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On the surface of complex landslide areas, other types of slope processes often occur in addition to the landslide movements themselves. However, in order to define the interrelationships or analyse their triggers, it is necessary to have chronological information on their past occurrence. In this study, a spectrum of tree-ring-based (dendrogeomorphic) approaches for spatio-temporal analysis of these processes is presented. The different approaches are applied to a selected complex landslide area with the presence of both creep and rockfall movements. Tree-ring-based data were obtained from standard increment cores as well as from tree roots exposed in tension cracks and from the modified surface of stumps. The presented approaches allowed not only chronological reconstruction of past activity processes but also reconstruction of their spatial activity and even estimation of the rate of displacements of selected landslide blocks. For each methodological approach, their advantages and limitations were evaluated. In addition, the obtained chronological data were used to evaluate potential triggers. The uniqueness of the tree-ring-based data was evident in detecting a wide variability in both the preparatory (up to 2-year periods with above-average rainfall in the case of landslides) and triggering factors themselves (3–5-day rainfall totals for landslides, extreme river discharges for activity tension cracks, or the influence of low temperatures during the winter season). Thus, this study provides a comprehensive overview of dendrogeomorphic approaches that can be used to obtain unique data on the spatio-temporal activity of processes in landslide areas in the past, estimating their rates and preparatory and triggering factors. [ABSTRACT FROM AUTHOR]

Landslide research has benefited greatly from advances in remote sensing techniques. However, the recent increase in available data on land surface movement provided by InSAR techniques can lead to identifying only those areas that were active during data acquisition as hazardous, overlooking other potentially unsafe areas or neglecting landslide-specific geological settings in hazard assessments. Here, we present a case study that serves as a reminder for landslide researchers to carefully consider the geology and geomorphology of study areas where complex active movements are detected using InSAR technology. In an area extensively studied using InSAR and UAV-related techniques, we provide new insights by applying classical approaches. The area is the coastal stretch of La Herradura, and its importance lies in the fact that it has served as an illustrative example in the Product User Manual of the European Ground Motion Service, a platform that provides ground motion data on a European scale. Our approach is to revisit the area and carry out qualitative geological and geomorphological assessments supported by UAV surveys and GIS spatial analysis on a broader scale than previously published investigations. Our classical approach has yielded the following new observations, crucial for risk assessment and land management: active landslides identified by InSAR techniques since 2015 are bodies nested within large mass movements that affect entire slopes. A variety of processes contribute to slope dynamics, such as large slumps, marble rock spreading and block sliding, and surface rock falls and topples. The revised delineation of the landslide bodies reveals an area almost five times larger than previously mapped. These new findings in a well-known area highlight (1) the importance of updating and downscaling previous maps and (2) the ongoing importance of classical fieldwork and desk studies as basic complements to modern InSAR analyses. [ABSTRACT FROM AUTHOR]

Protecting pipelines from impact load due to rockfall in mountainous regions is a challenging problem. Many researchers have studied rockfall characteristics and impact loading, however, there is still a lack of large-scale studies about the impact of rockfall on steel buried pipes. In this study, three large-scale tests were carried out to investigate the response of steel buried pipe, including rock penetration, impact force during penetration, circumferential strain, and vertical deformation of the pipe under different falling heights of a large spherical mass. In order to establish a well-based connection between prototype and large-scale models, a comprehensive scaling rule was applied in a way that the response of the prototype and large-scale models approached the same values. The results showed that increasing drop height causes an incremental rate of peak deceleration of the falling mass, and therefore larger impact forces were measured on the trench surface. The equivalent stiffness of the soil-buried pipe system during the impact load proved that the response of the system was mostly governed by the soil rather than the pipe. For this study, the through-wall bending stress of the pipe at drop heights of 3.5 and 4.5 m exceeded the recommended permissible range, and so failing to satisfy this design criterion. [ABSTRACT FROM AUTHOR]

Rockfall frequently occurs in the mountainous areas and threatens structures such as settlement areas, transportation lines, and agricultural field. The empirical approaches for rockfall mapping have been an attractive research topic in rock mechanics in the recent years, because producing rockfall maps of large areas by using the deterministic and the probabilistic analysis seems difficult due to the necessity of numerous inputs. The cone propagation approach is preferred as a practical tool particularly in the regional scale. The digital elevation model (DEM) of a region prone to rockfall is used for determination of possible propagation zones based on a simple geometric rule known as the energy line angle (reach angle). As a new term, ELAmax_stop was defined to represent the energy line angle that extends to the border of the propagation zone as the maximum run-out distance that is obtained from application of the cone approach to all points (pixels) in source area. The angle denoted as α refers to the threshold slope angle of the steep areas utilized to identify potential source areas by using DEM. Conceptually, the fallen rock blocks within a rockfall-prone region stop within the cone propagation zone, which is bounded by the energy line angles α and ELAmax_stop. While the value of α is susceptible to the resolution of DEM, ELAmax_stop, which exhibits a wide angle range as documented in the literature, is controlled by rock block features together with slope surface properties of the propagation zone. Due to the variability of ELAmax_stop and α depending on the studied region and the resolution of the DEM, the boundary value of the energy line angles between different susceptibility classes need to be adjusted by considering α and ELAmax_stop. By adopting the cone propagation approach to enable adjustable use of energy line angles for rockfall susceptibility mapping, a series of graphical presentations was prepared. These graphical presentations allowed for the prediction of energy line angles corresponding to various rockfall susceptibility classes including very low, low, medium, high, and very high. In addition to the graphical presentations, a series of practical equations were derived for the same purpose. In the final part of the study, a new rating system, namely the run-out distance rating (RDR), was introduced for the preliminary determination of ELAmax_stop. Due to the empirical structure of the methodology, the suggested supportive approach to the practitioners for determining ELAmax_stop should be considered as an initial step that opens to improvement. The proposed methodology in this study was implemented in the regions of Kargabedir Hill and Sivrihisar residential areas in Turkey to prepare rockfall susceptibility maps. [ABSTRACT FROM AUTHOR]

A common practice in mountainous areas for rockfall protection is to cover the top slab of a rockfall shed with a thick granular layer to buffer the impact. However, the weight of the sand is significant, with limited buffering capacity. This paper proposes a novel composite cushion consisting of a flexible buffer and a sand layer. Full-scale rockfall impact tests of 500 kJ were conducted to evaluate the performance of the cushion. Based on the sand layer impact test, DEM parameters for simulating sand were calibrated, and a numerical model of the composite cushion with rockfall impact using FEM-DEM coupling method was constructed. The buffering performance of the composite cushion was compared with the EPS-sand cushion. The study further investigates the effect of buffer height, sand layer thickness, and rockfall mass on impact force and energy distribution using numerical simulations. The results show that (1) the impact force on the composite cushion decreases by 73.2% compared to the sand layer. (2) The buffering performance of the composite cushion is equivalent to that of the 1 m EPS + 0.4 m sand cushion in terms of inhibiting the stress development on the shed slab. (3) The superior buffering performance of the cushion is attributed to the high flexibility of the net and the force-controlling characteristics of the energy dissipaters. Meanwhile, the sand layer plays more of a secondary defense role to prevent direct collision between the rockfall and the shed slab. These findings provide theoretical bases for the engineering design of such composite cushions. [ABSTRACT FROM AUTHOR]

The study of rock slope stability and evolution suffers from many uncertainty factors related to block size and shape, and slope morphology. While nothing can be done to remove the aleatory component of these uncertainties, efforts in reducing the epistemic ones are desirable. This research aims to propose a new analytical solution for calculating rock block volume in the case of three discontinuity sets whose orientation and true spacing are known. Researchers and practitioners can take advantage of such a correct analytical formula thanks to its easiness of use: guidelines based on stereogram are provided in order to explain how to obtain the required input data. The correctness of the equation is demonstrated by comparing the results of the new solution applied to 12 theoretical blocks with those obtained with 3DEC (Itasca Consulting Group). Also, the differences with respect to results obtained with the well-known Palmstrøm's formula are reported. The new methodology is applied to the case study of Elva valley road (Northern Italy), which is overhung by steep rocky cliffs and is subject to the consequences of frequent rockfall phenomena. The results are used to discuss the proposed method's applicability: while it is evident that such a formula is not able to compete with the great potentiality of DFNs, this user-friendly tool can quickly and at no cost assess rock block volume in rockfall or rock slope stability studies. Highlights: The correct analytical solution for calculating rock block volume is demonstrated. The formula is valid in the case of three discontinuity sets. Orientation and true spacing of the three sets are the input of the formula. Validation is performed through a Discrete Fracture Network generator. [ABSTRACT FROM AUTHOR]

