Objectives  In order to evaluate the anti-explosion capability of the double-wall bottom grillage under the condition of underwater near-field explosion,

  Methods  the experimental model and explosion conditions were designed based on typical ship's bottom structure and anti-explosion. Through a underwater near-field explosion experimental test, the failure mode and the overall and local structural failure and deformation were investigated.

  Results  It can be seen from the failure and deformation of the model structure that there is no damage and obvious buckling of the inner bottom structure. Thus, under the action of underwater near-field explosion, the double-wall bottom grillage can effectively prevent the inner cabins from being destroyed and shocked by the near-field underwater explosion by absorbing the explosion energy through failure and deformation and to damaging and deforming energy absorption.

  Conclusions  The conclusion can provide a reference for the anti-explosion evaluation and guidance for design of double-wall bottom grillages.