47 results about "Limit load" patented technology

The invention discloses a shield segment heterogeneous modeling crack and limit simulation method. The method comprises the following steps: constructing an aggregate three-dimensional model database; generating a heterogeneous aggregate accumulation model; establishing a concrete shield segment three-dimensional model; defining a model material constitutive relation and a damage criterion; setting an equivalent field staged loading working condition and a boundary condition; grid division and nonlinear static simulation solution are carried out; and constructing a crack response monitoring and output module, and executing judgment of a structure limit state. High-precision construction and multi-stage loading simulation of a shield segment model are realized by reconstructing a concrete microstructure and steel bar arrangement information and combining a field loading force value and a boundary condition; and a nonlinear material constitutive and damage evolution criterion is introduced, the whole-process response of the crack is captured, a limit state criterion is set, and automatic identification and damage form judgment of the bending resistance limit load are completed. According to the method, a technical path capable of being popularized is provided for shield segment structure performance evaluation, ultimate bearing prediction and a crack control strategy.

The invention discloses a method for dynamically evaluating the ultimate bearing capacity of a layered damage composite material cylindrical pressure-resistant shell in the field of deep sea equipment structure health monitoring, which comprises the following steps of: establishing a nonlinear relationship between a critical buckling load of an unlayered composite material cylindrical shell and a critical buckling load of a layered composite material cylindrical shell, and calculating an attenuation coefficient of each group of samples; measuring inner and outer layer strain values of the to-be-evaluated composite cylindrical shell, detecting extreme value statistics and cumulative sum based on change points of the inner and outer strain values, judging that the position of the point is layered, constructing a layering point set, calculating five layering characteristic parameters of the to-be-evaluated composite cylindrical shell based on the layering point set, and substituting the five layering characteristic parameters into an attenuation coefficient formula, obtaining a critical load of the to-be-evaluated composite cylindrical shell; according to the method, through combination of dual-surface strain cooperative monitoring and a regression model, prediction of critical buckling loads in a service state is realized, environments such as shell thickness fluctuation, salt spray corrosion, interface fracture parameter measurement errors and impact loads are compatible, strain gauge monitoring and limit load online evaluation are fused, and a dual evaluation system is formed.

The invention relates to the field of steel member engineering, in particular to a high-strength steel combined multi-chamber box-section bent steel member and a manufacturing method thereof, and the manufacturing method comprises the following specific steps: S1, obtaining the design form of the steel member; s2, preparing an outer side chamber of the steel member; s3, prestress is applied to the outer side chamber in the axial direction of the outer side chamber so that the outer side chamber can be bent to a first form, a first eccentric value of the first form is obtained, and the first eccentric value is larger than the designed eccentric value; s4, top pressure towards the inner side of the bend is applied to the first form to a second form, the second form is in a pre-tightening state, a second eccentric value of the second form is obtained, and the second eccentric value is smaller than the designed eccentric value; s5, the outer side chamber is kept in the second form, and the matched inner side chamber is welded to obtain the steel member; and S6, after the force is unloaded, the inner side chamber is subjected to pre-tensile stress, the outer side chamber is subjected to pre-compressive stress, and the steel member is obtained. Pre-tensile stress is applied to the inner side of the steel member, pre-compressive stress is applied to the outer side of the steel member, and therefore the axial compression buckling ultimate load of the bent steel member is increased.

The invention discloses a deep foundation bearing capacity characteristic value calculation method and system based on data fusion. The method comprises the steps that data collection is completed through a deep load test, and a load settlement curve and a settlement time logarithmic curve are formed; generating a smooth curve; identifying a slope mutation point of the curve by adopting a first-order derivative mutation method, wherein a load corresponding to the mutation point is a proportional limit load; if the slope abrupt change point is not recognized, the curve is set as a slowly changing curve; extracting the slope and the slope change rate of the curve under each level of load, and completing the judgment and correction of the limit load by fusing the multi-dimensional data of the two curves and combining preset thresholds including the settlement amount and the settlement stabilization time; and further calculating the bearing capacity characteristic value of the deep foundation by combining the numerical relationship between the ultimate load and the proportional limit load.

