47results about How to "In line with the actual situation of the project" patented technology

The invention discloses a method for predicting service life of a product by an accelerated degradation testing based on degradation distribution non-stationary time series analysis. The method comprises the following steps of: 1, acquisition and preprocessing of test data; 2, parameter estimation of degradation distribution; 3, time series modeling of degradation distribution parameters; 4, accelerated degradation modeling based on the degradation distribution; and 5, service life prediction based on degradation distribution. The method can macroscopically describe degradation statistical regulation of all samples under accelerated stress, overall analyze the time series of the degradation distribution in an accelerated degradation process, can extrapolate the degradation distribution under the accelerated stress to normal stress to obtain product reliability reflecting the product accelerated degradation random process volatility regulation and service life relationship prediction, improve the credibility on estimation result of service life prediction and reliability, and save more time and is more efficient compared with performance degradation prediction under normal stress level.

The invention provides a dynamics performance parameter optimizing method of a high-speed train, relates to the field of parameter design optimizing based on the dynamics simulation analysis of the high-speed train, and aims at effectively replacing a dynamics simulation model of the high-speed train by a comprehensive target neural network agent model and combining the design analysis and the multi-target optimization algorithm of the high-speed train in the multi-disciplinary field to analyze and optimize the dynamics simulation approximation model of the high-speed train. The method specifically comprises the steps of building a multi-rigidity dynamics simulation model for the high-speed train; determining related important input / output design spaces; selecting sampling strategy to obtain a design space sample set suitable for the dynamics performance analysis of the high-speed train; improving the generalization accuracy of the comprehensive target neural network by the bayesian regularization method; adjusting the number of nodes in a hidden layer to build the comprehensive target neural network agent network model of which the error is controlled to be within a certain of range; performing multi-target optimization through the intelligent differential evolution algorithm by using the improved comprehensive target neural network agent network model to obtain the optimized high-speed train design parameters. The method is mainly applied to the dynamics analysis and design optimization of the high-speed train.

The invention discloses an experimental method for top plate seepage and water inrush when in underwater exploitation as well as an apparatus thereof, comprising the steps of: (1) putting a configured experimental material in a model box according to the practical relative position; (2) exerting lateral pressure on the model material in the model box; (3) sealing the top part of the model box and exerting the stated water pressure on the top part of the model; (4) acquiring water pressure data, tectonic stress data, displacement digital photos and crack digital photos magnified by certain times at regular intervals in the exploitation process until the water inrush destruction takes place; (5) repeating the steps of (1), (2) and (3) to change lateral pressure and water pressure parameters, and repeating the step (4); and (6) obtaining the relation between the water pressure at the top part, the tectonic stress and the model surface displacement, model surface crack. The method and apparatus can embody the combined action of tectonic stress and water pressure at the top part and deadweight function of cover layer more factually, thereby improving the testing precision.

The invention provides a step stress acceleration performance degradation reliability analysis method considering a measurement error. The method comprises the steps that acceleration performance degradation test data of step stress of all samples is collected through an acceleration performance degradation test, and the acceleration performance degradation test data is preprocessed; a performancedegradation process of a product is described based on a generalized Wiener process, an acceleration degradation model is determined, and a step stress acceleration performance degradation model considering the measurement error is established; a likelihood function is utilized to estimate unknown parameters in the step stress acceleration performance degradation model; and reliability assessmentand life prediction are performed on the product. Through the method, the measurement error is introduced into step stress acceleration performance degradation data analysis for the first time, different time-varying characteristics of mean value items and variance items are considered, and the method better conforms to engineering actual conditions; and through sufficient development and utilization of vertical information of the degradation data under different stress levels and horizontal information of different samples, the amount of the information is effectively increased, and reliability assessment precision is improved.

