Study On Detecting And Evaluating,Precauting And Controlling Key Technology Of Asphalt Mixture Segregation In The Seasonal Frozen Region

Construction segregation of asphalt mixture is one of the main causes of road early damage. The domestic research have studied the reasons of asphalt mixture's construction segregation in some projects, and proposed the corresponding control measures. However, there are difference among the material supply of all regions and technical levels of construction. The paper aims at current construction state of asphalt pavement in seasonal frozen region of Northeast, intensively studies the various factors that impact the construction segregation of asphalt mixture, carries out systemic research of the key technology of segregation control from material composition of asphalt mixture to construction link's control, and form a set of construction segregation prevention and control technology applied to different types of asphalt mixture in this region. The study has important directive significance and service value to prevent construction segregation of asphalt pavement, raise the uniformity of the road, and extend the life of the road.The paper relies on Ji Hun highway in Jilin, aims at the natural environment of the route, research the factors of creating aggregate segregation,temperature segregation,rolling segregation and aggregate-asphalt segregation in the production of a lot of asphalt mixture, from the design of asphalt mixture,the production and management of raw materials asphalt mixture's mixing,transport,paving,rolling at different stages. It uses drilling sample and non-destructive testing methods, exploit PQI non-nuclear densitometer and other advanced equipment, through a large number of indoor and field test data analysis, use structure with the depth ratio, porosity, asphalt-aggregate ratio difference, mineral aggregate gradation deviation to judge the degree of construction segregation of asphalt road in seasonal frozen region, and propose the multi-criteria criterion. It uses infrared thermal imager,metal probe thermometer and PQI non-nuclear densitometer, analyzes the influence of temperature segregation to density and porosity of asphalt pavement, and propose the discretion and controlling request of temperature segregation.In addition, the paper mainly studies how to improve aggregate gradation design,production control and stacking of raw materials,mixing equipment adjustments and improvements,transport and handling standardized,paving and rolling parameter settings,rolling processes optional regrouping and effective prevention and control of asphalt mixture construction segregation, propose a set of effective method applied to asphalt mixture segregation prevention and control in seasonal frozen region, and succeeds using to the project of asphalt pavement for the construction quality control.