الفهرس 
LITERATURE REVIEWOnly 14 pages are availabe for public view
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Abstract
6.1 RC SLABS UNDER BLAST LOADS
The present study proposes the 3-D nonlinear finite element model to discuss the behavior of reinforced concrete slab against blast load. The numerical modeling is carried out using the proposed 3-D finite element model to predict the response of slab and the numerical results are compared with the experimental available data in literature. The numerical model is carried out on three different models (concrete slab without reinforcement, concrete slab with single reinforcement and concrete slab with double reinforcement) against blast loading under different charges of TNT (3,5,10kg) and boundary conditions (all edges continuous, two edges continuous and one edge continuous) . The results obtained from different models are presented in terms of Von-Mises stresses, deflection and concrete damage against different charges of TNT and boundary conditions.
The following conclusions are drawn:
• The deflection decreases by 23%,30%,50%from concrete slab without reinforcement model to concrete slab with single reinforcement against 3,5,10kg TNT, respectively.
• The deflection decreases by 22%,27%,36% from concrete slab with single reinforcement model to concrete slab with double reinforcement against 3,5,10kg TNT, respectively.
• The use of double layers of Reinforcement steel adopted in the RC slab lead to decrease of deflection against different charges of TNT.
• The compression reinforcement steel leads to redistribution of normal stresses in both concrete and steel Rft.
.The present study proposed the 3-D nonlinear finite element model to study the response of reinforced concrete buildings subjected to blast loading under varying of mass of TNT and different reinforcement ratio. The numerical modeling is carried out using the 3-D finite element model to predict the response of RC Building and results are compared with the verification model. The proposed 3-D finite element model has been carried out on two different models (Flat slab system and solid slab system) against blast loading under different charges of TNT (5, 10, 20kg). The numerical results obtained from different models are presented in terms of Von-Mises stresses, deflection and concrete damage against varying mass of TNT.
The following conclusions are drawn:
• The flat slab system has deflection less than solid slab system under 5,10kg TNT.
• The flat slabs system has compression & Tension Damage in concrete less than solid slabs systems under 5 and 10kg TNT, however the two systems reach the maximum damage in concrete under 20kg TNT.
• The flat slab can withstand blast loads better than solid slab having same spans under different mass of TNT due to existences of double Rft and larger thickness of slab using Different spans for the two systems need further investigation.
• The Damage happened under blast loads in flat slab system where in columns while the damage happened under blast loads in solid slab system where in beams so it is recommended to use the solid slab system.
• Using double Rft mesh in slabs is recommended regarding the statical system to decrease the deflection.
• Using continuous spans give better results than using single span.
6.3 SUGGESTIONS FOR FUTURE RESEARCH
• Study the effect of different standoff distance and blast origin location on RC buildings under blast loads.
• Compare the results from interior and exterior explosion on RC Buildings.
• Compare the response of RC slabs under blast loads with different aspect ratios.
• Compare response of different statical systems (Prestressed concrete and Panalled beams) under blast loads.
• The effect of different kind of charge material for explosion (TNT- C4- RDX- HMX).