120 results about "Constant load" patented technology

According to the multi-parameter monitoring method and device for the material stress corrosion test, the flow rate, temperature and ion concentration of corrosive liquid are adjusted in real time through closed-loop control, and the real service environment of a material is simulated; in combination with a constant strain rate and constant load mixed loading mode, loading parameters are dynamically adjusted according to material failure and environment change, and the behavior of deviating from real failure is avoided. Electrochemical, mechanical and corrosion environment data are synchronously collected, a ridge regression algorithm is utilized to fuse multi-modal features, a Granger causal test and mutual information entropy are combined to analyze a corrosion-mechanical-environment interaction effect, and early-stage tiny damage is captured. And calculating the number of residual cycles, generating a three-dimensional probability cloud picture to quantify a failure risk level, and realizing dynamic regulation and control through a grading strategy instead of traditional fixed threshold judgment. According to the method, the real-time performance, the reliability and the automation level of stress corrosion testing are remarkably improved, and a systematic solution is provided for deep exploration of a material failure mechanism in a complex service environment.

The invention provides a bridge structure monitoring system and method combined with active early warning, and the method comprises the steps: obtaining dynamic stress data and static stress data of each bridge monitoring point in a bridge section, and constructing a plurality of fatigue stress spectrums according to the dynamic stress data of each bridge monitoring point; determining a damage accumulation coefficient of a bridge structure at each bridge monitoring point according to a stress distribution difference between the fatigue stress spectrums, and extracting a plurality of monitoring key points by combining all the damage accumulation coefficients with dead load characteristics of a bridge section; determining the rigidity of the bridge structure corresponding to each monitoring key point according to the static stress data of each monitoring key point, and determining a confidence interval for performing active early warning on the structural damage of the bridge section according to all the rigidity of the bridge structure; and performing structural damage early warning on the bridge section based on the confidence interval and the current bridge stress at each bridge monitoring point. Accurate early warning of bridge structure damage can be realized under the influence of multi-dimensional load response.

The invention belongs to the technical field of ship bearings, and particularly relates to a ship bearing radial loading test bench and method for simulating ice load and water immersion working conditions, and the method comprises the steps: installing a to-be-tested intermediate bearing on a test platform, enabling the intermediate bearing to sleeve a test shaft, starting a cooling water circulation system to control the flow, cooling water enters a cooling water coil pipe to establish oil pool cooling circulation; a driving motor is started; a test shaft stably operates through equipment such as a reduction gearbox and the like; a dynamic pressure lubrication state is established, a radial dynamic load or a stable constant load is applied through a hydraulic loading system to simulate an icebreaking load working condition, and a simulated water body is injected into a water tank; the test conditions of the intermediate bearing in a ship immersion environment are constructed through water pressure adjustment, the temperatures of lubricating oil, a bearing bush and cooling water are monitored in real time, the loading force is adjusted through feedback data, and the performance of the intermediate bearing is judged after the test is finished. The problems that ice excitation and soaking environment simulation are insufficient and a loading structure is eccentric in the prior art are solved, and high-precision cooling and thermal stability evaluation are achieved.

The invention discloses a production method of thick-wall pipeline steel X65MS for polar regions, which adopts ultra-low carbon and high Ni + casting blank secondary cogging extreme cooling + steel plate online ultrafast cooling, breaks the component design of the conventional pipeline steel standard, solves the problem of poor drop hammer low-temperature toughness of thick-wall acid-resistant pipeline steel at-55 DEG C, and has the transverse and longitudinal yield strength of 460-560MPa, the tensile strength of 590-650MPa, the yield ratio of less than or equal to 0.80, the tensile strength of 590-650MPa and the tensile strength of less than or equal to 0.80. The uniform elongation is 10%-12%, the impact value at-55 DEG C is 400-500 J, and the drop weight at-55 DEG C is 90%-95%; when the product is soaked in an NACE solution for 96 hours in an HIC test, CLR, CTR and CSR are all 0; sSC test: four-point bending constant load nominal yield is 90%, and the sample is soaked for 720 hours, and the surface of the sample has no crack; the CTOD value of the crack tip opening displacement of the CTOD test material at-55 DEG C is greater than or equal to 0.6 mm.

