Abstract—This study investigates static and dynamic performances of flat-plate and flat-slab systems made with unconventional type concrete (i.e., low strength concrete) both experimentally and numerically. To do this end, in a first step, the specimens are tested under both static and dynamic loads. Later, all of the specimens are retrofitted (i.e., partially damaged specimens after dynamic load) via the use of ferrocement technique and tested again under dynamic loads to investigate the performances of the retrofitted specimens. Total six slabs with columns are made for two different concrete mix design ratios such as 1:1.5:3 and 1:2:4 (cement: fine aggregate: coarse aggregate). The models are: flat-plate labeled as M1, flat-slab with drop panel namely M2 and flat-slab with drop panel and column capital termed as M3. And their performances are evaluated by performing static and dynamic tests via shake-table. Additionally, numerical simulations are performed by using SAP2000 and compared with the experimentally obtained response. It is observed herein that the punching shear failure occurred at the slab-column connection for most of the un-retrofitted cases, while the performances have improved significantly due to retrofitting. The outcome will assist the real engineering problem to mitigate the damage of flat-slab systems in general.