153 results about "Damage factor" patented technology

A system to predict a fatigue life of an aluminum alloy is disclosed herein. The system comprises a computer-readable medium cooperative with micromechanics-based fatigue life models for cyclic multiaxial loading. The fatigue life models predict the fatigue life by processing information received by the system relating to the aluminum alloy and the stress state present in the aluminum alloy. The received information comprises at least one of: a critical shear plane, a damage factor, a hardening factor defined by at least one of a plurality of uniaxial cyclic hardening factor parameters related to probabilistics of defects and microstructure characteristics in the aluminum alloy, an additional hardening factor related to non-proportionality, and thermophysical and mechanical properties of the aluminum alloy. The defects and microstructure characteristics can be calculated using mathematical modeling of casting, solidification and heat treatment processes or by an extreme value statistics based on metallography measurements.

The invention discloses a construction method for a rock freeze-thaw damage constitutive model under the action of constant confining pressure. Based on a popularized strain equivalence principle, taking the joint action of two damage factors (freeze-thaw cycle and load) into consideration, the invention proposes an expression of a total damage variable. If the strength of a rock element body is subject to Weibull distribution, on the basis of a D-P failure criterion and geometrical conditions at peak points of a rock stress-strain curve, an expression of a random distribution variable F, a distribution parameter m and F0 is obtained, and a rock freeze-thaw damage constitutive model under the action of constant confining pressure is created. A triaxial compression experiment is carried out on a rock under the action of freeze-thaw cycle, and the experiment verifies the rationality of the model. The method disclosed by the invention is a method combined with theoretical derivation and experimental verification. The theoretical curve of the rock damage constitutive model created by the method is identical with the experimental curve, the mechanical behaviors of a rock under various confining pressures and freeze-thaw cycle numbers can be perfectly reflected, and a theoretical guidance is provided for designs and construction of cold-region projects.

The invention discloses a bridge structure damage diagnosis method based on an accumulated damage factor sequence under a complex environment, belonging to the field of bridge structure damage diagnosis in practical operation. The invention solves the problem of low accuracy of a bridge structure damage diagnosis method based on massive monitoring data under a complex environment. The bridge structure damage diagnosis method based on an accumulated damage factor sequence under a complex environment, disclosed by the invention, comprises the following steps: constructing a damage diagnosis threshold by adopting bridge structure monitoring data under a healthy state, and comparing an accumulated damage discrimination factor with a damage diagnosis threshold under states to be diagnosed at different moments so as to discriminate that whether a bridge structure is damaged or not. Meanwhile, by adopting a dependence scrambling strategy, the method disclosed by the invention is capable of eliminating influences of various environment factors to bridge structure monitoring data. The bridge structure damage diagnosis method is capable of improving the accuracy of bridge structure damage diagnosis under a complex environment condition, and is suitable for solving the problem of bridge structure damage diagnosis of the practical operation.

The invention discloses a bridge moving load and damage synergetic recognition method based on L1/2 regularization. The method includes the steps that a plurality of structural response measurement sensors such as an acceleration sensor, a displacement sensor and a strain sensor are arranged on a bridge according to the aim and accuracy requirement of bridge structure health monitoring; a finite element model of the bridge is established through beam elements; moving loads are equivalent to a linear combination of rectangular loads, and bridge damage is equivalent to element stiffness reduction; the moving loads are recognized through a Tikhonov regularization method under the condition that an element damage factor is given, a reconstructed response is calculated with the moving loads, the range of the residual L2 norm of a measured response and the reconstructed response is obtained through comparison, and an L1/2 penalty term is introduced to establish an objective function with the element damage factor as an optimized parameter; a constraint optimization problem is solved with a Matlab optimization toolbox, the corresponding damage factor is the structural damage recognition result when the objective function is the minimum, and correspondingly the moving loads worked out through Tikhonov regularization solving are the moving load recognition result.

