The use of 3D slope stability models for assessing risk and opportunity across various time horizons from the life of mine, five-year (5YP), two-year (2YP) and quarterly or three-month (3MP) mine plans is becoming common practice. The goal is to improve mine design reliability, and as an industry, achieve digital twins for mining and slope stability. These improvements are facilitated by faster computing and user-friendly 3D slope stability software as well as in-creasing monitoring instrumentation deployment in open pit mines. This paper investigates the use of Hu coefficients for simulating pore pressures relative to pre-defined phreatic surfaces or groundwater tables to facilitate rapid updates to 3D slope stability models based on updated pore pressure data obtained from a network of vibrating wire piezometers (VWPs). It also dis-cusses pore pressure sensitivity checks for risk management, and the benefits and limitations of this approach.

In 2010 a process was started to stablish international standards on geotechnical instrumentation under the ISO umbrella. General concepts of these standards were published in 2015, the first part on extensometers in 2016, the inclinometers document in 2017, total pressure cells and piezometers were published in 2020 . All these documents have been published in English and French all over the world. In Europe these documents have been published under EN_ISO 18674. Part 8 on the use of load cells to measure load is in the last steps of the approval process and probably Will be published this 2023. The aim of the paper is to show the development and specific role of these standards on the use of geotechnical instrumentation.

The Mediterranean region has witnessed major infrastructure projects in recent decades, with multiple tunnels usually being constructed using NATM (New Austrian Tunneling Method). The essence of this method lies in continuous observation of deformations and geological assessment, allowing for optimization of the tunnel support system. However, the presence of BIM (Block-in-Matrix) rocks implies significant challenges to application of NATM. The BIM rock exhibits chaotic, heterogeneous, and often highly unpredictable geological structure. This makes it impossible to assess the quality of the rock mass using conventional categorization methodologies such as RMR (Rock Mass Rating) or GSI (Geological Strength Index). The challenges of tunneling in BIM rock were encountered in 3,6 km twin tube tunnel Golubinja, which is currently under construction in Bosnia and Herzegovina. Geological profile was initially assumed to consist of medium strong to weak, moderately to highly weathered shale, siltstone and sandstone of Jurassic age. During the construction phase, a significant discrepancy between the predicted geology and the actual conditions was encountered. The actual conditions were characterized by the presence of ophiolite mélange and ophiolithic crust sheets formations leading to a BIM type of material in which the matrix was formed of siliciclastic strata (graphitic phyllite) and blocks were formed of sedimentary and metamorphic rock. The designed short axis distance between the twin tunnels of 25 m led to a strong interaction between the tubes and presented an insurmountable obstacle for tunnel construction. Issues such as collapse of the primary lining and general instability were observed along the extensive sections of the tunnel. The reevaluation of the geological profile, increasing length of the axis distance between the tubes, and implementation of secondary lining as part of the support systems were carried out in order to enable buildability of the tunnel for given conditions. This paper presents key aspects of Golubinja tunnel construction including design approaches and remediation measures to overcome challenging BIM rock conditions.

This work focuses on obtaining and updating an inventory map of active landslides in the region of Sierra de Cartagena-La Union (Spain), a mountainous mining area in southeast Spain, by integrating space-borne InSAR and airborne LiDAR techniques. Ascending and descending Sentinel-1 InSAR datasets were processed to obtain LOS displacements. Moreover, open-access, and non-customized LiDAR point clouds were processed to analyze surface changes and movements. Then, active deformation areas (ADA) maps were semi-automatically derived from the InSAR and LiDAR results by using ADATool. The influence of rainfall was analyzed in detail by means of InSAR time series. The results not only highlight the effectiveness of these two remote sensing techniques (i.e. InSAR and LiDAR) to acquire inventory maps of active landslides in mining zones, but also emphasize the key role of rainfall as an important trigger for landslides.

