STABILISATION OF SOIL BY NAOH AND SISAL FIBRE: AN EXPERIMENTAL STUDY

Abstract

Stabilisation is a process that is often used to enhance the engineering features that soft soils (clay soils or cohesive soils) typically display. These attributes include low strength, swelling and shrinkage characteristics, etc., and the most frequent way that these properties are improved is by stabilisation. In this study, an effort was made to determine whether or not soft soil that had been mixed with an alkaline solution was efficient in stabilising soil. It not only offers a solution for the correct utilisation of alkaline solution but also offers a substance that makes an excellent subgrade for the building of pavement.The use of natural fibre in civil engineering to improve the qualities of the soil is favourable since natural fibres are inexpensive, readily accessible in the area, and kind to the environment. Shear strength, load bearing capacity, and other engineering features of the soil all see considerable improvements as a result of the natural fibre reinforcement. The usage of naturally occurring, artificially created, and synthetically produced fibre in a random distribution has seen a significant rise during the last ten years. With this in mind, an experimental investigation was carried out using the soil that was readily accessible in the area, which had Sisal fibre added to it. In this particular investigation, the soil samples were produced in the CBR mould at their maximum dry density, which corresponded to their optimal moisture content. The mould was either reinforced or left unreinforced. It was determined that the ideal level of sisal fibre content in the soil included 0.2 percent, 0.4 percent, 0.6 percent, 0.8 percent, 1.0 percent, 1.2 percent, 1.4 percent, 1.6 percent, 1.8 percent, 2.0 percent, 3.0 percent, 4.5 percent, and 7 percent respectively. In the current investigation, the length of the fibre was determined to be 30 millimetres. The results of the testing helped inform the decision to go with this length. The laboratory CBR values of soil that had been reinforced with sisal fibre and a chemical compound at various percentages were measured, and the effects of the proportion of fibre and chemical on the CBR value, UCC value, and shear value of the soil were also explored. Sisal fibre is a substance that may be broken down by natural processes. Therefore, in order to increase its longevity, it is required to apply an agent such as turpentine oil or linseed oil. Both of these oils have similar effects.In conclusion, this study provides a notation on the optimal percentage of fibre and Chemical compound to achieve the good results. It also provides a comparison between normal soil, reinforced soil, chemically stabilised soil, and chemically stabilised and reinforced soil. Additionally, it provides a brief information of the behaviour of stress in soil both before and after the addition of the chemical and fibre.