Pontes mistas de aço e concreto em seção caixão com protensão externa: procedimentos de cálculo e de projeto

This paper aims to present the design procedures and the guidelines for construction aspects of steel-concrete composite box girder bridges with external prestressing. The association between steel and concrete has been an efficient solution for the formation of composite structural elements, generating important advantages, such as dispensing formwork and shoring; reduction of own weight and volume of the structure; increased dimensional accuracy; reduction in consumption of structural steel and less need for protection against fire and corrosion in metal profiles. In turn, prestressed concrete is characterized by the introduction in the structure of stresses opposite to the loads resulting from its use, resulting in an improvement in strength and in its mechanical behavior. In this context, the steel-concrete composite structures with external prestressing are a great solution to overcome large spans, meet architectural limitations and to reinforce/recover existing metallic or composite structures. In view of this, and justified by the growing demand for construction techniques and the need to improve the country’s infrastructure, research into new technologies with the intention of using them is of great value.