Application of three‐dimensional rockfall modelling to rock face engineering

Cliffs formed in columnar jointed basalt have the proper geometry and discontinuities to initiate rockfall events. There are a number of locations in Boise, Idaho that may experience rockfall events from columnar jointed basalt cliffs. Publicly available LiDAR data coupled with site reconnaissance activities were used to develop calibrated two-dimensional rockfall models at a study site in southeast Boise. Photogrammetry was used to determine the volume of seven calibration boulders. The study site, located on Whitney Terrace, consists of a columnar jointed basalt cliff followed by a slope with a subdivision at the toe of the slope. The two common approaches used to generate rockfall models are the Lumped Mass and Rigid Body methods. At this site, the Rigid Body method that incorporated vegetative properties was demonstrated to be the most appropriate method for the rockfall model. Rockfall model calibration was performed by comparing the model-simulated runout distances and geolocations of the seven calibration boulders. The rockfall models were considered calibrated when the location of the calibrated boulder was within one-half of the standard deviation of the mean runout distance of the furthest traveling grouping of simulated rocks. The calibration provided a range of restitution coefficients that were used to develop predictive runout maps for rocks of various masses for the site. The rock sizes used for the predictive runout maps are based on the range of sizes of runout boulders at the site. The predictive runout maps showed site vegetation acts as a barrier or energy dissipater for 50 kg and 100 kg simulated rocks. This mass of rocks had shorter runout distances compared to the 400 kg, 800 kg, and 1500 kg simulated rocks. There was only one location within the study area where large, 800 kg and 1500 kg, simulated rocks would runout past the study area and into the subdivision. Three recommendations are provided for future work. Firstly, since size and shape are important inputs to Rigid Body rockfall models, more effort should be used to accurately determine these properties. Second, publicly available LiDAR data had to be augmented with field data. Future studies should incorporate site-specific LiDAR data collected with either a terrestrial LiDAR scanner or UAV LiDAR. Finally, three-dimensional rockfall models should be used because they incorporate full-site topography and allow simulated rocks to spread downslope and laterally.

We used the coupled forest and rockfall model PICUS Rock’n’Roll, linking a hybrid forest patch model and a 3D rockfall model, to assess the effects of four management scenarios (BAU: business as usual age class shelterwood approach; PFM1 and PFM2: rockfall protection management scenarios with slit-shaped gaps; NOM: no management scenario without any active silvicultural intervention) on rockfall protection and timber production on a 38 ha slope over 100 years. Compared to PFM1 and PFM2, we found slightly more harvested timber for the BAU scenario (BAU: 6.7 m³ha−1yr−1, PFM: 5.7–5.9 m³ha−1yr−1), but lower contribution margins (BAU: 55 €ha−1yr−1, PFM: 113–115 €ha−1yr−1). Overall, depending on rock size and forest state, 30–70% of the simulated rocks that would otherwise hit the road at the foot of the slope were stopped by the forest. While the PFM scenarios maintained a high rockfall protection level over 100 years (PE between 45–64%) the BAU showed periods of reduced protection (PE between 26–65%). The NOM scenario maintained favorable conditions in the beginning, but declining protection efficiency in the last decades of the century (PE 49–63%). We conclude that rockfall protection management can outperform BAU with regard to both timber production and rockfall protection.

Rockfall modelling in Caminito del Rey (Málaga, Spain) represents a scientific and technical challenge due to the high geomorphological complexity of the environment, characterized by vertical cliffs, numerous overhangs, and complex geometries. In this context, within one of Malaga’s most visited tourist attractions (more than 300,000 people per year), a comprehensive study was required to address challenges across all phases, from the detailed characterization of the inventory to trajectory modelling. To address these difficulties, the most advanced technology currently available for remote data adquisitation (UAV, LIDAR and satellite) and three-dimensional modelling was used, along with the development and application of ad hoc methods and techniques specifically tailored to this study.The high-precision georeferenced digital rockfall inventory had to tackle issues such as data heterogeneity, limitations in the available documentation, and errors related to mapping accuracy of the trail layout. On the other hand, the modelling process required a multiscale approach, examining all sections of Caminito del Rey with a focus on detailed scales for individual blocks. Custom input data were obtained for this purpose: (i) elevation models accounting for overhangs and both gorge walls; (ii) source areas for rockfalls derived using probabilistic approaches; (iii) block size estimation based on lithology type; and (iv) calibration and validation of the three coefficients maps in narrow and vertical sections (i.e., dynamic rolling friction, normal energy restitution, and tangential energy restitution) that simulate energy loss by a boulder when rolling and bouncing at impact points.Reducing uncertainty in each input dataset is essential not only for improving the reliability and accuracy of analytical models but also for effectively establishing preventive measures. Furthermore, it plays a key role in identifying critical areas that require continuous monitoring. This abstract was supported by the KINGSTONE project, the Rockfall Susceptibility Study in Caminito del Rey (a collaboration among IGME-CSIC, the University of Granada, the University of Jaén, and the Caminito del Rey UTE), and the SARAI project (PID2020-116540RB-C21), funded by MCIN/AEI/10.13039/501100011033.

