## 1 Introduction  
The proposed model follows a polygonization approach for discretizing the cross section of a beam element, whose theoretical part has been extensively described in Part I [1] of this paper. As a follow-up, the developed model has been validated by comparing its analytical results with those of a wide variety of experimental ones from the literature. Since it aims to be efficient for any cross-section shape and loading pattern, representative experimental studies have been chosen from the literature, which are used in this paper. It must be pointed out that the experimental research on the inelastic response of reinforced concrete linear elements under bending due to lateral cyclic loading combined with constant or variable axial load is quite limited. This research mainly uses predefined uniaxial or biaxial loading paths of the lateral load while the majority of specimens are of classic cross-sectional shapes (orthogonal, circular, etc.). Moreover, a serious part of this research is focused on the study of specific inelastic parameters such as the plastic hinge length, the influence of the reinforcement ratio on the moment capacity of the members, the moment curvature relation, et al. Only a limited number of experimental results are provided in terms of lateral load \(P\) vs. horizontal displacement \(\delta\) or in terms of bending moment \(M\) vs curvature \(\varphi\) for a specific cross section of a member. Focusing on the experimental investigation carried out over the last three decades and setting the completeness of the provided experimental data and results (in terms of \(P\)-\(\delta\) or \(M\)-\(\varphi\)) as criterion, representative examples for orthogonal cross sections, solid or tubed, can be found in references [2; 3; 4; 5; 6; 7; 8]. For circular or ring cross sections in references [9; 10; 11; 12; 13], for L-shaped column specimens in references [14; 15], and for T-beams in references [16; 17]. These references are reported in chronological order. For the needs of the validation of the present mathematical model, representative experimental results were collected from the previous mentioned literature, using as criteria the completeness of the provided data, i.e., geometry and reinforcement details of the specimens, mechanical properties of concrete and reinforcing steel, detailed records of the imposed loading paths (in terms of imposed lateral displacements or forces), and analytical experimental results in terms of \(P\)-\(\delta\) or \(M\)-\(\varphi\). The records of the imposed loading paths as well as the resulting experimental hysteretic loops were digitally scanned in precision for purposes of comparisons with the analytical results of the present model. Thus, in the present study, comparisons have been made for column specimens with cross section shapes as: rectangular ([PERSON] [3], [PERSON] and [PERSON] [2]), hollow rectangular ([PERSON] et al. [8]), circular ([PERSON] et al. [11]), hollow circular ([PERSON] [13], [PERSON] [10]), and L-type ([PERSON] and [PERSON] [15], [PERSON] et al. [14]). A T-beam specimen ([PERSON] et al. [16]) has also been studied. These experiments fall within the present limitations of the model concerning slender elements without significant influence of the bond slip phenomenon. Furthermore, various representative loading paths have been considered in these experimental studies, such as: (a) cyclic uniaxial or biaxial loading with varying displacement values, (b) butterfly-shaped nested displacement paths, and (c) square-shaped nested displacement paths with increasing or decreasing order. In these displacement paths, axial load is either constant or varying throughout the experiment. The proposed model has been verified on a 2D one-bay one-story frame ([PERSON] and Karayannis [18]) subjected to in-plane cyclic loading. In the following sections, a description of each experiment along with the analytical results of the model is presented.