The invention discloses a fault reconstruction method and device for a power distribution network, terminal equipment and a storage medium, and belongs to the technical field of power grid reconstruction, and the method comprises the steps: obtaining the power data of a fault period of the power distribution network in real time, and the number of time periods between the current moment and the fault occurrence moment; then, according to the power data and the time period number, with the purpose of minimizing the sum of the load power loss amount and the power failure cost, a line recovery optimization model and corresponding constraint conditions are constructed; and finally, under each constraint condition, solving the line recovery optimization model to obtain the line switch state of each line when the sum of the load power loss and the power failure cost is minimum, and performing fault reconstruction on the current power distribution network according to the line switch state. Through the implementation of the method and the device, the problem that the obtained reconstruction scheme is unreasonable due to the fact that the loss of the load in the power failure period cannot be accurately evaluated when the static constant load power failure loss is used for power grid reconstruction in the prior art can be solved.

The invention discloses a related quantitative analysis method and system based on steam turbine regulating valve opening disturbance, and belongs to the technical field of generator set optimization operation. Sequentially deducing to obtain a first differential equation and a second differential equation based on the steam temperature change when the steam turbine regulates the valve opening disturbance; the function relation between the enthalpy value of the once-through boiler outlet working medium and the temperature and the pressure is established, and a quantitative analysis equation of the steam turbine adjusting valve opening disturbance to the once-through boiler outlet steam temperature is deduced; based on the proportional relation between the first-stage front steam pressure of the steam turbine and the front steam pressure of the adjusting steam valve and the load constant condition of the once-through boiler, a quantitative analysis equation of the opening disturbance of the adjusting steam valve of the steam turbine to the first-stage front steam pressure of the steam turbine is deduced. Through a reasonable simplified formula, the quantitative influence result of the opening degree change of the steam turbine adjusting valve on the outlet steam temperature of the once-through boiler and the first-stage front steam pressure of the steam turbine can be rapidly and accurately obtained, operation personnel can be assisted in optimizing operation, and then safe and economical operation of a generator set is guaranteed.

The invention discloses a robot joint module service life detection device, and relates to the technical field of joint module detection, the robot joint module service life detection device comprises a detection table, the top end of the detection table is provided with a connecting assembly, and the output end of the connecting assembly is provided with a torque applying and detecting assembly used for carrying out torque loading and detection on a joint module; a radial force applying and detecting assembly is arranged on one side of the outer wall of the connecting assembly and used for applying and detecting radial force to the joint module; the connecting assembly comprises a joint module body and a welding fixing frame base of the joint module body, an output flange is fixedly installed at the output end of the joint module body, a connecting flange is fixedly installed at one end of the output flange, and a torque sensor is fixedly installed at the other end of the connecting flange. A pressure sensor is mounted on one side of the outer wall of the output flange; the variable load test is carried out on the radial force and the rotating torque, the constant load can be realized, the variable load test can be realized at the same time, compared with the traditional constant load test, the stress state of the joint module in the actual work can be reflected more truly, and the service life detection result has higher reference value.

A microgrid controller of a microgrid includes a communication interface configured to receive load information corresponding to a current load demand of a plurality of loads connected to the microgrid and output control signals for controlling energy resource systems associated with the microgrid, which include a non-stabilizing group and a stabilizing group; and one or more processors, coupled to the one or more memories, configured to execute a load stabilization algorithm to generate the one or more control signals based on the load information. Executing the load stabilization algorithm includes generating, based on the load information, one or more first control signals to dynamically control an amount of total output power provided by the stabilizing group to a power distribution network of the microgrid in order to stabilize one or more cyclic loads on the power distribution network and to maintain the non-stabilizing group at a substantially constant load.

