Monte Carlo simulation for seismic analysis of a long span suspension bridge

• We performed a probabilistic seismic analysis of a long span suspension bridge.
• We have modelled the seismic input asynchronously.
• The results of the analyses reported show a rather symmetrical result.
• Vertical displacements of the bridge deck are more influenced by the uncertainties.

The seismic analysis of long-span cable suspended bridges is undoubtedly a problem in structural analysis that involves a high number of uncertain parameters. In this work, through a probabilistic approach (Monte Carlo simulation) seismic analysis is carried out able to take into account the variability of certain factors relating to the seismic input. Displacement time histories, necessary to define seismic scenarios, are built artificially based on the response spectrum of the site. The analysis is carried out using a 3D numerical model built using one-dimensional finite elements using ADINA software code. This model has been developed in conjunction with a purpose-built program in FORTRAN language to conduct the Monte Carlo simulations. The results expressed in terms of displacements and stresses are described by their average value and their variance.