The invention provides a soft-hard interbedded wall rock tunnel construction simulation method considering bedding action, comprising the steps of S1, acquiring related physical parameters of wall rock: processing tunnel wall rock to be simulated into a standard test piece according to Regulation for Testing of Physical and Mechanical Properties of Rock by using rock conventional mechanical property test, and acquiring related physical parameters of wall rock through uniaxial / triaxial compression test and shear test; S2, imparting a wall rock simulation unit to the mechanical parameters acquired by the tests of step S1, and carrying out simulation analysis by using self-contained elastic-plastic constructive model of ANSYS software, dp rules and contact pair effect. The simulation method provided herein enables the simulation for changes and influences generated by bedding stress field, displacement field and the like in the whole process of soft-hard interbedded wall rock tunnel excavation, the problem that nonlinear analytical results fail to converge in the simulation process is solved, simulation results may indicate that whether bed separation and the like occur after tunnel excavation, the simulation better meets the engineering actuality, and the simulation results may guide actual tunnel construction.

The invention discloses a paste filling material laboratory curing method for simulating an actual stope environment. The method comprises: (1) carrying out on-the-spot investigation on an actual stope and carrying out real-time monitoring in the actual stope after paste filling, (2) preparing a filling body test piece in a laboratory, (3) placing the filling body test piece in a transparent container, pouring a corrosion solution into the container, then placing the container with the solution in a pressure frame, putting the pressure frame into a concrete carbonization test box, adjusting concrete carbonization test box conditions according to actual stop field monitoring values and carrying out synchronous maintenance on the filling body, (4) according to the actual stop field monitoring stress, applying stress to the filling body test piece through the pressure frame, and (5) taking out the filling body test piece after maintenance and testing mechanical properties. The mechanicalproperties detected by the method are closer to those of the filling body in the actual engineering and satisfy the actual conditions of the project.

The invention discloses a testing method of a single-pile multi-directional horizontal bearing force under combined loading effect. The method comprises the following steps: (1) determining the size of a test pile, soil distribution and thickness; (2) determining a vertical loading value and a loading level, and a horizontal loading value and a loading level; (3) paving soil in layers; (4) determining loading direction and quantity of horizontal loading; (5) mounting horizontal loading pile caps; (6) placing a horizontal loading system; (7) placing a vertical loading system; (8) mounting a data acquisition system; (9) determining multi-directional ultimate bearing capacity of the test pile for single time; (10) detaching the test device and recycling soil samples for testing; (11) determining horizontal bearing capacity characteristic values of a single pile under different vertical loading; (12) determining the horizontal ultimate bearing capacity of the single pile under different vertical loading; The method has a good effect, is convenient to operate and low in cost.

The invention relates to a fault diagnosis system sensor optimal configuration method based on a quantitative structure model. The method comprises the following steps: 1) establishing a structure model of a fault diagnosis system through a structure analysis method, wherein the structure model is represented by two matrixes, that is an analytical redundant relation matrix and a fault feature matrix, and the structure model can qualitatively describe the fault diagnosis system; 2) detecting nondeterminacy with the structure model of the fault diagnosis system and sensors being combined to obtain quantitative description of the fault diagnosis system and realize the purpose of quantitatively analyzing the fault diagnosis system, and establishing a calculation formula for fault diagnosis system key performance indicators with the detection of nondeterminacy being taken into consideration; 3) establishing a sensor optimization model of the fault diagnosis system; and 4) solving the optimization model through a genetic algorithm. The sensor optimal configuration method for the fault diagnosis system can effectively save the cost of the sensors of the fault diagnosis system, and the configuration result accords with engineering practice situations better.

The invention discloses a move distance calculation method of an existing railway curve. An improved PSO (particle swarm optimization) method is adopted for optimizing radius and transition length of a design curve, and then movement distance of each measuring point is calculated. In the optimization process, a minimum quadratic sum or minimum absolute value sum of movement distance values delta i of the measuring points serve as an objective function. The move distance calculation method of the existing railway curve is capable of reducing dependence on an initial value and is high in adaptability.

