Nonlinear collision analysis of heavy trucks onto steel highway guard fences

The design specifications of guard fences in Japan were reexamined and the revised<br />specifications were implemented from April 1999. Because of the huge consumption in time and cost to<br />test the performances of full-scale guard fences in the field, some assumptions are adopted while<br />modifying the design specifications, and numerical analyses are necessary to confirm the impact<br />performance and safety level of new types of steel highway guard fences. In this study, the finite element<br />models are developed for the heavy trucks and steel highway guard fences to reenact their behaviors, and<br />the solution approach is carried out using nonlinear dynamic analysis software of structures in three<br />dimensions (LS-DYNA). The numerical simulation results are compared with the full-scale on-site testing<br />results to verify the proposed analysis procedure. The collision process is simulated and it is also made<br />possible to visualize the movement of the truck and the performances of guard fences. In addition, the<br />energy shift of the truck kinetic energy to the truck and guard fence Internal energy, and the energy<br />absorption of each guard fence component are studied for the development of a new design methodology<br />of steel highway guard fences based on the energy absorption capacity.