BLAST LOAD RESPONSE OF ONE-WAY REINFORCED CONCRETE SLABS RETROFITTED WITH FIBER REINFORCED PLASTIC.

The main aim of present work is to investigate structural behavior of one-way reinforced concrete slabs retrofitted with fiber reinforced plastic. Retrofitting is done to enhance bending and shear strength, to increase confinement and to repair damages caused by corrosion and cracking. In retrofitting RC slabs FRP is often used to enhance bending strength by putting it on the tensile side of the slab in the region with maximum anchor, which leads to significant increase in slab’s energy absorption capacity. Finite Element Method (FEM) is widely used in different fields for structural, electrical, heat, and mechanical engineering. In the case of blast analysis, due to excessive cost, the danger of experiments and extremely short duration of the test, numerical simulation is more attractive. Explicit dynamics analysis procedure based on the implementation of an explicit integration rule together with the use of diagonal (“lumped”) element mass matrices is used, which is computationally efficient for the analysis of large models with relatively short dynamic response and for the analysis of extremely discontinuous events or processes. Computer code ABAQUS is used for the analysis and the results are compared with available experimental results in the literature and good agreement has been observed. Also it can be concluded that numerical method used in this study has good agreement with experimental work. Influence of different geometrical parameters including number of layers, orientation of the fibers and the aspect ratio of slab has been investigated. Upon comparison with available experimental results, it is shown that modeling techniques have good accuracy. It is found that regardless of the orientation of the fibers, displacement of the center of slab would be reduced significantly. When fibers orientation angle with respect to the main load bearing direction of the slab is [-20°, 20°], the blast strength of the slab is maximum. For slabs with low aspect ratio, the more the number of layers, the higher the blast strength. For slabs with high aspect ratio, there is no significant difference between different fiber arrangements and increasing number of layers has no significant effect on blast strength of slabs. [ABSTRACT FROM AUTHOR]