by making use of pressure liquid or pressure gas for compacting the concrete

Full Title

Bulkheads, piles, or other structural elements specially adapted to foundation engineering (engineering elements in general F16) > Piles (sheet piles, E02D5/02; ) > Concrete or concrete-like piles cast in position > making by use of mould-pipes or other moulds > by making use of pressure liquid or pressure gas for compacting the concrete