The SSG consists of a vibrating wire or fiber optic pressure transducer housed in a corrosion-resistant stainless steel body. The housing is normally attached to a base plate and connected to a reference station by a twin tubing filled with water (or anti-freeze solution) and fitted with connectors. The reference station consists of a liquid-filled reservoir open to atmospheric pressure and located at a known elevation. The settlement or heave is measured relatively to the elevation of the reservoir.
The SSG is robust and stable. It can be installed in boreholes, standpipes, soil or concrete. The settlement gauge can also be attached to structures for monitoring settlement. To ensure maximum performance, the twin tubing should be flushed at regular intervals to remove air bubbles, and data should be compensated for temperature changes and changes in atmospheric pressure. For best results, de-aired water or antifreeze solution is recommended.