The invention discloses a shield butt joint section curtain grouting additional load determination method, and relates to the technical field of geotechnical engineering grouting, and the method comprises the steps: carrying out the preprocessing of obtained grouting measurement data, obtaining an envelope point set, and carrying out the fitting optimization based on an envelope line function model, and obtaining an optimized envelope line function; calculating an ultimate load, attenuating the ultimate load to a preset engineering allowable threshold value to obtain an ultimate load acting distance, and determining boundary conditions through an envelope line intercept analysis method; and correcting the limit load according to a preset grouting load safety coefficient to obtain a corrected limit load, and performing inversion correction in combination with the grouting measurement data to obtain a final limit load and a final boundary condition. According to the method, the significant action range and the most unfavorable load condition of the grouting load are determined by capturing the spatial distribution and evolution law of the additional soil pressure field caused by grouting, and accurate load boundary conditions are provided for model analysis or finite element calculation.

The invention provides a method, a system and equipment for evaluating fatigue performance of an inner ring rib steel pipe concrete joint. The method comprises the following steps: calculating structural geometric parameters of the jacket foundation according to an ultimate load condition; obtaining a fatigue load time history curve through load simulation based on the parameters; a node hot spot stress cycle amplitude is obtained through finite element analysis; and finally, calculating fatigue accumulated damage through an S-N curve specially fitted for the inner ring rib steel pipe concrete node, and performing evaluation. The method can solve the technical problems that an existing fatigue evaluation method does not consider the specific structure, material and process characteristics of the inner ring rib steel pipe concrete joint, so that the evaluation result discreteness is large, the accuracy is insufficient, and the requirement for accurate evaluation of the fatigue life of the complex space joint of the offshore wind turbine generator is difficult to meet.

The invention relates to the technical field of metal structure stability finite element analysis, in particular to a stability limit load calculation method based on a dichotomy and a computer program product, and the method comprises the steps: carrying out the structural modeling of a target structural part, completing the finite element pretreatment, applying an initial load to a modeled structure, obtaining an initial maximum Mises stress value of the structure, and calculating the stability limit load of the target structural part. According to the elastic field linear superposition principle and the stability upper limit principle, the initial load range [Flower, Fupper] of the stability limit load is calculated, then the load range is iteratively updated by adopting a dichotomy method until the convergence condition is met, the final stability limit load is obtained, the total calculation frequency is reduced by 40%-60%, and the final stability limit load is obtained. Meanwhile, full-process automation from load setting to result judgment is achieved, and the requirement for manual intervention is remarkably reduced.

The application discloses a kind of based on digital-analog collaborative driving's dynamic stress field identification method of steel-concrete transition zone of mixed tower wind turbine unit, comprising: creating macroscopic wind turbine cabin mixed tower foundation coupling dynamics numerical analysis model, the calculated displacement of steel-concrete transition zone of mixed tower wind turbine unit multibody dynamics analysis model under the action load of shutdown operating condition is obtained;In the steel-concrete connection transition section of mixed tower wind turbine tower drum, the complementary layout of displacement sensor and accelerometer of LVDT electromagnetic induction principle is designed, and the predicted displacement is obtained;The contact stiffness and interface friction coefficient of the contact element of steel-concrete transition zone microscopic slip and debonding behavior of wind turbine multibody dynamics analysis model are inverted, and the dynamic stress field of steel-concrete transition zone under the action of tower top limit load is calculated.The application realizes the cross-scale perception of steel-concrete interface complex stress field and the real-time early warning of hidden damage by heterogeneous sensor network, nonlinear multibody dynamics modeling and data model two-way coupling mechanism.

