Specifications

The flat dilatometer consists of a stainless steel blade with a thin flat circular expandable steel membrane on one side.

The flat dilatometer consists of a stainless steel blade with a thin flat circular expandable steel membrane on one side. When at rest, the external surface of the membrane is flush with the surrounding flat surface of the blade. The blade is jacked into the ground using a penetrometer rig or a ballasted drilling rig. The blade is connected to a control unit on the surface by a nylon tube containing an electrical wire. The tube runs through the penetrometer rods. At 20-cm depth intervals jacking is stopped and, without delay, the membrane is inflated by means of pressurized gas. Readings are taken of the A pressure required to just begin to move the membrane and of the B pressure required to move its center 1.00 mm into the soil.