Study On The Aggregate Anti Polishing Experienment In Chongqing Area

The pavement lacking of anti-sliding has been plagued builders among them, According to the past experience indicating that asphalt pavement anti-sliding performance falls fast with the using time growth,which is often below the standard requirement in four or five years. There are many factors which effect the anti-sliding performance of asphalt surface.But the most fundamental factor is raw materials.Terefore taking the basalt gravel, limestone gravel, broken pebble which are used in chongqing region to do the indoor polishing experiments. The experiments adopt the LR-T0321 accelerated polishing machine(19200r/h) and BM-Ⅲ pendulum friction tester to test. Through experiment study found that from the beginning to 150000 times the aggregate polished value decay quickly and the polishing value reached 43, 44, 37, except the limestone rubble, the others polished value is higher than the standard requirement 42. From 500000 to 700000 roles polishing value tends to be stable, the polishing value respectively reach to 28, 24, 26.Between 150000 to 500000 three kinds of aggregate polishing value decay slowly, and draw three kinds of rock polished value attenuation rate: basalt rock < broken pebble < limestone rubble. In addition through the correlation experiment about aggregate crushing value, abrasion and polishing, finding that there is collinearity roblems among the three indicators. Through using gradually delete method eliminate the abrasion value variable find that crushing value and polished value have good linear correlation. In the study of aggregate crushing value, obtaining that limestone gravel crushing value and the needle flake content has good linear correlation.In order to study the asphalt pavement anti-sliding performance attenuation rule which is effected by the aggregate polished value, choosing the AC-13 C as researching grading. Bailey method and density method are used to test the selected grading and it is concluded that the selected grading has good skeleton compactness. Using basalt gravel as coarse aggregate and limestone rubble as fine aggregate to make AC-13 C asphalt mixture and paving and compacting it in the test groove. Using the MMLS3 small acceleration loading tester to research the decay law of AC-13 C anti-sliding performance of asphalt mixture with wheel load increase under the condition of room temperature, 0.7 MPa tire pressure and axial load times to 7200 times/h. After 2 million times of wheel load using spss software to analyze data, it is concluded that asphalt road anti-sliding performance attenuation as same as aggregate polished value attenuation law which decay in the same form of logarithmic. And it shows that the aggregate anti-wear performance is a major factor which influences the asphalt pavement anti-sliding performance.