[S]tresses in one direction produce not only a deformation along this direction but also transversally, the relation of both being expressed by the s… - Eduardo Torroja

Before a man can successfully plan a structure... he must study, from every possible angle, the ultimate purpose of his building. Attention must be directed to the basic structural concept before the mathematical process of calculation is undertaken.

If you lean on a straight stick... [it] can resist your weight, despite its slenderness, as long as it remains straight; once it starts to bend, it will easily break. The danger of breaking increases with the deflection... [T]he danger of failure will diminish with the increased of the cross section, or if the same are of cross section should be maintained, by distributing the material in a hollow section.

Concrete presents, besides a coefficient of , a coefficient of hygroscopic dilation which is more appreciable. While concrete is kept wet... it expands; and as it dries, it contracts, in inverse proportion to the hygroscopic degree of the ambient air. ...The shrinkage ...will vary with the porosity of the concrete and with the thickness used in the structural member. ...Shrinkage is much greater in structures consisting of thin elements subjected to intemperateness of dry climate, and disappears or becomes negligible in underground structures (e.g., foundations).