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Título: SETTLEMENT ANALYSIS OF AN EMBANKMENT ON VERY SOFT SOIL IN BARRA DA TIJUCA
Autor: CHRISTIANO FARIA TEIXEIRA
Colaborador(es): SERGIO AUGUSTO BARRETO DA FONTOURA - Orientador
SANDRO SALVADOR SANDRONI - Coorientador
Catalogação: 19/MAR/2013 Língua(s): PORTUGUESE - BRAZIL
Tipo: TEXT Subtipo: THESIS
Notas: [pt] Todos os dados constantes dos documentos são de inteira responsabilidade de seus autores. Os dados utilizados nas descrições dos documentos estão em conformidade com os sistemas da administração da PUC-Rio.
[en] All data contained in the documents are the sole responsibility of the authors. The data used in the descriptions of the documents are in conformity with the systems of the administration of PUC-Rio.
Referência(s): [pt] https://www.maxwell.vrac.puc-rio.br/projetosEspeciais/ETDs/consultas/conteudo.php?strSecao=resultado&nrSeq=21333&idi=1
[en] https://www.maxwell.vrac.puc-rio.br/projetosEspeciais/ETDs/consultas/conteudo.php?strSecao=resultado&nrSeq=21333&idi=2
DOI: https://doi.org/10.17771/PUCRio.acad.21333
Resumo:
This work presents a settlement analysis of an embankment built on a very soft soil deposit in Barra da Tijuca (Baixada de Jacarepaguá), which is located in Rio de Janeiro’s coast. The geotechnical profile shows a very soft soil with thickness reaching 17 m, with Nspt equal 0. The embankment was built in stages and its settlements were accelerated with prefabricated drains. The construction lasted about 1,5 year and was monitored by means geotechnical instrumentation. Field and laboratory test programs were carried out to define the geotechnical characteristics of the soil. Ten samples were collected from two vertical boreholes before any loading was applied to the soil. To avoid disturbance, each stage of sample process, from sampling to specimen preparation, was conducted with special procedures. Tests have been carried out both in undisturbed (vertical and horizontal directions) and completely disturbed conditions. The specimen preparation procedures are described in detail. Conclusions considered only the results of tests conducted on specimens with excellent quality. The in-situ tests were performed in vertical boreholes next to boreholes where the undisturbed samples were collected and in the same location in which geotechnical instruments group were installed. The analysis of the field and laboratory tests and instrumentation data revealed the existence of two very soft soil layers exhibiting distinct characteristics which are separated by a continuous sand lens. The upper soil layer (from surface down to about 5 m depth), that was probably formed after an unloading geological period of the underlying layer, is characterized by low effective in situ stresses. The underlying soil is also under low in-situ effective stresses, but with a preconsolidation pressure characterized by the difference s’p - s’v0 25 kPa (constant with depth). A correlation between OCR (from consolidation tests) and Su/sv0 ratio (from vane and CPTU tests) for similar soils has been updated. The high compressibility of soils was confirmed by the embankment instrumentation data. Ca/Cc values, higher than usual for most known soils, were found. Practical relationships have been updated to describe the permeability of the deposit. Soil consolidation coefficients were estimated in different ways and values, even though have showed large difference (up to ten times), did not showed tendency when laboratory or field (tests and instrumentation data) values were compared. Disturbance affected the permeability and compressibility (primary and secondary) characteristic of the soils of both layers, but its effects were more severe in the underlying layer. A numerical prediction, in which a creep-soft-soil model was used and parameters obtained from the laboratory tests were considered, lightly overestimated the embankment settlements with time.
Descrição: Arquivo:   
COVER, ACKNOWLEDGEMENTS, RESUMO, ABSTRACT, SUMMARY AND LISTS PDF    
CHAPTER 1 PDF    
CHAPTER 2 PDF    
CHAPTER 3 PDF    
CHAPTER 4 PDF    
CHAPTER 5 PDF    
CHAPTER 6 PDF    
CHAPTER 7 PDF    
CHAPTER 8 PDF    
CHAPTER 9 PDF    
REFERENCES PDF