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This Final Degree Project aims to explore in detail the possibilities offered by Mixed Reality through the use of the Microsoft HoloLens 2 immersive visualization glasses in the inspection of 3D models of the slopes under study. This research is part of the GeoRisk project, which is based on the use of real data collected over the past few years, both by the project itself and by the Cartographic and Geological Institute of Catalonia. Additionally, this project also includes data obtained from the EROSLOP project, which studies erosion in the Vallcebre area (Berguedà, Catalonia). The main objective of this work is to evaluate how Mixed Reality has been used in various fields so far, with the intention of extracting relevant details and applying them specifically to the study of slopes. Through the use of the ClirioView application for the Microsoft HoloLens 2 glasses, a detailed analysis of the functionalities and potential offered by this application is conducted. The ultimate goal of this exploration is to improve the ability to visualize and detect changes in these environments to achieve a better understanding of the natural phenomena affecting them.

Rockfalls are natural phenomena that consist of the separation of a certain mass of rock from the massif and its movement down the slope. The initial volume can be large, in which case we speak of rock avalanches, but in general, there is a disaggregation, at origin or by successive impacts, making it possible to study the phenomenon as the propagation of a certain number of rock-blocks. The behaviour of each of these blocks follows trajectories with sections of parabolic movement, followed by impacts with the slope (an event with eventual fragmentation), rebounds, rolling and sliding, until the stopping point. This master's thesis work focuses on the visualization of rockfalls, considering fragmentation, in a 3D environment, through Mixed Reality with the help of the holographic device HoloLens 2, with the aim of understanding the impact and global scope of this type of instability, and evaluate the associated damages. Immersive visualization in Mixed Reality must facilitate the transmission of results of the rockfall risk analysis to the stakeholders (designers, experts, authorities, community), as well as the development of a tool that helps the transmission of knowledge in the educational, professional and research fields. After investigating the appropriate methodology to introduce topography and trajectories in the Mixed Reality environment, a non-trivial task, it has been applied to two real cases, in order to create two prototypes that demonstrate the possibilities and limitations of this new technological paradigm. The first case is located in the Foj quarry (municipality of Vallirana); the second case corresponds to the simulation of the failure of the Oliver slab (Montserrat massif), both in the province of Barcelona, Spain. To design these Mixed Reality application prototypes, digital terrain models were used (built up using drone-photogrammetry or LiDAR), and trajectories previously generated with the RockGIS code for numerical simulation of rockfalls including fragmentation. The creation of these prototypes required the optimization of the data to be displayed, and the creation of tools to manipulate objects that move under the effects of gravity, the visualization of animations, and the manipulation of the model, managing to modify its size and position. All of this focused on the user's interaction with the 3D models to be viewed in Mixed Reality. During the development, different challenges arose, concentrating a great programming effort on the visualization of the trajectories of the blocks: data files had too many points (excessive for the resolution and processing capacity of the Hololens 2), in formats not directly compatible with the software used to develop Mixed Reality applications. This being the critical task of this work, it involved various tests, adjustments and iterations to achieve the working models presented here.

In this project, the workflow of a block that is perceived as risky was followed, the block is called “Oliver”. The block is located in the Montserrat massif, at kilometer 3+000 of the BP-1103 highway. The stability of the block, to overturning and sliding, was studied through limit equilibrium methods. It was instrumented and monitored for a period of almost a year. The study was completed with modeling of the rock fall trajectories taking into account the vegetation present on the slope. The stability study could not go beyond what is considered an approximation or schematic study because the equations used simplify the complexity of the block into geometric figures. Another limitation was the uncertainty about the union between the block and the rock mass, as well as the nature of the joint that between them. The monitoring gave promising results by defining a daily variation range of 0.003° and a change in the inclination measured on the B axis of 0.3° during the warm season of the year. The modeling of the trajectories was initially carried out without considering the vegetation, this gave a simulation of great propagation along the slope. Once the effect of this was introduced, the extension of the blocks was significantly reduced and the danger that these blocks represent to the road was completely eliminated. In the discussion of results and in the conclusions, the areas of uncertainty and the data that should be investigated in greater depth are pointed out to improve this type of analysis in the area of the Montserrat massif.

The mountain of Montserrat, located 50 km northwest of Barcelona, represents a long history of tradition and culture in Catalonia to which millions of people come year after year. Geologically, it is a rocky structure, formed mainly by conglomerates, siltstones and sandstones. In recent years, due to the landslides that occurred between 2006 and 2010 in the Degotalls sector, close to the monastery and with damage to infrastructures, the dangerousness of this particular massif was evidenced. It is for this purpose that the Cartographic and Geological Institute of Catalonia (ICGC) carries out the study and monitoring of rockfalls with the intention of mitigating the effects and reducing vulnerability in the areas of greatest exposure of Montserrat. In this context, the present work aims to detect rockfalls that occurred in 3 study areas of Montserrat with data obtained with a terrestrial laser scanner from July 2019 to December 2020, having 4 monitoring campaigns.

