Probabilistic Estimation of Airtightness Performance of Concrete Vacuum Tube Structures

A probabilistic analysis is performed where the pressure change inside a concrete tube is probabilistically estimated considering the uncertainties inherent in the material, system discontinuity and outside pressure. A set of uncertain variables that are related to the equivalent system air permeability and the atmospheric pressure are defined as random variables with specific distributions. The pressure change inside a concrete tube is then probabilistically described using both analytical and simulation approaches. The analysis confirms the need of probabilistic approach for evaluation of the airtightness performance of vacuum tube structures.