UC Pavement Research Center, Sustainable Transportation Center
Available online at doi: 10.1061/ASCEMT.1943-5533.0000009
Fu, Pengcheng, David Jones, John T. Harvey, Felipe A. Halles (2010) Investigation of the Curing Mechanism of Foamed Asphalt Mixes Based on Micromechanics Principles. Journal of Materials in Civil Engineering 22 (1), 29 - 38
This study investigated the curing mechanism of foamed asphalt mixes. Various laboratory strength and stiffness tests were performed on mixes with various asphalt and portland cement contents, and the specimens were subjected to two relatively extreme curing conditions. It was found that portland cement enhances certain properties of foamed asphalt mixes by strengthening the mineral filler phase, with the curing mechanism similar to that of typical cement treated materials. The curing mechanism of foamed asphalt mastic is primarily related to water evaporation. The bonding between asphalt mastic and aggregate particles cannot fully develop until most of the water retained at the interface evaporates. This bonding, once formed, is only partially damaged by reintroduced water. This proposed mechanism was supported by observations of fracture faces on tested specimens. A long-term curing study confirmed the validity of this mechanism regardless of the curing duration. Standard curing procedures are proposed for use in project level mix design and evaluation based on the findings.
Keywords: foamed asphalt, pavement rehabilitation, curing, image analysis, micromechanics, full depth reclamation