Cell K0-UFBa, a proposal for obtaining K0 parameter in laboratory
DOI:
https://doi.org/10.14195/2184-8394_154_3Keywords:
Earth pressure at rest, Laboratory test, Residual soilAbstract
The present work introduces the K0-UFBa cell, which has been shown to be an efficient device for determination of the coefficient of earth pressure at rest of soil from undisturbed samples. The K0-UFBa cell was developed and licensed at LabGeo at the Polytechnic School of the Federal University of Bahia (UFBa), Brazil. Its main components and assembly details are shown. The development of the equipment was based on the odometer tests with lateral confinement of water, which as incompressible, does not allow deformation in this direction, maintaining the K0 condition. In order to evaluate the results of the K0 cell on undisturbed samples obtained from two wells in residual soil, these results were compared with DMT tests, which were done next to the wells. The results showed similar behavior along the depth at both test areas when compared with K0 cell results and field tests (DMT). The small variation in the values is mainly due to the heterogeneity of the residual soil, associated to factors such as surface erosion, cementation due to the presence of oxides and history of stresses originating from the mother rock.
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