Aiming at the problem that the impact force calculation model cannot accurately link the contact force with local deformation, theoretical calculation and experimental research were conducted on block impact to improve the calculation accuracy of the rockfall impact force and impact energy, and then optimize the design of the protective net. Firstly, the elastic net was considered as an elastic film, and the Dirac function was introduced to divide the “unidirectional uniform tensile zone” and the “bidirectional uniform tensile zone”. Secondly, the calculation formulas for the impact force and energy of falling rocks were derived through the Galerkin method, and impact tests were conducted on the elastic nets with different pretension force. Finally, the deformation of the elastic mesh was substituted into the above formula to calculate the impact force and impact energy, and the reasons for the errors were analyzed. Correction coefficient was proposed to correct the results. The maximum errors of the corrected impact force and energy are 2. 8% and 3. 9%. Compared with the existing methods for calculating the impact force and impact energy of rockfall, the proposed calculation method is more simplified. It can be used to calculate the impact force and energy of falling rocks in model experiments, providing a basic basis for optimizing the design of falling rock protection. [ABSTRACT FROM AUTHOR]

The occurrence of rockfalls is a prevalent geological hazard, especially in the Three Gorges Reservoir area of the Yangtze River. Analyzing the pre-rockfall evolution process of hazardous rock mass is crucial for stability assessment, risk monitoring, and evaluation. Generally, numerical analysis is conducted to study the rock stability and failure; however, it is primarily based on the two-dimensional calculation of typical cross-sections without considering the shape of the three-dimensional space of the hazardous rock mass, thus leading to distorted results. To address this issue, this paper proposes a methodological approach for the analysis of the stability conditions of a hazardous rock mass. The approach starts with field investigations and an Unmanned aerial vehicle (UAV) photogrammetric survey to gather data. These data are then used to construct a three-dimensional (3D) geological model of rock mass. Finally, a 3D numerical simulation is performed to analyse the potential failure processes of hazardous rock mass. In this study, we focused on the hazardous Diaozui rock mass of the Qutang Gorge in the Three Gorges Reservoir area (China). We constructed a 3D geological model of the rock mass based on the data from the field survey and UAV photogrammetric survey. Using this 3D geological model, we established a 3D numerical analysis model to assess the rockfall hazard. By utilizing the Strength reduction method (SRM) and simulating the collapse process of the hazardous rock mass, we analyzed the instability mechanism and failure evolution process of the Hazardous Diaozui rock mass. The results illustrated the potential failure mode, the key-oriented wedges of the rock mass, and the potential critical failure point for the hazardous rock mass. These findings provide valuable insights for stability assessment, risk monitoring, and evaluation of the hazardous rock mass in the Three Gorges Reservoir area. [ABSTRACT FROM AUTHOR]

Fragile geological features must undergo frequent structural health assessments to prevent catastrophic failure events. The mechanical behavior of natural sites is largely guided by vibrations of the earth and environmental exposure, but damage is rarely assessed, except empirically. The Chauvet‐Pont d'Arc cave, a UNESCO World Heritage Site, represents a shining example of fragility that would benefit from monitoring. It is overhung by a rock column known as Abraham's pillar that extends out from the cliff like a natural tuning fork. For this study, we monitored dancing movements of this pillar for over 2 years to analyze its elastic response to weather conditions. Using ambient‐seismic‐noise‐based methods, we identified the pillar's first two natural resonance modes. Through extensive monitoring of the site, we observed the striking temporal evolution of these two resonance frequencies on hourly, daily, seasonal, and pluriannual scales in response to changes in air temperature and insolation. Based on thermo‐acousto‐elastic modeling with a simplified 3D geometric structure, we determined how thermally‐induced stress stiffening affects the rock material, by applying convective and radiative heat fluxes to the model. From the results obtained, we suggest a novel quantitative method based on daily observations that can estimate the level of damage within the rock material. Our work provides a foundation for distinguishing between reversible processes and damage for hazard studies in the frame of climate change. Such knowledge is crucial not only for the preservation of heritage sites but also for enhancing risk assessment protocols and informing conservation efforts worldwide. Plain Language Summary: Rock columns are prominent geological features detaching from rock cliffs. The Chauvet‐Pont d'Arc cave, a UNESCO World Heritage Site, is overhung by such a rock column called Abraham's pillar. By seismic sensors, we monitored vibrations of this pillar that continuously oscillates like a natural tuning fork. These vibrations are particularly amplified at two certain frequencies, called natural resonance frequencies, that are related to fixation conditions and health state of the pillar. Their values fluctuate along days and years, and this wandering is strongly linked with air temperature and solar heating over time. We modeled how temperature affects the mechanical properties of the rock material. Based on these results, we suggest a novel method that can estimate the daily level of damage within the rock material, paving the way to enhance rockfall hazard assessment and prevent catastrophic failures. Key Points: The Chauvet‐Pont d'Arc UNESCO site is overhung by a rocky pillar that has been monitored during more than 2 yearsResonance frequencies of pillar's bending modes evolve with thermal forcings at daily and seasonal time scalesThermo‐acoustoelasticity is used to model thermally‐induced stresses and acoustoelastic parameters are proposed as a proxy of rock damage [ABSTRACT FROM AUTHOR]

Rockfalls can often pose a significant risk to the public if protective designs do not properly account for block movement downslope and onto infrastructure facilities. Assessing these hazards is challenging, especially as current empirical and computational methods for predicting trajectories of falling blocks generally do not include the contribution associated with rotational behavior. Research undertaken at the University of New Hampshire, USA, over the last decade has led to the development of Smart Rock (SR) sensors inserted in natural rocks to evaluate these events from the perspective of the falling rock. The latest SRs consist of 3 D printed capsules 58.0 mm in length and 25.4 mm in diameter, equipped with a ±400 g and a ±16 g 3-axis accelerometer, a ± 4000 dps high-rate gyroscope, and an altimeter. Approximately 80 field experiments conducted in New Hampshire and Vermont provided SR data on rockfall at ten different sites. The Smart Rock data allowed more in-depth evaluations of accelerations, rotation rates, and modes of motion with precise time intervals, which cannot be easily captured in video recording systems or other instrumentation techniques. Such measurements are essential to improve our understanding and modeling of rockfall events for more economical and safer design of protective systems. [ABSTRACT FROM AUTHOR]

This study investigates the behavior of rockfall protection on a reinforced concrete semicircular shed against impulse excitation forces by using finite element software ABAQUS and experimental analysis on a free-fall impact test machine. There is limited field knowledge about the response of rockfall protection reinforced concrete semicircular sheds under free-fall impact. The experiments are carried out through the 0.5-m center-to-center diameter of a semicircular reinforced concrete (RC) shed which has a 1.2-m length. The shape of the impactor is cylindrical with a free-fall height of 2.4 m on a semicircular reinforced concrete shed from a free-fall impact test machine. Conventional explicit analysis in finite element software ABAQUS was employed. The concrete damaged plasticity, Johnson–Cook plasticity, and Drucker–Prager models were used to mimic the reaction behavior of concrete, reinforcement, and soil, respectively. The findings from the finite element program ABAQUS were compared to the experimental data, which were found to be in close agreement. Furthermore, the simulation was carried out on the effect of important parameters such as variation in the velocity of the impactor, lining thickness, and length of the RC shed to predict the behavior of reinforced concrete shed. [ABSTRACT FROM AUTHOR]

