PREDICTING SUBGRADE STIFFNESS OF NANOSTRUCTURED PALM BUNCH ASH STABILIZED LATERITIC SOIL FOR TRANSPORT GEOTECHNICS PURPOSES

Kennedy Chibuzor Onyelowe ； Duc Bui Van

《Journal of GeoEngineering》 13卷2期 (2018/06) Pp. 59-67

https://doi.org/10.6310/jog.201806_13(2).2

摘要

Predicting the subgrade stiffness of the nanostructured palm bunch ash stabilized lateritic soil for transport geotechnics purposes was successfully carried out on the A-2-7 lateritic soil according to AASHTO classification. The preliminary laboratory examination showed that the soil had high swelling potentials, medium expansion properties and highly plastic. For these reasons, the soil was stabilized with 5%OPC + 0% - 15% NPBA. The results showed that the admixture improved the strength properties of the stabilized soil remarkably. The results of the stabilization exercise were used to formulate a nonlinear multiple regression relationship for the stabilization variables which was eventually solved and correlated with the analytical expression of the subgrade stiffness according to Powell et al. (1984). The results of the prediction operation showed that the predicted subgrade stiffness possessed a better correlation than the analytical values and will yield better results when applied in the design and monitoring of the performance of the transportation infrastructures and pavement behaviour because of its robust features.

關鍵字

Subgrade stiffness ； transport geotechnics ； nanostructured palm bunch ash ； soil stabilization ； California bearing ratio ； moisture condition value