Abstract:
Given the paramount importance of soils in unsurfaced or thinly surfaced roads, it seems worthwhile to evaluate soils on the basis of both pavement and soil mechanics. Such a rational approach is used to discuss the mechanical behavior of a residual soil found in southern Brazil. The experimental program included tests traditionally used in pavement engineering, such as grain size distribution, Atterberg limits, compaction, California bearing ratio, resilient modulus, and permanent deformation under repeated loading. The influence of water content and compaction degree on soil strength and stiffness was quantified. In addition, direct shear tests were performed to define shear strength parameters that were used to verify layer safety against failure. Water retention curves, which relate soil suction to saturation degree, were used to analyze permanent deformation evolution under repeated loads. The interpretation of test results confirmed the suitability of the suggested approach for evaluating soils for low-volume road construction.
