TITLE:
Comparing the Casagrande and the Fall Cone Penetrometer Devices using Lateritic Soils Developed on Different Parent Rocks
AUTHORS:
Reine Carine Mafo Wambo, Valentine Yato Katte, Moses Chrimbana, Bertille Ilalie Manefouet Kentsa, Maurice Kwekam
KEYWORDS:
Dschang, Lateritic Soil, Casagrande Apparatus, Liquid Limit, Fall Cone, Soil Classification
JOURNAL NAME:
Journal of Geoscience and Environment Protection,
Vol.13 No.9,
September
30,
2025
ABSTRACT: A comparison between the Casagrande cup method and the Fall cone penetrometer devices for determining the liquid limit (LL) was conducted on lateritic soils developed on basalt, granite, and gneiss in the northeast area of Dschang city. The goal was to identify which device provides more reliable results. A total of 133 soil samples were collected and tested using both methods. Additionally, nine representative samples from each parent rock type underwent geotechnical analysis. The granulometric analysis combined with the Atterberg limits enabled soil classification for each substrate. Soils on basalt and gneiss are classified as high plasticity clays, while those on granite are low plasticity clays. Data were analyzed using Microsoft Excel and SPSS version 26. The findings indicated that the Fall cone device produced more accurate results than the Casagrande apparatus, although the difference was not statistically significant. A correlation analysis showed a strong positive relationship between the two methods for soils on basalt, expressed as: LLc = 0.78 LLp + 16.50, with an R² of 0.60. The correlation was moderate (R² = 0.4) for soils on granite and weak (R² = 0.1) for soils on gneiss. This relationship should not be generalized to specific soil types, as it is affected by soil plasticity and device configuration.