406 results about "Cyclic loading" patented technology

A system and method for joint restoration by extracapsular means includes an actuator operable to apply a force to a portion of a bone to effect a change in the joint space geometry. One embodiment of the system includes an actuator operable to apply a cyclic loading to subchondral bone of a femur, wherein loads of a predetermined magnitude are alternately applied and released. Between periods of cyclic loading, rest periods are provided where no load is applied. Over time, the femoral joint surface is remodeled in accordance with the location, direction, magnitude, and frequency of the loading.

The invention relates to an evaluation method of earthquake resistant performance of a steel tube concrete building. A building support component is formed by steel tube concrete. The evaluation method comprises the following steps of establishing a space fiber beam finite element model of the steel tube concrete building, developing an analysis method suitable for a fiber beam, considering that the confinement effect and the material characteristic of the elasto-plasticity under earthquake cyclic loading damage a constitutive model and a corresponding subprogram, calculating the finite element model by adopting a software and combining with the material subprogram, evaluating the earthquake resistant performance, and designing the earthquake resistant measure of the building. In the provided evaluation method of the earthquake resistant performance of the steel tube concrete building, the earthquake resistant performance of the building is evaluated on the basis of the maximum inter-story displacement angle limit value required by a steel tube concrete structure by establishing the space fiber beam finite element model of the steel tube concrete building, developing the analysis method suitable for the fiber beam, considering that the confinement effect and the material characteristic of the elasto-plasticity under earthquake cyclic loading damage the constitutive model, calculating the finite element model by adopting the software and obtaining the maximum inter-story displacement angle of the building, and building earthquake resistant measures are planed according to the evaluation result of the earthquake resistant performance of the building.

A method and system for determining damage prediction of a component. The component may be critical component used in an aircraft or other vehicle experiencing cyclic loading. The method and system determines the ΔK, Kmax and Kinternal values for the component and utilizes these values in order to predict damage and / or failure of the component.

A novel prefabricated shearwall is disclosed with improved structural characteristics in terms of its ability to 1) transfer lateral loads to the foundation, 2) resist bending moments normally arising in conventional shearwalls between hold-down hardware and end posts or vertical framing members, 3) effectively diffuse stresses known to result in nail fatigue, and 4) reduce slippage between the bottom of the end posts and base in response to cyclic loadings. These superior properties result partly from its geometry in lower, or shear force transfer region, accompanied by thrust block / anchor rod assemblies to provide stiffness and strength over the lower portion of the end posts. Furthermore, specialized wrap-around connector plates that cover a portion of the bottom surface of these end posts also contribute to the enhanced prefabricated shearwall design.

The invention discloses a method for constructing a turbine disc structure probability design system. The method comprises the following six steps of: 1, analyzing a turbine disc structure probability design flow, analyzing a failure mode, and determining a system functional model of the probability design flow; 2, extracting characteristic parameters of a turbine disc meridian plane and a mortise respectively to finish parametric modeling; 3, storing a common material for a turbine disc in a form of spreadsheet to form a material base tool; 4, integrating a rain-flow counting program, processing a standard loading spectrum, providing primary and secondary cyclic loading parameters for low cyclic analysis, integrating an MATLAB data processing function, and expressing fatigue-creep coupling by using a double-parameter characteristic function; 5, researching the heteroscedastic characteristic of a strain life model and providing a model to realize heteroscedastic recursive processing of fatigue test data; and 6, constructing a turbine disc structure probability design system database based on the principle of using a task as a basic unit and using the turbine disc probability design flow as a core. The method has broad application prospect in the field of aerospace engines.

A system and method for joint restoration by extracapsular means includes an actuator operable to apply a force to a portion of a bone to effect a change 5 in the joint space geometry. One embodiment of the system includes an actuator operable to apply a cyclic loading to subchondral bone of a femur, wherein loads of a predetermined magnitude are alternately applied and released. Between periods of cyclic loading, rest periods are provided where no load is applied. Over time, the femoral joint surface is remodeled in accordance with the location, direction, magnitude, and frequency of the loading.

