Reliability Theory Analysis And Test On Proving Ground Correlated With Customers Usage Of Big Operation Vehicle

Fatigue damage of key components of big operation vehicle is one of the mainly reason of the commonplace traffic accident in recent years. Proving ground reliability test is an effective method to quickly and systematically evaluate fatigue characteristics of key components and reliability of vehicle. Therefore, it is significant to research on proving ground reliability test of big operation vehicle.The paper carried out the research work on prediction and analysis of key components’fatigue life and reliability, collection and analysis of load, establishment of the target customers usage load spectrum and correlation characteristic between proving ground reliability road and customers usage road for big operation vehicles.A correlation model between strength degradation and cumulative fatigue damage was established based on characteristics of strength degradation under metal fatigue and further verified that the strength degradation process met the irreversible thermodynamics condition. A new fatigue cumulative damage models based on the correlation between strength degradation and cumulative fatigue damage were established, and was verified by fatigue test under two-level and three-level loading. A time-dependence reliability and reliability sensitivity analysis model and a time-denpendence reliability design considered the effects of interaction under uncertainty of initial parameters and actual use based on stress and strength interference theory and deducing of an equation of one-dimensional Brownian movement considered uncertainty of initial parameters.The customers usage’s speed condition used the method of dynamic clustering was constructed by investigating customers usage’s information of a passenger transport enterprises and obtaining big operation vehicles’ GPS data. The collection of road load for a big operation vehicle under proving ground reliability road and customers usage road relied on the requirement of customers usage road’s and proving ground’s speed condition, and testing program for the big operation vehicle’s load collection.The correlation between maximum and RMS from wheel spindle nose of each directions’ accelerations under proving ground reliability road and customers usage road were studied by data processing, statistics and analysis. Load spectrum under proving ground each reliability roads were obtained by using rain flow counting and zero mean conversion, and its distribution characteristics and distribution coefficient of the big operation vehicle under customers usage road were regressed.The change characteristics between spectral density of road pavement with using year was regressed and derived based on regression of the relationship between riding quality coefficient with using year, combination with pavement riding quality index and international roughness index, and pavement density dependence index with power spectrum. A method considered the change between customers usage goal’s load spectrum with using year for big operation vehicles was proposed by establishing and verification of vehicle dynamics model and load of customers usage operating speed condition at different using age.A relative fatigue correlated model for proving ground reliability road and customers usage target road was proposed under the premise of a pseudo accumulative fatigue model’s construction from acceleration and Miner accumulative fatigue model’s correction from the Habich’s fatigue characteristics. Matching results of the spectra correlated model, the damage model and the relative damage correlated model were compared, and integrated acceleration factor, total testing distance and testing cycles in proving ground reliability road by using the damage correlated model and the relative damage correlated model were calculated.