The present application relates to the field of nondestructive testing, and provides a composite laminated sheet interlaminar damage identification and failure determination method, comprising: collecting acoustic emission signals of a composite laminated sheet in a short beam shear test, and extracting amplitude intensity and peak frequency; classifying and identifying damage categories in an interlaminar shear failure process; calculating a relative cumulative count of acoustic emission signals of each damage, and synchronously calculating a load change increment, and constructing a relationship curve of both and time; determining a damage starting time according to an initial change feature point of the relationship curve relative to the cumulative count curve, and cooperatively determining an interlaminar shear failure point in combination with a mutation feature of the load increment curve, and outputting a failure point load value as a limit load of interlaminar shear strength. The present application also provides a device, equipment and medium applying the method. The present application effectively identifies damage modes and determines an interlaminar shear failure starting point, and accurately determines a shear strength of a laminated sheet.

The invention belongs to the technical field of aircraft structural strength analysis, and particularly relates to a metal material stress plasticity correction method. The method comprises the steps that firstly, material parameters of the aircraft metal material structure are obtained; step 2, adopting a linear finite element static strength analysis method to obtain stress distribution of the aircraft metal material structure under the action of a limit load, and if the stress meets a preset condition, entering step 3; 3, according to the material parameters, the Ramberg-Osgood nonlinear hardening index during tensile failure is corrected, and the corrected nonlinear hardening index is obtained; and 4, constructing a stress equation, and substituting the nonlinear hardening index into the stress equation to obtain the real stress of the aircraft metal material structure after plastic correction. According to the method, the metal material stress of the aircraft metal material structure can be conveniently and quickly subjected to plastic correction.

The application discloses a kind of local reinforcement selected area laser melting deposition high-strength titanium alloy preparation method and system, belong to additive manufacturing technical field.The local reinforcement selected area laser melting deposition high-strength titanium alloy preparation method provided by the application, by establishing target titanium alloy structure three-dimensional model and carrying out finite element limit load simulation analysis, stress distribution and potential dangerous area are identified;Based on the analysis result, the performance requirement is divided, the material enhanced local area is determined, and the laser scanning path and powder feeder movement trajectory are planned;Path file is imported into composite equipment to set process parameters;Titanium-based composite material powder is selectively laid in the enhanced area, and a locally reinforced structure is obtained by selective laser melting.The scheme realizes the spatial selective distribution of powder composition, forms a uniform distribution of high-stress areas, significantly improves the local strength and maintains the overall strength and plasticity matching, effectively solves the problem of insufficient performance matching of titanium alloy components under complex load.

The invention discloses an aerospace equipment structure limit load inversion method based on historical maintenance data, and belongs to the related technical field of digital twinning. The method comprises the following steps: firstly, counting historical maintenance data of aerospace equipment, extracting and fitting the number of cycles of a target structure from service to damage, and determining the statistical life of the target structure; secondly, establishing a finite element model according to the actual loading condition of the target structure, and applying a load to obtain a stress field and a strain field of the target structure; thirdly, a fatigue prediction life calculation model based on the stress field and the strain field is established, and the fatigue prediction life is obtained. And finally, carrying out parameter optimization by taking the load as an optimization variable and taking an absolute value of a difference value between the minimum fatigue prediction life and the statistical life as an optimization target to obtain a limit load inversion result. According to the method, the most matched limit load amplitude is iteratively optimized by fully utilizing historical maintenance data and utilizing an optimization method, and powerful support can be provided for further operation maintenance, optimization design and the like of the structure.

The invention discloses a mechanical measuring instrument overrun protection mechanism with a self-recovery function and a debugging method thereof, and relates to the technical field of mechanical measuring instruments. The over-limit protection mechanism comprises a fixed connecting part, a floating part, an elastic deformation part and an overload limiting part; the fixed connecting part and the floating part are connected with the elastic deformation part to form a quadrilateral structure, the floating part always moves parallel to the fixed connecting part when bearing a tested load force, and a gap is reserved between the overload limiting part and the floating part and is used for limiting overload displacement of the floating part; when the floating part is stressed and deformed to a limit position, the floating part is in contact with the overload limiting part to limit further displacement of the floating part, so that the force transmitted to the measuring instrument is not increased any more; and after the over-limit load is unloaded, the elastic deformation part automatically resets, so that the clearance between the floating part and the overload limiting part is recovered. According to the over-limit protection mechanism, elastic deformation without frictional resistance can be achieved on the premise that parallel deformation guiding is achieved, over-limit protection is achieved in cooperation with a fixed limiting mechanism, and normal work can be automatically recovered after over-limit force is unloaded.

