Using different mitigation materials to increase the resistance of underground concrete structure subjected to b last loads

Abstract

AbstractIn the last decades; the mass destructive weapons had been widely used like nuclearweapons. Nuclear bombs are destructive tool for human, weapons, equipment and allfacilities. The development of the nuclear bomb is a challenge for civil engineer s to protectpeople, facilities and weapons against hazards of nuclear explosions. That led them to usethe protective structures in military and civilian applications like underground concretestructures. It is difficult and sophisticated to use experimental nuclear test to predictbehavior of buried concrete structure response.The present paper presents a study to understand the behavior of underground concretestructure box section under blast load. Blast load resulted from a 2.0 kt (kiloton) weaponyield explodes at 200 m horizontal distance from the concrete structure , while the weaponyield is the measure of nuclear weapon, usually in kilotons or megatons of TNT equivalent .Numerical models were conducted using a 3-D nonlinear finite element program(AUTODYN).For saving time, an equivalent weapon yield of 0.03125 kt explodes at 50 m range afterensuring that the pressure resulted is the same, using the well known Scaling LawR/R1=(W/W1)⅓ , where R and R1 are the ranges of charges W and W1 respectively.Different mitigation material; half pyramid sandwich panel, honeycomb sandwich paneland aluminum foam were used to increase the resistance of underground concrete structure.This paper proposed also the best thickness of half pyramid sandwich panel underpressure ranges between 345 kpa to 1172 kpa (50 psi to 170 psi) namely 345, 552,758, 965and 1172 kpa.