The Temporary Business Association established by Field S.r.l. and Agisco S.r.l. was commissioned by the Liguria Region to draw up a continuous and remote topographic, instrumental, environmental and vibrational monitoring project on a section of the Polcevera Viaduct, called the Morandi Viaduct, as a result of the collapse of one of its parts on August 14, 2018. The project involves the monitoring of the Ponente viaduct section (monitoring of the batteries from N ° 3 to N ° 8) and of the Levant viaduct section (monitoring of the N ° 10 pile).
The monitoring project is divided into four distinct types:
• Environmental: for determining the speed (minimum, average and maximum), wind direction, relative humidity and average air temperature;
• Dynamic: for determining the vibrational state of decks and stacks with the determination of the significant parameters useful for the numerical modeling of the viaduct;
• Instrumental: for determining the variations of rotations of decks and stacks;
• Topographic: for the determination of deformations in the space of decks, stacks and stays.
The environmental monitoring system consists of a thermo hygrometer to measure relative humidity and air temperature, and an electronic anemometer to measure wind direction and speed.
The dynamic monitoring system consists of a series of triaxial accelerometers arranged along the stays and on the deck of stack N ° 10 of the Levant section of the viaduct, to determine the characteristics of speed, acceleration and frequencies of the structure.
On the stack, 12 triaxial accelerometers with a measuring range of ± 2 G (6 for each of the two sides) have been provided.
The instrumental monitoring system consists of a series of biaxial clinometers and monoaxial electrolivels arranged along the bridge, the piers, the antennas and the viaduct strands. To monitor the Ponente section were installed 70 wireless biaxial clinometers, for the instrumental monitoring of the N ° 10 stack of the section at Levante were installed N ° 52 single-axial electrolytic electrolytes.
The topographic monitoring system consists of a series of topographic prisms arranged along the bridge, the piles, the antennas and the viaduct strands.
The planned topographic network foresees the installation of 4 very high precision robotic total stations for automated topographic measurements that correspond to a total of 135 prisms located along the viaduct.