The rains registered in Leon (Spain) during December 2019 created several problems on the railway platform: Line 130 Venta de Baños-Gijon, Section: La Robla - La Pola de Gordon. Damages were at the P.K. 26+700, where rockfalls happened coming from the rocky front located above the railway track. The rocks that come from the top reached the railway platform. A huge rock of approximately 50 t has exceeded the railway and has stopped on the edge of the town Puente de Alba. There are also some rocks, weighing slightly less than 10 t, which have remained next to the track. A statistical analysis of rockfall was done, to define locations of the mitigation measures and evaluated other practical solutions. Finally choosing the installation of the following systems: Rockfall drape system with TECCO® G65/3 high tensile-strength steel mesh, with horizontal reinforcement ropes and Rockfall barrier, 8 m high and energy absorption capacity of 8,000 kJ.

Wire meshes employed in secured drapery systems are constantly exposed to atmospheric corro-sion, resulting in diminished durability. The durability depends on the aggressiveness of the envi-ronment, unique to each location, and the protection of the wire, which is often poorly defined in projects. The applicable regulations include a classification of different environments (C2, C3, C4, C5, CX) based on their corrosivity levels. The class of environment serves as a technical character-istic to specify the necessary wire protection to ensure the stipulated service life. Steel wire prod-ucts typically have two types of protection: galvanic coatings, delivering electrochemical safeguard, and organic coatings, which create a physical barrier from oxygen. This article examines the perti-nent regulations, analyzing durability tests such as salt spray test and Kesternich test, different alloy alternatives, the projected service life for each environmental classification, and a case history re-garding this topic.

Many excavated weathered rocks have good initial stability but lose geomechanical properties until have behaviors similar to some soils, causing collapse of shoring. This is an analysis of different temporary shoring of excavations and their effectiveness reviewed with monitoring. The analysis reveals the relationship between excavation height and deformations. Likewise, it is observed that the incidence of the excavation stages and geometries has a greater impact on the deformations than the stiffness of the applied support.

Potash mining in Germany is thriving since more than hundred years, however reserves are limited, and many deposits will reach the end of its lifespan within the next decades. A new mining concept has been established to increase the lifespan of the mines and maximize the extraction rate of conventional mined potash deposits. The concept of secondary conventional mining utilizes the reduction of the dimensions of pillars to gain additional high quality crude salt. The supporting effect of the pillars is compensated by backfilling of the mined excavations, supported by a comprehensive long-term monitoring concept. The process of maximizing extraction rate with secondary conventional mining starts with mining of the pillar edges. The developed cavity is backfilled with rock salt (or residual material from the manufacturing). A backfilling grade of 90 % is aspired. In a next step the remaining pillar is excavated, leaving two small pillars at each end, which serve as short-term roof support until the remaining excavation is backfilled. With this procedure pillar after pillar are excavated until the whole mining area is backfilled. In preparation of this mining process rock mechanical investigation is done to proof a save mining process. It contains of a numerical modelling and an observation program. The numerical modelling bases on precise rock mechanical 2D and 3D models. The calculation evaluates possible hazards like pillar or field collapses and predicts the expected rock mechanical behavior. Then latter covers the mining induced effects to convergence and their impacts to barrier integrity as well as surface subsidence. The results show that the stresses in the barriers doesn’t endanger their integrity and the predicted surface subsidence is compatible with their normal use too. Bases on these results a monitoring concept is developed to observe the real rock behavior. It includes the development of convergence in the mining field, the released energy during and after the second mining process as well as the observation of surface subsidence – all bases on advanced observation methods. The comparison of the monitored results with the numerical prediction supplies a robust basis for a save mining process.

