![]() The stiffness of the FRCM system is usually the same as that of the sum of all axial fibers in the cracked phase as resistance of the mortar is lost due to crack(s). 1a: (1) linear behavior to the first cracking in the uncracked phase (2) stable behavior with slowly increasing resistance accompanied by intermittent load drop and recovery due to mortar cracking during the cracking phase and (3) linear behavior up to the ultimate in the cracked phase. Resulting tensile behavior of the FRCM system is typically trilinear as shown in Fig. The ends of the thin and prismatic specimens are subjected to out-of-plane compressive stress applied by a hydraulic means (such as the hydraulic grip of UTM) during test. ![]() In one approach, a clamping grip is used. It is well known that two different approaches exist when evaluating the tensile performance of a FRCM system. The C-FRCM considered in this study includes potential application in a form of the prefabricated FRCM (You et al., 2020). The experimental programs included tests for the basic mechanical characterization (tensile test and lap-splice test) and tests for the application of the C-FRCM for the purpose of concrete column strengthening. ![]() carbon fiber (CF) was used in a form of 2D fabric along with a green high-strength mortar utilizing recycled materials such as finely ground waste glass powder and recycled fine aggregate. In this study, carbon fiber-reinforced cementitious matrix system (C-FRCM) is utilized: i.e. Others tried multiple layers of the fabric embedded in the pressurized dense mortar (Peled et al., 2009). Some researchers tried to use the strain-hardening type cementitious matrix (Al-Gemeel & Zhuge, 2018 Gong et al., 2020). One to several layers of fabrics made of various fibers such as carbon fiber, glass fiber, aramid fiber, basalt fiber, and polyparaphenylene benzobisoxazole fiber (PBO) have been used. The FRCM system has advantages over the external FRP strengthening, such as its applicability on wet surfaces, good performance under elevated temperatures in addition to so called “breathability” of the inorganic matrix as compared to the much denser polymer impregnation of fibers of the FRP. The FRCM systems are also applied to externally strengthen reinforced concrete (RC) members such as RC beams, slabs, columns, walls, and beam–column joints (Donnini et al., 2019b Hadad et al., 2018 Larbi et al., 2013 Tello et al., 2021). Low-to-normal strength inorganic matrices with 10–45 MPa compressive strength typically have been utilized when the FRCM systems are used toward external strengthening of the masonry elements such as masonry walls (Caggegi et al., 2017 Carozzi et al., 2017 Leone et al., 2017 Koutas et al. The FRCM system is called textile-reinforced concrete or mortar (TRC or TRM) in Europe. single or multiple layers of 2D (or 3D) fabrics are impregnated by inorganic matrix such as cementitious mortar, lime mortar, or mortar comprising cement and polymers. The fabric-reinforced cementitious matrix (FRCM) system evolved from ferrocement where the metallic reinforcement is replaced by fabrics of dry fibers (ACI 549.4R-13): i.e. Compressive strength increased by 10–41% while ductility also increased by 6–45% indicating applicability of the prefabricated type C-FRCM in the future. All test results showed strain-softening behavior. Plain concrete cylinders and prismatic specimens were laterally confined by C-FRCM and subjected to uniaxial compression. The required splice length was about 170 mm for the single fabrics and it was about 310 mm for the double fabrics. From the lap-splice tests in direct tension, an increased lap-splice length was required for the double fabrics over that for the single fabrics. Full strength of the carbon fabric was developed in all tensile tests while the C-FRCM with two fabric layers (with axial fiber amount = 0.59% by vol.) showed pseudo-ductile behavior. Nominal strength of the C-FRCM with two fabric layers was 11.0 MPa while it was 7.4 MPa with one fabric layer in tension. Test variable for the tensile test was number of fabric layers (one or two layers). Test plans were developed in due consideration of prefabricated C-FRCM for strengthening concrete columns: 14 tensile tests, 12 lap-splice tests, and 6 uniaxial compression tests of plain concrete specimens confined by C-FRCM were performed. ![]() Green high-strength mortar was used in this study which actively utilized recycled fine aggregate and fine waste glass powder to partially substitute cementitious binder. Results of an experimental study aimed to evaluate tensile performance, lap-splice length of carbon fabric-reinforced cementitious matrix system (C-FRCM), and performance of concretes confined by C-FRCM are presented. ![]()
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