A new proposal to assess shear fatigue resistance of asphalt pavement interfaces

The degree of adherence between two bituminous layers can be assessed from shear tests carried out at constant displacement speed, which allow the shear strength and stiffness of the interface to be obtained, being usual to specify a minimum strength. But stronger bonds will be more stressed, which could negatively affect their fatigue behaviour. In this work, the shear fatigue behaviour of two interfaces of different stiffness has been analysed, based on a cyclic compression test, performed at controlled stress, using the test device B described in the NLT-382 standard, included in the draft of the European pre-norm prEN 12697-48. From these tests, fatigue laws for each type of interface have been obtained. These laws, combined with a calculation method developed by the authors, have made it possible to obtain the number of cycles that each interface would withstand, under certain load hypotheses.

Automated summary

In this study, the shear fatigue behavior of two interfaces with different stiffness was analyzed through cyclic compression tests. Fatigue laws for each type of interface were obtained, and by combining these laws with a calculation method, it was possible to estimate the number of cycles each interface could withstand under certain load assumptions.