In this paper, moment-curvature behavior of reinforced concrete column with constant axial load is determined
using finite element method and then it is introduced to a single degree of freedom (SDOF) model based on EulerBernoulli theory. Using this SDOF model, dynamic response of the RC column under the blast loading is estimated.
The introduced SDOF includes secondary moments (P-δ) effects, nonlinear behavior of the material and effects of
strain rate on concrete and steel materials through the time calculation of the model. Results obtained from SDOF
model for transverse displacement of RC column under blast loading is compared to analysis by finite element software
OPENSEES. Then, introduced SDOF method is used for drawing Pressure-Impulse (P-I) diagram of the column with
considering the presence of axial compressive load. According to the results, introduced SDOF model has simple and
quick computations and accuracy of predictions is acceptable.