11 results about "Reliability theory" patented technology

This invention discloses a random field probability prediction method for long-term settlement of shield tunnels in heterogeneous strata, belonging to the field of underground engineering structural health monitoring and risk assessment. The method first inverts the micromechanical parameters of the strata through shield tunneling parameters, then constructs a three-dimensional anisotropic random field model, generates random field samples through K-L series expansion, and calculates the settlement field using a three-dimensional fluid-structure interaction finite element model and Monte Carlo simulation. Statistical analysis is used to predict the settlement probability, and finally, the probability of settlement exceeding limits is calculated based on reliability theory to complete the risk assessment. This invention breaks through the homogenization assumption, quantifies settlement risk, adapts to complex heterogeneous strata, provides a scientific decision-making basis for the whole life cycle management of tunnels, and has strong engineering applicability.

The invention discloses a control rod falling reliability analysis method based on random point collocation perturbation, and belongs to the field of reliability analysis. The method comprises the following steps: firstly, based on a control rod falling structure, constructing an uncertainty rod falling dynamic model, and determining random variables, random variable vectors and distribution thereof in a rod falling process; secondly, under the condition of considering a random variable, calculating a statistical characteristic value of rod falling time by adopting a random point collocation perturbation method based on an uncertainty rod falling dynamic model; thirdly, obtaining a probability density function of rod falling time based on a maximum entropy principle through statistical feature values; and finally, based on a reliability theory, calculating a control rod falling time reliability index. Reliability analysis is carried out based on the probability density function of the control rod falling time obtained through solving, and the calculation efficiency can be remarkably improved; the blank of control rod falling reliability analysis and research when random variables exist is filled; compared with a reliability analysis method, the efficiency of calculating the reliability index is higher.

The invention discloses a component residual bearing capacity evaluation method based on an entropy fuzzy analysis method, and belongs to the field of structural engineering. Existing evaluation methods such as subjectivity of an expert experience method and high cost of a load test method, a reliability theory depends on mass data, and weight of an existing fuzzy evaluation method is too subjective. The method comprises the following steps: simulating different damage rates of a component through a physical test, and establishing a dynamic critical value adjustment formula set; correcting the normalized matrix of the traditional entropy method to obtain dynamic entropy weight sets at different rates; collecting actual measurement damage data to construct a current and pre-judgment fuzzy judgment matrix, and combining the current and pre-judgment fuzzy judgment matrix into a compensation matrix; and a target layer fuzzy evaluation matrix is calculated in combination with the compensation matrix and the dynamic weight, a final reduction coefficient is obtained through correction, and then the residual bearing capacity is calculated. The problem of dynamic weight distribution under multi-damage coupling is solved, subjective dependence is reduced, damage rate changes are adapted, evaluation precision is improved, and the method can be used for structure maintenance decision making and emergency study and judgment after disasters.

The invention discloses an intelligent regulation and control method and system for water transportation, distribution and back supplement in a mining area. The method comprises the steps that pipe network operation data of a transportation and distribution pipe network and current multi-source geological and hydrological data are obtained; determining an optimal state estimation value of the pipe network by using a real-time hydraulic model and an ensemble Kalman filtering algorithm, and calculating a pressure residual error of each monitoring node; when the residual represents an abnormal working condition, determining a leakage result by using a leakage positioning algorithm; generating an emergency regulation and control decision by using an optimization scheduler based on the leakage result; when the residual represents a normal working condition, a scheduler is used for executing multi-time-scale predictive control through a real-time hydraulic model based on pipe network operation data to generate a transmission and distribution scheduling decision, and the pipe network is regulated and controlled to realize back-replenishing water transmission and distribution; performing multi-physics field coupling real-time simulation on the whole diffusion and migration process of the back-replenishing water by using the geologic structure digital twinborn model to obtain a back-replenishing prediction result; and evaluating the risk of the candidate supplementation scheme based on a reliability theory, and solving by using a multi-objective optimization algorithm to obtain a target supplementation scheme.

The invention provides a method for predicting and evaluating the service life of a reinforced concrete structure considering sulfate corrosion. The method is suitable for a concrete structure in a chlorine salt-sulfate composite medium corrosion environment. According to the method, a coupling model for diffusion of chloride ions and sulfate ions is constructed, diffusion parameters are corrected to consider interaction of the two ions, and the failure probability of steel bar corrosion and protective layer cracking is evaluated in combination with a reliability theory, so that the service life of a concrete structure is predicted. The coupling effect of chloride ion diffusion and sulfate ion diffusion is creatively integrated, the accuracy of the model is verified through experiments, a systematic life prediction method is provided, and a scientific basis can be provided for long-term performance evaluation and maintenance of infrastructures such as bridges and ports.