The invention relates to a semi-opening greenhouse cultivation technology for a peach tree in a low-latitude plateau area. The technology is characterized in that a greenhouse frame is arranged on one surface of a greenhouse; a layer of inspect proof nets and a layer of heat preserving quilts sequentially cover the frame; the heat preserving quilts are controlled by a contracting and stretching bracket to the contracted and stretched, and therefore, the temperature in the greenhouse of the peach tree can be controlled in different growth periods and under the changeful air temperature condition at the low-latitude plateau area; meanwhile, the technologies like the water and fertilizer control technology and the special fruit bag utilizing technology are adopted, thus the damage factor under the natural condition is removed, and the natural growth state of the peach tree is remained to the maximum; the applied pesticide is about 20% that under the common planting condition, the applied chemical fertilizer is about 30% that under the common planting method, the water irrigated is about 40% that under the common planting condition, and the output is more than 150% that under the common planting condition; in addition, the peach quality is far more than that of common peach; the market price is the peach is more than 5 time that of the common peach.

The invention belongs to the field of damage evaluation, and relates to a representation method of drilling damage to a carbon fiber composite, in particular to a comprehensive representation method of drilling damage to a carbon fiber composite. According to the representation method, delamination damage, burr damage and tear damage generated in the actual machining process of the composite are considered, a damage representation factor formula is derived through weight coefficients of influences of the three kinds of damage on workpiece performance, and after the weight coefficients of the three kinds of damage are determined, a comprehensive representation factor of the machining damage is obtained by establishing a regression model between the three damage factors of delamination, burrs and tear and workpiece mechanical performance parameters. Calculation is simple, results are accurate, the comprehensive damage evaluation factor obtained through calculation is more convincing, and therefore the method has good engineering application prospects.

The invention discloses a method for testing concrete uniaxial tensile stress strain relationship through sound emission. The method comprises the following steps: performing three-point bending fracture test on a concrete beam, and monitoring material damage and strain development in the crack development and evolution process in a fracture process area by using a sound emission tester and a strain tester respectively; according to the initial gap length, the critical fracture process area length, the loading total time and the fracture initiation time, determining the time t required by thewhole destruction process of the first critical fracture process area; according to the sound emission characteristic of material damage and evolution within the time t, fitting a relation expressionbetween a material damage factor and fracture process area strain development within the time t and establishing a damage factor expression taking strain as internal variable so as to obtain a concrete uniaxial tensile stress strain relationship model. The method provided by the invention has important application value in developing concrete constitutive theory and test research thereof.

The invention discloses a method for evaluating the dynamic damage of a material under repeated impacts, which comprises the following steps of: 1. measuring and calculating the original average wave speed v0 of a test specimen prior to an impact test by using the ultrasonic method; 2. carrying out a repeated impact test on the test specimen; 3. Measuring by adopting an ultrasonic wave method and calculating the average wave speed vn of the test specimen after the nth impact; 4. calculating the damage factor of the test specimen after the nth impact: Dn=1-vn2/v02; and 5. calculating the arithmetic average of the damage factors of at least three test specimens made of the same material after the nth impact, and evaluating the dynamic damage degree of the material with factors under different impact times. The invention has simple measuring method, is suitable for measuring various materials of different characters, can be used for quantitative evaluation on the damage degree of materials and structures under dynamic load effects such as explosion, impact, penetration and the like, improves the accuracy and the reliability of the evaluation method, and can carry out quantitative comparison and evaluation on the repeated impact resistance of different materials.

The invention discloses a metal structure fatigue life calculation method based on a material corrosion damage factor and a weld crack damage factor.Damage factors of two factors of corrosion and weldjoint of the steel structure to the yield strength of the steel structure are obtained; finally, the yield limit of the material after aging along with time is solved; a model of the steel structureyield characteristics changing along with time is established by utilizing the factors, so that the reliable yield strength limit of the steel structure is obtained, an intersection point exists at acertain position by utilizing a steel structure S-N curve considering damage factors and a stress cycle, and the intersection point is a residual service life value needing to be predicted by people.According to the method, the influence of corrosion and weld crack damage on the metal structure of the hoisting machine in actual use is fully considered, and a material corrosion factor and a weld crack damage factor are introduced, so that a calculation result is more practical and accurate, and the method is suitable for application of metal structure safety assessment.

