ESTABILIZAÇÃO DE SOLO COM CAL EM OBRA DE ESGOTAMENTO SANITÁRIO – ESTUDO DE CASO

Abstract

Linear works, such as the implementation of sanitary sewage collection networks, are characterized by the large movement of earth during their execution. Thus, the reuse of soil in the backfill stage is a practice to be performed, whenever the geotechnical characteristics of the excavated material allow its reuse. When this does not apply, the use of material from the deposit is carried out, which leads to an increase in expenses arising from the disposal of material, transport of the new input to the construction site and/or service front, its purchase cost, among other values involved in its logistics. Soil improvement with the use of lime emerges as a possible effective, economic and sustainable solution to this issue. The present article studies the incorporation of lime in the soil aiming at its stabilization for composition in the sub-base of the backfill of the trenches. The analyzed soil came from the excavation of the Sewage Collector Network (RCE) works of the Sanitary Sewage System (SES) of Cabo de Santo Agostinho. In this study, at first, the mechanical characteristics of the soil were analyzed through a simulation in which the incorporation of 1%, 2% and 3% of lime was carried out in samples collected in stretch 146 of Basin E1. After analyzing the results, an optimal percentage

was defined in order to adopt it in the stabilization of the other CER stretches. For this, the soil- lime mixture was carried out using this optimal percentage in 3 samples from the construction

site, where the soils that came from different sections were stored. It was verified that the normative mechanical properties were met, making it possible for the processed material to form the sub-base layer of the backfill. In addition to meeting the resistance of the soil, this improvement contributed to the reduction of costs in the work and working towards sustainability.