Nonlinear Analytical Design Procedure of Concrete Framed Strucrures Subjected to Distance Blast Load

Designing a structure that could face a threat from an external bombing to the structure needs finding the most effective way to meet the current standards requirements. When considering protection for a building, owners and architects must work together with structural engineers and blast consultants to find out the blast forces to bear that risk in mind and assess the desired protection levels. This paper is presenting the dynamic response of reinforced concrete moment resisting framed building subjected to blast loading. The building consists of ten stories with 5x5 bays having bay span of 6m and exposed to 30kg and 60kg with three different standoff distances of 3m, 5m and 7m respectively. A non-linear three-dimensional finite element model is used for analyzing the dynamic response of the structure. CSI SAP2000 finite element program is used for modeling and investigating the dynamic response of a concrete framed structure subjected to blast loading. The applied blast load as outlined in TM5-1300 Manual. The results obtained are in terms of time history function, displacements and influence forces considering the resistance of structure. Progressive collapse is also checked by providing plastic hinges in the structure as per ASCE/SEI 41-13 provisions as well as UFC 4-023-03 guidelines. The alternate approach followed shows that the structure is safe by removing middle periphery column. The results obtained shows that the plastic hinges formed in the middle column are higher compared with the internal columns. Further improvements adopted can be take place by applying special design for reinforcements as a apart from general design and it is recommended that guidelines on abnormal load cases and provisions on progressive collapse prevention should be included in the current Egyptian Code of Practice for special and important buildings.