Numerical experimental study of soil influence and interaction with road safety barrier

Road safety studies the protection of vehicle passengers in the event of an accident, trying to avoid or limit damages to the passengers themselves as much as possible. The performances of road safety barriers are assessed through full-scale crash tests in order determine their level of safety and the space needed to contain and redirect an errant vehicle. The importance of simulations goes through every component of the barrier, the soil plays a key role in the behaviour of the device and experimental/numerical corre- lation is crucial for the quality of the results. The goal of this thesis is to develop a FE model of soil which could be adapted according to the results from the experimental test in order to ease and improve the design of new products. Two experimental campaigns are studied, in order to evaluate the in uence of soil composition and embedding depth. The test results provided a basis to develop a numerical model able to achieve a satisfactory correlation with the tests.Despite the good correlation, the great variability of soil characteristics, caused by environmental conditions, has induced to abandon the possibility to characterize the soil aggregate as a material itself. A computationally e cient model has been developed and adapted to the three levels of soil resistance identi ed by the normative EN1317 proposals, this model has been successfully used to evaluate the in uence of di erent soil grades in a full scale crash simulation both in terms of de ection and in terms of severity indexes.