Explosion load becomes an important research field in recent days, due to the terrorist attacks, that occur all over the world. A bomb explosion within or immediately nearby a building can cause catastrophic damage on the building's external and internal structural frames, collapsing of walls, blowing out of large expanses of windows, and shutting down of critical life safety systems. Loss of life and injuries to occupants can result from many causes, including direct blast effects, structural collapse, debris impact, fire, and smoke.
This thesis presents the various analysis methods available to simulate the loads from a high explosive blast on structural buildings. Blast wave phenomena and blast load parameters are investigated. An analytical finite element model (FEM) for different 3D structural building systems subjected to blast loading is performed using SAP 2000 software package. Expremental and analytical studies from litrauture work are used to verify the proposed FEM. Different types of steel structural systems for low and high rise bulidings are invetigated to study their roubstness, connection’s types, collapsability limt and capability under blast loads. Three structural systems are investigated; moment resisting frame (MRF), Braced Frames (BF) and Eccentric Braced Frames (EBF). Three, ten and twenty story building are analyzed using elastic time history for chemical blast loads.
It was found that the moment resisting frames have a large number of dissipative zones, which are located near to the beam to column connections. Therefore, it can dissipate more energy than any other system. For braced frames, unacceptable large structural damage can occur due to the failure of bracing elements after very short time. A suitable system between the lateral rigidity of bracing and the ductility of moment resisting frames can be obtained using eccentric braced frames. Mainly axially loaded members resist the blast load, but the eccentricity of the bracing allows the energy dissipation by means of cyclic bending and shear behavior in an element known as a link.
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