Luda Yana Dam, Bulgaria

The dam is an earth-filled embankment dam with a clay core as watertight element; the shoulders will be made of river sandy gravels. The reservoir will contain about 20 million m³ of water. The length and height of the crest will be about 400 m and 30 m respectively.

Aim of monitoring:

A SHM system will be installed for monitoring the dam’s behavior during construction, first impoundment, and operation phases. The instruments will be installed inside or on the surface of the dam’s body, in the foundation, on the abutments, and close to the downstream toe of the dam.

During construction, all measurements will be taken manually with portable dataloggers like MB-3TL, and devices like the CPR-6 Water Level Indicator and the R-4 Magnetic REED Switch Probe Extensometer. Once construction will be completed, all sensors will be read automatically by a powerful Data Acquisition System- able to manage more than 100 sensors – located in the control room. All data will be stored in a database, called SDB, which provides a simultaneous display of several views on each sensor; the display can be of a tabular or graph plot with associated options such as thresholds plot, colors and sounds on alert, software actions on alert (e-mail, SMS).

Movements within the embankment and the foundation will be measured with inclinometers and settlement gauges. Pore water pressures within embankment and foundation will be measured by means of piezometers and observation wells. Several water level indicators will be installed in the reservoir. Stresses within the embankment will be controlled with total pressure cells. Due to earthquake’s risks dynamic measurements with accelerometers are considered too. A weather station completes the system.