This study focuses on the characterization of low-velocity (lower than 100 km/h) rockfall impact loads transferring to a thick steel-reinforced concrete (SRC) slab through a protective sand layer. A full-scale experimental test campaign was performed, where each test consisted of releasing a concrete block which, after a vertical free fall, impacts a sand protective layer placed over a SRC slab, in order to represent an isolated rockfall impact to which an actual SRC structure could be exposed. During the impact, the vertical pressure distribution was observed using several pressure cells installed at the sand–slab interface. A total of 35 tests were carried out, systematically combining sand layer thickness (D), block's equivalent diameter (B), and free-fall drop height (H), related to impact velocity. The masses of the released blocks were in the range of 117 to 7,399 kg, corresponding to diameters in the range of 0.42 to 1.79 m. Five free-fall drop heights up to 33 m were considered to reach impact velocities up to 90 km/h , covering the range of most velocities observed in actual rockfall studies. Three thicknesses of the sand layer protecting the thick SRC slab were considered: 1, 1.5, or 2 m. Data reduction from this full-scale impact tests program makes it possible to characterize, for a given thickness of protective sand layer, the time-space pressure pulse distribution applied to the protected structure during the impact for a large range of rock boulder masses and speeds actually observed in the field. [ABSTRACT FROM AUTHOR]

Rockfalls can pose a significant threat to traffic safety in mountainous areas. Galleries covered by a granular layer have proven effective in protecting both the people and the infrastructure from falling rock blocks. However, quantifying the impact for structural design purposes remains challenging as this force is strongly influenced by the shape of the blocks, among other factors. Here, we propose a semi-empirical model to evaluate the maximum value of the impact force exerted by an irregularly-shaped rock block on a granular layer. The model introduces a work-energy ratio (α), which is a dimensionless parameter that depends on properties of both the block and the granular layer. We evaluate a significant dependence of α on the block shape (N*) as well as on the thickness (Ts) and strength-like indentation resistance (f*) of the granular layer. We show that α is lower for blocks with sharp noses (low N*) and for layers with low f*. Furthermore, we identify a threshold value of Ts, above which α becomes independent of Ts. We validate our model on large-scale experiments as well as on a variety of published data and compare the model's performance with that of existing models. The model exhibits superior performance in realistic rockfall scenarios, suggesting a good potential for implementation in gallery design. [ABSTRACT FROM AUTHOR]

Steep slopes in soft rock are characterized by their susceptibility to instability (rockfall, rockslide) due to weathering and erosion of the slope surface. This article deals with the problem of adapting to the increasing height of the scree slope. The construction of a retaining wall in a scree slope in front of a slope of soft rock with a steep face, where a very rapid weathering and erosion process of weathered material takes place, and the simultaneous deposition of material in front of the steep slope is a common solution. Changes in the geometry of the slope and the front scree are taken into account, and at the same time, sufficient safety against rockfall must be ensured. The analysis is shown on a specific example of a steep flysch slope near Split, Dalmatia. The retaining wall solutions are compared in terms of function, cost and sustainability. The construction of a single colossal, reinforced concrete retaining wall shows that this solution is not feasible due to the high construction costs and CO2 emissions of the retaining wall. A model was therefore developed to determine the height of the retaining walls for different construction time intervals and distances from the original rock face. The critical failure modes were investigated for various retaining wall solutions with regard to the highest degree of utilization of the resistance, which also allows the cost-optimized solutions to be determined. By building two or more successive retaining walls at suitable intervals and at an appropriate distance from the original rock face, construction costs and CO2 emissions can be significantly reduced. [ABSTRACT FROM AUTHOR]

On March 18, 2021, at 00:04 UTC, a strong earthquake (Mw 6.0) hit Bejaia city, 200 km east of Algiers. Its epicenter was 15 km northeast of Cap Carbon in Bejaia Bay, making it the largest earthquake recorded offshore since the devastating earthquake (Mw 6.8) in Boumerdes on May 21, 2003. The earthquake had a maximum intensity of VII (EMS 98), triggering hundreds of aftershocks and damaging 2000 houses and social infrastructures, as well as causing several rock falls along the rocky coastline, but no human casualties were reported. The waveform inversion and spectral analysis of the mainshock and its largest aftershocks indicate an alignment along an E-W thrust fault plane offshore, dipping southward, the mainshock seismic moment of M0 = 9.7e + 17 N.m. corresponding to a magnitude Mw = 6.0. The aftershocks illuminated a surface 22 km long (N–S) and 12 km wide; their statistical parameters were assessed by Guttenberg–Richter relationship, Omori decay, and temporal clustering. The b-value is estimated at 0.83, the p value at 0.95, and the n-value at 0.75 (i.e., 75% triggered events), which follows classical patterns of aftershock sequences and suggests the sequence tectonic genesis. Furthermore, previous studies showed that the epicentral area was positively charged by coseismic static stresses transferred from recent events in the Bejaia–Jijel margin. Exactly one year later, on March 19, 2022, a moderate earthquake struck the same epicentral zone, 3 km NW of the first shock, generating a moment M0 = 8.5e + 16 N.m. corresponding to a magnitude Mw = 5.3; its focal mechanism also revealed an E–W striking reverse fault with a small strike-slip component. The present-day local stress field is characterized by a contractional tectonic regime (R′ = 2.99 ± 0.24) and σ1 orientation (N345°E) consistent with the maximum regional compressive stress direction (NNW–SSE). The 2021–2022 Bejaia Bay seismic sequence underlined the active tectonics linking the major E–W offshore thrust fault system and the NW–SE strike-slip Babors Transverse Fault system. This sequence, along with a number of other earthquakes that occurred around the Lesser Kabylia Block (LKB) over the last decade, likely highlights the ongoing incipient subduction process between Africa and Eurasia along the northern Algerian margin. [ABSTRACT FROM AUTHOR]

Ischia (Southern Italy) is a volcanic island of the Phlegrean Volcanic District that was historically affected by multiple geological hazards, including floodings, landslides, rockfalls, and earthquakes. In this study, rockfall stability is analysed with an integrated approach aimed at investigating the rockfall source, the propagation, and the deposition areas. The case study is represented by two outcrops over a 400-m-wide cliff made of Green Tuff and located on the western area of Mt. Epomeo. They are respectively located at 280 and 420 m a.s.l., just uphill the village of Frassitelli, Forio d’Ischia, which is an area of high residential, tourist, and agricultural importance. We analysed the fracture systems of the tuff cliff to compute the kinematic analysis of the potential failure mechanisms and to perform numerical simulations of rockfall scenarios. Successively, numerical simulations of rockfall scenarios were computed based on the acquired structural information. This allowed us to identify the most hazardous scenarios based on the rock trajectories and the percentage of rock blocks affecting the urban area. The influence of the rock shape and volume on the rockfall trajectories was analysed. In the most likely scenarios, we observed that 15–25% of the rock blocks bypass the geomorphological barriers and reach the urban area, with kinetic energy values spanning between 102 and 104 kJ. Such detailed rockfall hazard analysis allowed the definition of the mitigation interventions necessary for the protection of the nearby residential area. [ABSTRACT FROM AUTHOR]

Steep alpine rock slopes undergoing deformation may give rise to concurrent landslide hazards of different type and magnitude. The underlying mechanisms of instability are often challenging to investigate due to their inherent complexity; furthermore, they can occur on poorly accessible terrain, preventing the collection of data by means of traditional field techniques or even inhibiting awareness of hazards. This paper focuses upon one such case, in which a major transportation corridor running along the floor of the Aosta Valley (Western Italian Alps) is affected by significant—and until recently unknown—rockfall hazards promoted by a previously collapsed rockslide still deforming slowly at elevations almost 600 m above the road. In particular, two large discrete blocks (volume > 103 m3) lie precariously at the toe of the slide and could fall downslope at extremely rapid velocity. The design of countermeasures for the stabilization or removal of these blocks would require the assessment of their mechanical interaction with the bedrock and degree of internal fracturing (i.e., possible pervasive damage within the blocks). We perform this task by first exploring potential kinematic styles and damage patterns at failure according to a series of preliminary finite-element models. We then use detailed displacement measurements from remote sensing and in situ monitoring, in conjunction with repeat topographic surveying from a terrestrial laser scanner (TLS) and a drone laser scanner (DLS), to reconstruct the actual kinematics of the blocks. The results substantiate the hypothesis that instability is primarily controlled by transient degradation of friction on a through-going basal rupture surface. Development of a large tensile fracture in one of the two blocks is inferred to be conditioned by increased non-planarity of the slipping joint in comparison with the other block. We highlight that optimized integration of cutting-edge rock slope investigation tools can help address otherwise unresolved key aspects of complex instabilities in steep mountainous areas. Highlights: Two large discrete blocks at the toe of a slowly deforming and highly disaggregated rock slope pose significant concerns to a major transportation corridor in the Western Italian Alps. Knowledge of the underlying mechanisms of instability is required to design mitigation measures, but traditional site characterization is impossible due to difficult terrain. Preliminary numerical modelling, slope monitoring, and repeat topographic surveying are integrated into a coordinated analysis framework to explore kinematic styles, damage patterns, and overall modes of failure. It is shown that the blocks are likely affected by transient degradation of friction on a through-going basal rupture surface of varying roughness, and translate towards the steep apex of the adjacent talus cone as mostly individual entities with negligible influence of brittle fracture damage. [ABSTRACT FROM AUTHOR]