The invention relates to a power cable reliability estimation method based on a time varying stress-intensity interference model. The method includes power cable cumulative degradation model establishment, power cable cumulative degradation and cumulative degradation threshold rate distribution parameter acquisition, power cable time varying stress-intensity interference model establishment and power cable reliability estimation based on the time varying stress-intensity interference model establishment. The power cable cumulative degradation model establishment and the power cable cumulative degradation and cumulative degradation threshold rate distribution parameter acquisition are performed firstly, the power cable time varying stress-intensity interference model is established, and the reliability of medium-high voltage cables can be estimated through the power cable time varying stress-intensity interference model; by the aid of the method, the problems that the accuracy and reliability of the power cable reliability estimation are low in the prior art are solved effectively, the medium-high voltage cable state estimation is more scientific and meets the actual engineering conditions better, and the high practical significance is provided.

The invention discloses a high-dam rock mass unloading relaxation evaluation method based on fusion test and monitoring data mining. The method comprises the following steps that 1, based on differentdegrees of mass reduction of rock masses at different depth positions, the relationship between a longitudinal wave velocity change coefficient in a non-columnar joint rock mass and the influence onthe mass of the rock mass is determined; 2, in combination with the indoor test of an acoustic wave test system, the relationship between the longitudinal wave velocity change coefficient in the rockmass after excavation of a columnar joint rock mass and the influence on the mass of the rock mass is determined; and 3, factors such as lithology, a structural surface and a protective layer are introduced, and the relaxation depth evaluation method of an untested area after the dam foundation excavation is established. The method considers the influence of engineering rock mass lithology, structural surface exposing, excavation measures and the like on the unloading relaxation depth after rock mass excavation, is more scientific and better meet the engineering practical situation. The evaluation method can provide an evaluation criteria for the excavation of the high-dam bed rock mass engineering, and has quite high practicability and wide applicability.

The invention discloses a surrounding rock rapid grading method for a large-span underground cave depot. The method comprises the following steps that excavation section size data of the underground cave depot are obtained; obtaining surrounding rock classification and [BQ] y of the underground cave depot in the geological survey process; carrying out geological sketch and zoning on the excavatedsection, and respectively carrying out surrounding rock BQ value calculation on the section zoning; kv and Rc are used for correcting the cave depot span; correcting the underground water state, the structural plane occurrence and the initial crustal stress, and calculating [BQ] xz; [BQ] xz of each subarea of the section is combined with [BQ] y, the arithmetic mean value is solved, comprehensive surrounding rock grading is conducted, three-dimensional surrounding rock grading of the underground cave depot is obtained, and then subdivision and subdivision are conducted on basic surrounding rockgrading. According to the method, the influence of the size effect of the ultra-large-span underground cave depot on the compressive strength and the integrity degree of the rock is considered, so that the existing national standard surrounding rock classification standard is corrected, surrounding rock classification is more accurate, and construction is safer.

The invention discloses a power distribution network CPS safety evaluation method considering communication fault influence and a device thereof, and the method comprises the steps: constructing a physical anticipated fault set, carrying out the physical fault anticipation of a power distribution network CPS one by one, and considering the information faults in the execution process of power distribution automation fault processing services, such as fault positioning, isolation and recovery; constructing an information physical combination anticipated fault set with service correlation; quantitatively analyzing the influence of the communication fault on the execution process of the distribution automation service, and calculating a corresponding safety evaluation index; and finally, sorting and screening the calculated security consequences to obtain an information physical serious fault set in a corresponding analysis scene. According to the method, the influence of the information physical combination fault on the operation safety of the power distribution network is quantitatively analyzed, and the recovery control strategy after the power distribution network fault is effectively combined in the evaluation process, so that the safety evaluation result better conforms to the engineering practical situation.

