| The steel reinforced concrete (SRC) members are composed of reinforcing bars, reinforcing steel and concrete. Because of the inherent large stiffness of the steel shapes and the distinctive interaction mechanisms with concrete in SRC members, their response characteristics and failure modes under blast loading are expected to differ from those of normal reinforced concrete (RC) columns. The dynamic characteristics and failure mechanism of SRC columns under blast loading is very complicated because of non-linear high-dynamic response of the constituent materials , the transient stress wave , and the material interaction between reinforcing steel and concrete.This paper presents a numerical simulation study on the response of SRC columns subjected to blast loading using hydrocode LS-DYNA, putting particular focus on the failure modes and failure mechanism. The main jobs and conclusions are as foliowings:(1) The Concrete-Damage Model (material model 72 ) which incorporates most of concrete dynamic characteristics such as strain rate effect, damage accumulation, etc., is suitable to the concrete. The erosion technique is adopted to model the spalling process of concrete. The TIEBREAK_SURFACE_TO_SURFACE contact mode is used to simulate the bonding and slipping between concrete and steel shapes; The LS-DYNA software is used as the tools and the precise parameters which are used to simulate SRC columns on the load of blasting are obtained based on the test results of other researchers through reading the related references.(2) The basic periods of whole structures which usually are some seconds are much longer than that of structural members and the duration of blast loading which are usually only some milliseconds. On the load of local blast, the structural members can be separated apart from the whole structures with the end's restricted condition being taken into consideration.(3) The dynamic response of SRC columns under blast loading can be classified...
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