This research project was conducted to investigate the ability of foamed asphalt to stabilize local marginal sand aggregates for useas base or subbase pavement materials. The variables measured were intended to give indications of the quality of performance of these mixtures as well as aid in the development of design procedures for the use of foamed asphalt as a stabilizing agent under the relatively high temperature conditions in the Arabian Gulf. Quantitative information is given about the effects on mixture response of significant factors such as sand type and gradation, quality and quantity of the fine fraction, asphalt grade and its percentage, moisture content, and curing condition. Both moisture and temperature susceptibilities of foamed-asphalt mixes were found to be significantly reduced bythe addition of limestone powder to modify the fine fraction of sand. Structural response of foamed-asphalt mixes was compared with that of other hot-asphalt-sand mixes commonly used as base material in Kuwait. It appears that properly designed foamed-asphalt-sand mixeshave a structural thickness that corresponds to that of hot asphaltand much less susceptibility to permanent deformations under traffic loads in hot environments.(A).
Abstract