Rockfall hazard is a main threat for mountainous and hilly areas that can cause loss of life, damage to infrastructures, and traffic interruption. Rockfall frequency and magnitude vary both spatially and temporally; therefore, multi-scenarios related to rockfall characteristics (trajectories, frequency and kinetic energy) can provide early warnings by identifying the areas at risk for mitigation purposes. The aim of this study is to predict the areas at risk from future rockfall incidents and suggest suitable mitigation measures to prevent them. The most significant elements in rockfall analysis are slope topography interpretation or the digital elevation model (DEM) and the rockfall modeling approach. Light detection and ranging (LiDAR) techniques have been widely used in rockfall studies because of their capability to provide high-resolution information regarding slope surfaces. In the current study, airborne laser scanning (ALS) is used to obtain a high-density point cloud (4 pts./m2) of the study area for the construction of an accurate DEM via a geographic information system. Rockfall source areas were identified based on multi-criteria method including DEM derivatives (e.g., slope, aspect, curvature and topographic contrast) in addition to terrain type and aerial photos. A 3D rockfall model has been established to determine rockfall multi-scenarios based on their characteristics according to a range of restitution coefficient (normal and tangential) and friction angle values; these parameters are particularly crucial in rockfall simulation to delineate the spatial prediction of rockfall hazard areas along the Jelapang corridor of the North–South Expressway in Malaysia. In addition, a barrier location was suggested based on limited rockfall height and kinetic energy to mitigate rockfall hazards. Results show that rockfall trajectories (stopping distance) and, subsequently, their frequency and energy are increased; moreover, barrier efficiency is reduced when the values of the mechanical parameters (Rn, Rt, and friction angle) are increased. Nonetheless, the suggested barrier location is an efficient and mitigative measure to eliminate the rockfall effect.

Rockfalls are a major threat to settlements and transportation routes in many places. Although the general protective effect of forests against rockfalls is currently not questioned, little is known about the ideal properties of a forest stand that provides good protection. Therefore, in this study the question was assessed of how mountainous forests may influence rockfalls of single boulders. An actual rockfall trajectory was measured, recorded, analysed and simulated with a rockfall model. Rockfalls into different forest scenarios were also modelled for the site. Results showed that the actual rockfall event can be well simulated. Furthermore, a completely forested slope reduces velocity and energy of the falling blocks much better than a sparsely forested slope. For the profile discussed in this paper, the largest effect upon falling 3 m3 blocks was obtained with a high forest containing 350 trees per ha. The results confirmed common assumptions on ideal properties of a protective forest stand against rockfalls.

The basic idea behind the use of 3-dimensional (3D) tools in biomedical research is the assumption that the structures under study will perform at the best in vitro if cultivated in an environment that is as similar as possible to their natural in vivo embedding. Tissue slicing fulfills this premise optimally: it is an accessible, unexpensive, imaging-friendly, and technically rather simple procedure which largely preserves the extracellular matrix and includes all or at least most supportive cell types in the correct tissue architecture with little cellular damage. Vibrating microtomes (vibratomes) can further improve the quality of the generated slices because of the lateral, saw-like movement of the blade, which significantly reduces tissue pulling or tearing compared to a straight cut. In spite of its obvious advantages, vibrating microtome slices are rather underrepresented in the current discussion on 3D tools, which is dominated by methods as organoids, organ-on-chip and bioprinting. Here, we review the development of vibrating microtome tissue slices, the major technical features underlying its application, as well as its current use and potential advances, such as a combination with novel microfluidic culture chambers. Once fully integrated into the 3D toolbox, tissue slices may significantly contribute to decrease the use of laboratory animals and is likely to have a strong impact on basic and translational research as well as drug screening.

