Abstract
Keywords:
roadside safety, road safety barriers, explicit computational simulations, finite element method, LS-DYNA, crash test.
Abstract
One of the major problems in road transportation is to assure adequate safety level for road users. To maintain and improve road safety, it is often necessary to install certain devices on the road that are intended to restrain vehicles and pedestrians from entering dangerous areas. The road safety barriers, designed according to the European EN 1317 standard, provide certain levels of vehicle containment, properly redirect errant vehicles back on the road and provide guidance for pedestrians and other road users. Practical observations of currently installed systems indicate that their design is inappropriate, since vehicles often overrun the restraint system or the level of vehicle decelerations is unacceptable. The purpose of this research is to define appropriate design changes to lower the impact severity and to secure the integrity of the restraint system during vehicle impact. The impact severity and stiffness of the new design have been evaluated with the explicit dynamic nonlinear elasto-plastic analysis of a full-scale computational model of the road restraint system within the framework of the finite element method with LS-DYNA code. The results of the computational model were then compared with real crash test data. Comparison of computational and experimental results proved the correctness of the computational model. The tests have also shown that the currently used road restraint system is indeed too stiff and that new design assures controllable deformation and higher crash energy absorption which in turn decreases the decelerations of an impact vehicle and consequently increases the safety of vehicle passengers.