A massive rockfall event took place at the very entrance of a steep and large Đerdap Gorge on the Danube River in Eastern Serbia on 12-13^th of December 1974. Detailed engineering-geological examination of the site was undertaken at the time, but the event was never fully reconstructed. With the ascent of new surveying and monitoring technologies, and their greater availability in recent years it became possible to revisit such historical events and completely back-analyze them. Otherwise, the Gorge itself is rather active and constantly hosts minor rockfalls and other instabilities. An important international route passes along its base, where despite preventive and protective measures it remains highly exposed to rockfalls, whereas the river, i.e., the artificial lake itself, and the downstream hydropower plant and dam could be endangered by massive events, like in the 1974 when one third of the Danube River profile was dammed. The said event was triggered in an abandoned limestone quarry named Joc, arguably by several preconditioning factors: draw-down effect due to filling of the Đerdap lake that took place in 1972-1973, adversely oriented caverns subject to progressive failure, disturbed rock by heavy blasting in the past, lubrication along the adversely oriented joint set. In spring 2023, a field campaign targeted at ground surface mapping of the wider area was undertaken using advanced geodetic equipment, comprising of UAV Wintera and Mobile LiDAR scanner Leica Pegasus. The objective was to re-map the entire north face and surrounding topography and reconstruct the rockfall. The resulting point cloud depicts an irregularly jointed rock mass, likely disturbed by heavy blasting. The location of the source area was determined from the available field photos, and suggests that one large feature, placed amidst the slope, about 100 m above the road level was detached. It has been severely deformed and fragmented along the runout, so it has been transformed into a pile of rubble with large sized boulders. Total volume was estimated to 250,000 m³. The reconstruction was performed using a variety of tools, starting from simple 2D and 3D models that implement friction cone theory, to robust 3D models that consider complex geometry of collapsed material and detailed ground relief. Expectedly, robust models were more successful in reconstruction of the event, which was validated on the basis of known runout reach and debris height.

Urban sites in highlands or associated with rocky areas are common, giving them an admirable landscape richness and constituting a relevant part of their identity. However, this uniqueness is closely related to the risk posed by the degradation of rock formations, which generally results in the falling of blocks or, in the most severe cases, in landslides. Only in the past year, this phenomenon has occurred in locations such as Mijas, Almogía or Ardales in Spain. This article takes the example of Alcalá la Real (Jaén) to present a process and analysis model to quantify the geological risk factors in scenarios of rockfalls such as the one that took place in this town, which enables the assessment of the possible actions to be carried out with the aim of reducing these risks. It is important to remark the fact that, in most cases, one of the main premises is that the action should not have a major impact on the landscape. The underlying cause of the study carried out in the aforementioned municipality of Alcalá la Real was the fall of a large block on Calle Utrilla on a Sunday in summertime, as well as the risk of a further landslide affecting the pathways and houses located in the lower part of the hill. Once the block had detached, its fall by gravity put at risk the houses located at a distance of 125 ml. on a slope with a difference in height of 43 metres. The detached block had a volume of about 72 m³ and an estimated weight of 190 tons. The slope from which this block detached is formed by a level of bioclastic calcarenites supported by soft sandstones, sands and wall clays. The state of the outcrop before the instability occurred was conditioned by the strength of the material supporting the calcarenite levels and the fracturing system of the latter. The study considered several actions to be undertaken given the risk that more blocks could detach, quantifying and zoning the risks for each of the proposed actions.

