A WIRTGEN GROUP COMPANY

Cold recycling Leading technology in structural road rehabilitation One of the major north-south routes in the eastern United States of America runs across the state of Virginia with two lanes in each direction - Interstate I-81. Having been built in the late 1960s, I-81 had been in service for well over forty years. And time had not passed without leaving its mark on the heavily frequented highway. Continuously increasing traffic volumes and in particular the loads imposed by heavy-vehicle traffic had taken a heavy toll on the road pavement and caused damage to varying degrees. As a result,...

lower loads, the left-hand lane was to be rehabilitated by cold recycling to a depth of 12 cm. In this highly challenging construction project, rehabilitating the complete pavement structure involved the use of as many as three different recycling methods. All the more reason for VDOT to rely on the tried-and-tested high-performance machines from the Wirtgen Group and use powerful cold milling machines and cold recyclers, a mobile cold recycling mixing plant from Wirtgen and an entire fleet of Hamm rollers to breathe new life into the age-worn road. REHABILITATION OF THE RIGHT-HAND LANE Remove...

Off to a perfect start: the W 210 cold milling machine showed its mettle when excavating the right-hand lane at full depth. A big help in this truly demanding job: LEVEL PRO – the levelling system specifically designed by Wirtgen for use in cold milling machines precisely maintained the selected milling depth. At the same time, the powerful conveyor systems of the two cold milling machines kept the waiting trucks busy. The trucks transported the reclaimed granulated material to the mobile mixing plant, which had been set up in the vicinity of the construction site, for recycling and subsequent...

2 | The high-performance KMA 220 mobile mixing plant set up in the vicinity of the construction site produced high-quality cold mix. Preliminary investigations using the Wirtgen WLB 10 S laboratory plant enabled the foamed bitumen quality and, in combination with the Wirtgen WLM 30 laboratory mixer, the optimal mix proportion to be defined even prior to the start of construction. The powerful twin-shaft continuous mixer of the KMA 220 transformed the source material and the two additives into a homogeneous cold mix of high quality that was directly discharged into a waiting truck via a loading...

1 | The 3800 CR recycled the subgrade in a single pass while adding foamed bitumen to the process. 2 | Hamm tandem and pneumatictyred rollers quickly and reliably compacted the lefthand lane previously produced in an “in-situ” process. REHABILITATION OF THE LEFT-HAND LANE Following completion of the right-hand truck lane, the second project phase was next on the agenda: rehabilitation of the left-hand traffic lane. As it had mostly been used by passenger cars in the past, it was not as severely damaged, meaning that it also required less extensive rehabilitation methods. Similar to the rehabilitation...

It is a major advantage of the “in-situ” recycling process that neither the source material nor the recycled construction material mix require any transport effort. Preceding tanker trucks delivered bitumen and water to the 3800 CR via hose connections. The cold recycler milled off and granulated the damaged asphalt layer down to a depth of 12 cm in a single pass – while the milling and mixing rotor mixed in foamed bitumen, cement and water at the same time. Foamed bitumen was produced by the 3800 CR by injecting water and compressed air into hot bitumen. The precise mix proportion was again...

Wirtgen GmbH Reinhard-Wirtgen-Str. 2 · 53578 Windhagen · Germany Phone: +49 (0) 26 45    31-0 · Fax: +49 (0) 26 45    31-392 /1 /1 Internet: www.wirtgen.com · E-Mail: [email protected] Illustrations and texts are non-binding and may include customized fi ttings. Subject to technical changes. Performance data depend on operational conditions. Nr. 2464764 EN-01/16 © by Wirtgen GmbH 2016.