Tensile characterization of multi‐ply fabric‐reinforced cementitious matrix strengthening systems

Abstract

AbstractFabric reinforced cementitious matrix (FRCM) is a composite consisted of high‐strength fibers impregnated in a cement‐based mortar, and is commonly used for strengthening reinforced concrete and masonry structures. Comprehending the tensile behavior of FRCM is important to achieve a reliable and accurate design of FRCM strengthening systems. The current paper reports on the results of an experimental study on the tensile characterization of FRCM. A total of 40 FRCM specimens (410 × 50 mm, varied in thickness) were prepared and tested. The tensile characterization tests were conducted according to AC 434 guidelines using clevis‐grip mechanism. The tests were used to assess the effect of two parameters: (a) fabric type (carbon/glass) and (b) number of fabric plies (one/two/three/four). The results showed that the tensile strength of carbon‐FRCM specimens was approximately 1.33 times that of the glass‐FRCM counterparts. Three distinct failure modes were observed, namely, (a) ductile fabric slippage in carbon‐FRCM (up to three plies of fabric); (b) brittle fabric delamination in carbon‐FRCM with four plies of fabric; and (c) brittle fabric rupture in glass‐FRCM systems. The FRCM tensile load‐carrying capacity had proportionally increased with the number of fabric plies; less significant effect (within 20%) was observed on the corresponding ultimate tensile stresses (considering the net fabric area as the effective area).