Development of Angle Ply Cement Based Composite Laminates

Novel cement based materials with improved structural and mechanical properties are developed. High fiber content cementitious laminates are manufactured using a computer controlled closed loop system for filament winding. Continuous fiber cement based composites consisting of unidirectional lamina, [0/90/0], and [0,+45n,+90n] are manufactured using Alkali resistant glass fibers. Mechanical properties of the composites are measured using uniaxial tensile specimen. Test results indicate that the tensile strength of unidirectional fibers is as much as 50 MPa. In the case of cross ply laminates, various mechanisms of ply delamination and crack deflection increase the strain capacity to the order of 2%. In addition, fracture toughness as much as two orders of magnitude higher than the conventional FRC materials is obtained. The extent of matrix cracking, ply delamination, and crack deflection mechanisms are studied by means of fluorescent microscopy