56 results about "Engineering stress" patented technology

The invention discloses a multi-scale porous structure light weight modeling method oriented to 3D printing, and belongs to the field of computer aided design and industrial design manufacture. Undera condition that characteristic constraints and a stress condition are given, through a compact support radial basis function interpolation, a smooth multi-scale porous model is constructed; the multi-scale porous model is applied to light weight modeling, and a feasible solving solution is given; through the 3D printing, an entity experiment model is obtained and is subjected to engineering stress verification; according to engineering verification result analysis, a parameter is corrected to enable the hole change of an optimization model to more approach to practical stress requirements; and through the above loop iteration process, a light weight model which meets stress requirements is obtained. By use of the method, a light weight purpose of the entity model can be truly realized, sothat the light weight design optimization period of the model is greatly shortened, the porous structure obtained by design has the advantages of smoothness, full connectivity, controllability and quasi-self-supporting, and the effectiveness and the manufacturability of light weight can be accurately guaranteed.

This disclosure describes a method for fracturing a well to improve productivity, by simulating zipper fracturing in such a way as to generate stress cages, thus minimizing anisotropy in a zone where fracture complexity is desired.

The invention discloses a residual intensity and residual life computing method for pipe gallery pipelines. The residual intensity and residual life computing method comprises the following steps: collecting the data information of defects of the pipe gallery pipelines; judging the defects are plane type defects or volume type defects; for the plane type defects, obtaining the engineering stress-strain curve of a defect pipeline material from the data information of the defects of the pipe gallery pipelines, determining a failure assessment diagram, and then computing assessment points to obtain the residual intensity of the pipe gallery pipelines; for the volume type defects, obtaining the design factors, the weld joint factors and the minimum measurement wall thickness from the data information of the defects of the pipe gallery pipelines, and obtaining the residual intensity of the pipe gallery pipelines through computing; computing basic numerical values according to the data information of the defects of the pipe gallery pipelines, and computing the residual lives of the pipe gallery pipelines according to a maximum value distribution probability density function, a reliability function, maximum corrosion depth point estimation and maximum likelihood estimation. Therefore, the residual intensity and residual lives of the pipelines in a pipe gallery area are effectively and accurately computed and predicted.

The invention discloses a data processing system based on a separated Hopkinson bar dynamical mechanical property test device. The data processing system is characterized in that voltage-time data points obtained by testing the separated Hopkinson bar dynamical mechanical property are first read, then the voltage-time data points are drawn into a voltage-time curve, the tested voltage-time curve is transformed to a needed engineering stress-strain curve and a real stress-strain curve through the human-computer interaction according to a given test parameter or by automatically inputting the parameter and a calculation formula, and the data can be examined, smoothened, modified, intercepted and outputted at any time. By adopting the data processing system, the dynamically compressed test data, the cutting data and the tensile mechanical property test data can be respectively processed; based on the humanized interface of the windows operating system, the intelligentization of the separated Hopkinson bar dynamical mechanical property data processing can be realized, the data is more flexible to process, the operation rate and convenience in operation can be improved, and the practicability is strong.

A method for engineering stress in the channels of MOS transistors of different conductivity using highly stressed nitride films in combination with selective semiconductor-on-insulator (SOI) device architecture is described. A method of using compressive and tensile nitride films in the shallow trench isolation (STI) process is described. High values of stress are achieved when the method is applied to a selective SOI architecture.

The invention provides a method for rapidly determining the buckling strain capability of a steel tube, belonging to the production control technical field of the high-deformability steel tube for a petroleum and gas pipeline. The method comprises the following steps: taking a longitudinal test piece from the tube, and then obtaining an engineering stress-engineering strain curve by a test; and calculating the critical buckling strain of the steel tube in a bending deformation mode according to a formula: epsiloncrit=15.963*Rt2.0/Rt1.0-15.139, wherein, the critical buckling strain is average strain that a compression side of the test piece stretches towards two sides over a distance which is twice as long as the external diameter length of the steel tube with a buckled position as a center. The method can help rapidly determine the critical buckling strain of the steel tube in the bending deformation mode by controlling the tensile property of the pipeline steel tube, and can carry out performance control by a conventional production control test according to the stress ratio of the critical buckling strain level so as to produce the steel tube which can meet the requirement for the critical buckling strain level.

