Results are described of a research effort on the epoxy-based treatment of fine, poorly graded soil found at some localized low-dutyairport sites and in the north slopes of alaska. Statistical modelsare developed for the stabilization of clay-silt pavement systems at low-duty airports. A nontraditional method of soil stabilization that improves the subgrade strength properties of poorly graded clay-silt was identified. This soil system is considered one of the most difficult soil types to stabilize, in part because of its poor particle size distribution. Among several organic additives tested, the two-part epoxy system--bisphenol a/epichlorohydrin resin plus a polyamide hardener--gave the best result as measured by the dry california bearing ratio (cbr) test. The choice of the dry cbr test performedto astm specification was motivated by a need to capture optimum moisture content as an experimental variable. Within the limits of thelaboratory test conditions, the statistical regression models developed support the hypothesis that the marginal increase in cbr valuescaused by a 1% increase in epoxy resin application is 11.1 And the marginal degradation of cbr caused by a 1% increase in moisture level in -5.6. Also, only additive level, moisture content, and temperature are significant variables influencing soil strength. This paper appears in transportation research record no. 1295, Soil stabilization 1991 .
Abstract