system, and further systematically analyzing the wave energy capture power according to the coupling characteristics of the system. According to the analysis method, the problem that the motion response of each degree of freedom cannot be accurately described when the hydrodynamic response characteristics of the complex multi-body system are obtained through an existing simulation method is solved.

The invention discloses an intelligent compensation method and system for a welding track of a wind-resistant structure of a steel box girder, and the method comprises the steps: obtaining the welding track in real time, and extracting the welding information of the welding track, the welding information comprises the windward area and the wind speed of the steel box girder, the rigidity matrix of the steel box girder, and the temperature gradient, the wind load and the welding stress of each position on the welding track; a welding track compensation model is set, the total compensation amount of the welding track is calculated in real time according to the welding information, and the difference value of the total compensation amount of the ideal track and the total compensation amount of the welding track is calculated to serve as the final track deviation; and welding parameters are adjusted until the final track deviation does not exceed a preset deviation threshold value, and therefore welding track compensation is completed.

The invention discloses a stiffness matrix compression storage method and system based on block symmetry characteristics and a medium, and the method comprises the following steps: constructing a geometric model, and obtaining material attribute parameters; dividing finite element analysis grids according to the geometric model, and numbering units, nodes and degrees of freedom; setting boundary conditions and load applying conditions; a storage space is applied based on the block symmetry characteristic of the global stiffness matrix; calculating an element stiffness matrix, assembling element stiffness matrix information to a global stiffness matrix, and applying a boundary condition; and solving a finite element equation corresponding to the compressed and stored global stiffness matrix by adopting a numerical solution method. According to the method, the reducibility of the stiffness matrix is kept, redundant information stored in the stiffness matrix is reduced, and the time complexity of the stiffness matrix and vector multiplication and other matrix operation is also reduced, so that the solving performance of the linear equation set is effectively improved.

The present application discloses a method and device for modeling and topological optimization design of a reinforced flat plate with an embedded acoustic black hole. The method includes: dividing the design domain into units based on design variables to construct a collaborative optimization model; dividing the reinforced area with solid units and the flat plate area with variable thickness shell units to simulate acoustic black holes; coupling the variable thickness shell units with the solid units and determining the stiffness matrix; introducing maximum size constraints and / or geometric non-interference constraints and / or geometric-topological non-interference constraints and / or draft constraints in the design process; solving the sensitivity of the design variables based on the optimization target combined with the stiffness matrix to obtain the optimization result; if the optimization result does not meet the convergence condition, redefine the design variables based on the sensitivity. It solves the problem that the existing vibration reduction means are difficult to efficiently realize the lightweight vibration reduction design of thin-walled structures. It takes into account the structural stiffness and the vibration and noise reduction characteristics of the medium and high frequencies, realizes the structure-function integrated design, and reduces the dynamic response of the thin-walled structure.

The invention relates to a method for simulating the operation impact load of a wind generating set. The method comprises the steps that aerodynamic load distribution data, elastic structure geometric material parameters, control logic dynamic parameters and environment parameters of the wind generating set are acquired, and initial multi-physical coupling model data are obtained; generating an initial impact load time sequence based on the initial multi-physical coupling model data; according to the initial impact load time sequence, the elastic modulus and the stiffness matrix of the composite material structure of the wind generating set are dynamically adjusted, and updated composite material structure parameters are generated; obtaining a smooth impact spectrum based on the updated composite material structure parameters and the initial impact load time sequence; and according to the smooth impact spectrum, generating impact load simulation data. By adopting the method, potential problems and risks can be found in advance, the design and operation strategy of the wind generating set is optimized, the reliability and economical efficiency of the wind generating set are improved, and the maintenance cost and downtime are reduced.

