Utilization of Coir Fibre Ash (CFA) in Cement Stabilized Peat

Abstract

Peat is a soil that has a high compressibility property beside having a low bearing capacity. Due to these problems, the peat soil is not suitable for construction purposes. Coconut waste is an example of agricultural waste. In the context of environmental sustainability, the use of coir in geotechnical applications is desirable. This research was conducted to study peat stabilization by using Coir Fibre Ash (CFA) in partially replacing Ordinary Portland Cement (OPC) to improve the physical and geotechnical characteristics. Geotechnical laboratory experiments involved in this study are moisture contents, organic contents, fiber content, Atterberg limits, specific gravity, Unconfined Compression Strength Test (UCS), Scanning Electron Microscope (SEM) and Energy Dispersive X-Ray (EDX). In this study, the use of CFA as a stabilizer were used at mixture ratio of 5, 10, 15 and 20% of OPC replacement. Based on the UCS test carried out, it is found that the optimum strength for each ratio of CFA in the mixture showed a decrement pattern if compared to cement stabilized peat (PC). The results of SEM test shows that the structure of untreated peat becomes denser after stabilized. This is due to the cementing process. EDX test shows that the carbon content in the soil decreases while calcium content increases after the stabilization process is executed. Therefore, CFA is suitable to be used as pozzolan material in stabilized peat and can reach up 200kPa of UCS at 20% OPC replacement.