After 70 years, road PA-150 is paved with cold recycling technique
Since its opening, 70 years ago, the road that connects the city of Belém to the countryside of the state of Pará, PA-150, receives a complete recovery of its pavement for the first time. Started in August 2013, the project is undertaken by the companies CFA construções, Terraplanagem and Pavimentação Ltda along with Ameta Engenharia Ltda.
The tendered stretch is 12 meters wide, in lane and shoulder, and it extends from the city of Jucundá, KM 308, until Morada Nova, KM 414.
The in situ cold recycling technique was used for renewing the lane, which reduces the demand and transportation costs in over 95%. The option, besides being ecological, is also the fastest and most advanced one in view of other milling processes because it uses less oil derivatives.
The cold recycling process allows several types of applications from thinner to thicker layers. The technique consists of recycling the crushed brash and using it in the mix of the new asphalt.
Some of the advantages are the precision in the application of stabilizing agents and consequently more homogeneous layers. In addition, due to the lower time of duration of the jobs, the costs are lower and there is less interference of the equipment on the roads.
Expected to be completed in December this year, the job is divided into three steps: asphalt restoration, shoulder construction, and signaling.
Among the equipment used are two WR 240 cold recyclers and two WR 2400. According to José Irineu Ramos Júnior, comercial manager at Deltamaq, representative of the Wirtgen Group in the Amazon and region, "the WR 240 is an evolution compared to the previous generation, the WR 2400". It has several technical advancements, such as total view of the job with lateral displacement of the operator cabin, rear camera, smaller turning radius for jobs in urban spaces and possibilities of using up to nine different cutting speeds according to the type and hardness level of the material to be recycled. The recyclers by Wirtgen are the only ones in the market which have independence between the recycling box and the machine's chassis".
Asphalt plants UACF 17 P1 and UACF 17 P2 are also in the project. Both with a yield capacity of 120 tons per hour, they present a precise dosage of aggregates and filter over 99.5% of the particle materials.
The Vögele Super 1100-2 and Ciber AF 4500 Pavers are also part of the road recovery job, as well as Hamm Compacting Rollers 3411P and 3411.
- Recyclers WR 240: with a total weight of 29,400 kg and a powerful engine of 455 kW/619 PS, the recycler operates at a depth of up to 510 mm in nine cutting speeds which can vary according to the hardness of the material to be recycled. With a work width of 2400 mm and easy execution, it produces uniform layers in a shorter time. The machine, with four-wheel drive, also has a rear camera and a smaller turning radius, recommended for operation in urban areas.
- Asphalt plant UACF 17 P: With a yield capacity of 80 to 120 t/h, the equipment has silos which store between 30 and 40 tons of asphalt. It also has 144 bags of laminate polyester, responsible for excellence in particle filtering - product of a dosage system with a belt which requires little maintenance. Its counterflow system ensures drying, heating, and gradual pre-homogenization of the aggregate materials. UACF 17 P asphalt plants are easily adaptable to several climate conditions.
- Vögele Pavers Super 1100-2: to ensure the paving quality, the equipment has a vibrating screed with an electric system to heat the materials and a yield capacity equivalent to 300 t/h. With a base width of 1.85 meters, the spreading of the asphalt material reaches up to 4.2 meters.
- Ciber Paver AF 4500: it presents a paving capacity of 300 t/h and a silo which stores up to 10.5 tons of asphalt. Its compacting screed receives the materials in an optimal flow, which allows paving of up to 4.5 m at a maximum speed of 30 m/min.
- Hamm compacting roller 3411 with a vibrating smooth drum and 3411P with a vibrating padfoot drum: Weighting 11,310 kg and 11,800 kg, respectively, the rollers have hydrostatic steering and long maintenance intervals. With the same 2,140 mm of working width, the differential is on the drums. Recommended for compacting more cohesive soils, the 3411P model has as its highlights 140 padfoot segments on a 15 mm thick drum. The model 3411 with a 25 mm smooth roller is more used in jobs with granular materials. The results are uniform layers with optimal thickness for each job type.