Chemical stabilization of soil with addition of active silica and cement for use in road pavement layers

Abstract

According to the National Transport Confederation (CNT), in 2018, about 60% of Brazilian production was disposed of by road transportation. To provide quality transportation, these highways must meet minimum strength and drainage requirements that will provide greater safety and comfort to the user. However, local soil does not always have minimal geotechnical characteristics that meet design requirements. For Machado et al. (2003), the lack of soils that have characteristics required by road agencies, becomes a hindrance to the transportation sector in Brazil. To solve the problem of lack, there are some alternatives, among them: change of the characteristics of the work to suit the soil, soil change, or local soil stabilization. With regard to this last alternative, it consists of soil improvement through the addition of materials such as cement, lime, silica, among others. The present work presents the use of silica in comparison with the use of cement, for the stabilization of a low quality soil with 15% of active silica, as well as for cement, since it is a comparative study. . The characteristics analyzed that determine the improvement refer to the granulometry, plasticity, specific mass, optimum humidity, besides CBR to determine the resistance, along with the expansion. The results show that the use of silica contributes significantly to the stabilization, even in smaller percentages when compared to the use of cement. However, this is an alternative that can be analyzed according to the feasibility of use for the particularities of the work to which it is submitted.