Work

Punch-shear behaviour of biochar-modified jute fibre-reinforced epoxy composites under different indenter geometries

Year: 2026

Type: article

Abstract: The punch-shear behaviour of jute fibre-reinforced epoxy composites containing biochar at 0, 5, 10, and 15 wt.% was systematically investigated under quasi-static punch-shear loading using two indenter geometries: a flat circular nose and a hemispherical nose. Ten mechanical response parameters, including maximum shear strength, initial stiffness, yield stress and displacement, modulus of resilience, shear toughness, ductility index, brittleness index, and post-peak softening rate, were analysed. Under flat circular loading, the unfilled composite exhibited a low initial stiffness of 2.76 MPa/mm but a relatively high total toughness of 23.99 MPa·mm attributable to its large displacement capacity. Biochar addition at 5 wt.% raised stiffness dramatically to 11.83 MPa/mm whilst peak strength was maximised at 10 wt.% (10.97 MPa). Under hemispherical loading, the composite with 15 wt% biochar produced the greatest total energy absorption of 41.88 MPa·mm. Indenter geometry strongly modulated failure mode and energy absorption across all compositions. The findings provide practical guidance for optimising biochar content in jute composite panels for applications governed by concentrated or distributed punch shear loading.

Source: Polymer Testing

DOI: 10.1016/j.polymertesting.2026.109333