Geotechnical Problems in a Bridge over Corinth Canal

The railroad bridge of Corinth Canal was founded in a stable tectonic block (horst) consisting of neogene marly limestones, marls and sands. After the last strong earthquake of 24th February 1981 an extension of existed subvertical joints, directed E-W, was observed close to the northern bridge abutment. A geotechnical study was carried out for the detection of the causes which created these phenomena and for the design of probable reinforcing measures. From the results of site investigations and laboratory tests and after considering the slope stability, it was concluded that the only risk for the abutment is the progressive change of joints apperture and their erosion due to rain water. To minimize this risk, the installation of inclined untensioned grouted dowels was proposed and the continuous monitor of joints apperture especially during future strong earthquakes