Strengthening of Older Prestressed Concrete Bridges with Cracks at the Stages of Construction

摘要

Older prestressed concrete bridges have often unforeseen cracks1 that cross lon9itudinal internal prestressing tendons. In the area of the cracks problems with corrosion and fatigue of the reinforcing steel and prestressing steel can develop. Especially the stages of construction are for coupled post-tensioned systems effected by these problems. The following paper deals with the strengthening of these bridges by additional external tendons. Principles of design and detailing possibilities are illustrated.