GNGTS 2024 - Atti del 42° Convegno Nazionale

Session 1.2 GNGTS 2024 the instable sector of SDF (Fig.1). Triaxial direct-shear tests, via a purpose-built housing rig, equipped with two Piezo-Electric Transducers on 50 x 20 mm rectangular slabs at 5, 10 and 15 MPa both in dry and wet conditons were carried out to explore the coupled evoluton of the frictonal and seismic propertes. Confning pressure and saturaton have afected the fricton coefcient. Rate and state fricton parameters and fricton coefcient are controlled by changing sliding velocity (Alcock et al., submited). Microearthquakes recorded (Acoustc Emissions) and their key atributes, such amplitude, frequency and duraton and their evoluton confrm the relaton to sliding velocity, confnement and porosity. Post mortem SEM analysis has revealed the impact that textural features on the evoluton of fracture damage and their control on the frictonal propertes. These fndings have been related to the feld scale slip dilaton analysis providing quanttatve support for the identfcaton of structurally weak zones across the SDF and constraint the mechanical behaviour of the fractured zones prone to instability. Fig. 1 - Slip tendency fracture map of the Sciara del Fuoco collapse scarp with sample site locatons (A) of Vallone del Monaco (VM), Semaforo Labronzo (SL), Serro Adorno (SA), Ginostra (G) and Vancori (V) in relaton to the NE/SW directon of σ1 aligned with the zone of weakness across the edifce. Rose diagrams of Td (B) and Ts (C).