Analysis of the resilience modulus of a subgrade soil front of humidity variations

Abstract

The influence of the variation of moisture content in the materials that make up the pavement has a negative impact on its performance. This variation in humidity is caused by inefficient drainage, oscillation of the water table, infiltrations, which affect the resistance and increase the deformability. The objective of this article is to evaluate the effect of moisture variation on the behavior of soils used in pavement subgrade from tests of resilience module. The subgrade of the highway BR-290/RS located in the state of Rio Grande do Sul/Brazil was evaluated. The repeated load triaxial equipment was used to perform tests of the Resilience Module (MR), varying the moisture content of the specimens by ± 2% in relation to the optimum humidity. There was a 70% decrease in MR comparing specimens above the optimum humidity with the ideal humidity conditions. A new MR equation was proposed that considers the variation in humidity, which showed high statistical significance. The results presented showed a great influence of the moisture content in soils, showing that the present article can contribute to a better understanding of the behavior of soils and a greater discussion about the effect of moisture variation in the dimensioning of pavements.