Mechanical characterization of a FRCM system with aramid fiber fabric embedded in green high-strength cementitious matrix

Abstract

Fabric reinforced cementitious matrix (FRCM) system can be applied to strengthen existing RC structures. In this experimental study, aramid fiber (AF) mesh was used along with green high-strength mortar (f’_c= 75.6 MPa) incorporating fine waste glass powder as partial replacement of cement and 100% recycled fine aggregate. Test objective was to provide basic design parameters through mechanical characterization of the AF-FRCM system. Three different types of tests were conducted: Uni-axial test of tensile specimens; flexural test of composite short beams; and pull-off test of thin FRCM placed on top of normal strength concrete. Thickness of FRCM was about 10 mm while the volumetric ratio of the fiber fabric to gross volume was 1.3% (0.65% in each direction). Tensile test results showed that the load-displacement relationship of the FRCM was relatively ductile, while tensile behavior of the AF governed at the peak load. Nominal tensile strength of the FRCM cross-section was 6.4 MPa at 4.6% strain of the composite material. Short beam strength of 1.3 MPa was determined from flexural test of composite short beams (or interlaminar shear test) performed following ASTM D2344M. In the pull-off test, two different failure modes were identified: Interface failure or substrate failure in tension. Average pull-off strength was 2.84 MPa. Design values were suggested based on current test results of the AF-FRCM.