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
San Joaquin River Viaduct San Joaquin River Viaduct The San Joaquin River Viaduct is a bridge currently under construction to carry California High-Speed Rail over the San Joaquin River. Most of the bridge is in the city of Fresno, California in Fresno County, although the portion north of the river will be in Madera County. It is the second major river crossing to be constructed as part of California High-Speed Rail, after the Fresno River Viaduct to the north. The bridge will be long, and combines a double concrete arch span crossing the river with a pergola structure to carry the tracks laterally over