Rheology of fresh cement asphalt emulsion pastes

The rheology of fresh CA pastes of different asphalt emulsion to cement mass ratio (AE/C) with different particle volume fraction was studied. A modified Herschel-Bulkley model was proposed to fit the flow curve of CA pastes and calculate the yield stress and special viscosity (minimum apparent viscosity) of CA pastes. According to the fitted viscosities and yield stresses, a viscosity model was employed to establish the relationship between viscosity and particle volume fraction of CA pastes, and a yield stress model was employed to study the relationship between yield stress and particle volume fraction of CA pastes. Based on the two relations, maximum particle packing density of CA pastes was calculated and the relation between yield stress and viscosity was established to study the rheology of grouting CA pastes. Results indicate CA pastes with different AE/C have significant different relation of viscosity with particle volume fraction and relation of yield stress with particle volume fraction. In the condition of the same viscosity, the yield stress of CA pastes decreases quickly with the increasing AE/C from 0 to 0.4, and then increases slightly with AE/C from 0.4 to 1.0. The yield stress of CA pastes is very low and should be improved for grouting. These works can well reveal the rheology of CA pastes. (C) 2015 Elsevier Ltd. All rights reserved.