Motorway overpasses

U radu se opisuju osnovni pristupi projektiranju i izvođenju nadvožnjaka kao najčešćih objekata na autocestama. Uz podloge za projektiranje prikazuju se i dispozicijska rješenja za različite karakteristike terena. Opisana su konstrukcijska rješenja, s isticanjem prednosti pojedinih konstruktivnih sustava, a također su prikazani i određeni pristupi tehnologiji građenja nadvožnjaka uz analizu osnovnih karakteristika pojedinih rješenja. Istaknut je i problem sigurnosti prometa.Principal approaches to the design and construction of overpasses, the most frequent motorway structures, are described in the paper. In addition to description of background data needed for the design, the author offers several overpass disposition alternatives corresponding to various properties of the terrain. Structural solutions are described and, at that, advantages of each individual structural system are given. Several approaches relating to the overpass construction technology are presented, with the analysis of basic properties of individual solutions. An emphasis is placed on the traffic safety problem