Choice of aggregates for permeable pavements based on laboratory tests and DEM simulations

Abstract

Permeable pavement plays an important role in the sustainable urban drainage system as they have the potential to reduce splash and spray. While the pavements need to be permeable for the water to drain into the ground, it must also be able to carry the traffic load without altering the permeability characteristics. This paper aims to investigate the permeability performance and serviceability of pavements constructed with aggregates having a range of crushing strength (crushability) and grading (particle size distribution). Laboratory tests consist of modelling a pavement and carrying out permeability and sieving tests before and after the application of the loading. Experimental investigations showed that particles having higher crushing strength will lead a lower reduction in permeability of the pavement without compromising the performance. Furthermore, it was observed that reduction of permeability depends on the particle breakage pattern. Numerical study was conducted using discrete element modelling to understand the underlying mechanism of this phenomenon, and it was found that a wide particle size range could distribute the load uniformly and reduce the particle breakages. It is suggested that all these factors may be considered while choosing the aggregate for permeable pavement.

Keywords:

• permeable pavement
• aggregate
• particle breakage
• particle size distribution
• discrete element modelling

Acknowledgements

The authors would like to thank the project students, H.A. Hill, A.J. Sutherland and Stavros Kylakos for their contributions to different aspects in this paper. The authors would like to thank Sukalpa Biswas (Now Atkins, previously Mouchel) for providing the interesting problem to look into.

Disclosure statement

No potential conflict of interest was reported by the authors.