In bridge design, engineers must consider impact loads from heavy trucks colliding with piers or overheight trucks colliding with girders. This paper presents the basis of a procedure for estimating the load and displacement capacity of reinforced concrete (RC) members under collision loads. A series of physical experiments were conducted to confirm the procedure applicability in predicting the flexure impact resistance capacity of RC members. The basis of the procedure relies on performing Monte Carlo statistical (MCS) simulations in conjunction with the displacement-based design method. Test results show that the procedure is capable of correlating damage levels in RC members to loads resulting from collisions. Results from the MCS simulations indicate that the measured peak and residual displacements from the physical experiments were predicted within a 95% confidence interval. The proposed methodologies provide performance-based tools for assessing the vulnerability of RC members under impact loads.