Diagnóstico e proposta de solução para obra de canal assente em solo expansivo da região de Propriá/SE

Abstract

Expansive soils are unstable materials in which changes in moisture cause expansion if the moisture content increases and contraction with drying. The triggering of these phenomena depends on internal and external mechanisms, including contact with water and forces of an expansive nature originated in clay minerals. The geotechnical investigation on unsaturated soils is necessary in order to avoid damage to the structures built on them and expenses in remedial measures. The diagnosis involves evaluating the expansion through physical, mineralogy, microstructural and chemical characterizations of the soil. The present research aimed to physically characterize and propose a solution for the soil that is under the irrigation channels of the study region 02 of the Cotinguiba-Pindoba system located in Propriá/SE, in view of the pathologies found in the channels, which demand constant rehabilitation by the Companhia de Desenvolvimento dos Vales do São Francisco e Parnaíba (CODEVASF). Four undisturbed samples were collected in the stretch chosen for the research for geotechnical characterization and expansion tests. The diagnosis made based on the test results and the criteria in the technical literature indicated soils with high to very high expansion, which offer a risk of demolition of concrete structures. The analyzes carried out culminated in the indication of three possible solutions to combat the observed pathologies.