Zero Shear Viscosity Analysis of High Modulus Modified Asphalt

Zero-shear viscosity (ZSV) is an evaluation index for viscosity of asphalt to permanent deformation at high temperature. To investigate the applicability and influence of different test methods and calculation models on ZSV fitting for high modulus modified asphalt, and to promote the application of high modulus modifiers in road engineering, dynamic shear rheometer was used to perform 60 ℃ frequency sweep test and 60 ℃ steady flow test on base asphalt (BA) and high modulus modified asphalt (K1-HMB) with different modifier content. ZSV of test materials was fitted by Cross rheological model and Carreau rheological model. Finally, grey correlation analysis was used to further explore the degree of correlation between ZSV and softening point. The results show that BA and K1-HMB are pseudo-plastic fluids and both exhibited shear thinning characteristics under loading frequency. K1-HMB with 0.6% content had the highest elastic recovery capacity, and the recommended content of K1-HM modifiers was 0.4%～0.6%. The ZSV fitting value based on the 60 ℃ frequency sweep test combined with Cross model had the highest reliability and could be used as an evaluation index of the high temperature performance of high modulus modified asphalt.