Study on Verification of Evaluation Indexes of Shear Resistance of Asphalt Mixtures Based on GTM Method
The high temperature performance of asphalt mixtures can’t be evaluated comprehensively by present widely-used rutting tests. In this paper uniaxial penetration test and GTM(Gyratory Testing Machine) method are adopted in order to test, evaluate and make correlation analysis of shear resistance performance of asphalt mixtures at high temperature. Combined with verification results of field investigation, this paper finds the shear strength in uniaxial penetration test at 60°C and index GSF in GTM method can objectively show the shear resistance performance of asphalt mixture at high temperature and can be used to test the high-temperature stability of asphalt mixtures. Besides, there is a good linear correlation between both and the correlation coefficient R is 0.9597. For the surface or medium layer of asphalt mixture in highways, the shear strength should be no less than 0.7MPa in the uniaxial penetration test at 60°C and the shear safety factor GSF shall be no less than 1.3 in GTM method.