The connection between rock mechanics and the world of mines and quarries is evident, as most primary resources needed by industry are concentrated in mineral deposits, often in rock masses. This can be seen at all levels, from the design phase to running the extraction process and providing protection to workers. Equally important is the optimization of the process, to enhance cost-effectiveness and reduce impact on the environment. A rock mass is characterized by blocks identified by discontinuities. It is, thus, useful to exploit the fragmented nature of the rock mass to optimize the excavation process. In the case of dimension stone quarries, the role of rock mechanics is even more evident as the precise and accurate knowledge of the features of the target rock mass is a fundamental requirement. The assessment of the block size distribution influences the feasibility of the operation and allows to identify a suitable and advantageous size for the extraction process. The orientation of the joints directly impacts the direction of excavation and the geometry of the fronts in terms of stability and productivity. The present work focuses on assessing the geometrical properties of a rock mass, namely block size and shape, aimed at optimizing the design and extraction process of a dimension stone quarry. For this purpose, a novel application of the In situ Block Size Distribution (IBSD) and shape distribution approach to dimension stones quarries is discussed. A robust statistical analysis of the rock mass geometric properties is coupled with the IBSD approach to block size and a new shape classification system. A set of synthetic data will then be employed to present a general case study, while a suitable case study is presented, describing the context of a real marble quarry (Lorgino quarry, Crevoladossola, Piemonte, Northern Italy) where the discussed approach could yield positive results.

The assessment of rock outcrops’ predisposition to the main possible kinematisms represents the preliminary step of stability analysis: Markland’s tests for sliding and toppling constitute a milestone due to the ease of use and interpretation of results. Orientation and friction angles of the main discontinuity sets and orientation of rock faces are required as input to perform the test on a stereonet graphically. However, for natural outcrops, the orientation of rock faces could vary significantly, and the test should be performed assuming all the representative ones. To speed up this process, the authors set up an automatic procedure based on the GIS environment working principles and developed it in Matlab language. Main discontinuity sets orientation and relative friction angles, along with slope and aspect data representing the rockface orientation of the considered outcrop, are the input data. The slope and aspect data are in GeoTIFF format, the most common format for georeferenced raster files employed in a GIS environment. The Matlab code performs Markland’s tests for planar and wedge sliding and flexural toppling, considering all the possible sets or intersections of sets, and provides the output with the same extent and georeferencing of the input data. The outputs are a series of GeoTIFF raster files describing the result for each kinematism separately and globally, which can be imported directly into GIS. The global results can also be used to map source areas for 3D rockfall numerical simulations. The code was validated through a case study by comparing its results with those obtained by performing the conventional tests singularly on a number of significant rock faces. The results obtained in the case study show that the algorithm produces reliable results consistent with those provided by traditional methods.

In dealing with rockfall risk mitigation, a proper assessment of the phenomenon is the key to correctly and precisely managing its possible consequences. In doing so, numerical simulations are an unavoidable step of the assessment process. The proper description of the slope and the falling rock is paramount. Thus, it is highly relevant to accurately assess block size and shape. Block size directly defines the kinetic energy involved in the phenomenon, whilst shape directly influences its trajectory. Tools to properly assess both block size and shape are available, either in analytical form or relying upon Discrete Fracture Network (DFN) models. However, at present, no concrete demonstration of the equivalence of these two methods is provided in the literature. Moreover, block size and shape are always treated separately, while it is likely that a relationship of some sort exists between the two as they derive from the same features of the rock mass (i.e., the 3D geometry of its discontinuities). This paper presents a comprehensive study concerning (1) the comparison between DFN and analytical approaches and (2) the existence and quantification of a shape–size correlation. A modeling campaign consisting of 20 different geometrical structures is performed with both methods, with the aim of obtaining In Situ Block Size Distributions and Shape Distributions. Although the DFN and the analytical approach have different advantages and disadvantages, they have proved to be comparable in terms of results. Both methods identify the existence of a correlation between shape and size of the blocks: the shape distribution changes with reference to block size. This result points out the importance of implementing shape distribution in rockfall numerical simulations. Finally, a suitable case study from the literature has been selected to test the applicability and usefulness of the new findings for the design of rockfall barriers.

This paper presents an analysis of the debris flow phenomena in the Rio Inferno watershed (Municipality of Cesana Torinese, Western Alps, Italy). The annual frequency and magnitude of these events have caused significant damage to the viability of the historic Chaberton Military Road, which is now closed to transit. This study delved into the processes governing debris flows in the Rio Inferno watershed through detailed geomorphological analysis, an unmanned aerial vehicle (UAV) photogrammetric survey, and the elaboration of rainfall data from the nearby weather monitoring stations. The Hydrologic Engineering Center’s River Analysis System (HEC-RAS) code was used to simulate debris flow events considering critical precipitations associated with return periods of 20, 50, 100, and 200 years, based on the highly detailed topographical model obtained by means of photogrammetry. The paper highlights the importance of studying debris flow phenomena to implement effective risk mitigation and management strategies, especially in the context of climate change and the increased vulnerability of mountain territories.