The invention discloses a large-deformation shock compression experimental method for materials. The large-deformation shock compression experimental method is characterized in that the right end surface of a transmission bar is fixedly connected with a support block, and a piece to be tested is fixed on the left end surface of the transmission bar, and is in tight contact with the left end surface of the transmission bar; two strain gauges which are symmetrical along an axial center surface are fixed to the outer surface, close to the left end, of the transmission bar, an impact bar of which the material, the length and the diameter are all the same as those of the transmission bar is selected, and regulation is performed, so that the impact bar, the piece to be tested, and the transmission bar are coaxial; and then, the impact bar is emitted, the two strain gauges fixed to the transmission bar are used for testing strain signals of the transmission bar, the tested strain signals of the transmission bar are substituted to a relational expression, and treatment is performed, so that a time interval curve about the axial engineering stress, engineering strain and engineering strain rates, of the tested piece during an experiment is obtained. The large-deformation shock compression experimental method has the advantages that a continuous stable experiment strain rate is realized, and under the condition of the biggest strain same as a conventional Hopkinson pressure bar experiment, the strain rate can achieve the 10 S<-1> order.

The invention discloses a geosynthetics anisotropism drawing test system and method. The system comprises a test bed, a lower test box, an upper test box, a drawing loading device, a guide rail, a dial, a vertical loading device, a displacement sensor, a signal collection control device, and a jig for clamping a geosynthetics sample, wherein the circular dial, the guide rail and the lower test box are arranged on the upper surface of the test bed, the drawing loading device is arranged on the guide rail and slides freely on the guide rail; the displacement sensor for measuring the displacement of the jib is arranged on the drawing loading device; the vertical loading device, the upper test box, the geosynthetics sample and the lower test box are arranged on the test bed from up to bottom in sequence; the signal collection control device is connected with the drawing loading device, the displacement sensor and the vertical loading device. The test system and method have the advantages that the occurrence that the tested value of a geosynthetics anisotropism drawing test is seriously inconsistent with the actual engineering stress characteristic is avoided and the test process is accurate and controllable.

The invention belongs to a composite material technology, and relates to a method for processing the material performance of a composite material at a wet fitting joint in a mechanical connecting wet assembly process for a composite material structure. The influence of adhesive layer hardness and tightening torque in the mechanical connecting wet assembly process for the composite material structure is analyzed, a material laminate model, an adhesive layer model and a bolt model are analyzed respectively, toroidal and radial stress curves of a hole edge of a composite material laminate are drawn, and a method for analyzing the stress of the composite material hole edge and an engineering stress treatment method are provided, so that the problem of deficiency of analysis means for the influence of the adhesive layer hardness and the tightening torque on the stress concentration of the composite material hole edge in the wet assembly process is solved; and a composite material hole edge stress extraction and treatment method is provided, is helpful for the direct judgment of engineering technical personnel in the stress concentration of the hole edge, and has high engineering application value.

The invention discloses a method for predicting fatigue strength of a metal material by hardening strength and tensile strength, and belongs to the technical field of material science and engineeringapplication. Firstly, a true stress-strain curve is calculated according to an engineering stress-strain curve, work hardening ability parameter, namely the hardening strength can be obtained, and thehardening strength and the tensile strength are combined and fitted by two-parameter least square method to establish the relationship between the fatigue strength and the hardening strength and thetensile strength. The method effectively reduces the experimental amount required for fatigue strength prediction, greatly saves time, money and labor costs, has high accuracy, and can be widely applied to various metal materials with strong work hardening ability.