The natural and cut slopes of a segment of the Dharasu-Uttarkashi Roadway (NH-108), located in the Lesser Himalayan Zone in India, have been studied adopting a multi-parametric integrated approach in terms of (1) distribution of magnitude of natural slope (2) engineering geological properties of intact rocks and rock masses, (3) kinematic analysis of slopes, (4) documentation of existing slope failures (5) rock- microstructural implications, (6) multiple geomechanical classifcation of slopes and (6) implications of active tectonics as deciphered from Neotectonic indices. Assessment of stability of slopes based on the combined study of the above parameters has been performed for twelve locations (L1−L12) on the road-cut sections where the slopes mostly have not yet failed. Magnitude of natural slopes overlooking the road section attains peak slope class of 41°−50°. Kinematic analysis characterizes the intact slopes in the above locations to possess conditions of wedge and toppling modes of failure, either in single or as combined. Existing failed slopes conform to combinations of planar, wedge, toppling and shallow circular failures. Rock microstructural study reveals development of strong shear-strength-weakening foliation anisotropy in the phyllites and schistose quartzites of the slopes that evidently serve as avenues of groundwater percolation and seepage and can promote failure along water soaked foliation planes that ‘day-light’ on the road-cut slopes at locations L1, L8 L9 and L10. Based on Geomechanical classifcation systems applied to slopes including Continuous Slope Mass Rating, Q-Slope and Hazard Index, new stability charts have been developed that classify the slopes at each location to be one of the three types: severely unstable, unstable or stable. Based on the new stability charts, road-cut slopes at all twelve locations were found to be unstable and slopes at three locations−L7, L8 and L10 were observed to be severely unstable, particularly hazardous and require immediate mitigation. From the erosional landscape of the study area, using several geomorphometric elements including ruggedness number (R_n), ratio of valley floor-width to valley-height, (V_f), stream length gradient index (S_L) and Hypsometric integral (H_i), an index of neotectonic activity (I_at) over the study area is obtained with an estimated value of 1.50 that indicates high neotectonic activity. Such high value of neotectonic index correlates with the high recent seismicity events documented from the zone containing the study area. Corresponding high neotectonic activity is expected to create steeper slopes due to deeper incisions and would potentially trigger failures in some of the currently stable slopes in the area.

Slope stability analysis is crucial for transportation projects in hilly areas, especially for road or tunnel portals. Various methods exist to assess slope instability, such as field-based, limit equilibrium, Numerical, and rock fall simulation. Among these, the field-based Slope Mass Rating (SMR) method is popular for initial assessments. In this study, a Windows-based Python application was developed to calculate SMR efficiently. The app quickly evaluates slope instability using provided data and allows users to input direct Rock Quality Designation (RQD) or estimate it based on joint spacing. It automatically calculates F1, F2, and F3 factors for all joints and identifies formed wedges due to joint interactions. The app generates detailed reports including joint attributes and ratings, aiding in slope stability interpretation. This user-friendly tool enhances slope stability analysis for project planning and generates technical reports for better project understanding.

Waste dump failures in coal mining pose significant safety risks, necessitating detailed post-failure studies alongside pre-failure deformation study. The post-failure studies evaluate the mobility of the failing mass, measured by parameters like runout length and width (i.e., runout characteristics). The understanding of the mobility of failing mass will help design a buffer zone around an overburden dump to restrict worker and machinery movement. This study, using a laboratory-scale debris flow flume, explores the effect of the composition of overburden dump on runout characteristics and the shape of debris flow fan. The findings of the experimental investigation suggest that while changes in relative proportion of fines and coarse particles (F/C ratio) affect both runout length and width, the effect on the aspect ratio may not show a straight forward pattern. The complex changes in aspect ratio imply that the overall shape of the debris flow fan may not be solely determined by the F/C ratio.

Elastic properties of rocks like Young’s modulus and compressional P-wave velocity are vital for understanding their stress-strain response in mining and rock engineering applications. Traditional methods for determining these properties involve labor-intensive, expensive and time-consuming. To address these challenges, this study proposes a novel predictive method. It utilizes a multi-layer perceptron feed forward neural network (MLP-FFNN) trained on grinding characteristics of ball mill to predict Young’s modulus and compressional P-wave velocity in sedimentary rocks. Laboratory experiments on limestone and dolomite samples generated extensive data, enabling development of prediction models using the proposed MLP-FFNN. The developed models demonstrate high predictive accuracy (R values: 0.952 for E, 0.987 for Vp) in training and good generalization (0.866 for E, 0.9707 for Vp) in testing, along with low Root Mean Squared Error (RMSE) values. These findings underscore the efficacy of neural network models in predicting E and Vp from grinding characteristics of ball mill.

