Analysis Of Nonlinear Dynamic Response Of Ship Structure Under Impact Load

In the process of jacket launch, when the rocker arm of bar ge reverses and back to its due place, the ship structure will suffer a large impact load in a very short tim e at the moment of rocker arm collision with stern. Due to the huge impulsive load, the members in the impact region will probably enter into the state of plastic flow. And it is likely to induce buckling, rearing, any types of da mage and failure. Therefore, paying attention to the researches on the nonlinear dynamic response of ship collision is very necessary.Aim on the above-m entioned problems, the dynam ic response of the stern of large launching bar ge subjected to impulsive load of the ro cker arm is investigated. Based on ANSYS/LS-DYNA procedure, and co mbining with prac tical engineering, this paper discusses the ke y techniques of num erical simulation of the collsio n problems like that s tructures subjected to the s imilar impulsive load w hich revolves around a fixed axis, such as elem ent formulations, Gauss inter gral points, hour glass energy, m aterial m odels and so on, and then, the basic procedure of modeling is described. Furthermore, considering the ef fect of the m aterial model, strain ra te and failure strain, a propore model is established, and the damage behavior of the stern of barge subjected to im pact load of rocker arm with dif ferent speed is cacula ted and analyzed which including stress- strain, deformation, displacement, energy absorption and collision force, and the relation curves are created as well.Simply speaking, by calculating and anal yzing the collsion between rocker arm and stern of launch bar ge, the dynam ic m echanical process of elastic-plastic deformation about the structure that subject ed to the sim ilar impulsive load which revolves around a fixed axis is researched in this paper.