Millau Viaduct slightest movement in the Viaduct, and measure its resistance to wear-and-tear over time. Anemometers, accelerometers, inclinometers, temperature sensors are all used for the instrumentation network. Twelve fibre optic extensometers were installed in the base of pylon P2. Being the tallest of all, it is therefore under the most intense stress. These sensors detect movements on the order of a micrometre. Other extensometers, electrical this time, are distributed on top of P2 and P7. This apparatus is capable of taking up to 100 readings per second. In high winds, they continuously monitor the reactions of the Viaduct to extreme conditions. Accelerometers
Le Truel Le Truel Le Truel () is a commune in the Aveyron department in southern France. The village was in the ancient province of Rouergue where they spoke in the "rouergat" patois of Occitan. The commune is on the southern edge of the Massif Central. The hamlets to the north have commanding views of the Cevennes and the Millau Viaduct, which is to the west. The commune is approached along the D200 which connects it to the A75 autoroute. The D200 runs alongside the Tarn which has been dammed and provides the power for two hydro-electric generating plants, Jourdanie and Le