Conventional barrier systems have performed well for occupants of passenger cars and trucks, but their effects on other road user groups, especially motorcyclists, usually result in greater injuries. This study is purposed to improve the safety features of an existing guardrail system with regard to motorcyclists. It is aimed to reduce the severity of injuries sustained by the motorcyclists during the event of impact and containing the motorcycles and the riders. There is a relative lack of published materials regarding the nature of motorcycle collisions with roadside barriers. Various features of existing guardrail systems particularly the barrier posts were identified in the literature, presenting significant risks to fallen motorcyclists. Numerous strategies have been employed to better protect the motorcyclists from impacts with guardrails. The present study has employed polypropylene as material coupled with V-profile rails to give the new guardrail design. Weighing procedures were also conducted to determine the centre of gravity of the motorcycle. Three-dimensional computer models which consist of a newly designed V-beam guardrail and equivalent kinetic characteristics of a motorcycle were developed. The event of collision between the motorcycle and the guardrail was then simulated using computer finite element program, Algor. The simulations were conducted for three impact configurations, with the impact angle between the motorcycle and the guardrail at 90°, 45° and 20° at an impact velocity of 60 km/h. The results show the newly designed V-beam guardrail has more forgiving and better energy-absorbed characteristics than the existing design the conventional W-beam design.

Rockfall hazard zoning is not simple to achieve in practice. It involves the different factors: rock block shape and size, characteristics of the topography, and the occurrence of rockfall which depends on some triggering events that cause a change in the forces acting a rock block. Rockfall hazard maps are often replaced with figures which show the frequency and the corresponding intensity of a predefined rock magnitude. Some attempts are introducing the results of the three-dimensional numerical modeling to get the objective zoning based on the mechanical parameters (e.g. kinetic energy). In such attempts, it is important to recognize that the mechanical parameters may be affected by modeling of the physical factors mentioned above. The most important role of the three-dimensional simulation is to display the lateral dispersion of trajectories. In this paper, the influence of controlling factors on the dispersion has been evaluated by conducting 3D simulation. Parametric simulations have been performed at different spatial resolutions using sets of synthetic biplanar slopes characterized by mean inclination and local asperities. The results of the lateral dispersion of trajectories are explained with the width of computed trajectories and the fixed distance along the slope surface from the block launch position.

Geological sequestration has been proposed as a viable option for mitigating the vast amount of CO{sub 2} being released into the atmosphere daily. Test sites for CO{sub 2} injection have been appearing across the world to ascertain the feasibility of capturing and sequestering carbon dioxide. A major concern with full scale implementation is monitoring and verifying the permanence of injected CO{sub 2}. Geophysical methods, an exploration industry standard, are non-invasive imaging techniques that can be implemented to address that concern. Geophysical methods, seismic and electromagnetic, play a crucial role in monitoring the subsurface pre- and post-injection. Seismic techniques have been the most popular but electromagnetic methods are gaining interest. The primary goal of this project was to develop a new geophysical tool, a software program called GphyzCO2, to investigate the implementation of geophysical monitoring for detecting injected CO{sub 2} at test sites. The GphyzCO2 software consists of interconnected programs that encompass well logging, seismic, and electromagnetic methods. The software enables users to design and execute 3D surface-to-surface (conventional surface seismic) and borehole-to-borehole (cross-hole seismic and electromagnetic methods) numerical modeling surveys. The generalized flow of the program begins with building a complex 3D subsurface geological model, assigning properties to the models that mimic a potential CO{sub 2} injection site, numerically forward model a geophysical survey, and analyze the results. A test site located in Warren County, Ohio was selected as the test site for the full implementation of GphyzCO2. Specific interest was placed on a potential reservoir target, the Mount Simon Sandstone, and cap rock, the Eau Claire Formation. Analysis of the test site included well log data, physical property measurements (porosity), core sample resistivity measurements, calculating electrical permittivity values, seismic data collection, and seismic interpretation. The data was input into GphyzCO2 to demonstrate a full implementation of the software capabilities. Part of the implementation investigated the limits of using geophysical methods to monitor CO{sub 2} injection sites. The results show that cross-hole EM numerical surveys are limited to under 100 meter borehole separation. Those results were utilized in executing numerical EM surveys that contain hypothetical CO{sub 2} injections. The outcome of the forward modeling shows that EM methods can detect the presence of CO{sub 2}.

