Ensaios triaxiais dinâmicos de um solo arenoso

Abstract

Dynamic triaxial (or repeated load) tests were performed with a fine sandy soil, residual material of sandstone, used in a sub-base layer of a flexible pavement in the State of Rio Grande do Sul, in order to determine its resilient modulus. The procedures for setting up the testing equipment, calibrating and using it, are described. A compressed air system for applying axial loads and confining pressure, LVDT's transducers, and an oscillograph were used. Soil specimens were tested at different points of a compaction curve, varying degrees of saturation, confining pressures and deviator stresses, frequencies and duration of deviator stress. Some conventional triaxial tests, unconsolidated undrained, and CBR test were made in order to seek possible correlations of resilient modulus with other parameters, such as deformation modulus and CBR. Also presented a few results of dynamic tests with pore-pressure measurements. Triaxial test results were used as input of the automatic program FEPAVE for the evaluation of how much elastic or resilient deformation of the pavement could be attributed to the resilient characteristics of the fine sandy soil. Cornments are made concerning this approach in Pavement Mechanics studies for simulation of structural behaviour not considered in present method of pavement design.