Extraction of coal is done by both opencast and underground method of workings. The amount of overburden removal has increased significantly as the share of opencast coal mining has increased to ensure maximum recovery and greater depths. The accumulation of the removed overburden material as dumps at greater heights for the minimum ground cover area is an important task in the opencast mines due to which the dumps tend to fail. A dump failure can pause mining operations, endanger personnel and damage equipment. In some cases, due to lack of dumping space, the overburden dumps are laid above the underground excavations. The stability of the dumps over the old underground workings is a difficult task because of the stresses that are already developed due to the underground excavation. Therefore, it is paramount to study the stability of the slopes in this zone particularly when there was an old inaccessible extraction present within this zone. In this article, the prediction of stability of overburden dumps above the underground workings are studied by means of underground longwall working dimensions. A two-dimensional finite element analysis method is used in predicting the stability of overburden dump using RS2 software of Rocscience. Strength Reduction Technique is used for determining the factor of safety (FoS) of the overburden dump. From the modelling studies, it is summarized that the stability of the overburden dumps is being affected due to the presence of underground excavation with a vertical deformation of 0.0564m (56.4mm) for the critical strength reduction factor 1.12.

The Grassy Mountain mining project owned by Paramount Gold Nevada Corp. in the state of Oregon, USA has been developed for a Cut and Fill underground mining methodology with cemented backfill (CRF) operation. The present study analyzes the main variables involved in the manufacture and subsequent performance of cemented backfill, through a sampling process involving 12 CRF specimens prepared and tested by MetaRock Lab under the supervision of GMS, in order to obtain the UCS strength values of each one. Thus, 6 CRF specimens with 5% cement and 6 specimens with 7% cement were prepared, which in turn were subdivided into a curing time of 14 and 28 days. From the results of the UCS tests, the variables of cement percentage, sample density and days of curing are directly related to the strength of the CRF, obtaining better performances as these values increase. Finally, based on the benchmarking study, the performance of the CRF samples, according to the mix developed and proposed by GMS for the Grassy Mountain project, is within the expected range. The values for resistance, which is the main indicator to be highlighted, are in accordance with what would be expected according to the characteristics of the mixture, obtaining a maximum resistance of 6.14 MPa.

Due to rapid and extreme climate changes, in mountain and hilly regions infrastructures and people are more often treathened by rockfalls events. Falling boulders can have extremely high speeds, and these events involve a complex pattern of movement (e.g. detachment, fall, rolling, sliding, bouncing, etc) of one or more rock fragments. Rockfall Protection Embankments (RPE) reinforced with geosynthetics proved to be a safe measure for protecting people, structures and infrastructures from rockfall events, designed to absorb even very high impact energy (up to 30,000 kJ). RPEs can be constructed in various shapes and sizes, with different reinforcements (geogrids, geotextiles, geostrips, steel wire meshes, etc.) and facing materials (wrap-around, gabions, tires, etc.). The vast majority of existing RPE structures have been designed with basic approaches, considering dynamics only to a minor extent. The Authors have then developed a new analytical design method which consider the effect of all the variables playing a role in the resistance to penetration on the uphill face and the resistance to extrusion on the downhill face, in order to finally compute approximate yet consistent values of the penetration depth and of the extrusion length; hence the designer can quickly try different solutions and finally select the best combination of design variables which afford to respect all design limits and Factors of Safety. To the Authors’ knowledge, at present this is the only design method for RPEs which allows to take into account all the parameters contributing to the penetration and extrusion resistance, including the type and properties of geosynthetics, the layout and spacing of reinforcement in longitudinal and transversal direction of embankment, the type of facing, the properties of the fill and the geometry of the embankment. A back analysis of full scale tests is used to validate the presented design method.

