Research On Influence Of Rock Character On Asphalt Mixture Volume Index

Considering the previous reports and the present study, the thesis analyzes and summarizes the general situation of the asphalt mixture volume index. According to the deficiency on volume index in China, the calculating method of asphalt mixture and the change law of volume index are particular studied.Firstly, the thesis studied determination method of relative density on most large theory. The effects of different relative density on most large theory to results of the asphalt mixture volume index are discussed. The advantages and disadvantages of various density measuring methods on asphalt mixture are discussed. It is concluded that the relative density on most large theory should be measured as far as possible, and it is suggested that the hairy volume densities of mixture specimens measuring by tables dry method.Then, in view of the basalt and the limestone, using 4 kinds of gradations, 5 kinds of oilstone ratios, and methods of the Marshall compaction and rotating compaction, the specimens are formed. And then compared with the change law of volume target, it is concluded as follows:(1) The change laws of basalt and the limestone volume target are similar. the gradation regulation blend's bulk volume relative density is bigger, the percentage of voids is smaller, the mineral aggregate gap rate is smaller, the asphalt degree of saturation is bigger; And along with oilstone compared to enlargement, the blend bulk volume relative density increases gradually, the percentage of voids reduces gradually, the asphalt degree of saturation increases gradually.(2) The Marshall design method is selected. As a result of the stone material difference, caused the same gradation and oilstone ratio, basalt blend test sample bulk volume relative density compared to limestone blend test sample bulk volume relative density average big 0.098; Percentage of voids average big 0.933%; Mineral aggregate gap rate average big 1.573%; Asphalt degree of saturation average small 3.091%.(3) For the basalt, the same gradation and oilstone ratio, the test sample which the revolving design obtains the test sample which obtains the Marshall design is denser than, the blend bulk volume density increases 0.067 slightly equally, the percentage of voids average 2.47%, mineral aggregate gap rate average small 2.22%, asphalt degree of saturation average big 10.67%. For the limestone, the revolving design obtains test sample the test sample which arrives the Marshall design is denser than, the blend bulk volume density increases 0.051 slightly equally, the percentage of voids average 1.98%, mineral aggregate gap rate average small 1.64%, asphalt degree of saturation average big 10.79%.