HYDRAULIC SUPPORTING DEVICE
A hydraulic supporting device for supporting a first beam (52) on a second beam (53) has a pressure cushion (54) between the two beams. The pressure in the pressure cushion is variable but uniform over the whole length of the pressure cushion. The pressure cushion (54) rests on a contact surface on the first beam (52). The cross-sectional width (b) of the contact surface is less than the total width of the pressure cushion (54). A free space (55) into which a flexible tube of the pressure cushion (54) can penetrate is provided on each side of the contact surface.