Production of hemp-gypsum composites with enhanced flexural and impact resistance

Abstract This work aims at designing, manufacturing and testing of gypsum specimens reinforced with hemp fabrics, in order to improve some properties of traditional gypsum boards, above all the impact resistance. Two different stacking sequences with both un-impregnated and epoxy impregnated hemp fibres were considered and two different types of fabric, that mainly differ in the weight areal density (380 or 190 g/m2), were used. Three point bending and impact tests at different energy levels were carried out in order to understand how the presence, the relative position of the hemp fabrics within the gypsum matrix and the gypsum-reinforcement interphase affect the mechanical response, so accurate comparisons with the un-reinforced gypsum samples were reported. In the light of the obtained results, the present investigation indicates that hemp fabrics could be used as suitable reinforce in gypsum boards, in order to improve their flexural and impact resistance. Indeed, respect to the unreinforced gypsum the use of hemp reinforcement allowed to reach an improvement of around the 100% and 320% of flexural strength and adsorption energy respectively.