The invention relates to an analysis and calculation method for a blade root connection structure of a wind driven generator, and the method comprises the steps: constructing a finite element model for coupling a blade shell unit and a blade root entity unit, and defining the material attributes of all parts; and a coupling connection relation between the blade shell unit and the blade root entity unit is set to simulate a real force transmission path. Then, target pre-tightening force is applied to the connecting bolts and locked, and distributed working loads are applied to the blade shell units at different angles in the pre-tightening state, so that the bending moment of the end of the blade root is larger than the limit load at the angle. And solving and calculating the loaded model, extracting stress data for connecting the bolt and the bolt sleeve, and performing strength and fatigue analysis on the bolt and the bolt sleeve based on the data. According to the method, the accuracy of stress calculation of the blade root connecting structure and the model precision are remarkably improved by introducing the geometric characteristics, the rigidity characteristics and the distributed load transmission path of the real blade, so that more reliable guidance is provided for design of the wind power blade root and the connecting structure.

The invention provides a method and device for determining a jacking of a full framing, a storage medium, computer equipment and a program product. The method comprises the steps that the rotational rigidity of a top node in the full framing and the actual jacking load of the full framing are obtained; initial structure parameters of the candidate jacking are determined; circularly executing the following steps to adjust the structural parameters of the candidate jacking until the candidate jacking meets the design requirements: acquiring the bending line rigidity of the candidate jacking; on the basis of a preset mathematical model, the length coefficient of the candidate jacking is calculated according to the rotational rigidity and the bending line rigidity, and the preset mathematical model is obtained through analysis on the basis of an energy method under the condition that the semi-rigidity of the top node is considered; determining the stability limit load of the candidate jacking according to the length coefficient and the bending line rigidity; according to the stable limit load and the actual jacking load, whether the candidate jacking meets the design requirement or not is determined; and if not, modifying the structural parameters of the candidate jacking, and returning to the step of acquiring the bending line rigidity of the candidate jacking.

The application belongs to the field of fatigue life calculation, and particularly relates to a wheel disc crack propagation life calculation method based on a stress intensity factor critical value. The method comprises the following steps: obtaining stress or strain distribution of the wheel disc under a limit load working condition; pre-preparing an initial crack at a feature part of the wheel disc, and calculating a stress intensity factor distribution curve of a crack front under the limit load working condition; according to a first crack propagation plan, terminating the propagation when the stress intensity factor of the crack front reaches a material fracture toughness Kc, and obtaining a crack propagation morphology and a stress intensity factor distribution curve; obtaining stress or strain distribution of the wheel disc under a type I cyclic peak load working condition; calculating a maximum stress intensity factor K C ′ corresponding to the crack propagation morphology under the type I cyclic peak load working condition; and taking the maximum stress intensity factor K C ′ as a crack termination propagation condition, and calculating a crack propagation life. The crack propagation life is more conservative and has higher safety.

Method for damping loads acting on a loading unit (100) for transporting transport elements (103) in an overload case to protect against damage, wherein measured values ​​(62) about the current state of the loading unit (100) are recorded by a sensor device (61) and wherein at least one damping device (2) is controlled by the measured values ​​(62), characterized by that a shearing device (42) is provided on the loading unit (100) which shears off when the load acting on the loading unit (100) exceeds a predetermined level (66), and that a control device (48) detects an overload case (63) from the recorded measured values ​​(62) when a shear sensor (67) detects shearing of the shear device (42), and that the damping of the damping device (2) is set to a predetermined high value at least immediately after the detection of the overload case (63), and the damping set to a high value is maintained for a predetermined time period (67) after the detection of an overload case (63), and the damping is reduced to a lower damping (71) after the predetermined time period (67) in order to initially increase the load on transport elements (103) transported on the loading unit (100) up to a predetermined limit load (64) and then reduce it after the predetermined time period (67).