The invention discloses a self-adaptive clamp adjusting method based on intelligent vision and pneumatic control. The self-adaptive clamp adjusting method is suitable for a multi-variety small-batch flexible manufacturing scene. According to the method, a closed-loop control framework composed of multi-mode sensing, hybrid modeling, dynamic optimization and pneumatic execution is constructed, and precise sensing and rapid compensation of part deformation under the complex working condition are achieved. Submillimeter deformation data is obtained in real time by fusing binocular vision, optical fiber strain and a laser displacement sensor; dynamically outputting a clamp compensation instruction in combination with the finite element stiffness matrix and an XGBoost prediction model; a PSO-Adapt ivePena lty algorithm is introduced to carry out multi-objective optimization, so that the response speed and the cooperation efficiency of the system are improved; and the pneumatic actuating mechanism adopts a double-acting cylinder and a cam-groove mechanism, so that high-precision adjustment is realized. The method has the advantages of high precision, fast response and strong multi-clamp collaboration, and is suitable for the intelligent manufacturing fields of automobiles, aerospace and the like.

The invention discloses a thin-wall structure topological optimization design method, device and system, and a storage medium. The method comprises the following steps: calculating any unit density in a design domain according to a structure topological optimization model; calculating a displacement vector according to the density of any unit in the design domain, the total stiffness matrix and the external load vector; calculating the structural flexibility according to the element stiffness matrix and the displacement vector; according to the unit density and the structural flexibility, obtaining the sensitivity of the target function and the constraint function to design variables; establishing a topological optimization model by taking the minimum structural flexibility as a target function, taking the welding spot area as a constraint condition and taking a design variable as a normalized height; and according to the sensitivity of the target function and the constraint function to the design variables and the topological optimization model, performing updating iteration on the design variables by utilizing an MMA algorithm to obtain an optimized structure. By the adoption of the technical scheme, on the premise that the technological constraint of the superplastic forming technology is met, the structure with the excellent mechanical property is obtained.

The invention provides a direct comprehensive modeling method for a helicopter tail rotor / tail beam coupled substructure, which comprises the following steps of: constructing a blade model, and dispersing the blade model to obtain a mass matrix, a rigidity matrix, a damping matrix and a generalized force vector expression of a single blade; establishing a structural kinetic equation of the tail beam; and finally, according to the displacement boundary condition of the joint of each paddle and the tail beam, converting the paddle structure dynamic equation, and assembling the rigidity matrix, the damping matrix, the mass matrix and the generalized force vector of each paddle after conversion with the rigidity matrix and the mass matrix of the tail beam respectively to obtain the structure dynamic equation of the tail rotor / tail beam coupling system. And establishing a structural dynamic model of the tail rotor / tail beam coupling system. The method is simple and reliable in modeling process and high in universality, is not limited by the distribution type of the tail rotor, can be applied to the non-uniformly distributed tail rotor, and provides a new thought for coupling analysis of the tail rotor / tail rotor and rotor wing / fuselage of the helicopter, dynamic characteristic solving of the tail rotor and analysis of stability.

The invention belongs to the technical field of aerospace, and particularly relates to a modal-based aircraft structure load reconstruction method. The method comprises the following steps: acquiring modal information of a key position of an aircraft structure through a structure finite element model, wherein the modal information comprises a node displacement modal and a unit stress and strain modal matrix; obtaining a node resultant force mode and a profile resultant force / resultant moment mode matrix according to the finite element grid topological relation; and finally, reconstructing the stress / strain intensity of the key position of the structure and the resultant force / resultant moment of the key section from the generalized displacement of the structure according to the modal matrix. The algorithm does not need to process a structural overall rigidity matrix and a damping matrix, and engineering practical application is facilitated.

The invention discloses a welding thermal stress simulation method, device, equipment and medium based on a crystal plasticity finite element, and relates to the technical field of welding thermal stress finite element simulation. The method comprises the steps that a sample is prepared according to a specific multi-phase metal material, and phase distribution and crystal orientation information of a two-dimensional plane of the material are obtained through a metallographic experiment; and a three-dimensional multi-grain model is constructed based on the two-dimensional information. According to the method, a crystal plastic constitutive model is adopted to describe the flowing behavior of the material at high temperature, crystal slippage and polycrystal interaction are considered, the influence on the material performance is reflected from the microstructure evolution level, and the problem that the influence on the macroscopic mechanical performance of a microstructure is difficult to capture in welding multiphase metal material simulation is solved; two-dimensional representation is obtained through a metallographic experiment, the Young modulus and rigidity matrix parameters are accurately calculated by combining forward stretching and shear simulation, the rigidity matrix precision is improved, a temperature field area is divided, stress evolution and residual stress are calculated by combining a thermal-elastic-plastic model, and the welding thermal stress calculation precision is improved.

