Normalized pressure impulse diagrams for RC members under bilinear blast loading

Terrorist bombing attacks in urban environments generate fully-vented or partially-confined blasts and magnify the effects of explosions. The current guidelines such UFC-3-340-2 simplify these blasts in the urban environments as bilinear pressure time history. Thus development of a normalised P-I diagram for the generic assessment of structures to establish safe response limits for bilinear blast loading would contribute significantly to the preliminary design of structures against blasts in the urban environments. In this paper, a previously validated finite difference model, together with the advanced moment rotation model, was used to simulate the response to broad ranges of structural members of given types under by-linear blast loading. Based on the simulated results, a series of PI diagrams were produced. Using the simulated results a normalised P-I diagram was developed for a given type of structural member under bilinear blast loading. Use of the normalized P-I diagram during the design phase of structures would substantially reduce costs by eliminating much of the time and effort involved in the preliminary design and analysis of structural members against bilinear blast-loads.C. W