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A new concrete arch bridge with 204.0 m span was constructed across the Krka River canyon on the section Skradin-Šibenik of the Adriatic highway. The bridge site lies in an environmentally protected area very close to the Krka national park. The superstructure is continuous with spans L=3x32.0+3x28.0+3x32.0+28.0+24.0=360.0 m. The application of the composite superstructure, made possible significant reduction of the dead weight and enhanced the bridge appearance in comparison to other Croatian concrete arch bridges. The construction of the bridge across the Krka River canyon commenced in the year 2003 and was successfully completed in two years in the year 2005. The whole arch cross section was constructed by free cantilevering, on traveling formwork carriages, in segments 5.25 meters long, starting symmetrically from arch abutments. Double columns at the arch abutments had to be extended by auxiliary steel staying pylons to facilitate successive cantilevering. The arch was supported during construction by stays equilibrated by anchor stays, connected to rock anchors. The steel superstructure grillage was erected by longitudinal launching in three phases. The concrete deck plate constists of from full depth precast slabs interconnected by on site concreting of longitudinal and transversal joints above shear connectors. A detailed review of the Krka Bridge construction is elaborated upon in the paper.

Principles of structural art in bridge design are explained in this paper. Significant Croatian arch bridges from Roman times to contemporary structures are described. Their constructional, functional, economical and aesthetic features – their characteristic raising them to the level of art are contemplated. Designers of these bridges, brought into designs their great engineering knowledge on safety, serviceability and durability but also their own creativity, originality, sensibility, and intuitive judgement.

The calculation procedure of longitudinal movements for selection of expansion joints is presented in the paper. Proposals for thermal actions, the correction factor for movements due to creep and shrinkage and equations for design movements are given.