The invention discloses an intelligent identification method and system for damage of an oil-gas bed based on factor expression. The method comprises the following steps that (a) damage factors of different reservoir types, conditions and reservoir characteristics are represented qualitatively and quantitatively in a unified manner by using a factor expression method; (b) a prerequisite classification tree of oil-gas bed damage identification is established by combining oil-gas bed damage factors with semantic transformation; (c) the prerequisite classification tree is used to establish a damage identification database with an intermediate conclusion node; and (d) different sensitive data via factor expression is used to calculate proportion of a condition component, accuracy and a threshold in the damage identification database, the intermediate conclusion node is analyzed and determined, and a two-layer knowledge tree is used to obtain data of different damage types and degrees of the oil-gas bed. The method and system have the advantages that data expression is unified, the inference complexity is low, the inference efficiency is high and the conclusion accuracy is high.

The invention discloses a reasonable width determination method for a gob-side entrydriving narrow coal pillar based on fracture evolution. The method comprises the following five steps: observing roadway deformation and coal pillar fracture distribution characteristics on site; establishing a UDEC-Trigon numerical model to match with on-site condition to determine model parameters; reversing an evolution rule of fractures in different coal pillar widths; determining the reasonable coal pillar width fracture evolution penetration; and finally providing a high pre-stressed anchor and anchor cable technology to control stability of the coal pillar. By adopting a damage factor for quantifying assessment of fracture evolution penetration to finally determine the optimum reasonable width of thegob-side entrydriving narrow coal pillar, inner fractures of the coal pillar in a service period are not penetrated, and gas in a goaf can be isolated effectively while the coal pillar is carried stably.

A method for predicting fretting fatigue life of a nickel-base single crystal alloy turbine blade tenon includes establishing a fretting fatigue contact analysis model of that nickel-base single crystal alloy turbine blade tenon; calculating the model under the given working condition and obtain the analysis parameters, which include shear stress, tangential stress and relative slip distance at different positions of the contact surface; determining the shear stress damage factor at different positions of the contact surface of the model under a given working condition; the cumulative dissipative energy damage factors at different positions of the contact surface of the model are determined according to the given operating conditions and analysis parameters. According to the shear stress damage factor and cumulative energy dissipation damage factor, the fretting fatigue comprehensive damage factor is determined, and the fretting fatigue life of nickel-based single crystal alloy turbineblade tenon is obtained. The fretting fatigue life prediction method of the nickel-based single crystal alloy turbine blade tenon can accurately predict the fretting fatigue life of the nickel-basedsingle crystal alloy turbine blade tenon.

A method for detecting damage in a bearing of a wind turbine includes collecting vibration data relating to the bearing. Another step includes storing the vibration data in a memory device. The method also includes identifying a plurality of harmonics in the vibration data that are indicative of bearing damage. Further, the method includes eliminating harmonics within a specified frequency proximity to areas of high energy content representative of normal gearbox operation. Moreover, the method includes determining at least one of increases in energy or a variance of the energy within each of the remaining harmonics and calculating a damage factor of the bearing as a function of a least one of the increases in energy or the variance of the energy within each of the remaining harmonics. Accordingly, the method includes comparing the damage factor to a predetermined damage threshold, wherein a damage factor exceeding the predetermined damage threshold may be indicative of a damaged bearing.

The invention relates to a steel frame greenhouse technology for peach tree in low-latitude plateau area. The technology is characterized in that steel pipes are welded to form a semicircular steel frame greenhouse to be fixed to the peach tree farmland; a plastic greenhouse film and an inspect proof nets cover the frame; a nonwoven fabric covering surface is hung in the greenhouse; the plastic greenhouse film and the nonwoven fabric are contracted and stretched to realize the control to the temperature in the greenhouse of the peach tree at different growth periods and under the changeful air temperature condition at the low-latitude plateau area; meanwhile, an underground irrigating device, a novel double-layer ground film and a special fruit bag and other technologies are adopted, thus the damage factor under the natural condition is removed, the natural growth state of the peach tree is remained to the maximum, and the quantity of applied pesticides and chemical fertilizers is greatly decreased; the water for irrigating is about 40% that under the common planting condition, and the output is more than 150% that under the common planting condition; in addition, the peach quality is far more than that of the common peach, and the market price is 5 times that of the common peach.

