Flexural Behavior and Cracking Characteristics of High Performance Fiber Reinforced Cementitious Composites according to Fine Aggregate Contents

Various methods have been used to reinforce the cementitious material such as mortar and concrete that have weak tensile strength. Major reinforcing method is to mix matrix with fibers which have strong tensile strength. Recently, High Performance Fiber Reinforced Cementitious Composites (HPFRCC) has been developed which shows multiple cracking behavior, that is different from conventional FRC. Related studies mainly have focusing on the mechanical behaviors according to fiber types and mixture proportions such as W/C and binder contents. However, study related to fine aggregate type and contents are insufficient. Therefore, this paper examines the fracture characteristics related to fine aggregate and contents, and reports the cracking behavior as well as mechanical behavior for various mixtures which have different fiber type and mixture proportions. From the results, it was useful to use silica sand as a fine aggregate for reducing fracture toughness as maintaining compressive strength and elastic modulus. It is showed that optimal silica-cement ratio was 0.8~1.0 to maximize flexural toughness and number of crack.