Settlement cells Applications Settlement cells are used to monitor settlement and heave in soils.  Typical applications include: Monitoring settlement or heave in embankments and embankment foundations. Monitoring subsidence due to tunneling and mining. Monitoring consolidation under storage tanks. Monitoring settlement due to dewatering or preloading. Monitoring settlement in marine fills. Operation A  settlement cell consists of a liquid reservoir, liquid-filled tubing, and the  settlement cell, which contains a pressure transducer. One end of the tubing is  connected to the settlement cell, which is embedded in fill or installed in a  borehole. The other end of the tubing is connected to the reservoir, which is  located away from the construction area. The transducer measures the pressure created by the column of liquid in the  tubing. As the transducer settles with the surrounding ground, the height of the  column is increased and the settlement cell measures higher pressure. Settlement  is calculated by converting the change in pressure to millimeters or inches of  liquid head. Settlement cells are available with vibrating wire or pneumatic pressure  transducers. The vibrating wire version is easier to read, can be automated, and  provides a wider range. The pneumatic version is less expensive. Advantages The reservoir and readout station can be located away from the construction  area. The cell and tubing are buried and do not interfere with construction  activities. Vibrating wire version can be automated and provides good resolution over a  wide range. Limitations The system must be corrected for changes in temperature and barometric  pressure. Careful installation can minimize these effects. For best results, the reservoir should be pressurized, which adds expense.  The pressurized reservoir isolates the liquid from atmospheric pressure and  minimizes the formation of bubbles in the tubing.