Carolina Segui, Esperança Tauler, Tomasz Hueckel, Manolis Veveakis

Thermal triaxial tests were carried out on remolded material of core samples of the shear zone of a deep-seated landslide, the El Forn landslide (Andorra). With the thermal triaxial tests, we have obtained thermal and rate sensitivi- ties of the material outside and inside the shear band. Moreover, micro-scale tests were carried out, such as XRPD, SEM-EDS, MicroCT, and plasticity index. The results show that the material inside the shear band has higher thermal sensitivity than outside the shear band. These results are related to the material’s fabric, porosity, and plasticity index. The rate sensitivity value is the same for the samples outside and inside the shear band, being able to correlate the rate sensitivity with the mineralogy content of the ma- terial. This study, thus, aims to understand the mechanical behavior of the material within a shear zone by correlating the thermal and rate sensitivity with the microstructure and mineral phases present in the material.