Typical rockfall analysis requires detailed discontinuity measurements; however, the use of conventional contact approaches can be challenging on cliffs. In this study, a novel automatic method for rockfall susceptibility is proposed to identify potential rockfall areas by topographic information on steep slopes generated by a terrestrial laser scanner (TLS). The rockfall susceptibility can be determined using the proposed method via the following four steps: first, automatic spatial information of discontinuity extraction based on high-resolution point clouds; second, defining the spatial intersection areas of discontinuities with different statistical properties; third, evaluating the contribution of discontinuity intersections to rockfalls and estimating potential rockfall hazardous blocks based on kinematic analysis; and finally, mapping the rockfall susceptibility through the overall index. Our method can be used to expedite discontinuity measurements from high-resolution point clouds, optimize the processing of discontinuity statistics for the analysis of rockfall source areas, and permit users to visualize and intuitively access potential rockfall areas to facilitate effective measures to control rockfall hazards or implementation. The method was implemented in MATLAB for excavated slopes, and the credibility of our computational results was verified by visual inspection and a comparison to the source locations of rock detachment events. The results showed that the areas in case 1 with a high susceptibility were in line with the geometry of the discontinuities, and the predicted potential failure areas in case 2 were consistent with the rockfall events. This automated process allows rapid acquisition of potential rockfall areas over a broad-scale survey area, which helps to reduce the time of investigation and the uncertainty in further treatment. Highlights: An automatic mapping method based on high-resolution point clouds was utilized for rockfall susceptibility evaluation. An evaluation method was proposed for potential hazardous rockfall blocks based on discontinuity extraction and kinematic analysis. The method was implemented in MATLAB and validated by actual rockfall events on an excavated slope. [ABSTRACT FROM AUTHOR]

Urban floods/inundation disasters are becoming a prominent problem affecting urban public security due to the impact of global climate change and rapid urbanization. Therefore, research on urban flooding via numerical modelling has important practical significance. According to hydrological and hydrodynamic theories and methods, based on the Storm Water Management Model and the self-developed Graphics Processing Unit (GPU) Accelerated Surface Water Flow and Associated Transport (GAST) model, we explore the best coupling mode, and take Xiaozhai block in Xi'an, China, as the research object to study, through the selected mode, the impact of the change of local land use type on surface inundation and pipe network. The results show that the hydrology–hydrodynamic coupling model (G-S) is more realistic, and its simulation results are more in line with the actual urban flood processes. The results are expected to provide help to other experts and scholars in future model coupling research. [ABSTRACT FROM AUTHOR]

The Heshui area within the Ordos Basin holds significant strategic importance for the extraction and development of tight oil resources in the Changqing Oilfield. This study extensively explored the geochemical features and distribution tendencies of source rocks in the Chang 7 member, utilizing core samples and logging data for a comprehensive analysis. A more advanced model was utilized to predict the dispersion of Total Organic Carbon (TOC) in the Chang 7 member source rock. The properties and hydrocarbon generation potential of source rocks were thoroughly assessed through a comprehensive analysis that involved evaluating their total organic carbon content, pyrolysis parameters, and reflectance (Ro) values. The research concluded that the source rocks boast substantial organic matter, predominantly categorized as type II-I organic material. The thermal maturation levels span from low maturity to maturity, signifying significant potential for oil generation. Generally, the source rock quality falls within the range of good to excellent. Sedimentary patterns notably influence the distribution of hydrocarbon-source rocks. The northeastern sector of the study area is situated in an area characterized by deep to semi-deep lake sedimentation, making it the primary location for the presence of Chang 7 member hydrocarbon source rocks. With a thickness ranging from 40 to 70 m, this zone becomes a pivotal focus for the potential exploration of tight oil resources in the future. The results of this study offer crucial insights for understanding the geochemical characteristics of hydrocarbon source rocks, evaluating their potential for hydrocarbon generation, and forecasting favorable zones for oil and gas exploration in similar regions. [ABSTRACT FROM AUTHOR]

Reinforced concrete (RC) structural members could be subjected to impulsive impact loads due to various effects such as the collision of masses driven by rockfall, flood, landslide, avalanche, the crash of vehicles to structural elements in highway and seaway, airplane landing contact, the acting of explosion-induced air shock waves on structural elements as impulsive loads. The conventional design of RC slabs and similar structural members is carried out regarding vertical static and lateral dynamic loads such as earthquake and wind effects. However, the design phase mostly ignores impulsive loads such as impact and blast. Thus, these effects pose risks that the structures experience heavy damage or total collapse. Strengthening RC slabs with textile strips has become a preferred strengthening technique to prevent the collapse of structures and limit damage to structural elements. This study strengthened RC slabs with basalt textile reinforced mortar (TRM) strips in different widths, and layout patterns were tested for low-velocity impact load. In addition, the effects of BFRP fan-type anchors near the impact point on the behavior have also been investigated. The effect of various applied strengthening patterns on impact load transferred to specimens, dynamic responses such as acceleration, displacement, maximum strain, and dynamic failure modes occurred were investigated and interpreted in detail. The experimental results have also been compared with the improved finite element model (FEM) generated. It is demonstrated that the present FEM can be used to evaluate the impact response of the RC slabs with TRM strips. [ABSTRACT FROM AUTHOR]

Rockfalls in mines represent one of the most hazardous events for miners, posing significant risks to safety, equipment, and operations. These incidents occur when rock or debris falls from the walls of a mine, often without warning, and can be triggered by geological factors, blasting practices, ground vibration, water infiltration, stress redistribution and timedependent behaviour of rock. Apart from this, the bench parameters, such as the slope angle of the bench, the friction angle of the material, bench height and width, affect the rockfall. The rockfall incidents history that occurred in the past several years suggest that rockfalls in opencast mines led to the fatal injuries of many individuals. The problems faced due to rockfalls are not repetitive, but they are disastrous in opencast mines once they occur. So, it is necessary to investigate the rockfall in an opencast mining industry. It is also observed from the literature that the kinetic energy of a rockfall helps determine the intensity of rockfall in a mine. Understanding these factors and implementing preventive measures and rapid response strategies is crucial in mitigating rockfall risks. Hence, this study investigates rockfall phenomena in a high wall open cast by determining the kinetic energy of a rockfall. A parametric study has been conducted to determine the effect of various bench parameters on the kinetic energy of rockfall. A predictive model is developed to determine the kinetic energy of rockfall concerning various factors affecting rockfall. The predictive model is also validated using three case studies of high opencast mines. The results from the predictive model and the numerical model for the case study mines match the predictive model that can predict the rock fall intensity for opencast mines. The study also aims to assess the potential risks posed to workers, equipment, and infrastructure in highwall opencast mines. The findings provide valuable insights for implementing appropriate safety measures and developing effective strategies to mitigate rockfall hazards. [ABSTRACT FROM AUTHOR]

