Experimental evidences of thermo-mechanical induced effects on jointed rock masses through infrared thermography and stress-strain monitoring

The Mediterranean area is subjected to considerable daily and seasonal thermal variations due to intense solar radiation. This effect influences the long-term behaviour of jointed rock masses, operating as thermal fatigue process and acting as a preparatory factor for rock failures. In order to quantify intensity and influence of thermo-mechanical effects on rock slope stability, a multi-parametric monitoring is operative in an abandoned limestone quarry at Acuto (central Italy) by remote (i.e. IR Thermography) and direct (i.e. thermocouple and strain sensors) sensing techniques. The monitoring system has been focused on an intensely jointed rock block. Several joints bound a prismatic-shaped volume, isolate it from the rock wall behind and cause its protrusion respect to the quarry wall so increasing proneness to fall and toppling. Preliminary data analyses highlight the cyclical deformative response of block to thermal forcing, revealing the effect of sun radiation and exposure because of the heating of the rock surface.