China's Roads Benefit From Wirtgen's Bitumen Stabilized Paving Recycling Technology

Technology from Wirtgen China is reducing the carbon footprint associated with reconstructing China's roads and providing road users with a more durable highway resulting in less traffic disruption.

Beijing, China (April 20, 2010) /ChinaNewswire.com/ — More and more cities and highway authorities in China are benefiting from Germany-based company Wirtgen's bitumen stabilized paving recycling technology, which conserves energy, reduces the demand for new materials, and produces a more durable road surface.

Wirtgen's recycling technology involves milling the existing road paving material and then mixing with an emulsion or foam of bitumen suspended in water together with a small amount of cement or lime. The bitumen acts as a flexible binding agent coalescing the milled particles together and also limits the ingress of water into the road base since the hydrophobic nature of bitumen inhibits water entering a layer of well-compacted material. Water entering the road base is a major factor in causing roads to deteriorate, particularly in parts of China that are subject to hot wet summers and freezing winters.

Initially regarded as a "poor man's" asphalt concrete, field performance has proved the case to be different and only recently have the non-continuous binding properties of these materials been appreciated. Results emanating from applied research efforts (primarily in South Africa, the Netherlands, and the USA) are now providing an understanding of the behaviour of these materials (particularly the non-continuously bonding) and their potential. The results of these studies suggest that the energy consumption associated with relaying a road can be reduced by a factor of up to three compared to older and more conventional technologies. In addition the grater durability of roads laid with this technique further reduces the expense and energy consumption associated with road repairs.

The adoption of this technology by the Chinese road authorities for rehabilitating their expressways that has opened up new research avenues which promise to be larger than everything done to date. Intentions to employ recently acquired accelerated testing facilities on these pavements are encouraging as they can only result in a better understanding of these materials, thereby advancing the technology.

The Yunnan Highway Bureau, for example, has successfully used three Wirtgen WR2500S units and a KMA200 unit, in their rehabilitation of the national highway network. This 800,000.00 square meters recycling job will be completed this year and the road owner is expecting to make cost savings of 30% compared to conventional methods. And Xi'an is using two Wirtgen WR2500S units on their municipal road rehabilitation. Changan Road in the city was repaired in 2009 with cost and energy savings combined and the benefit of reduced disruption to traffic due to a faster turn-round.

About the Wirtgen Group
The Wirtgen Group is an internationally operating group of companies in the construction machinery sector incorporating four traditional brands: Wirtgen, Vogele, Hamm, and Kleemann. As a technological leader, they offer their customers mobile machine solutions for road construction and road rehabilitation, as well as for mining and processing minerals.

The Wirtgen Group has been present in China for more than 20 years and, since 2004, has operated an assembly factory in Langfang, Hebei Province. With more than nine branches and 200 employees, Wirtgen China are always close to their customers.

For more information: www.wirtgen-china.com.cn