Steffen Marx, Gregor Schacht 3rd fib International Congress - 2010 1 CONCRETE HINGES – HISTORICAL DEVELOPMENT AND CONTEMPORARY USE Steffen Marx, Prof. Dr.-Ing., Inst. of Concrete Structures, Techn. Univ. Dresden, Germany Gregor Schacht, Dipl.-Ing., Inst. of Concrete Structures, Techn. Univ. Dresden, Germany ABSTRACT Articulated connections consisting of concrete have existed since 1880, when Claus Köpcke first used saddle bearings in a natural stone-arched bridge. Further developments were made in France at the beginning of the 20 th century. While Mesnager used reinforcement to carry the loads of his Mesnager hinges, Freyssinet developed an unreinforced hinge that transmits loads only through the concrete. All hinges work on the same principle – the centering of compression stresses in a very small zone (the throat of the hinge). Concrete hinges have also been used in Germany, in the USA and, particularly, in Switzerland. In the 1960’s, the work of Fritz Leonhardt (Germany), E.O. Fessler (Switzerland) and G.D. Base (Great-Britain), which define the international state-of-the-art until today, led to a renaissance of concrete hinges. The existing design rules are half-empirical and disallow the proper construction of concrete hinges up to the state-of-the-art. Investigations of the existing experiences and design rules were carried out. The design rules given by Leonhardt have been assigned to allow an appropriate design of unreinforced Freyssinet hinges which conform to current code. Keywords: concrete hinge, Freyssinet hinge, tri-axial compression stress state, Mesnager hinge, saddle bearing,