The normal restitution coefficient of rockfall is the key parameter to determine the trajectory. The aim of the study is to reveal the influence of collision velocity and material parameters on the normal restitution coefficient of rockfall. The theoretical model of the rock sphere and the plate collision was established based on the elastic-plastic assumption. Furthermore, the collision between the rock sphere and the plate was simulated through the ABAQUS, and the velocity of the rock sphere was monitored in the collision process. The results show that numerical simulation and theoretical calculation are in good agreement, and the maximum difference is within 5% . The confining pressure causes the contact stress in the plastic zone to be greater than the elastic limit of the material. With the increase of collision velocity, the normal restitution coefficient of the rock sphere gradually decreases, and the decline rate gradually decreases. The normal restitution coefficient of the rock sphere decreases with the increase of elastic modulus and increases with the increase of elastic limit, which has a linear relationship. Poisson's ratio has little effect on the normal restitution coefficient of the rock sphere. [ABSTRACT FROM AUTHOR]

Gravitational processes on cut slopes located close to infrastructure are a high concern in mountainous regions. There are many techniques for survey, assessment, and prognosis of hazardous exogenous geological processes. The given research describes using UAV data and GIS morphometric analysis for delineation of hazardous rockfall zones and 3D modelling to obtain an enhanced, detailed evaluation of slope characteristics. Besides the slope geomorphometric data, we integrated discontinuity layers, including rock plains orientation and fracture network density. Cloud Compare software 2.12 was utilised for facet extraction. Fracture discontinuity analysis was performed in QGIS using the Network GT plugin. The presented research uses an Analytical Hierarchy Process (AHP) to determine the weight of each contributing factor. GIS overlay of weighted factors is applied for rockfall susceptibility mapping. This integrated approach allows for a more comprehensive GIS-based rockfall susceptibility mapping by considering both the structural characteristics of the outcrop and the geomorphological features of the slope. By combining UAV data, GIS-based morphometric analysis, and discontinuity analysis, we are able to delineate hazardous rockfall zones effectively. [ABSTRACT FROM AUTHOR]

Research on high-temporal-resolution rock slope monitoring has tended to focus on scenarios where spatial resolution is also high. Accordingly, there is a lack of understanding of the implications for rock slope monitoring results in cases with high temporal resolution but low spatial resolution, which is the focus of this study. This study uses automatically captured photos taken at a daily frequency by five fixed-base cameras in conjunction with multi-epoch Structure-from-Motion (SfM) photogrammetric processing techniques to evaluate changes in a rock slope in Majes, Arequipa, Peru. The results of the monitoring campaign demonstrate that there are potential issues with the common notion that higher frequency change detection is always superior. For lower spatial resolutions or when only large changes are of concern, using a high-frequency monitoring method may cause small volume changes that eventually aggrade into larger areas of change to be missed, whereas most of the total volume change would be captured with lower-frequency monitoring intervals. In this study, daily change detection and volume calculation resulted in a cumulative rockfall volume of 4300 m3 over about 14 months, while change detection and volume calculation between dates at the start and end of the 14-month period resulted in a total rockfall volume of 12,300 m3. High-frequency monitoring is still the most accurate approach for evaluating slope evolution from a rockfall frequency and size distribution perspective, and it allows for the detection of short accelerations and pre-failure deformations, but longer-term comparison intervals may be required in cases where spatial resolution is low relative to temporal resolution to more accurately reflect the total volume change of a given rock slope over a long period of time. [ABSTRACT FROM AUTHOR]

Massive sediment pulses in catchments are a key alpine multi-risk component. Substantial sediment redistribution in alpine catchments frequently causes flooding, river erosion, and landsliding and affects infrastructure such as dam reservoirs as well as aquatic ecosystems and water quality. While systematic rock slope failure inventories have been collected in several countries, the subsequent cascading sediment redistribution is virtually unaccessed. For the first time, this contribution reports the massive sediment redistribution triggered by the multi-stage failure of more than 130 000 m3 from the Hochvogel dolomite peak during the summer of 2016. We applied change detection techniques to seven 3D-coregistered high-resolution true orthophotos and digital surface models (DSMs) obtained through digital aerial photogrammetry later optimized for precise volume calculation in steep terrain. The analysis of seismic information from surrounding stations revealed the temporal evolution of the cliff fall. We identified the proportional contribution of > 600 rockfall events (> 1 m3) from four rock slope catchments with different slope aspects and their volume estimates. In a sediment cascade approach, we evaluated erosion, transport, and deposition from the rock face to the upper channelized erosive debris flow channel, then to the widened dispersive debris flow channel, and finally to the outlet into the braided sediment-supercharged Jochbach river. We observe the decadal flux of more than 400 000 m3 of sediment, characterized by massive sediment waves that (i) exhibit reaction times of 0–4 years in response to a cliff fall sediment input and relaxation times beyond 10 years. The sediment waves (ii) manifest with faster response times of 0–2 years in the upper catchment and over 2 years in the lower catchments. The entire catchment (iii) undergoes a rapid shift from sedimentary (10 2 –10 3 mma-1) to massive erosive regimes (10 2 mma-1) within single years, and the massive sediment redistribution (iv) shows limited dependency on rainfall frequency and intensity. This study provides generic information on spatial and temporal patterns of massive sediment pulses in highly sediment-charged alpine catchments. [ABSTRACT FROM AUTHOR]

On April 18, 2023, a rockslide occurred in Torkham town in Pakistan, near the border with Afghanistan. The rockslide buried trucks and people, resulting in seven deaths and many injuries. The area is prone to natural disasters such as earthquakes, landslides, and floods. The rockslide was triggered by heavy rainfall and may have been exacerbated by slope cutting for road widening. The authors recommend slope stabilization measures, such as drainage systems, vegetation planting, retaining walls, and rockfall barriers, to prevent future disasters. [Extracted from the article]

Rockfalls are ubiquitous products of landscape evolution in steep mountainous terrains. Among other effects, they pose a significant concern to the management of transportation corridors located on valley floors. Here, we describe the field application of a ground-based Doppler radar that performs real-time, long-range, wide-area detection and tracking of rockfalls and related slope hazards. We deployed the instrument at the Ruinon landslide, where accelerated deformation of upper chaotic debris has for several months promoted secondary mass wasting processes of extremely rapid velocity. In particular, large rolling boulders had the potential to propagate beyond the toe of the landslide and impact a road that connects important localities in the Italian Alps interiors. The Doppler radar was programmed to actuate a pair of traffic lights so that a predefined exclusion zone could instantly be enforced for approaching vehicles upon initial movement detection. We discuss the setup of the alarm system, the main observations collected during the monitoring campaign, and how this technique may enhance safety in areas critically exposed to rockfalls as well as our understanding of rockfall dynamics in general. [ABSTRACT FROM AUTHOR]

Different approaches exist to describe the seismic triggering of rockfalls. Statistical approaches rely on the analysis of local terrain properties and their empirical correlation with observed rockfalls. Conversely, deterministic, or physically based approaches, rely on the modeling of individual trajectories of boulders set in motion by seismic shaking. They require different data and allow various interpretations and applications of their results. Here, we present a new method for earthquake-triggered rockfall scenario assessment adopting ground shaking estimates, produced in near real-time by a seismological monitoring network. Its key inputs are the locations of likely initiation points of rockfall trajectories, namely, rockfall sources, obtained by statistical analysis of digital topography. In the model, ground shaking maps corresponding to a specific earthquake suppress the probability of activation of sources at locations with low ground shaking while enhancing that in areas close to the epicenter. Rockfall trajectories are calculated from the probabilistic source map by three-dimensional kinematic modeling using the software STONE. We apply the method to the 1976 MI = 6.5 Friuli earthquake, for which an inventory of seismically-triggered rockfalls exists. We suggest that using peak ground acceleration as a modulating parameter to suppress/enhance rockfall source probability, the model reasonably reproduces observations. Results allow a preliminary impact evaluation before field observations become available. We suggest that the framework may be suitable for rapid rockfall impact assessment as soon as ground-shaking estimates (empirical or numerical models) are available after a seismic event. [ABSTRACT FROM AUTHOR]

According to a recent study, no patches of snow survived on the hills of Scotland from the winter of 2022/2023 to the winter of 2023/2024. The study, which has been conducted annually since 1996, found that the lack of snow was due to above-average temperatures and below-average precipitation levels. The disappearance of the snow patches was observed across various regions of Scotland, including the Southern Uplands, Central and West Highlands, North West Highlands, and North East Highlands. This is the eighth time in recorded history that all snow has vanished in Scotland in two consecutive years. [Extracted from the article]

