Civil engineering machine and method for forming a hole

A civil engineering machine for forming a hole in the ground, comprising

• a machine frame,
• a holding device in an upper region of the machine frame for holding the civil engineering machine on a supporting cable or supporting rod,
• a removal device, which has at least one rotationally drivable removal element and is arranged in a lower end region of the machine frame and is configured to remove soil material,
• a drive arranged on the machine frame for rotationally driving the at least one removal element, and
• a suction device for suctioning removed soil material together with a liquid that is contained in the hole, upwards by means of a suction line, wherein the suction device comprises at least one suction opening in the lower end region of the machine frame and a suction pump, which is arranged on the machine frame,
• wherein the suction line ends in a distributing unit, which is arranged on the machine frame and to which an upwardly directed discharge line and a return line for returning a part of the suctioned fluid to the lower end region of the machine frame are connected, wherein
• the distributing unit has a screen, which is configured to pass through liquid containing smaller removed soil material either to the return line or to the discharge line,
• wherein the screen is configured to pass through a first partial stream of liquid containing smaller removed soil material to the return line, wherein larger soil particles, which are unable to pass through the screen, can be discharged upwards by the suction pump together with liquid via the discharge line in a second partial stream.