Exercise 3. Read and translate text A. An arcuated structure, the one built up of arches, acts structurally on a flat plane, but if the arch is imagined pushed through space

Text A. VAULTS (part I)

An arcuated structure, the one built up of arches, acts structurally on a flat plane, but if the arch is imagined pushed through space, the form that results is a vault. In the case of a semicircular arch, the resulting vault is called a tunnel or barrel vault.

Usually such vaults are placed up on walls, but since the solid barrel vault is heavy, this causes the walls to spread out at the top. These lateral forces can be resisted by substantial buttresses along the walls or by thickening the wall. An example of a barrel vault raised to great height is the nave of Saint-Sernin, Toulouse, France, begun 1080. But, as Saint-Sernin also shows, solid barrel vaults result in dark interiors. A solution devised earlier by the Romans was to run additional barrel vaults at right angles to the main vault so that they intersected, resulting in a groin vault, opened up by wide semicircular lunettes at each end and along the sides. With this arrangement, the forces are channeled down along the groins where the vaults intersect and are concentrated at points at the foot of the vaults.

An arch rotated in three dimensions about its center generates a dome; a semi­circular arch thus makes a hemispherical dome. The dome is a massive shell of concrete, 4 feet (1.2 meters) thick at the top, where there is the broad, single opening of the eye, or oculus, 30 feet (9.1 meters) across. The wall of the drum below, also 21 feet (6.4 meters) thick and supporting the five thousand tons of the dome, is hollowed out by niches 14 feet (4.3 meters) deep, so that in fact it func­tions structurally as sixteen radial but­tresses, connected at their tops by radial barrel vaults.

The weight of the concrete per cubic foot in the Pantheon was varied by the Roman architects and engineers by means of the materials used to make up the concrete. Concrete is a thick viscous material mixed of water, an aggregate of broken rock (caementa in Latin), and a binding material derived from lime that will cement every­thing together. In the concrete of the Pan­theon, the rock aggregate was varied from the very densest and heaviest basalt in the foundation ring, where the greatest weight had to be carried, to pumice in the part of the dome nearest the oculus, in an effort to reduce the loads from above.

Exercise 4. Translate the words:

vault, buttress, lunette, shell, dome, aggregate, basalt, oculus, lime, nave, cement, devise, effort.

Exercise 5. Choose the right translation from A to B:

A: vault, dome, shell, cement, intersect, arrangement, solution, point, generate, buttress.

B: купол, цемент, пересекать, решение, расположение, образовывать, точка, опора, свод, каркас.

Exercise 6. Are these meanings correct or incorrect? Correct the mistakes:

aggregate – агрегат

devise – устройство

lime – глина

vary – изменяться

foundation – фундамент

build up – размещать

cause – приводить к ч-л.

connect – распределять

bind – строить

Exercise 7. Translate the following word combinations:

tunnel vault, semicircular arch, result in, groin vault, foot of the vaults, massive shell, wall of the drum, viscous material, aggregate of broken rock, binding material.