Study On Asphalt Pavement Structure Dynamic Stability Controlling Standard Of Shi-an Expressway Extension Project

Rutting is one of the common diseases of asphalt concrete pavement and Anti-rutting performance controlling standard of asphalt pavement has already been a key issue studied by road workers.In this paper,full thickness rutting test was conducted based on field investigation at Shi An expressway.Then relationship between dynamic stability controlling standard and cumulative equivalent shaft of Shi An expressway asphalt pavement was established,adding that structure dynamic stability controlling standard of Shi An expressway's lane broadening and overlaying were determined.At first,cause of rutting disease was analyzed by collecting information such as original road traffic,climate temperature and rutting disease after field investigation at Shi An expressway.Test method of full thickness rutting was chosen to study asphalt pavement anti-rutting performance of Shi An expressway.Conditions of this method was as follows:test time of 60min,test load of 0.7MPa,wheel grinding speed of 42 times per min,specimen top temperature of 60?,specimen bottom temperature of 45.80?.After that,full thickness rutting test was carried out on multi-layer specimen obtained from original pavement.The result showed that:As the rutting depth with same section and lane changed,its corresponding shoulder structure's initial stability changed as well.the bigger the structure initial stability was,the smaller the corresponding main lane's rutting depth was;Relationship curve between structure's initial dynamic stability and main lane's rutting depth was established.Structure dynamic stability[DS]corresponding to allowable rutting depth[RD]?15mm was confirmed as control standard of anti-rutting performance under its relevant cumulative equivalent shaft.At last,rutting Appropriate equivalent axle load conversion model and rutting forecast model was chosen to estimate relationship between relevant cumulative equivalent shaft of current year as well as end of design life and dynamic stability controlling standard for Shi An expressway.Anti-rutting performance control standard,which was suitable for Shi An expressway's lane broadening and overlaying,corresponding to relevant cumulative equivalent shaft was suggested.