Correlation Analysis of Laboratory CBR Values and DCP Tests on Coarse-grained soil

¹ Civil Engineering Department, Faculty of Engineering, Diponegoro University, Jl. Prof Soedarto, Tembalang, 50275, Semarang, Indonesia
² Tokyo Electric Power Services Co. Ltd (TEPSCO), Japan

^* Corresponding author: undayanicita@live.undip.ac.id

Abstract

Soil bearing capacity is crucial in infrastructure construction planning. Common testing methods used for evaluation are the Dynamic Cone Penetrometer (DCP) and the California Bearing Ratio (CBR). Numerous studies have examined the correlation between these two tests, but specific studies on specific soils are lacking. Furthermore, studies generally involve taking soil samples and then compacting them in a CBR mould. As a result, studies rarely employ compacted soil samples from the field. This study analyzes the correlation between CBR values based undisturbed sample and field testing using the DCP. The study was conducted on coarse-grained soil. The case study was located at the Batang Multipurpose Terminal (TMB), Batang Integrated Industrial Zone. The results showed that there were 6 from 9 DCP test points that had similarities. The highest deviation in this study occurred because the DCP testing position was located far from the undisturbed sampling point. Meanwhile, the lowest deviation was 0.25% for 0.1-inch and 3.14% for 0.2-inch penetration (less than 5%). This study also produced an equation from a regression model based on the relationship between DCP and CBR values for coarse-grained soil. This equation has correlation of 0.9471, which indicates a strong relationship between the two variables analyzed.