Numerical Modeling of a Tensioned Diagonals Replacement at a Historic Puddled Iron Bridge

The historic Imperial Dom Pedro II Bridge, located in Bahia, Brazil, underwent a major rehabilitation program that began in 2018. All tensioned diagonals, made of puddled iron, were replaced with new components, made of stronger steel. This paper presents a numerical model of the Dom Pedro II Bridge capable of reproducing structural performance before and during the replacement work. Numerical results were verified by the experimental data derived from monitoring systems installed in the bridge on several occasions. The differences observed from the numerical results could be justified by the bridge’s age and maintenance condition. In general, the numerical results were fairly similar to the measured data, indicating the numerical solution could be used to assess other sequences of tensioned diagonal replacements. It was concluded that the replacement work improved the safety of the bridge, and the proposed modeling process may be suitable for other sequences of replacements, including other steel truss bridges.