Full probabilistic design of a submerged floating tunnel and format for partial safety factors

Authors

  • Franka E.M. Swaalf Delft University of Technology, Faculty of Civil Engineering and Geosciences, Stevinweg 1, 2628 CN Delft, The Netherlands; The Netherlands Organization for Applied Scientific Research TNO, P.O. Box 155, 2600 AD Delft, The Netherlands
  • Raphaël D. J. M. Steenbergen The Netherlands Organization for Applied Scientific Research TNO, P.O. Box 155, 2600 AD Delft, The Netherlands; Gent University, Department of Structural Engineering, Technologiepark-Zwijnaarde 60, 9052 Gent, Belgium

DOI:

https://doi.org/10.14311/APP.2022.36.0198

Keywords:

Eurocode EN1990, first-order reliability method, submerged floating tunnel, Monte Carlo simulation, partial safety factors, tether-stabilized, tether slackening, tether yielding

Abstract

A submerged floating tunnel (SFT) can be a promising solution for crossing a deep or wide waterway. This innovative concept however lacks research into its probabilistic design. In this research, the reliability of the tether-stabilized SFT is assessed. A first-order reliability method (FORM) and a Monte Carlo simulation (MCS) are performed for the limit state functions of the most important failure mechanisms. Stochastic variables are chosen so that a target reliability index of 3.8 for a reference period of 50 years is met. The calculated factors from the full probabilistic design are compared with the general recommended partial factors for strength and resistance from Eurocode EN1990. For the strength mechanisms, the calculated factors are smaller than the factors from Eurocode. However, for the equilibrium mechanism, the calculated factor for the unfavorable loading is larger than the factor from Eurocode and should be increased by 10% in order to design a safe enough SFT.

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Published

2022-08-18