Impact resistance of hybrid fibre-reinforced oil palm shell concrete

• Hybrid fibre of 0.9% steel fibre + 0.1% PP fibre produced the highest impact energy.
• Uncrushed OPSC had better impact resistance compared to crushed OPSC.
• The lowest crack width was observed in the mix with 1.0% steel fibre.
• The highest compressive strength and compressive energy were found for 1.0% steel fibre in uncrushed OPSC.

This paper presents the results of an experimental impact test conducted using drop hammer on the plain and the fibre reinforced oil palm shell concrete (FROPSC) panels. The variables investigated are different contents of steel (0.75%, 0.9%, 1%) and polypropylene fibres (0.1%, 0.25%, 1%), with uncrushed and crushed OPS. The FROPSC with uncrushed OPS developed higher initial and final impact resistance compared to specimens with crushed OPS. The specimen with 0.9% steel + 0.1% polypropylene (PP) hybrid-FROPSC, developed excellent impact energy of about 17 kJ that was 60 times higher than the plain OPSC. Its impact ductility index (μi) of 42 is double the value compared to other specimens. It also showed excellent crack growth resistance due to secondary cracks formation. Final crack widths of FROPSC ranged between 0.079 and 0.507 mm. Further, the compressive energy of 785 J was found for specimen with 1% steel fibres.