The invention relates to a direct-shear measuring method of drilling rock mass specimen preparation, which can solve the problems of high test expenses, long test period and low efficiency effectively and particularly can overcome the defect that specimen preparation is dependent on stonecutters. The method comprises the following steps of: excavating a test adit in a mountain by adopting a bursting method first, and drilling two holes upwards on a test adit bottom board by using a drilling machine, wherein one hole is a shear hole, the other hole is a specimen hole, the centers of the two holes are in the same straight line, the direction of the straight line is consistent with that of engineering stress, and the specimen hole is a test sample drill hole; reserving a rock core in the holes, taking the rock core from the shear hole for arranging a shearing test equipment, and cutting the rock mass on the middle part of the two holes for communicating; determining the drilling depth according to the position of a shear surface, and after completing a drilling workpiece, arranging a steel protective sleeve on a specimen; and arranging normal and shearing loading equipment respectively after the work is finished. The direct-shear measuring method has the advantages of simplicity, convenient operation, low cost, labor and time saving and high efficiency, and is the innovation of the direct-shear test of the site rock mass strength.

The invention belongs to the technical field of alloys and discloses a magnesium-based high-entropy alloy with high toughness and high hardness and a preparation method. By taking Mg as a base, and selecting main elements Al, Gd, Y and Zn beneficial to reinforcement and hardness improvement of a magnesium alloy, the magnesium-based high-entropy alloy with high toughness and high hardness and the preparation method are developed. The magnesium-based high-entropy alloy has an engineering stress-strain curve with a remarkable processing hardening characteristic, has microhardness of HV103.3-123.7, room-temperature tension strength of 458.01-496.65MP, and a compression ratio after breakage of 14.83-17.28%, and in addition, the magnesium-based high-entropy alloy disclosed by the invention is simple in preparation method and easy in condition control.

The invention discloses a method for determining uniform ductility of a hi-grade steel pipeline steel pipe, and relates to the technology of pipeline steel materials. The method comprises the following steps of: picking a tensile sample on a pipe body of a hi-grade pipeline, and obtaining an engineering stress-engineering stress curve through a tensile test; taking two percent points toward the stress positive and negative directions near points corresponding the biggest press on the engineering stress-engineering stress curve to fit a data range; and fitting the engineering stress-engineering stress curve in the data range, and obtaining the uniform ductility. The invention also discloses a device for determining the uniform ductility of the hi-grade steel pipeline steel pipe. The method for determining the uniform ductility of the hi-grade steel pipeline steel pipe has the advantages that the engineering stress-engineering stress curve of the tensile test is fitted, the mathematical expression of the curve is obtained, the real uniformity ductility numerical value of the material is determined on the foundation, the deformation performance of the steel pipe is objectively judged, and an erroneous judgment is avoided.

The invention discloses a method for obtaining high-precision hardening model parameters of a material in a complex stress state. The method comprises the following steps: S1, obtaining a force-displacement curve of the material in a uniaxial tensile stress state; S2, calculating an engineering stress-engineering strain curve; S3, calculating a true stress and true strain curve; S4, calculating an effective stress-strain curve; S5, performing fitting epitaxy on the effective stress-strain curve to obtain an epitaxial stress-strain curve; S6, adjusting the line shape of the fitting curve; S7, establishing numerical models for the material samples in different stress states, and comparing force-displacement curves in test and simulation results; and S8, returning to the step S6, and optimizing the weighting coefficient until the benchmarking result in the step S7 meets the requirement. According to the method, material samples in different stress states are subjected to simultaneous benchmarking and optimization iteration to obtain high-precision hardening model parameters, the problem that material performance characterization in different stress states cannot be considered at the same time in the existing hardening model parameter establishing process is solved, and the defects existing in an existing method are overcome.

The invention relates to a variable-rate tensile curve evaluation method, which combines a metal dynamic deformation theory with a rheological law, correlates strain rates with yield strength and tensile strength of a material, and evaluates a variable-rate engineering stress-strain curve by actually measuring the yield strength and the tensile strength of each sample at each strain rate by taking0.2%-1% as a standard. Compared with the prior art, the variable-rate tensile curve evaluation method has the beneficial effects that the variable-rate tensile curve evaluation method overcomes the defects that an existing method is large in random error and the like, a reasonable variable-rate engineering stress-strain curve range can be accurately evaluated, processed effective stress-strain curves are not overlapped, and the CAE collision simulation requirement is met.

