Ricerc@Sapienza

Most faults and rockslides exhibit time-dependent deformation known as brittle creep which has been characterized through laboratory experiments in the literature on several lithologies. These experiments highlighted the strong influence of lithology on fault creep behaviour as well as on rates of geomorphic processes in landscape evolution. Creep processes in rock masses have been recently demonstrated to be very important factors for the development of instabilities at slope scale over a long- to very-long-time interval.
The aim of this project is to characterize the creep behaviour of rocks and evaluate influence and scale-dependency of this process on both earthquakes and landslides mechanics, in order to assess their hazards. A scale-convergence is proposed by selecting two case studies represented by a local fault (the Alto Tiberina Fault - ATF) and a giant-landslide shear surface (related to the Saidmarreh landslide). The ATF is, one of the largest extensional fault system in Central Italy (60 km long) active in the Quaternary while the Saidmarreh landslide is the largest known subaerial non-volcanic landslide on Earth.
Creep tests will be performed on rocks representative for the two case studies by using a biaxial apparatus, BRAVA within a pressure vessel in order to simulate a true-triaxial stress field. Two types of experiments will be run: 1) constant displacement rate experiments to determine slip zone strength, and 2) creep experiments to evaluate the evolution of slip behavior (i.e. seismic or aseismic). Our unique and innovative laboratory results will be compared to the boundary conditions observed in the study areas and will help to model the slip behaviour and its triggering effects of the two case studies. These data and models will have a considerable impact on the scientific community due to both the unicity of the acquired dataset and the relevance of the proposed case studies.