High mountains are climate change hotspots. Quickly rising temperatures trigger vegetation shifts such as upslope migration, possibly threatening mountain biodiversity. At the same time, mountain slopes are becoming increasingly unstable due to degrading permafrost and changing rain and snowfall regimes, which favour slope movements such as rockfall and debris flows. Slope movements can limit plant colonization, while, at the same time, plant colonization can stabilize moving slopes. Thus, we here propose that response of high mountain environments to climate change depends on a 'biogeomorphic balance' between slope movement intensity and the trait-dependent ability of mountain plants to survive and stabilize slopes. We envision three possible scenarios of biogeomorphic balance: (1) Intensifying slope movements limit vegetation shifts and thus amplify instability. (2) Shifting ecosystem engineer species reduce slope movement and facilitate shifts for less movement-adapted species. (3) Trees and tall shrubs shifting on stable slopes limit slope instability but decrease biodiversity. Previous geomorphic, ecological and palaeoecological studies support all three scenarios. Given differences in ecologic and geomorphic response rates to climate change, as well as high environmental heterogeneity and elevational gradients in mountain environments, we posit that future biogeomorphic balances will be variable and heterogeneous in time and space. To further unravel future biogeomorphic balances, we propose three new research directions for joint research of mountain geomorphologists and ecologists, using advancing field measurement, remote sensing and modelling techniques. Recognizing high mountains as 'biogeomorphic ecosystems' will help to better safeguard mountain infrastructure, lives and livelihoods of millions of people around the world. [ABSTRACT FROM AUTHOR]

Landslides are common across Canada and they pose hazards to human safety, economic activities, and the environment. Robust risk management strategies are necessary for sustainable development. A slope risk management framework has been adopted by the geotechnical community for approximately four decades allowing a systematic, consistent and transparent framework for managing risks. Implementing this framework is associated with uncertainties embedded in our estimates of risk. This paper presents a brief summary of the sources and categories of uncertainty in geotechnical slope engineering and focuses on two topics: (1) estimates of uncertainty in risk calculations and (2) temporal changes in landslide likelihood as a function of weather and steps towards estimating landslide risk changes with climate change. The paper argues that a quantitative risk assessment should not focus on the final risk calculation, but the overall knowledge gained. This allows comprehensive documentation of sources of uncertainty and how they impact geotechnical and risk assessments. Furthermore, the paper outlines approaches to define quantitative correlations between rock fall occurrences and weather, which can be leveraged to estimate changes in rock fall risk with climate change. The paper corresponds to, and expands on, the 2021 Canadian Geotechnical Colloquium. [ABSTRACT FROM AUTHOR]

Objectives: Rockfall occurs frequently in the mountainous areas of southwest China, which is easy to cause huge casualties and property losses. A rapid simulation method of the collapse process is urgently needed. At present, the commonly used collapse simulation software still has obvious shortcomings, such as low terrain accuracy, failure to consider the structural characteristics of rock mass, failure to realize block collision and fragmentation, etc., and the logic operation based on central processing unit (CPU) limits the calculation speed. A new method for rapid simulation of the three-dimensional motion process of collapse is proposed. Methods: The unmanned aerial vehicle (UAV) aerial photography modelling combined with field investigation is used to obtain the slope surface model and determine the characteristic parameters of rockfall. The simulation software of large-scale collapse movement process is developed using Unity3D platform which integrates PhysX physics engine and central processing unit-graphics processing unit (CPU-GPU) parallel computing capability. Results: The software can reproduce the whole process of collapse-impact-fragmentation-accumulation. It can output the three-dimensional trajectory, velocity, energy and jumping height of collapse, which provides reliable basis for the design of collapse prevention and control. Taking Xiejiayan collapse in Nayong, Guizhou Province as a prototype case, three-dimensional simulation and verification of the collapse movement process are carried out. The simulation results of the rockfall accumulation range are in good agreement with the field investigation of the rockfall accumulation range at the bottom of the slope, and the movement characteristics of the simulated single block rock conform to the real physical laws, which indicates the feasibility and practicability of this method. Conclusions: This method can solve the problem of simulation, analysis and visualization of the whole process of three-dimensional movement of rockfall. [ABSTRACT FROM AUTHOR]

The process and dynamics of rock fragmentation during the collapse of rockfalls and rock avalanches is a poorly developed topic. The most severe fragmentation often leads to the formation of a rock dust that rises to form a cloud suspended in the air. The understanding of fragmentation processes is hampered by the environmental disturbances that alter the dust cloud deposit shortly after deposition. Here, we study the fragmentation of the October 2017 Pousset rockfall, detached from a NNE facing steep bedrock wall in the permafrost zone, that involved 8,300m3 of metamorphic rock and fell about 800 m. The collapse generated large boulders which rolled downslope and a thick and large dust cloud. The source and deposit were investigated, and dust cloud material was sampled at different locations to reconstruct an exponential thickness distribution and perform grain size characterization. The fragmentation energy was estimated by integrating the spectrum of the grains assuming that the fragmentation energy is proportional to the generated area. The fragmentation energy was found to be about 0.4% of the initial potential energy. Most probable fragmentation points and block deposition areas were evaluated and positioned by means of the HyStone 3D rockfall simulator. Furthermore, we calculated the flow rate of the suspended powder generated by the fragmentation process and compared the results with observations available for the evolution of the phenomenon and the collected samples. The Pousset event, in its relatively simple dynamics, may be a good testing ground to address the current theories of rockfall and rock avalanche fragmentation and dust cloud behavior. [ABSTRACT FROM AUTHOR]

Rockfall remains a prominent hazard for transportation corridors worldwide. Recent studies have shown promising results in resolving the relationships between rockfall activity and triggers, including in some cases detecting precursor activity prior to failure, which could have implications to improving safety and performance of transportation corridors. The aim of this study is to better understand rockfall failure processes and triggers for cut slopes in interbedded sedimentary rock through a long-term study using photogrammetry data with high spatiotemporal frequency. The combination of daily data, high-precision rockfall volume estimation, and 22-month monitoring duration is unique among studies that evaluate rockfall triggers and allows us to derive insights into differences in rockfall triggering between blocks of different volumes. The data collected allowed the relative frequency of rockfalls of different volumes to be well-constrained for volumes ranging from 0.01 m3 up to 76 m3 (the largest event that occurred during the monitoring period). A quantitative comparison between precipitation and rockfall activity established that precipitation was the primary trigger for rockfall at the site, with only 1.4% of 24-h photo intervals without precipitation having at least one rockfall, as compared to 25.0% of photo intervals with precipitation (and 57.1% of photo intervals with at least 5 mm of precipitation). The marginal impact of additional rainfall above 8 mm per 24-h period on rockfall probability was negligible among all rockfalls observed, whereas the probability of the largest rockfalls at the site (> 1 m3) occurring continued to increase as a function of precipitation up to 20 mm per 24-h period. Detailed analysis of change data leading up to the largest (76 m3) rockfall observed illustrated the progressive failure mechanism of the block, including observations of forward toppling motion and smaller precursor rockfalls around its perimeter. This rockfall was also used for a proof-of-concept demonstration of the potential for a spatiotemporal rockfall density metric to be used to help identify areas of potential hazard. Ultimately, the findings from this study contribute to knowledge on rockfall processes outside alpine regions, which have historically been less well-studied. [ABSTRACT FROM AUTHOR]

In this research article, we propose a practical methodology for evaluating the affecting potential of detachment areas in rockfalls. Our innovative approach combines an assessment of the visibility of rockfall source areas, with reference to specific rockfall scenarios and elements at risk, considering the rockfall Susceptibility Index to Failure (SIF) of these areas. The result is the characterization of source areas through a rockfall Source Affecting Index (SAI), which considers both the morphology of the slope and the geostructural conditions of the rock walls. This information can be very useful since it aids in optimizing more in-depth analyses, as well as the placement of monitoring instruments or stabilization systems. The proposed methodology has been implemented in the open-source software QGIS through the development of an easy-to-use plugin named Ranking of the Affecting Potential of Detachment Areas in Rockfalls, or "RADAR". RADAR is designed to be used in conjunction with QPROTO, a well-known QGIS plugin for preliminary rockfall susceptibility/hazard analyses based on a visibility analysis and a simplified mechanical method. To demonstrate the effectiveness of the proposed approach, an application to a case study located in the Western Alps (Bardonecchia, Italy) is presented and discussed in the paper. [ABSTRACT FROM AUTHOR]

