Las estructuras a tracción y sus materiales

Tension structures and their materials

The paper offers a general revision on tension structures, used for different purposes, emphasizing on two-dimensional ones. Tipologically, they are membranes (continuous structures) and cable or strand spatial nets (discrete structures); from a functional point of view, they are mainly roofs for covering small and medium surfaces, small capacity reservoirs, small height dams with regulable shape and floating or submerged elements. It begins wondering why this structures exist, doing an analysis of their different specific characteristics (material economy, ligthness, stiffness, continuity, flexibility of installation, shape adaptability, etc., besides of the necessary strength and durability), which make the suitable for such uses. Later, the work is focused to the materials to be employed in, insisting inicially on the topics more conditioning of their properties: functional, including a description of the different types of constructions involved, structural and even some of constructive ones having influence on them. Departing from this, a revision of materials conforming all this structures, with their specific requirements, is presented and also their particular properties. Finnaly, a prospective of their evolution from the current situation is pointed out, imagining the appeareance of new structures covering uses others than the well known ones till now.