| 摘要 |
1,242,959. Piles; jetting apparatus. TOT AANNEMING VAN WERKEN N.V. 15 Dec., 1969 [20 Dec., 1968; 15 July, 1969], No. 60980/69. Headings E1F and E1H. A mould tube 1 for a concrete pile that is to be cast in situ is furnished with a looselyfitting shoe 2 and a plurality of pipes 3 extending longitudinally thereof and fixed to its outer surface, each pipe having a nozzle 6 with an oblique outlet-channel 7. While the tube is being driven by vibration a pressurized fluid e.g. water, is fed through the pipes to loosen earth beneath the shoe. When necessary e.g. while the shoe is in soft ground or during the initial driving stage, the supply of fluid is cut off, particles of earth being prevented from entering each pipe by either a non-return valve 8 or a porous sleeve, Fig. 3 (not shown). The tube 1 is subsequently removed. The invention is said to be applicable to a prefabricated pile. |