The Monasterio de Piedra Natural Park, located in Zaragoza - Spain, is classified as a National Monument and Asset of Cultural Interest, and annually receives thousands of visitors who walk its various paths and landscapes, where the Piedra River runs and crosses a huge cliff geologically shaped by limestone. The main goal of the present Thesis is the comparative study of the techniques/algorithms for the detection of detached blocks in rockfall source areas with Terrestrial Laser Scanning (TLS). This study was carried out with an applied approach, working with real data of several rockfall areas monitored during the past few years within research projects of the Department of Civil and Environmental Engineering from Universitat Politècnica de Catalunya (UPC). The data processing (point clouds) was carried out through the use of advanced commercial software, which allowed the identification of 15 rock block slides with volumes from 0.01 m3 to 26 m3, predominantly volumes up to 0.10 m3. The comparison of the results obtained in the present work and those obtained by other software, show that the procedure carried out to detect displacements and / or rockfalls, presents similar and acceptable values for all the analyzed sectors, taking into account that each one uses a different algorithm, C2M and M3C2 respectively. However, the differences are presented for blocks with volumes greater than 1 m3, but these differences are also observed in the cases that the errors of the root mean square or RMS of the final records are equal to or greater than 0.020 meters.

Nowadays laser scanning is one of the most popular techniques in modern surveying, it is very useful in different work cases. Laser scanning (also known as LIDAR) uses the laser beam to determine the distance to the points, which has the ability to generate pointclouds. This enables us to create different types of mesh, depending on where it is pointing. This project aims to support with laser scanning and total station data acquisition, to different tests under development at the Structural Laboratory (UPC). This includes amont other tasks: - to design the data collection with both devices; - raw data processing (cleaning outliers, noise filtering and so on); and, finally, - the transformation of the coordinates to a common reference system in order to get the displacements of the key points in the frame along time. There are several types of laser scanning modes, depending which is the objective (Balsavias, 1999). Aerial Laser Scanning (ALS) can determine different ground surfaces from a small plane, it covers more surface than terrestrial laser scanning. Aerial laser scanning data is used for topographic and cartographic surveys and for the creation of 3D terrain models, and also 3D city models (modelling of buildings and constructions). In other words, to analyse, built up territories. Terrestial Laser Scanning (TLS) determines surfaces of single objects or small surfaces from the ground, is closer to objects than aerial laser scanning so it have more resolution and accuracy. Structural load tests are done in a laboratory to check designs and validate calculation codes. Classically, linear unit deformations are measured in a timely manner, with strain gauges, displacement transducers (LVDTs for instance) and micrometers. During the tests that are carried out at DECA Laboratory of Structures and Materials Technology (Departament d'Enginyeria Civil i Ambiental, C1 building, Campus Nord, UPC, Barcelona, Spain) on 4 stainless steel frames, the measurement with Terrestrial Laser Scanner has been tested to track the global (3D) changes during the application of progressive loads. Measurements with Total Station to several targets on the frame have been carried out also to achieve more accuracy. For this purpose, several reflective targets were placed on the steel, which had good visibility for the Total Station and for the TLS. This project is also based in inserting both data collected in the same coordinate system, which gives the possibility to compare the two data collected and find results. It is interesting to know how digital information can vary from one device to the other, laser scan generates millions of points while total station generates hundreds but with more accuracy. All these tasks aim to the exploration of the new techniques which, eventually, may lead to an improvement in the structural test performance. It is worth to say that the measuring approach developed in this TFG in a non-contact or remote technique, in contrast with the classical sensors (strain gauges, LVDTs and so on). The main objective of this project is to assess the performance and contribution of the total station and the terrestrial laser scanning during testing of steel frames. With Terrestrial Laser Scanning, the objective is to collect data before, during and after the load tests, processing the resulting data with some-pointcloud softwares in order to generate the frame displacement field. The objective with the Total Station is to determine the initial state of the steel frames, highlighting their geometrical irregularities (if any). The frame final state is measured as well. The expected net results for each load tests are 8 to 10 3D models of each frame (TLS), corresponding to different times. On the other hand, by means of the Total Station we will get an accurate frame geometry at the beginning and at the end of each test (20-30 select points for each steel frame). As previously stated, all these results will help in identifying any possible geometrical irregularity in the shape and surface of the steel beam: initial defects produced during the frame manufacturing, and/or dents or sags resulting from the loading tests itself. As secondary objectives, this project wants to show the contribution of the non-contact, masive and remote geomatics techniques to complement traditional systems (Total Station) in this type of testing and environment (small scale testing of structures), working out the achievable resolutions and precisions. Additionally, the integration of total station and terrestrial laser scanning results in the same coordinate system is envisaged; the behaviour of the targets for this purpose will be assessed.

