Southern Mountain Highway Sma Mix Design And Road Performance

In southern mountains, there are many unfavorable environmental features, such as complicate topography, large precipitation, heavy fog, poor ability of sight and long term of high temperature and etc. It is put forward to resolve the problems of high traffic, serious surcharge and a lot of long scarps hi Jingzhu expressway aiming at environmental features.On the backgrounds of SMA researches inside and outside country, two importing 70# asphalt in Taiwan and Thailand are selected and modified by SBS on the spot. Furthermore the test projects of modified asphalt matrix are brought forward based on modified asphalt's technical indexes. By the tests, ductility and softening point of matrix of three kinds of fibers and different F (the ratio of filler to bituminous contents) are analyzed. Then the ranges of F suited to this area are found out.In this paper, coarse aggregate gradations are unproved by using Uniform Design method to insuring framework structure. Fine aggregate gradations are designed by k method hi principle of dense and filling. Then 19 kinds of SMA tentative gradations are designed by volumetric methods. At the same tune, effective bituminous contents are put forward. So 7 lands of SMA mixtures are selected by using the key volumetric indexes, VV, VFA, VCA, as controlling indexes. Moreover many important pavement performances and influencing factors such as high temperature stability, water stability and anti-slip performances are analyzed and researched scientifically and deliberately. What's more, anti-fatigue and low temperature anti-cracking performances are studied by tests too. Finally the optimal SMA gradation is recommended. Testing roads are laid down in order to probe the key technologies in operation.