The invention relates to a joint rotation combined collaborative robot real-time modal analysis method, which comprises the following steps of: 1, splitting a robot into a plurality of independent modules, and enabling each module to be equivalent to a super unit; step 2, obtaining a flexibility matrix Ci and a mass matrix Mi of each super-unit under an output coordinate system of the super-unit, and calculating and converting the Ci to obtain a flexibility matrix CJi of the super-unit under the output coordinate system when the super-unit rotates; 3, the flexibility matrix CJi and the mass matrix Mi obtained in the step 2 are converted to a robot end coordinate system, a robot whole machine flexibility matrix nC and a whole machine mass matrix nM are obtained, and the whole machine rigidity matrix nK is obtained by conducting inversion on nC; and 4, establishing an undamped free vibration equation of the robot, and substituting the complete machine flexibility matrix nC and the complete machine mass matrix nM obtained in the step 3 into the equation so as to solve the inherent frequency of the collaborative robot in real time. According to the method, the rigidity change condition during rotation of the joint module is considered, and the calculation amount is greatly simplified while the calculation error is reduced.

The invention discloses a numerical control machine tool synchronous evolution control method and system associated with dynamic and static errors, relates to the technical field of information processing management, and is used for solving the problem that a machine tool structure optimization method is poor in structural integrity, structural connectivity and dynamic response characteristic analysis. By monitoring and analyzing geometric structure parameter changes of all parts in the machine tool operation process, effective geometric structure parameters with the high influence degree are screened out, preliminary optimization is carried out, a geometric structure optimization evaluation model is established, and an optimization result is evaluated; the method comprises the following steps of: acquiring local rigidity and weight, establishing an optimization evaluation model, defining geometric structure parameters of a plurality of components as an integral assembly structure, constructing a parallel optimization model by utilizing a grid division and rigidity matrix calculation method, and finally obtaining optimization results of a macroscopic unit and a connecting unit by taking minimization of structural flexibility as a target. Key parameters can be accurately monitored and optimized, the structural connectivity is considered, and the overall performance and stability are improved.

The invention relates to a vibration forecasting modeling method for a ring rib cone-column combined shell, which comprises the following steps of: deducing a dynamic stiffness matrix of a conical shell from basic conical shell vibration response solution, degenerating the conical shell into a cylindrical shell and an annular plate by changing a cone vertex angle of the conical shell, and then, carrying out vibration forecasting modeling on the cylindrical shell and the annular plate by taking the conical shell, the annular plate and the cylindrical shell as basic substructures. The method comprises the following steps of: splicing a plurality of substructure shells by utilizing the conditions of displacement continuity and internal force balance on a splicing surface of the combined shell to form an overall dynamic stiffness matrix of the combined shell under a global coordinate system, and forecasting the inherent frequency and vibration response of the combined shell by utilizing the dynamic stiffness matrix.

The invention discloses a cross-domain coupling control method for an air suspension and an active stabilizer bar. The cross-domain coupling control method comprises the steps that a signal input layer collects and fuses data and transmits the data to a decision-making layer; the decision-making layer forms a control instruction based on a model predictive control algorithm, and comprises the steps of constructing an automobile three-degree-of-freedom coupling dynamic model, and iteratively solving a cost function minimum value in a rolling time domain to obtain the control instruction; the three-degree-of-freedom coupling dynamic model quantifies multi-dimensional motion association through a stiffness matrix off-diagonal term, can accurately predict the cross influence of air pressure adjustment of the air suspension on the roll motion, and provides a nonlinear prediction basis for model prediction control. According to the invention, by cooperating with the multi-dimensional dynamic signal and the dynamic arbitration control logic, the complex composite working condition is adapted, and the cooperative optimization of the vertical comfort, the roll stability and the pitching dynamic characteristic of the vehicle is realized.