The invention relates to physical sample preparation equipment and method for an inner wall eccentric wear sleeve, and the physical sample preparation equipment for the inner wall eccentric wear sleeve comprises a rotatable main shaft, and the outer side wall of the main shaft is sleeved with a grinding wheel structure; the sleeve is arranged on the outer side of the main shaft in a sleeving mode, and the axial direction of the sleeve is parallel to the axial direction of the main shaft; the first driving device is connected with the main shaft and can drive the main shaft to rotate; the second driving device is connected with the sleeve, can drive the sleeve to move in the radial direction so as to make contact with the grinding wheel structure, can apply a preset constant load to the sleeve, and can further drive the sleeve to continue to move in the radial direction in the process that the sleeve makes contact with the grinding wheel structure to generate frictional wear; and the sleeve and the grinding wheel structure are kept in a contact state under the action of the preset constant load, so that an eccentric wear groove is formed in the inner wall of the sleeve. According to the invention, the problem of lack of preparation of an eccentric wear sleeve material sample with a crescent-shaped inner wall in the prior art can be solved.

The invention relates to the technical field of ocean information, and discloses a digital test system and method for an underwater power source, and the system comprises an umbilical cable unit which is used for connecting a variable-frequency power supply and a motor; the generator is connected to the output end of the hydraulic system; the control platform is used for acquiring real-time data related to the underwater power source and simulating the overall system performance of the power source system under a constant load working condition and a load sudden change working condition; the method is also used for determining the adjustment mode of the umbilical cable unit in the simulation process. According to the invention, the overall system performance of the underwater power source under the load sudden change working condition can be tested and verified.

The invention provides an ammonia hydrogen energy structure material constant strain rate and constant load stress corrosion synchronous monitoring platform based on acoustic emission and an implementation method thereof. Comprising a gas supply and pressurization system, a constant strain rate and constant load stress corrosion synchronous test system, a gas leakage safety control system, an acoustic emission and digital image correlation (DIC) technology online monitoring analysis system, a temperature control system and a computer integrated analysis system. In-situ dynamic analysis of stress corrosion crack propagation is realized in combination with a DIC technology; the temperature control system realizes accurate temperature control on the corrosion test reaction kettle through an independent temperature control module; the computer integrated analysis system processes multi-source data, and establishes dynamic mapping between acoustic emission characteristic parameters and corrosion crack growth rate. The platform solves the problems of off-line monitoring, single loading mode and the like of a traditional corrosion test, captures a corrosion-induced crack propagation process in real time, improves test efficiency and analysis comprehensiveness, and provides powerful support for research on corrosion behaviors of ammonia hydrogen energy structural materials.

The invention discloses a production method of heat treatment type thick-specification acid-resistant pipe fitting steel X65MS, aims to solve the bottleneck of difficult drop hammer performance of thick-wall pipe fitting steel and the difficult problem of softening after heat treatment of a pipe fitting, adopts a low-carbon, low-manganese and high-chromium microalloy component system, and is matched with a production process of large-section ultralow-temperature steel burning, temperature gradient rolling and subcritical quenching, so that the heat treatment type thick-specification acid-resistant pipe fitting steel X65MS is obtained. The high-strength thick-wall anti-acid pipe fitting steel capable of keeping the drop hammer performance is obtained, the heat treatment performance after a steel plate pipe is manufactured can reach the yield strength of 470-570 MPa, the tensile strength of 600-660 MPa, the yield ratio of less than or equal to 0.85, the impact value of minus 40 DEG C of 400-500 J and the drop hammer of minus 40 DEG C of 85-92%, and an HIC test is that CLR, CTR and CSR are all 0 after the steel plate pipe is soaked in an NACE solution for 96 hours; when four-point bending constant load nominal yield is 90% and soaking is performed for 720 hours, no crack appears on the surface of the sample.

