| 摘要 |
<p>The hollow cylindrical concrete pile body is relatively thin-walled. Two concentric pipes (1, 2) on an annular footplate (7) with distance pieces (8) between them are driven into the ground by means of an impact cap (5) gripping them at the top. Concrete is then poured in between the pipes via a chamber formed at the upper end of the inner pipe above a barrier over the central hole (12) and through openings (14) in the inner pipe. At the same time the pipes, held together by the cap, are extracted, and the concrete flows into the annular space formed.</p> |