The invention discloses a method and system for evaluating the failure state of a hydrogen conveying pipeline. The method comprises the steps that the hydrogen enrichment concentration of the hydrogen conveying pipeline to be evaluated is determined; the limit load of the current pipeline under the hydrogen-containing condition is calculated according to parameters such as the hydrogen enrichment concentration, the pipeline structure size, the pipe mechanical property and the crack shape size; according to the limit load, constructing a failure evaluation curve of the current hydrogen pipeline containing the cracks, and calculating to obtain a dimensionless load factor and a dimensionless stress intensity factor required by current evaluation; and according to the dimensionless load factor and the dimensionless stress intensity factor, determining the safety state of the current hydrogen conveying pipeline by using the failure evaluation curve.

The invention relates to the technical field of hot isostatic pressing equipment design and manufacturing, and discloses a buckling failure judgment method of a prestressed steel wire winding core cylinder for hot isostatic pressing equipment, which comprises the following steps: acquiring basic information of a target core cylinder; determining an inner cylinder radius deformation value caused by winding operation of the target core cylinder under the pre-tightening working condition; equivalent external pressure borne by the outer wall of the outer cylinder under the winding effect is obtained; determining a plurality of comprehensive influence coefficients for correcting the buckling limit based on physical and geometric characteristics between the inner cylinder and the outer cylinder; the structure parameters, the material parameters and the multiple comprehensive influence coefficients are combined, a limit state equation of the core cylinder is established, and the buckling limit load of the target core cylinder without instability under the action of prestressed steel wire winding is calculated; and calculating the ratio of the buckling limit load to the equivalent external pressure, comparing the ratio with a preset safety coefficient, and judging whether the target core cylinder is subjected to buckling failure or not. According to the method, accurate evaluation of the buckling failure of the double-layer cylinder wall core cylinder structure for the hot isostatic pressing equipment is realized.

The application discloses a kind of core column plate fast design system and method based on finite element parameter regression.Firstly, ABAQUS is combined with concrete damage plastic model, and a multidimensional parameterized finite element-experience formula database is established, and the function relationship of limit load, stiffness degradation and unit volume bearing capacity and key parameters is obtained by regression.On this basis, database and regression model are called, and multi-objective optimization that satisfies bearing capacity, stiffness and self-weight / hollow ratio constraint simultaneously is carried out, and the optimal combination parameters such as UHPC strength grade, upper and lower plate thickness, tensile reinforcement ratio, core column diameter and spacing and rib width are quickly deduced back, and reinforcement drawing and checking report are automatically generated.The application preposes tedious single finite element analysis as reusable parameter library, realizes the engineering fast design of core column plate, and is conducive to the popularization and application of the new plate system.

The application discloses a high ground stress tunnel reserved deformation amount determination method, system, medium and product, relates to the tunnel excavation construction technical field, and the method comprises the following steps: determining the inner and outer boundaries of a surrounding rock bearing arch structure based on tunnel engineering geological conditions and construction factors; constructing a mechanical analysis model of the surrounding rock bearing arch structure based on the inner and outer boundaries of the surrounding rock bearing arch structure; determining the limit load of the surrounding rock bearing arch structure through a simulation experiment based on the mechanical analysis model of the surrounding rock bearing arch structure; and determining the reserved deformation amount of the surrounding rock arch structure based on the mechanical analysis model of the surrounding rock bearing arch structure and the limit load. The application can accurately predict the reserved deformation amount of a high ground stress tunnel and reduce material waste.

