## 2 Case Study: The Acuto Field Laboratory  
The Acuto field laboratory is located in the westernmost sector of an abandoned limestone quarry (Prenestina quarry) within the Municipality of Acuto (Central Italy) (Figure 2). It was designed and instrumented starting from November 2015 in the framework of multiple experimental activities managed by the CERI of Sapienza University of Rome. This natural test-site aims to investigate the ability of an integrated multiparametric monitoring system to decipher the role of environmental and anthropic stresses in determining the worsening of rock mass stability. The abandoned quarry, which is a few hundred meters NE from Acuto, is found on a monoclinic SW-dipping carbonate slope, where a succession of Meso-Cenozoic limestones is affected by NW-SE striking normal faults with offsets up to 10 m [46]. The monitoring system consists of several geotechnical and geophysical devices and was installed on the vertical rock wall outcropping in the western sector of the abandoned quarry. After a preliminary surveying stage and geomechanical characterization, a potentially unstable 20 m\({}^{3}\) rock block was identified as the main target of monitoring activities [47]. This element was selected due to its severe fracturing degree and the presence of a rear discontinuity detaching the rock block from the quarry wall behind, thus predisposing this volume toward instability (Figure 2a). The monitoring system consists of (i) one temperature probe for rock mass temperature, (ii) six strain gauges installed in correspondence with microcracks, (iii) four extensometers installed on open fractures, and (iv) two fully equipped weather stations. The system is cable-connected to a Campbell Scientific CR1000 data logger collecting data with a 1 min sampling rate. Apart from the permanently installed devices on the rock block, the spectrum of monitoring activities at the Acuto field laboratory was enriched by several experimental activities carried out over the years. These activities were designed to study the effect of preparatory factors on rock slope instabilities and test novel methodologies for the investigation of progressive damaging processes in jointed rock masses [48; 49; 50]. From 2018 to 2019, an MS monitoring array composed of several one-component micro-accelerometers was installed on the rock block and  
Figure 2: View of the monitored jointed rock block at the Acuto field laboratory ([[https://www.dst.uniroma1.it/en/structures/laboratories/NaturalLaboratoryAcuto](https://www.dst.uniroma1.it/en/structures/laboratories/NaturalLaboratoryAcuto)]([https://www.dst.uniroma1.it/en/structures/laboratories/NaturalLaboratoryAcuto](https://www.dst.uniroma1.it/en/structures/laboratories/NaturalLaboratoryAcuto))) along with the stereographic projection (equal-angle lower hemisphere) of pole density distributions and planes of the four main discontinuity sets (SF: slope face) (**a**). The two boxes help to better visualize the different volumes involved by the configurations adopted during the first (I, red box) and the second monitoring campaign (II, green box). Between February and May 2018, six micro-accelerometers (1–6) were deployed along a linear alignment specifically designed to mark the transition from the stable rock mass to the unstable rock block (**b**). The second monitoring campaign (November 2018–October 2019) was conducted by installing six micro-accelerometers (1–6) in a “composite” double three-component configuration (**c**). the contiguous rock wall. This system perfectly integrated with the already existing one, providing interesting insights into the dynamic and deformational response of the studied rock block in response to continuous and transient environmental stresses [18; 23; 24]. The monitoring array was composed of six one-component piezoelectric micro-accelerometers (Bruel & Kjaer type 8344).