A method and apparatus are disclosed for predicting the service life of a metallic structure subjected to cyclic loading. Such structures experience fatigue, which can lead to failure after a number of loading cycles. The disclosed invention allows for an accurate prediction of the number of cycles to failure for a metallic structure by observing the slope of the rise in surface temperature of the structure after the cyclic loading has begun. The method of this invention provides early and accurate predictions of service life and does not require destructive testing. The method and apparatus of the present invention may be installed on working equipment, thus providing service life predictions for materials in real world use. The invention uses an empirically derived relationship that was confirmed using analytical relationships and material properties. The derived formula uses two constants that may be determined empirically using a disclosed process. The constants also may be estimated mathematically. The apparatus may include a wireless temperature sensor mounted on the metallic structure of interest and a data analysis unit to perform the needed calculations.

The invention discloses a cyclic shear apparatus which belongs to mechanic characteristic testing equipment and is used for observing the mechanical characteristic of the contact surface between structural member and soil. The cyclic shear apparatus consists essentially of a soil container vehicle which is arranged inside a bracket, a normal boundary control unit, a data collecting system and a hydraulic loading and control system which is fixed on the bracket; the soil container vehicle is arranged on a horizontal track on the internal bottom surface of the bracket; testing soils are fully filled in the vehicle where a structural panel is horizontally arranged; the normal boundary control unit is arranged on the upper surface of the structural panel; furthermore, the soil container vehicle is provided with an organic glass window. The cyclic shear apparatus can lead the static and dynamic mechanical characteristic of the contact surface under complicated stresses to reappear; furthermore, the cyclic shear apparatus directly exerts normal boundary conditions on the contact surface and measures the deformation of the contact surface due to bearing force, thus improving the testing and measuring precision; digital photography is used for directly recording the microscopic phenomena of the soil gains such as microscopic state arranging, sliding of the gains along the long axis direction and along the structural surface, rotating of the gain, and crushing of the gains, etc. so as to facilitate the analysis; furthermore, the cyclic shear apparatus can further determine the distribution of relative displacement of the soil and structural member along the contact surface and the thickness of the contact surface.

The invention discloses an indoor experimental device for simulating interaction of a deep water drilling underwater casing string and seabed shallow soft soil. The indoor experimental device comprises a hollow barrel-shaped object (1), a bottom clamping device (2), a variable cross-section casing string combination (3) and a data acquisition system (15), wherein the bottom of the hollow barrel-shaped object (1) is provided with the bottom clamping device (2) which is used for clamping and fixing the bottom end of the variable cross-section casing string combination (3) for an experiment; and the data acquisition system (15) is connected with a force sensor (12) of a cyclic loading device (9), an acceleration sensor (10) and a telescopic displacement sensor (11) which are arranged at the top of a casing string, a strain gauge (6) attached on the pipe wall of the variable cross-section casing string combination (3), and a soil pressure meter embedded in the periphery of the variable cross-section casing string combination (3), and is used for acquiring experimental data in real time. According to the indoor experimental device, the indoor experiment research of the interaction mechanism of the underwater casing string and the seabed shallow soft soil under the action of a transverse circulating load under different working conditions of deep water drilling can be completed, an experiment result can provide support for deep water drilling in China, and remarkable economic benefit is brought.

The invention discloses an ocean engineering pile foundation experiment simulation apparatus and method under long-term horizontal cyclic loading. The apparatus comprises: an osmotic force system which provides continuous pressurized water for a saturated sandy soil foundation so that a uniform osmotic flow field forms in the sandy soil foundation to simulate a hyper-gravity environment; a displacement control loading system and a force control loading system that apply horizontal cyclic loadings to an offshore wind turbine superstructure model; a measuring system used for measuring water pressure before the entry into the saturated sandy soil foundation, displacements of the offshore wind turbine superstructure model and a pile model, strain of the pile model, and surface displacement of sandy soil; an uninterrupted power supply system used for powering the osmotic force system, the displacement control loading system, the force control loading system and the measuring system, thereby ensuring all systems can run stably in a long time; the invention also provides an experiment method of the apparatus; the apparatus and the method are widely applicable and suitable for various ocean engineering structures such as oil platforms and offshore wind turbines.

