The presented research aims to examine local fatigue failure modes of Glass Fiber-polymer Composite (a.k.a. GFRP), particularly how the bending of the Web-to-Flange Junctions (WFJ) and tensile loading of the material affects the composite's fatigue resistance. By conducting experimental analyses, the study investigates GFRP's efficacy both as a material and as a component element, drawing parallels with Eurocode standards for steel and concrete. The coupon tests under static and fatigue loading conditions provided an empirical data on the Ultimate Limit State (ULS) and fatigue resistance of the GFRP composites, including a better understanding of the effects of variation in the facing’s thicknesses in the web-core composite on the fatigue response. Subsequent three-point bending tests on the WFJ provided the insights into the strength of WFJ with the first indications on the governing failure mechanisms in the WFJ.