Conceptual Design of Bridges Structures: Some examples

In this paper current bridge design development is reviewed and different acting mechanisms in this process are identified. Some of the bridge design ingredients are discussed in the different paper sections. In the first section, the use of modern materials in bridge design is commented. Structural concrete, in its different versions, several forms of steel: bars, cable, beams and, finally, composite materials, i.e., the ones combining in their best use, concrete and steel. The second section is related with the extensive typology of bridges, i. e. compression structures (columns, arch, membranes, and shell systems), bending (beams, plates, cable stayed), combination of stresses (portal frame, vierendel, Maillart) and tension (suspension bridge or inverted arch) among others. In the following and in connection to the previous one bridge analysis is discussed. Next, the important topic of construction in the conceptual bridge design is studied, because frequently, during its construction the bridge suffers more severe loading conditions than during its service life and design details must be considered according to the construction procedure considered. Separate attention is paid to the specific methods of staging, push-out and cantilever. The next two sections are devoted to the currently Important items of new bridge functions, environment consideration, aesthetic and technical efficiency in bridge design (urban bridges) and bridge management in its aspects of extraordinary traffIC control, maintenance, early damage detection and repairing. Finally, in the framework of the above ideas some recent examples of bridge design are described.