Tunnel inventory of Grand Canary Island (Spain), geology and associated geotechnical problems

Abstract

In the last two decades more than 30 road tunnels has been built in Grand Canary Island, using a variety of construction methods and reaching a total extension of 14.66 km. They are 156 to 1200 m long, with an average length of 458.20 m per tunnel. The inventory of tunnels includes basic design data (i.e., geometry, widths and number of lanes, velocity), geological formations and materials and the most relevant geotechnical problems. The article shows three tunnel examples which were excavated in different volcanic rocks: (1) Basanite pyroclast and lava flows in the Tafira ring road (GC-4); (2) Phonolite lava flow and agglomerates at La Laja (GC-1); and (3) Phonolitic, trachytic and rhyolitic ignimbrites and lava flows at Arguineguin-Puerto Rico stretch (GC-1). It is intended that this tunnel inventory could be useful for future projects and works in the Canary Islands.