Foundation Reliability of Anchor Block for Suspension Bridge

Abstract

The suspension bridge across the eastern channel of Great Belt with a main span of 1624 m is part of the Great Belt Link in Denmark scheduled to be finished in 1997. A reliability study of foundation failure for the western anchor block has been performed in order to obtain quantified assessments of the reliability. The two different anchor block structures submitted for tender — Caisson and In-situ cast anchor blocks — have been investigated. The present paper describes the investigations carried out for the in-situ cast anchor block.

Sliding failure and zone failure mechanisms are considered. The work has included development of stochastic load models and a stochastic field model of soil strength parameters, including field tests by Kriging and the possibility of taking consolidation effects into account.

Limit state formulations based on work principles have been developed for the failure mechanisms. The integral expressions for energy dissipation in the soil were calculated by simulation techniques. Failure probabilities were calculated for the optimum failure mechanisms determined by traditional deterministic upper bound techniques.