The invention discloses a method for rapidly determining a critical stress value of metal stress corrosion cracking, and belongs to the technical field of metal material corrosion and protection. According to the invention, the critical stress value can be directly and rapidly measured instead of a sensitivity coefficient evaluation index obtained by a conventional stress corrosion test, the sample number and the test period can be obviously reduced, the double-truncated-cone-shaped sample is designed and processed, and the cross section of a single truncated cone of the sample is linearly decreased from one end to the other end; and the continuous stress gradient generated when the constant load is applied is accurately controlled. A stress corrosion test is carried out in a corrosive medium through a constant load method, and a critical stress value of stress corrosion cracking of the material in a corrosive environment is measured according to a loaded load and the maximum cross section area of cracks generated in the double-circular-truncated-cone-shaped sample. By utilizing the method, the stress corrosion cracking critical stress values of different metal materials can be efficiently and quickly measured, so that a basis is provided for section design and allowable load of engineering components and medical instruments.

The application provides a cement industry load production optimization scheduling method considering the adjustability of a rotary kiln, and belongs to the technical field of cement industry load production optimization scheduling; in order to solve the defects that the rotary kiln is generally regarded as a constant load and the adjustable potential is ignored in the existing cement industry load, the technical scheme is that: the rotary kiln is modeled by combining mechanism and data, the adjustability is verified, and a mechanism model of the coupling relationship between the rotary kiln temperature and the materials of the front and rear production links is constructed on the basis of energy conservation and mass conservation; then, the model parameters are identified by using the historical operation data of the rotary kiln, and the mechanism interpretability and data accuracy are considered; finally, the whole cement production process is summarized as multiple continuous links by taking a state task network as a framework, each link corresponds to a node, and the cement industry load production optimization scheduling is realized through material balance, start-stop and storage constraints; the application is applied to cement production control.

The invention relates to the technical field of testing, and provides an actuator loading testing device which comprises a hydraulic oil cylinder, a reversing valve, a hydraulic pump, a motor, a first ball valve, a second ball valve, a proportional overflow valve, an electromagnetic overflow valve and a controller. The controller is used for controlling the first ball valve, the second ball valve, the reversing valve, the electromagnetic overflow valve or the proportional overflow valve according to the oil inlet and outlet pressure of the first cavity A and the second cavity B of the hydraulic oil cylinder so as to test the actuator. The device not only can carry out a tension test of the actuator, but also can carry out a thrust test of the actuator, not only can carry out a variable and constant load test of the actuator, but also can keep the load force unchanged when the actuator moves so as to carry out a constant load test of the actuator and cover a full working condition test of the actuator, and the whole device is loaded by a hydraulic system, so that the test efficiency is improved. High load can be obtained by increasing system pressure, and the whole device is safe and reliable.

To provide an adhesive composition which is excellent in 180-degree peel adhesive force, constant load holding power and shear retention force among adhesive characteristics and has high removability and to provide an adhesive tape having an adhesive layer composed of the adhesive composition.SOLUTION: In order to exhibit favorable adhesive properties in an adhesive composition, it is crucial to adjust the dynamic viscoelasticity of the adhesive composition among various physical properties and it was found that the storage modulus G' strongly correlates with shear holding force performance and tanδ strongly correlates with constant load holding power performance. Specifically, it is necessary for the storage modulus G' at a constant temperature to be above a certain value in order to achieve an adhesive layer having excellent shear retention force and it was found that it is necessary for the tanδ at a constant temperature to be equal to or above a certain value in order to achieve an adhesive layer having excellent constant load holding power.SELECTED DRAWING: None

The present invention belongs to the technical field of material mechanical property testing, and discloses a method for testing the thermomechanical fatigue crack propagation of metal materials. First, the functional relationship between the crack length and the flexibility of the sample, as well as the functional relationship between the crack propagation driving force and the crack length are obtained by the finite element method; then, a crack is prefabricated using the constant load method under normal temperature conditions, and a thermomechanical fatigue crack propagation test is performed to obtain the test results; finally, the crack length corresponding to each cycle of the metal sample is calculated by the improved flexibility method, and the crack propagation rate is calculated in combination with the functional relationship between the crack propagation driving force and the crack length. The present invention can effectively simulate the working conditions of variable temperature and alternating load coupling that high-temperature components are subjected to during service, obtain the specific crack propagation rate and the evolution of the plastic zone in the crack propagation area, and provide important experimental data and theoretical basis for the damage tolerance design and safety verification of high-temperature structures under severe working conditions.