The invention relates to the technical field of structure optimization, in particular to a topological optimization method and device for a GPU acceleration fiber reinforced composite material structure, and the method comprises the steps: obtaining parameters such as material attribute parameters and design domain size; 21 basic stiffness matrixes are calculated; respectively filtering the density variables and the angle variables; a geometric multi-grid preprocessing conjugate gradient method iteration solver is adopted to calculate the current displacement of each node of the densest grid level; and calculating an objective function according to the current design variable and the node displacement, performing sensitivity analysis on the objective function and the constraint condition to update the density and angle variables, judging whether a topological optimization iteration convergence condition is met or not, and outputting an optimization result if the topological optimization iteration convergence condition is met. Therefore, the problems that the stiffness matrix of each element in the topological optimization problem of the large-scale fiber reinforced composite material structure cannot be stored due to the limited memory of the global memory of the GPU, and the calculation efficiency of the stiffness matrix of the dynamic calculation element in the finite element solving process is low are solved.

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.

The invention provides a thermal elastic structure joint topological optimization method based on MATLAB and ABAQUS, and belongs to the technical field of thermal elastic structure optimization design. Firstly, finite element models of mechanical loads and thermal loads are established in ABAQUS, and files are exported; then calling an ABAQUS operation model in MATLAB, extracting core data such as nodes, units and a stiffness matrix, and constructing a parameterized thermodynamic finite element model based on an SIMP method; calculating a function value and sensitivity by taking volume minimization as a target and taking global stress and temperature constraint as conditions; and finally, iteratively optimizing the design variables by adopting a moving asymptote algorithm, and obtaining a final topological configuration through a filtering method. Through deep cooperation of MATLAB and ABAQUS, core finite element data of commercial software is extracted at a time for optimization iteration, repeated data generation and interaction are avoided, the calculation efficiency is greatly improved, and an efficient solution is provided for processing the topological optimization problem of stress and temperature constraints under complex heat-force loads.

The invention belongs to the field of machining, and discloses a modeling calculation method and system for dynamic rigidity of a cutter handle-main shaft combination part, and the method comprises the following steps: S1, modeling a geometric structure and dynamic displacement of the combination part; s2, performing multi-scale modeling on the contact surface morphology and solving the normal spacing variation of the joint part; s3, joint surface micro-convex body contact characteristic modeling is carried out; s4, modeling the non-linear stiffness of the infinitesimal junction surface; and S5, constructing an integral dynamic stiffness matrix of the joint part. According to the modeling calculation method for the dynamic stiffness of the cutter handle-main shaft combination part, high-precision modeling of the dynamic characteristics of the cutter handle-main shaft combination part is achieved through a step Timoshenko straight beam model and a distributed nonlinear spring layer in combination with a slicing method and a fractal contact theory. The method is suitable for high-precision nonlinear dynamic modeling of a numerical control machine tool, a machining center and the like, and vibration, deformation and stability problems in the machining process can be effectively predicted.

The invention relates to a method for calculating the internal force of a shear pin type sliding friction pendulum support. The method comprises the following steps: acquiring a structure external load, a stiffness matrix, a mass matrix, a shear pin state value and parameters of the shear pin type sliding friction pendulum support; establishing a structure displacement increment iterative formula at the moment t; according to the state value of the shear pin, determining a calculation formula of the internal force and the tangent rigidity of the shear pin type sliding friction pendulum support; substituting the calculation formula of the internal force and the tangent rigidity of the shear pin type sliding friction pendulum support into a structure displacement increment iterative formula at the moment t, and carrying out iterative calculation until the converged internal force of the shear pin type sliding friction pendulum support is calculated; judging whether the state value of the shear pin is updated or not, and determining the internal force of the shear pin sliding friction pendulum support at the moment. The invention provides a shear pin type sliding friction pendulum support internal force calculation method and device, and the method comprises the steps: determining the internal force and tangent stiffness of a support according to the damage state of a shear pin, and simulating the limiting effect on the support when the shear pin is not damaged, and the energy consumption and damping effect of a sliding friction pendulum after the shear pin is damaged.

