IMPROVED EXPLICIT METHOD FOR TIME HISTORY ANALYSIS

摘要

In this paper, an explicit integration method is presented. This method is shown to have the same numerical characteristics as those of the constant average acceleration method for a linear elastic system. This implies that it is unconditionally stable for linear elastic systems. However, it shows very different stability properties for nonlinear systems. In fact, it has conditionally stability for an instantaneous stiffness hardening system while it remains unconditionally stable for an instantaneous stiffness softening system. The conditional stability property is much better than for the Newmark explicit method for instantaneous stiffness hardening systems. Meanwhile, this method involves no iterative procedure in the step-by-step integration. Thus, it is very promising for time history analysis since it is explicit and has improved stability properties.