A support structure for an offshore device and a method of assembling and installing the support structure, is provided including a vertical guide sleeve having, three elongated guide sleeves positioned around the vertical guide sleeve, and various braces connecting the elongated sleeves and the vertical guide sleeve. The support structure also includes a transition joint including a cylindrical portion for connection to an offshore device, such as a support tower of a wind turbine assembly, and a convex portion connected to the vertical guide sleeve. The transition joint may include a strengthening material in contact with an inner surface. The vertical sleeve, elongated sleeves, braces, and transition joint can be assembled onshore with lower piles installed in the elongated sleeves, this guide portion of the structure transported to the offshore location, and then piles driven to secure the structure to the floor of a body of water. The support structure minimizes the costs and time associated with material, assembly, and installation, while possessing sufficient strength, and effectively and efficiently handling and transferring loads from the wind turbine to the support surface throughout operation and while maintaining excellent fatigue resisting characteristics to withstand the extensive cyclic loading induced by the wind and waves.

A method and system for determining damage prediction of a component. The component may be critical component used in an aircraft or other vehicle experiencing cyclic loading. The method and system determines the ΔK, Kmax and Kinternal values for the component and utilizes these values in order to predict damage and / or failure of the component.

The invention provides a loading and deloading control method for a power generation system of an automobile fuel cell. The method comprises the following steps of: during loading, setting a maximum power gain sigma(x), comparing the maximum power gain sigma(x) with a difference value delta(P) between the power P(whole automobile) required by a whole automobile and the loading power P of the conventional fuel cell to determine a loading amount, and calculating the allowable power P(allowable) to be output by the power generation system of the fuel cell; adjusting corresponding parameters of the power generation system of the fuel cell according to the calculated allowable loading power P(allowable); after the adjustment is finished, returning a finish signal, repeatedly and cyclically loading until the power P(whole automobile) is equal to the power P(allowable), and cyclically loading repeatedly until the power P(allowable) is equal to the power P(whole automobile); during deloading, directly deloading; and after finishing the deloading, adjusting the parameters of the power generation system of the fuel cell. The method has the advantages that: by continuously loading according to low gain, the damage of gas insufficiency, antipole and the like to membrane electrodes, which are caused by low mass transfer because of high-speed large load loading, is reduced; and the service life of the power generation system of the fuel cell is prolonged.

The invention relates to a cyclic test device for fatigue of an aeroengine compressor blade. The cyclic test device comprises a centrifugal force loading assembly for simulating cyclic loading of centrifugal force on the aeroengine compressor blade during working; the test device also comprises a high-frequency vibration loading assembly for simulating high-frequency loads on the aeroengine compressor blade during working; the high-frequency vibration loading assembly comprises vibrating table, a support A for fixing a compressor blade test piece and a support B for fixing the centrifugal force loading assembly, wherein the vibrating table is used for applying high-frequency vibration on the compressor blade test piece. The cyclic test device for the fatigue of the aeroengine compressor blade is simple in structure and convenient to operate; the cyclic test device is capable of simulating the low cyclic loading of the centrifugal force and the high-frequency loads on the aeroengine compressor blade during working so that the test state is completely consistent with the actual working state, and therefore, the centrifugal force loading test and the high-frequency load test of the compressor blade are realized, completely trustable predetermined safe cycle life is provided and then potential safety hazards in use can be avoided.

An execution unit circuit for use in a processor core provides efficient use of area and energy by reducing the per-entry storage requirement of a load-store unit issue queue. The execution unit circuit includes a recirculation queue that stores the effective address of the load and store operations and the values to be stored by the store operations. A queue control logic controls the recirculation queue and issue queue so that that after the effective address of a load or store operation has been computed, the effective address of the load operation or the store operation is written to the recirculation queue and the operation is removed from the issue queue, so that address operands and other values that were in the issue queue entry no longer require storage. When a load or store operation is rejected by the cache unit, it is subsequently reissued from the recirculation queue.

