Avaliação de estabilização de solo para fins de base e sub-base na região de Urucu

Abstract

In road construction projects in the Amazon region, high logistical costs and the scarcity of stone aggregates make the use of local materials a strategic necessity. In the Urucu region (Coari-AM), this scenario is aggravated by the predominance of fine, expansive soils with low bearing capacity, which renders their direct use in pavement structures unfeasible. In this context, the present work aims to conduct a case study on the chemical and granulometric stabilization of these soils for use in base and sub-base layers. The methodology was based on the analysis of geotechnical reports containing characterization, compaction, and California Bearing Ratio (CBR) tests. The results for the soil in its natural state confirmed its structural unsuitability against the DNIT criteria. However, mixed stabilization through granulometric correction with sand and gravel, combined with the addition of low contents of Portland cement, promoted significant gains in mechanical strength. The stabilized mixtures reached CBR values of up to 85% for the sub-base layer and 143% for the base, in addition to drastically reducing expansion. It is concluded that the use of local soils through stabilization is a technically viable solution that fully complies with current standards, contributing to the development of infrastructure adapted to the logistical reality of the Amazon.