Earthquake Damage Scenario in Visp (Switzerland) : From Active Fault to Building Damage

We present a damage scenario based on multidisciplinary study which covers the key elements of the earthquakerisk chain in Visp. Full dynamic rupture simulations are performed using heterogeneous initial distributions,statistically compatible to the database of kinematic inversion results of past earthquakes. The fault is embeddedin the 3D velocity model of the area, which is based on an extensive ambient noise measurement campaign. Inorder to assess the risk in the city of Visp, the buildings were classified based on the screening survey of thebuilding stock. The seismic behavior of each class is described by the mean of fragility curves, partly developedby analytical, numerical and experimental investigations and partly based on existing method

Multimethodological study of non-linear strain effects induced by thermal stresses on jointed rock masses

A multimethodological method based on environmental, stress–strain, microseismic, and ambient seismic noise monitoring is here presented, with a view to identifying non-linearity of thermally-induced deformation of jointed rock masses at different dimensional scales. Rock masses experience non-negligible deformation cycles due to the continuous fluctuations of their surficial temperatures. However, the interpretation of such strain effects, in terms of the ratio between elastic and inelastic percentages, is still debated. In particular, the relation between microseismic emissions, considered as primary indicators of crack-growth related energy release, and resonant frequencies fluctuations of rock structures, witnesses of the thermally-induced effect at the macro- or structure-scale, have not been yet studied within a coupled framework. The combination of different approaches able to investigate the behavior of rock masses from micro- to macro-scale, then from fracture-scale to joint-isolated rock blocks up to rock structures, could provide new insights and perspectives on the effects related to shallow thermal stresses fluctuations. This paper presents the preliminary outcomes from two case studies, the Acuto experimental test-site (Italy) and the Wied Il-Mielaħ sea arch (Malta), where multiparametric monitoring surveys were conducted and are still ongoing, aiming at the assessment of the cause-to-effect relation between near-surface thermal stresses and induced strains. Data analysis was carried out following different approaches, with a particular emphasis on the Acuto test-site dataset recorded so far, allowing to establish a well-constrained correlation among temperature fluctuations and rock mass deformation both at the daily and seasonal scale