The invention discloses a multi-carrier cyclic loading and unloading device which is characterized by comprising a machine station with a carrying table board, a plurality of object carrying units capable of performing reciprocating motion on the carrying table board of the machine station, a horizontal convey system used for realizing the reciprocating motion of the object carrying units, a lifting and conveying system used for vertically lifting and conveying workpieces on the object carrying units, and a control system used for controlling the horizontal convey system and the lifting and conveying system. The multi-carrier cyclic loading and unloading device has the benefits that 24 groups of object carrying units are arranged on the carrying table board, and when products on one group of object carrying units are lifted for processing, a photoelectric sensor can automatically tell the front and back of the product and the position. According to the invention, a continuous loading device realizes automatic continuous material conveying, the operation is convenient, the manpower investment is reduced, and the work efficiency is greatly improved.

A cyclic loading shear tester for observing the mechanical characteristics of interface between earth and structural member is composed of the earth container carriage with organic glass window, normal boundary control unit put on structural plate on the earth, data acquisition system, and hydraulic loading and control system. Its advnatages are high test and measuring precision, and use of digital photography.

The invention relates to a soil dynamic characteristic test technique for geotechnical engineering and especially relates to a simple instrument and a method for test of an internal stress of a soil mass under cyclic loading. A large quantity of researches and reports record that the roadbed soil under the cyclic loading is suffered from dynamic stress accumulation, but the academics does not pay attention to the phenomenon. The simple instrument can be mainly used for measuring the response conditions of the internal stress in the soil on factors such as different cyclic loading magnitudes, loading waveforms, loading frequencies and soil compaction rate, and acquiring the parameters, such as settlement curve, dynamic elastic modulus, total deformation modulus, static elastic modulus, of the soil mass under the cyclic loading effect. The method provided by the invention belongs to an innovative technology which is simple in laboratory test and convenient in soil dynamic characteristic acquisition; with the help of a lever pressure meter, the instrument can realize 10-times load output and can save instrument consumable materials and power sources; a computer system can be utilized to realize the automatic control on the instrument control and the data collection.

The invention discloses a method for predicting residual service life of an asphalt pavement according to fatigue-modulus comprehensive performance of a core sample. The method comprises the following steps: boring a core and sampling at a typical disease position of an asphalt pavement; determining resilience modulus of the core sample under the action of dynamic loading; determining a deformation-cyclic loading frequency curve for a core sample fatigue test; modeling to predict the residual service life of the asphalt pavement. The method further comprises a step of combining with a temperature factor to obtain the practical life of the pavement, and further comprises a step of combining with a traffic factor to obtain the practical life of the pavement. According to the method provided by the invention, the viscoelastic property of an asphalt mixture is comprehensively considered; due to the dynamic loading action, the practical stress situation of the pavement is stimulated, the modulus of different positions is analyzed and compared, the residual service of the pavement is described by a fatigue curve, quantitative residual life prediction is provided for maintenance of an asphalt concrete pavement, and randomness of the selection on pavement maintenance time for a long time can be overcome.

The invention discloses a material fatigue performance obtaining method for a sheet sample, which comprises the following steps: step 1: completing a tension-pressure symmetric cyclic loading test ofa multi-stage strain amplitude for the sheet sample under strain control to obtain a cyclic stable load-displacement curve; step 2: connecting load-displacement curve hysteresis loop tips as the cyclic load-displacement curve, and predicting a cyclic stress-strain relationship in accordance with a Ramberg-Osgood constitutive model with a cyclic load-displacement relationship; step 3: establishinga relationship between a true strain amplitude epsilon r, a stress amplitude sigma r and a measured and controlled strain amplitude epsilon eq of a fatigue source RVE by using the cyclic stress-strainrelationship as a material parameter; step 4: establishing a fatigue life estimation model according to epsilon r and sigma r to obtain the fatigue property of the material. According to the materialfatigue performance obtaining method, the material dimension limitations of the traditional fatigue performance test method are overcome, and the method does not rely on empirical formulas, and is applied to different materials and sample configurations.

