The study endeavors to provide statistical inference for a (1 + 1) cascade system for exponential distribution under joint effect of stress-strength attenuation factors. Estimators of reliability function are obtained...The study endeavors to provide statistical inference for a (1 + 1) cascade system for exponential distribution under joint effect of stress-strength attenuation factors. Estimators of reliability function are obtained using Maximum Likelihood Estimator (MLE) and Uniformly Minimum Variance Unbiased Estimator (UMVUE) of the parameters. Asymptotic distribution of the parameters is also obtained. Comparison between estimators is made using data obtained through simulation experiment.展开更多
Existing studies on the durability of subsea tunnel mainly focus on the concrete deterioration and steel corrosion,while there are few on the infuence of mechanical properties deterioration of surrounding rock on the ...Existing studies on the durability of subsea tunnel mainly focus on the concrete deterioration and steel corrosion,while there are few on the infuence of mechanical properties deterioration of surrounding rock on the durability of sub-sea tunnel.To improve the accuracy of long-term stability prediction,seawater corrosion tests of intensely weathered surounding rock of subsea tunnel are car-ried out.In this study,the strength characteristics of remolded samples of inten-sely weathered granite under different seawater concentrations are investigated,the strength attenuation equation under seawater corrosion is established,and the chemical damage evolution equation and model parameters are formulated,The findings provides the basis for analyzing the influence of corosion and weak-ening of surrounding rock on the durability of tunnel within the operation period.展开更多
文摘The study endeavors to provide statistical inference for a (1 + 1) cascade system for exponential distribution under joint effect of stress-strength attenuation factors. Estimators of reliability function are obtained using Maximum Likelihood Estimator (MLE) and Uniformly Minimum Variance Unbiased Estimator (UMVUE) of the parameters. Asymptotic distribution of the parameters is also obtained. Comparison between estimators is made using data obtained through simulation experiment.
文摘Existing studies on the durability of subsea tunnel mainly focus on the concrete deterioration and steel corrosion,while there are few on the infuence of mechanical properties deterioration of surrounding rock on the durability of sub-sea tunnel.To improve the accuracy of long-term stability prediction,seawater corrosion tests of intensely weathered surounding rock of subsea tunnel are car-ried out.In this study,the strength characteristics of remolded samples of inten-sely weathered granite under different seawater concentrations are investigated,the strength attenuation equation under seawater corrosion is established,and the chemical damage evolution equation and model parameters are formulated,The findings provides the basis for analyzing the influence of corosion and weak-ening of surrounding rock on the durability of tunnel within the operation period.
