This paper deals with a collabrative analyses combining existing analysis programs developped by two researchers.One is the elasto-plastic analysis program for composite beams, the other is that for exposed column-bases.Collaborative incremental analyses were conducted by exchanging stiffness matrices, incremental deformations, and restoring forces through Internet. Some precious informations could be obtained by collaborative analyses . For example, large fluctuation of column axial force could be obtained by collaborative seismic time history analysis, while such fluctuation could not be obtained by ordinary analysis.
