Impact Behavior of Sisal Fiber Cement Composites under Flexural Load.

The impact response of unidirectional continuous sisal fiber-reinforced cement composites was investigated. An impact test setup based on a free-fall drop of an instrumented hammer on a three-point bending configuration test was used. The effect of impact energy on the composite response was investigated by using three different drop heights. Mechanical properties obtained under impact loading were compared with static three-point bending tests. A comparison with the impact behavior of glass fabricreinforced composites was addressed. Furthermore, damage mechanisms were investigated by characterizing the cracking patterns during the impact event using a high-speed digital camera. It was observed that while the maximum flexural stress values were in the same range for static and impact tests, the absorbed energy increased up to a maximum level of 0.0090 kJ/in.² (14.0 kJ/m²) for the impact energy of 20 J. The damage process was initiated by tensile and shear cracks. Delamination of the plies within the continuous fiber composites was observed only when the impact energy was 27 J. [ABSTRACT FROM AUTHOR]