| dc.description.abstract | The Norwegian railway network features numerous steel bridges that were constructed over
60 years ago. Progress in technology and an increasing population have resulted in different
and larger traffic conditions than the conditions when they were designed. It is therefore vital
to evaluate the fatigue damage of the railway bridges to determine which of them are at the
highest risk and need repairing or replacement to avoid possible collapse of the structures.
The aim of the study was to investigate how sensors and FEM-models can be used to
improve the assessment of fatigue damage on old railway steel bridges. A literature review
was conducted together with and experiment. In order to make an assessment of the most
critical components, a FEM-model was constructed based on an existing riveted Warren
truss bridge. To find the historical fatigue damage, a conservative and consistent load model
from NTNU was used in the calculations. The existing railway bridge was instrumented
with strain gauges and accelerometers to provide sensordata for the train passages. The
structural response from an NSB-73 train passage was compared between the FEM-model
and the strain gauges.
The results show that several elements of the structure exceed the critical damage value,
indicating that the components have no remaining fatigue life. The study demonstrates that
it is possible to improve fatigue analysis by combining FEM-models and sensor data. | |