GB431484A - Improvements in methods and apparatus for the manufacture of moulded bodies from mortars or concretes - Google Patents

Abstract

431,484. Piles. FREYSINNET, E., 28. Rue St. James, Neuilly-sur-Seine, France. Feb. 9, 1934, Nos. 4372 and 4373. Convention date, Feb. 9, 1933 and Jan. 22, 1934. [Class 68 (ii)] [See also Group V] Piles are moulded from damp concrete by filling a non-rotary mould with the concrete which is then subjected, in a first phase, to vibration accompanied by pressure applied to the upper portion of the concrete, which pressure coacts with the vibration to produce compactness but is not strong enough to prevent relative displacement of the elements of the concrete, after which the compact concrete is subjected, in a second phase to a substantially greater compression, preferably obtained by reducing the size of the mould. Piles may be manufactured in successive portions as shown in Fig. 16. The mould 82 is connected by an element 81 to a previously formed portion of the pile and an expansible mandrel, comprising a wooden core 51 surrounded by an elastic envelope 53 and wooden staves 55, is placed inside, the mandrel having an annular projection 84 at the top end to form a recess in the concrete. Reinforcements 85 are placed in the mould which is filled by means of a hopper 86, the material in which provides the light pressure. The mould is vibrated by rotating eccentric masses. The hopper is then removed, a closure plate 87 is applied, and the mandrel is expanded by fluid pressure. When the mould is removed the end element 81<a> is left in position. The method is particularly applicable to screwed piles.