The invention relates to a method for measuring load thresholds of geotechnical packing accumulated deformation states under cyclic loading. According to the method, brick walls and sand bags are adopted to construct a filling model, so as to form a testing system along with loading equipment and a displacement sensor, and a cyclic loading test is performed on the filling model, so as to obtain a changing curve of accumulated deformation with loading times; then the changing curve of segmented single loading average deformation with the loading times is obtained through calculation, and a negative power function as shown in the specification is adopted to fit, so as to obtain a relation curve of a power exponent Pi value with the change of load levels; a function relation between the Pi value and the load levels is obtained by virtue of cubic polynomial regression, and the corresponding load levels when P is equal to 2, 1 and 0 are obtained through back calculation, so as to be used as the load thresholds delta t1, delta t2 and delta t3 for distinguishing different evolution states of the accumulated deformation, wherein an experimental basis is respectively provided for design and maintenance of ballastless and ballast track bed structures of railways by the delta t1 and delta t2. The method has the advantages of convenience in model manufacturing, low cost, simplicity in operation and clear distinguishing criterion, and the obtained load thresholds are accurate and reliable.

The invention discloses a multifunctional friction and wear tester based on a pin-on-disk friction pair and a test method thereof. In the tester, a double pin-on-disk type friction pair or a single pin type friction pair can be adopted as a tested object, and the double pin-on-disk type friction pair utilizes a proportional loading rod applying load to the ends to always reliably apply load to twospecimen pins; a loading mechanism in the tester adopts a loader comprising a loading motor, a short rotating arm, a long swing arm, a slider, a linear guide way and a loading force application spring to cyclically apply load or apply constant load by adding weights; the tester can simulatively test the working condition in which a type of material specimen disk is rubbed by two types of materialspecimen pins under proportioned cyclic load or constant load, and the working condition in which a type of material specimen disk is rubbed by a type of material specimen pin under proportioned cyclic load or constant load. The structure of the tester disclosed by the invention is simple, the testing process is visual and convenient, a variety of working conditions can be simulated, a variety oftest requirements can be met, and the test cost is reduced.

A system and method for issuing load-dependent instructions in an issue queue in a processing unit. A load miss queue is provided. The load miss queue comprises a physical address field, an issue queue position field, a valid identifier field, a source identifier field, and a data type field. A load instruction that misses a first level cache is dispatched, and both the physical address field and the data type field are set. A load-dependent instruction is identified. In response to indentifying the load-dependent instruction, each of the issue queue position field, valid identifier field, and source identifier field are set. If the issue queue position field refers to a flushed instruction, the valid identifier field is cleared. The load instruction is recycled, and a value of the valid identifier field is determined. The load-dependent instruction is then selected for issue on a next processing cycle independent of an age of the load-dependent instruction.

The invention belongs to the technical field of material performance tests and discloses a system for testing high-frequency fatigue life in a high-temperature steam environment. The system comprises a test rack, wherein a steam box and a fatigue testing machine are fixedly arranged on the test rack; high-frequency cyclic loading of a fatigue sample is realized through the fatigue testing machine; the sample penetrates through the steam box; two ends of the sample are respectively and rotatably connected with the steam box in a sealed mode; a middle part of the sample is exposed in an internal environment of the steam box; the steam box comprises a steam input end and a steam output end; the steam input end of the steam box is connected with a steam generator; the steam generator is supplied with water by a water tank; an oxygen removal device is arranged on the water tank; the steam output end of the steam box is connected with a condenser; an oxygen content measuring device is connected to the condenser. The invention also discloses a related test method. The adopted steam generator can generate water vapor with stable flow. By arranging a dissolved oxygen testing device and monitoring steam temperature in real time, an operating environment of an actual member can be simulated to the greatest degree.

