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چکیده
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Increasing concerns about terrorist attacks and the possibility of accidental
explosions in or close to the buildings has increased demands for assessment and
retrofit of structural elements against blast loads. In order to avoid hazards and
expenses included in the real blast tests, numerical simulation has found to be an
efficient alternative for investigation of structures exposed to blast loads, provided
that the material model is properly selected and correctly calibrated. In the context
of structural failure due to blast loads, concrete structures are more likely to be in
danger as a consequence of concrete brittleness. As a remedy to this shortcoming,
several fiber reinforced and composite concrete materials have been proposed and
successfully verified in diverse technological environments. Among these new
generations of enhanced concrete materials, Ultra-High Performance Fiber
Reinforced Concrete (UHPFRC) possesses remarkable tensile strength, and its
reasonable ductility and significant ability in energy dissipation prior to failure, has
been sufficiently encouraging for researchers to examine performance of such
material in blast resistant columns. Herein some reported real blast tests on
UHPFRC coulmns are simulated using ABAQUS, adopting suitable damageplasticity model for the UHPFRC material. Computed responses for weak and
strong explosions nearby the columns has been found in good agreement with the
real blast test results. Ability of the developed model in prediction of the real
responses, reveals validity and reliability of the simulation for further numerical
and parameter analyses. It was observed that the maximum displacement of a model
is only 25 millimeters and about 60% will be reduced to non-resistant ones, When
it is used with the UHPC jacket for the retrofitting of RC columns. Also, by
introducing a pressure-impulse diagram for assessing damage to the column, blast
resistance capacity of the column against the contact and far explosions inc
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