Research On Material Composition And Performance Of Asphalt Pavement SMA-13 In Guangxi

SMA is made up of coarse aggregate skeleton and asphalt mastic and its character is to have more asphalt binder,coarse aggregate,mineral powder and less fine aggregate,and mixed with fiber stabilizer.More coarse aggregate,which forms the skeleton structure,gives SMA an outstanding high temperature performance,fatigue resistance performance and so on,but its disadvantage is the high requirements for raw materials,in which basalt is usually chosen.And Guangxi region is rich in limestone with parts of the areas having a certain reserve of diabase,but basalt resource is limited.Therefore,combining with the local materials of Guangxi,studying the SMA asphalt pavement that is suitable for Guangxi is of great significance.This research is based on traffic science and technology project on technology research and application of the durability of asphalt pavement in Guangxi overhaul engineering and based on the engineering " pavement reconstruction project in Guangxi guilin to Liuzhou expressway(Liaotian to Luzhai North exchange)".The project uses the local limestone and diabase,and it is in a region that is of high temperature and rainy,along with a large traffic volume.Therefore,research on SMA-13 that is made from local limestone and diabase,is good to local conditions,effective utilization of resources and sustainable development,and can enhance the durability of pavement construction schedule,and economic benefits.This paper uses raw materials such as aggregate and asphalt from GuiLiu expressway engineering to do indoor test,measuring the basic properties of diabase and limestone,including density,crushing value,polishing value,abrasion value and so on,to explore whether they satisfy the requirements of SMA aggregate,and comparing them with basalt.This paper alse uses the hyperbolic model and the most compact design method to design SMA-13 mixture.Starting from the raw material composition and the basic properties,this paper mixes diabase and limestone by different blending ratio,which makes the mixed coarse aggregate SMA,limestone SMA and diabase SMA then measures the volume indexes and performance,analyses regularity of mixed coarse aggregate SMA,and compares them with basalt SMA.The experiment proves that under the optimum grading,limestone SMA-13 is of a bad index and performance;75%:25% limestone: diabase SMA-13 is similar with the limestone SMA-13;50%:50%limestone: diabase SMA-13 has a bad volume index but its performance is good and25%:75% limestone : diabase SMA-13 is of a good performance and volume index;Diabase SMA-13 is the best of them and can totally replace of basalt SMA.Though paving experiment road,this paper researches the construction technology and quality control of SMA-13 which is designed by the most compact design method,and at the same time the infrared thermal imager is used to monitor segregation and temperature of SMA-13 during the process of the construction.On-site inspection report indicates that the paving technique is in accord with the diabase SMA-13 and construction dissociation and temperature is well-controled.