Numerical Analysis for Progressive Collapse and Protection of Underground Structure under Internal Blast Load

Dynamic response of an underground structure with the protection of foamed aluminum under internal blast load, compared with that without any protection, has been investigated numerically in this paper. The three dimensional model of the two-storey and two-span underground structure covered with soil around was built with the explicit dynamic analytical software LS-DYNA. The three-stage simulation method （TSSM） is proposed. And the middle column of the structure is covered with foamed aluminum which provides a better protection for the column under the blast load. The solid-fluid interaction algorithm, the erosion algorithm and the stress initialization method are employed in the calculation. It is found that, under the protection of foamed aluminum the collapse resistance of the structure has been improved greatly compared with the structure without any protection.