The invention relates to a testing device of single pile multidirectional horizontal bearing capacity under composite load. The testing device is characterized in that soil for simulating a site is placed in a model box, a test single pile is buried in the soil, a vertical loading system comprises standing columns, a crossbeam, a lever, a vertical loading device and vertical loading weights, one end of the lever is hinged to a rotary shaft between the two standing columns, the vertical loading device is mounted in the middle of the lever, the vertical loading device is located at the top of the test single pile, and the vertical loading weights are connected to the other end of the lever; a horizontal loading system comprises a horizontal loading pile cap, a fixed pulley, a steel wire rope and weights, the horizontal loading pile cap is mounted on the top surface of the test single pile and connected with one end of the steel wire rope, the steel wire rope penetrates the fixed pulley, the other end of the steel wire rope is connected with the horizontal loading weights, and the fixed pulley is mounted on the model box; a data collecting system comprises a displacement meter which is located on the horizontal loading pile cap and connected with a data collecting instruction. The testing device is good in effect, convenient to operate and low in cost.

The invention discloses a test method of asphalt and coarse aggregate adhesiveness. The test method comprises the following steps: preparing an asphalt cement material for test and five coarse aggregate samples meeting the requirements, measuring masses M1 to M5 of coarse aggregates by using an analytical balance, scanning the coarse aggregates by using a 3D area determinator to obtain surface areas A1 to A5, then heating and drying the aggregates, soaking the aggregates in the asphalt adhesive which is pre-heated to a flowing state, so that the coarse aggregates can be taken out after being sufficiently coated with the asphalt adhesive; and curing an asphalt membrane on the surface of the aggregate, gradually lifting the sample by using a wire, after the sample is completely solidified, placing the sample into a self-made instrument, and performing the washing and poaching test. After the test, the masses M'1 to M'5 of the sample are re-measured, and the thickness of the remaining structural asphalt membrane which can still cover the surface of the coarse aggregate sample can be calculated by virtue of the formula. By adopting the test method, the defects of the boiling method that the influence of the human factor is serious and the evaluation index is not quantified can be overcome, and the unpredictable test error of the mass loss method that the free asphalt which does notcover the aggregate is also calculated as the boiling mass loss can also be avoided.

The present invention discloses a nuclear radiation shielding material optimization design method, comprising the following steps: (1) initializing a material ratio; (2) according to the element ratio obtained in step (1), respectively calculating physical quantities of shielding properties, thermal properties, mechanical properties and etc. of characteristic materials; (3) making results of step (2) dimensionless and then calculating a weighted sum; (4) obtaining an optimized objective function value from step (3), the value being one daughter of genetic algorithm; corresponding to the material ratio adaptation characteristics, using the genetic algorithm to conduct choosing, crossing and variation to give a new material component ratio, and then repeating step (1); outputting an optimized material ratio after the objective function gets an optimum value through loop calculation. The nuclear radiation shielding material optimization design method, 1) realizes component optimization design of a plurality of materials, 2) can be easily complied to a computer program for improving searching efficiency and effectively guiding the design and production of a nuclear radiation shielding material, and 3) comprehensively takes multiple properties of materials into account, and thus is capable of optimizing and designing a novel shielding material with good comprehensive properties.

The invention discloses a straight pile vertical impedance calculation method, which comprises the following steps: vertically dispersing a pile body of the straight pile and foundation soil accordingto the horizontal layering condition of a soil body, and dispersing the foundation soil in the radial direction according to the disturbance condition of soil around the pile; solving a wave equationof each soil ring layer and calculating the dynamic stiffness on the pile-soil contact surface through a radial transfer matrix method; and calculating the vertical impedance of the straight pile through a vertical transfer matrix method after solving the equation. The straight pile vertical impedance calculation method has the advantages that the vertical impedance of the straight pile under theradial heterogeneous condition of saturated soil around the pile caused by the construction disturbance effect in the layered foundation is calculated and considered; radial heterogeneity of layeredsaturated soil under a construction disturbance effect is considered through a bidirectional transfer matrix method, and meanwhile, a fractional derivative operator is adopted to describe a stress-strain relationship of foundation soil so as to improve calculation precision; and a Rayleigh rod vibration theory is adopted to describe vertical vibration of a pile body so as to consider a transverseinertia effect of pile body vibration. By means of the straight pile vertical impedance calculation method, the calculated vertical impedance of the straight pile better conforms to engineering practice.

