GB650083A - Improvements relating to methods of casting concrete piles and apparatus therefor - Google Patents

Abstract

650,083. Concrete piles. ARMAND, L. July 15, 1948, No. 19072. Convention date, July 18, 1947. Class 68 (ii)] Concrete piles are cast in situ by compacting concrete around the head of a false pile, driving the false pile with the concrete plug into the ground whilst pouring concrete into the cavity so formed, and when the desired depth is reached, applying vibration to the head of the false pile to reliquefy the concrete and then withdrawing the false pile whilst continuing the vibration. As shown in Fig. 4, the false pile consists in an I-section joist 1 with its upper end 2 reinforced and carrying a point 4 at its lower end. Immediately above the point is mounted a ring 3 of shape corresponding to the cross sectional shape of the pile to be formed and which surrounds a combined ram and vibrator 5 operated by compressed air. In operation, the false pile is supported with its head in funnel 9 containing wet concrete. The vibrator is started, causing concrete to compact into a plug or seal under the ram 5 and within the ring 3. Driving is commenced, concrete flowing into the hole around the joist 1. On reaching firm ground, the vibrator is restarted and the concrete around the head reliquefies and flows through space 31 allowing the false pile to be withdrawn. Locally thickened parts 15 and 16 (Fig. 10) of the in situ pile are produced by stopping the vibrator and resuming driving, the concrete compacting under the ram and forcing the concrete below it outwardly. Metal reinforcement can be embedded in the pile as shown.