The invention relates to the technical field of nuclear reactor fuel element analysis, in particular to an irradiated zirconium alloy plasticity limit prediction method based on a crystal plasticity finite element, which comprises the following steps: establishing a three-dimensional polycrystalline representative body cell model conforming to the actual grain size of zirconium alloy; based on a crystal plasticity theoretical model, zirconium alloy material parameters are obtained through calculation; boundary conditions and load conditions are determined, finite element calculation is executed in combination with material parameters, and an element stiffness matrix of each increment step is output; assembling the unit stiffness matrix, and obtaining a macroscopic stress-strain matrix of the three-dimensional polycrystal cell model through a homogenization method; and substituting the macroscopic stress-strain matrix into the Rice theoretical criterion, traversing the macroscopic stress-strain matrix of each increment step, and determining the plastic strain meeting the judgment critical condition. According to the method, accurate finite element plastic limit analysis can be carried out on the irradiation material, and the plastic limit strain of the zirconium alloy under the irradiation condition can be accurately judged.

The invention discloses a space truss internal force monitoring method, device and equipment based on three-dimensional reconstruction, and the method comprises the steps: obtaining an initial state space truss three-dimensional reconstruction model and a current state space truss three-dimensional reconstruction model, and obtaining a three-dimensional reconstruction model alignment model between the initial state space truss three-dimensional reconstruction model and the current state space truss three-dimensional reconstruction model based on a truss model alignment strategy; and determining the current deformation amount and the current net rack overall rigidity matrix corresponding to each spherical node, and determining a stress analysis result, an internal force analysis result and a balance verification result. According to the embodiment of the invention, the three-dimensional reconstruction models corresponding to the space truss in the initial state and the current state can be obtained based on image acquisition and three-dimensional reconstruction, and the current deformation of the spherical node and the current truss overall stiffness matrix are determined by combining the two three-dimensional reconstruction models. The stress analysis result, the internal force analysis result and the balance verification result are obtained through analysis, a strain gauge does not need to be attached to the ball node, the construction cost is reduced, and the efficiency and accuracy of obtaining the space truss internal force monitoring related result are improved.

The invention discloses a multi-scale structural stiffness optimization design method based on neural network re-parameterization, which comprises the following steps: microstructure parameterization modeling: carrying out parameterization modeling on a microstructure by adopting a level set method, and controlling the volume fraction and geometric configuration of the microstructure by adjusting a cutting height parameter; proxy model construction: establishing a mapping relation between cutting height parameters and microstructure equivalent mechanical properties by using a neural network to form a high-precision proxy model; neural network re-parameterization design: constructing a neural network optimizer, taking coordinates of each discrete unit in a design domain as input, and outputting corresponding cutting height parameters; neural network parameters are updated through automatic differentiation and back propagation, and continuous optimization of design variables is achieved; and a multi-scale topological optimization process: calculating a global stiffness matrix and structural flexibility in combination with an agent model and finite element analysis, and obtaining an optimal multi-scale structural topology meeting volume constraints through loss function minimization iterative optimization.

The invention discloses a wing structure multi-level modeling method, device, equipment and medium, and relates to the field of structure modeling simulation and wing structure analysis, and the method comprises the steps: decomposing a target wing into a 0-level simplified beam model, a 1-level unit cell model and a 2-level sub-model; performing order reduction analysis on the 1-level unit cell model, constructing an equivalent section attribute matrix, and establishing a wing simplified model matched with the beam element finite element stiffness matrix; building a sub-model simulation database based on multi-working-condition simulation, applying a generalized load and a typical external load, and obtaining displacement field data under each working condition; according to the displacement field data, extracting a displacement field boundary condition and a POD coefficient of the stress field data, and constructing a data driving sub-model; and performing multi-level model analysis on the target wing according to the wing simplified model and the data driving sub-model. The mechanical property and response of the wing structure under different working conditions can be efficiently and accurately simulated and analyzed.