Underground structures such as tunnels play a prominent role in modern-age infrastructures. Most of the tunnels are constructed in hilly regions as they provide the shortest motorable link between two places in complex geological conditions. However, earthquakes such as the 1923 Great Kanto earthquake, the 1995 Kobe earthquake, the 1999 Chi-Chi earthquake, the 2004 Mid-Niigata Prefecture Earthquake, the 2008 Wenchuan earthquake, and many more earthquakes damaged rock tunnels to various extents. Poor ground conditions are one of the major reasons for damage to rock tunnels during earthquakes. To investigate and understand the ground conditions that played a major role in damaging tunnels, geological/ground data on damaged tunnel sites is necessary. So, in this study to understand the damage response of rock tunnels, the data related to rock mass is collected from 236 tunnel sites, that are damaged due to 26 different earthquakes all over the world. This study provides an emphasis on the impact of rock strata (Hard/Soft rock) on seismic damage to tunnels based on the largest database of post-seismic damage database of rock tunnels (PSDDT). The impact of damage on rock tunnels for conditions like rock tunnels that passed through fault fracture zones or rock tunnels residing at the interface of soft and hard rock are also elaborated from various damage cases in PSDDT. The Rock Mass Rating (RMR) system is found to be a major parameter in this study. The RMR for a few of the rock tunnels in the created PSDDT is obtained directly from a few literature sources. Immense efforts like utilizing descriptions of geological/ground data of the site, few empirical relationships are made to obtain RMR for the damaged rock tunnel sites if they are not available directly from literature reports. It was observed that the poor and very poor rock classes of RMR have a significant influence on extremely severe damage and collapse of rock tunnels due to earthquakes. Various such cases are elaborated on in detail and some mitigation measures are proposed for reducing or preventing the seismic damage of rock tunnels. This study will contribute to understanding the significance of rock mass for rock tunnels residing in a seismic zone.

Cheves Hydropower Project is in the Central Peruvian Andes, N of Lima that generates 825 GWh/year since 2015. The project includes approximately 20 km of tunnels and two caverns. The construction was done mainly in intrusive and the metamorphic rocks; generalized rock burst conditions took place, recording more than 850 stress-events. These events boost themselves in the presence of stiff rocks and geological structures, happening either at the face excavation or behind the face in the reinforced sections. The paper analyses all the factors related to the occurrence of stress-events: overburden, horizontal in situ stress, lithology and stiffness, joint sets and related structures and induced stresses; providing useful criteria, enabling designers to collect data and make some correlations that may be useful for other projects.

An inappropriate design of hard rock pillars can jeopardize the safety and profitability of mining operations in which pillars are used. This paper proposes probabilistic charts for pillar design in hard rock. These charts were established using a two-layer artificial neural network classifier trained with historical data of pillar performances compiled from mine operations worldwide. The pillar data included the pillar height, width, uniaxial compressive strength, average stress and the pillar conditions. The network outputs were used to determine the associated probability of the pillars’ performances and to plot design charts. The overall results showed high classification accuracy (94%), which agreed well with field data and existing studies. It is concluded that the results of this study could improve the empirical design of pillars in hard rock mines as the probability of having a pillar intact or failed can be determined straightforwardly using the proposed design charts.

The Terradets Gorge is essential in the Catalan linear land infrastructure transport network. It serves as a natural boundary between Noguera and Pallars Jussà, facilitating a vital north-south connection for trade and tourism. In this area roads and railways traverse the gorge, despite facing elevations of rock slopes up to 500 meters. Recent incidents have highlighted their traffic vulnerability to rock falls and debris flows. Both administrations, Roads and Railways of the Catalan Government, have concurred addressing these chal-lenges between 2022 and 2023, enabling the comparison between infrastructure mainte-nance policies and revealing similar solutions for protection and mitigation. The experi-ence underscores the effectiveness of collaborative management in the face of geological risk in priority infrastructure corridors, where both authorities coincide. Sharing resources and strategies not only reinforces efficiency but also promotes cooperation among entities, enhancing resilience against future challenges

