Residual load capacity of exposed and hardened concrete columns under explosion loads

The resistance behavior of columns subjected to contact or close-range detonation loading is the topic of the present paper. For this purpose, a test series with columns made of normal strength concrete and advanced concrete materials is conducted. Thereby, the experiments on standard reinforced concrete (RC) columns are the starting point and form the reference tests. Those are compared with investigations on columns with different constructive strengthening. Approaches for both retrofitting of existing columns and design of new constructions, are considered. A comparison of load-carrying capacity of exposed and undamaged columns for all examined elements leads to statements about the effectiveness of each protective measure. For the determination of original and residual strength static compression tests are used.The results demonstrate the positive influence of the different strengthening methods. A thin extra layer of absorbing material leads to an enormous increase of residual load capacity compared to unprotected reinforced concrete columns. Moreover, using strengthened design for a new construction results in increase of general load-carrying capacity.