Abstract: The invention relates to a staircase element comprising a tubular mast erectable to a vertical position onto the floor or a corresponding surface of a stair hall, and fillable with concrete; stair step elements fastened at their first end stepwise to the mast and branching off radially from the mast; at least one tubular stringer fastened to the second end of the stair step elements, fillable with concrete and connectable with fastening members to at least one wall of the stair hall, for supporting the stair step elements at their second end and for anchoring the staircase element to a building. The invention also relates to a method for building a staircase.

Abstract: The invention relates to a staircase element comprising a tubular mast erectable to a vertical position onto the floor or a corresponding surface of a stair hall, and fillable with concrete; stair step elements fastened at their first end stepwise to the mast and branching off radially from the mast; at least one tubular stringer fastened to the second end of the stair step elements, fillable with concrete and connectable with fastening members to at least one wall of the stair hall, for supporting the stair step elements at their second end and for anchoring the staircase element to a building. The invention also relates to a method for building a staircase.

Abstract: The invention relates to a staircase element comprising a tubular mast erectable to a vertical position onto the floor or a corresponding surface of a stair hall, and fillable with concrete; stair step elements fastened at their first end stepwise to the mast and branching off radially from the mast; at least one tubular stringer fastened to the second end of the stair step elements, fillable with concrete and connectable with fastening members to at least one wall of the stair hall, for supporting the stair step elements at their second end and for anchoring the staircase element to a building. The invention also relates to a method for building a staircase.

Abstract: An apparatus for turning and mixing a flat bed composting mass includes an even number of mixing worms that each rotate about a vertical shaft. The end of each vertical shaft may include a wear-resistant element on its end which serves to protect the shaft during operation. The vertical shafts may also be hollow and include an air hole for transmitting air into the composting mass. The pair of mixing worms preferably rotate in opposite directions to lift the composting mass upwardly from the bottom of the mass.