Finally , the analysis of elastic - plastic time - history on r . c . frame structure with special - shaped column is conducted by plane structure elastic - plastic time - history analysis the procedure ndas2d ( nonlinear dynamic analysis of structures in two dimensions ) programmed in structural system composed of bar , 24 earthquake waves is adopted according to site classification 第四,采用桿系模型編制的平面結構彈塑性地震響應分析程序ndas2d ,對鋼筋混凝土異形柱框架結構進行了彈塑性動力時程分析。