Abstract: The area under resistance-deflection (R-y) curve ofreinforced concrete (RC) slab gives the energy which a RC slab can absorb when subjected tothe blast loads. For the RC simple supported one-way slab under blast loads,a bilinear model is used to simulate the R-y curvein the analysis of blast dynamic response. After comparing the areas underthe R-y curves of RC slabs with different reinforcementratios, the reinforcement ratio responding to the biggest area can be definedas the optimal reinforcement ratio. Because the effects of nonlinearity of the materialand the strain rate on the reinforced concrete and reinforcing steel shouldbe considered, a layered method is used to determine theR-y curves and the dynamic response of slabs. Thederived results can be used to optimiz design of RC simply supportedone-way slabs.