Rockfall events represent a significant hazard in mountainous regions, putting human safety and critical infrastructure at risk. Various mitigation devices are available, among which, Rockfall protection embankments (RPEs) located in natural soil are passive defense work suitable for high-energy and high-frequency events. Currently, limited research has been conducted in this area, with the Austrian standard ONR 24810 providing the sole codified design method. A parametrical analysis involving both the RPE geometry and the impact features was developed by Abaqus/Explicit FEM code, with 2270 cases overall. The research aims to identify conditions under which RPEs effectively stop falling blocks, focusing on two failure mechanisms: the block pass over the RPE after impacting the upstream side bank and the RPE structural collapse. Additionally, the interaction between RPEs and their foundations during the impact is explored. The results provide valuable insights into the dynamic behavior of these structures. In terms of design considerations, this study offers analytical equations to quantify crater depth and foundation stress induced by the impact. Furthermore, design charts are developed to assess the block passing over verification and the structural collapse verification. [ABSTRACT FROM AUTHOR]

The purpose of this work is to analyze the stability of four slopes along the Penipe–Baños road, which is situated in the provinces of Chimborazo and Tungurahua and where there are occasionally rockfalls that hinder passage and endanger road users. The methodology used to conduct the analysis was based on data collection with the help of remote techniques such as structure from motion, which allows us to obtain slope data using photogrammetry. Empirical methods such as slope mass rating, Q-slope, the kinematic method and the Rockfall Hazard Rating System method were used. These methods were evaluated with Rocfall3 software for the analysis of the fall trajectory of rock blocks. The results of this work show that the slopes studied do not represent a greater risk to the road than other slopes close to those studied, but these could not be analyzed due to their lack of accessibility and the danger of obtaining data under those conditions. The study of these different methods demonstrates the reliability of low-cost, remote techniques in the facilitation of analysis in places with similar conditions. [ABSTRACT FROM AUTHOR]

The ultimate objective of modern engineering applications in mining and material science is to develop good quality novel materials with desirable qualities. Machine Learning (ML) is used in the mining industry to provide solutions to complex problems of the mining industry and improve the efficiency of the overall system. ML methods are increasingly being used by materials scientists to uncover hidden trends in data and generate predictions. Furthermore, data centric techniques can provide useful insights into the basic processes that influence material behaviour while simultaneously reducing human labour in large data processing. The ability of persons to find new materials and infer complex relationships is important for the development of new materials. Large amounts of machine-readable data must be available to use statistical methodologies to speed materials research. In mining engineering, ML can be used for analyzing geographical data, assessing the risk of rock fall, predicting equipment failures and impact of mining activities on the environment etc. Material science data may be used in a variety of ways, including property prediction, the search for new materials and discovering synthesis methods. Selecting proper machine learning techniques to provide solutions is very important and that is discussed here. The purposes of this paper are to provide a comprehensive list of different ML techniques which are applied for the mining and material science domain. [ABSTRACT FROM AUTHOR]

Santa Maria dell'Isola is a rocky promontory surrounded by the Tyrrhenian Sea and located in Tropea municipality in Vibo Valentia Province (Calabria, southern Italy) (Fig. The preliminary results discussed herein suggest that the possible causes of the instability phenomena are imputable to the sandstone rocks' weak nature, the rock masses' high fracturing state, and the intense erosive processes by sea wave energy at the cliff foot. They show the topographic changes caused by rocks detached and the material accumulation at the foot of the cliff Conclusion Assessing the cause of the slope instability and focusing on site-specific geological characteristics are crucial steps before projecting suitable consolidation interventions. [Extracted from the article]

Many existing ground reinforced embankments are experiencing deterioration, meanwhile the risk of rockfall is aggravated by the weathering and the infiltration of rainfall. However, research on the assessment of the residual characteristics and efficiency of post-impact embankments is currently insufficient. This article conducts model experiments to observe the deformation behavior and damage evolution of embankments impacted by multiple medium-energy rockfalls, and to investigate the mode of energy dissipation. The experimental results show that the deformation evolution of the embankments undergoes three phases: soil compaction, interfacial slip between geo-inclusions, and backward leaning. The dissipative kinetic energy is dissipated by soil compaction and friction between geo-inclusions, and the proportions of energy dissipated by the two modes in the three phases are ≥9:1, 9:1~7:3, and 7:3~5:5. The dissipation capacity and the distribution of dissipated energy are affected by geometry of cross-section at which the impact occurs. The simplified damage assessment criterion, based on the geometries of the cross-section during the successive impacts, is proposed to assess the current damage degree of post-impact embankments. And the precision and applicability of the criterion can be improved by understanding the structural deformation evolution and deformation mechanism in each phase. The proposed criterion is proven feasible by its agreement with experimental results. These findings should be beneficial to the design of ground reinforced embankments. Highlights: The deformation evolution of GREs is divided into soil compaction, interfacial slip between geo-inclusions and backwards leaning. The impact energy is dissipated by soil compaction and friction between geo-inclusions. The proportions of energy dissipated by the two modes in the three phases are ≥ 9:1, 9:1~7:3, and 7:3~5:5. A simplified damage assessment criterion is proposed to assess the residual efficiency of the post-impact embankments. [ABSTRACT FROM AUTHOR]

In this paper, an advanced rheological model for impacts of ellipsoidal blocks on deformable ground surfaces, introducing the effects of block eccentricity and orientation at impact, is presented. This allows us to assess impact penetration and force, restitution coefficients, and block trajectories. A parametric analysis was carried out by considering different block aspect ratios, impact angles and initial block orientations at impact. The results are presented in terms of restitution coefficients, penetration and force time histories, maximum penetration depth, maximum force and rotational/total kinetic ratios. Impacts along the major block axis, versus those along minor axis, are characterized by larger penetrations (ranging from 3.3 to 50%), shorter impact durations (ca 50%) and very slightly larger vertical forces (ranging from 0.3 to 60%) according to the model parameter used. In contrast, the impact angle is shown to strongly affect maximum penetration and force values, and markedly increase rotation at impact. Analogously, normal restitution coefficient is severely dependent on impact angle, with a variation of more than two orders of magnitude. A mathematical expression for computing the energetic restitution coefficient from the normal and tangential apparent restitution coefficients and the ratio between the rotation and total kinetic energy is proposed. This overcomes the drawback of classical restitution coefficients greater than one when a change in block rotation occurs allowing us to bracket the coefficient of restitutions values to support and improve classical rock fall simulations also highlighting their intrinsic limitations. Finally, the effects of block geometry and initial angular velocity on rockfall simulations were analyzed by implementing the approach in the HyStone simulation code. The simulated frequencies of the maximum height during each ballistic trajectory follow an exponential distribution, whereas those for normal and tangential apparent restitution coefficients follow normal distributions. Highlights: A new rheological model for impacts of ellipsoidal blocks is formulated. The model provides impact variables for different impact angles, initial orientations and block shape. Model results are used to compute restitution coefficients. Rockfall numerical simulations with HyStone implementing the extended impact model are performed. Statistical distributions of the normal and tangential apparent restitution coefficients are examined. [ABSTRACT FROM AUTHOR]

San Nicola Island, pertaining to the Tremiti Archipelago (Southern Adriatic Sea, Italy), is widely affected by cliff retreat and gravitational phenomena which severely threaten its monumental historical and natural value. In this study, geomorphological features of the area were derived following a stepwise approach, combining multitemporal stereoscopic aerial photo interpretations with morphometric analyses and detailed field surveys. A rockfall susceptibility map was created following a heuristic approach based on morphometric and geothematic parameters, accounting for slope, slope aspect, outcropping lithologies, structural discontinuities density, distance from landslide scarps, and presence of anthropic caves. Cliff sectors set on dolomitic limestones feature the highest susceptibility values, especially along the southeastern sector; medium values, instead, are found along the island flanks and along scarps located within the inner sectors; and the lowest values are detected on summit tabular surfaces. The achieved results were compared with historical maps and seismic data derived from local and national archives and catalogues, respectively. These analyses allowed us to define the role played by litho-structural and tectonic features on landslide occurrence and distribution, and their interplay in driving landscape evolution over centuries. Finally, this work represents a valuable scientific tool to support geomorphological studies for landslide hazard assessment and proper territorial planning in any other small insular areas, showing similar geological–geomorphological features and landscape values. [ABSTRACT FROM AUTHOR]

