Geotechnical Investigations and Proposal for Stabilization and Recovery Slope on Highway BR-010 Stretch in Aparecida do Rio Negro to Goiatins, Tocantins, Brazil

摘要

This article presents the results of geotechnical studies and proposals to stabilize embankments referring to cuts 16, 23, 25, 30 and 31 of the BR-010 referring to Aparecida do Rio Negro a Goiatins, State of Tocantins. The study consisted in the execution of a field incursions program for verification of geotechnical conditions along the indicated stretch, running lab tests, and stability analysis of embankments in order to indicate solutions to cuts made necessary for the completion of the highway. In terms of characterization of the problem, it presents part of the photographic survey conducted in November 2007 with the conditions of the most critical slopes. There is in the pictures that the side slopes to the highway were in the process of degradation and (or) progressive destabilization requiring urgent interventions aimed at mitigating the ongoing problems. In terms of geometry, the slope had heights up to approximately 35 m. To determine the parameters necessary to verify the stability of embankments using three undeformed blocks corresponding soil to cuts 25 and 31. Samples of identifications are presented and the summary of the results of geotechnical tests performed and certain parameters. In laboratory tests, it was found that the strength parameters (cohesion and angle of friction) diverged somewhat from the usual laboratory parameters obtained in soils. This behavior was due to the fact that the heterogeneity of the samples for the presence mainly of discontinuities in the collected blocks. Before the run stability analysis and field surveys, it was found, the need for actions aimed at solving problems for marginal slope to the highway. Thus, due to the proximity of the intense rainy season, it was proposed the reconstruction of slope with surface protection of them aimed at stabilization and protection against erosion, as well as the execution of superficial and deep drainage. Aiming to further verify the possible degradation of the slopes by rain, was sought in INMET's website (National Institute of Meteorology) precipitation to the region. It was found that for the time in January, February and March rainfall is considerably high, which could further compromise the integrity of the executed cuts. Faced with this possibility, he indicated consider the emergency actions that could prevent this degradation. Actions such as the reduction and protection of embankments shown in the study.