The development and demonstration of a new inelastic steel girder bridge rating method, called Residual Damage Analysis(RDA), is presented herein as a practical bridge analysis technique. RDA is a method for assessing the residual moments and deformations that are set up in a bridge beam that has been loaded into its inelastic resistance range. RDA combines classical elastic conjugate beam theory with empirically formulated moment-rotation relationships for both midspan inelastic positive moment and interior support inelastic negative moment hinging. RDA incorporates the ALFD(Alternative Load Factor Design) concepts of extending the load carrying capacity of steel members beyond the elastic range be taking advantage of inelastic moment redistribution. RDA makes use of the recently proposed rating factors to provide an acceptably low probability of exceeding inelastic serviceability limit state, which is defined by limiting the permanent set that may be allowed in a given span. And also, for 2-span continuous composite plate bridges, the results of RDA ratings are compared with those of LFD(Load Factor Design) ratings and those of WSD (Working Stress Design) ratings.