In 1999, Alberta Transportation and Economic Corridors (TEC) implemented the Geohazard Risk Management Program (GRMP) to identify, assess, monitor, and prioritize the mitigation of risk resulting from geohazard events at specific sites along the provincial highway network. The GRMP was developed to address a variety of geohazard types including rockfall hazards that occur at natural and constructed (cut) highway backslopes. An evaluation of various methods for the condition assessment of rockfall geohazards, including TEC's current GRMP risk rating system, has been completed with the intent of better understanding the suitability of each method as TEC transitions to a formalized GAM program. The GRMP risk rating values for selected rockfall geohazard sites along highway corridors in Alberta were compared to values developed from the results of five established rock mass and rock slope rating systems. The results of this study demonstrate that TEC's current GRMP risk rating system is a viable tool for the condition assessment and performance monitoring of rockfall geohazards, which could be utilized within a formalized GAM program, further benefitting from years of recorded application in Alberta. Of the other rating systems tested, the rockfall hazard rating system (RHRS) showed a strong correlation with the GRMP risk rating while Q-Slope, the Geological Strength Index (GSI) and Rock Mass Rating (RMR) correlation were marginal but displayed a potential for use as condition assessment tools. The work presented in this paper provides the first evaluation of rock slope rating systems for rockfall hazards along corridors in Alberta, directly comparing them to the slope performance as observed by TEC in a quantitative manner. [ABSTRACT FROM AUTHOR]

After interviewing surviving soldiers of Hannibal's alpine invasion of Italia and sketching out the Punic Army route, Polybius, a Greek general serving as advisor to Scipio Aemilianus, retraced the Hannibalic invasion of 218 BC, in or about 150 BC. Polybius later recounted Hannibal's route from Cartagena through the Pyrénées and Gaul (France) to the Rhône River, crossing near Arles, north to Orange, Drôme River to the Durance, diversion to the Guil River, and on to the Col de la Traversette. At ~ 3000 m asl, the Traversette provides a vantage point overlooking the Po River and the vaunted, much discussed rockfall, a ~ 250 m wide rubble mass that blocked passage of Hannibal's elephants and horses. Soldiers could pass, but clearing a path for animals took three days to allow the army to recover in the wide valley plain below, prior to exfil onto the lower Po River plains. Polybius probably spent scant time at the rockfall but noted it was a two-stage event, older rock largely eroded, partly superposed by younger rock. This brilliant observation and assessment qualify Polybius as probably the first stratigrapher in history. His separation of rockfall lobes on lichen cover and weathering/tonal contrasts, marked a seminal event in earth science history. [ABSTRACT FROM AUTHOR]

The studied rock collapse structure is located on the Liburnian coast (Rijeka Bay, channel zone of the NE Adriatic). The relief of the southern part of this coast, with a length of 6.5 km, is a large escarpment with very steep to vertical slopes reaching heights of 100 m above sea level, as a result of tectonic movements along the Kvarner fault zone. These events probably led to a sudden relaxation of the highly fractured rock mass. The progressive expansion occurred at locations where previously favourably oriented faults and fissures had formed a polygonal rock collapse resembling a rock-slide which is the focus of this study. Another aim of this study is to reconstruct and explain the complex morphological evolution of the studied landslide, from the pre-failure deformations, through the failure itself, to post-failure displacements, as well as possible future instabilities. Recent techniques to survey the instability, location and to analyse the evolution of the rupture surface and its dimensions were combined (Unmanned Aerial Vehicle, Side Scan Sonar and Remotely Operated Vehicles). The estimated total volume of displaced rock mass is 950,000 mi The lower part of the instability phenomenon was submerged during the Holocene sea level rise. Since then, a large part of the displaced rock mass has been in a stable position, with sporadic rock falls. However, given unfavourable orientation and discontinuity characteristics, as well as unfavourable environmental influences, possible instabilities might also be expected in the future. [ABSTRACT FROM AUTHOR]

Cultural heritage sites can be affected by landslides, often causing damage to their integrity, value, and accessibility. Several studies worldwide were focused on the assessment of the potential threats that landslides can pose to the preservation of cultural heritage sites. This article aims to review landslide studies at cultural heritage sites worldwide, analyzing the publications' temporal distribution, selected methods, geographical and climate contexts, and investigated landslide types. We analyzed a database of 331 publications from 2000 to 2023 in study areas distributed across 47 countries, compiled through systematic queries of the Web of Science and Scopus catalogs. The results show an increase in the number of publications from 2012 onwards, with most studies performing landslide susceptibility analyses on cultural heritage sites. The majority of the studies deployed a geomorphological approach address slope instability mechanisms that threaten site integrity, with a significant number of publications presenting model-based, multidisciplinary and engineering geological approaches. Europe, North America, and Asia and the Pacific concentrate the majority of studies, with Italy and China having the highest number of case studies. The threats to cultural heritage sites located in Latin America and the Caribbean, and Africa are the least studied. Block slides, earth slides, and rock falls are the most studied processes, with fewer studies dealing with other landslide types. [ABSTRACT FROM AUTHOR]

The Canadian Cordillera in the province of British Columbia witnesses numerous rock falls every year. Studies on the recorded rock fall data in this area show that rock fall hazard follows weather conditions, especially precipitation and freeze-thaw cycles. This relationship indicates that a weather-based approach can be implemented to estimate possible changes in the rock fall hazard due to climate change. In this paper, we used a statistical approach to quantify the relationship between monthly weather averages and rock fall frequencies for a section of a transportation corridor along the Fraser River in British Columbia, Canada. In this regard, von Mises distributions are used to find the best-fitted models to the monthly precipitation and freeze-thaw cycles, and proper relative weights are applied to the models in order to calibrate them to the rock fall monthly frequency. The calibrated model is used with input data from climatic predictions for 2041–2070 and 2071–2100 to see how rock fall distribution will be affected due to climate change in the future decades. Results show that between 9 and 19%, more rock fall is anticipated in future winters. Rock falls are expected to decrease in other months, especially in October, November, March, and April. This paper presents a method to predict changes in rock fall hazard seasonality due to climate change and illustrates the method with a case study along a section of the Canadian Cordillera. [ABSTRACT FROM AUTHOR]

The overarching goal of the study was the development of a potentially dynamic rockfall susceptibility model by including climate predictors. The work is based on previously defined critical thresholds relating three climate indices — effective water inputs (EWI), wet-dry cycles (WD) and freeze–thaw cycles (FT) — and rockfall occurrence. The pilot area is located in the Aosta Valley region (Italian Western Alps). The susceptibility model settings were optimized through a stepwise procedure, carried out by means of generalized additive models (GAM). Predictors included topographic, climatic and additional snow-related variables. As climatic predictors, the mean annual threshold exceedance frequency was calculated for each index. All models were developed including an automatic penalization of statistically non-significant variables (i.e. shrinkage). The initial susceptibility model was set without considering potential inventory bias. Secondly, a "visibility mask" was produced to limit the modelling domain according to the rockfall event census procedures. Thirdly, GAMs functional relationships were analysed to verify the physical plausibility of predictors. Finally, to reduce concurvity, a principal component analysis (PCA) including climatic and snow-related predictors was carried out. Key findings were as follows: (i) ignoring inventory bias led to excellent model performance but to physically implausible outputs; (ii) the selection of non-rockfall points inside a "visibility mask" is effective in managing inventory bias influence on outputs; (iii) the inclusion of climate predictors resulted in an improvement of the physical interpretability of the associated models and susceptibility maps, being EWI, WD and the maximum cumulated snow melting the most important physically plausible climate predictors; (iv) the PCA strategy can efficiently reduce model concurvity. [ABSTRACT FROM AUTHOR]