Retrofit for Blast-Resistant RC Slabs with Composite Materials

Synopsis: This research program was initiated to examine the feasibility of assessing the blast-resistant capacity of reinforced concrete (RC) slabs using the displacement based design (DBD) method. In order to achieve this objective, five RC slabs were tested under real blast loads in the out-of-plane direction. One of the slabs was used as the control unit to establish a baseline for comparison in terms of performance for the other four slabs, which were strengthened with fiber reinforced polymer (FRP) and steel fiber reinforced polymer (SRP). The explosive charge weight and stand-off distance required to impose a given damage level were predicted by the DBD method. Test results showed that the blast loads were effectively estimated and the damage levels observed from the field tests correlated well with the predicted levels. In addition, test results corroborated that the blast-resistant capacity of RC slabs can be effectively increased by strengthening using FRP composites. The main conclusion that can be drawn from these tests using improvised explosive devices (IDE) is that RC slabs retrofitted on both sides have a higher blast resistance capacity than those slabs retrofitted only on one side. This paper discusses these experimental results along with the analysis steps used to predict the blast charge and standoff distance to impose a given damage level.