Patent ID: 7942607

Claim:
An underwater tunnel ( 6 ) connecting two land masses ( 2 a , 2 b ) separated by a body of water ( 3 ), the tunnel ( 6 ) comprising: an elongate shaft ( 10 ) having generally convex upper and lower outer surfaces ( 12 , 13 ) intersecting along longitudinally-extending, transversely opposed first and second sides ( 14 , 15 ) tapering in opposed directions away from a longitudinal axis of the tunnel ( 6 ); upper and lower vehicle apertures ( 20 a , 20 b ) extending longitudinally through a central portion of the shaft ( 10 ) for passage of vehicular traffic through either one of the vehicle apertures ( 20 a , 20 b ), the upper vehicle aperture ( 20 a ) extending parallel to and above the lower vehicle aperture ( 20 b ) and each of the vehicle apertures ( 20 a , 20 b ) sized to accommodate at least two lanes of traffic; and a tether ( 30 ) coupled between the shaft ( 10 ) and a bed ( 4 ) of the body of water ( 3 ) to maintain the shaft ( 10 ) at a generally uniform depth below a surface ( 5 ) of the body of water ( 3 ); wherein the shaft ( 10 ) comprises a plurality of longitudinally interconnected sections ( 11 ), each section ( 11 ) integrally formed of reinforced concrete to provide both ballast and structure for the shaft ( 10 ), and wherein a combined weight of the shaft ( 10 ) and an expected vehicular load in the shaft ( 10 ) is equal to or less than a weight of water displaced by the shaft ( 10 ).