Not only new structures but also existing structures have recently been required to survive severe earthquakes, such as the Hyogoken-Nanbu Earthquake, without any collapses. To evaluate seismic performance of these structures against severe earthquakes, reliable simulation tools to analyze their response behaviors up to the collapse stage are demanded.
      The Railway Technical Research Institute (RTRI) has developed a new simulation program which can analyze the dynamic response of reinforced concrete (RC) structure from infinitesimal to large deformation stages and finally up to the collapse under the earthquake loading. The Applied Element Method, which is a new analysis technique to solve the nonlinear behavior of structure, is adopted in the simulation program. This program can also be applicable to evaluate the seismic strengthening effect of the steel jacketing and other new innovative methods for concrete structures. The simulation program has been verified with loading test results and actual damages of structures suffered during severe earthquakes, so that it can trace the collapsing process of structure. The analyzed results are presented to visualize the dynamic response behavior and the process of collapse (see Figs.1 and 2).
      The simulation program will be upgraded to an intelligent system to output effective and economical seismic countermeasure, conducting seismic diagnosis, selection of strengthening method, and selection or preference of optimal member for strengthening.