Study On Impact Properties Of Thin-walled Rectangular Steel Beam

The structures of thin-walled rectangular steel beams have been widely used in the Offshore Engineering, which have to withstand all kinds of impacts, including collisions, storms, ocean waves, eruptions of crude, etc. The most possible impact style to the beam should be that of transverse, which is determined by the geometrical characteristics of the beam. In this paper, the impact responses of this thin-walled rectangular steel beam will be investigated both by experiment and finite element simulation.The impact experiments of the thin-walled rectangular steel beams are performed by Pendulum Impact Testing Machine, and the progresses of dynamic strain according to the node at the geometric center of the beam’s underside, the deformation of the middle section and defection of the beam after impact can be achieved. By using ANSYS/LS-DYNA, the impacts of thin-walled rectangular steel beam with different impact velocities are simulated based on the Johnson-Cook model. The reliability of numerical simulation is proved by comparing FEM results with experimental results, and further impact properties of the thin-walled rectangular steel beam are revealed.The impacts of several thin-walled rectangular steel beams and a thin-walled steel tube are numerically simulated. There are significant differences in the deformations, impact forces and energy absorptions by comparing the FEM results with different impact velocities. The amount of energy absorption and the absorption efficiency of the thin-walled steel structures rise with the increase of impact velocity. The numerical simulations show that, the thin-walled rectangular beam with depth-width ratio of2:1possesses better ability to resist deformation, the thin-walled rectangular beam with depth-width ratio of1:2possesses smaller peak value of impact force, and the thin-walled tube possesses excellent performances both of that.The objects of this research are to forecast the impact responses of the thin-walled steel structures by investigating the beam’s impact properties with experiment and finite element simulation, which can provide references to the structure design in order to reduce the loss and lighten the disastrous consequences of ocean’s ecology and environment caused by the impact accident.