Evaluating the effect of reinforcing fibres on pervious concrete volumetric and mechanical properties according to different compaction energies

Pervious concrete surface layers represent a construction material with many positive features. It is acknowledged as a useful tool to reduce water run-off and it provides environmental benefits by lowering the pavement surface temperature, noise due to traffic and pollutants. Unfortunately, high drainability properties do not comply with high resistance and durability when facing traffic conditions. Standards and rigorous specifications for construction and placement are lacking and contractors rely on experience to conduct the work. The same aggregate sieve distribution and paste content can result in different pervious concrete pavement characteristics depending on the compaction energy applied. Too much compaction will generally reduce voids while enhancing resistance and vice versa. The present study aimed at evaluating the improvements due to reinforcing fibres into pervious concrete mixtures for achieving better performance. In particular, void content, permeability, stiffness and tensile strength were evaluated according to several compaction energies and types of fibres. Results identified certain types of fibres as a potential improvement for pervious concrete mixtures increasing mechanical performance while maintaining the drainability features. The primary goal was to determine a correct balance in compaction to be provided and mechanical performance to be achieved, which would result in a proper resistance-to-drainability ratio.