This paper presents a procedure of ill-posed problem back analysis of multiple landslides to de-termine the reliable shear strength parameters of rock mass. This procedure includes field in-vestigations, determination of instability mechanism, definition of collapse surface on the rep-resentative section, limit equilibrium stability analysis for variable shear strength properties, and limiting the range of possible answers. This procedure was applied for two individual complex translational-rotational landslides in Jajram Golbini No.07 mine. The investigations indicate the similarity and spatial correlation between the mechanical (shear strength) attributes of sliding surface of both landslides. This provide an opportunity to establish two equations for determination of shear strength parameters. Then, the cohesion and friction angle of rock mass were determined by solving these system of equations. The results of back analysis provide very useful information about shear strength parameters of rock mass and fault that can be ap-plied for reliable redesign of mine slope.

During the 19th century, coal mining in the underground of the Belmez urban area has caused subsidence with small cracks that are balanced by jumps of 1cm/year. Recently, a NW–SE direction cracking with distension of the mining roof terrain has been actived by the drainage of a mining operation and the emptying of two water deposits. A Namurian reverse fault that crosses Belmez on the surface has been reactivated as a dextral shear in the Kimmeric phase. By City Council request, this problem has been studied by comparing the natural tensions in the environment. Using a innovative Seismic Geotechnics, 30 m long NE-SW multi-channel reflection profiles are created for the seismic inversion of guided waves that allow to know the inelastic deformation of the terrain. Beneath this Namurian fault, there are the work-ings of coal layers from 40 m depth. The natural stresses, elastic moduli and friction angle have been obtained with the P and Svertical waves, which have been plotted, together with the inelastic Sradial geostatistics, up to 40 m depth.

In high-resolution research with Seismic Geotechnics, compression waves and three orthogo-nal shears are generated to obtain velocities based on the times of the reflected bands. Using an inverse process, the time domain is transformed into depth, up to 100 m, and distortion models are provided with underground images of natural stresses, friction angle, permeabilities, and elastic and inelastic modules using vertical and radial shear waves. By partitioning the energy of seismic waves at a discontinuity or interface, the initiation of rupture is proposed. Through the impact of energy on the heterogeneous ground surface, constructive waves in phase are reflected at the interface when impedance increases with depth and frequency remains constant. If imped-ance decreases with depth, the partition of the reflected wave presents a longer wavelength and is not constructive; it is out of phase, leading to tension and shear that generate pre-ruptures as deformation increases with the absorption of wave amplitude, resulting in the loss of contact be-tween particles. Results from the sliding model and classical mechanics can be compared; they are also applied in rock compression tests.

The Poggio Baldi Natural Laboratory, jointly managed by Sapienza University of Rome's Department of Earth Sciences and NHAZCA SRL, utilizes cutting-edge instruments like LiDAR, drones, radar, and more to monitor a critically stable rock scarp. It aims to understand connections between rockfalls and factors like geo-structural arrangements, thermal effects, seismic activity, and weather, with the goal of creating an early warning system. Research at the lab focuses on geo-structural characterization, analyzing block failure potential, and assessing rockfall hazards. High-res point cloud data and orthoimages help determine discontinuity orientation and rock block volumes. An innovative algorithm enables pixel-based stability analysis. The study compares data from different sources for analysis suitability and identifies active rockfall zones through 3D change detection. Simulations in these zones evaluate potential hazards. Overall, the lab's multidisciplinary approach using advanced tech enhances our grasp of rock slope dynamics in susceptible hilly regions.

