20 results about "Limit load" patented technology

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 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 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 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.

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 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 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 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.

The application belongs to the technical field of building anti-collapse, and particularly relates to a method for obtaining a limit stability performance curve of a concrete structure and application thereof. The method comprises: taking limit loads of different concrete structures as training samples, training a first neural network model to obtain a limit load prediction model; determining a stable load range based on the limit load; then taking performance curves constituted by different loads and corresponding column top limit displacements of different concrete structures under different column removal conditions within the stable load range of the concrete structures as training samples, training a second neural network model to obtain a performance curve prediction model; after the limit load prediction model predicts the limit load of a to-be-predicted concrete structure, the performance curve prediction model outputs the performance curve of the to-be-predicted concrete structure according to the to-be-predicted concrete structure and the corresponding limit load. The application can efficiently and accurately obtain the limit stability performance curve of the concrete structure.

The application provides an ice load prediction method, device and electronic equipment for a structure icebreaking process, and belongs to the technical field of ice load prediction. The method comprises the following steps: obtaining size parameters and material parameters of a target ice layer, wherein the material parameters comprise a bending strength; calculating a target stress of a target point on the target ice layer according to a to-be-determined load, a current concentrated load action point coordinate and the size parameters, wherein the target stress is represented by the to-be-determined load; determining an equivalent stress of the target ice layer according to the target stress and the material parameters, wherein the equivalent stress is represented by the to-be-determined load; and predicting the to-be-determined load according to the bending strength and the equivalent stress. The ice load prediction method for the structure icebreaking process provided by the application solves the technical problem in the related art that the ice load prediction method for the structure icebreaking process cannot accurately predict the limit load of any point of the ice layer.

The invention relates to the technical field of advanced steel and iron materials, and provides a prestressed steel strand bond strength prediction method which comprises the following steps: acquiring design parameters of target ground anchor cement paste and a steel strand, and sequentially constructing a compressive strength model, a limit stress model, a stress attenuation model, an interface contact model, a single-branch limit load model, a branch reduction model and a total limit load model. The predicted bond strength is obtained by combining the total limit load and the interface contact area; according to the method, the nonlinear reduction effect of the number of the prestressed steel strands on the bond strength is quantified, the correlation between the number of the prestressed steel strands in the anchor group system and the reduction of the bond strength of a single support is defined, and the problem that in the prior art, the single anchor stress field rule is directly migrated to the anchor group system, and the multi-support interference influence cannot be accurately evaluated is solved.

The invention relates to an assembly (100) comprising a circular disk (160), an annular body (110), and an elastomer ring (190). The annular body (110) has a disk receptacle (120) surrounded by a peripheral lateral surface, which lateral surface has an annular outer groove (130), which is delimited in a first axial direction by a first outer shoulder (132) and in an opposite second axial direction by a second outer shoulder (134). A guide surface adjoins the first outer shoulder in the first axial direction, the radius of which increases monotonically with increasing distance from the first shoulder, and in the case of which dr / dz < 2 / 3, in particular dr / dz < 1 / 3, where r is the radius and z is the axial coordinate of the guide surface in cylindrical coordinates. The circular disk (160) has an outer lateral surface, which has a peripheral inner groove (170) extending radially inwards, which is delimited in the first axial direction by a first inner shoulder (172) and in the second axial direction by a second inner shoulder (174). At least the two aforementioned inner shoulders have a convex profile when viewed in an axial longitudinal section, in which the rotational axis of the circular disk (160) extends. The elastomer ring (190) is clamped between the two aforementioned inner shoulders and the two aforementioned outer shoulders, thereby preventing, in particular, the circular disk from slipping out of the annular body up to a limit load.

The invention discloses a method for monitoring the running state of a wind power blade, relates to the technical field of monitoring and testing of a wind turbine, and aims to solve the problems of false alarm and missing alarm caused by sudden increase of environmental noise and submerging of damage characteristics during a strong wind extreme event. A physical damage feature dictionary constraint signal can only be sparsely activated on an explainable damage response template, and a part which cannot be explained by the dictionary serves as a residual error to enter blind source separation, so that a sparse damage component and a background noise source component are decoupled from the mechanism, and pollution of rain wave impact, aerodynamic noise and the like to damage judgment is reduced; simulation template coverage based on a limit load spectrum is introduced, and a normal structure response form under a typhoon working condition is incorporated into a dictionary space; and a health baseline subspace can be learned before an event, and components highly related to the health subspace in a current signal are inhibited in advance, so that subsequent sparse activation more intensively points to abnormal change, and the cross-working-condition stability is improved.

The application belongs to the technical field of building anti-collapse, and particularly relates to a method for obtaining a limit stability performance curve of a concrete structure and application thereof. The method comprises: taking limit loads of different concrete structures as training samples, training a first neural network model to obtain a limit load prediction model; determining a stable load range based on the limit load; then taking performance curves constituted by different loads and corresponding column top limit displacements of different concrete structures under different column removal conditions within the stable load range of the concrete structures as training samples, training a second neural network model to obtain a performance curve prediction model; after the limit load prediction model predicts the limit load of a to-be-predicted concrete structure, the performance curve prediction model outputs the performance curve of the to-be-predicted concrete structure according to the to-be-predicted concrete structure and the corresponding limit load. The application can efficiently and accurately obtain the limit stability performance curve of the concrete structure.

The embodiment of the invention provides an offshore fixed foundation pile-soil interface bearing characteristic analysis method, system and equipment. The method comprises the following steps: establishing a finite element model of an offshore fixed foundation; wherein the finite element model comprises a pile foundation geometric model, a soil constitutive model and a pile-soil interface cyclic load simplified constitutive model; obtaining load characteristic parameters; and the load characteristic parameters are input into the finite element model, and the limit load and the cyclic load of the offshore fixed foundation are obtained. According to the embodiment of the invention, the pile-soil interface cyclic load simplified constitutive model considering cyclic weakening is established by analyzing the mechanical properties of the pile-soil interface under the static / cyclic load, and is applied to the finite element model, so that the load characteristic analysis of the pile-soil interface of the offshore fixed foundation is carried out, and the pile-soil interface load characteristic analysis accuracy is improved. The pile-soil interface bearing capacity weakening phenomenon is well simulated, and guidance is provided for research and design of an offshore fixed foundation.