Title: Time-Invariant and Time-Variant Reliability Analyses of Reinforced Concrete Systems with Appraisal Data Missingness (with Appendix)
Author(s): Vincent Z. Wang and Nagaratnam Sivakugan
Publication: Structural Journal
Appears on pages(s): 1167-1178
Keywords: appraisal; expectation-maximization (EM) algorithm; missing data; reinforced concrete; statistical inference; time-invariant reliability; time-variant reliability
This paper deals with reliability analyses of in-service reinforced concrete (RC) systems with the missingness of some structural appraisal data. After succinctly illustrating the appraisal data missingness, both the time-invariant and time-variant reliability analyses are performed based on the expectation-maximization (EM) algorithm with access to only incomplete structural appraisal data. Specifically, the time-invariant analyses allow for the combination of dead and live load effects, as well as their magnitudes; while in the time-variant analyses, hazardous loading with different values of the occurrence rate and the degradation of the resistance of an RC system with time are considered. The performance function of an RC system is configured such that it may appositely take into account the existent safety redundancy in the system. With a nonparametric statistical inference technique, simulated and field-collected structural appraisal data are then used to demonstrate the effectiveness of the formulated framework for the reliability analyses.