A NEW METHOD FOR IMPACT PROPERTIES MEASUREMENT OF NATURAL FIBRE-REINFORCED CEMENT COMPOSITES

摘要

For safety reason, the need for civil or military structures to sustain harsh impact loads has been emphasized more and more recently and fibre-reinforced composite materials have an advantage. In this study, impact crack properties of coir fibre-reinforced cemen-titious composite (CFRCC) materials were investigated using a modified Charpy impact machine for penetrated impact loading. The impact deceleration was measured with a commercially available ceramic shear ICP ® accelerometer; the temperature of the CFRCC specimens' broken surface during impact tests was determined using a highspeed thermal camera; and the acoustic emission during the impact moment was also recorded. Coupling with dispersant, defoamer and wetting agents, the impact resistant energy of CFRCC samples was improved by 1. 44%, 5. 33% and 20. 88% after ageing for 7, 28 and 180 days respectively. Thermal emissivity in the fracture surface of the CFRCC was significantly lower than with the conventional mortar. Results of acoustic noise during the breaking of the composites also showed that CFRCC could absorb more energy before it failed completely, leading to lower sound energy emission for CFRCC than for conventional mortar.