Análise numérica de solos não saturados colapsíveis: aplicação em uma pequena barragem de terra experimental

Abstract

This article presents a numerical analysis of collapsible unsaturated soils, used in a small earth dam located in the city of Quixadá, State of Ceará, Brazil. The collapsible structure resulted from the application of low compaction energy and low moisture content. Results of characterization, compaction and double consolidation tests for the borrowed material employed in the construction of the small dam are presented, aiming to identify the analysed samples and study the collapse phenomenon. With the test results, a numerical analysis of flow and balance was performed, using the software Slide 6.0 and UNSTRUCT, in an associated way, to predict the stress versus strain behaviour (collapse) of the experimental dam. The dam cross section has a core with soil compacted at optimum moisture content with standard Proctor energy, and shells in the dry branch. The goal is to verify the efficiency of a dam built with reductions in costs (due to less earthworks) and in water consumption, making it an important constructive solution for small dams in semi-arid regions. The experimental and numerical studies of the work with these characteristics pointed to stability conditions, considering that the dam did not failure during the monitoring season.