The invention relates to a viscoelastic composite damping vibration attenuation rubber plate of a ship deck. The vibration attenuation rubber plate is characterized by being composed of four layers of an aluminum foil restraint layer, a viscoelastic damping layer, a micropore foaming damping layer and a viscoelastic and self-bonded damping layer which are arrayed from outside to inside sequentially. Because the vibration attenuation plate is composed of four layers of the aluminum foil restraint layer, the viscoelastic damping layer, the micropore foaming damping layer and the viscoelastic and self-bonded damping layer which are arrayed from outside to inside sequentially, not only can the damping effect be improved, but also the construction is convenient, especially for the operation of the vertical surface and the top surface, therefore the vibration attenuation plate can be conveniently bonded and fixed on the inner layer of the ship deck through the viscoelastic and self-bonded damping layer, is not required to be fixed through heating, and is convenient to use; the structural damage factor is not less than 0.1 within a temperature range from minus 20 DEG C to 60 DEG C, and the vibration attenuation effect reaches more than 3db; compared with the existing single-layer butyl rubber, the vibration attenuation rubber plate has the advantages that the damping vibration attenuation performance is more superior, and the use temperature range is wider.

The invention relates to a carbon fiber composite material fatigue damage probability imaging method based on a ToF damage factor, and belongs to the technical field of engineering structure health monitoring. The method comprises the steps of firstly, uniformly dividing a monitored area in a piezoelectric sensor network into N small grids, and taking each small grid as a pixel point; then calculating a ToF damage factor of each excitation-sensing channel; secondly, calculating the damage existence probability of each pixel point in each excitation-sensing channel according to the ToF damage factor; and finally, superposing the damage probability of each pixel point in each excitation-sensing channel, mapping the damage existence probability of each pixel point into a pixel value and imaging, and taking the position with high damage probability in an imaging image as the possible damage existence position. Compared with a traditional damage probability imaging method, damage can be accurately recognized and positioned, the visualization effect of damage imaging can be effectively improved, and the approximate shape and size of the damage can be obtained.

The invention discloses a damage mechanics-based high-strength metal material amplitude variation ultra-high cycle fatigue life predication method. The method is based on an ultra-high cycle fatigue test result and a damage mechanics model, and the high-strength metal material amplitude variation ultra-high cycle fatigue life predication method is provided. The ultrasonic fatigue test is used to rapidly acquire the ultra-high cycle fatigue performance of a high-strength metal material, the test frequency is 20 kHz, only 13.9 hours are needed to finish 109 cycles; based on the nonlinear damagemechanics theory, a damage factor of the amplitude variation stress level is introduced, a material amplitude variation ultra-high cycle fatigue life predication model is established, and the ultra-high cycle fatigue life is quantitatively predicated on amplitude varied load. The thought of the assessment model is clear, and the computation is simple and fast.

The embodiment of the invention provides a gear damage factor detecting method and device and a wind turbine generator system. The method comprises the steps that a collected gear signal is subjectedto designated axis time domain synchronous average TSA treatment, and a TSA waveform signal is obtained; an envelope line corresponding to the TSA waveform signal is obtained according to the TSA waveform signal; the envelope line is converted into a corresponding an order spectrum according to the set conversion rule; and a gear damage factor is detected according to the order spectrum. Accordingto the technical scheme of the embodiment, the gear damage factor can be determined according to a gear signal and designated axis information, the error of the obtained gear damage factor is decreased, and the accuracy of gear damage evaluation is improved.

