Hot-In-Place Recycling for Beijing's Chang’An Avenue

completed

Chang’an Avenue, literally translated as “Eternal Peace Street”, links the most important political and cultural landmarks in Beijing, China. This bustling street is where you will find various government organizations, historical buildings like Tian An Men (The Forbidden City), and commercial centres like the Beijing Hotel. Every hour about 8,000 vehicles travel down the Avenue, but it had not been repaired for 10 years. The heavy traffic, combined with sporadic maintenance had led to many road defects like cracks, ruts, and potholes. Leading up to the 60th Anniversary of The People’s Republic of China in 2009, it was ordered that the road had to be renovated for the military parade during the National Day. Beijing Municipal requested local contractors to carry out the works with the requirement of “shortest time, best quality, and with minimum influence” during the repairs. As the road was so busy, both day and night, this created an exciting challenge to manage the timings, process, and the environmental impacts. Prior to the commencement of the project, Freetech undertook numerous tests to evaluate the accurate amount of rejuvenating agent and new bitumen content for the pavement repair. Based on their findings, Hot-In-Place Recycling was chosen as the best solution. Freetech’s technology fully utilized the old asphalt material by means of a Hot-In-Place Recycling Train, combing heating, scarifying, mixing, paving and compacting in one process. The patented intermittent radiation heating system easily met the environmental requirements as hot-in-place recycling is “clean and smokeless”. Specially designed scarifying rakes were used so the fully-heated pavement could be quietly scarified. The rakes did not break the aggregate, so the asphalt specifications were known and kept under control. The performance index of the finished pavement met all the required standards, just as good as a newly built road. To cope with the busy road, Freetech worked at night from 11:30pm to 5:30am. The transition length to and from the site was about 50km, so the high mobility of the Hot-In-Place Recycling Train saved much time during the entry and exit of the road site, and minimized interruption of the traffic. The Hot-In-Place Recycling Train work speed was up to 4 to 6 metres per minute, which was faster than that by traditional milling and paving. Freetech not only saved the time, but delivered the highest efficiency for Chang’an Avenue’s major overhaul, meeting and exceeding the requirements of “shortest time, best quality, and with minimum influence.”