Geotechnical Field Investigations to Measure Soil Resistances on the Contorno Oeste Highway in Boa Vista/RR and Solution to Landfills on Soft Soils (Atena Editora)

Abstract

Among other challenges, embankments on soft soils have been inspiring to geotechnical engineers, designers and executors, to seek challenging solutions. On this subject, Professor Márcio Almeida, one of the greatest experts on the subject, mentions that these challenges have already resulted in successes and memorable ruptures in works based on soft soils. In general, soft soils are considered, materials of high plasticity, in some cases rich in organic matter, with Nspt ≤ 4. Thus, brief considerations on soft soils are presented, but also results with analyzes and discussions of geotechnical studies carried out on the Highway West Contour of Boa Vista (BR 174), in the State of Roraima, aiming at the determination of soil resistance by means of in situ Palheta Tests (Vane Test), according to ABNT NBR 10905: 1989 (MB-3122). The studies consisted in the execution of “Geotechnical Field Investigations” in sections comprised by 11 piles of the aforementioned Highway. Considering the results, it was found that the soft soil layers in the studied sections have variable “average” thicknesses from section to section with minimums close to 2.0 meters and maximums that exceed 6.0 meters. Furthermore, the existing embankments of the old track, located in the studied sections, indicate the presence of soils of low bearing capacity under the body of the embankments. In addition to the studies, solutions are proposed for landfills on low bearing capacity soils.