The invention provides a three-directional load experiment system for an airport pavement. The three-directional load experiment system comprises three sets of electro-hydraulic servo actuators, a horizontal bearing rack, a low-friction movement mechanism and a double-wheel testing device, wherein two solid tyres on the double-wheel testing device are fixed by a wheel shaft at the lower end of inner loading framework equipment; the top of the inner loading framework equipment is connected with an outer framework by an equipment guide rail; vertical and lateral 50kN electro-hydraulic servo actuators are arranged at the top and the side face of the outer framework; a loading end penetrates through the outer framework and is fixedly arranged on the inner loading framework equipment; the outer framework is located on a linear guide rail of the low-friction movement mechanism through a guide rail movement part arranged at the lower part; a 100kN horizontal electro-hydraulic servo actuator is fixedly arranged on a transverse beam between two horizontal counter-force inclined supports on the horizontal bearing rack and a loading end of the 100kN horizontal electro-hydraulic servo actuator acts on the outer framework of the double-wheel testing device. The three-directional load experiment system is used for simulating undercarriage loads and impacts, and circulating loads which are borne by the airport pavement in takeoff, landing, sliding and swerving processes of airplanes.

A method and apparatus are disclosed for approximating in real time the fracture fatigue entropy (FFE) of a metallic object subjected to cyclic loading. Such objects experience fatigue, which can lead to failure after a number of loading cycles. The disclosed invention allows for real time monitoring of the entropy increase in a metallic object under cyclic loading, and allows for removing the object from service before fatigue fracture occurs. Through use of the present invention, users may keep metallic objects in service for longer periods, because such objects may be safely taken closer to the fatigue fracture point. The invention therefore can effectively extend the useful life of many critical components and reduce downtime resulting from repair or premature replacement.

The invention discloses a method for fatigue analysis and detection by infrared thermal image, circularly loading test piece with different load levels, where the load is increased from low to high, the lowest load is not less than the minimum load value which makes the test piece raise temperature, and at each load level, number of circularly loading times is greater than that of circularly loading times which makes the test piece stably raise temperature, using the infrared thermal imager to measure surface temperatures at different times under different loads, processing the obtained data and obtaining two straight lines of different slopes, where the abscissa value corresponding to their intersection is fatigue limit of the test piece. And its analyzing result is more accurate and has wider application range.

The invention discloses a multifunctional comprehensive tester for testing mechanical characteristics of deformation of pavements and decks, which belongs to the test equipment of mechanical properties. The multifunctional comprehensive tester mainly comprises a supporting stand, a controllable temperature area, a vertical loading system, a vertical load boundary balancing system, a mechanical crank connecting rod circulatory loading system, a loading displacement sensor and an integrated control display system. The time variations of loading and deforming are recorded after the test begins. The multifunctional comprehensive tester can partially load indentation tests and partially load creep tests, and can do partial cyclic loading test through utilizing the vehicle load which is generated by the mechanical crank connecting rod circulatory loading system and is simulated and repeatedly acted by harmonic load. The multifunctional comprehensive tester can finish multinomial system tests without changing a cramping apparatus, can fully obtain the relative dynamic-static mechanical properties of pavements and decks, anti deformation capacity index and important parameter C, phi of anti-shearing property of material, and can solve the problem that a deformation stability integrated test and comprehensive evaluation can not be done on engineering sites.

The invention relates to a test system for simulation of long-term cyclic loading effect. The test system comprises a long-term cyclic loading device, a mold tank, a vertical cyclic loading matching device and a horizontal cyclic loading matching device. The mold tank is filled with soil for the test and a mold base is embedded in the soil body for the test. Through the long-term cyclic loading device and the vertical cyclic loading matching device, a vertical cyclic loading simulation test is realized. Through the long-term cyclic loading device and the horizontal cyclic loading matching device, a horizontal cyclic loading simulation test is realized. Compared with the existing test system, the test system has a wide application range and high simulation precision, beaks through the limitation of only vertical and horizontal single-direction loading function of the existing test system, realizes simulation of vertical and horizontal cyclic loading conditions, and has accuracy self-balance function and long-term cyclic loading function.