Eduardo Torroja Quotes

[S]tresses in one direction produce not only a deformation along this direction but also transversally, the relation of both being expressed by the so-called Poisson ratio. However, the consideration... is of no great importance for the first, approximate judgement.

[El Instituto Técnico de la Construcción y del Cemento] had shown that it is possible in Spain to create organizations in which there exists a perfect harmony between different professions, between those above and those below; organizations in which everyone is able to live a life of high human rank, as gentlemen, a life of mutual respect and help and of maximum personal dignity.

One should become so familiar with the structure as to have the feeling of being, in full vitality and sentiment, part of it and of all its elements. ...it is necessary to achieve a sincere Einfühlung [empathy] of the process of resistence... through the deformation that is always essentially united with the process of stressing. ...[T]he comprehension of a structure requires intuitive knowledge of the ethology of its resistance and of its constituent materials.

Even children know that drafting rule is easier to bend flat than across the edges; and... they will not be much surprised if told that for the same width of the rule its resistance is proportional to the square of the thickness and the deflection is inversely proportional to the cube of the thickness. Nevertheless some modern designers seem to be unaware... since they require... beams of such slenderness that they resemble springboards...

Mathematics is merely a convenient tool by which the designer determines the physical proportions and details of a planned structure in order to transform his ideas... to the actuality of a finished structure.

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).

Bricks are considered to be the first material created by human intelligence from the four elements: earth, air, water, and fire. ...The great variety of designs and effects that artists of the past, especially the Arabs... were able to create in their brickwork, assembled with an element so monotonous... can be compared only with the beauty and attractiveness a romantic poet attained by adjusting his verses to the rigidity of a formal meter.

[E]xperimental investigation of stresses in a plane structure is of great interest and merit as applied to shells with single curvature (barrel shells, pipes) and to shells with double curvature (domes, etc.). In these structures similar states of stress are produced and can be determined at any point as acting in a plane tangential to the center layer of the shell.

Structural design is... very much concerned with art, common sense, sentiment, aptitude, and enjoyment of the task of creating opportune outlines to which scientific calculations will add finishing touches, substantiating that the structure is sound and strong...

The material in all elementary parts of a structure must have the properties of resistence to all internal forces produced by general loading conditions and by the action of any exterior force.

Stress phenomena are... not independent of scale, as was the case pertaining to simple external static equilibrium. ...with increasing dimensions of a structural element the volume and therefore the proper weight increases more rapidly than its cross-sectional areas...

The technical literature on structural engineering abounds with theoretical works of a mathematical nature, but few publications are concerned with the various kinds of structures or the fundamental reasons for their existence.

The equilibrium... in order to become static—should be steady, permanent, lasting. ...This type of equilibrium... is... independent of any scale. A reduced model will show the same effects as the proper structure. Experiments on models are simple and... instrumental for understanding such structural problems.

In general, these phenomena are very easy to perceive and understand, but difficult to calculate. The danger of failure increases rapidly with decreasing depth or thickness of the structural member...

[M]ost of our structures in the past consisted of individual members having relatively small transverse dimensions as compared with their length, and in such members stress analysis is much more simple. ...[M]any modern structures consist of frameworks of this type, and frequently the word "structure" refers specifically to assemblies consisting of linear elements.