Enhanced, unconditionally stable, explicit pseudodynamic algorithm

In performing a pseudodynamic test, an explicit method is generally preferred over an implicit method since it involves no iteration procedure or extra hardware that is often needed for an implicit method. However, its integration time step is usually limited by stability. Hence, it is very promising for the pseudodynamic testing if an explicit method can have unconditional stability, which might eliminate the limitation on time step for the testing of a multiple degree of freedom system or a substructure system. Although an explicit pseudodynamic algorithm with unconditional stability has been successfully implemented and its superior characteristics have been identified, an enhanced unconditionally stable explicit pseudodynamic algorithm is further proposed. In this study, it is verified that both explicit pseudodynamic algorithms possess the same numerical characteristics in the step-by-step integration. However, the newly developed explicit pseudodynamic algorithm shows better error propagation properties when compared to that developed previously.