ABSTRACT
ABSTRACT The ASFiNAG road network contains more than 5000 bridges. Most of them are made of reinforced or prestressed concrete. In Austria strong winters are obligatory. Therefore de-icing measures are used for thawing. These substances contain chlorides, which dissolve in water. Several elements of the bridges – especially the columns – are strongly exposed to such a chloride-solution. Additionally, more than half of the structures were built in the 1970's or 1980's. They have been exposed for many years to this chemical attack and accurate assessment and prognosis of the concrete degradation is vital for the economic preservation of the concrete structures. The LA-ICP-MS (Laser Ablation Inductively Coupled Plasma Mass Spectrometry) method presented in this paper is a fast and reliable analysis method for determination of the chloride content in the cement paste of existing concrete structures. The high depth resolution, the accuracy and the distinction of the concrete phases delivers meaningful data for assessment and forecast. For this purpose Chloride-profiles were determined in short intervals (Weekly). Together with moisture monitoring at two concrete depth, environmental data and the records from the de-icing salt deposit important interrelations and dependencies can be revealed. The paper focuses on the interactions between environmental loads and the chloride profile extracted from an affected RC-Component. Finally, a model for prediction of the chloride profile using environmental and monitoring data will be evaluated regard to their input parameters.
