Questões de Língua Inglesa do ano 2007

           Rankine notes that adhesion is useful in helping ground stand up in temporary work but plays no part in his design, which is consistent with Coulomb s law. Adhesive or cemented strength may arise as small creep strains occur and as bonds develop in undisturbed sedimentary soils, but any such bonds are, in Rankine s view, destroyed by weathering, and in Coulomb s view destroyed by remoulding. These two founders of soil mechanics are in agreement.

Adaptado de: Andrew N.Schofield Disponível em: http://www2.eng.cam.ac.uk/~ans/habibx.html Acessado em: 13/04/2007.

In Rakine s view, bonds are destroyed

In contrast, Coulomb s method

According to the text, it is correct to say that Rankine method is

Choose the right alternative to complete respectively the blanks in the paragraph.

Since the Theory assumes that there is no soil wall friction, the force (Pa) is ____________ to the backfill surface. On the other hand, since the Theory takes the soil wall friction into consideration, the force (Pa) acts at an angle of from the to the wall. This results in both a vertical and horizontal component of the force (Pa).

Consider these statements about Rankine Theory.

I. It assumes that the wall is frictionless and the soil is cohesionless, the force is parallel to the backfill surface.

II. It assumes that the ground and failure surfaces are straight planes.

III. It assumes that the friction between soil and wall is of no consequence.

Which of them is correct?