ABSTRACT
During the last years, several problems and pathologies derived from flaws in the prestressing grouting system have been detected in Spain, which has led to costly repairing operations, and even to the demolition of viaducts placed, in many cases, in main arterial communication lines.
As it is well known, these problems had already occurred in Europe and the US during the 80´s, the 90´s and the beginning of the 00´s. They have been detected in Spain recently, with the logic time-lag considering the different infrastructure level of development between the mentioned countries.
This paper provides an overview of the main problems that have been encountered, frequently associated with alkali-aggregate reaction, failure of drainage and water-proofing systems, and the usage of deicing salts, which, together with inadequate grout injection, have led to severe corrosion problems in prestressing cables.
Some relevant cases detected in Spain are shown. Detected pathologies are described, and management, technical and administrative decisions that were taken are analyzed.
Among the mentioned cases, different structures from the main ring road in Madrid, the highway M-40, are included. Additionally, several bridges placed in the highway A-6 (North-West of Spain), with different age and prestressing systems, are shown, including the viaducts of “El Castro”, a precast segmental structure with external prestressing.