A kind of thick-wall acid-resistant pipeline steel X65MS hot rolling process method, the chemical composition of steel is as follows: C=0.03%~0.04%, Si=0.2%~0.4%, Mn=1.0%~1.2%, Cr=0.2%~0.4%, Cu=0.2%~0.3%, Ni=0.1%~0.4%, Mo=0.10%~0.25%, Nb=0.03%~0.04%, Ti=0.01%~0.015%, Ce=0.004%~0.006%, S≤0.004%, P≤0.008%, the balance is Fe and inevitable impurities;Production is carried out using continuous casting billet with thickness of 360mm and above, and the finished product thickness is 40~55mm;Three-stage rolling process and the matched intermediate billet cooling and post-rolling ultra-fast cooling process are used, the obtained pipeline steel has CLR≤10%, CSR≤1%, CTR≤1% in hydrogen-induced cracking (HIC) experiment under the condition of NACE solution immersion for 96 hours;In sulfide stress corrosion cracking (SSCC) experiment, no crack is found under the condition of four-point bending constant load nominal yield of 90% for 720 hours.

The utility model provides a one-dimensional dead load consolidation test device which comprises a cylinder body with two open ends, a bottom plate is arranged at the bottom end of the cylinder body, a pressing block is arranged in the cylinder body in a sliding mode, the top face of the pressing block is horizontally connected with a limiting rod, and the two ends of the limiting rod extend outwards to the outer side of the pressing block. Limiting grooves suitable for the two ends of the limiting rod to slide are vertically and downwards formed in the two sides of the barrel, external threads are formed in the periphery of the upper portion of the barrel, a fixing ring located on the upper portion of the limiting rod is arranged on the external threads in a sleeving mode, and a plurality of drainage holes are formed in the pressing block and the bottom plate at intervals. The test device is simple and easily available in material, low in cost, convenient to operate and easy to master, can realize that the unloading phenomenon does not occur in the soil sample solidification and nuclear magnetic resonance test process, obtains more scientific soil sample pore structure information, and is convenient for scientific research and engineering application.

The present application relates to compressor online detection technical field, provide a kind of compressor online detection equipment and compressor online detection method.The compressor online detection equipment includes: stabilized power supply, with the compressor to be measured is connected;Suction stabilized component is connected in the suction pipeline of the compressor to be measured, for adjusting the suction pressure of the compressor to be measured;Exhaust stabilized component is connected in the exhaust pipeline of the compressor to be measured, for adjusting the exhaust pressure of the compressor to be measured, so that the compressor to be measured has exhaust pressure constant load operating phase;And acquisition device, with the compressor to be measured is connected, for acquiring the operating parameter of the compressor to be measured in the load operating phase.The present application can realize the flexible, stable, accurate detection of the operating parameter of the compressor to be measured, meet the test demand of the compressor to be measured.

The present application relates to the technical field of plate performance testing, and particularly relates to a kind of plate edge durability test method;It comprises the following steps: cutting plate sample into standard size test piece;Using thermal mechanical analyzer respectively test the linear expansion coefficient of test piece edge material and base material;The test piece after processing is placed in environmental test chamber and is subjected to cyclic test;Test piece is fixed on load testing device, and constant load is applied along the direction perpendicular to the edge interface of plate plane;Using flatness tester to measure the overall warping of test piece, compare with the warping data before testing, calculate the warping change, evaluate the actual effect of plate balanced laminating process on preventing warping after edge sealing;Using weighted scoring method to calculate the comprehensive score of edge durability;Realize that the long-term durability of plate edge sealing under complex working conditions can be comprehensively and accurately evaluated, and provide scientific and comprehensive technical support for edge sealing process optimization, material selection and structure design.

