The Finite Element Method (FEM) is commonly used in dynamic analysis of structures. However, its conventional techniques to improve the approximated solution to higher frequencies demand great computational cost. The Generalized Finite Element Method (GFEM) has been presented as a more efficient procedure to improve results in linear dynamic analysis [1, 2]. But there is still a need for more research in nonlinear dynamic analysis with GFEM, especially with the use of non-polynomial enrichment functions. Recently, safety and economy motivated the search for methods and theories for nonlinear analysis [3]. The objective of this work is to study the application of the GFEM in dynamic analysis of bars and plane trusses with geometric and physical nonlinearities, considering large displacements and the elastoplastic behaviour of structural steel. The analysis is developed with a script in Python, and the Newton-Raphson Method is applied to solve the system of nonlinear equations. Generalized finite elements for vibration analysis with different enrichment functions are proposed and investigated. The results of different GFEM approaches are compared to h and p FEM refinements, in terms of efficiency and convergence.