Abstract
Since ECE R-66, mechanical strength of coach structures, was introduced as standard in Europe, a big improvement in passive safety has been seen. In 1987, when ECE R-66 was published, the use of seat belts was not mandatory and coaches were not equipped with these devices. Since
October 1997, the situation has changed because directive 96/38/CE has made mandatory the use of seat belts in coaches. With this directive there is now a new factor in the interior of a coach, different from the original one studied during the drafting of ECE R-66. In considering this new factor, some questions have appeared regarding improvements in the safety of these vehicles: how will the effect of the mass of the belted occupants over the superstructure affect the survival space during a roll-over accident? And moreover, does the seat belt give protection during a roll-over accident?
This article focuses on two aspects: structure resistance and passenger injuries. To evaluate the structure resistance, the distance between the pillar and the survival space will be the main variable; furthermore, the evolution of the energy of the test will be monitored. To evaluate the passenger injuries, pelvis acceleration and head acceleration will be the main variables. The rollover test defined in the ECE R-66 will be simulated with different occupant situations: unbelted occupants, lap belted occupants and three point belted occupants.