Faster Connections with DYWIDAG Systems: Metro Line 4 in Rio de Janeiro
The Metro system in Rio de Janeiro, Brazil, currently has a length of 40.9km and consists of Lines 1 and 2. Line 3 is being planned, and beginning in 2016, the new Line 4 will be operative. Line 4 will run from the city’s south west to the city center, where it will connect with Line 1. Once completed, the new line will have seven stops and transport 425,000 passengers per day in order to bring relief to the city’s west, where population has been steadily increasing.
The construction of a tunnel that will connect the stations of São Conrado and Jardim Oceânico is one of the biggest challenges in this project. Running under a hill with an overburden of 850m, the 8m high tunnel will be between 8 and 15m wide.
As São Conrado Station is at the foot of an unstable hill that is prone to landslides, comprehensive stabilization work had to be carried out in this area. Several retaining walls were built for stabilizing the tunnel portals. In addition, weathered rock formations were stabilized using mesh and anchors.
The corrosion protected DYWIDAG Bar Anchors supplied by Protendidos DYWIDAG were installed 6 to 30m deep into the rock and grouted using cement suspension. The bar anchors are fitted with post grouting tubes connected to the PVC tubes of the anchors and can thus be re-grouted to increase their carrying capacity at a later stage if necessary.
In addition, Ø 32mm DYWIDAG Bars were produced and supplied for stabilizing Jardim Oceânico Station. The bar anchors were epoxy coated due to aggressive soil conditions. Up to now, 4,038m of DYWIDAG Bar Anchors in average lengths of 12m have been installed.