TY  - JOUR
PY  - 2021//
TI  - Long-term monitoring of a tunnel in a landslide prone area by Brillouin-based distributed optical fiber sensors
JO  - Sensors (Basel)
A1  - Minardo, Aldo
A1  - Catalano, Ester
A1  - Coscetta, Agnese
A1  - Zeni, Giovanni
A1  - Di Maio, Caterina
A1  - Vassallo, Roberto
A1  - Picarelli, Luciano
A1  - Coviello, Roberto
A1  - Macchia, Giuseppe
A1  - Zeni, Luigi
SP  - e7032
EP  - e7032
VL  - 21
IS  - 21
N2  - This paper shows the results of the monitoring of the deformations of a tunnel, carried out using a distributed optical fiber strain sensor based on stimulated Brillouin scattering. The artificial tunnel of the national railway crosses the accumulation zone of an active landslide, the Varco d'Izzo earthflow, in the southern Italian Apennines. Severely damaged by the landslide movements, the tunnel was demolished and rebuilt in 1992 as a reinforced concrete box flanked by two deep sheet pile walls. In order to detect the onset of potentially dangerous strains of the tunnel structure and follow their time trend, the internal deformations of the tunnel are also monitored by a distributed fiber-optic strain sensor since 2016. The results of the monitoring activity show that the deformation profiles are characterized by strain peaks in correspondence of the structural joints. Furthermore, the elongation of the fiber strands crossing the joints is consistent with the data derived by other measurement systems. Experiments revealed an increase in the time rate of the fiber deformation in the first and last part of the monitoring period when the inclinometers of the area also recorded an acceleration in the landslide movements.<p />  <p>Language: en</p>
LA  - en
SN  - 1424-8220
UR  - http://dx.doi.org/10.3390/s21217032
ID  - ref1
ER  -