Estudo do efeito combinado da estrutura e da sucção sobre o comportamento mecânico de solos não saturados

• Ano de defesa: 2009
• Autor(a) principal: Custódio, Gisele Santos
• Orientador(a): Silva, Cláudio Henrique de Carvalho
• Banca de defesa: Marangon, Márcio , Marques, Geraldo Luciano de Oliveira
• Tipo de documento: Tese
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de Viçosa
• Programa de Pós-Graduação: Doutorado em Engenharia Civil
• Departamento: Geotecnia
• País: BR
• Palavras-chave em Português: Solos não saturados; Mecânica dos solos; Ensaios de laboratório
• Palavras-chave em Inglês: Unsaturated soils; Soil mechanics; Laboratory tests
• Área do conhecimento CNPq: CNPQ::ENGENHARIAS::ENGENHARIA CIVIL::GEOTECNICA
• Link de acesso: http://locus.ufv.br/handle/123456789/818

This work refers to study the combined effect of the structure and suction on the mechanical behavior of two soils in the unsaturated state, a predominantly sandy clay and others. The test samples were reconstructed with cement contents ranging from 0 to 4%. We performed the tests of physical-chemical, mineralogical soil without mixing, the micromorphological analysis, testing of incremental densification edometer sample under different test undisturbed trajectories of wetting and reconstituted with the contents of Portland cement in the percentages above, test of triaxial drained dense saturated characteristic curve of water retention in soil compaction with suction and controlled deformation and triaxial with suction and deformation controlled. To implement the latter has developed the project and subsequent construction of a triaxial cell with controlled suction. As findings are that: (i) the steps of applying suction and compression, the test CRSS apparently decrease the porosity of clay soil, (ii) the addition of cement causes a change in soil structure and reduced porosity, (iii) the strain of pre-compaction and flow at low voltages applied is increasing, most of the time, with increasing percentage of cement for the two soils, (iv) the size and amount of cement affect the behavior of compression and collapse of soils-test (v) the soils-proof clay soil with cement percentages of 0 and 1 and 2% to 3% tend to stress the pre-consolidation increasing, but very close; (vi) the natural samples of predominantly clay soil and sandy Collapsibles and are expandable under flooding, high and low voltages applied, respectively, (vii) the compression index increased with increasing suction, except in cases there have been the presence of flow at low voltages applied, (viii) sample of the two test soils have a behavior bimoldal, (ix) the flow in the compression curve is probably due to breaking the links between household- caused the compression and consequent saturation of the macropores of soils-proof restored; (x) for different strains of confinement, cementation increases the cohesion and does not change the angle of friction; (xi) the values of friction angle of soils-test samples in triaxial cell with controlled suction are smaller than those presented by the samples without suction, (xii) a triaxial cell with controlled suction performance was adequate, allowing the testing triaxial tests with controlled suction.