The utility model relates to a high-speed precise bearing dynamic stiffness measuring device, and belongs to the technical field of bearing dynamic stiffness measurement. A fixing plate of the device comprises a mounting ring and a base, the mounting ring is of an annular structure formed by combining an upper semicircular ring and a lower semicircular ring in a split mode, the lower semicircular ring is located at the top of the base and integrated with the base, and the mounting ring is arranged on a main connecting annular plate in a sleeving mode and clamps and fixes the main connecting annular plate through the mounting ring. The thrust electric cylinder is connected with the main connecting annular plate through a connecting plate; the front end of the thrust electric cylinder extends into an inner cavity of the main connecting annular plate, the spherical floating push head and the force measuring sensor are sequentially assembled at the front end of the thrust electric cylinder, and the bearing push plate is arranged between the floating push head and the test bearing on the rotating mandrel. The device is used for measuring the dynamic stiffness of the high-speed precise bearing, and can realize the measurement of the dynamic stiffness of the bearing in various coupling forms such as variable load, variable speed, constant load, constant speed and the like by controlling the rotating speed of the motor and the thrust of the thrust cylinder.

The invention belongs to the technical field of electric actuator testing, and particularly relates to an electric actuator load durability testing system and a testing method.The electric actuator load durability testing system comprises a workbench, and the top surface of the workbench is fixedly connected with a top plate through a supporting rod; the transmission assembly is arranged on the workbench; the first connecting part is arranged on the top surface of the workbench; the first connecting part is arranged on the top plate, the second connecting part is arranged on the top plate, and clamping parts are annularly distributed on the first connecting part and the second connecting part; the linkage part is arranged at the upper end of the transmission assembly; and the load assembly comprises a first load part and a second load part which are arranged on the workbench, and a pressure applying part is further arranged on the first load part. According to the invention, the test requirements of a linear motion actuator and a rotary motion actuator can be simultaneously met, and various load simulation functions including constant load, gradually increased load, impact load and the like are realized.

A microgrid controller of a microgrid includes a communication interface configured to receive load information corresponding to a current load demand of a plurality of loads connected to the microgrid and output control signals for controlling energy resource systems associated with the microgrid, which include a non-stabilizing group and a stabilizing group; and one or more processors, coupled to the one or more memories, configured to execute a load stabilization algorithm to generate the one or more control signals based on the load information. Executing the load stabilization algorithm includes generating, based on the load information, one or more first control signals to dynamically control an amount of total output power provided by the stabilizing group to a power distribution network of the microgrid in order to stabilize one or more cyclic loads on the power distribution network and to maintain the non-stabilizing group at a substantially constant load.

The invention discloses a linear output steering engine constant load loading device, and belongs to the technical field of steering engine loading, the linear output steering engine constant load loading device comprises a loading rack and a rotating member, the loading rack is provided with a loading surface, and the loading surface is provided with a rotating support frame and a steering engine fixing frame. And a mounting cantilever is arranged at the end part of the rotary support frame. The steering engine fixing frame is fixedly installed on the loading face, and the shell is adjustably installed on the steering engine fixing frame. The rotating component comprises a balance rotating arm, a rotating shaft rotationally connected to the installation cantilever is arranged at the gravity center position of the balance rotating arm, a rocker arm is arranged at the end of the rotating shaft, and the output end is adjustably installed at the end of the rocker arm and is perpendicular to the rocker arm. The balance rotating arm is provided with a load assembly. The linear output steering engine constant load loading device provided by the invention is simple in structure and convenient to use, not only can apply a constant load to a steering engine, but also can conveniently realize adjustment of the load of the steering engine, and can reduce energy consumption while ensuring that the load of the steering engine is stably applied.

This invention discloses a simulation method, apparatus, equipment, and medium for an electromagnetic railgun. Compared to constant load parameter values, it employs a finite element method combined with equivalent circuit analysis. The rail is divided into N segments, and the armature is positioned at the end of the i-th segment. The current equivalent load parameters of the rail are updated based on the circuit parameters at each discrete time point, thereby approximating the true value of the equivalent load parameters segment by segment. The current equivalent load parameters are then substituted into the circuit and mechanical equations to calculate the discrete data when the armature is positioned at the end of the i-th segment. If i < N, let i = i + 1, and iterate the above simulation steps; if i = N, then fit all the calculated discrete data between the armature velocity and discrete time points to obtain continuous data between the armature velocity and time. It is evident that this invention corrects the equivalent load parameters whenever the armature moves a certain distance, thus simulating an electromagnetic railgun firing process that more closely approximates the real situation.

