CORRELATION BETWEEN CALIFORNIA BEARING RATIO (CBR) AND DYNAMIC CONE PENETRATION ON A SOILS (CASE STUDY OF ARBAMINCH TO CHENCHA ROAD)

Abstract

There is lack of correlation between Dynamic Cone Penetration Index (DCPI) and Soaked as well as Unsoaked California Bearing Ratio (CBR) for local subgrade materials. The aim of this study is to develop relationships between DCP and soaked CBR, DCP and unsoaked CBR, soaked CBR and unsoaked CBR for a soil in particular on the selected road route. This paper presents relationships between DCP and CBR for local Subgrade materials. The relationship developed in this research considers subgrade material’s behavior and largely saves time and cost of preliminary and detailed engineering works of road projects. A series of DCP tests in the field, soaked CBR at OMC, and unsoaked CBR at field conditions in the laboratory are conducted. Based on the field and laboratory test results relationships between soaked CBR and DCP, unsoaked CBR and DCP, and soaked CBR and unsoaked CBR are established for soils on Arbaminch-Chencha road route. The relationship developed between DCP and soaked CBR value shows better than that of unsoaked CBR.