Robots are being used in the works of the northern section of São Paulo Road Ring

High-tech equipment is used in tunnel construction under responsibility of the Spanish contractor Ossa

The Spanish company Ossa Obras Subterrâneas—specialized in tunnel construction—is responsible by the works of two tunnels in sections 4 and 5 of the northern section of Mario Covas Road Ring (SP-021), in a total length of approximately 1500 meters of underground works. The average advance is of one meter per day in each section. The purpose of these tunnels is to minimize the environmental impact in the Cantareira Hills—one of the more preserved areas of the Metropolitan Region of São Paulo (RMSP) that shelters unique species of flora and fauna and is one of the last remainders of the Mata Atlântica in the RMSP—that are crossed by the northern road section.

According to Luiz Gonzalo Garcia, engineer in charge of the tunnel works in the Road Ring, this work demands the use of high-tech features, since the drilling requires constant attention and a lot of planning. He explains that the type of soil found in Cantareira Hills has too much clay and rock and demands high-tech equipment to face and overpass these difficulties. To face the challenges demanded by the works, Putzmeister machines are being used successfully in the tunnel work fronts by approximately 50 persons. “Our company always used Putzmeister equipment, which matches our technical needs and ensures us safety and reliability”, says Ossa engineer.

With the robot, Putzmeister offers state of the art technology for tunnel shotcrete. The equipment, manufactured in Spain and designed by German engineers, makes construction processes safer and easier, since it is remotely operated and has mechanical arms that replace the shotcrete operator.

In addition, the equipment may spray up to 20 cu.mt. per hour. "We also provide the best solutions in concrete pumping and transport for underground works. As occurs in the Road Ring, our machines are present in the main works of this type that are being carried out in the whole country", explains the Putzmeister Underground sales manager in Brazil, Francisco Antunes Sousa.

In the Road Ring, robots spray a layer of about 5 cm of concrete on the tunnel walls to contain the structure that will receive the supporting beams later.

Container

A way to optimize works is to reduce at maximum downtimes for maintenance or even for parts replacement or repair. Thinking about that, the Aftersales Department of Putzmeister is making available new options to support its clients. A container with spare parts for the robots was installed in the Ossa worksite of the Road Ring’s northern section.

The Idea is that the contractor might have at its disposal a sort of mini-warehouse with the main components of the equipment, what will ensure speed and efficiency during preventive maintenance and repairs, and will be an appropriate storage place, free of moisture, heat and dust. "With this solution, we want to increase the performance in the processes of preventive maintenance and repair of the equipment ", says the aftersales director Felipe Rix Hrdlicka.

Northern Section, last part of the Road Ring

Mário Covas Road Ring (SP-21), also known as Metropolitan Road Ring of São Paulo is a 180-km highway having two runways and six lanes, that is being built around the Center of the Metropolitan Region of São Paulo. Its purpose is to reduce the intense traffic of trucks that come from the state inland and of several areas of the country and that have to cross the city through its two urban river border roads (Pinheiros and Tietê), causing huge congestion and pollution.

Works have their first section opened to the traffic in 2002. The northern section, the last to be finished, is scheduled to start to operate in 2016.

The northern section will be 44 km long with 12.26 km in tunnel. It will connect the western and eastern sections, allowing the access to Fernão Dias Highway (BR-381) and to Guarulhos Airport.