Estudo de correlação entre os índices de DCP e CBR de solos típicos da cidade de Natal/RN

Abstract

To guarantee safety and functionality at any paving work, technological control throughout site and laboratory tests is an essential tool. In this context, the use of the Dynamic Cone Penetrometer (DCP) has gained popularity to estimate soil parameters, such as the California Bearing Ratio (CBR), through correlation studies. Therefore, this paper aimed to establish empirical relationships between CBR and DCP indexes of typical soils from Natal/RN, in the Brazilian Northeast. The necessity of this research originates from the lack of related studies and their increasing demand due to recent paving works. Two samples of soils from the northern and western regions of the city were collected and analyzed in laboratory. After an initial characterization, results were correlated from approximately 80 tests, performed at both soils at two compactive efforts and various moisture contents in-mold, submitted or not to immersion conditions. According to the characterization tests, the soil from the northern region was classified as silty sand (SM), and the western area as well-graded silty sand (SM-SW); both specimens assumed the A-2-4 highway classification. The obtainment of coefficients of determination (R²) higher than 0.90 in 75% of the developed correlations characterizes the applicability of DCP as a valid field-testing instrument for technological control of local paving works, once it is a simple, fast and low-cost test. The findings of this study represent an advance in the definition and standardization of a simple, efficient, and safe methodology to the estimate of empirical correlations among these two soil parameters.