The Rio de Janeiro Line 4 is a subway line. It is part elevated and part underground (2 segments). The line has been planned to open for the 2016 Rio de Janeiro Summer Olympics.

Dextra has been involved since between 2013 and 2015 in the design, engineering and supply of four large FRP Soft Eyes for the station entry/exit points. Those Soft-Eyes were the first ever delivered in the South American continent.

Antes de la construcción de D-Wall, Dextra diseña el diseño de la jaula de FRP teniendo en cuenta el tamaño de la tuneladora, el margen de error, las fuerzas del suelo y más parámetros de diseño.

Thanks to the properties of FRP material, Tunnel Boring Machines cut through the D-Wall in a minimum time, saving time on schedule and ensuring the perfect condition of the TBM’s head. The time factor is especially important in humid environments such as Rio to limit the water entry into the station excavations.

On this project, Dextra also supplied Rolltec Rebar Couplers, used as vertical connections in the station diaphragm walls as vertical connectors to reconnect cages.

Couplers were also used horizontally to provide a reconnection point for slabs (at station level and at the surface) in the D-Walls.