The invention provides a pipe hinge space deployable structure optimization design method considering composite material damage. The method comprises the following steps: establishing a finite elementmodel of a pipe hinge space deployable structure; obtaining equivalent material performance and failure parameters by utilizing material homogenization; performing simulation analysis on folding of the pipe hinge to obtain a ppipe hinge bending moment-turn angle curve and a damage factor; establishing a parameter optimization model which takes strain energy as a target, takes the thickness, the groove length and the groove width of the pipe hinge as design variables and takes a material damage factor as a constraint; constructing an objective function and a response surface of the constraintfunction based on a response surface method, and realizing explicit representation of the constraint and the objective function; solving results by using genetic algorithms. The problem that the composite material pipe hinge loses efficacy in the folding process is considered, the design period of the space deployable structure of the pipe hinge is shortened in an optimized mode, the working efficiency is improved, and the design cost is saved.

The invention discloses a BIM-based building facility maintenance supervision system. The system comprises an acquisition module, an analysis module, a monitoring module, a processor, an alarm, a database, a timing unit and intelligent equipment. The acquisition module is used for acquiring facility work information, wherein the facility work information comprises work duration data, fault frequency data, temperature data and startup and shutdown frequency data. The data is transmitted to the analysis module through the processor. The analysis module receives the facility work duration data, the facility fault frequency data, the facility temperature data and the facility startup and shutdown frequency data. According to the invention, the acquisition module and the analysis module are arranged, the damage factors of the facility is analyzed, the damage degree, the average damage coefficient and the dispersion degree of the damage coefficient of the facility are calculated, and the fault judgment module is used for judging the use of the facility according to the analysis result of the analysis module to increase the safety analysis of the facility, so that the safety of the facility is better maintained, and the working efficiency is improved.

The present invention relates to an online monitoring technology of power supply rectifying equipment, in particular to an intelligence expert analysis method for the electric security of electrolytic aluminum. The intelligence expert analysis method for the electric security of the electrolytic aluminum comprises a data acquisition layer, a data storage layer, and a data application and analysis layer. The analysis method comprises the steps of a data acquisition step, a data storage step, and a data application and analysis step. The present invention has the advantages that the method is a total solution which integrates the comprehensive analysis results of oil chromatogram analysis data, load sharing analysis data, partial discharge analysis data, and oil temperature analysis data and display together. The present invention realizes the detection to the running state of the key link of a power supply system, provides an analysis report on the running state of a power supply system, promptly discovers the hidden danger of the equipment, reduces the damage factor of the power equipment, and avoids the great direct economic loss caused by accidents. The intelligence expert analysis method for the electric security of the electrolytic aluminum is suitable for the automated control system of the power supply system.

The invention discloses a composite material plate structure damage monitoring method, and belongs to the technical field of composite material plate structure damage monitoring. The method is designed for solving the problems of low efficiency, low precision, and no simultaneous identification of many damages of present methods. The composite material plate structure damage monitoring method is a damage monitoring method based on a piezoelectric element and a Lamb wave. The method comprises the following steps: predetermining the damage position of a composite material plate structure to be monitored by using a damage factor technology, and imaging the area which is predetermined to be damaged in order to determine the accurate position of the damage. The composite material plate structure damage monitoring method can save a lot of monitoring time, improves the monitoring efficiency, can realize multi-damage positioning, and enhances the determination accuracy of the number and the position of the damages.

The invention relates to a self-repairing concrete structure. The self-repairing concrete structure comprises a concrete member. A plurality of glass tubes are embedded inside a tension area of the concrete member, wherein openings of the glass tubes are sealed, and the glass tubes contain chloroprene rubber adhesives. The axial direction of the glass tubes is parallel to the tension direction of the tension area of the concrete member. The invention further provides a manufacturing method of the self-repairing concrete structure. According to the self-repairing concrete structure, the safety and long-term durability of great civil infrastructures such as high-rise buildings, bridges and nuclear power stations can be ensured, damage caused by a plurality of damage factors such as typhoon and earthquake shock is reduced, the repaired bearing capacity can be recovered to be 99%, and the service life of the concrete member is prolonged.