| The compressive strength and modules of elasticity of concrete decrease a lot after fire. As a result, the aseismic capacity of R.C. Structures declines to some degree. In this paper, the nonlinear analysis program for fire damaged R.C. Columns is developed, and regression formulas for parameters of hysteric skeleton curves of fire damaged R.C. Columns have been given based on a great number of numeric results. Then, the effect of natural recovery of concrete mechanic properties on the aseismic capacity of columns is examined, and the earthquake response analysis has been done for two frame structures |