The cold recycling-express
Low cost and high quality are two of the most important criteria when it comes to rehabilitating roads. The WIRTGEN cold recycling train has yet another advantage: roads can be re-opened to traffic in no time. A WR 240 cold recycler and soil stabilizer demonstrated this advantage on a 22km-long job site near Hapur, where cars returned to the road after just 2.5 hours.
India // Hapur
The country road between Hapur and Kithore is one of the most important links in the Hapur district. It was in poor condition, with potholes, cracks and ruts, which were degrading the asphalt pavement. The decision was made to rehabilitate the road using the economical and resource-saving cold recycling method. In this process, a WIRTGEN pave train mills and granulates the damaged asphalt layers, binds the material again by adding binding agent, compacts it and then directly re-paves it. This is therefore referred to as an “in situ” method (performed in place). “We use all the milled material and process it specifically for this purpose, obtaining a high-quality construction material. We save a lot of time and money in this way, while minimizing the environmental impact,” says Mr Ram Kumar, Site Manager for the contractor, Seema Construction, in praise of cold recycling, a proven process worldwide that offers an excellent alternative to traditional methods. And he should know: this job site alone extends over more than 22km.
Rehabilitation method proven worldwide
Another important advantage of the cold recycling method is the fast turnaround: in most cases there is no need for a complete closure of the road. This was the case in Uttar Pradesh, where traffic continued to flow in the second lane. Each rehabilitated section of the country road was re-opened to traffic after just 2.5 hours, despite the fact that the cold recycling pave train does not simply pave a temporary surface, but rather a sustainably durable, high-quality, cold recycled layer. Different pavement structures and combinations of machinery are possible when employing this method. At the job site near Hapur, cement was first spread onto the damaged asphalt by an SW 16 MC binding agent spreader from WIRTGEN systems partner STREUMASTER, which was followed by a tank truck that supplied the WIRTGEN WR 240 cold recycler and soil stabilizer with water. The WR 240 is equipped with the new DURAFORCE milling and mixing rotor, which thoroughly mixed the damaged layers – i.e. the asphalt surface course as well as the binder and base courses – together with the pre-spread cement and added water in a variable mixing chamber and then redeposited the material. A grader then took care of the profiling and various HAMM rollers – in this case a 311 D compactor and an HD 99 tandem roller – compacted the new cold recycled layer. With its new surfacing, the recycled road has a high bearing capacity and a long service life. In the final step, a conventional surface course is usually paved on top as a wearing course.