The common techniques for the numerical analysis of the structural members by two-dimensional finite elements; are plane stress and plate bending analysis. Using layered elements, the rectangular concrete members can be modeled and analyzed taking into account the effect of material and geometrical nonlinearities. In case of strengthening by external layers, plane stress or plate bending analysis can analyze the concrete member with its original reinforcement and strengthening layers only in parallel sides. In this research, a combination by the two previous technique; plane stress and plate bending is driven to be capable for simulating the concrete member with its internal longitudinal reinforcement, stirrups as well as the external strengthening layers on the four sides. To accomplish this aim, a new innovated compound element was generated in this research. A computer program based on 2-D finite elements is developed. Isoparametric degenerated element with eight nodes and five degrees of freedom in each node is chosen to achieve the process. Each element consists of different concrete, steel and strengthening laminates. Longitudinal and transverse reinforcement, as well as the additional strengthening layers are represented by smeared layers. The nonlinear behavior of RC members like stress-strain relations of concrete and steel, tension stiffening, and concrete crushing, are considered. Studied examples were investigated to show the applicability and accuracy of the suggested model. In these cases of study, different techniques of finite element methods such as laminated plate bending and plane stress elements as well as 3-D finite elements were applied separately and compared with the new compound laminated elements. The developed constitutive model which depends on both laminated plate bending and plane stress techniques has proved to be capable to solve any reinforced concrete member strengthened with additional external layers in different sides with accurate representations and acceptable results.