Civil Engineering Journal
Vol 4, No 11 (2018): November

Evaluation of the Performance of Reinforced Red Coffee Soils Embankments Subject to Rainfall Event

Salim Ali Zimbu (Pan African University Institute for Basic Science, Technology and Innovation (PAUISTI) hosted at Jomo Kenyatta University of Agriculture and Technology (JKUAT). P.O. Box 62000-00200 Nairobi, Kenya)
Joseph Thuo (Department of Civil Engineering, Dedan Kimathi University of Technology (DeKUT). P.O. Box 657-10100 Nyeri, Kenya.)
Nathaniel Ambassah (Department of Civil Engineering, Jomo Kenyatta University of Agriculture and Technology (JKUAT). P.O. Box 62000-00200 Nairobi, Kenya.)



Article Info

Publish Date
29 Nov 2018

Abstract

Infrastructure development in Kenya has led to the need for alternative material in slopes and embankments construction. Sourcing of recommended cohesionless material often leads to the destruction of the environmental features such as rivers and involves high extraction and transportation costs. The need for alternative material is the motivation behind this study. The study aims to evaluate the potential of Red coffee soils of Kenya as a backfill material in the construction of slopes and embankments. Provision of sand cushion layers to sandwich non-woven geotextile material has been suggested to overcome the water drainage and stability problems that have been associated with these soils. The study first involved identifying the properties of both the Red coffee soils (RCS) and the river sand that is to aid in drainage. Numerical model SEEP/W was used in evaluating the effect of geotextile inclination on the performance of RCS embankments before the effect of introducing sand cushions of different thickness evaluated. The numerical results revealed that the stability of reinforced RCS decreased with increase in pore water pressure in the embankments due to rainfall infiltration. Provision of sand cushion layers helped improve both the local and global stabilities of the RCS subjected to rainfall infiltration. The results showed that 150mm sand cushion layer was adequate to improve the performance of RCS embankments and reduced the sand consumption in the construction of embankments to 15%.

Copyrights © 2018






Journal Info

Abbrev

cej

Publisher

Subject

Civil Engineering, Building, Construction & Architecture

Description

Civil Engineering Journal is a multidisciplinary, an open-access, internationally double-blind peer -reviewed journal concerned with all aspects of civil engineering, which include but are not necessarily restricted to: Building Materials and Structures, Coastal and Harbor Engineering, ...