Tunnel supported on bearing blocks

Abstract

The tunnel supported on bearing blocks is a tunnel to be executed in weak soils, which is constituted by two tubes: an exterior tube, formed by precast elements, which are mounted by a tunnel boring machine, and an interior tube, which is built using the exterior one as the exterior formwork and constitutes the resistant element of the tunnel, both being supported by bearing blocks, regularly spaced along the axis of the tunnel. The bearing blocks are extended downwards until the stiff soil through resistant elements with great horizontal flexibility in order to resist vertical loads, while allowing for horizontal movements of the tunnel during an earthquake.

1 . (canceled) 
   
   
       2 . (canceled) 
   
   
       3 . Tunnel to be executed in weak soil, being formed by two tubes: an exterior tube which is built by a tunnel boring machine and acts as exterior formwork, and an interior tube, which is cast inside the exterior one with the help of an interior supplementary formwork and possesses the longitudinal and transversal reinforcements of the tunnel. 
   
   
       4 . Tunnel according to  claim 3 , including disposing of concrete blocks, regularly spaced along the axis of the tunnel, which are extended downwards until the stiff soil through piles with great horizontal flexibility.