Study On Old Asphalt Pavement Performance Evaluation And Maintenance Project Of Changsha Belt Expressway(Northwest Section)

The Changsha belt expressway(northwest section) is the first asphalt expressway in Hunan province, and has been operating for nearly 15 years. With the rapid growth of traffic and axle load, the asphalt pavement damage is increasingly serious, even had a severe functional damage and structural defects, and the service level is declining. The original pavement structure already can not meet the requirement of the rapid growth of traffic volume and vehicle load, and in urgent need of maintenance.Based on the current Highway technical condition evaluation standard and the existing research on this field, and the Changsha belt expressway(northwest section) pavement maintenance project as the background, comprehensive investigation and detection into the Changsha belt expressway(northwest section) was made. The single index and comprehensive index of pavement performance was evaluated, and its main diseases were analyzed. The pavement structure thickness was thin, and the stiffness and strength of pavement structure of part road was low. The high temperature stability of asphalt mixture was poor. Measures for dealing with the insufficient structure strength of base or subgrade were put forward to make pavement structure bearing capacity restore. Pavement repaving was proposed to restore the anti-sliding ability and flatness and repair surface damage.As we all know, one maintenance technical measure could deal with a variety of diseases. Under the precondition of technical feasibility and saving investment, the road segmentation for the Changsha belt expressway(northwest section) was made. The comprehensive treatment project of Hedong segment and Hexi segment was put forward.Based on the existing research, the way of the old asphalt expressway pavement maintenance plan forecast model, based on investment benefit, was put forward. The old asphalt expressway pavement maintenance plan forecast model, based on investment benefit, was established. The relationship between the investment benefit and aggregate investment, durable years, traffic was established. Besides, the model was introduced by an example.Reference to the research at home and abroad, the construction technology and the control points of construction quality of hot in-place recycling were put forward. Through the contrastive analysis of two different kinds of traffic organization scheme, the traffic organization scheme of the Changsha belt expressway(northwest section) was suggested to use semi width two-way traffic, ensuring the two-way road traffic capacity, and reducing the pressure on the regional road diversion. At the same time the specific preventive measures of traffic safety was put forward to avoid traffic accidents and traffic jams.