Investigation on damage mechanism of RC column under close-in explosion

Abstract

In order to investigate the anti-explosion performance of reinforced concrete column in ground floor,numerical simulations were conducted for the analysis on the damage process and failure mechanism of RC column under close-in explosion using LS-DYNA software.The model involved the effects of strain rate on dynamic constitute characteristics of reinforcing bars and concrete material,as well as the coupled interactions of explosive-air-structure.The results show that the damages RC column under close-in blast loads may be characterized that the front surface layer concrete firstly starts spallation,then the constrained concrete at the bottom and top end of column takes place the punching-shear failure,after then the continuously transverse deformation induces the global bending of RC column,followed by distributed cracking perpendicular to longitudinal axis of the column;the blast loads acting on RC column located at different reflection zone with the same scaled distance display rather large differences,therefore,the traditional scaled law is no longer adapted to close-in explosion situation.