A3 Highway

  Customer:  Autostrade Meridionali S.p.A.

  Site:  A3 Napoli-Salerno Highway

  Project title:  Output-only modal identification   tests on nine highway bridges belonging to the A3   Highway

  Year:  2018

  Tags:  OMA


The S2X Teams carried out an extensive experimental campaign of output-only modal identification tests on 9 reinforced concrete highway bridges belonging to the A3 Napoli-Salerno Highway in the context of a wider program of structural safety checks.
The modal identification tests have been carried out on night time to minimize the impact on traffic. The ambient vibration response of the bridges has been processed by means of well-established procedures of Operational Modal Analysis implemented into proprietary software.

Overall, the experimental campaign involved 9 highway bridges, with the installation of 206 accelerometers and about 20 km of cables (approximately covering the distance between Nocera Inferiore and Salerno) in about 60 hours of field work including the 21 hours of data acquisition. After data processing, 65 modes have been identified (on average, 7 modes per bridge). Natural frequencies, damping ratios and mode shapes have been estimated for each tested bridge. The average time elapsed between test execution and delivery of the test report was 72 hours.


RAINIERI C., Notarangelo M.A., Fabbrocino G. (2020). Experiences of dynamic identification and monitoring of bridges in serviceability conditions and after hazardous events, INFRASTRUCTURES, Vol. 5(10), Article number 86, p. 1-23, DOI: 10.3390/infrastructures5100086.