In this present research study, development of the performance point of a bridge using stiffness-based damage index and drift damage to assess damage to reinforced concrete moment resisting frames, is proposed. It is shown that inelastic dynamic time-history analysis is performed on bridge subjected to earthquake records meanwhile damage of the bridge is computed by the stiffness-based damage index. Two relations between damage and drift are derived by applying a superposition that takes into account their effects. It is proven that the proposed point performance and damage indices are able to assess the damage index of bridge frames.The proposed approach is then checked by comparing predicted values to the ones considered as exact in the literature.