Abstract
During the scope of a research project a prestressed concrete structure, Sorraia River Bridge, is being continuously monitored with the purpose of performing it assessment. Concrete structures when exposed to hard environmental conditions, tend to deteriorate. Such deterioration is the principal cause for them to become anesthetic and unsafety. Is also responsible for rising the costs related with it maintenance. The developed continuous monitoring system intends to help owners to achieve a better structure maintenance by controling the long term structural behaviour and so reducing it degradation. In this paper a brief description of the bridge and of the instrumentation plan is realized. A methodology that intends to perform the structural assessment is also explained and some results presented.