The Application Of Anti-Rutting Skeleton Type Hot Mixture Asphalt Optimization Design In Cha-Zha Highway

Qiqihar is a flat region with average elevation 146 meters.The winter of Qiqihar is very long and cold.As a result,the temperature difference between winter and summer is bigger.Moreover,as the passenger and cargo carrying capacity greatly rise year by year,the original gradation design method cannot meet the requirements of service performance,the existing rutting damage is relatively serious,and highway maintenance cycle is shorten,which in turn reduce the service life.Based on the real situation of the regional climate and traffic volume,the gradation design methodology suitable for the proposed region is researched here,to improve the anti-rutting capability of highway.Firstly,the existing design methods and construction schemes of various asphalt mixtures at home and abroad are counted,and then the Marshall Standard compaction,rotary compaction and vibration compaction are compared and studied.Through the analysis of test data,Marshall Standard compaction is determined to be the best molding method.Secondly,according to the structural and performance characteristics of HMA,different coarse aggregates,fine aggregates and fillers are selected to be mixed with asphalt and other materials to form different test pieces.Through the determination of service performance and mechanical parameters of different test pieces,the optimum grading scheme is determined eventually.Finally,after determining the suitable grading scheme,the best construction scheme is chosen according to the site construction and environmental conditions,taking into full consideration factors,such as temperature,equipment,transportation,paving and so on.The design and construction process of asphalt pavement at extreme cold climate for Qiqihaer area were concluded by researching gradation designs of skeleton-type HMA,and were applied to the national road from Qiqihaer to Nahe K99+410~k99+650 with a 240 m experimental road constructed.Base on in-field performance testing of this road after two years used as well as comparing with the original design method and construction scheme,the results show that anti-rutting performance is significantly improved,and its durability is also greatly improved,which in turn will extend the maintenance cycle.