Bridges have evolved over time from the simplest forms made from materials found in nature – wood and stone - to the complex shapes of today, made of concrete, steel, steel-concrete, and composite materials. If in the past the large dimensions of an obstacle impeded building a bridge, today this problem can be solved by choosing suitable materials, an advantageous structural system, and an erection method that favors the chosen solutions.
The composite superstructures made of steel-concrete have started to be used more often in the construction of bridges due to their advantages. The scope of this paper is to analyze the evolution of road bridges with steel-concrete composite superstructure. There can be distinguished mainly 4 stages in the evolution of these types of structures. In the first two stages during 1850-1925 the connection between concrete and steel was achieved by the adhesion between the contact surfaces of the two materials. Starting with 1932 (stage III), a connection was realized that takes over the forces of friction that develop at the contact between the two materials. These connecting elements took different forms: loops the reinforcement, U, L, or ⊥ metal parts, shear stud connectors, and more recently composite dowels. The advantages of different types of connectors have been highlighted by various calculation methods, practical applications, and high productivity.
Nowadays the construction of an impressive bridge has become a source of pride at an international level, a way to demonstrate the technological progress in the field. But what

composite, superstructures, evolution, future