The application discloses a design method of pile-column integrated short pile based on deformation and bearing capacity control, determines various working load conditions; judges whether to adopt a pile cap according to site soil layer conditions and pile top deformation control requirements, considers whether to reduce additional load coefficient; determines pile diameter according to engineering actual conditions; calculates foundation part deformation limit value according to pile diameter, load under normal working conditions and column top deformation control requirements; initially determines pile length, respectively calculates pile body internal force and horizontal deformation under normal working conditions and limit load conditions; checks foundation horizontal deformation under normal working conditions, checks foundation horizontal residual deformation under limit load conditions, foundation horizontal bearing capacity under limit load conditions, foundation torsional deformation under normal working conditions and foundation torsional bearing capacity under limit load conditions; determines pile type according to pile bending moment and pile crack resistance bending moment, and the crack resistance bending moment should consider the influence coefficient of horizontal-torsional load coupling effect. The calculation result of the application is reliable and meets design requirements.

The application discloses a kind of steel pipe unloading platform with overweight control belt and use method, belong to steel pipe unloading platform technical field.It includes unloading platform, the top end of the unloading platform is inserted with overweight control belt, one end of overweight control belt is fixed with limit load identification end, the other end of overweight control belt is movably connected with control end, and signboard is arranged on limit load identification end and control end.The application solves the problem of low safety factor of existing unloading platform, sets the second steel pipe between the first steel pipe, connects the third steel pipe between each group of first steel pipe to form the unloading platform, reduces the production cost;limit load identification end is inserted at the top of first steel pipe, if 6 meters steel pipe is stacked, 6 meters control end is inserted into the top of another first steel pipe, and so on;if the steel pipe is flush with the horizontal line of first steel pipe, it means that the weight of steel pipe is equal to the load limit, if it exceeds the horizontal line, it is opposite, and the safety factor of unloading platform use is improved.

The application discloses a kind of wind generating set single blade dead limit load reduction control method and system, when the blade angle setting value of single blade and the actual blade angle measurement value deviation is greater than a certain threshold and the variable pitch rate of the blade is less than a certain threshold, trigger single blade dead fault, enter dead pitch shutdown mode, during shutdown process, first reduce generator speed setting value, make generator speed drop according to preset rate, at this time, blade is controlled by variable pitch PI, simultaneously control generator torque, when generator speed drops to a certain threshold, then according to preset rate, pitch-in shutdown is carried out.The application reduces generator speed setting value, controls the variable pitch of non-dead blade and generator torque, reduces the limit load of each component of unit, to improve the safety of unit, reduce the design cost of unit.

The invention discloses an optimal design method and system for an offshore wind power floating foundation structure, and belongs to the field of ocean engineering structure design, and the method comprises the following steps: S1, building a three-dimensional finite element model of the floating foundation structure, and defining a design domain, a non-design domain, material attributes, volume ratio constraints and limit load working conditions for the three-dimensional finite element model; and S2, independently performing finite element solution for each limit load working condition, and calculating the flexibility sensitivity of each unit in the design domain, so that the overall performance and robustness of the final topological configuration are remarkably improved, the sensitivity of a high-conflict region is actively inhibited, and the reliability of the topological configuration is improved. The optimization process can avoid invalid swing between mutually contradictory rigidity requirements, so that a real global optimal solution can be explored and converged, unprecedented design insight and controllability are provided for design engineers, and convergence stagnation or divergence caused by target conflicts is effectively avoided.

The invention provides a ball linear guide rail pair limit load calculation method, which comprises the following steps of: 1, establishing a ball-raceway displacement coordination equation of a ball linear guide rail pair, and calculating ball-raceway contact deformation and an actual contact angle under the action of vertical displacement of a sliding block; 2, establishing a relational expression of ball-raceway contact deformation and contact force of the ball linear guide rail pair, and calculating ball-raceway Hertz contact force of the linear guide rail pair; and 3, deducing a limit load calculation formula of the ball linear guide rail pair, and calculating the limit load of the ball linear guide rail pair. By the adoption of the method for calculating the limit load of the ball linear guide rail pair, the limit load of the ball linear guide rail pair can be conveniently calculated, a theoretical method is provided for forward design of the ball linear guide rail pair, and a technical means is provided for model selection of the ball linear guide rail pair in the mechanical product design process; and the method has important significance on the technical progress of pushing the rolling linear guide rail.

