Dynapac fleet compacts earthworks at Brazil's Jirau dam megaproject

A new Brazilian-built Dynapac CT300 static tamping roller is amongst the fleet of Dynapac equipment being used by contractor Camargo Correa on the massive Jirau hydroelectric project now under construction on the Madeira River in north-western Brazil.

One of the primary functions of the articulated machine, which is fitted with padfoot drums to the front and rear, is to compact the soil that will form the floor of the reservoir which will build up directly behind the dam.

The Jirau project, which will have a capacity of 3,450MW generated by 46 turbines, is currently the largest hydroelectric scheme under construction in the Americas.

Construction is being undertaken by the consortium ESBR Sustainable Energy of Brazil, formed by companies GDF Suez of France(50.1 percent), Eletrosul (20 percent), Chesf (20 percent) and Camargo Correa (9.9 percent). Camargo Correa, one of Brazil's largest contractors, is undertaking the civil works.

Jirau, together with the Santo Antonio hydroelectric project being constructed adjacent on the same river, where a fleet of Dynapac machines is also working, is considered a crucial element for the future supply of electricity in Brazil.

Camargo Correa purchased the Dynapac machines via Atlas Copco Brazil, which is headquartered in Sao Paulo.

The fleet includes compactors built at Dynapac's manufacturing plant at Sorocaba, in Sao Paulo State, Brazil, along with Swedish-built machines.

The CT300 is the only one of its kind on the site, the other models being mainly CA600 single-drum vibratory compactors.

Luiz Paulo Santos, Camargo Correa's manager for mobile equipment, said that the CT300 was chosen for its manoeuvrability and speed of working, as well as for its high availability to the work.

The compactor weighs 21 t and is specifically designed for compacting cohesive or semi-cohesive soils over large areas. As a static tamping roller, high speed is required for optimum compaction, and the CT300 can travel at a maximum speed of 21 km/h, forwards and backwards.

Each of the four drums is fitted with 60 pads, the pads being 185 mm high and having a contact area of 200 sq cm, adding up to an average production capacity of 800 cu m per hour.

With a steering angle of 40 degrees to either side and a turning radius of 6.3 m, the machine can work fast around other equipment and cope with irregular areas.

The Madeira River is the largest tributary of the Amazon, with Jirau located 130 km from the nearest town, Porto Velho. The Santo Antonio project is located just 5 km outside of Porto Velho.

Jirau will have a rockfill dam 35 m high and 550 m long, flanked by two compacted earthen dikes, one 930 m long and the other 1,140 m long. The reservoir will cover an area of 258 sq km. Powerhouses on each bank will house the turbines.

Jirau's massive site employs an estimated 16,000 workers, most of whom are housed in camps at the site itself, and work is being carried out on a 24-hour basis.

Work began on Jirau in 2008 and power generation is expected to begin in 2012. The project is expected to operate at full capacity by October 2016.

For further details please contact:

Lotta Bynke, Dynapac AB
 lotta.bynke@se.atlascopco.com

Dynapac is part of the Atlas Copco Group within the Atlas Copco Road Construction Equipment division. We are experts on asphalt, soil and concrete applications, committed to customer performance worldwide. Products and solutions are marketed under the Dynapac brand and complementary brands. Headquartered in Stockholm, Sweden, the division has production facilities in Europe, USA, South America and Asia.