Definition - What does Piezometer mean?
Piezometers are instruments installed in small diameter bore holes that are dug in construction sites for monitoring the piezometric water level or pore water pressure. The piezometer works on the simple principle of a riser pipe with a perforated filter tip. In trenchless technology, the piezometer is used to carry out tests to determine the feasibility of carrying out projects in difficult areas.
Trenchlesspedia explains Piezometer
The tip of the piezometer is placed within gravel and sealed with bentonite above and beneath the gravel zone to isolate the pressure at the tip. Grout is used to fill the gap between the riser pipe and the borehole to prevent water from rising up the sides. The ground water pressure pushes the water up the riser pipe. The pore water pressure is equal to the height of the water in the riser pipe. The water level measured in the piezometer indicates the pore water pressure at the filter tip. Installing piezometers is especially important in offshore projects that require slope stability to prevent hazards. This method is a great way to know sub soil geo hazards in carrying out sub surface construction using trenchless technology. Offshore drilling operations and sub-surface drilling are costly operations and piezometers help in saving cost and time.