The aim of this research is to investigate the failure modes of typical Angelina beams subject to bending and to propose a simplified approach to assess the ultimate load to each of the relevant collapse modes. Finite element analyses were conducted in four Angelina beams with different cross sections. The beams were subjected to four-point bending load, and both short and long spans were considered. Results show that as slenderness increases, the Vierendeel mechanism and plastification of tees tend to interact with webpost buckling and tee torsional buckling. Also, nonlinear finite element analyses revealed a unique principal stress pattern in Angelina beams that inspired the development of a simple two-dimensional model to estimate Angelina beam capacity. The calculation of beam capacity in the simplified model include the implementation of the strut and tie model to verify the buckling capacity of critical members and the evaluation of nonlinear analyses results in the structural analysis program SAP 2000 to obtain the plastic load. The similarity observed between load-displacement curves of the finite element model and the simplified model explains the process of stress redistribution and hinges formation observed in the material nonlinear analyses performed using the finite element program ABAQUS. Although many authors have characterized the Vierendeel mechanism as the formation of four plastic hinges at openings corners, this study concluded that for the studies Angelina beams there is a stress redistribution after the initial yielding and that the final failure condition happens at two critical sections.