The invention discloses an anchor rod engineering stress simulation experimental device. The anchor rod engineering stress simulation experimental device comprises a U-shaped groove, a triangular prism cushion block, a loading cushion block, side baffles, an approximately trapezoidal test piece and anchor rod test pieces. The anchor rod engineering stress simulation experimental device can be used for simulating the stress state of an anchor rod in an engineering field, and truly reflecting the interaction process between a surrounding rock and the anchor rod in tunnel engineering to obtain a true stress distribution curve of the anchor rod, so that the anchor rod engineering stress simulation experimental device has great significance on the research on the properties of stress, deformation, damage and the like of a deep high stress anchored rock mass. According to the anchor rod engineering stress simulation experimental device, part of a deeply buried circular tunnel surrounding rock is subjected to analysis, so that compared with an existing whole sectional model test device, large-scale model tests can be carried out, and the test results are closer to those of the anchor rod in the practical application.

The invention provides a vertical soil engineering grid, comprising rib belts which are arranged vertically and in a 45-degree cross grain, the space between the rib belts form a rhombus grid cavity, an injection molding node is arranged at the connection position of the two rib belts, the injection molding node is formed by integrated injection molding a middle cylindrical pin and a fixed piece on the periphery, the two connected rib belts are arranged in parallel, a plurality of sets of upper and lower cracks are arranged evenly at corresponding positions, strip rib blocks are formed between each set of upper and lower cracks, and the cylindrical pin is passed through the spaces formed by a plurality of strip rib blocks and rib belts. After the vertical soil engineering grid is paved in a foundation, the stretching resistance, the yield strength, the shearing force, the lock force and the frictional resistance are improved evidently, great intensity of pressure in the construction process can be borne, the soil body compacted density is increased, the soil fixing ability is increased greatly, the uneven sedimentation is improved evidently, the sedimentation after the construction is reduced, the vertical soil engineering grid is anti-chemical erosion, the engineering stress has time effect, the safety is good and the intensity is high.

The invention discloses a method for testing large deformation impact tension of a material. The method is characterized in that a supporting block is arranged at the upper end of a bracket; a tubulartransmission bar is vertically arranged, and the upper end of the transmission bar is fixedly connected to the supporting block; tubular incident bar which is the same as the transmission bar in theaspects of material, length and diameter is selected and vertically coaxially arranged below the transmission bar; a boss is integrally arranged at the lower end of the incident bar; a tested part isfixed between the lower end of the transmission bar and the upper end of the incident bar; an impact rod is launched to impact the boss which is fixed at the lower end of the incident bar, thus a strain signal can be tested; and the tested signal is substituted into a relation to obtain an axial engineering stress, engineering strain and engineering strain rate time history curve of the tested part in the test. The method has the advantage that the continuous stable test strain rate is achieved; and in addition, the strain rate is up to 10S<-1> order under the maximum stress the same as that of a traditional Hopkinson bar test.

The invention belongs to the technical field of engineering stress calculation, and provides a mechanical model of a scaffold based on a pulling and lifting unloading method and a solving method of the mechanical model. The model mainly comprises a single vertical rod model formed on the basis of an inner vertical rod or an outer vertical rod of the scaffold, wherein the single vertical rod model comprises k1, G1, k2, G2, k3, G3... kn, Gn and kn + 1 which are linearly and sequentially arranged, in which ks1, ks2... ksn are correspondingly connected between k1 and G1... kn and Gn; herein, the k1 is the vertical rigidity of the scaffold at the foundation section; the ks1... ksn is the vertical rigidity of the unloading steel wire rope at the corresponding section of the corresponding scaffold; the G1... Gn are equivalent concentrated vertical loads at the first section... the nth section of the vertical rod respectively; the k1,... kn + 1 are equivalent springs at the first section to the nth section of the vertical rod respectively. According to the method, the stress calculation accuracy and the calculation convenience of the scaffold under the pulling and lifting unloading method can be effectively improved.