Optimal design of RC panels against blast loads using energy-based approach

Abstract

Displacement-controlled approach is now being used by current guidelines such as TM5 and ASCE to design RC structures against blast loads. Although this method is easy to use, it may not obtain an optimal design. Actually the area under the resistance-deflection curve of a RC member represents its energy-absorption and thus a slab with different reinforcement ratios absorbs energy differently. The optimal reinforcement ratio for a slab corresponds to its maximum energy absorption capacity. A layered analytical model which allows for the varying strain rates over the cross-section was used to calculate a bilinear resistance-deflection relationship for a simply supported slab with different ratios so that the maximum energy absorption capacity of the slab as well as its optimal reinforcement ratio could be determined. Geometric size of the slab on the influence of the optimal reinforcement ratio was also investigated. The developed method is very useful to facilitate an optimal design to resist air-blast loads.