The invention provides a fixing device applied to tension and pressure vibration fatigue test of components. The fixing device comprises an end fixing device and a middle fixing device arranged on a vibration fatigue tester, wherein the end fixing device is fixed on two ends of the vibration fatigue tester or the end fixing device is fixed at one end of the vibration fatigue tester; a top joint of a top fixing plate of the middle fixing device is connected with a fixing joint of a frame of the vibration fatigue tester. According to the fixing device applied to the tension, compression and vibration fatigue test of the components, the overall middle fixing device is moved upwards by pulling the fixing joint of the frame of the vibration fatigue tester upwards, so that the tension fatigue test of the components is implemented; the pressure fatigue test of the components is implemented by squeezing the fixing joint of the frame of the vibration fatigue tester downwards, so that the tension vibration fatigue test and the pressure vibration fatigue test of the components are implemented; the device is more in accordance with the actual condition of engineering. In addition, the device can be adaptive to tension and pressure vibration fatigue test of the components with various section types and different sizes through corresponding adjusting mechanisms.

A method for back analysis of foundation pit base on monitoring data of lateral displacement of retain wall is provided. By comparing the monitoring value of retaining wall lateral displacement with the theoretical value of retaining wall lateral displacement in the initial stage of excavation, the new soil parameters obtained in the last excavation stage are used to predict the lateral displacement of the retaining wall in the next excavation. The prediction accuracy is improved gradually and the error between the predicted value and the monitored value of the lateral displacement of the retaining wall is small. At the same time, the method incorporates the concept of reliability design into the prediction of retaining wall lateral displacement, taking into account the variability of soilmass, which is more in line with the engineering practice. The invention has the advantages of simple calculation, strong engineering operability, and can be used by relevant design and constructionpersonnel of the foundation pit, effectively predicts the deformation of the foundation pit, and dynamically adjusts the design of the supporting structure. The invention can be programmed into simpleprogram software, and is suitable for popularizing and using.

The invention discloses an online cooperative control method for multiple reactive power compensation devices in a regional power grid. The method comprises the steps of employing a main and auxiliarycontrol mode when the reactive power compensation devices of different manufacturers or different types exist in the regional power grid; and when all reactive power compensation devices in the regional power grid are of a same model of a same manufacturer, adopting an autonomous control mode. Aiming at the cooperative operation of the plurality of reactive power compensation devices in the regional power grid, the situation of devices of the same model of the same manufacturer is considered, meanwhile, the situation of devices of different models of different manufacturers is also considered, different control strategies are respectively adopted, and the engineering practical situation is better met. According to the method, when the reactive target value which should be sent by each device is calculated, the voltage-reactive slope characteristic of the device is considered, but also the rated capacity proportion of each device is also considered, so that a more balanced reactive margin is reserved for each device. Meanwhile, the line loss optimization of the regional power grid is also considered, and the line loss is reduced while the reactive power is compensated.

The invention discloses a light-gauge steel section and foam concrete interface sliding performance testing method. The method includes the steps of 1, sample manufacturing; 2, test preparation; 3, test installation; 4, test loading and unloading; 5, interface upper and lower sliding value measurement; 6, interface sliding value determination. The defects that formerly, test measurement cannot be achieved or the measurement difficulty is large, and failure is likely to happen are overcome, a load-sliding curve can be easily drawn, reference is provided for simulation analysis of a light-gauge steel section and foam concrete combined structure, and the full process stress analysis of the steel section and foam concrete combined structure becomes possible. The testing method can be applied to the light-gauge steel section and foam concrete combined structure and similarly can be used for an interface sliding test of a common steel section and concrete combined structure. The load-sliding curve obtained through the testing method can further improve the precision of simulation analysis, and meanwhile can be used for the full process sliding analysis of a whole component.

