BI-LOGARITHMIC CORRELATION EQUATION TO EVALUATE THE CBR WITH DCP INDEX OF QUARRY MATERIAL

Abstract

This article presents a bi-logarithmic correlation equation between CBR values and DCP Index values with the respective laboratory test results evaluated in the Soil Mechanics Laboratory of the Universidad Nacional de San Antonio Abad del Cusco, which allows the evaluation of in situ CBR of the subbase course of pavements, conformed with material from the Vicho quarry, during the construction process of road projects in the city of Cusco.

According to the coefficient of determination of R²= 95.91%, the bi-logarithmic correlation equation determined based on the CBR laboratory test results, evaluated on compacted specimens with certain percentages of the compaction energy considering the method C of the modified Proctor compaction test, and the DCP Index values evaluated on the same compacted specimens is appropriate for evaluating the value of in situ CBR of the Vicho quarry soil used to conform the subbase course in road pavements of Cusco city, using the reliably correlation equation.

The physical properties of the material from the Vicho quarry, to conform the subbase course of pavements, are: w = 5.67 %, LL = 23.74%, LP = 18.09%, PI = 5.65%; thus, the soil is type A-1-a(0) according to the AASHTO soil classification system. The results of the modified Proctor compaction test were: γ_d(max) = 21.87 KN/m³ and w_opt = 7.10 %.