A un TFG anterior es va instal·lar una xarxa de control dels moviments a la Cadireta d'Agulles de Montserrat. Les mesures es duien a terme amb una Estació Total TM30 en operació manual. Es tractaria de automatitzar la tasca tot controlant la TM30 des d'un portàtil. El TFM abastarà també altres tècniques i altres blocs inestables a l'esmentada zona de Montserrat.

Els despreniments rocosos son fenòmens d'inestabilitat freqüents en vies de comunicació, mines a cel obert, vessants escarpats i penya-segats. Existeixen models que ajuden a simular les trajectòries dels blocs un cop despresos. La fragmentació del bloc original en fragments, quan succeeix, és crítica per a determinar la perillositat (nombre de fragments, punts de pas). A 2 projectes de recerca del Plan Nacional anomenats RockRisk i RockModels, s'estan duent a terme assaigs escala real per estudiar el fenómen de la fragmentació (% d'ocurrència, modus de fragmentació).

Aquest treball consisteix en l'anàlisi i interpretació de mesures de deformació amb interferometria Radar (GBSAR) dutes a terme durant un assaig a llarg termini a escala real. L'element monitoritzat és una llosa experimental que s'està monitoritzant al llarg d'un any per veure la seva retracció amb el pas del temps i la seva dilatació per causes climàtiques (canvi de temperatura).

This TFG describes the stability problems which can occur in open cast excavations. It focuses on the typical failure modes of a dolomitic quarry (North of Hungary) as characterized through field investigations. The candidate has to carry out his/her own rock slope stability assessment. The main aim of the thesis is the optimization of the slope angle within the constraints given by the mining engineers and the practice. The input parameters for the calculations should be derived from in situ and laboratory tests.

Este trabajo de fin de grado se engloba dentro del encargo que hace la Autoritat Portuària de Barcelona (APB) a la Universitat Politècnica de Catalunya (UPC) para enlazar altimétricamente los distintos mareógrafos que hay en el Puerto. El objetivo principal del TFG es la medición del movimiento del puente Puerta de Europa y dar cota ortométrica a unos puntos distribuidos sobre las bases de las pilonas del puente, para así poder enlazar el mareógrafo de Puertos del Estado, que está situado junto a la torre de prácticos, y el mareógrafo de la APB, situado bajo la base este de las pilonas del puente. Además, también se enlazará el mareógrafo de la UPC que está situado junto al de la APB. Para ello, se realiza una nivelación geométrica de alta precisión.

En la montaña de Montserrat se encuentra la Cadireta d'Agulles, un bloque de conglomerado que presenta un fuerte extraplomado que hace temer por su nivel de estabilidad presente y futura. Se debe considerar también la progresiva erosión de los materiales arcillosos situados en el contacto con la base y la profundización de la diaclasa que la separa de la aguja vecina. Sin duda, como otras muchas agujas de Montserrat, La Cadireta acabará cayendo en unos pocos cientos o miles de años. El presente TFG aborda el primer estudio geomecánico de la estabilidad de la Cadireta.Para poder calcular los volúmenes y centros de gravedad, se ha realizado un modelado 3D mediante la captura masiva de fotografías alrededor de la Aguja y su solapado fotogramétrico. Como en muchas situaciones donde los modelos numéricos tienen limitaciones para describir al 100% la compleja realidad, se ha pensado en la conveniencia de implantar un dispositivo de monitorización y control de desplazamientos para la Cadireta, que permita el seguimiento de posibles movimientos a medio y largo plazo. Este dispositivo se ha diseñado, instalado y medido dentro del presente TFG. La conclusión principal del trabajo es que la Cadireta se encuentra en una situación de seguridad suficiente. Ello se debe fundamentalmente a la contribución estabilizadora de esfuerzos horizontales de tracción transmitidos por la diaclasa que conecta la base de la Cadireta con la aguja posterior; por otro lado la sección horizontal que está en la base del bloque tiene en la actualidad suficiente superficie activa. No obstante la configuración de esfuerzos en el conjunto de la aguja indica definitivamente una posible degradación de la estabilidad con el paso del tiempo, lo cual daría paso al colapso de la Cadireta. Esta catástrofe no es en absoluto inminente, pueden pasar siglos; podría incluso ser evitada si se adoptaran medidas de estabilización, algunas de las cuales se apuntan en el propio TFG.