The invention discloses a pipe top vertical soil pressure calculation method and device suitable for non-grooving pipe jacking construction. The method comprises the steps that macroscopic parameters of a soil body in a non-grooving pipe jacking construction area and the overexcavation amount of a pipe jacking machine are obtained; establishing a discrete element model according to the pipeline design parameters and the macroscopic parameters of the soil body, and carrying out numerical simulation on the soil body movement process caused by the overexcavation amount so as to determine the development height of a pipe top shear zone and the average width of the shear zone; and according to the macroscopic parameters of the soil body, the development height of the pipe top shear zone and the average width of the shear zone, the pipe top vertical soil pressure of the non-slotting pipe jacking construction is calculated. By implementing the method, the discrete element method is adopted to perform numerical simulation on the moving process of the pipe top soil so as to determine the development height and width of the pipe top shear zone. Therefore, theoretical analysis and discrete element numerical simulation are combined in calculation of the pipe top vertical soil pressure, the actual engineering situation is better met, and the accuracy of the calculation result is obviously improved compared with an existing theoretical formula or method.

The invention discloses a method for predicting service life of a product by an accelerated degradation testing based on degradation distribution non-stationary time series analysis. The method comprises the following steps of: 1, acquisition and preprocessing of test data; 2, parameter estimation of degradation distribution; 3, time series modeling of degradation distribution parameters; 4, accelerated degradation modeling based on the degradation distribution; and 5, service life prediction based on degradation distribution. The method can macroscopically describe degradation statistical regulation of all samples under accelerated stress, overall analyze the time series of the degradation distribution in an accelerated degradation process, can extrapolate the degradation distribution under the accelerated stress to normal stress to obtain product reliability reflecting the product accelerated degradation random process volatility regulation and service life relationship prediction, improve the credibility on estimation result of service life prediction and reliability, and save more time and is more efficient compared with performance degradation prediction under normal stress level.

The application discloses a method for testing the natural oxidation rate of a limestone wet desulphurization absorption tower slurry. The method comprises the following steps: preparing fire coal which can be combusted in a boiler for 5.8-6.2 hours; adjusting the boiler load to 50% of the maximum output of the boiler, and keeping the stability of the combustion working condition; stopping an oxidation fan of a limestone wet desulphurization system, maintaining the combustion condition of the boiler, keeping the operation parameters of the desulphurization equipment basically unchanged, and performing testing; if the content of CaSO3.1 / 2H2O in the filtered solid of the tower collecting slurry is greater than 1%, ending the test; and calculating the natural oxidation rate of the absorption tower slurry in the test. The embodiment of the invention provides the method for testing the natural oxidation rate of the slurry of the absorption tower, which is simple to operate, high in accuracy and rapid in measurement.

The invention provides a high-speed train dynamic performance parameter design optimization method, which relates to the field of parameter design optimization based on high-speed train dynamics simulation analysis, which can effectively use the overall target neural network proxy model to replace the high-speed train dynamics simulation model , combining the design analysis of high-speed trains in the multidisciplinary field with multi-objective optimization algorithms, the analysis and optimization based on the approximate model of high-speed train dynamics simulation are carried out. The specific steps of the method are as follows: establish a high-speed train multi-rigid body dynamics simulation model, determine the important input and output design space involved, select a sampling strategy to obtain a suitable design space sample set for high-speed train dynamic performance analysis; use Bayesian regularization The method improves the generalization accuracy of the overall objective neural network, and constructs an overall objective neural network proxy model with error control within a certain range by adjusting the number of nodes in the hidden layer; using the improved overall objective neural network proxy model, combined with differential evolution intelligence The multi-objective optimization algorithm is used to obtain the optimized high-speed train design parameters. It is mainly used for dynamic analysis and design optimization of high-speed trains.