The application discloses a spaceflight equipment structure limit load inversion method based on historical maintenance data and belongs to the technical field of digital twinning. First, historical maintenance data of spaceflight equipment is counted, the cycle number experienced by a target structure from service to damage is extracted and fitted, and the statistical life of the target structure is determined. Second, a finite element model is established according to the actual load condition of the target structure, and a stress field and a strain field of the target structure are obtained by applying a load. Third, a fatigue prediction life calculation model based on the stress field and the strain field is established, and the fatigue prediction life is obtained. Finally, the load is taken as an optimization variable, the absolute value of the difference between the fatigue prediction life and the statistical life is taken as an optimization target, parameter optimization is carried out, and the limit load inversion result is obtained. The application can provide strong support for further operation and maintenance and optimized design of the structure by fully utilizing historical maintenance data and iteratively optimizing the most matched limit load amplitude by using an optimization method.

The application discloses a pile foundation testing method, which comprises steps S1-S4: S1: loading is applied to the pile foundation by using an anchor pile counterforce device, and the settlement displacement of the pile foundation is detected by using a sensor; S2: within a preset time, when the settlement of the pile foundation is less than a first preset value, the pile foundation is qualified, and step S3 is performed; when the settlement of the pile foundation is greater than the first preset value, the pile foundation is unqualified, and step S4 is performed; S3: the load applied by the anchor pile counterforce device is gradually increased, the settlement displacement of the pile foundation is detected by using the sensor, and the load is increased to the estimated limit load of the pile foundation, and step S4 is performed; S4: after the last level of load is completed, the load applied by the anchor pile counterforce device is gradually reduced until the load is zero. The pile foundation testing method has the advantages of accurate testing result and small testing error.

The invention belongs to the technical field of welding structure strength analysis and safety evaluation, and particularly relates to a welding seam strength accurate evaluation method for machine tool body hoisting analysis. The method comprises the steps that a machine tool body assembly model is preprocessed, a welding part model is established, a welding seam stress concentration area is identified through integral hoisting working condition analysis, and a primary model is established; the welding seam hot spot stress is calculated through a linear extrapolation method based on the IIW criterion; a sub-model is further established, bilinear material parameters are introduced, an elastic limit load and a plastic limit load are calculated through finite element analysis, and then a plastic notch coefficient Kp is obtained; calculating a section coefficient npl and the static strength of the welding seam in combination with an FKM criterion; finally, the static strength utilization rate is calculated according to the total safety coefficient, the hot spot stress and the static strength, and accurate evaluation of the static strength of the welding seam under the hoisting working condition is achieved. According to the method, accurate evaluation of the static strength of the welding seam is achieved, and evaluation deviation caused by simplified hypothesis in a traditional method is effectively avoided.

The invention relates to the technical field of topological optimization, in particular to a topological optimization anti-buckling structure design method and system for a hollow variable cross-section plunger rod. The method comprises the following steps: acquiring telescopic data of a plunger rod; determining a maximum activity stroke based on the scaling data; the buckling danger degree is judged through the maximum movement stroke; detecting inertia moment distribution of the variable cross section according to the buckling danger degree; evaluating the pressure rod stability of the plunger rod by using the inertia moment distribution; an anti-buckling structure is designed according to the stability of the pressing rod and the buckling danger degree; a buckling limit load is simulated based on the anti-buckling structure, and the breaking strength of the material under the buckling limit load is detected; detecting a groove surface crack by utilizing the breaking strength of the material, and marking the position of the groove surface crack; and performing multi-stage material strengthening treatment on the crack position of the groove surface to generate multi-stage material data. Based on the topological optimization technology, the anti-buckling stability of the plunger rod is improved, the service life of the plunger rod is prolonged, and the structural safety and reliability are improved.