Suitability of rubberised oil palm shell layers to stabilise concrete block pavement systems

ABSTRACT

This study focuses on evaluating the response of concrete block pavement (CBP) reinforced with rubberised oil palm shell (ROPS) layers when subjected to vehicular loads using laboratory experiments and finite element (FE) simulations. The key parameters considered in this study are the sand bed thickness, oil palm content in ROPS layers, embedment depth of ROPS layers, and vehicle velocity. The dynamic loads due to the vehicular movement were generated using a real-time road unevenness signal. Outcomes from the lab-scale 1g experiments and FE simulations were expressed as displacement and acceleration responses in the frequency domain. CBP sections with sand bed thicknesses of 10mm and 70mm were found to yield high surface deflection and acceleration values, both with and without ROPS reinforcements. CBPs reinforced with the ROPS layer having 20% OPS content demonstrate the best performance compared to ROPS layers made with 5% and 10% OPS contents. Further simulations show that the ROPS layers at an optimum embedment depth of 180mm from the surface in the CBP profile can significantly reduce the unacceptable levels of vibration. To this end, this preliminary research attempts the possible reengineering of oil palm shells and ascertains the suitability of ROPS reinforcements in stabilising CBP−soil systems.

KEYWORDS:

• Recycling and reuse
• reinforcement
• sand bed thickness
• natural frequency
• peak displacement

Acknowledgements

Support for conducting the finite element simulations received from the High-Performance Computing (HPC) and the Unified Research Computing (URC) platforms at Monash University Malaysia is highly acknowledged. The authors acknowledge Ms. Shack Yee Hiew and Mr. Wai Hong Lim (former Bachelor of Civil Engineering students at Monash University Malaysia) for their support and assistance during the laboratory experiments of this study.

Disclosure statement

No potential conflict of interest was reported by the author(s).