The invention relates to the technical field of constructional engineering, in particular to a method for calculating the bearing capacity of a large-span concrete-filled steel tube arch. Comprising the steps that S1, the concrete-filled steel tube arch is divided into a plurality of concrete-filled steel tube beam units and subunits; s2, acquiring a stiffness matrix of the concrete-filled steel tube beam unit; s3, applying a reference load to the concrete-filled steel tube beam unit, and calculating node pure deformation displacement of the concrete-filled steel tube beam unit under the structural coordinate system; s4, establishing a co-rotation coordinate system, and calculating a stress vector of each subunit under the co-rotation coordinate system; s5, calculating rod end resistance and unbalanced force of the concrete filled steel tube beam unit; and S6, whether the unbalanced force meets the convergence requirement or not and meets the material damage standard or not is judged, and when the conditions are met, the corresponding applied load is output to serve as the ultimate bearing capacity. According to the method for calculating the bearing capacity of the large-span concrete-filled steel tube arch, the calculation workload is greatly reduced in a mode of degree-of-freedom condensation and co-rotation coordinate system conversion, and an accurate and efficient algorithm is provided.

The invention discloses a circumferential contour prediction method based on cutting force and deformation field space-time correlation, and relates to the field of aerospace, and the method comprises the following steps: 1, carrying out the spatial discretization of a circumferential contour region of a target workpiece; step 2, establishing a lightweight structure stiffness matrix; 3, constructing an elastic mechanism model and solving delta-F mapping; 4, introducing the time sequence correlation of the cutting load into the elastic mechanism model; step 5, constructing a Boolean relationship between the tool path and the workpiece envelope; step 6, fusing actual measurement process signals, and performing state correction; step 7, iterating the elastic model again by using the corrected load; and step 8, reconstructing full-field deformation based on spatial correlation. According to the method, online prediction of the station-level circumferential deformation field is achieved, the method can be used in the multi-procedure machining process, deformation in-situ compensation of the procedure is achieved, a clamping positioning strategy of the next procedure is output, and the manufacturing quality and the production efficiency are improved.

The invention relates to the technical field of structure optimization, in particular to a topological optimization method and device for a large-scale fiber reinforced composite material structure, and the method comprises the steps: obtaining material attribute parameters and the like; calculating a unit stiffness matrix corresponding to each group of sampling angles according to a preset sampling interval and attribute parameters of a preset fiber reinforced composite material, calculating a template stiffness matrix of each grid level, and calculating the current displacement of each node of the densest grid level by adopting a geometric multi-grid preprocessing conjugate gradient method; and calculating a target function according to the current design variable and the current displacement of each node of the densest grid level, so as to update the design variable until a preset number of iterations is reached, and outputting a new optimization design. Therefore, the problems that due to the fact that the memory of a GPU global memory is limited, the element stiffness matrix cannot be stored in the topological optimization problem of the large-scale fiber reinforced composite material structure, and the calculation efficiency of the dynamic calculation element stiffness matrix in the finite element solving process is low are solved.

The present invention belongs to the field of composite material mechanics technology and provides a method and system for predicting the hole extrusion strength of ceramic-matrix composite parts. The method comprises: meshing a finite element geometric model of the ceramic-matrix composite part to be tested; obtaining the stress field of each mesh element through finite element simulation; based on the stress field, using the three-dimensional Hashin criterion or the MMF3 criterion to determine the type of mesh element damage and perform stiffness degradation to obtain a stiffness matrix; using the stiffness matrix and the applied displacement load to obtain the current force load, and then obtaining the hole extrusion strength based on the current force load and the hole contact area. The method of the present invention can accurately predict the hole extrusion strength of a part, laying the foundation for mechanical connection performance analysis of composite materials and high-fidelity simulation calculations of composite structures.