A reliability analysis method for control rod drop based on random collocation perturbation is disclosed, belonging to the field of reliability analysis. First, based on the control rod drop structure, an uncertain drop dynamics model is constructed, and the random variables, random variable vectors, and their distributions during the drop process are determined. Second, considering the random variables, the statistical characteristic values ​​of the drop time are calculated using the random collocation perturbation method based on the uncertain drop dynamics model. Third, using the statistical characteristic values, the probability density function of the drop time is obtained based on the maximum entropy principle. Finally, based on reliability theory, the reliability index of the control rod drop time is calculated. This invention performs reliability analysis based on the calculated probability density function of the control rod drop time, which significantly improves computational efficiency; it fills the gap in the research on reliability analysis of control rod drop when random variables are present; and compared with other reliability analysis methods, it is more efficient in calculating reliability indices.

This invention relates to the field of reliability engineering technology, specifically to a method and system for allocating certainty reliability indicators for an electrically driven turnout tamping machine based on a material-energy-information network. The method first performs functional decomposition and performance analysis of the entire machine, extracting key performance parameters of each subsystem and constructing performance margins. Based on certainty reliability theory, it determines the material-related reliability. Secondly, it establishes energy and information networks through the electric traction power supply relationship and the telemetry and control link, respectively, calculating the energy-related reliability and information-related reliability of each subsystem, and combining these three to obtain the subsystem functional reliability. Based on this, the system reliability is expressed as the minimum value of the subsystem functional reliability. System reliability interval constraints and performance margin mean and variance constraints are introduced to construct an optimization model with causal importance-weighted subsystem functional reliability as the objective function. An intelligent optimization algorithm is used to solve for the reliability indicators and margin allocation of each subsystem. This method can achieve refined and quantitative allocation of reliability indicators for each subsystem of an electrically driven turnout tamping machine under small sample and uncertain conditions, improving the reliability and safety of the entire machine under complex operating conditions.

This invention relates to the field of ship design technology and discloses a rudder system optimization design method based on nonprobabilistic reliability theory, comprising the following steps: S1: Determine the mechanical performance design values ​​of key components of the rudder system based on nonprobabilistic reliability indices, conduct parameter sensitivity analysis to determine the sensitive variables affecting the rudder stock torque, construct a parameterized model library, and generate a sample space through automated simulation scripts; S2: Call the parameterized model library to generate a three-dimensional model, perform finite element calculations of the rudder-propeller combination, simulate the hydrodynamic performance of the rudder system under different rudder angle conditions, and compare and analyze the results with reference data and standard calculations. By integrating nonprobabilistic reliability theory and comparing nonprobabilistic reliability indices and convex set models, parameter uncertainties are effectively handled, the reliability of the rudder system design is improved, and the optimization ideas of portal frame structures are used to reduce design constraints and improve efficiency.

The present application relates to the field of railway operation and maintenance technology, in particular to a simply supported beam bridge section TQI prediction method based on Gaussian random process, which comprises the following steps: step one, data collection and preprocessing of simply supported beam bridge; step two, construction of composite kernel function model suitable for bridge characteristics; step three, adaptive training and optimization of model parameters; step four, probability prediction and uncertainty quantification; step five, calculation of over-limit probability based on reliability theory; step six, residual life prediction and maintenance window generation; the present application can preferably predict the TQI of simply supported beam bridge section.

The invention provides a thin-layer weakly-cemented expansive rock tunnel safety risk grading method and a supporting structure, and relates to the technical field of tunnel surrounding rock engineering. Carrying out stratification feature recognition and index quantification on the expansive rock geological parameters, and constructing an index comprehensive judgment model; inputting the index comprehensive judgment model into a fuzzy neural network algorithm for coupling processing, and establishing a nonlinear risk evaluation model; according to a reliability theory and Monte Carlo simulation, determining a quantitative relation between a risk index and a surrounding rock instability probability in the nonlinear risk evaluation model, and constructing a dynamic risk threshold value; and performing grade division on tunnel construction risks based on the dynamic risk threshold, and performing dynamic feedback and parameter updating on a preset risk evaluation model in combination with real-time monitoring data to obtain a tunnel safety risk grading scheme. According to the invention, the prominent problem of unbalanced engineering safety risk and cost control is solved.

This application provides a reliability-based durability analysis method and apparatus for subsea immersed tunnels. The method includes: acquiring marine environmental parameters and tunnel damage parameters of the target subsea immersed tunnel; the marine environmental parameters include seawater chloride concentration, and the tunnel damage parameters include crack length, crack width, number of cracks, and crack initiation time; establishing a target steel reinforcement surface chloride concentration calculation model for the target subsea immersed tunnel based on a pre-defined calculation model related to seawater chloride concentration, crack length, crack width, number of cracks, and crack initiation time; and calculating the durability failure probability and reliability index of the target subsea immersed tunnel based on reliability theory and the target steel reinforcement surface chloride concentration calculation model. This application can obtain comprehensive and accurate durability analysis results for subsea immersed tunnels.