Assessing the recycling potential of glass fibre reinforced plastic waste in concrete and cement composites

At present glass fibre reinforced plastic (GRP) waste recycling worldwide is very limited due to its intrinsic thermoset properties, lack of characterisation data and non availability of viable recycling and recovery routes. In the present study, efforts were made to recycle GRP waste powder and fibre in concrete and cement composites and assess its quality to comply with the British standards for use in construction applications. Results revealed that the mean compressive strength of concrete composites using 5%–50% GRP waste powder under water curing varied from 37 N/mm2 to 19 N/mm2. Increase in the concentration of GRP waste decreased the compressive strength. However, increase in curing duration (14–180 days) resulted in improving the compressive strength of concrete with 5% GRP application to 45.75 N/mm2. Moreover, the density of concrete with 50% GRP waste was reduced by about 12% as compared to the control sample. The bending strength in terms of modules of rupture (MOR) of 12 mm thickness cement composites developed using 5% GRP waste fibre attained 16.5 N/mm2. The findings of this work pave the way for further GRP waste recycling in precast construction products for use in various applications.