Arian Ghasemi - PhD Student, Civil Engineering Faculty, Science and Research Branch
Esmaeel Gholizadeh - PhD, Geotechnical Engineering, Abfan Consulting Engineering

Considering the development of the use of tunnels in urban spaces, it is crucial to investigate their seismic behavior. One of the methods of seismic isolation in tunnels is the use of geofoams. This research investigates the geofoam layer's effect on the circular tunnel's seismic behavior using a numerical method. The results showed that geofoams lead to the reduction of displacement, structural effort, and seismic pressure on the lining. But their effect is more significant in movements with lower input acceleration. The effectiveness of geofoams is a function of their thickness, type, and location.

Geofoam, Seismic response, Tunnel, Numerical method, Seismic isolation