(1) Research Scholar, School of Engineering, CUSAT, Cochin-22,

(2) Department of Civil Engineering, N S S College of Engineering, Palakkad-08,

(3) Department of Civil Engineering, School of Engineering, CUSAT, Cochin-22


This paper highlights the results of an experimental investigation, on the compressive strength behaviour of plastic fibre reinforced soil, undertaken to study the possibility of using waste plastics in soil masonry blocks. Cylinderical specimens of raw soil and modified soil compacted at different pressures by varying the moulding load from 10kN to 60kN were tested for compressive strength and density. Raw soil was modified by adding varying percentages of stabiliser (cement : 7.5% and 10%), fibre type (formed from either mineral water bottles or carrier bags), fibre length (1cm and 2cm) and fibre percentage (0.1% and 0.2%). The results show that, compared to raw soil specimens, there was an increase of between 16% to 28% and 26% to 48% in strength at low and high moulding pressure when the soil was stabilised by 7.5% and 10% of cement respectively. The stabilised and reinforced soil specimens showed strength values of 3.5-4.34MPa, which are satisfactory when compared to that of the minimum compressive strength of 3.5MPa specified for a well burnt brick in accordance with BIS 1077-1992 and the minimum compressive strength of soil blocks for general building construction in accordance with BIS:1725 – 1982.