Rockfall simulations are often performed at various levels of detail depending on the required safety margins of rockfall-hazard-related assessments. As a pseudo benchmark, the simulation results from different models can be put side-by-side and compared with reconstructed rockfall trajectories, and mapped deposited block fragments from real events. This allows for assessing the objectivity, predictability, and sensitivity of the models. For this exercise, mapped data of past events from the Mel de la Niva site are used in this paper for a qualitative comparison with simulation results obtained from early calibration stages of the Flow-R 2.0.9, Rockyfor3D 5.2.15 and RAMMS::ROCKFALL 1.6.70 software. The large block fragments, reaching hundreds of megajoules during their fall, greatly exceed the rockfall energies of the empirical databases used for the development of most rockfall models. The comparison for this challenging site shows that the models could be improved and that combining the use of software programs with different behaviors could be a workaround in the interim. The findings also highlight the inconvenient importance of calibrating the simulations on a per-site basis from onsite observations. To complement this process, a back calculation tool is briefly described and provided. This work also emphasizes the need to better understand rockfall dynamics to help improve rebound models.

RockFall analyst: A GIS extension for three-dimensional and spatially distributed rockfall hazard modeling

Gostomel, Kyiv region using 3D tools Purpose. This study aims to develop and evaluate the effectiveness of an innovative approach to urban landscape restoration and reorganization using modern 3D design technologies. The use of 3D tools seeks to enhance planning accuracy, improve visualization of design solutions, optimize stakeholder engagement, and minimize potential errors during implementation. Methodology. To achieve the research objective, a comprehensive approach was applied, including analysis of the existing situation, assessment of local residents' needs, development of conceptual ideas using 3D modeling and visualization, a systematic review of literature considering ecological factors, and the creation of an integrated landscape design concept. Resultsin findings in the field of landscape design for renewable territories indicate a lack of comprehensiveness, limited consideration of long-term impacts, absence of interdisciplinary integration, and project adaptability, particularly in the context of post-traumatic recovery. Scientific novelty of the study lies in the development of a comprehensive approach to urban area restoration that integrates advanced 3D modeling technologies, taking into account social, environmental, and economic factors. This innovative approach facilitates the creation of adaptive landscape design models aligned with community needs and environmental conditions. Practical Significance. Implementing innovative approaches to landscape design underscores the importance of developing research methodologies that consider aspects of creating effective and sustainable projects in the field of urban territory restoration. Analyzing modern tools contributes to industry development, enhancing competitiveness and enabling the adoption of new technical and design solutions.

Sketching 3D immersed experiences often require the designer to use some 3D modelling tool. The tools slow down the designers and can be a hindrance to the creative process. Moreover, the results often have the appearance of finished products. Hand sketching however, allows the designer more rapidly to express ideas that suddenly emerge and quickly disappear. Moreover, sketches drawn by hand have the advantage of looking unfinished. This paper proposes a simple method for making 3D sketches by hand and even on paper. Tool support is provided for transforming the sketches into 3D models that can be viewed using standard viewers that give viewers the immersed experience. The sketches can also be overlaid on existing panoramic images used for backgrounds. Sketches of 3D scenes and models are created by sketching various cross-sections of the scene from various angles. Several cases are used to illustrate how the framework is used. The sketches are viewed using a standard off-the-shelf panorama or point cloud viewers.

The coming years will see routine use of solar data of unprecedented spatial and spectral resolution, time cadence, and completeness in the wavelength domain. To capitalize on the soon to be available radio facilities such as the expanded OVSA, SSRT and FASR, and the challenges they present in the visualization and synthesis of the multi-frequency datasets, we propose that realistic, sophisticated 3D active region and flare modeling is timely now and will be a forefront of coronal studies over the coming years. Here we summarize our 3D modeling efforts, aimed at forward fitting of imaging spectroscopy data, and describe currently available 3D modeling tools. We also discuss plans for future generalization of our modeling tools.

19 - Three-Dimensional Bone Angle Quantification