Performance Optimization And Production Application Of Cold Patching Asphalt Mixture

With the increasing of road mileage in China,the work of road maintenance is increasing.China's road concept has been changing,from the initial "building for maintenance" to"building for maintenance",and then to the current "maintenance priority" concept,gradually increasing the status of maintenance and repair.As a kind of road mending material,the cold patching material shows its superiority for the situation that there are some small areas of potholes on the road surface.Especially in the autumn and winter season in Northeast China,the common hot mix asphalt mixture is limited,and the application of the cold patching material is more extensive.In this paper,we developed the cold make-up liquid independently,and explained the production factors of the cold make-up liquid accurately,such as the type and measurement of additives,the order of adding,the speed and temperature of stirring,which laid the foundation for the production and application.Under the background that the evaluation index of cold make-up liquid is not perfect,this paper selects the cold make-up liquid from two aspects:the performance of cold make-up liquid itself and the performance of cold make-up material,and finally obtains the optimal cold make-up liquid.Based on the Mohr Coulomb theory,this paper deeply analyzes the structure of cold patching asphalt mixture,and finally selects SMA structure type through comparative analysis of dense type,embedded type and dense embedded type.Based on the empirical formula,the best asphalt aggregate ratio is obtained by the test method of common asphalt mixture and the evaluation of local cold aggregate.In this paper,on the premise of Engineering grading,the best ratio of oil and stone and the ratio of powder and glue are determined,and the mixture is mixed for indoor test.Based on the evaluation of the three basic elements of the road performance of asphalt mixture,through the high temperature stability,water stability(freeze-thaw splitting test)and low temperature crack resistance road performance test of cold patching asphalt mixture,the paper analyzes the data and establishes the model to obtain the grading optimization model.Based on the grading optimization model,determine the ratio of asphalt to aggregate and the ratio of powder to binder,get the better performance of cold patch,and predict its road performance.From the perspective of practical application,this paper further explores the construction technology of cold patching materials,and expounds the construction details in detail.Based on the actual project and the actual test data,the practical application of this kind of cold patching asphalt mixture is feasible.