ABSTRACT
In order to determine the behavior deterioration of tensile structures due to stress relaxation, symptom-based reliability analysis method with stress variations in the members as main symptom was established, while structural cable’s relaxation process over time was simulated by the relaxation formula of steel strand previously obtained from experiments. With the continuously changing of prestress values in the members, the amounts of stress change in the controlling member over time were employed for fitting of Weibull model curve, and the fitted Weibull curve was utilized for symptom-based reliability analysis and remaining lifetime prediction of cable dome structures. The results of reliability analysis had been corrected according to the differences between symptom analytical values and measured values which were here replaced by calculation values from relaxation formula of steel strand. The results from a case study show that remaining useful lifetime is gradually decreasing with the used years, and, the structural symptom reliability is decreasing with increasing values of symptom under the consideration of structural deterioration solely due to stress relaxation. The variation of the structural symptom reliability over the symptom values is featured with the characteristics of slowly decline in nonlinearity at early time and sharply decline basically in linearity at the later time.
