The knowledge of the resistance, the vulnerability to earthquakes and the confidence level to collapse of existing railways bridges are now considered very interesting topics. In Italy a great number of iron railway bridges were constructed at the end of the nineteenth century. Although the traffic on this lines is limited in volume and in speed, these old structures require inspections and reliability analysis to understand their status and the type of restoration to be used. In this paper an ancient railway bridge in service on the Avellino-Rocchetta-Foggia line (in the South of Italy close to the Lapio village) is investigated. A reliable procedure based on experimental and theoretical analyses is proposed and applied. At first, the study of technical reports, the visual inspection and the material and dynamic tests are carried out. Then an identification procedure to pick the presence of structural non-linearities is proposed. Finally a finite element model of a bridge is optimised and then used to perform the modal analysis, to evaluate the magnification factor and to assess the vulnerability to seismic loads.
Some iron railway bridges of the 19th century built in Italy:recent experimental investigations and analytical modelling
FERRAIOLI, Massimiliano;MALANGONE, Pasquale;
2003
Abstract
The knowledge of the resistance, the vulnerability to earthquakes and the confidence level to collapse of existing railways bridges are now considered very interesting topics. In Italy a great number of iron railway bridges were constructed at the end of the nineteenth century. Although the traffic on this lines is limited in volume and in speed, these old structures require inspections and reliability analysis to understand their status and the type of restoration to be used. In this paper an ancient railway bridge in service on the Avellino-Rocchetta-Foggia line (in the South of Italy close to the Lapio village) is investigated. A reliable procedure based on experimental and theoretical analyses is proposed and applied. At first, the study of technical reports, the visual inspection and the material and dynamic tests are carried out. Then an identification procedure to pick the presence of structural non-linearities is proposed. Finally a finite element model of a bridge is optimised and then used to perform the modal analysis, to evaluate the magnification factor and to assess the vulnerability to seismic loads.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
