The AMTS collects settlement plate readings. The Gateway collects piezometer readings. Both send readings to the GeoCloud server at frequent intervals.
The server processes the readings and posts alerts, graphs, and reports on the Geocloud project website. Authorized users have access wherever there is an internet connection.
Advantages of Automation
- Automation reduces the need for instrument technicians and survey crews to visit the site, controlling costs and enhancing site safety.
- Automation obtains measurements at frequent intervals, increasing both reliability and confidence in the data.
- Automation presents data graphically on a secure website that is updated continuously.
Piezometers are installed at specified locations and depths within the wick drain grid. When ground conditions permit, the wick-drain rig is used to install the piezometers; otherwise, the piezometers are installed in boreholes. In either case, cable from the piezometer is brought to the surface.
Automation: Pore-pressure readings are automated by connecting a GeoCloud wireless node to the piezometer. Similar to a small data logger, the self-powered node reads the piezometer at regular intervals and transmits the data to the GeoCloud internet gateway.
Settlement plates are installed at specified locations within the wick drain grid. A basic settlement plate consists of a plate and a riser pipe that can be extended upwards as fill is placed. Settlement is traditionally monitored by surveying the top of the riser pipe.
Automation: Prisms are attached to settlement plate risers. An AMTS system measures the elevation of the prisms.
GeoCloud wireless nodes can also be mounted on the settlement plate riser: a node to monitor a piezometer installed at the same location; or a laser distance meter node to monitor the current fill level.
AMTS Monitoring System
The AMTS monitoring system is typically mounted on a gravity-base tower that provides line-of-sight to many settlement plate prisms. The AMTS obtains high precision elevation measurements at regular intervals and transmits them to the internet via a cellular modem.
The GeoCloud gateway forwards readings from Geocloud nodes to the internet via a cellular connection. It is often co-located with the AMTS.
Both the AMTS and the Gateway can be powered by solar panels.
The GeoCloud server receives measurements sent from the project site. It performs preprocessing operations, such as least-squares adjustments for the AMTS measurements, and then stores the data in a project database.
Each project has a dedicated website and automatically generates graphs, reports, and views such as the contour plot below. Authorized users can access the website with smartphones, tablets, and desktop computers.
This combination plot shows pore-water pressure (top) and settlement. Pore-water pressure increases as the surcharge is placed and then dissipates over time. Settlement follows the decrease in pore-water pressure and then shows a slight rebound when the surcharge is removed.
The settlement contours generated for this plot used data from settlement plates, shown as yellow diamonds. Red shows the least settlement, blue shows the most. The plot also shows data for piezometers, tiltmeters, and vibration monitors.