Wirtgen technology in Brazil – Slipform paver SP 850 modernizes motorway in Fortaleza

Since the deep-water port in Pecém – some 60 km from Fortaleza – was inaugurated in 2002, the city has become the primary port for exporting fruit products in refrigerated containers. Fuel and liquefied gas, fertilizer and steel products are also transshipped here. As a result, an immense number of heavy goods vehicles use the road to and from Fortaleza, the capital of the federal state of Ceará and Brazil's fifth largest metropolis with a population of more than 3.3 million inhabitants.

In order to manage this traffic volume, the port of Pecém has drawn up a logistics plan which also includes modernization of the Anel Viário de Fortaleza. It is hoped that this move will restore the smooth flow of traffic through the metropolis. Federal authorities have invested more than R$ 200m Brazilian Reais (R$) in the construction project, which is being executed by the contractor Galvão Engenharia S.A.

The motorway ring is to be modernized over a total length of 32.1 km by June 2015. At present, the road is 11 m wide. When the work is completed, each roadway will be 16.5 m wide. Measuring 33 m across its entire width, the road will hence be three times as wide as before the work started.

Due to the high degree of stress from heavy goods vehicles, the mechanical stability required of the new pavement was a major criterion prompting Galvão Engenharia S.A. to opt for concrete surfacing. An asphalt wearing course will then be laid over the concrete.

"The concrete foundation consequently has an average service life of 30 years, as compared to roughly six years for an asphalt course. The maintenance costs for this type of construction are hence a great deal lower," explains Thiago Henrique Menezes, an engineer with Galvão Engenharia.

"After reviewing various concrete projects in Brazil, we decided that the Wirtgen slipform paver SP 850 had the best credentials for the tasks in hand. Precision and productivity are the key advantages of this robust machine, which produces roadways of a superb quality," adds Menezes.

The SP 850 slipform paver is the ideal candidate for the production of all manner of high-quality concrete pavements. Main applications include the paving of urban roads, motorways, airport runways, “slab track” and hydraulically bound base courses. The hydraulically telescoping machine frame can be extended by 1.25 m to the left and to the right, permitting the use of paving molds ranging from 2.5 m to 5 m in width. Working widths of up to 10 m can be achieved by mounting additional extension elements. All components can be adjusted to the specified paving width.

Four separately hydraulically driven, steerable track units ensure excellent maneuverability and traction. The range of equipment includes spreading auger or spreading plough, dowel bar inserter, central tie bar inserter, side bar tie inserter, finishing beam, super smoother and 3D interface.

The entire paving process is automated from the even distribution of the concrete to its final smoothing: First, concrete is distributed by either a spreading auger or spreading plough. The heavy-duty paving mold then forms the concrete slab as the machine moves forward. Up to 24 curved high-frequency electric vibrators simultaneously ensure the optimum compaction of the concrete. Dowel bars, central tie bars and side tie bars can be inserted into the freshly placed concrete. A hydraulically driven hoisting crane for dowel or tie bar packages makes the process even easier. Finally, the finishing beam and super smoother ensure an exceptional finish.