The invention discloses a method for controlling the fatigue life of a forged aluminum alloy hub, and belongs to the technical field of automobile hub manufacturing. The method is characterized by comprising the following steps: 1) under the conditions that the action of other external forces on a hub is not considered and the loading of a load spectrum is constant, the fatigue life of the hub is controlled by controlling an applied load according to real stress and controlling the amplitude of the real stress and a constant load ratio; and 2) according to fatigue simulation of the forged aluminum alloy hub, directly determining the relationship among the real stress amplitude delta sigma, the load ratio R and the fatigue life N. The method has the advantages that the fatigue life of the forged aluminum alloy hub can be controlled by controlling the actual stress amplitude and the application of the load ratio, the fatigue life is calculated according to the actual stress amplitude and the load ratio, the fatigue life of the forged aluminum alloy hub is accurately controlled, and the anti-fatigue performance of the forged aluminum alloy hub is effectively controlled.

The present invention provides a calculation method, device, equipment and storage medium for a tie-strut rigid frame arch bridge, which relates to the technical field of large-span rigid frame arch bridges. The method includes obtaining initial information, which is the side span length dimension, comparing the initial information with a first preset threshold and a second preset threshold, and determining it as a tie-strut rigid frame arch bridge when the initial information is greater than the first preset threshold and the initial information is less than the second preset threshold; obtaining first information, which includes self-weight thrust and second-phase constant load thrust increment; obtaining second information based on self-weight thrust, second-phase constant load thrust increment and a preset load distribution coefficient, which is strut thrust resistance; obtaining the number of struts based on strut thrust resistance and a preset single strut load. The present invention clarifies a load distribution method for tie rods and struts in a tie-strut rigid frame arch bridge, which facilitates the determination of the set number of struts.

To provide a hot-melt type adhesive composition which is excellent in 180-degree peel adhesive force, constant load holding power and shear retention force among adhesive characteristics and has high removability and to provide an adhesive tape having an adhesive layer composed of the adhesive composition.SOLUTION: There is provided a hot-melt type adhesive composition which comprises at least an acrylic block copolymer (X), an acrylic block copolymer (Y) and a tackifier resin (Z), wherein the acrylic block copolymer (X) has a weight average molecular weight (Mw) of 50000 to 400000 and is liquid at 23°C, the acrylic block copolymer (Y) has a weight average molecular weight (Mw) of 100000 or less and is liquid at 23°C and the tackifier resin (Z) has a softening point of 110°C or more.SELECTED DRAWING: None

The invention discloses a hydrogen environment metal material constant load testing device and a CTOD-based testing method.The high-pressure gas storage bin in the device is connected with an upper bin cover and a lower bin cover in a sealed mode, the upper bin cover is provided with a gas inlet pipeline, the lower bin cover is provided with a gas outlet pipeline, the high-pressure gas storage bin is filled with hydrogen, the upper bin cover is provided with an upper loading rod, and the upper loading rod is provided with a lower loading rod; the upper end of the upper loading rod is connected with a mechanical testing machine loading head, the lower end of the loading rod extends into the high-pressure gas storage bin, a load sensor is installed on the upper loading rod in the high-pressure gas storage bin, a lower loading rod is arranged on the lower bin cover, the upper end of the lower loading rod extends into the high-pressure gas storage bin, and the lower end of the lower loading rod is connected with a mechanical testing machine base. A constant-load sample is connected between the upper loading rod and the lower loading rod, an extensometer is mounted on the constant-load sample, and a temperature sensor and a pressure sensor are mounted in the high-pressure gas storage bin. The device can effectively provide a high-pressure hydrogen test environment, the method is not limited by the wall thickness of the pipe, and the fracture toughness value of the sample in the hydrogen environment is obtained.