摘要：This work describes the retro-analysis of design of rehabilitation of existing bridge over the river Cubiculo on BR-101 in Santa Catarina, Brazil, aiming to evaluate the intervention processes. In this way, it was verified that the project adopted for strengthening of the structure was not adequate to support the evolution of the maximum load over time and the overload due to widening, and it was also verified that the changes in the load factor do not comply with the update of the Brazilian Technical Standards ABNT： NBR-7188 [1]. The retro-analysis of the bridge rehabilitation project has demonstrated fundamental importance to avoid possible design failings, accidents, and reworks. Affirming that it is essential to comply with Standards and Technical Manuals on the elaboration of the rehabilitation project of structures and in choosing the type of intervention to the existing structure.