The Scaled Span method is an empirical approach for calculating the stability of mine crown pillars: To determine the stability of the rock bridge between the void and the ground surface. It is a methodology that was born in Canada (Carter, 1988) at the end of the 1980s due to a series of problems and subsidence produced by sinkholes and collapses of shallow abandoned mines. The methodology has been refined over the years and has been applied in numerous countries, such as Canada itself, Austria, Spain, Peru, etc. The database has been increasing and the graph of this method makes it possible to establish both the degree of stability and the possible interventions to be carried out in the upper part of the mine or tunnel (since it has also been applied to shallow tunnels). The methodology uses the rock quality index Q and the dimensions of the void. Scaled Span means that the actual width of the cavity is “scaled” or weighted by other parameters such as rock thickness, length, etc. Volcanic caves or lava tubes are often shallow cavities on which buildings and infrastructures are sometimes built, and many of them are also visited by tourists. It is important for this to carry out an analysis of its stability. The most widely used approximation for the analysis of cave stability is the Q index (Jorda, 2016) but it has many limitations since it only considers geometrically the width of the cavity and not the cover thickness (with the exception of the SRF parameter). cave length, among others. For this reason, the scaled width is a good analysis methodology. In the present investigation, the use by its authors is compiled and extended to various volcanic caves in the Galapagos and Canary Islands, and it is concluded that it is a more realistic methodology than that of only Q-span and that it also provides reasonable protocols to follow for access or impediment to the cave.

In 2021, the Tajogaite volcano on La Palma (Canary Islands, Spain) emitted over 200 million cubic meters of volcanic materials, in the form of lava flows, lapilli and ash. Rebuilding damaged infrastructure, estimated in 1,676 buildings and 73.8 km of roads is a crucial priority. Additionally, it is important to explore potential uses for the products emitted by the volcano. Due to their basaltic nature, volcanic slag, lapilli and ash are suitable for manufacturing building materials such as cement, concrete, blocks or bituminous mixtures. This study focuses on the preparation of concrete tiles using products from the Tajogaite volcano. For this purpose, a laboratory-scale manufacturing procedure for concrete tiles was developed, with the premise of being as sustainable as possible, requiring low energy consumption and minimizing the emissions and waste generation. Various dosages of volcanic material were tested in order to check how it affects the samples performance, as well as to optimize the manufacturing process. The obtained materials were characterized using standard testing methods. Standard UNE-EN 1339 was used as a reference, which specifies the materials, properties, requirements and test methods for cement bound unreinforced concrete paving flagsr. The results of flexural strength tests indicate promising prospects for using the volcanic ash in the production of concrete tiles. However, further research is required to enhance products performance.

The Canary Islands is an archipelago of volcanic origin located in the northern Atlantic Ocean about 100 km from the coast of Africa. Numerous eruptive processes took place during its formation, emitting a large volume of volcanic material. The inhabitants of these islands have known how to take advantage of this resource, and historically, lithologies such as trachytes, basalts, trachybasalts, tuffs, ignimbrites or phonolites have been widely used as building stone. At present, the number of active dimension stone quarries is very small and most of them are concentrated in the islands of Tenerife and Gran Canaria. In the southern part of Tenerife, a pumice tuff known locally as "Canto Blanco" and a group of ignimbrites, with different tonalities, belonging to the lithological unit "Ignimbritas de Arico" are exploited. The extraction of these ignimbrites is carried out by the "Guama" quarry and are marketed under the name "Piedra Chasnera". Fracturing is one of the most important factors for assessing the suitability of a rock mass to provide commercially sized blocks for further processing. The main parameters to consider in a study of this nature are the direction of the joints and their distribution in sets, which define the fracturing pattern, and the spacing which controls the dimensions of the blocks in the rock mass. The main objective of this study is to evaluate the quality of the rock mass of the ignimbrite deposit of the "Guama" quarry. Firstly, given the importance of knowing the joint system to ensure profitable production, the main joint sets in the side wall of the quarry were identified. This evaluation is critical because the quarry owner plans expend the extraction as soon as the upper levels (paleosoil and topsoil) are removed. Secondly, the current exploitation front was analysed by characterising the discontinuities. By measuring the direction and length of the joints and using 3D Block Expert software, the spatial distribution of the fractures was assessed, which allowed to establish the size and volume of the effective blocks, i.e., defined by the natural fracturing.