Major earthquakes will cause multi-hazard issues for tunnels. Yet, advantages associated with it in terms of sustainability, time, land and fuel saving have made tunnels a vital option in modern cities. Double-arch tunnels are generally accepted for their effective and economical solutions as they have significant advantages in adjusting to the characteristics of the region and environmental safety. Experimental, numerical and analytical studies had been conducted by the researchers to understand its static and dynamic behavior. In the present study, authors have categorized and critically summarized the researches on double arch tunnel. It is essential for platform of higher research and development in this field.

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Tunnels are a major underground structure used for transporting passengers, water, wastewater, etc. Design of a tunnel/twin tunnel requires fixing the spacing between tunnels, assessment of hazards to surface structure due to tunnelling and protection measures, etc. Experimental, numerical, analytical methods or a combination of the above techniques are used to design and investigate the stability under static and dynamic conditions. Ground settlement due to tunnel construction, the spacing between the tunnels, the tunnel response during earthquake loading, influence of alignment, etc., have been reviewed and summarized from the past published literature. A summary of the different design criteria for twin tunnels is reviewed and presented here. The present paper will be helpful for engineers and researchers working in this area.