Title

FINITE-ELEMENT MODELING AND MODEL VERIFICATION OF STEEL W-BEAM GUARDRAILS SUBJECT TO PENDULUM IMPACT LOADING

Document Type

Journal Article

Publication Date

1998

Subject Area

mode - rail

Keywords

W beams, Trade off analysis, Tension, Tensile strain, Tensile loading, Speed, Simulation, Posts, Pendulum tests, Impact velocity, Impact, Guiderails, Guardrails, Guard rails, Guard fences, Finite element method, Finite element analysis, Experimental data, Computer simulation, Comparison studies, Cables, Alternatives analysis, Acceleration (Mechanics)

Abstract

The experimental and simulated response of steel W-beam guardrails to pendulum impact loading for impact velocities of 20 km/h, 30 km/h, and 35 km/h are presented. The guardrails were supported by four posts and cable-anchored at each end to ensure that the full tension capacity of the rail could be developed. Experiments carried out with a 912-kg impact pendulum are compared with LS-DYNA finite-element simulations of the impact events. Pendulum tests were completed at the Turner Fairbank Highway Research Center of the Federal Highway Administration. Acceleration, velocity, and displacement time histories are compared for the pendulum impact test and the LS-DYNA simulations. Comparison of the experimental and simulation acceleration records is made using the Numerical Analysis of Roadside Design time-domain statistics. The comparative statistics show that the simulations are in good agreement with the experiments. Guardrail tension data and cable tension data are presented from the LS-DYNA simulations. Results show that the guardrail was close to its tension yield point when impacted at an initial velocity of 35 km/h.