Idealized pressure-time curve is adopted to simulate explosion load.The pressure-time curve represents simplified triangular load.Considering the influence of strain rate effect on steel

numerical simulation and analysis of dynamic response of jacket offshore platform under blast are performed by LS-DYNA software.Dynamic time-history response curves of key nodes in the upper deck

middle deck and vertical structure under different blast load are obtained.Results show that the absolute values of vertical displacements of the upper deck and middle deck nodes increase with increase of explosion load peak pressure.When the explosion load peak pressure ranges from 20 to 70 kPa

the material near these nodes is in the elastic stage.When explosion load peak pressure reaches 80kpa

the material enters the plastic stage.Horizontal displacements of elevation platform nodes increase with increase of explosion load peak pressure.Material near monitoring points in elevation platform enters plastic stage when explosion load peak pressure varies from 20 to 80 kPa.