Mechanical properties of pressure moulded fibre reinforced pervious concrete pavement brick

Abstract

Utilising pervious concrete (PC) increases the environmental, economic and social benefits. This study aims to investigate the mechanical performance of PC paving bricks using smaller single-sized coarse aggregates with different types of fibres: Kevlar, Polyvinyl Alcohol (PVA) and Ultra-High Molecular Weight Polyethylene (UHMWPE) fibres. Four PC mixes were designed using a modified ACI method and paving bricks formed using a pressure compaction method of 2 MPa and air-curing for 28 days. Results showed that the use of smaller coarse aggregate results in reduced porosity. However, the addition of fibres at a volume fraction of 0.3 % lead to approximately 47 %, 21.5 % and 18.8 % decrease in 28-days compressive strength, and 26 %, 7.3 %, and 17.6 % reduction in tensile splitting strength for specimens containing Kevlar, PVA, and UHMWPE fibres, respectively. When compared with the control group, an optimum 9.5 % increase in the flexural strength shows the effectiveness of the fibre addition. The permeability values range between 0.15 cm/s to 0.39 cm/s, which is proportional to the porosity of the material and satisfactory according to ACI standards. Combining the pressure compaction method and the addition of fibres adversely affects the compressive and splitting tensile strength, while increasing the flexural strength slightly. An alternative forming/moulding method that can fully utilise the addition of fibres is worth further investigation.