The structural response of Submerged Floating Tunnel to multi-support seismic excitations

Martire G., Esposto M., Faggiano B., Mazzolani F. M., Landolfo R., Zollo A., Stabile T. A.

In: R. Sause, F. Mazzolani and J. Ricles (Ed.) Behaviour of Steel Structures in Seismic Areas, CRC Press, Chapter 3, pp. 19-25, 2009 | doi: 10.1201/9780203861592.ch3 | ISBN: 978-0-415-56326-0

ABSTRACT:

In this paper the structural response of Submerged Floating Tunnels (SFTs) to seismic events is investigated. SFT is an innovative structural typology for waterway crossings, which consists of a tunnel placed underwater at a certain depth below the free surface and fixed in position by means of anchorage cables. Thanks to the deformability provided by the cables restrain condition, SFTs should represent a reliable solution for strait crossings even in high seismicity zones. Time domain dynamic analysis are carried out on different case studies, considering ground multi-support excitation determined through the generation of synthetic accelerograms by simulating the fault breaking mechanism. The main aspects of the structural behaviour are illustrated; results show the complexity of the seismic response of SFTs and, at the same time, give useful indications about critical aspects of the design.