A simplified design calculation method for tunnel and underground space different cavity shape surrounding rock pressure comprises the following steps that according to known conditions provided by the design of the tunnel and the underground space, the length-width ratio n and the depth influence coefficient value n' of a sunken soil column are obtained, wherein n '= 2n / (1 + 2n); n and n' judge the shape of the cavern; according to the geological conditions and the grades of the surrounding rocks, physical parameters are determined: a cavity shape surrounding rock cohesive force c, an internal friction angle weight gamma, a Poisson's ratio mu and an initial side pressure coefficient xi which are equal to / (1-mu); and the surrounding rock pressure values of the tunnel and the underground space by applying a simplified formula corresponding to the shape of the corresponding cavity are calcualted. Surrounding rock pressure values calculated through the method are well matched with measured values, and the engineering actual situation is met. A beneficial reference value is provided for application of the load structure method to guidance of engineering practice.

The invention provides a rock mass test flexible oil cylinder, a loading system and a mounting method of the loading system. The rock mass test flexible oil cylinder comprises an inner steel frame, anouter steel frame and a pressure-bearing oil bag arranged between the inner steel frame and the outer steel frame, wherein the inner steel frame and the outer steel frame are connected through a boltbody, the bolt body is internally provided with a hollow oil hole communicated with an oil cavity, hydraulic oil in the oil cavity is injected and led out through the hollow oil hole of the bolt body, and the pressure-bearing oil bag is manufactured through one-time demolding. The rock mass test flexible oil cylinder is used for being arranged on the periphery of a rock mass sample in a surrounding mode to conduct a flexible loading test. The pressure-bearing oil bag in the flexible oil cylinder is manufactured through one-time demolding, the peripheral frame of the pressure-bearing oil bag and the oiled side surface are welded after being clamped by the inner steel frame and the outer steel frame, so that the side surface facing the rock mass is weldless, the pressure-bearing oil bag isnot prone to burst and oil leakage when expanding and pressurizing, the service life is long, and high safety and reliability are achieved.

The invention discloses a simulation method of oil and gas pipeline welding joint inner crack expanding based on fluid and solid magnetic multi-field coupling, and belongs to the technology of oil andgas pipeline welding joint inner crack detection. A leakage magnetism method is utilized to detect serviced pipeline welding joint inner cracks, and the pipeline welding joint inner crack expanding representing and evaluation problem under the effect of fluid and solid magnetic multi-field coupling is solved. The method is characterized by comprising the steps of building a fluid and solid magnetic multi-physics field model of pipeline welding joint inner crack expanding; constructing fluid and solid magnetic multi-field coupling; calculating pipeline welding joint inner crack expanding; conducting grid reconstruction for a computing domain around the pipeline welding joint inner cracks; conducing leakage magnetic field analysis in the progress of pipeline welding joint inner crack expanding; judging whether pipeline welding joints are cracked or not. By means of the fluid and solid magnetic multi-field coupling simulation method, the inner crack expanding degree can be represented, and the danger level of the damage of the pipeline welding joints is judged. By means of the implementation of the method, technical guarantee can be provided for the leakage magnetism method to detectand evaluate the hidden defects of the serviced pipeline welding joint inner cracks, conduct reproductive repairing or replace oil and gas pipelines.

The invention discloses a testing method of a single-pile multi-directional horizontal bearing force under combined loading effect. The method comprises the following steps: (1) determining the size of a test pile, soil distribution and thickness; (2) determining a vertical loading value and a loading level, and a horizontal loading value and a loading level; (3) paving soil in layers; (4) determining loading direction and quantity of horizontal loading; (5) mounting horizontal loading pile caps; (6) placing a horizontal loading system; (7) placing a vertical loading system; (8) mounting a data acquisition system; (9) determining multi-directional ultimate bearing capacity of the test pile for single time; (10) detaching the test device and recycling soil samples for testing; (11) determining horizontal bearing capacity characteristic values of a single pile under different vertical loading; (12) determining the horizontal ultimate bearing capacity of the single pile under different vertical loading; The method has a good effect, is convenient to operate and low in cost.